JP5240516B2 - Epoxy resin composition, cured product thereof, and build-up film insulating material - Google Patents

Description

  The present invention has excellent dimensional stability because of its extremely low coefficient of linear expansion in the glass region of the cured product and in the temperature region where the cured product is exposed (under thermal cycle conditions), and is also suitable for thermal shock / physical impact. The present invention relates to an excellent (toughness) epoxy resin composition.

  An epoxy resin composition containing an epoxy resin and a curing agent as an essential component exhibits excellent heat resistance and insulation in the cured product, and is therefore widely used in electronic component applications such as semiconductors and printed wiring boards. .

Among these electronic component applications, in the technical field of build-up substrates in semiconductor package substrate materials, epoxy resin compositions containing epoxy resin and curing agent as essential components instead of conventional liquid materials as resin materials used for insulating materials A so-called build-up film formed into a film is laminated and cured on a substrate. However, in order to form an insulating layer with such a single film, the cured product itself is required to have heat resistance, moisture resistance, and strength.
As a resin material having high heat resistance and high moisture resistance in such an electronic component application, for example, a technique using phenol-biphenyl aralkyl resin as an epoxy resin raw material or a curing agent for epoxy resin is known (the following patent document). 1).
However, in recent years, as signal speeds and frequencies have increased in various electronic devices, lower dielectric constants and lower dielectric loss tangents are also required for insulating materials. When epoxy resin materials are used, In this case, the dielectric constant and dielectric loss tangent cannot be sufficiently reduced due to the presence of a hydroxyl group produced during the epoxy resin curing reaction.
Therefore, by protecting the hydroxyl groups generated during this curing reaction, a low dielectric constant and low dielectric loss tangent have been realized, and in addition, phenol-phenylene aralkyl resins have been arylesterified as a technique for further improving moisture resistance. A technique using the resulting active ester compound as an epoxy resin curing agent is known (see Patent Document 2 below). However, when such an active ester compound is used as a curing agent, it can exhibit a low dielectric constant and a low dielectric loss tangent and can exhibit good moisture resistance, but due to the presence of an aralkyl group of the compound. In addition, the cross-linking density of the cured product is low, heat resistance is not sufficiently exhibited, and sufficient flame retardancy cannot be obtained despite high aromaticity.

JP 2001-64340 A JP-A-11-140167

  Therefore, the problem to be solved by the present invention is an epoxy resin composition that has a sufficiently low dielectric constant and dielectric loss tangent of a cured product as an insulating material for electronic parts, and is extremely excellent in heat resistance and flame retardancy of the cured product, And providing a cured product thereof.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors are an epoxy resin composition containing an epoxy resin (A) and a curing agent (B) as essential components, and the curing agent (B) is: The following general formula 1

（式中、Ｘは水素原子、アルキルカルボニル基、又は、アリールカルボニル基を表し、Ｒ^１〜Ｒ^３は、水素原子、炭素原子数１〜４のアルキル基、又はフェニル基を表し、Ｒ^４は水素原子又はメチル基を表し、ｎは繰り返し単位の平均で０〜１０である。但し、Ｘのうち少なくとも１つはアルキルカルボニル基又はアリールカルボニル基である。）
で表される活性エステル樹脂（ｂ）を硬化剤として用いることにより、低誘電率・低誘電正接を実現すると共に、硬化物の耐熱性及び難燃性を飛躍的に改善できることを見出し、本発明を完成するに至った。

(In the formula, X represents a hydrogen atom, an alkylcarbonyl group, or an arylcarbonyl group, R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, and R ⁴ represents Represents a hydrogen atom or a methyl group, and n is an average of repeating units of 0 to 10, provided that at least one of X is an alkylcarbonyl group or an arylcarbonyl group.
By using the active ester resin (b) represented by the formula (I) as a curing agent, it has been found that the low dielectric constant and low dielectric loss tangent can be achieved, and the heat resistance and flame retardancy of the cured product can be dramatically improved. It came to complete.

  That is, this invention is an epoxy resin composition which has an epoxy resin (A) and a hardening | curing agent (B) as an essential component, Comprising: The said hardening | curing agent (B) is the following general formula 1

（式中、Ｘは水素原子、アルキルカルボニル基、又は、アリールカルボニル基を表し、Ｒ^１〜Ｒ^３は、水素原子、炭素原子数１〜４のアルキル基、又はフェニル基を表し、Ｒ^４は水素原子又はメチル基を表し、ｎは繰り返し単位の平均で０〜１０である。但し、Ｘのうち少なくとも１つはアルキルカルボニル基又はアリールカルボニル基である。）
で表される活性エステル樹脂（ｂ）を含有することを特徴とするエポキシ樹脂組成物に関する。

(In the formula, X represents a hydrogen atom, an alkylcarbonyl group, or an arylcarbonyl group, R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, and R ⁴ represents Represents a hydrogen atom or a methyl group, and n is an average of repeating units of 0 to 10, provided that at least one of X is an alkylcarbonyl group or an arylcarbonyl group.
The epoxy resin composition characterized by containing the active ester resin (b) represented by these.

  The present invention further relates to an epoxy resin cured product obtained by curing the epoxy resin composition.

  The present invention further relates to a build-up film insulating material comprising the epoxy resin composition.

  According to the present invention, there are provided an epoxy resin composition having a sufficiently low dielectric constant and dielectric loss tangent of a cured product as an insulating material for an electronic component, and a cured product that is remarkably excellent in heat resistance and flame retardancy of the cured product. it can.

Examples of the epoxy resin (A) used in the epoxy resin composition of the present invention include bisphenol type epoxy resins such as bisphenol A type epoxy resins and bisphenol F type epoxy resins; biphenyl type epoxy resins and tetramethylbