TW202442723A - Resin composition, cured product, resin film, prepreg, laminate, and printed wiring board - Google Patents

Abstract

The present invention provides a resin composition that can produce a cured product having a low dielectric constant, a low dielectric dissipation factor and excellent heat resistance. The resin composition of the present invention contains: a copolymer (A) and a copolymer (B) having a vinyl aromatic monomer unit and a covalent diene monomer unit, and one or more of (I) to (III); and the resin composition satisfies the following conditions. (I): Cured resin (excluding copolymers (A) and (B)) (II): Free radical initiator (III): Curing agent (excluding component (I)) The Mn of copolymer (A) is 40,000 or less. Copolymers (A) and (B) have one or more polymer blocks mainly composed of vinyl aromatic monomer units. The Mn of copolymer (B) is 80,000 or more. The difference ΔBS between the content (BS) of the polymer block mainly composed of vinyl aromatic monomer units of copolymers (A) and (B) is 20% by mass or less. The average value of the content of the vinyl aromatic monomer units of copolymers (A) and (B) is 40% by mass or less. The (BSb) of copolymer (B) is 10% by mass or more.

Description

Resin composition, cured product, resin film, prepreg, laminate, and printed wiring board

The present invention relates to a resin composition, a cured product, a resin film, a prepreg, a laminate, and a printed wiring board.

In recent years, with the significant progress of information network technology and the expansion of services that effectively utilize information networks, electronic equipment is required to have larger information capacity and faster processing speed. In order to meet these requirements, various substrate materials such as printed circuit boards and flexible substrates are required to have materials with lower dielectric loss.

In order to obtain materials with less dielectric loss, research and disclosure have been conducted on thermosetting resins such as epoxy resins with low dielectric constants and low dielectric dissipation factors and excellent mechanical properties such as strength and heat resistance, or cured resins with thermoplastic resins such as polyphenylene ether resins as the main component. However, from the perspective of low dielectric constants and low dielectric dissipation factors, the previously disclosed materials still have room for improvement. When they are used in printed circuit boards, there is a problem of limited information volume and processing speed.

In order to improve this problem, various rubber components have been proposed as modifiers for the thermosetting resin or thermoplastic resin as described above. For example, Patent Document 1 discloses at least one elastomer selected from the group consisting of a block copolymer of a vinyl aromatic compound and an olefinic hydrocarbon compound and its hydride, and a homopolymer of a vinyl aromatic compound as a modifier for lowering the dielectric loss factor and the dielectric constant of a polyphenylene ether resin. In addition, Patent Document 2 discloses a styrene-based elastomer as a modifier for lowering the dielectric loss factor and the dielectric constant of an epoxy resin. [Prior Art Document] [Patent Document]

[Patent document 1] Japanese Patent Publication No. 2021-147486 [Patent document 2] Japanese Patent Publication No. 2020-15861

However, the resin composition using the modifier disclosed in Patent Documents 1 and 2 has the following problems: the dielectric constant and dielectric dissipation factor are still not sufficiently low, and the heat resistance is reduced due to the addition of the modifier. In addition, the styrene elastomer previously used as the modifier has a problem of being limited in the amount of addition due to its insufficient solubility in varnish.

Therefore, the object of the present invention is to provide a resin composition capable of obtaining a cured product having a low dielectric constant and a low dielectric dissipation factor and excellent heat resistance, a cured product using the above resin composition, a resin film, a prepreg, a laminate, and a printed wiring board. [Technical means for solving the problem]

In order to solve the above-mentioned problems of the prior art, repeated and intensive research has been conducted, and it has been found that the above-mentioned problems can be solved by a resin composition containing the following substances, thereby completing the present invention: copolymers (A) and (B) which are copolymers of vinyl aromatic compounds and covalent diene compounds and have a specified structure; and at least one of a hardening resin, a free radical initiator, and a hardener. That is, the present invention is as follows.

[1] A resin composition comprising: a copolymer (A) having a vinyl aromatic monomer unit and a covalent diene monomer unit, a copolymer (B) having a vinyl aromatic monomer unit and a covalent diene monomer unit, and at least one component selected from the group consisting of the following components (I) to (III), and the resin composition satisfies the following <condition (1)> to <condition (7)>. Component (I): hardening resin (excluding copolymer (A) and copolymer (B)) Component (II): free radical initiator Component (III): hardening agent (excluding component (I)) <condition (1)>: The number average molecular weight of the above copolymer (A) is 40,000 or less. <Condition (2)>: The copolymer (A) has at least one polymer block mainly composed of vinyl aromatic monomer units. <Condition (3)>: The copolymer (B) has at least one polymer block mainly composed of vinyl aromatic monomer units. <Condition (4)>: The number average molecular weight of the copolymer (B) is 80,000 or more. <Condition (5)>: The difference (ΔBS) between the content (BSa) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (A) and the content (BSb) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (B) satisfies the following relationship. ΔBS＝｜BSa―BSb｜≦20 ＜Condition (6)＞： The average content of the vinyl aromatic monomer unit in the copolymer (A) and the copolymer (B) is 40% by mass or less. ＜Condition (7)＞： The content (BSb) of the polymer block mainly composed of the vinyl aromatic monomer unit in the copolymer (B) is 10% by mass or more. [2] The resin composition as described in [1] above, wherein the average hydrogenation rate (H) (%) of the unsaturated double bonds derived from the conjugated diene compound contained in the copolymer (A) and the copolymer (B) and the average vinyl bond content (V) (%) satisfy the following relationship. V＋10≦H [3] The resin composition described in [1] or [2] above, wherein the copolymer (B) is a block copolymer having a general structure: a1-b1-a2-c1, a1-b1-a2-b2, a1-c1-a2-c2, a1-c1-a2-b1, the a1 block and the a2 block are polymer blocks mainly composed of vinyl aromatic monomer units, the b1 block and the b2 block are random polymer blocks containing vinyl aromatic monomer units and covalent diene monomer units, the c1 block and the c2 block are polymer blocks mainly composed of covalent diene monomer units. [4] A resin composition as described in any one of [1] to [3] above, wherein the ratio (Mnb/Mna) of the number average molecular weight (Mnb) of the copolymer (B) to the number average molecular weight (Mna) of the copolymer (A) is greater than 4. [5] A resin composition as described in any one of [1] to [4] above, wherein the copolymer (A) is a block copolymer represented by the general structural formula: d-f, d is a polymer block mainly composed of vinyl aromatic monomer units, f is a polymer block mainly composed of covalent diene monomer units. [6] A cured product, which is a cured product of the resin composition as described in any one of [1] to [5] above. [7] A printed wiring board, which comprises the cured product as described in [6] above. [8] A resin film comprising a cured product as described in [6]. [9] A prepreg comprising a composite of a substrate and a resin composition as described in any one of [1] to [5]. [10] A prepreg comprising a composite of a substrate and a cured product as described in [6]. [11] The prepreg as described in [9], wherein the substrate is glass cloth. [12] The prepreg as described in [10], wherein the substrate is glass cloth. [13] A laminate comprising: A cured product of the resin film as described in [8], and A metal foil. [14] A laminate comprising: A cured product of the prepreg as described in [9], and A metal foil. [15] A laminate comprising: a cured product of the prepreg described in [10], and a metal foil. [16] A printed wiring board comprising the resin film described in [8]. [17] A printed wiring board comprising the prepreg described in [11]. [18] A printed wiring board comprising the prepreg described in [12]. [Effect of the invention]

According to the present invention, a resin composition capable of obtaining a cured product having a low dielectric constant, a low dielectric dissipation factor and excellent heat resistance, a cured product using the resin composition, a resin film, a prepreg, a laminate, and a printed wiring board can be obtained.

The following is a detailed description of the form used to implement the present invention (hereinafter referred to as "this embodiment"). Furthermore, the following embodiment is an example used to illustrate the present invention and is not intended to limit the present invention to the following contents. The present invention can be implemented in various ways within the scope of its main purpose.

[Resin composition] The resin composition of the present embodiment contains: A copolymer (A) having a vinyl aromatic monomer unit and a covalent diene monomer unit, A copolymer (B) having a vinyl aromatic monomer unit and a covalent diene monomer unit, and At least one component selected from the group consisting of the following components (I) to (III), and The resin composition satisfies the following <Condition (1)> to <Condition (7)>. Component (I): Curing resin (excluding copolymers (A) and (B)) Component (II): Free radical initiator Component (III): Curing agent (excluding component (I)) <Condition (1)>: The number average molecular weight of the above copolymer (A) is 40,000 or less. <Condition (2)>: The copolymer (A) has at least one polymer block mainly composed of vinyl aromatic monomer units. <Condition (3)>: The copolymer (B) has at least one polymer block mainly composed of vinyl aromatic monomer units. <Condition (4)>: The number average molecular weight of the copolymer (B) is 80,000 or more. <Condition (5)>: The difference (ΔBS) between the content (BSa) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (A) and the content (BSb) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (B) satisfies the following relationship. ΔBS＝｜BSa―BSb｜≦20 ＜Condition (6)＞： The average value of the content of the vinyl aromatic monomer unit of the above copolymer (A) and the copolymer (B) is 40% by mass or less. ＜Condition (7)＞： The content (BSb) of the polymer block mainly composed of the vinyl aromatic monomer unit of the above copolymer (B) is 10% by mass or more.

The resin composition of this embodiment can obtain a cured product having low dielectric constant and low dielectric dissipation factor and excellent heat resistance by having the above-mentioned structure. In addition, in this specification, when a polymerizable monomer is incorporated into a constituent element of a polymer, it is recorded as a "monomer unit", and when it is in the state of a monomer before becoming a constituent element of a polymer, it is recorded as a "compound".

(Copolymer (A)) The resin composition of this embodiment contains copolymer (A). Copolymer (A) is a copolymer having vinyl aromatic monomer units and covalent diene monomer units. The hydrogenated copolymer (A) has a number average molecular weight (Mna) of 40,000 or less and has at least one polymer block mainly composed of vinyl aromatic monomer units.

<Vinyl aromatic compound> Examples of the vinyl aromatic compound as the vinyl aromatic monomer unit forming the copolymer (A) include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-aminoethylstyrene and the like. Among them, styrene, α-methylstyrene and p-methylstyrene are preferred from the viewpoint of availability and productivity. These may be used alone or in combination of two or more.

<Conjugated diene compound> The conjugated diene compound as the conjugated diene monomer unit forming the copolymer (A) may be a diene having a conjugated double bond, and examples thereof include, but are not limited to, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, and farnesene. Among these, 1,3-butadiene and isoprene are preferred from the viewpoint of availability and productivity. These may be used alone or in combination of two or more.

<Condition (1)> The number average molecular weight (Mna) of the copolymer (A) is 40,000 or less, preferably 5,000 or more and less than 40,000, and more preferably 5,000 or more and less than 35,000. By making the number average molecular weight (Mna) of the copolymer (A) 40,000 or less, there is a tendency that the solubility of the copolymer (A) in the varnish becomes good. The number average molecular weight (Mna) of the copolymer (A) can be measured by gel permeation chromatography (hereinafter referred to as GPC) using standard polystyrene as a calibration curve. Specifically, it can be measured by the method described in the following examples. The number average molecular weight (Mna) of the copolymer (A) can be controlled within the above numerical range by adjusting the monomer addition amount, polymerization initiator addition amount and other conditions in the polymerization step.

In this specification, the so-called "vinyl bonding amount" means the ratio of 1,2-bonding and 3,4-bonding to the bonding mode of 1,2-bonding, 3,4-bonding and 1,4-bonding of the conjugated diene before hydrogenation. The vinyl bonding amount can be measured by nuclear magnetic resonance spectroscopy (NMR). The vinyl bonding amount can be arbitrarily controlled by using the following polar compounds, etc.

<Condition (2)> The copolymer (A) has at least one polymer block mainly composed of a vinyl aromatic monomer unit. By having at least one polymer block mainly composed of a vinyl aromatic monomer unit, the solubility of the copolymer (A) in the varnish tends to be improved.

Furthermore, in this specification, "as the main component" means that the monomer unit of the target is contained in the polymer block of the target at 95 mass % or more and 100 mass % or less. The copolymer (A) preferably has a polymer block containing vinyl aromatic monomer units as the main component (BAa) of 5 to 37 mass %, more preferably 7 to 35 mass %, and further preferably 10 to 32 mass %. By making the polymer block containing vinyl aromatic monomer units as the main component (BSa) of the copolymer (A) 5 mass % or more, there is a tendency that the solubility of the copolymer (A) relative to the varnish is improved. The content of the polymer block containing vinyl aromatic monomer units as the main component can be measured by NMR. Specifically, it can be measured by the method described in the following examples. The content (BSa) of the polymer block with vinyl aromatic monomer units as the main component of the copolymer (A) can be controlled within the above numerical range by adjusting the amount of monomer added in the polymerization step, the timing of addition, the polymerization time, etc.

The structure of the copolymer (A) is not limited, and for example, it is preferably a structure represented by the following general formula. de df (de) _n (df) _n ded dfd ef def dfe (de) _m -Z (df) _m -Z (def) _m -Z (dfe) _m -Z In the above formula, d, e, and f represent polymer blocks (d), (e), and (f), respectively. Among them, from the viewpoint of productivity, (de) _n and (df) _n are preferred, and de and df are further preferred. Furthermore, from the viewpoint of the turtle crack resistance of the resin composition of the present embodiment, it is more preferred that the copolymer (A) is df. When the copolymer (A) is df, there is a tendency that the toughness of the resin composition of the present embodiment is improved, and there is a tendency that the turtle crack resistance becomes good. Furthermore, the copolymer (A) may be a mixture containing a plurality of structures represented by the above general formula in an arbitrary ratio.

In the above general formulas representing copolymer (A), d is a polymer block mainly composed of vinyl aromatic monomer units, e is a polymer block mainly composed of covalent diene monomer units, and f is a random copolymer block containing vinyl aromatic monomer units and covalent diene monomer units. n is an integer greater than 1, preferably an integer from 1 to 10, and more preferably an integer from 1 to 5. m is an integer greater than 2, preferably an integer from 2 to 11, and more preferably an integer from 2 to 8. Z represents a coupling agent residue. Here, the coupling agent residue means the residue after bonding of the coupling agent used for bonding between polymer blocks (e) and between polymer blocks (f). As coupling agents, for example, the following polyhalogen compounds or acid esters can be cited, but they are not limited to them.

The vinyl aromatic monomer units in the polymer block (f) may be uniformly distributed or may be tapered. Furthermore, the vinyl aromatic monomer units may exist in a plurality of uniformly distributed portions and/or tapered portions. Furthermore, in the above polymer block (f), a plurality of portions with different contents of vinyl aromatic monomer units may coexist.

(Copolymer (B)) Copolymer (B) is a copolymer having a vinyl aromatic monomer unit and a covalent diene monomer unit. Copolymer (B) has at least one polymer block mainly composed of a vinyl aromatic monomer unit, a number average molecular weight (Mnb) of 80,000 or more, and a polymer block content (BSb) mainly composed of a vinyl aromatic monomer unit of 10% by mass or more.

<Vinyl aromatic compound> Examples of the vinyl aromatic compound forming the vinyl aromatic monomer unit constituting the copolymer (B) include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, divinylbenzene, 1,1-diphenylethylene, N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-aminoethylstyrene and the like. Among them, styrene, α-methylstyrene and p-methylstyrene are preferred from the viewpoint of availability and productivity. These may be used alone or in combination of two or more.

<Conjugated diene compound> The conjugated diene compound forming the conjugated diene monomer unit constituting the copolymer (B) may be any diene having a conjugated double bond, and examples thereof include, but are not limited to, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, and farnesene. Among these, 1,3-butadiene and isoprene are preferred from the viewpoint of availability and productivity. These may be used alone or in combination of two or more.

The copolymer (B) has at least one polymer block mainly composed of vinyl aromatic monomer units. When the copolymer (B) has a polymer block mainly composed of vinyl aromatic monomer units, the solubility of the copolymer (B) relative to the varnish tends to be improved.

In the copolymer (B), the content (BSb) of the polymer block mainly composed of vinyl aromatic monomer units is 10% by mass or more, preferably 13% by mass or more, more preferably 15% by mass or more, and further preferably 20% by mass or more. By making the content (BSb) of the polymer block mainly composed of vinyl aromatic monomer units of the copolymer (B) 10% by mass or more, the solubility of the copolymer (B) relative to the varnish is improved, and the degree of freedom in setting the amount of the copolymer (B) in the resin composition of the present embodiment is improved. The content of the polymer block mainly composed of vinyl aromatic monomer units can be measured by NMR. Specifically, it can be measured by the method described in the following embodiment. The content (BSb) of the polymer block with vinyl aromatic monomer units as the main component of the copolymer (B) can be controlled within the above numerical range by adjusting the amount of monomer added in the polymerization step, the timing of addition, the polymerization time, etc.

The number average molecular weight (Mnb) of the copolymer (B) is 80,000 or more, preferably 100,000 or more, more preferably 120,000 or more, and further preferably 150,000 or more. By making the resin composition of the present embodiment contain copolymer (A) and copolymer (B), there is a tendency for the low dielectric constant and low dielectric dissipation factor of the resin composition of the present embodiment to be improved. On the other hand, regarding heat resistance, component (I): hardened resin is higher than copolymers (A) and (B). By setting the number average molecular weight (Mnb) of the copolymer (B) to 80,000 or more, the decrease in heat resistance of the resin composition caused by the addition of copolymers (A) and copolymers (B) can be suppressed, thereby ensuring the excellent heat resistance of the resin composition of the present embodiment. From the viewpoint of productivity, the upper limit of the number average molecular weight (Mnb) of the copolymer (B) is preferably 700,000 or less, more preferably 500,000 or less, and further preferably 300,000 or less. The number average molecular weight (Mnb) of the copolymer (B) can be measured by GPC. The number average molecular weight (Mnb) of the copolymer (B) can be controlled within the above numerical range by adjusting the conditions such as the amount of monomer added and the amount of polymerization initiator added in the polymerization step.

The copolymer (B) is not limited to the following, but preferably has a structure represented by the following general formula. (a1-b1) _o (a1-c1) _o a1-b1-a2 a1-c1-a2 a1-b1-c1 a1-c1-b1 a1-b1-c1-a2 a1-c1-b1-a2 a1-b1-c1-b2 a1-c1-b1-c2 a1-b1-a2-b2 a1-b1-a2-c1 a1-c1-a2-c2 a1-c1-a2-b1 [(a1-b1) _o ] _p -Z [(a1-c1) _o ] _p -Z (a1-b1-c1) _p -Z (a1-c1-b1) _p -Z

The copolymer (B) is more preferably a block copolymer of a structure represented by the general formula a1-b1-a2-b2, a1-b1-a2-c1, a1-c1-a2-b1, a1-c1-a2-c2, and more preferably a1-b1-a2-c1. When the copolymer (B) is a block copolymer of a structure represented by the general formula a1-b1-a2-b2, a1-b1-a2-c1, a1-c1-a2-b1, a1-c1-a2-c2, the resin composition of the present embodiment tends to have excellent copper adhesion. In the above general formula, a1, a2, b1, b2, c1, c2 represent polymer blocks (a1), (a2), (b1), (b2), (c1), (c2), respectively. o is an integer greater than 1, preferably an integer from 1 to 10, and more preferably an integer from 1 to 5. p is an integer greater than 2, preferably an integer from 2 to 11, and more preferably an integer from 2 to 8. Z represents a coupling agent residue. Here, the coupling agent residue refers to the residue after bonding of the coupling agent used for bonding between polymer blocks (b1) and between polymer blocks (c1).

The copolymer (B) is preferably obtained by sequential polymerization. The term "sequential polymerization" means sequential polymerization from the end of one side of the final target polymer structure to the end of the opposite side, and polymerization is performed without using a coupling reaction. According to sequential polymerization, a polymer with an asymmetric structure can be produced, so it is suitable for producing an asymmetric copolymer (B) such as a1-b1-a2-c1. In addition, when the copolymer (B) is formed by polymerization by coupling reaction, there is a case where an unintended uncoupled polymer is included, and it is possible that the copolymer (A) and the copolymer (B) are not obtained as designed. However, sequential polymerization is preferred in that it is difficult to produce components other than the target structure as by-products.

The vinyl aromatic monomer units in the polymer block (b) may be uniformly distributed or may be tapered. Furthermore, the vinyl aromatic monomer units may exist in a plurality of uniformly distributed portions and/or tapered portions. Furthermore, in the polymer block (b), a plurality of portions having different contents of the vinyl aromatic monomer units may coexist.

In the above general formulas representing copolymers (B), (a1) and (a2) are polymer blocks mainly composed of vinyl aromatic monomer units. (b1) and (b2) are random copolymer blocks containing vinyl aromatic monomer units and covalent diene monomer units. (c1) and (c2) are polymer blocks mainly composed of covalent diene monomer units.

(Relationship between the content of the polymer block mainly composed of vinyl aromatic monomer units in copolymer (A) and copolymer (B)) In the resin composition of the present embodiment, the difference (ΔBS) between the content (BSa) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in copolymer (A) and the content (BSb) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in copolymer (B) satisfies the following relationship. ΔBS＝｜BSa―BSb｜≦20 Moreover, ΔBS is preferably less than 15, and more preferably less than 10. When the above ΔBS satisfies the above relationship, the solubility of copolymer (A) and copolymer (B) relative to the varnish can be ensured. Since copolymer (B) has a relatively high molecular weight, it may be difficult to dissolve in varnish alone due to its molecular weight or structure. By setting ΔBS to a smaller value, it is possible to prevent the copolymer (B) from being difficult to dissolve in varnish. It is believed that the reason is that copolymer (A) has a low molecular weight and tends to be more soluble in varnish. Therefore, by satisfying |BSa-BSb|≦20, the compatibility between copolymer (A) and copolymer (B) becomes good, and copolymer (A) can act like a compatibilizer to help improve the solubility of copolymer (B) in varnish. ΔBS can be controlled within the above numerical range by adjusting the amount of monomers added in the polymerization steps of copolymer (A) and copolymer (B) and the polymerization time.

(Relationship between the number average molecular weights of copolymer (A) and copolymer (B)) The ratio (Mnb/Mna) of the number average molecular weight (Mnb) of the copolymer (B) to the number average molecular weight (Mna) of the copolymer (A) is preferably greater than 4, more preferably greater than 5, and further preferably greater than 6. When (Mnb/Mna) is greater than 4, the resin composition of the present embodiment tends to have excellent heat resistance.

(Average value of the content of vinyl aromatic monomer units in copolymers (A) and (B)) The average value of the content of vinyl aromatic monomer units in copolymers (A) and (B) is 40% by mass or less, preferably 10% to 40% by mass, more preferably 13% to 40% by mass, further preferably 17% to 40% by mass, further preferably 17% to 36% by mass. If the average value of the content of vinyl aromatic monomer units in copolymers (A) and (B) is 40% by mass or less, the resin composition of the present embodiment tends to show good dielectric properties. The content of vinyl aromatic monomer units in copolymers (A) and (B) may be the same or different. In different cases, the two can be set in such a way that the average value of the content of the vinyl aromatic monomer unit in the state of the total copolymer (A) and the copolymer (B) is less than 40 mass %, and the content of the vinyl aromatic monomer unit of the two polymers can be set in such a way that the weighted average of the added molecular weight and the mixing ratio is less than 40 mass %. From the viewpoint of improving the compatibility of the two copolymers, the content of the vinyl aromatic monomer unit, the vinyl bonding amount and the hydrogenation rate of the copolymer (A) and the copolymer (B) are preferably small. The average value of the content of the vinyl aromatic monomer unit of the copolymer (A) and the copolymer (B) can be controlled within the above-mentioned numerical range by adjusting the amount of monomer added in the polymerization step of the copolymer (A) and the copolymer (B).

(Average vinyl bonding content of copolymer (A) and copolymer (B)) The average vinyl bonding content (V) of the covalent diene monomer units of copolymer (A) and copolymer (B) is preferably 20% or more, more preferably 30% or more, and further preferably 40% or more. If the average vinyl bonding content (V) of the covalent diene monomer units of copolymer (A) and copolymer (B) is 20% or more, the copper adhesion of the resin composition of this embodiment tends to be improved.

The average vinyl bond content (V) in the covalent diene monomer units of the copolymer (A) and the copolymer (B) is preferably 85% or less, more preferably 75% or less, and further preferably 65% or less. If the average vinyl bond content (V) in the covalent diene monomer units of the copolymer (A) and the copolymer (B) is 85% or less, the resin composition of the present embodiment tends to have excellent long-term storage stability. The vinyl bond content of the copolymer (A) and the copolymer (B) may be the same or different. In different cases, the vinyl bond content of the two polymers may be set in a manner that provides a preferred vinyl bond content in the state of the total copolymer (A) and the copolymer (B).

(Average vinyl bond content (V) and average hydrogenation rate (H) of copolymers (A) and (B)) From the viewpoint of long-term storage stability of varnish, copolymers (A) and (B) are preferably hydrogenated copolymers, and preferably the average hydrogenation rate (H) (%) of unsaturated double bonds from the conjugated diene compound contained in the copolymer and the average vinyl bond content (V) (%) in the conjugated diene monomer units contained in copolymers (A) and (B) satisfy the following relationship. V + 10 ≦ H Here, the average hydrogenation rate (H) refers to the average hydrogenation rate of copolymers (A) and (B), which can be calculated by the following formula based on the results of NMR measurement. Average hydrogenation rate (H) = (hydrogenation rate of copolymer (A)) × (mass ratio of copolymer (A)) + (hydrogenation rate of copolymer (B)) × (mass ratio of copolymer (B)) The average vinyl bond content (V) is the average vinyl bond content of copolymer (A) and copolymer (B), and can be calculated by the following formula based on NMR measurement. Average vinyl bond content (V) = (vinyl bond content of copolymer (A)) × (mass ratio of copolymer (A)) + (vinyl bond content of copolymer (B)) × (mass ratio of copolymer (B)) Compared with the unsaturated bond formed by 1,4-addition of the conjugated diene, the reactivity of the hydrogenation reaction of the vinyl bond is higher. Therefore, when the average hydrogenation rate (H) of the copolymer (A) and the copolymer (B) satisfies the above formula, the double bonds of the vinyl bonds are substantially hydrogenated, thereby the resin composition of the present embodiment tends to have excellent long-term storage stability.

The average hydrogenation rate (H) of the copolymer (A) and the copolymer (B) can be controlled, for example, by the amount of the catalyst during hydrogenation, and the hydrogenation rate can be controlled, for example, by the amount of the catalyst during hydrogenation, the amount of hydrogen fed, the pressure and the temperature. The average hydrogenation rate (H) of the copolymer (A) and the copolymer (B) can be measured by a nuclear magnetic resonance device (NMR). The average vinyl bond content (V) of the copolymer (A) and the copolymer (B) can be controlled, for example, by adjusting the amount of the tertiary amine compound or the ether compound added and the polymerization temperature. The average vinyl bond content (V) of the copolymer (A) and the copolymer (B) can be measured by a nuclear magnetic resonance device (NMR).

When the copolymer (A) and the copolymer (B) have random copolymer blocks of vinyl aromatic monomer units and covalent diene monomer units, the mass ratio (RS) of the vinyl aromatic monomer units contained in the random copolymer blocks is preferably 30 mass % or less, more preferably 20 mass % or less, and further preferably 10 mass % or less. When the mass ratio (RS) of the vinyl aromatic monomer units contained in the random copolymer blocks of the copolymers (A) and (B) is 30 mass % or less, there is a tendency that the copolymers having random copolymer blocks, the resin compositions containing the above copolymers, and the cured products thereof have excellent copper adhesion.

(Relationship between the molecular weights of the polymer blocks mainly composed of vinyl aromatic monomer units of copolymers (A) and (B)) The ratio (MnS1/MnS2) of the molecular weight (MnS1) of the polymer blocks mainly composed of vinyl aromatic monomer units of copolymer (A) to the molecular weight (MnS2) of the polymer blocks mainly composed of vinyl aromatic monomer units of copolymer (B) is preferably 0.9 or less, more preferably 0.8 or less, and further preferably 0.7 or less. When (MnS1/MnS2) is 0.9 or less, the resin composition of the present embodiment tends to have excellent copper adhesion. Furthermore, (MnS1) and (MnS2) can be controlled by adjusting the amount of monomer added during polymerization. MnS1 and MnS2 are calculated by the following method. MnS1＝Mn1×BS1 MnS2＝Mn2×BS2÷f •BS1: The content of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (A) determined by proton nuclear magnetic resonance ( ¹ H-NMR) (mass %) •BS2: The content of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (B) determined by proton nuclear magnetic resonance ( ¹ H-NMR) (mass %) •f: The branching degree (Mn1) and (Mn2) of the copolymer (B) determined by the GPC-light scattering method with a viscosity detector can be measured by GPC using standard polystyrene as a calibration curve. (BS1) and (BS2) can be measured by NMR. (f) can be measured by the GPC-light scattering method with a viscosity detector. Furthermore, the specific measurement method is explained below.

Taking the case where the vinyl aromatic compound is styrene and the covalent diene compound is 1,3-butadiene as an example, the method of measuring the mass ratio (RS1) and (RS2) of the vinyl aromatic monomer unit in the random polymer block and the content (BS1) and (BS2) of the polymer block mainly composed of the vinyl aromatic monomer unit is specifically described. 1 ^H -NMR is measured using a sample prepared by dissolving 30 mg of each copolymer (A) and copolymer (B) in 1 g of deuterated chloroform, and the content (BS) of the polymer block mainly composed of the vinyl aromatic monomer unit (in this case, the styrene block) is calculated from the ratio of the cumulative value of the chemical shift of 6.9 ppm to 6.3 ppm to the total cumulative value. Styrene block strength (b-St strength) = (cumulative value of 6.9 ppm to 6.3 ppm)/2 Random styrene strength (r-St strength) = (cumulative value of 7.5 ppm to 6.9 ppm) - 3×(b-St) Ethylene-butene strength (EB strength) = total cumulative value - 3×{(b-St strength) + (r-St strength)}/8 Styrene block content (BS) = 104×(b-St strength) /[104×{(b-St strength) + (r-St strength)} + 56×(EB strength)] Mass ratio of styrene in random polymer blocks (RS) = 104×(r-St strength)/{104×(r-St strength) + 56×(EB strength)}

(Degree of branching (f) of copolymer (B)) The degree of branching (f) of copolymer (B) can be measured by GPC-light scattering method with viscosity detector. GPC-light scattering method with viscosity detector is carried out using copolymer (B) as a sample. Based on standard polystyrene, the absolute molecular weight (M) is calculated from the results of the light scattering detector and the RI detector, and the intrinsic viscosity ([η]) is calculated from the results of the RI detector and the viscosity detector. Then, the intrinsic viscosity ([η] ₀ ) serving as a reference is calculated by the following formula. [η] ₀ = a×M ^b a = -0.788 + 0.421×(content of vinyl aromatic monomer units of copolymer (B)) -0.342×(RS2) -0.197×(BS2) b = 1.601 - 0.081×(content of vinyl aromatic monomer units of copolymer (B)) + 0.064×(RS2) + 0.039×(BS2) RS2: mass ratio of vinyl aromatic monomer units in random polymer blocks of copolymer (B) BS2: content of polymer blocks mainly composed of vinyl aromatic monomer units of copolymer (B) determined by proton nuclear magnetic resonance ( ¹ H-NMR) M: absolute molecular weight of copolymer (B) Then, the intrinsic viscosity ([η] ) of copolymer (B) and the intrinsic viscosity ([η] ₀ ) is used to calculate the contraction factor g. Contraction factor (g) = [η]/[η] ₀ Then, using the obtained contraction factor (g), the branching degree (f) defined as g = f/{(f+1)(f+2)}(f≧2) is calculated.

(Methods for producing copolymers (A) and (B)) As methods for producing copolymers (A) and (B), for example, methods described in Japanese Patent Publication No. 36-19286, Japanese Patent Publication No. 43-17979, Japanese Patent Publication No. 46-32415, Japanese Patent Publication No. 49-36957, Japanese Patent Publication No. 48-2423, Japanese Patent Publication No. 48-4106, Japanese Patent Publication No. 51-49567, Japanese Patent Laid-Open No. 59-166518, etc. can be cited, but the present invention is not limited thereto.

Furthermore, as a method for producing the copolymer (A) and the copolymer (B), the following methods can be cited as examples: (1) subjecting the copolymer (A) and the copolymer (B) to solution polymerization respectively, and mixing the solutions containing the polymers; (2) subjecting the copolymer (A) and the copolymer (B) to desolventization and decatalysis respectively, and then mixing the copolymers; (3) adding a polymerization initiator in two stages during the polymerization reaction; (4) adding a 2-hydroxy-2-nitropropene in the polymerization reaction relative to the 2-hydroxy-2-nitropropene; (5) after the polymerization reaction, a modifier equivalent to the molar amount of the active ends or a protic reagent such as an alcohol as a polymerization terminator is added to terminate the reaction of a part of the active ends, and then a polymerization initiator and a monomer are newly added to the solution to carry out polymerization, but it is not limited to the above. In the method (1) above, any of the following methods can also be applied: a method of mixing the polymerization solutions of the copolymer (A) and the copolymer (B) before the hydrogenation reaction and then carrying out the hydrogenation reaction, and a method of carrying out the hydrogenation reaction on the copolymer (A) and the copolymer (B) separately and then mixing the solutions. Furthermore, the mixing ratio of copolymer (A) and copolymer (B) can be controlled by adjusting the concentration of each polymerization solution and the mixing amount of the solutions. In the method (3) above, the mixing ratio of copolymer (A) and copolymer (B) can be arbitrarily controlled by adjusting the feed rate of the vinyl aromatic compound and the covalent diene compound, the amount of the polymerization initiator added in the two stages, and the timing of adding the polymerization initiator in the second stage. In the method (4) above, the mixing ratio and structure of copolymer (A) and copolymer (B) can be arbitrarily controlled by adjusting the feed rate and feed composition of the vinyl aromatic compound and the covalent diene compound, the amount of the modifier or polymerization terminator added in the middle and the timing of adding. Copolymer (A) is a low molecular weight body, and the molecules are less entangled with each other. Therefore, the method of mixing before desolventizing as in the methods (1), (3), (4), and (5) above can carry out desolventizing and final processing steps at a high rate. The methods (3) and (4) above can produce copolymer (A) and copolymer (B) at the same time, and compared with the case of producing copolymer (A) and copolymer (B) separately, the production steps can be reduced, thereby improving production efficiency.

When a styrene-butadiene copolymer is produced by batch polymerization using a tank reactor equipped with a stirring device and a jacket, if the block structure of the copolymer (A) is set to d-e and the block structure of the copolymer (B) is set to a1-b1-a2-c1, it is preferred that the c1 block and the e block have the same structure and the same molecular weight, and it is preferred that the a2 block and the d block are composed of the same vinyl aromatic compound, and it is preferred that the molecular weight of the a2 block is greater than that of the d block. Furthermore, when the polymerization is carried out using the method (3), the timing of adding the initiator in the second stage depends on the molecular weight ratio of the a2 block to the d block, and is preferably the timing when the polymerization conversion rate of the vinyl aromatic compound in the a2 block becomes 100×(molecular weight of the d block)/(molecular weight of the a2 block) (%).

<Differentiation between copolymer (A) and copolymer (B)> The resin composition of this embodiment includes two components, copolymer (A) and copolymer (B), so the GPC graph has two or more peaks. The so-called copolymer (A) refers to all components with a number average molecular weight of 40,000 or less.

The copolymer before hydrogenation is not limited to the following, and can be obtained, for example, by the following method: using a polymerization initiator such as an organic alkali metal compound in a hydrocarbon solvent, and using a specified monomer to perform living anionic polymerization. The hydrocarbon solvent is not particularly limited, and examples thereof include: aliphatic hydrocarbons such as n-butane, isobutane, n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclohexane, cycloheptane, and methylcycloheptane; aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene, etc.

As a polymerization initiator, an organic alkali metal compound known to have anionic polymerization activity with respect to a conjugated diene compound and a vinyl aromatic compound can be generally used. For example, aliphatic alkali metal compounds with 1 to 20 carbon atoms, aromatic alkali metal compounds with 1 to 20 carbon atoms, organic amino alkali metal compounds with 1 to 20 carbon atoms, etc. can be cited. As the alkali metal contained in the polymerization initiator, lithium, sodium, potassium, etc. can be cited, but it is not limited to them. Furthermore, the alkali metal can contain one or more kinds in one molecule. As polymerization initiators, for example, n-propyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, n-pentyl lithium, n-hexyl lithium, benzyl lithium, phenyl lithium, tolyl lithium, the reaction product of diisopropenylbenzene and sec-butyl lithium, and further the reaction product of divinylbenzene and sec-butyl lithium and a small amount of 1,3-butadiene, etc. can be cited, but it is not limited to these. Furthermore, lithium compounds with one to several molecules of isoprene monomer inserted in order to improve its solubility, alkyl lithium containing silaneoxy groups such as 1-(tert-butyldimethylsiloxy)hexyl lithium disclosed in U.S. Patent No. 5,708,092, lithium amides such as alkyl lithium containing amine groups disclosed in U.S. Patent No. 5,527,753, lithium diisopropylamide, and lithium bis(trimethylsilyl)amide, can also be used.

The amount of the lithium compound used as a polymerization initiator depends on the molecular weight of the target copolymer, and is preferably 0.005 to 6.4 phm (per 100 parts by weight of the monomer), and more preferably 0.005 to 2.6 phm.

When a covalent diene compound and a vinyl aromatic compound are copolymerized using an organic alkali metal compound as a polymerization initiator, a tertiary amine compound or an ether compound may be added in order to adjust the content of the vinyl bond (1,2-bond or 3,4-bond) incorporated in the covalent diene monomer unit of the copolymer or to adjust the random copolymerizability of the covalent diene compound and the vinyl aromatic compound.

The tertiary amine compound is not particularly limited, and examples thereof include compounds represented by the following formula. R1R2R3N (wherein R1, R2, and R3 are alkyl groups having 1 to 20 carbon atoms or alkyl groups having a tertiary amine group) Examples of such compounds include trimethylamine, triethylamine, tributylamine, N,N-dimethylaniline, N-ethylpiperidine, N-methylpyrrolidine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetraethylethylenediamine, 1,2-dipiperidylethane, trimethylaminoethylpiperidin, N,N,N',N'',N''-pentamethylethylenetriamine, N,N'-dioctyl-p-phenylenediamine, etc., but are not limited thereto. Among these, N,N,N',N'-tetramethylethylenediamine is preferred.

Furthermore, the ether compound may be a linear ether compound or a cyclic ether compound. As the linear ether compound, for example, dimethyl ether, diethyl ether, diphenyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether and other dialkyl ether compounds of ethylene glycol, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether and other dialkyl ether compounds of diethylene glycol, etc. Furthermore, as the cyclic ether compound, for example, tetrahydrofuran, dioxane, 2,5-dimethyloxycyclopentane, 2,2,5,5-tetramethyloxycyclopentane, 2,2-bis(2-oxycyclopentyl)propane, alkyl ethers of furfuryl alcohol and the like may be cited.

The usage amount of the tertiary amine compound or ether compound relative to the polymerization initiator of the above-mentioned organic alkali metal compound is preferably 0.1-4 (mole/1 mol of alkali metal), and more preferably 0.2-3 (mole/1 mol of alkali metal).

Sodium alkoxide may coexist during the copolymerization in the production steps of copolymer (A) and copolymer (B). Sodium alkoxide is not limited to the following, and for example, compounds represented by the following formulas can be cited. Sodium alkoxide having an alkyl group with 3 to 6 carbon atoms is particularly preferred, and sodium tert-butoxide and sodium tert-pentoxide are more preferred. NaOR (wherein R is an alkyl group with 2 to 12 carbon atoms) The amount of sodium alkoxide used in the polymerization step of copolymers (A) and (B) relative to the vinyl bond amount adjuster (tertiary amine compound or ether compound) is preferably 0.01 or more and less than 0.1 (molar ratio), more preferably 0.01 or more and less than 0.08 (molar ratio), further preferably 0.03 or more and less than 0.08 (molar ratio), further preferably 0.04 or more and less than 0.06 (molar ratio). If the amount of sodium alkoxide is within the range, there is a tendency to produce a copolymer having a copolymer block containing a conjugated diene monomer unit having a high vinyl bonding amount and a polymer block mainly composed of a vinyl aromatic monomer unit having a narrow molecular weight distribution with a high productivity.

The method of copolymerizing the covalent diene compound and the vinyl aromatic compound using an organic alkali metal compound as a polymerization initiator is not particularly limited, and may be batch polymerization, continuous polymerization, or a combination thereof. The polymerization temperature is not particularly limited, and is usually 0 to 180°C, preferably 30 to 150°C. The time required for polymerization varies depending on the conditions, but is usually within 48 hours, preferably 0.1 to 10 hours. In addition, it is preferred to perform the polymerization in an inert gas atmosphere such as nitrogen. Regarding the polymerization pressure, it can be performed within the range of sufficient pressure to maintain the monomer and the solvent in the liquid phase within the above-mentioned polymerization temperature range, and there is no particular limitation.

Furthermore, a coupling reaction may be carried out by adding a necessary amount of a difunctional or higher coupling agent at the end of the polymerization. The difunctional or higher coupling agent is not particularly limited, and a known one may be used. Examples of the difunctional coupling agent include, but are not limited to, dihalogen compounds such as dimethyldichlorosilane and dimethyldibromosilane, acid esters such as methyl benzoate, ethyl benzoate, phenyl benzoate, and phthalates. Examples of the polyfunctional coupling agent having three or more functional groups include, but are not limited to: 1,1,1,2,2-pentachloroethane, perchloroethane, pentachlorobenzene, perchlorobenzene, octabromodiphenyl ether, decabromodiphenyl ether, trivalent or higher polyols, epoxidized soybean oil, polyepoxy compounds such as diglycidyl bisphenol A, di- to hexafunctional epoxy-containing compounds, carboxylates, polyvinyl compounds such as divinylbenzene, silicon halides represented by the formula R1 _{(4 - n) SiXn} (wherein R1 represents a alkyl group having 1 to 20 carbon atoms, X represents a halogen, and n represents an integer of 3 or 4), and tin halides. Examples of silicon halides include, but are not limited to, methyltrichlorosilane, tert-butyltrichlorosilane, silicon tetrachloride, and bromides thereof. Examples of tin halides include, but are not limited to, polyvalent halogen compounds such as methyltin trichloride, tert-butyltin trichloride, and tin tetrachloride. In addition, dimethyl carbonate or diethyl carbonate may also be used.

Copolymer (A) and copolymer (B) may also be obtained by subjecting the active end of the block copolymer obtained by the above-mentioned method to an addition reaction with a modifier that generates an atomic group containing a functional group. Examples of the atomic group containing a functional group include an atomic group containing at least one functional group selected from the group consisting of the following groups: hydroxyl group, carbonyl group, thiocarbonyl group, acyl halide group, anhydride group, carboxyl group, thiocarboxyl group, aldehyde group, thialdehyde group, carboxylate group, amide group, sulfonic acid group, sulfonate group, phosphoric acid group, phosphoric acid ester group, amino group, imino group, nitrile group, pyridine group, quinoline group, epoxy group, thioepoxy group, sulfide group, isocyanate group, isothiocyanate group, silyl halide group, silanol group, alkoxysilyl group, tin halide group, alkoxytin group, and phenyltin group, but are not limited to these.

Examples of modifiers that generate functional group-containing atomic groups include tetraglycidyl-m-xylylenediamine, tetraglycidyl-1,3-diaminomethylcyclohexane, ε-caprolactone, δ-valerolactone, 4-methoxybenzophenone, γ-glycidyloxyethyltrimethoxysilane, γ-glycidyloxypropyltrimethoxysilane, γ-glycidyloxypropyldimethylphenoxysilane, bis(γ-glycidyloxypropyl)methylpropoxysilane, 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, N,N'-dimethylpropylurea, N-methylpyrrolidone, etc., but are not limited to them. The amount of the modifier added is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, and further preferably 0.3 to 10 parts by mass relative to 100 parts by mass of the copolymer before modification. The temperature of the addition reaction of the modifier is preferably 0 to 150°C, more preferably 20 to 120°C. The time required for the modification reaction varies depending on the modification reaction conditions, preferably within 24 hours, more preferably 0.1 to 10 hours.

The copolymer (A) is preferably produced by performing a hydrogenation step after the above-mentioned polymerization step or after the above-mentioned modification step. The hydrogenation catalyst used to produce the copolymer (A) is not particularly limited, and for example, the hydrogenation catalyst described in Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Patent Publication No. 1-37970, Japanese Patent Publication No. 1-53851, Japanese Patent Publication No. 2-9041 can be used. As a preferred hydrogenation catalyst, a titanocene compound and/or a mixture with a reducing organic metal compound can be cited. The titanium cyclopentadienyl compound is not particularly limited, and examples thereof include compounds described in Japanese Patent Laid-Open No. 8-109219. Specifically, examples thereof include compounds having at least one ligand having a (substituted) cyclopentadienyl structure, an indenyl structure, and a fluorenyl structure, such as biscyclopentadienyl titanium dichloride and monopentamethylcyclopentadienyl titanium trichloride. The reducing organic metal compound is not particularly limited, and examples thereof include organic alkali metal compounds such as organic lithium, organic magnesium compounds, organic aluminum compounds, organic boron compounds, and organic zinc compounds. The reaction temperature of the hydrogenation reaction is usually 0 to 200°C, preferably 30 to 150°C. The pressure of hydrogen used in the hydrogenation reaction is preferably 0.1 to 15 MPa, more preferably 0.2 to 10 MPa, and further preferably 0.3 to 5 MPa. The reaction time of the hydrogenation reaction is usually 3 minutes to 10 hours, preferably 10 minutes to 5 hours. Furthermore, the hydrogenation reaction can be carried out by a batch process, a continuous process, or a combination thereof.

The copolymer (B) is preferably produced by performing a hydrogenation step after the above-mentioned polymerization step or after the above-mentioned modification step. The hydrogenation catalyst used to produce the copolymer (B) is not particularly limited, and for example, the hydrogenation catalyst described in Japanese Patent Publication No. 42-8704, Japanese Patent Publication No. 43-6636, Japanese Patent Publication No. 63-4841, Japanese Patent Publication No. 1-37970, Japanese Patent Publication No. 1-53851, Japanese Patent Publication No. 2-9041, etc. can be used. As a preferred hydrogenation catalyst, a titanocene compound and/or a mixture with a reducing organic metal compound can be cited. The titanium cyclopentadienyl compound is not particularly limited, and examples thereof include compounds described in Japanese Patent Laid-Open No. 8-109219. Specifically, examples thereof include compounds having at least one ligand having a (substituted) cyclopentadienyl structure, an indenyl structure, and a fluorenyl structure, such as biscyclopentadienyl titanium dichloride and monopentamethylcyclopentadienyl titanium trichloride. The reducing organic metal compound is not particularly limited, and examples thereof include organic alkali metal compounds such as organic lithium, organic magnesium compounds, organic aluminum compounds, organic boron compounds, and organic zinc compounds. The reaction temperature of the hydrogenation reaction is usually 0 to 200°C, preferably 30 to 150°C. The pressure of hydrogen used in the hydrogenation reaction is preferably 0.1 to 15 MPa, more preferably 0.2 to 10 MPa, and further preferably 0.3 to 5 MPa. The reaction time of the hydrogenation reaction is usually 3 minutes to 10 hours, preferably 10 minutes to 5 hours. Furthermore, the hydrogenation reaction can be carried out by a batch process, a continuous process, or a combination thereof.

Catalyst residues can also be removed from the reaction solution after the hydrogenation step as needed. The polymerization initiator used in the production of hydrogenated copolymers by anion living polymerization, the compound containing metal atoms in the hydrogenation catalyst in the above-mentioned hydrogenation reaction, reacts with moisture in the air in the desolventizing step, etc., to generate a specified metal compound and tends to remain in the hydrogenated copolymer. If the resin composition of the present embodiment and its cured product contain such compounds, there is a tendency for the dielectric constant and dielectric dissipation factor to increase, and there is a tendency for ion migration to occur easily in electronic material applications. Examples of the residual metal compounds include: compounds of metals contained in polymerization initiators and hydrogenation catalysts, such as titanium oxide, amorphous titanium oxide, orthotitanium acid or metatitanium acid, titanium hydroxide, nickel hydroxide, nickel monoxide, lithium oxide, lithium hydroxide, cobalt oxide, cobalt hydroxide, etc., and composite oxides of atoms such as lithium titanate, barium titanate, strontium titanate, nickel titanate, nickel-iron oxide, etc. and foreign metals. From the perspective of the aforementioned low dielectric constant, low dielectric loss factor, and difficulty in generating ion migration, the residual amount of metal compounds in the copolymers (A) and (B) is preferably less than 150 ppm, more preferably less than 130 ppm, further preferably less than 100 ppm, and further preferably less than 90 ppm, in terms of residual metal amount. Specific residual metals generally include Ti, Ni, Li, Co, etc.

As a method for reducing the amount of residual metal in the resin composition and its cured product of the present embodiment, previously known methods can be applied without particular limitation. For example, the following methods can be cited: after the hydrogenation reaction of the copolymers (A) and (B), water and carbon dioxide are added to neutralize the hydrogenation catalyst residue; in addition to water and carbon dioxide, an acid is added to neutralize the hydrogenation catalyst residue. Specifically, the method described in Japanese Patent Application No. 2014-557427 can be applied. Even if such metal removal methods are used, since water containing hydroxides of metal compounds is mixed in the desolventizing step of the copolymers (A) and (B), it usually contains 1 to 15 ppm. Therefore, it is preferred to remove 20% or more of the amount of metal added to the copolymers (A) and (B), more preferably 30% or more, further preferably 40% or more, further preferably 50% or more, further preferably 60% or more.

Furthermore, the residual metal content in the copolymers (A) and (B) can be reduced by reducing the amount of the polymerization initiator and the hydrogenation catalyst added. However, if the amount of the polymerization initiator is reduced, the molecular weight of the copolymers (A) and (B) increases. If the molecular weight of the copolymers (A) and (B) is out of the range of the molecular weight required for the resin composition of the present embodiment, the heat resistance of the cured product tends to decrease. Furthermore, if the amount of the hydrogenation catalyst is reduced during the hydrogenation reaction, the hydrogenation reaction time tends to be prolonged, the hydrogenation reaction temperature tends to be increased, and the productivity tends to be significantly reduced.

As a method for separating the copolymers (A) and (B) from the solvent, for example, the following methods can be cited: adding a polar solvent such as acetone or alcohol that becomes a poor solvent for the copolymers (A) and (B) to a solution of the copolymers (A) and (B) to precipitate the copolymers (A) and (B) for recovery; or placing the solution of the copolymers (A) and (B) in hot water under stirring and removing the solvent by steam stripping for recovery; directly heating the solution of the copolymers (A) and (B) to remove the solvent by distillation, but the method is not limited to the above.

For copolymer (A) and copolymer (B), antioxidants may be added during production so that the surface and/or the inside of the copolymer contain antioxidants. Furthermore, the following antioxidants may be added to the resin composition of the present embodiment described below.

Examples of antioxidants include, but are not limited to, phenolic antioxidants, phosphorus antioxidants, sulfur antioxidants, amine antioxidants, and the like. Specifically, 2,6-di-tert-butyl-4-methylphenol, 3-(4'-hydroxy-3',5'-di-tert-butyl-phenyl) propionate n-octadecyl ester, tetrakis-[methylene-3-(3',5'-di-tert-butyl-4'-hydroxyphenyl) propionate] methane], isocyanuric acid tris-(3,5-di-tert-butyl-4-hydroxybenzyl) ester, 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol), 3,9-bis[2-{3-(3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy}-1,1-di methylethyl]-2,4,8,10-tetraoxaspiro[5,5]undecane, triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylanilino)-1,3,5-triazine, pentaerythritol-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,2-thio-diethylenebis[3-(3,5 -di-tert-butyl-4-hydroxyphenyl) propionate], N,N'-hexamethylenebis(3,5-di-tert-butyl-4-hydroxyphenylpropionamide), 3,5-di-tert-butyl-4-hydroxybenzyl phosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tri(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, a mixture of bis(ethyl 3,5-di-tert-butyl-4-hydroxybenzylphosphonate) calcium and polyethylene wax (50%), octylated diphenylamine, 2,4-bis[(octylthio)methyl]-o-cresol, 3-(3,5-di-tert-butyl- 4-hydroxyphenyl) isooctyl propionate, 3,3-bis(3-tert-butyl-4-hydroxyphenyl) vinyl butyrate, 1,1,3-tris-(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 2-tert-butyl-6-(3'-tert-butyl-5'-methyl-2'-hydroxybenzyl)-4-methylphenyl acrylate, and 2-[1-(2-hydroxy-3,5-di-tert-pentylphenyl)-ethyl]-4,6-di-tert-pentylphenyl acrylate, etc. In addition, from the perspective of insulation reliability, the above antioxidants can also be used as particle adhesion inhibitors.

Examples of the polymerization terminator include, but are not limited to, water, various alcohols such as methanol, ethanol, isopropanol, 2-ethylhexanol, heptanol, and mixtures thereof.

The copolymer (B) and/or the copolymer (A) may also be granulated. They may be granulated individually or in the form of a mixture. As a method of granulation, for example, the following methods can be cited: extruding copolymer (B) and/or copolymer (A) in the form of strands from a single-screw or double-screw extruder, and cutting them in water by a rotary knife provided in front of a die nozzle; extruding copolymer (A) and/or (B) in the form of strands from a single-screw or double-screw extruder, cooling them with water or air, and then cutting them by a strand cutter; melting and mixing them by an open roll or a Banbury mixer, forming them into sheets by a roll, and then cutting the sheets into short strips, and then cutting them into cubic pellets by a pelletizer. In addition, the size and shape of the pellets of copolymer (B) and/or copolymer (A) are not particularly limited. In the particles of copolymer (B) and/or copolymer (A), a particle adhesion inhibitor may be formulated as needed for the purpose of preventing particle adhesion. As the particle adhesion inhibitor, for example, calcium stearate, magnesium stearate, zinc stearate, polyethylene, polypropylene, ethyl distearate, talc, amorphous silica, etc. can be cited, but it is not limited to them. As the particle adhesion inhibitor, from the viewpoint of ion migration, EBS, polyethylene, and polypropylene are preferred. As the preferred formulation amount of the particle adhesion inhibitor, it is 500 to 6000 ppm relative to the copolymer (A) and/or (B), and as a more preferred amount, it is 1000 to 5000 ppm. The particle adhesion prevention agent is preferably formulated in a state of being attached to the particle surface, and can also be contained inside the particle to a certain extent.

(Molecular weight distribution of copolymer (A), copolymer (B)) The molecular weight distribution (Mwa/Mna) of copolymer (A) is preferably 1.01 to 8.0, more preferably 1.01 to 6.0, and further preferably 1.01 to 5.0. If the molecular weight distribution is within the above range, the resin composition of the present embodiment tends to have excellent heat resistance. Furthermore, the shape of the molecular weight distribution of copolymer (A) measured by GPC is not particularly limited, and may be a multi-peak molecular weight distribution having two or more peaks, or may be a single-peak molecular weight distribution having one peak. Furthermore, the weight average molecular weight (Mwa) and molecular weight distribution [Mwa/Mna; ratio of weight average molecular weight (Mwa) to number average molecular weight (Mna)] of the copolymer (A) can be obtained by using a calibration curve (prepared using the peak molecular weight of standard polystyrene) obtained by measuring the molecular weight of the peak of the chromatogram measured by GPC in the method described in the following embodiment.

The molecular weight distribution (Mwb/Mnb) of the copolymer (B) is preferably 1.01 to 8.0, more preferably 1.01 to 6.0, and further preferably 1.01 to 5.0. If the molecular weight distribution is within the above range, the resin composition of the present embodiment tends to have excellent heat resistance. Furthermore, the shape of the molecular weight distribution of the copolymer (B) measured by GPC is not particularly limited, and may be a multi-peak molecular weight distribution having two or more peaks, or may be a single-peak molecular weight distribution having one peak. Furthermore, the weight average molecular weight (Mwb) and molecular weight distribution [Mwb/Mnb; ratio of weight average molecular weight (Mwb) to number average molecular weight (Mnb)] of the copolymer (B) can be obtained by using a calibration curve (prepared using the peak molecular weight of standard polystyrene) obtained by measuring the molecular weight of the peak of the chromatogram measured by GPC in the method described in the following examples.

(Mass ratio of copolymer (A) to copolymer (B)) From the perspective of productivity, in the resin composition of this embodiment, the mass ratio (A)/(B) of the content of the copolymer (A) to the copolymer (B) is preferably 5/95 to 70/30, more preferably 10/90 to 60/40, and further preferably 15/85 to 50/50.

(Content of copolymer (A) and copolymer (B)) The total content of copolymer (A) and copolymer (B) in the resin composition of the present embodiment is not particularly limited, but is preferably 5 parts by mass or more and 60 parts by mass or less relative to 100 parts by mass of the resin solid content of the resin composition of the present embodiment. In addition, from the perspective of imparting softness, low dielectric constant, and low dielectric loss tangent to the resin composition of the present embodiment, the lower limit of the total content of copolymer (A) and copolymer (B) is preferably 6 parts by mass or more, and further preferably 8 parts by mass or more. Furthermore, from the viewpoint of suppressing the decrease in glass transition temperature, suppressing the increase in thermal expansion coefficient, and suppressing viscosity deterioration of the resin composition of the present embodiment, the upper limit of the combined content of copolymer (A) and copolymer (B) is preferably 50 parts by mass or less, and further preferably 40 parts by mass or less. The so-called resin solid content refers to the component obtained by removing fillers and solvents from the resin composition.

(Components constituting the resin composition) The resin composition of the present embodiment comprises the copolymer (A) and the copolymer (B) described above, and at least one component selected from the group consisting of the following components (I) to (III). Component (I): hardened resin (excluding copolymer (A) and copolymer (B)) Component (II): free radical initiator Component (III): hardener (excluding component (I)) From the perspective of the crack resistance of the resin composition of the present embodiment, it is preferred to include component (I): hardened resin.

<Component (I): Curing resin (excluding copolymer (A) and copolymer (B))> The resin composition of this embodiment may also contain the above-mentioned component (I) curing resin (excluding copolymer (A) and copolymer (B)) for the purpose of imparting heat resistance and adhesion to the substrate, within the range of not impairing the dielectric properties of the cured product. The component (I) curing resin has the effect of improving strength or heat resistance by crosslinking in the resin composition of this embodiment. By making the curing resin have a polar group, there is a tendency that the resin composition of this embodiment and the cured product have excellent heat resistance. As component (I): the curing resin (excluding copolymer (A) and copolymer (B)), from the viewpoint of heat resistance and adhesiveness of the resin composition of this embodiment, it is preferably at least one selected from the group consisting of epoxy resin, polyimide resin, polyphenylene ether resin, liquid crystal polyester resin, and fluorine resin, and more preferably epoxy resin, polyimide resin, and polyphenylene ether resin.

From the viewpoint of heat resistance of the resin composition of the present embodiment, the polyimide resin as component (I) may be any resin that has an imide bond in the repeating unit and is referred to as a polyimide resin. For example, a conventional polyimide structure obtained by polycondensing tetracarboxylic acid or its dianhydride with diamine (imide bond) can be cited, but the present invention is not limited thereto. From the viewpoint of curability, it is preferred that the polyimide structure has an unsaturated group at the end. As the above-mentioned polyimide resin having an unsaturated group at the end, for example, cis-butylene diimide type polyimide resin, nylonitrile type polyimide resin, allyl nylonitrile type polyimide resin, etc. can be cited. As the above-mentioned tetracarboxylic acid or its dianhydride, for example, aromatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, aliphatic tetracarboxylic dianhydride, etc. can be cited, but it is not limited to them. These can be used alone or in combination of two or more. As the above-mentioned diamine, for example, aromatic diamines, alicyclic diamines, aliphatic diamines, etc., which are generally used in the synthesis of polyimide, can be cited, but it is not limited to them. These can be used alone or in combination of two or more. Furthermore, from the perspective of lowering the dielectric constant and dielectric loss factor of the cured product of the resin composition of the present embodiment, at least one of the above-mentioned tetracarboxylic acids or their dianhydrides and diamines may have one or more functional groups selected from the group consisting of fluorine, trifluoromethyl, hydroxyl, sulfonyl, carbonyl, heterocyclic, long-chain alkyl, allyl, etc. In addition, component (I) may also use commercially available polyimide resins, for example, Neopulim (registered trademark) C-3650 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), Neopulim C-3G30 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), Neopulim C-3450 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), Neopulim P500 (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name), BT (bis(butylene) diimide-tris(iota)) resin (manufactured by Mitsubishi Gas Chemical Co., Ltd.), JL-20 (manufactured by Shin Nippon Rika Co., Ltd., trade name) (silicon dioxide may also be contained in the varnish of these polyimide resins), Rica Coat SN20 and Rica Coat SN20 manufactured by Shin Nippon Rika Co., Ltd. PN20, Pyre-ML manufactured by I.S.T., UPIA-AT, UPIA-ST, UPIA-NF, UPIA-LB manufactured by Ube Industries, PIX-1400, PIX-3400, PI2525, PI2610, HD-3000, AS-2600 manufactured by Hitachi Chemical, HPC-5000, HPC-5012, HPC-1000, HPC-5020, HPC-3010, HPC-6000, HPC-9000, HCI-7000, HCI-1000S, HCI-1200E, HCI-1300 manufactured by Showa Denko Co., Ltd., BMI-2300 manufactured by Yamato Chemical Industries Co., Ltd., MIR-3000 manufactured by Shin Nippon Kayaku Co., Ltd.

The polyphenylene ether resin as component (I) only needs to belong to the category of polyphenylene ether resins and contain phenylene ether units as repeating structural units. It may be a homopolymer having phenylene ether units, or a polymer containing other structural units other than phenylene ether units. As the above-mentioned homopolymer having phenylene ether units, there is no particular restriction on whether the phenylene groups in the phenylene units have substituents. As substituents, for example, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl and other acryl groups, cyclohexyl and other cyclic alkyl groups, vinyl, allyl, isopropenyl, 1-butenyl, 1-pentenyl, p-vinylphenyl, p-isopropenylphenyl, m-vinylphenyl, m-isopropenylphenyl, o-vinylphenyl, o-isopropenylphenyl, p-vinylbenzyl, p-isopropenylbenzyl, m-vinylbenzyl, m-isopropenylbenzyl, o-vinylbenzyl, o-isopropenylbenzyl, p-vinylphenylvinyl, p-vinylphenylpropenyl, p-vinylphenylbutenyl, m-vinylphenylvinyl, m-vinylphenylpropenyl, m-vinylphenylbutenyl, o-vinylphenylvinyl, o-vinylphenylpropenyl, o-vinylphenylpropenyl, o-vinylphenyl unsaturated bond-containing substituents such as alkenylphenylbutenyl, methacryl, acryl, 2-ethylacryl, 2-hydroxymethacryl, hydroxyl, carboxyl, carbonyl, thiocarbonyl, acyl halide, anhydride, carboxylic acid, thiocarboxylic acid, aldehyde, thialdehyde, carboxylate, amide, sulfonic acid, sulfonate, phosphoric acid, phosphoric acid ester, amine, imine, nitrile, pyridyl, quinolyl, epoxide, thio From the perspective of the curability of the resin composition of the present embodiment, the substituent containing a functional group such as an epoxy group, a thiol group, an isocyanate group, an isothiocyanate group, a silyl halide group, a silanol group, an alkoxysilyl group, a tin halide group, a boric acid group, a boron-containing group, a borate group, an alkoxytin group, and a phenyltin group is preferably a polar group with a predetermined purpose for the purpose of having free radical reactivity and/or reactivity with the following component (III): a curing agent. From the perspective of the curability of the resin composition of the present embodiment, the molecular weight of the polyphenylene ether resin is preferably 100,000 or less, more preferably 50,000 or less, and further preferably 10,000 or less. In addition, polyphenylene ether resins can be linear, cross-linked or branched.

The liquid crystal polyester resin as component (I) can be any polyester that forms an anisotropic melt phase and belongs to the category of liquid crystal polyester resins. For example, "X7G" manufactured by Eastman Kodak, Xyday manufactured by Dartco, Econol manufactured by Sumitomo Chemical, Vectra manufactured by Celanese, etc.

The epoxy resin as component (I) may be any resin that falls within the category of epoxy resins. From the viewpoint of the strength of the resin composition of the present embodiment, it is preferred that the epoxy resin has two or more epoxy groups in one molecule. The epoxy resin may be used alone or in combination of two or more. Examples of the epoxy resin include bixylenol epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol AF epoxy resin, dicyclopentadiene epoxy resin, trisphenol epoxy resin, naphthol novolac epoxy resin, phenol novolac epoxy resin, tert-butyl-ophthalic acid epoxy resin, naphthalene epoxy resin, naphthol epoxy resin, Resins, anthracene-type epoxy resins, glycidylamine-type epoxy resins, glycidyl ester-type epoxy resins, cresol novolac-type epoxy resins, biphenyl-type epoxy resins, alicyclic epoxy resins, heterocyclic epoxy resins, epoxy resins containing spirocyclic rings, cyclohexane-type epoxy resins, cyclohexanedimethanol-type epoxy resins, naphthyl ether-type epoxy resins, trihydroxymethyl-type epoxy resins, tetraphenylethane-type epoxy resins, etc.

Furthermore, from the viewpoint of reactivity, when an epoxy resin is used as component (I), the resin composition of the present embodiment preferably contains the following component (III): a hardener. As the polar group of the component (III): curing agent, for example, there can be mentioned a carboxyl group, an imidazole group, a hydroxyl group, an amine group, a thiol group, a benzothiol group, and a carbodiimide group. In terms of reactivity, a carboxyl group, an imidazole group, a hydroxyl group, a benzothiol group, and a carbodiimide group are preferred. In terms of the low dielectric constant and low dielectric dissipation factor of the resin composition and the cured product of the present embodiment, a hydroxyl group, a carboxyl group, an imidazole group, a benzothiol group, and a carbodiimide group are more preferred. A hydroxyl group, a carboxyl group, and a carbodiimide group are further preferred.

Furthermore, two or more polar resins with different free radical reactivity may be used as component (I). In this case, from the perspective of the curability of the resin composition of the present embodiment, the following component (II): free radical initiator and the following component (III): curing agent may be used alone or in combination. For example, when a butylene diimide type polyimide resin having excellent free radical reactivity and a bisphenol A epoxy resin having no free radical reactivity are used as component (I), from the perspective of the curability of the resin composition of the present embodiment, the additional component (II): free radical initiator and the component (III): curing agent may be used in combination.

Furthermore, when a high melting point and high rigidity polar resin is used as component (I), the following component (III): a hardener may not be included. Examples of high melting point and high rigidity polar resins include liquid crystal polyester resins, polytetrafluoroethylene and other fluorine resins. By making component (I) high melting point and high rigidity, the resin composition of the present embodiment tends to have the heat resistance and/or strength required for practical use even when the following component (III): a hardener is not included.

From the viewpoint of heat resistance, the content of component (I) in the resin composition of the present embodiment is preferably 10 to 90 parts by mass, more preferably 15 to 85 parts by mass, and further preferably 20 to 80 parts by mass, relative to 100 parts by mass of the resin solid content of the resin composition of the present embodiment. The so-called resin solid content refers to the component obtained by removing the filler and the solvent from the resin composition.

<Component (II): Free radical initiator> As component (II): free radical initiator, a previously known one can be used, and for example, a thermal free radical initiator can be cited as a preferred one. Examples of the thermal radical initiator include hydrogen peroxides such as diisopropylbenzene hydroperoxide (Percumyl P), isopropylbenzene hydroperoxide (Percumyl H), and tert-butyl hydroperoxide (Perbutyl H); α,α-bis(tert-butylperoxy-m-isopropyl)benzene (Perbutyl P), diisopropylbenzene peroxide (Percumyl D), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane (Perhexa 25B), tert-butyl isopropyl peroxide (Perbutyl C), di-tert-butyl peroxide (Perbutyl D), 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexyne-3 (Perhexyne 25B), tert-butyl peroxy-2-ethylhexanoate (Perbutyl O) and other dialkyl peroxides; ketone peroxides; peroxy ketal such as 4,4-di-(tert-butylperoxy) valerate (Perhexa V); diacyl peroxides; peroxydicarbonates; organic peroxides such as peroxyesters; azo compounds such as 2,2-azobisisobutylnitrile, 1,1'-(cyclohexane-1-carbonitrile), 2,2'-azobis(2-cyclopropylpropionitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), etc., but are not limited to these. These may be used alone or in combination of two or more.

When the above-mentioned component (I): curing resin is a resin with free radical reactivity, the amount of component (II): free radical initiator can be arbitrarily adjusted according to the reactivity or component (II): free radical initiator can be omitted. The so-called resin with free radical reactivity as component (I) includes, for example, a homopolymer of a compound containing at least one vinyl group and/or a halogen element in the polymer and/or a copolymer with any compound. From the perspective of the low dielectric constant and low dielectric dissipation factor of the resin composition and the cured product of the present embodiment, it is preferred that the above-mentioned homopolymer and/or copolymer have a vinyl group. The so-called vinyl group may be a polymer containing repeating units having a vinyl group, or may be a polymer having a vinyl group obtained by reacting a compound having a vinyl group and a polar group with each polar group of a resin having a polar group. Examples of the compounds having a vinyl group and a polar group include: (meth)acrylic acid (in this specification, "(meth)acryloyl" means "methacryloyl or acryl"), vinyl monomers containing carboxyl groups such as maleic acid, monoalkyl maleate, and fumaric acid, vinyl monomers containing sulfonyl groups such as vinyl sulfonic acid, (meth)allyl sulfonic acid, methylvinyl sulfonic acid, and styrene sulfonic acid, hydroxystyrene, N-hydroxymethyl (meth)acrylamide, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and vinyl monomers containing hydroxyl groups such as 2-hydroxyethyl (meth)acryloyl phosphate, phenyl-2-acryloyloxyethyl phosphate, and 2-acryloyloxyethylphosphonic acid. vinyl monomers containing hydroxyl groups, hydroxystyrene, N-hydroxymethyl (meth)acrylamide, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, polyethylene glycol (meth)acrylate, 1-butene-3-ol and other vinyl monomers containing hydroxyl groups, aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate and other vinyl monomers containing amino groups, (meth)acrylamide, N-methyl (meth)acrylamide, N-butylacrylamide and other vinyl monomers containing amide groups, (meth)acrylonitrile, cyanostyrene, cyanoacrylate and other vinyl monomers containing nitrile groups, glycidyl methacrylate, tetrahydrofurfuryl (meth)acrylate, p-vinylphenyl phenyl oxide (p-vinyl phenyl phenyl oxide) and other vinyl monomers containing epoxy groups, uretdione, isocyanurate and other vinyl monomers containing polyisocyanate groups. As monomers containing halogen elements, for example: vinyl chloride, vinyl bromide, vinylidene chloride, allyl chloride, chlorostyrene, bromostyrene, dichlorostyrene, chloromethylstyrene, tetrafluorostyrene, chloroprene, etc. can be cited.

In the case where the free radical reactivity of component (I): hardening resin is low or non-existent, from the viewpoint of reactivity, the resin composition of the present embodiment preferably contains the following component (III): hardening agent. Component (III): hardening agent generally has the function of reacting with component (I) hardening resin to harden the resin composition. The so-called "reaction" of component (I) and component (III) hardening agent means that the polar groups of each component have covalent bonding properties with each other. When polar groups react with each other, for example, the OH of a carboxyl group is detached, the original polar group changes or disappears, but the situation in which a covalent bond is formed is included in the definition of polar groups showing "reactivity" with each other.

From the viewpoint of heat resistance, the content of component (II) in the resin composition of the present embodiment is preferably 0.01 to 5 parts by mass, more preferably 0.02 to 4 parts by mass, and further preferably 0.03 to 3 parts by mass, relative to 100 parts by mass of the resin solid content of the resin composition of the present embodiment. The so-called resin solid content refers to the component obtained by removing the filler and the solvent from the resin composition.

<Component (III): Hardener (excluding component (I))> From the perspective of hardening function, it is preferred that the hardener of component (III) has at least two polar groups that can react with the functional groups of component (I): hardening resin in one molecular chain. Component (III) may be used alone or in combination of two or more. The types of polar groups possessed by component (I) and component (III) are not particularly limited, and examples thereof include: Epoxy and carboxyl, carbonyl, ester, imidazole, hydroxyl, amino, thiol, benzophenone, carbodiimide; Amino and carboxyl, carbonyl, hydroxyl, acid anhydride, sulfonic acid, aldehyde; Isocyanate and hydroxyl, carboxylic acid; Acid anhydride and hydroxyl; Silanol and hydroxyl, carboxylic acid; Halogen and carboxylic acid, carboxylate, amino, phenol, thiol; Alkoxy and hydroxyl, alkoxide, amino; Butylene diimide and cyanoacetyl, etc. The polar groups of component (I): hardening resin and component (III): curing agent can be selected arbitrarily.

Furthermore, in the case where the polar group of component (I) does not react directly with the polar group of component (III), the case where the reaction can be achieved by adding a curing accelerator such as a catalyst is also included in the definition of "reactivity". For example, in the case where component (I) is a resin having an epoxy group and component (III) is a curing agent having an acid anhydride group, the reactivity between the epoxy group and the acid anhydride group is usually very low, but by adding a compound having an amino group as a curing accelerator, the epoxy group of component (I) reacts with the amino group, and part or all of the epoxy group of component (III) becomes a hydroxyl group. The resin composition of the present embodiment is cured by reacting the above-mentioned hydroxyl group with the acid anhydride group of the curing agent of component (III).

When component (I) is a curing resin having a polar group, from the viewpoint of reactivity, the ratio of the amount of the curing agent of the above-mentioned component (I) to that of the component (III) is preferably (the mole amount of the polar group of the component (I)): (the mole amount of the polar group of the component (III)) = 1:0.01 to 1:20, more preferably 1:0.05 to 1:15, and further preferably 1:0.1 to 1:10. Specific examples of component (III): curing agent are given below. Examples of hardeners having an ester group include: EXB9451, EXB9460, EXB, 9460S, HPC8000-65T, HPC8000H-65TM, EXB8000L-65TM, EXB8150-65T, EXB9416-70BK manufactured by DIC Corporation, and YLH1026, DC808, YLH1026, YLH1030, and YLH1048 manufactured by Mitsubishi Chemical Corporation.

Examples of the hardener having a hydroxyl group include, but are not limited to, MEH-7700, MEH-7810, MEH-7851, NHN, CBN, GPH manufactured by Nippon Kayaku Co., Ltd., SN170, SN170, SN180, SN190, SN475, SN485, SN495, SN-495V, SN375 manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., TD-2090, LA-7052, LA-7054, LA-1356, LA-3018-50P, and EXB-9500 manufactured by DIC Corporation.

Examples of curing agents having a benzophenone group include ODA-BOZ manufactured by JFE Chemical, HFB2006M manufactured by Showa High Polymer Co., Ltd., and P-d and F-a manufactured by Shikoku Chemical Industries, Ltd., but are not limited thereto.

Examples of the curing agent having an isocyanate group include bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanophenylpropane), 1,1-bis(4-cyanophenylmethane), Difunctional cyanate resins such as bis(4-cyanoyl-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanophenyl-1-(methylethylidene))benzene, bis(4-cyanophenyl)sulfide, and bis(4-cyanophenyl)ether; polyfunctional cyanate resins derived from phenol novolac and cresol novolac; prepolymers obtained by partially tri-nating these cyanate resins, etc., but not limited to these. Examples of commercially available products include PT30, PT60, ULL-950S, BA230, BA230S75, etc. manufactured by Lonsa Corporation of Japan.

Examples of the hardener having a carbodiimide group include V-03 and V-07 manufactured by Nisshinbo Chemical Co., Ltd., but the hardener is not limited thereto.

Examples of the hardener having an amino group include 4,4'-methylenebis(2,6-dimethylaniline), diphenyldiaminosulfonate, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfonate, 3,3'-diaminodiphenylsulfonate, metaphenylenediamine, metaphenylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis(3-amino-4-hydroxy)benzidine, The invention also includes, but is not limited to, bis(4-(4-aminophenoxy)phenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, bis(4-(3-aminophenoxy)phenyl)sulfone, and the like. Examples of commercially available products include KAYABOND C-200S, KAYABOND C-100, Kayahard A-A, Kayahard A-B, Kayahard A-S manufactured by Nippon Kayaku Co., Ltd., and EPI-CURE W manufactured by Mitsubishi Chemical Co., Ltd. In addition, from the viewpoint of reactivity, the hardener having an amino group is preferably a primary amine and/or a secondary amine, and more preferably a primary amine.

Examples of the hardener having an acid anhydride group include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnalidic anhydride, hydrogenated methylnalidic anhydride, trialkyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, 5-(2,5-dihydrotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic dianhydride, benzophenonetetracarboxylic anhydride, and the like. The invention also includes, but is not limited to, acid anhydrides, biphenyltetracarboxylic acid anhydride, naphthalenetetracarboxylic acid anhydride, oxydiphthalic acid anhydride, 3,3',4,4'-diphenylsulfonatetetracarboxylic acid anhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxy-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, ethylene glycol bis(trimellitic anhydride ester), styrene-maleic acid resin obtained by copolymerization of styrene and maleic acid, and the like polymer-type acid anhydrides.

Furthermore, the compound having at least two of the above-mentioned structures with free radical reactivity also has the function of reacting with component (I) to cure the resin composition of the present embodiment, and can therefore be used as component (III): curing agent. As the compound having at least two structures with free radical reactivity, for example, allyl monomers such as triallyl isocyanurate (Taic manufactured by Mitsubishi Chemical Corporation), tris(2-hydroxyethyl)isocyanurate, diallyl fumarate, diallyl adipate, triallyl citrate, and diallyl hexahydrophthalate can be cited.

From the viewpoint of heat resistance, the content of component (III) in the resin composition of the present embodiment is preferably 10 to 90 parts by mass, more preferably 15 to 85 parts by mass, and further preferably 20 to 80 parts by mass, relative to 100 parts by mass of the resin solid content of the resin composition of the present embodiment. The so-called resin solid content refers to the component obtained by removing the filler and the solvent from the resin composition.

<Component (IV): Additive> The resin composition of the present embodiment may further include a curing accelerator, a filler, a flame retardant, and other additives as component (IV). In addition, the additives included as copolymers (A) and (B) also have the same meaning as component (IV) of the above-mentioned resin composition.

As a hardening accelerator, it can be added for the purpose of promoting the reactivity between the above-mentioned components, and previously known ones can be used. Examples of hardening accelerators include phosphorus-based hardening accelerators, amine-based hardening accelerators, imidazole-based hardening accelerators, guanidine-based hardening accelerators, and metal-based hardening accelerators. One hardening accelerator can be used alone, or two or more can be used in combination.

Examples of the phosphorus-based hardening accelerator include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, and the like. Preferred are triphenylphosphine and tetrabutylphosphonium decanoate, but the present invention is not limited thereto.

Examples of the amine-based curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene. Preferred are 4-dimethylaminopyridine and 1,8-diazabicyclo(5,4,0)-undecene, but the present invention is not limited thereto.

Examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl ... imidazole, 1-cyanoethyl-2-undecyl imidazole, 1-cyanoethyl-2-ethyl-4-methyl imidazole, 1-cyanoethyl-2-phenyl imidazole, 1-cyanoethyl-2-undecyl imidazole trimellitate, 1-cyanoethyl-2-phenyl imidazole trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-symmetric tris(2,4-diamino-6- [2'-Undecyl imidazolyl-(1')]-ethyl-symmetric tris(iodine), 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-symmetric tris(iodine), 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-symmetric tris(iodine) isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, Imidazole compounds such as 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, and adducts of imidazole compounds and epoxy resins, but not limited thereto, preferably 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole. As imidazole-based hardening accelerators, commercially available products may also be used, such as P200-H50 manufactured by Mitsubishi Chemical Corporation.

Examples of the guanidine-based hardening accelerator include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec- 5-ene, 1-methylbiguanidine, 1-ethylbiguanidine, 1-n-butylbiguanidine, 1-n-octadecylbiguanidine, 1,1-dimethylbiguanidine, 1,1-diethylbiguanidine, 1-cyclohexylbiguanidine, 1-allylbiguanidine, 1-phenylbiguanidine, 1-(o-tolyl)biguanidine, etc., preferably dicyanamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene, but not limited to them.

Examples of metal hardening accelerators include, but are not limited to, organic metal complexes or organic metal salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Examples of organic metal complexes include: organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, organic zinc complexes such as zinc (II) acetylacetonate, organic iron complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate. Examples of organic metal salts include zinc octylate, tin octylate, zinc cycloalkanoate, cobalt cycloalkanoate, tin stearate, zinc stearate, etc.

As fillers, for example, there can be cited: inorganic fillers such as silicon dioxide, calcium carbonate, magnesium carbonate, magnesium hydroxide, aluminum hydroxide, calcium sulfate, barium sulfate, carbon black, glass fiber, glass beads, glass balloons, glass flakes, graphite, titanium oxide, potassium titanium oxide whiskers, carbon fiber, aluminum oxide, kaolin clay, silicic acid, calcium silicate, quartz, mica, talc, clay, zirconium oxide, potassium titanium oxide, aluminum oxide, metal particles, etc.; organic fillers such as wood chips, wood powder, pulp, cellulose nanofibers, etc., but are not limited to these. These can be used alone or in combination of two or more. The shapes of the fillers may be any of scale, spherical, granular, powder, and amorphous shapes, etc., without particular limitation. From the perspective of the low dielectric constant and low dielectric dissipation factor of the resin composition and the cured product of the present embodiment, silicon dioxide is preferably used as the filler. Examples of silicon dioxide include amorphous silicon dioxide, fused silicon dioxide, crystalline silicon dioxide, synthetic silicon dioxide, and hollow silicon dioxide.

As flame retardants, for example, halogen flame retardants such as bromine compounds, phosphorus flame retardants such as aromatic compounds, metal hydroxides, alkyl sulfonates, antimony trioxide, aluminum hydroxide, magnesium hydroxide, zinc borate, flame retardants containing aromatic bromine compounds such as hexabromobenzene, decabromodiphenylethane, 4,4-dibromobiphenyl, ethylenediamine, etc., but not limited to them. These flame retardants can be used alone or in combination of two or more. Among the above flame retardants, there are also so-called flame retardant additives that have a low flame retardant performance effect by themselves, but exert a more excellent effect by using them in combination with other flame retardants.

Fillers and flame retardants may also be used that have been surface treated with a surface treatment agent such as a silane coupling agent. Surface treatment agents include, but are not limited to, fluorine-containing silane coupling agents, aminosilane-based coupling agents, epoxysilane-based coupling agents, butylsilane-based coupling agents, silane-based coupling agents, alkoxysilanes, organic silazane compounds, and titanium ester-based coupling agents. These agents may be used alone or in combination of two or more.

As other additives, there are no particular restrictions as long as they are commonly used in the formulation of resin compositions and/or cured products. Examples of such other additives include: pigments and/or colorants such as carbon black and titanium oxide; lubricants such as stearic acid, behenic acid, zinc stearate, calcium stearate, magnesium stearate, and ethyl distearate; mold release agents; organic polysiloxanes, phthalate-based or fatty acid esters such as adipic acid ester compounds and azelaic acid ester compounds; , mineral oil and other plasticizers; hindered phenolic, phosphorus-based heat stabilizers and other antioxidants; hindered amine-based light stabilizers; benzotriazole-based ultraviolet absorbers; antistatic agents; organic fillers; thickeners; defoamers; leveling agents; resin additives such as adhesion agents; other additives or mixtures thereof, but not limited to them.

From the perspective of low dielectric constant and low dielectric dissipation factor of the resin composition and cured product of the present embodiment, it is preferred that the resin composition and cured product do not contain pigments, colorants, lubricants, release agents, or antistatic agents.

The resin composition of the present embodiment may be obtained by melt-kneading the components, or by dissolving the components in a solvent capable of dissolving the components and stirring the mixture (hereinafter referred to as "varnish"). From the viewpoint of operability, varnish is preferred. As the solvent, for example, ketones such as acetone, methyl ethyl ketone (MEK) and cyclohexanone; acetates such as ethyl acetate, butyl acetate, solvent acetate, propylene glycol monomethyl ether acetate and carbitol acetate; carbitols such as solvent and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone, etc., but are not limited to these. Organic solvents can be used alone or in combination of two or more.

[Cured product] The cured product of the present embodiment is a cured product of the resin composition of the present embodiment, and can be obtained by subjecting the resin composition of the present embodiment to a curing reaction at an arbitrary temperature and time. The so-called cured product of the present embodiment refers to a concept that includes not only a completely cured product but also a state in which only a part of the resin composition is cured and an uncured component is included (semi-cured). In the manufacturing process of the laminate described below, a step of further curing the cured product can also be implemented. The reaction temperature of the curing step of the cured product of the present embodiment is preferably 80°C or more, more preferably 100°C or more, and further preferably 120°C or more. The reaction time is preferably 10 to 240 minutes, more preferably 20 to 230 minutes, and further preferably 30 to 220 minutes. When the resin composition of the present embodiment is a varnish, it is preferred to perform the curing reaction after removing the solvent. As a drying method, it can be implemented by previously known methods such as heating and hot air blowing, preferably at a temperature lower than the curing reaction temperature. Regarding the amount of solvent in the resin composition, drying is performed in a manner that is preferably 10% by mass or less, and more preferably 5% by mass or less.

[Resin film] The resin film of the present embodiment includes the resin composition of the present embodiment. Furthermore, the resin film of the present embodiment includes the cured product of the present embodiment. The resin film of the present embodiment can be obtained by spreading a varnish including the resin composition of the present embodiment in a uniform film on an appropriate support, performing a drying treatment as described above, and removing the solvent. The resin film can be rolled up and stored. The resin film of the present embodiment can also be configured to have a predetermined protective film laminated thereon, and in this case, it can be used by peeling off the protective film. Examples of the support include: a film including a plastic material, a metal foil, a release paper, and the like. Examples of the film containing a plastic material as a support include polyesters such as polyethylene terephthalate and polyethylene naphthalate, polycarbonate, acrylic resins such as polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. From the perspective of availability and cost, polyethylene terephthalate and polyethylene naphthalate are preferred. As metal foils, examples include copper foils and aluminum foils, and copper foils are preferred. As the copper foil, a foil of a single metal containing copper can be used, or a foil of an alloy containing copper and other metals (such as tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.) can be used. In addition, the surface of the support body bonded to the resin composition layer can also be subjected to matte treatment, corona treatment, antistatic treatment, and mold release treatment.

[Prepreg] The prepreg of the present embodiment includes a substrate, and the resin composition of the present embodiment or its cured product impregnated in or coated on the substrate. That is, the prepreg of the present embodiment is a composite of the resin composition or cured product of the present embodiment and the substrate. The prepreg can be obtained by, for example, impregnating a substrate such as glass cloth with a varnish of the resin composition of the present embodiment and then removing the solvent by the above-mentioned drying method. As the substrate, for example, various glass cloths such as yarn cloth, cloth, chopped strands of felt, and surface felt can be cited; asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloths; woven or non-woven fabrics obtained from liquid crystal fibers such as wholly aromatic polyamide fibers, wholly aromatic polyester fibers, and polybenzoxazole fibers; natural fiber cloths such as cotton cloth, linen cloth, and felt; natural fiber-based substrates such as carbon fiber cloth, kraft paper, cotton paper, and cloth obtained from paper-glass mixed yarn; polytetrafluoroethylene porous membranes, etc. From the perspective of dielectric properties, glass cloth is preferred. These substrates can be used alone or in combination of two or more. The ratio of the solid content of the resin composition of the present embodiment in the prepreg is preferably 30 to 80% by mass, and more preferably 40 to 70% by mass. When the above ratio is 30% by mass or more, when the prepreg is used for electronic substrates, etc., there is a tendency for the insulation reliability to be more excellent. When the above ratio is 80% by mass or less, there is a tendency for the mechanical properties such as rigidity to be more excellent in the use of electronic substrates, etc.

[Laminate] The laminate of the present embodiment has the resin film and metal foil described above. Furthermore, the laminate of the present embodiment has the cured product of the prepreg described above and metal foil. The laminate of the present embodiment can be manufactured, for example, by the following steps: step (a), laminating a resin film containing the resin composition of the present embodiment on a substrate to form a resin layer to obtain a prepreg; step (b), heating and pressurizing the resin layer to flatten it to obtain a cured product of the prepreg; step (c), further forming a prescribed wiring layer containing a metal foil on the resin layer. In the above step (a), the method of laminating the resin film on the substrate is not particularly limited. For example, there can be cited a method of laminating using a multi-stage press, a vacuum press, a normal pressure laminating machine, and a laminating machine that heats and presses under vacuum, etc. Preferably, the method using a laminating machine that heats and presses under vacuum is used. According to the method using the laminating machine, even if the target electronic circuit substrate has fine wiring circuits on the surface, the resin can be embedded between the circuits without pores. In addition, the lamination can be a batch type or a continuous type using a roller or the like. Furthermore, the prepreg constituting the laminate of the present embodiment can also be in the form of a cured product having a substrate and a resin composition.

As the substrate of the above-mentioned laminate, in addition to the substrate constituting the prepreg, for example, glass epoxy substrate, metal substrate, polyester substrate, polyimide substrate, polyphenylene ether substrate, fluororesin substrate, etc. The surface of the substrate for the laminate resin layer may also be roughened in advance, and the number of substrate layers is not limited.

In the above step (b), the resin film and substrate layered in the above step (a) are heated and pressed to be flattened. The conditions can be arbitrarily adjusted according to the type of substrate or the composition of the resin film, for example, preferably the temperature is 100-300°C, the pressure is 0.2-20 MPa, and the time is 30-180 minutes. In the above step (c), a prescribed wiring layer including a metal foil is further formed on the resin layer produced by heating and pressing the resin film and the substrate. The formation method is not particularly limited, and previously known methods can be cited, such as etching methods such as subtractive methods, semi-additive methods, etc. The subtractive method is a method in which an anti-etching coating corresponding to the desired pattern shape is formed on the metal layer, and the metal layer where the anti-etching agent is removed is dissolved and removed with a chemical solution in a subsequent development process, thereby forming the desired wiring. The semi-additive method is a method in which a metal film is formed on the surface of the resin layer by electroless plating, and an anti-plating coating corresponding to the desired pattern shape is formed on the metal film, and then a metal layer is formed by electrolytic plating, and then the unnecessary electroless plating layer is removed with a chemical solution, etc., to form the desired wiring layer.

In addition, holes such as vias may be formed in the resin layer as needed. The method for forming the holes is not particularly limited, and a previously known method may be used. For example, NC drilling, carbon dioxide laser, UV laser, YAG laser, plasma, etc. may be used as the method for forming the holes.

[Metal foil laminate] The laminate of the present embodiment described above may be in the form of a plate or a flexible laminate having flexibility. The laminate of the present embodiment may also be a metal foil laminate. The metal foil laminate may be obtained by curing the resin composition of the present embodiment or the prepreg of the present embodiment and a metal foil laminate, and is configured to have a structure in which a portion of the metal foil is removed from the metal foil laminate. The metal foil laminate is preferably in a form in which a cured product of the prepreg (also referred to as a "cured product composite") and a metal foil laminate are closely connected, and can be preferably used as a material for electronic circuit substrates.

As metal foil, for example, aluminum foil and copper foil can be cited, and among them, copper foil is preferred because of its low electrical resistance. The cured product of the prepreg combined with the metal foil may be one sheet or multiple sheets, and the metal foil is stacked on one side or both sides of the cured product composite to form a laminate according to the application. As a method for manufacturing the above-mentioned laminate, for example, the following method can be cited: a prepreg composed of the resin composition of the present embodiment and a substrate is formed, and after stacking it with a metal foil, the resin composition is cured to obtain a laminated board on which the cured product of the prepreg and the metal foil are stacked. One of the particularly preferred uses of the above-mentioned laminated board is a printed wiring board. The printed wiring board is preferably a metal foil laminate with at least a portion of the metal foil removed. The printed wiring board of this embodiment can be produced by a method of pressurizing and heating the prepreg of this embodiment. As a substrate, the same as that described above with respect to the prepreg can be used. The above-mentioned printed wiring board has excellent strength and electrical properties (low dielectric constant and low dielectric dissipation factor) by including the resin composition of this embodiment, and can suppress the change of electrical properties accompanying environmental changes, and has excellent insulation reliability and mechanical properties.

[Printed wiring board] The printed wiring board of the present embodiment includes a cured product of the resin composition of the present embodiment. The printed wiring board of the present embodiment can be produced using the resin composition and/or varnish of the present embodiment described above. The printed wiring board of the present embodiment includes at least one selected from the group consisting of a cured product of the above-mentioned resin composition, a resin film containing the resin composition of the present embodiment or its cured product, and a prepreg as a composite of a substrate and a resin composition or a cured product. The printed wiring board of the present embodiment can be used as a metal foil with a resin. [Example]

The present embodiment is described in detail below by taking specific embodiments and comparative examples as examples, but the present invention is not limited to the following embodiments in any way. First, the evaluation method and the method for measuring physical properties applied to the embodiments and comparative examples are described below.

[Specification of the structure of copolymer (A) and copolymer (B), and determination of physical properties] ((1) Content of vinyl aromatic monomer unit (styrene) in copolymer) The copolymer before hydrogenation was measured by proton nuclear magnetic resonance ( ¹ H-NMR) method. The measurement was carried out under the following conditions: the measurement instrument was JNM-LA400 (manufactured by JEOL), the solvent was deuterated chloroform, the sample concentration was 50 mg/mL, the observation frequency was 400 MHz, the chemical shift reference was tetramethylsilane, the pulse delay was 2.904 seconds, the number of scans was 64, the pulse width was 45°, and the measurement temperature was 26°C. The styrene content was calculated using the cumulative value of the total styrene aromatic signal at 6.2 to 7.5 ppm in the spectrum.

((2) Vinyl bond content of copolymer) The vinyl bond content of the copolymer before hydrogenation was measured by proton nuclear magnetic resonance ( ¹ H-NMR) method. The measurement conditions and the method of processing the measurement data were the same as those in (1) above. The vinyl bond content was obtained by calculating the integral value per 1H of each bonding mode from the integral values of the signals attributable to 1,4-bonding and 1,2-bonding, and dividing the integral value of 1,2-bonding by the total value of the integral values of 1,4-bonding and 1,2-bonding (1,2-bonding is in the case of butadiene, and becomes 3,4-bonding in the case of isoprene).

((3) Mass ratio of vinyl aromatic monomer units in random polymer blocks (RS) and content of polymer blocks mainly composed of vinyl aromatic monomer units (BS)) The following definitions are made. BSa: content of polymer blocks mainly composed of vinyl aromatic monomer units in copolymer (A) BSb: content of polymer blocks mainly composed of vinyl aromatic monomer units in copolymer (B) RSa: mass ratio of vinyl aromatic monomer units in random polymer blocks of copolymer (A) RSb: mass ratio of vinyl aromatic monomer units in random polymer blocks of copolymer (B) Copolymer (A) and copolymer (B) were used as test samples, and the vinyl aromatic monomer units contained in ^each were distinguished into those derived from "polymer blocks mainly composed of vinyl aromatic monomer units" and those derived from "random polymer blocks containing vinyl aromatic monomer units and covalent diene monomer units" by proton nuclear magnetic resonance method ( 1 H-NMR, ECS400 manufactured by JOEL RESONABCE). The following conditions were used: deuterated chloroform was used as solvent, the sample concentration was 50 mg/mL, the observation frequency was 400 MHz, tetramethylsilane was used as chemical shift standard, the pulse delay was 2.904 seconds, the number of scans was 256, and the measurement temperature was 23°C. Based on the integrated intensity of the signal attributed to the aromatic group, the amount of random and block aromatic monomer units was calculated from the integrated value per 1H of each bonding mode, and the total styrene content was calculated, and the styrene mass ratio in the random polymer block (hereinafter, recorded as the random styrene amount) (RSa) (RSb) and the styrene block content in the copolymer (BSa) (BSb) were calculated. The calculation method is as follows. Styrene block strength (b-St strength) = (cumulative value of 6.9 ppm to 6.3 ppm)/2 Random styrene strength (r-St strength) = (cumulative value of 7.5 ppm to 6.9 ppm) - 3×(b-St) Ethylene-butene strength (EB strength) = total cumulative value - 3×{(b-St strength) + (r-St strength)}/8 Styrene block content (BS) = 104×(b-St strength) /[104×{(b-St strength) + (r-St strength)} + 56×(EB strength)] Random styrene content (RS) = 104×(r-St strength)/{104×(r-St strength) + 56×(EB strength)}

((4) Number average molecular weight (Mn)) The number average molecular weights of copolymer (A) and copolymer (B) were measured using GPC [device: Tosoh HLC8220, column TSKgel SuperH-RC × 2]. Tetrahydrofuran was used as the solvent. The measurement was carried out at a temperature of 35°C. The number average molecular weight converted to polystyrene was obtained using a calibration curve prepared using commercially available standard polystyrene with a known weight average molecular weight. In the table, the number average molecular weight of copolymer (A) is referred to as (Mna), and the number average molecular weight of copolymer (B) is referred to as (Mnb).

(Mass ratio of copolymer (A) and copolymer (B) in (5)) The mass ratio of copolymer (A) and copolymer (B) was measured using a mixture of copolymer (A) and copolymer (B) using GPC [device: Tosoh HLC8220, column TSKgel SuperH-RC × 2]. Tetrahydrofuran was used as the solvent. Regarding the measurement conditions, the temperature was 35°C. The mass ratio of copolymer (A) and copolymer (B) was calculated from the area ratio of the peaks from copolymer (A) and copolymer (B).

((6) Hydrogenation rate) The hydrogenation rates of the copolymers (A) and (B) were measured using a nuclear magnetic resonance apparatus (DPX-400, manufactured by BRUKER). The copolymers after hydrogenation, i.e., hydrogenated copolymers, were measured using proton nuclear magnetic resonance ( ¹ H-NMR). Specifically, the integral value of the signal from the residual double bond at 4.5 to 5.5 ppm and the signal from the hydrogenated covalent diene was calculated, and their ratio was calculated.

((7) Calculation of average hydrogenation rate H (%) and average vinyl bond content (V)) The average hydrogenation rate (H) and average vinyl bond content (V) are calculated by the following formula. Average hydrogenation rate (H) = (hydrogenation rate of copolymer (A)) × (mass ratio of copolymer (A)) + (hydrogenation rate of copolymer (B)) × (mass ratio of copolymer (B)) Average vinyl bond content (V) = (vinyl bond content of copolymer (A)) × (mass ratio of copolymer (A)) + (vinyl bond content of copolymer (B)) × (mass ratio of copolymer (B))

(Fraction of copolymer (A) and copolymer (B) as components of the following copolymer (X)) Using GPC [apparatus: Waters ACQUITY UPLC H-Class, columns: Waters ACQUITY APC XT900 (2.5 μm, 4.6×150 mm), Waters ACQUITY APC XT200 (2.5 μm, 4.6×75 mm), Waters ACQUITY APC XT125 (2.5 mm, 4.6×75 mm) in series], copolymer (X) was fractionated into copolymer (A) as a low molecular weight component and copolymer (B) as a high molecular weight component. Chloroform was used as a solvent. Based on the GPC measurement chart, the components were fractionated into the low molecular weight peak and the high molecular weight peak.

[Materials for copolymers and resin compositions] (Preparation of hydrogenated catalyst) In the following examples and comparative examples, the hydrogenated catalyst used in the preparation of copolymers was prepared by the following method. A reaction vessel equipped with a stirring device was replaced with nitrogen in advance, and 1 liter of dried and purified cyclohexane was added thereto. Then, 100 mmol of bis(η5-cyclopentadienyl)titanium dichloride was added. While the mixture was stirred thoroughly, a n-hexane solution containing 200 mmol of trimethylaluminum was added, and the mixture was reacted at room temperature for about 3 days. In this way, a hydrogenated catalyst was obtained.

(Copolymer (A) and Copolymer (B)) Copolymers (A1) to (A18), copolymers (B1) to (B22), and copolymer (X1) were produced as follows.

<Production Example 1: Copolymer (A1)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.301 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 36% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A1).

<Production Example 2: Copolymer (A2)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.337 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene was added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 20% by mass, the random styrene content (RSa) is 0% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A2).

<Production Example 3: Copolymer (A3)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 15 parts by mass of styrene was added. Next, 1.28 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 85 parts by mass of butadiene was added, and polymerization was carried out for 30 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 75% by mass, the styrene content (Sa) is 15% by mass, the random styrene content (RSa) is 0% by mass, the styrene block content (BSa) is 15% by mass, the styrene block molecular weight (MnSa) is 1200, and the number average molecular weight (Mna) is 8,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A3).

<Production Example 4: Copolymer (A4)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.320 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.6 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 72 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60 mass%, the styrene content (Sa) is 28 mass%, the random styrene content (RSa) is 10 mass%, the styrene block content (BSa) is 20 mass%, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 mass parts of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A4).

<Production Example 5: Copolymer (A5)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 1.16 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 72 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 36% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 1600, and the number average molecular weight (Mna) is 8,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A5).

<Production Example 6: Copolymer (A6)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.267 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 36% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 7000, and the number average molecular weight (Mna) is 35,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A6).

<Production Example 7: Copolymer (A7)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 25 parts by mass of styrene was added. Next, 0.320 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 7 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 68 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60 mass%, the styrene content (Sa) is 32 mass%, the random styrene content (RSa) is 20 mass%, the styrene block content (BSa) is 25 mass%, the styrene block molecular weight (MnSa) is 7500, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 mass parts of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A7).

<Production Example 8: Copolymer (A8)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.305 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 30% by mass, the styrene content (Sa) is 36% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A8).

<Production Example 9: Copolymer (A9)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.305 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.6 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 36% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C, and the hydrogenation reaction is stopped halfway. The hydrogenation rate of the obtained hydrogenated copolymer is 70%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A9).

<Production Example 10: Copolymer (A10)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.305 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.6 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60 mass%, the styrene content (Sa) is 36 mass%, the random styrene content (RSa) is 20 mass%, the styrene block content (BSa) is 20 mass%, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Then, 0.3 mass parts of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate is added as a stabilizer relative to 100 mass parts of the hydrogenated copolymer to obtain a copolymer (A10).

<Production Example 11: Copolymer (A11)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.183 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.8 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 61 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 36% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 10,000, and the number average molecular weight (Mna) is 50,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A11).

<Production Example 12: Copolymer (A12)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.279 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.8 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 30 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 50 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 40% by mass, the styrene content (Sa) is 50% by mass, the random styrene content (RSa) is 37.5% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A12).

<Production Example 13: Copolymer (A13)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 30 parts by mass of styrene was added. Next, 0.305 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.6 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 7 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 63 parts by mass of butadiene were added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60 mass%, the styrene content (Sa) is 37 mass%, the random styrene content (RSa) is 10 mass%, the styrene block content (BSa) is 30 mass%, the styrene block molecular weight (MnSa) is 9000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 mass parts of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A13).

<Production Example 14: Copolymer (A14)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene were added. Next, 0.337 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.6 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 50 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bonding amount (Va) is 60% by mass, the styrene content (Sa) is 20% by mass, the random styrene content (RSa) is 20% by mass, the styrene block content (BSa) is 0% by mass, the styrene block molecular weight (MnSa) is 0, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A14).

<Production Example 15: Copolymer (B1)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer based on 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B1).

<Production Example 16: Copolymer (B2)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution containing 10 parts by mass of styrene (concentration 20% by mass) was added and polymerized for 20 minutes. Then, a cyclohexane solution containing 10 parts by mass of butadiene (concentration 20% by mass) was added and polymerized for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60% by mass, the styrene content (Sb) was 34% by mass, the random styrene content (RSb) was 17.5% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 15,000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B2).

<Production Example 17: Copolymer (B3)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of styrene was added. Next, 0.116 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.0 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 75 parts by mass of butadiene was added, and polymerization was carried out for 60 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 7 parts by mass of styrene was added, and polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20% by mass) containing 10 parts by mass of butadiene was added and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 75% by mass, the styrene content (Sb) was 15% by mass, the random styrene content (RSb) was 0% by mass, the styrene block content (BSb) was 15% by mass, the styrene block molecular weight (MnSb) was 6750, and the number average molecular weight (Mnb) was 90,000. Furthermore, a hydrogenation catalyst prepared in the above manner was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Next, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B3).

<Production Example 18: Copolymer (B4)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.064 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 7 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 63 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 1 part by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 9 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 28 mass%, the random styrene content (RSb) was 50 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B4).

<Production Example 19: Copolymer (B5)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.031 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.1 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 7 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 63 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 1 part by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 9 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 30,000, and the number average molecular weight (Mnb) was 300,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B5).

<Production Example 20: Copolymer (B6)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 5 parts by mass of styrene was added. Next, 0.044 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 72 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 5 parts by mass of styrene was added, and the polymerization was carried out for 10 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 1 part by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 9 parts by mass of butadiene were added, and the polymerization was carried out for 10 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 19 mass%, the random styrene content (RSb) was 10 mass%, the styrene block content (BSb) was 10 mass%, the styrene block molecular weight (MnSb) was 22000, and the number average molecular weight (Mnb) was 220,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B6).

<Production Example 21: Copolymer (B7)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.064 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 30 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B7).

<Production Example 22: Copolymer (B8)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 10 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 15000. Furthermore, a hydrogenation catalyst prepared in the above manner was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Next, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B8).

<Production Example 23: Copolymer (B9)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C, and the hydrogenation reaction was stopped halfway. The hydrogenation rate of the obtained hydrogenated copolymer was 70%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B9).

<Production Example 24: Copolymer (B10)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 150,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (B10).

<Production Example 25: Copolymer (B11)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.092 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 10 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 10000, and the number average molecular weight (Mnb) was 100,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer based on 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B11).

<Production Example 26: Copolymer (B12)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.085 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20% by mass) containing 10 parts by mass of styrene was added and the polymerization was carried out for 10 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60% by mass, the styrene content (Sb) was 36% by mass, the random styrene content (RSb) was 20% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 11,000, and the number average molecular weight (Mnb) was 110,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B12).

<Production Example 27: Copolymer (B13)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.056 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 26 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 44 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 4 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 6 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 40 mass%, the styrene content (Sb) was 50 mass%, the random styrene content (RSb) was 40 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 15000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B13).

<Production Example 28: Copolymer (B14)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene were added. Next, 0.067 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 60 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) is 60 mass%, the styrene content (Sb) is 20 mass%, the random styrene content (RSb) is 20 mass%, the styrene block content (BSb) is 0 mass%, the styrene block molecular weight (MnSb) is 0, and the number average molecular weight (Mnb) is 150,000. Furthermore, a hydrogenation catalyst prepared in the above manner is added to the obtained copolymer at 100 ppm based on Ti per 100 mass parts of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer is 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (B14).

<Production Example 29: Copolymer (B15)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.123 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 7000, and the number average molecular weight (Mnb) was 70,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer per 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B15).

<Production Example 30: Copolymer (B16)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.085 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 10 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 11000, and the number average molecular weight (Mnb) was 110,000. Furthermore, a hydrogenation catalyst prepared in the above manner was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Next, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B16).

<Production Example 31: Copolymer (B17)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.085 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added, and the polymerization was carried out for 10 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 2 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of butadiene were added, and the polymerization was carried out for 10 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60 mass%, the styrene content (Sb) was 36 mass%, the random styrene content (RSb) was 20 mass%, the styrene block content (BSb) was 20 mass%, the styrene block molecular weight (MnSb) was 11000, and the number average molecular weight (Mnb) was 110,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (B17).

<Production Example 32: Copolymer (B18)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 10 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 16 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 64 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20% by mass) containing 10 parts by mass of styrene was added and the polymerization was carried out for 10 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60% by mass, the styrene content (Sb) was 36% by mass, the random styrene content (RSb) was 20% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 15,000, and the number average molecular weight (Mnb) was 150,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B18).

<Production Example 33: Copolymer (X1)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 7.4 mass parts of styrene was added. Next, 0.05 mass parts of n-butyl lithium relative to 100 mass parts of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 9.9 mass parts of styrene and a cyclohexane solution (concentration 20 mass%) containing 39.7 mass parts of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 5.0 mass parts of styrene was added, and polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 7.6 mass parts of styrene and 0.165 mass parts of n-butyl lithium relative to 100 mass parts of all monomers, and 0.6 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20 mass%) containing 6.1 mass parts of styrene and a cyclohexane solution (concentration 20 mass%) containing 24.3 mass parts of butadiene were added, and polymerization was carried out for 20 minutes. Then, methanol was added to stop the polymerization reaction. The polymer obtained in the above manner was separated into a low molecular weight component (copolymer (A)) and a high molecular weight component (copolymer (B)) by chromatography and analyzed separately. The results showed that in copolymer (A), the vinyl bonding amount (Va) was 60% by mass, the styrene content (Sa) was 36% by mass, the random styrene content (RSa) was 20% by mass, the styrene block content (BSa) was 20% by mass, the styrene block molecular weight (MnSa) was 3600, and the number average molecular weight (Mna) was 18,000. In copolymer (B), the vinyl bonding amount (Vb) was 60% by mass, the styrene content (Sb) was 36% by mass, the random styrene content (RSb) was 20% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 15,000, and the number average molecular weight (Mnb) was 150,000. In addition, the content ratio of copolymer (A) to copolymer (B) is (A)/(B)=30/70. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C. The hydrogenation rate of the obtained hydrogenated copolymer was 98%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (X1) which is a mixture of copolymer (A) and copolymer (B).

<Production 34: Copolymer (A15)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.337 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene was added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 20% by mass, the random styrene content (RSa) is 0% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate is added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (A15).

<Production Example 35: Copolymer (A16)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.337 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene was added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained as above, the vinyl bond content (Va) is 60% by mass, the styrene content (Sa) is 20% by mass, the random styrene content (RSa) is 0% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Furthermore, a hydrogenation catalyst prepared as above is added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction is carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C, and the hydrogenation reaction is stopped halfway. The hydrogenation rate of the obtained hydrogenated copolymer is 30%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (A16).

<Production Example 36: Copolymer (A17)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 1.02 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.7 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene was added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 60 mass%, the styrene content (Sa) is 20 mass%, the random styrene content (RSa) is 0 mass%, the styrene block content (BSa) is 20 mass%, the styrene block molecular weight (MnSa) is 2000, and the number average molecular weight (Mna) is 10,000. Then, 0.3 mass parts of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate is added as a stabilizer relative to 100 mass parts of the hydrogenated copolymer to obtain a copolymer (A17).

<Production Example 37: Copolymer (A18)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 20 parts by mass of styrene was added. Next, 0.337 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.2 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 15 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 80 parts by mass of butadiene was added, and polymerization was carried out for 45 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Va) is 30% by mass, the styrene content (Sa) is 20% by mass, the random styrene content (RSa) is 0% by mass, the styrene block content (BSa) is 20% by mass, the styrene block molecular weight (MnSa) is 6000, and the number average molecular weight (Mna) is 30,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate is added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (A18).

<Production Example 38: Copolymer (B19)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution containing 10 parts by mass of styrene (concentration 20% by mass) was added and polymerized for 20 minutes. Then, a cyclohexane solution containing 10 parts by mass of butadiene (concentration 20% by mass) was added and polymerized for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60% by mass, the styrene content (Sb) was 34% by mass, the random styrene content (RSb) was 17.5% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 15,000, and the number average molecular weight (Mnb) was 150,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (B19).

<Production Example 39: Copolymer (B20)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 1.3 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution containing 10 parts by mass of styrene (concentration 20% by mass) was added and polymerized for 20 minutes. Then, a cyclohexane solution containing 10 parts by mass of butadiene (concentration 20% by mass) was added and polymerized for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60% by mass, the styrene content (Sb) was 34% by mass, the random styrene content (RSb) was 17.5% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 15,000, and the number average molecular weight (Mnb) was 150,000. Furthermore, a hydrogenation catalyst prepared as above was added to the obtained copolymer at 100 ppm based on Ti per 100 parts by mass of the copolymer, and a hydrogenation reaction was carried out under the conditions of a hydrogen pressure of 0.7 MPa and a temperature of 80°C, and the hydrogenation reaction was stopped halfway. The hydrogenation rate of the obtained hydrogenated copolymer was 30%. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B20).

<Production Example 40: Copolymer (B21)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 10 parts by mass of styrene was added. Next, 0.061 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.4 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 14 parts by mass of styrene and a cyclohexane solution (concentration 20 mass%) containing 56 parts by mass of butadiene were added, and polymerization was carried out for 60 minutes. Then, a cyclohexane solution containing 10 parts by mass of styrene (concentration 20% by mass) was added, and the polymerization was carried out for 20 minutes. Then, a cyclohexane solution containing 10 parts by mass of butadiene (concentration 20% by mass) was added, and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 30% by mass, the styrene content (Sb) was 34% by mass, the random styrene content (RSb) was 17.5% by mass, the styrene block content (BSb) was 20% by mass, the styrene block molecular weight (MnSb) was 15,000, and the number average molecular weight (Mnb) was 150,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain copolymer (B21).

<Production Example 41: Copolymer (B22)> Batch polymerization was carried out using a tank reactor (content volume 10 L) equipped with a stirring device and a jacket. A cyclohexane solution (concentration 20 mass%) containing 8 parts by mass of styrene was added. Next, 0.116 parts by mass of n-butyl lithium relative to 100 parts by mass of all monomers and 0.8 mol of N,N,N',N'-tetramethylethylenediamine relative to 1 mol of n-butyl lithium were added, and polymerization was carried out at 70°C for 20 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 75 parts by mass of butadiene was added, and polymerization was carried out for 60 minutes. Next, a cyclohexane solution (concentration 20 mass%) containing 7 parts by mass of styrene was added, and polymerization was carried out for 20 minutes. Then, a cyclohexane solution (concentration 20% by mass) containing 10 parts by mass of butadiene was added and the polymerization was carried out for 20 minutes. Thereafter, methanol was added to stop the polymerization reaction. In the polymer obtained in the above manner, the vinyl bond content (Vb) was 60% by mass, the styrene content (Sb) was 15% by mass, the random styrene content (RSb) was 0% by mass, the styrene block content (BSb) was 15% by mass, the styrene block molecular weight (MnSb) was 6750, and the number average molecular weight (Mnb) was 90,000. Then, 0.3 parts by mass of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate was added as a stabilizer relative to 100 parts by mass of the hydrogenated copolymer to obtain a copolymer (B22).

<Production Example 42: Polyphenylene ether (PPE)> As a polar resin, a polyphenylene ether resin (PPE) was polymerized in the following manner. 0.2512 g of cupric chloride dihydrate, 1.1062 g of 35% hydrochloric acid, 3.6179 g of di-n-butylamine, 9.5937 g of N,N,N',N'-tetramethylpropylenediamine, 211.63 g of methanol and 493.80 g of n-butanol, and 180.0 g of 2,6-dimethylphenol containing 5 mol% of 2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane were added to a 1.5-liter jacketed reactor equipped with an aerator for introducing oxygen-containing gas at the bottom of the reactor, a stirring turbine blade and a baffle, and a reflux condenser at the vent gas line at the top of the reactor. The mass ratio of the solvent used was n-butanol:methanol = 70:30. Then, while stirring vigorously, oxygen was introduced into the reactor from the sprayer at a rate of 180 ml/min, and the heat medium was used to adjust the polymerization temperature through the jacket to maintain it at 40°C. The polymerization solution gradually took on the state of slurry. When the polyphenylene ether reached the required number average molecular weight, the introduction of oxygen-containing gas was stopped, and the obtained polymerization mixture was heated to 50°C. Then, hydroquinone (a reagent manufactured by Wako Pure Chemical Industries, Ltd.) was added little by little, and the temperature was kept at 50°C until the slurry-like polyphenylene ether turned white. Then, 720 g of a methanol solution containing 6.5 mass% of 36% hydrochloric acid was added, filtered, and then repeatedly washed with methanol to obtain wet polyphenylene ether. Then, vacuum drying was performed at 100°C to obtain dry polyphenylene ether. ηsp/c was 0.103 dl/g, and the yield was 97%. ηsp/c was determined by preparing the above polyphenylene ether into a 0.5 g/dl chloroform solution, and using an Oobleck viscometer to determine the reduced viscosity (ηsp/c) at 30°C. The unit is dl/g. The obtained polyphenylene ether was modified as follows. 152.5 g of polyphenylene ether and 152.5 g of toluene were mixed and heated to about 85°C. Then, 2.1 g of dimethylaminopyridine was added. When all the solids were dissolved, 18.28 g of methacrylic anhydride was slowly added. The obtained solution was kept at 85°C for 3 hours while being continuously mixed. Then, the solution was cooled to room temperature to obtain a toluene solution of methacrylate-terminated polyphenylene ether. 1000 mL of 10°C methanol was added dropwise to the obtained toluene solution into a cylindrical 3 L SUS container equipped with a homogenizer for stirring. The obtained powder was filtered, washed with methanol, and dried at 85°C under nitrogen for 18 hours.

[Examples and Comparative Examples of Using PPE as Curing Resin] (Examples 1 to 25, Examples 30 to 34), (Comparative Examples 1 to 8) The following components were used to prepare a resin composition according to the following preparation method.

<Copolymer (A)> Copolymers (A1) to (A14) prepared in Production Examples (1) to (14) Copolymers (A15) to (A18) prepared in Production Examples (34) to (37) Styrene butadiene copolymer ("Ricon 100 (product name)", manufactured by Cray Valley Co., Ltd., styrene: 25% by mass, butadiene: 75% by mass, 1,2-vinyl group in butadiene: 70%, number average molecular weight 4500, block styrene content: 0% by mass, hydrogenation rate: 0%) <Copolymer (B)> Copolymers (B1) to (B18) prepared in Production Examples (15) to (32) Copolymers (B19) to (B22) prepared in Production Examples (38) to (41) <Mixture of copolymer (A) and copolymer (B)> Copolymer (X1) prepared in Production Example (33) <Component (I): Hardened resin> PPE prepared in Production Example 42 <Component (II): Free radical initiator> Perbutyl P (manufactured by NOF Corporation) <Component (III): Hardener> Triallyl isocyanurate (TAIC ^TM ) (manufactured by Mitsubishi Chemical Corporation)

(Preparation of resin composition and varnish) Using the copolymers (A), (B), and (X) of the production examples (1) to (41), and using the above-mentioned components (I), (II), and (III), each component was weighed according to the composition shown in the following table and placed in a container, and dissolved and stirred with toluene (manufactured by Wako Junyaku Co., Ltd.) to prepare a varnish containing the resin composition. When preparing the film, the viscosity was adjusted by the amount of toluene added. At this time, the concentration of the resin composition in the varnish was adjusted to 40 to 60% by mass.

(Prepreg using varnish and preparation of cured prepreg) After impregnating a glass substrate (L2116, #2116 type, "L glass", manufactured by Asahi Kasei Corporation) with a varnish of a resin composition as shown in the following table, the prepreg was dried by heating at 130°C for 50 minutes to obtain a prepreg. The obtained prepreg was stacked in 6 pieces for lamination, and the temperature was raised to 200°C at a heating rate of 5°C/min, and heated and pressed at 200°C for 2 hours and a pressure of 3 MPa to obtain a cured prepreg with a thickness of 0.7 mm.

(Evaluation criteria for Examples 1 to 25, 30 to 34, and Comparative Examples 1 to 8) <(1) Varnish solubility> The resin composition prepared according to the composition shown in the following table was added to toluene in such a manner that the solid content concentration was 40 mass % and 60 mass %, respectively, and stirred at 40°C for 120 minutes. The solutions were used as evaluation samples and evaluated in the following three stages. [Evaluation criteria] ○: No dissolved residue was found in the solutions with a solid content concentration of 40 mass % and 60 mass %. Δ: No dissolved residue was found in the solution with a solid content concentration of 40 mass %. ×: Dissolved residue was found in all solutions.

<(2) Storage stability of varnish> The varnishes of the above-mentioned examples and comparative examples were observed when left at 30°C/50%RH, and the number of days until layer separation and/or precipitation of gel components occurred and the presence or absence thereof were evaluated according to the following criteria. The "-" in the table means that the varnish produced dissolved residues during preparation and could not be evaluated. [Evaluation criteria] ◎: 720 hours or more (including no precipitation) ○: 360 to less than 720 hours Δ: 24 to 360 hours ×: less than 24 hours

<(3) Dielectric properties> The dielectric dissipation factor of the obtained prepreg at 10 GHz was measured by the cavity resonance method. A network analyzer (N5230A, manufactured by Agilent Technologies) and a cavity resonator (Cavity Resornator CP series) manufactured by Kanto Electronics Application Development Co., Ltd. were used as measuring devices. The measuring sample was a test piece of 2.6 mm wide × 80 mm long cut out from the prepreg described in the above-mentioned production method. The difference in dielectric dissipation factor and dielectric constant between Comparative Example 8 not containing copolymer (A) and copolymer (B) and each example or comparative example (Comparative Example 8 - Example or Comparative Example) was used for evaluation. The "-" in the table means that the varnish was dissolved and leftovers were produced during the production process and could not be evaluated. [Evaluation criteria] Dielectric dissipation factor (Df) ◎: 0.0014 or more ○: 0.0012 or more but less than 0.0014 Δ: 0.0011 or more but less than 0.0012 ×: less than 0.0011 Dielectric constant (Dk) ◎: 0.25 or more ○: 0.15 or more but less than 0.25 Δ: 0.1 or more but less than 0.15 ×: less than 0.1

<(4) Heat resistance (glass transition temperature: Tg)> The dynamic viscoelasticity of the resin composition was measured, and the temperature at which tanδ became maximum was determined as the glass transition temperature (Tg). A higher Tg means higher strength over a wider temperature range. The measuring device used was ARES (manufactured by TA Instruments, trade name), and the cured product of the above-mentioned prepreg was cut into pieces with a length of 40 mm, a width of about 10 mm, and a thickness of 0.7 mm for use as the measuring sample. The measurement was performed in the torsional mode at a frequency of 10 rad/s and a measuring temperature of -150 to 270°C. Evaluation was performed based on the difference in Tg between Comparative Example 8 without copolymer (A) and copolymer (B) and each Example or Comparative Example (Comparative Example 8 - Example or Comparative Example). The "-" in the table means that the varnish was dissolved and left over during preparation and could not be evaluated. [Evaluation criteria] ◎: Less than 10°C ○: 10°C or more and less than 25°C Δ: 25°C or more and less than 40°C ×: 40°C or more

<(5) Adhesion to copper foil (peel strength)> The following resin compositions were applied to a polyimide film, and after the solvent was dried and removed, a copper foil with a thickness of 35 μm was superimposed and the copper foil was laminated by heating and pressing at 100°C and 1 MPa for 2 minutes to produce a laminate comprising a polyimide film-resin composition-copper foil. The laminate was heated at 180°C for 1 hour to cure the resin composition, and the cured laminate was provided to an adhesion sample. A 1 cm wide incision was cut in the above laminate, and the copper foil was peeled off in a 90° direction at a tensile speed of 50 mm/min to measure the peeling strength. The higher the peeling strength value, the higher the adhesion to the copper foil. The test results were evaluated according to the following criteria. The "-" in the table means that the varnish was dissolved and left during the preparation and could not be evaluated. [Evaluation criteria] ◎: 0.8 N/mm or more ○: 0.6 N/mm or more and less than 0.8 N/mm Δ: 0.4 N/mm or more and less than 0.6 N/mm ×: less than 0.4 N/mm

<(6) Crack resistance> The varnish of the resin composition obtained above was impregnated onto a low-dielectric glass cloth having a thickness of 0.069 mm, and dried at 165°C for 5 minutes using a dryer (pressure-resistant explosion-proof steam dryer, manufactured by Takasugi Seisakusho Co., Ltd.) to obtain a prepreg having a content of 30% by mass of the resin composition. Two sheets of the prepreg were stacked, and 12 μm copper foil (3EC-M3-VLP, manufactured by Mitsui Metal & Mining Co., Ltd.) was placed on both sides. The prepreg was vacuum pressed at a pressure of 30 kg/ ^cm2 and a temperature of 210°C for 150 minutes to obtain a copper foil laminate (metal foil laminate) having a thickness of 0.2 mm.

A 0.1 mm thick aluminum foil was placed on the top of two stacked copper foil laminates, and a 1.5 mm thick paper-based phenolic resin laminate (FL-101, manufactured by FUTAMURA CHEMICAL) was placed on the bottom. Five guide holes were made at random locations using a drill with a diameter of 0.2 mm (ND-1V212, manufactured by Hitachi Via Mechanics) at a rotation speed of 160 krpm, a feed speed of 2 m/min, and a chip load of 12.5 μm/rev. The presence of turtle cracks was evaluated by SEM observation.

[Presence of cracking] The SEM images were used to observe whether cracking occurred at the bottom of the five guide holes. The ones with fewer cracking were considered to have good hole processing properties and were evaluated as follows. In addition, "-" in the table means that the varnish was dissolved and left behind during the preparation and could not be evaluated. ○: No cracking Δ: Slightly left cracking, but the number of cracking was reduced compared to Comparative Example 8 which did not contain copolymer (A) and copolymer (B). ×: There was cracking and the number of cracking was equal to or greater than that of Comparative Example 8 which did not contain copolymer (A) and copolymer (B).

The evaluation results of Examples 1 to 25, 30 to 34, and Comparative Examples 1 to 8 are shown in the following table. In addition, in the following Examples and Comparative Examples, the polymer blocks constituting the copolymers are as follows. a, d: polymer blocks mainly composed of vinyl aromatic monomer units b1, b2, e: random polymer blocks containing vinyl aromatic monomer units and covalent diene monomer units c1, c2, f: polymer blocks mainly composed of covalent diene monomer units

In the following table, the amounts of copolymer (A) and copolymer (B) are expressed as mass fractions (mass %) relative to the total amount of copolymer (A) and copolymer (B) (100 mass %). Also, the amounts of components (I) to (III) are expressed as mass parts when the total amount of copolymer (A) and copolymer (B) is 100 mass parts.

[Table 1] Example No. Embodiment 1 Embodiment 2 Embodiment 3 Embodiment 4 Embodiment 5 Embodiment 6 Low molecular weight A number A1 A2 A2 A2 A3 A4 Structure de df df df df de Number average molecular weight 30000 30000 30000 30000 8000 30000 Vinyl bonding amount (%) 60 60 60 60 75 60 Styrene content (mass %) 36 20 20 20 15 28 Hydrogenation rate (%) 98 98 98 98 98 98 Styrene block content (mass %) 20 20 20 20 15 20 Polymer B number B1 B2 B2 B2 B3 B4 Structure a-b1-a-b2 a-b1-a-c1 a-b1-a-c1 a-b1-a-c1 a-c1-a-c2 a-b1-a-b2 Number average molecular weight 150000 150000 150000 150000 90000 150000 Vinyl bonding amount (%) 60 60 60 60 75 60 Styrene content (mass %) 36 34 34 34 15 28 Hydrogenation rate (%) 98 98 98 98 98 98 Styrene block content (mass %) 20 20 20 20 15 20 ΔBS 0 0 0 0 0 0 Mnb/Mna 5.00 5.00 5.00 5.00 11.25 5.00 Average styrene content (mass %) 36 30 33 27 15 28 Average vinyl bonding content (%) 60 60 60 60 75 60 Average hydrogenation rate (%) 98 98 98 98 98 98 HV 38 38 38 38 twenty three 38 Copolymer (A) (mass %) 30 30 10 50 30 30 Copolymer (B) (mass %) 70 70 90 50 70 70 PPE(mass) 125 125 125 125 125 125 Triallyl isocyanate (wt%) 25 25 25 25 25 25 Perbutyl P (weight) 1.5 1.5 1.5 1.5 1.5 1.5 Varnish solubility ○ ○ Δ ○ ○ ○ Varnish preservation stability ◎ ◎ ○ ◎ ○ ◎ Dk ○ ◎ ◎ ○ ◎ ◎ Df ○ ◎ ◎ ○ ◎ ◎ Heat resistance (Tg) ○ ◎ ◎ ○ ○ ◎ Peel strength ○ ◎ ◎ ◎ ◎ ◎ Turtle crack resistance Δ ○ ○ ○ ○ Δ

[Table 2] Example No. Embodiment 7 Embodiment 8 Embodiment 9 Embodiment 10 Embodiment 11 Embodiment 12 Low molecular weight A number A5 A6 A7 A8 A1 A9 Structure de de de de de de Number average molecular weight 8000 35000 30000 30000 30000 30000 Vinyl bonding amount (%) 60 60 60 30 60 60 Styrene content (mass %) 36 36 32 36 36 36 Hydrogenation rate (%) 98 98 98 98 98 70 Styrene block content (mass %) 20 20 25 20 20 20 Polymer B number B5 B1 B6 B7 B8 B9 Structure a-b1-a-b2 a-b1-a-b2 a-b1-a-b2 a-b1-a-b2 a-b1-a a-b1-a-b2 Number average molecular weight 300000 150000 220000 150000 150000 150000 Vinyl bonding amount (%) 60 60 60 30 60 60 Styrene content (mass %) 36 36 19 36 36 36 Hydrogenation rate (%) 98 98 98 98 98 70 Styrene block content (mass %) 20 20 10 20 20 20 ΔBS 0 0 15 0 0 0 Mnb/Mna 37.50 4.29 7.33 5.00 5.00 5.00 Average styrene content (mass %) 36 36 twenty three 36 36 36 Average vinyl bonding content (%) 60 60 60 30 60 60 Average hydrogenation rate (%) 98 98 98 98 98 70 HV 38 38 38 68 38 10 Copolymer (A) (mass %) 50 30 30 30 30 30 Copolymer (B) (mass %) 50 70 70 70 70 70 PPE(mass) 125 125 125 125 125 125 Triallyl isocyanate (wt%) 25 25 25 25 25 25 Perbutyl P (weight) 1.5 1.5 1.5 1.5 1.5 1.5 Varnish solubility ○ ○ ○ ○ ○ ○ Varnish preservation stability ◎ ◎ ○ ◎ ◎ Δ Dk ◎ ○ ◎ ○ ○ ○ Df ◎ ○ ◎ ○ ○ ○ Heat resistance (Tg) ◎ ○ ◎ ○ ○ ◎ Peel strength ○ ○ ○ ○ Δ ○ Turtle crack resistance Δ Δ Δ Δ Δ Δ

[Table 3] Example No. Embodiment 13 Embodiment 14 Embodiment 15 Embodiment 16 Embodiment 17 Embodiment 18 Low molecular weight A number A10 A1 X1 A4 A12 A10 Structure de de de de de de Number average molecular weight 30000 30000 18000 30000 30000 30000 Vinyl bonding amount (%) 60 60 60 60 40 60 Styrene content (mass %) 36 36 36 28 50 36 Hydrogenation rate (%) 0 98 98 98 98 0 Styrene block content (mass %) 20 20 20 20 20 20 Polymer B number B10 B11 X1 B13 B4 B12 Structure a-b1-a-b2 a-b1-a-b2 a-b1-a-b2 a-b1-a-b2 a-b1-a-b2 a-b1-a Number average molecular weight 150000 100000 150000 150000 150000 110000 Vinyl bonding amount (%) 60 60 60 40 60 60 Styrene content (mass %) 36 36 36 50 28 36 Hydrogenation rate (%) 0 98 98 98 98 0 Styrene block content (mass %) 20 20 20 20 20 20 ΔBS 0 0 0 0.00 0 0 Mnb/Mna 5.00 3.33 8.33 5.00 5.00 3.67 Average styrene content (mass %) 36 36 36 39 35 36 Average vinyl bonding content (%) 60 60 60 50 54 60 Average hydrogenation rate (%) 0 98 98 98 98 0 HV -60 38 38 48 44 -60 Copolymer (A) (mass %) 30 30 30 50 30 30 Copolymer (B) (mass %) 70 70 70 50 70 70 PPE(mass) 125 125 125 125 125 125 Triallyl isocyanate (wt%) 25 25 25 25 25 25 Perbutyl P (weight) 1.5 1.5 1.5 1.5 1.5 1.5 Varnish solubility ○ ○ ○ ○ ○ ○ Varnish preservation stability Δ ◎ ◎ ◎ ◎ Δ Dk Δ ○ ○ ○ ○ Δ Df Δ Δ ○ ○ ○ Δ Heat resistance (Tg) ◎ Δ ○ ○ ○ Δ Peel strength ○ ◎ ○ ◎ ○ Δ Turtle crack resistance Δ Δ Δ Δ Δ Δ

[Table 4] Example No. Embodiment 19 Embodiment 20 Embodiment 21 Embodiment 22 Embodiment 23 Embodiment 24 Embodiment 25 Low molecular weight A number A1 A10 A10 A2 A2 A2 A2 Structure de de de df df df df Number average molecular weight 30000 30000 30000 30000 30000 30000 30000 Vinyl bonding amount (%) 60 60 60 60 60 60 60 Styrene content (mass %) 36 36 36 20 20 20 20 Hydrogenation rate (%) 98 0 0 98 98 98 98 Styrene block content (mass %) 20 20 20 20 20 20 20 Polymer B number B16 B17 B18 B2 B2 B2 B2 Structure a-b1-a a-b1-a-b2 a-b1-a a-b1-a-c1 a-b1-a-c1 a-b1-a-c1 a-b1-a-c1 Number average molecular weight 110000 110000 150000 150000 150000 150000 150000 Vinyl bonding amount (%) 60 60 60 60 60 60 60 Styrene content (mass %) 36 36 36 34 34 34 34 Hydrogenation rate (%) 98 0 0 98 98 98 98 Styrene block content (mass %) 20 20 20 20 20 20 20 ΔBS 0 0 0 0 0 0 0 Mnb/Mna 3.67 3.67 5.00 5.00 5.00 5.00 5.00 Average styrene content (mass %) 36 36 36 30 30 30 30 Average vinyl bonding content (%) 60 60 60 60 60 60 60 Average hydrogenation rate (%) 98 0 0 98 98 98 98 HV 38 -60 -60 38 38 38 38 Copolymer (A) (mass %) 30 30 30 30 30 30 30 Copolymer (B) (mass %) 70 70 70 70 70 70 70 PPE(mass) 125 125 125 - 125 125 - Triallyl isocyanate (wt%) 25 25 25 25 - 25 25 Perbutyl P (weight) 1.5 1.5 1.5 1.5 1.5 - - Varnish solubility ○ ○ ○ ○ ○ ○ ○ Varnish preservation stability ◎ Δ Δ ○ ◎ ○ ◎ Dk ○ Δ Δ ◎ ◎ ◎ ◎ Df Δ Δ Δ ◎ ◎ ◎ ◎ Heat resistance (Tg) Δ Δ ○ Δ Δ Δ Δ Peel strength Δ ◎ Δ ○ ○ ○ ○ Turtle crack resistance Δ Δ Δ Δ ○ ○ Δ

[Table 5] Example No. Embodiment 30 Embodiment 31 Embodiment 32 Embodiment 33 Embodiment 34 Low molecular weight A number A15 A16 A17 A18 A17 Structure df df df df df Number average molecular weight 30000 30000 10000 30000 10000 Vinyl bonding amount (%) 60 60 60 30 60 Styrene content (mass %) 20 20 20 20 20 Hydrogenation rate (%) 0 30 0 0 0 Styrene block content (mass %) 20 20 20 20 20 Polymer B number B19 B20 B19 B21 B22 Structure a-b1-a-c1 a-b1-a-c1 a-b1-a-c1 a-b1-a-c1 a-c1-a-c2 Number average molecular weight 150000 150000 150000 150000 90000 Vinyl bonding amount (%) 60 60 60 30 60 Styrene content (mass %) 34 34 34 34 15 Hydrogenation rate (%) 0 30 0 0 0 Styrene block content (mass %) 20 20 20 20 15 ΔBS 0 0 0 0 5 Mnb/Mna 5.00 5.00 15.00 5.00 9.00 Average styrene content (mass %) 30 30 30 27 17 Average vinyl bonding content (%) 60 60 60 30 60 Average hydrogenation rate (%) 0 30 0 0 0 HV -60 -30 -60 -30 -60 Copolymer (A) (mass %) 30 30 30 50 30 Copolymer (B) (mass %) 70 70 70 50 70 PPE(mass) 125 125 125 125 125 Triallyl isocyanate (wt%) 25 25 25 25 25 Perbutyl P (weight) 1.5 1.5 1.5 1.5 1.5 Varnish solubility ○ ○ ○ ○ ○ Varnish preservation stability Δ Δ Δ Δ Δ Dk Δ Δ Δ Δ Δ Df Δ Δ Δ Δ Δ Heat resistance (Tg) ◎ ◎ ◎ ◎ ○ Peel strength ◎ ◎ ◎ ◎ ◎ Turtle crack resistance ○ ○ ○ ○ ○

[Table 6] Example No. Comparison Example 1 Comparison Example 2 Comparison Example 3 Comparison Example 4 Comparison Example 5 Comparison Example 6 Comparative Example 7 Comparative Example 8 Low molecular weight A number RICON100 - A11 A12 A13 A14 A1 - Structure e without de de de e de - Number average molecular weight 4500 - 50000 30000 30000 30000 30000 - Vinyl bonding amount (%) 70 - 60 40 60 60 60 - Styrene content (mass %) 25 - 36 50 37 20 28 - Hydrogenation rate (%) 0 - 98 98 98 98 98 - Styrene block content (mass %) 0 - 20 20 30 0 20 - Polymer B number - B1 B1 B13 B14 B1 B15 - Structure without a-b1-a-b2 a-b1-a-b2 a-b1-a-b2 b1 a-b1-a-b2 a-b1-a-b2 - Number average molecular weight - 150000 150000 150000 150000 150000 70000 - Vinyl bonding amount (%) - 60 60 40 60 60 60 - Styrene content (mass %) - 36 36 50 20 36 36 - Hydrogenation rate (%) - 98 98 98 98 98 98 - Styrene block content (mass %) - - 20 20 0 20 20 - ΔBS - - 0.00 0.00 30.00 - 0.00 - Mnb/Mna - - 3.00 5.00 5.00 - 2.33 - Average styrene content (mass %) - - 36 50 25 31 34 - Average vinyl bonding content (%) - - 60 40 60 60 60 - Average hydrogenation rate (%) - - 98 98 98 98 98 - HV - - 38 58 38 38 38 - Copolymer (A) (mass %) 30 30 50 30 30 30 30 0 Copolymer (B) (mass %) 70 70 50 70 70 70 70 0 PPE(mass) 125 125 125 125 125 125 125 125 Triallyl isocyanate (wt%) 25 25 25 25 25 25 25 25 Perbutyl P (weight) 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 Varnish solubility ○ × × ○ × × ○ ○ Varnish preservation stability Δ - - ◎ - - ○ - Dk × - - × - - ○ - Df × - - × - - Δ - Heat resistance (Tg) × - - Δ - - × - Peel strength × - - Δ - - ◎ - Turtle crack resistance × - - Δ - - Δ -

It can be clearly seen that the cured product of the copolymer (A) and the copolymer (B) used in combination has an excellent balance between dielectric properties and heat resistance. It can be seen that the cured product of the present invention is suitable for use as a printed wiring board using glass cloth and metal laminate.

[Examples and Comparative Examples of Using Epoxy/PPE as Curing Resins] (Examples 26-29), (Comparative Examples 9-11) The following components were used to prepare resin compositions according to the following preparation method.

<Copolymer (A)> Copolymers (A1), (A2), (A5) prepared in Production Examples 1, 2, and 5 Styrene butadiene copolymer ("Ricon 100 (product name)", manufactured by Cray Valley, styrene: 25% by mass, butadiene: 75% by mass, 1,2-vinyl in butadiene: 70%, number average molecular weight 4500, block styrene content: 0% by mass, hydrogenation rate: 0%) <Copolymer (B)> Copolymers (B1) to (B3) prepared in Production Examples 15 to 17. <Component (I): Hardened resin> HP-4710 (manufactured by DIC Corporation) YP-50S (manufactured by Nippon Steel Chemical Co., Ltd.) PPE prepared in Production Example 42 <Component (II): Free radical initiator> Perbutyl P (manufactured by NOF Corporation) <Component (III): Hardener> HPC-8000-65T (manufactured by DIC Corporation) <Component (IV): Additive> 4-Dimethylaminopyridine (TCI)

<Preparation of resin composition and varnish> The component ratio and physical properties are shown in the table below. First, substances other than HPC-8000-65T (manufactured by DIC Corporation) were added to toluene, stirred, and dissolved to prepare a varnish with a concentration of 20 mass % to 50 mass %. HPC-8000-65T (manufactured by DIC Corporation) was prepared by using methyl ethyl ketone (a special grade product manufactured by Wako Pure Chemical Industries, Ltd.) as a solvent to prepare a phenolic hardener solution with a concentration of 50 mass %, and then added to the above varnish and stirred to prepare the varnish. The varnish was applied to the Kapton film after mold release at a speed of 30 mm/s, and then dried at 100°C for 30 minutes in a blow dryer under a nitrogen flow to obtain a film. The obtained film was cured for 90 minutes at 200°C in a blow dryer under a nitrogen flow to obtain a cured film. The cured film was provided as an evaluation sample.

(Evaluation criteria in Examples 26 to 29 and Comparative Examples 9 to 11) ＜(1) Varnish solubility＞ The resin composition prepared according to the composition shown in the following table was added to toluene in such a manner that the solid content concentration was 30 mass % and 50 mass %, respectively, and stirred at 40°C for 120 minutes to obtain a solution. The solutions were evaluated according to three stages. [Evaluation criteria] ○: No dissolved residue was found in the solutions with a solid content concentration of 30 mass % and 50 mass %. Δ: No dissolved residue was found in the solution with a solid content concentration of 30 mass %. ×: Dissolved residue was found in all solutions.

<(2) Dielectric properties> The dielectric dissipation factor of the obtained cured film at 10 GHz was measured by the cavity resonance method. A network analyzer (N5230A, manufactured by Agilent Technologies) and a cavity resonator (Cavity Resornator CP series) manufactured by Kanto Electronics Application Development Co., Ltd. were used as measuring devices. The test sample was a test piece of 2.6 mm wide × 80 mm long cut out from the cured film described in the above adjustment method. The difference in dielectric dissipation factor and dielectric constant between Comparative Example 11 not containing copolymer (A) and copolymer (B) and each example or comparative example (Comparative Example 11 - Example or Comparative Example) was used for evaluation. In addition, "-" in the table indicates that the evaluation could not be performed because of the dissolution residue produced during the preparation of the varnish. [Evaluation criteria] Dielectric dissipation factor (Df) ◎: 0.0013 or more ○: 0.0010 or more but less than 0.0013 Δ: 0.0005 or more but less than 0.0010 ×: less than 0.0005 Dielectric constant (Dk) ◎: 0.4 or more ○: 0.3 or more but less than 0.4 Δ: 0.2 or more but less than 0.3 ×: less than 0.2

In the following table, the block structure is shown as follows. a, d: polymer blocks with vinyl aromatic monomer units as the main component b1, b2, e: random polymer blocks containing vinyl aromatic monomer units and covalent diene monomer units c1, c2, f: polymer blocks with covalent diene monomer units as the main component

In the following table, the amounts of copolymer (A) and copolymer (B) are expressed as mass fractions (mass %) relative to the total amount of copolymer (A) and copolymer (B) (100 mass %). Also, the amounts of components (I) to (IV) are expressed as mass parts when the total amount of copolymer (A) and copolymer (B) is 100 mass parts.

[Table 7] Example No. Embodiment 26 Embodiment 27 Embodiment 28 Embodiment 29 Low molecular weight A number A1 A2 A2 A5 Structure de df df df Number average molecular weight 30000 30000 30000 8000 Vinyl bonding amount (%) 60 60 60 75 Styrene content (mass %) 36 20 20 15 Hydrogenation rate (%) 98 98 98 98 Styrene block content (mass %) 20 20 20 15 Polymer B number B1 B2 B2 B3 Structure a-b1-a-b2 a-b1-a-c1 a-b1-a-c1 a-c1-a-c2 Number average molecular weight 150000 150000 150000 90000 Vinyl bonding amount (%) 60 60 60 60 Styrene content (mass %) 36 34 34 15 Hydrogenation rate (%) 98 98 98 98 Styrene block content (mass %) 20 20 20 15 ΔBS 0 0 0 0 Mnb/Mna 5.00 5.00 5.00 11.25 Average styrene content (wt%) 36 30 30 15 Average vinyl bonding content (%) 60 60 60 65 Average hydrogenation rate (%) 98 98 98 98 HV 38 38 38 34 Copolymer (A) (mass %) 30 30 30 30 Copolymer (B) (mass %) 70 70 70 70 Epoxy resin (HP-4710) (weight) 180 180 180 180 PPE(mass) 270 270 270 270 Phenolic resin (HPC-8000-65T) (weight) 355 355 355 355 Phenoxy resin (YP-50S) (weight) 90 90 90 90 4-Dimethylaminopyridine (wt.%) 8.9 8.9 8.9 8.9 Peroxide (Perbutyl P) (weight) 5 5 5 5 Varnish solubility ○ ○ ○ Δ Dk ○ ○ ○ ○ Df ○ ○ ○ ○

[Table 8] Example No. Comparative Example 9 Comparative Example 10 Comparative Example 11 Low molecular weight A number RICON100 - - Structure d without without Number average molecular weight 4500 - - Vinyl bonding amount (%) 70 - - Styrene content (mass %) 25 - - Hydrogenation rate (%) 0 - - Polymer B number - B1 Structure without a-b1-a~b2 without Number average molecular weight - 150000 - Vinyl bonding amount (%) - 60 - Styrene content (mass %) - 36 - Hydrogenation rate (%) - 98 - ΔBS - - - Mna/Mnb - - - Average styrene content (mass %) - - - Average vinyl bonding content (%) - - - Average hydrogenation rate (%) - - - HV - - - Copolymer (A) (mass %) 30 30 30 Copolymer (B) (mass %) 70 70 70 Epoxy resin (HP-4710) (weight) 180 180 180 PPE(mass) 270 270 270 Phenolic resin (HPC-8000-65T) (weight) 355 355 355 Phenoxy resin (YP-50S) (weight) 90 90 90 4-Dimethylaminopyridine (wt.%) 8.9 8.9 8.9 Peroxide (Perbutyl P) (weight) 5 5 5 Varnish solubility ○ × ○ Dk × - - Df × - -

It can be clearly shown that the dielectric properties of the cured product of the copolymer (A) and the copolymer (B) used in the embodiment are excellent. It can be seen that the cured product of the present invention is suitable for use as a printed wiring board using glass cloth and metal laminate. [Industrial Applicability]

The resin composition and cured product of the present invention have industrial applicability as materials for films, prepregs, electronic circuit substrates, and next-generation communication substrates.

Claims (18)

A resin composition comprising: a copolymer (A) having a vinyl aromatic monomer unit and a covalent diene monomer unit, a copolymer (B) having a vinyl aromatic monomer unit and a covalent diene monomer unit, and at least one component selected from the group consisting of the following components (I) to (III), and the resin composition satisfies the following <condition (1)> to <condition (7)>, component (I): hardening resin (excluding copolymer (A) and copolymer (B)) component (II): free radical initiator component (III): hardening agent (excluding component (I)) <condition (1)>: the number average molecular weight of the above copolymer (A) is 40,000 or less, <condition (2)>: The copolymer (A) has at least one polymer block mainly composed of vinyl aromatic monomer units, ＜Condition (3)＞: The copolymer (B) has at least one polymer block mainly composed of vinyl aromatic monomer units, ＜Condition (4)＞: The number average molecular weight of the copolymer (B) is 80,000 or more, ＜Condition (5)＞: The difference (ΔBS) between the content (BSa) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (A) and the content (BSb) (mass %) of the polymer block mainly composed of vinyl aromatic monomer units in the copolymer (B) satisfies the following relationship, ΔBS＝｜BSa－BSb｜≦20 ＜Condition (6)＞: The average value of the content of the vinyl aromatic monomer unit in the above copolymer (A) and the copolymer (B) is 40% by mass or less. ＜Condition (7)＞: The content (BSb) of the polymer block mainly composed of the vinyl aromatic monomer unit in the above copolymer (B) is 10% by mass or more. The resin composition of claim 1, wherein the average hydrogenation rate (H) (%) and the average vinyl bond content (V) (%) of the unsaturated double bonds from the conjugated diene compound contained in the above copolymer (A) and the above copolymer (B) satisfy the following relationship, V+10≦H. The resin composition of claim 1, wherein the copolymer (B) is a block copolymer of the general structure: a1-b1-a2-c1, a1-b1-a2-b2, a1-c1-a2-c2, a1-c1-a2-b1, a1 block and a2 block are polymer blocks mainly composed of vinyl aromatic monomer units, b1 block and b2 block are random polymer blocks containing vinyl aromatic monomer units and covalent diene monomer units, c1 block and c2 block are polymer blocks mainly composed of covalent diene monomer units. The resin composition of claim 1, wherein the ratio (Mnb/Mna) of the number average molecular weight (Mnb) of the copolymer (B) to the number average molecular weight (Mna) of the copolymer (A) is greater than 4. The resin composition of claim 1, wherein the copolymer (A) is a block copolymer represented by the general structural formula: d-f, d is a polymer block mainly composed of vinyl aromatic monomer units, f is a polymer block mainly composed of covalent diene monomer units. A cured product, which is a cured product of the resin composition according to any one of claims 1 to 5. A printed wiring board comprising the cured article of claim 6. A resin film comprising the hardener of claim 6. A prepreg is a composite of a substrate and the resin composition of any one of claims 1 to 5. A prepreg is a composite of a substrate and a cured product as claimed in claim 6. The prepreg as claimed in claim 9, wherein the substrate is glass cloth. The prepreg of claim 10, wherein the substrate is glass cloth. A laminate having: a hardened resin film as in claim 8, and a metal foil. A laminate having: a cured product of the prepreg of claim 9, and a metal foil. A laminate having: a cured product of the prepreg of claim 10, and a metal foil. A printed wiring board comprising the resin film of claim 8. A printed wiring board comprising the prepreg as claimed in claim 11. A printed wiring board comprising the prepreg as claimed in claim 12.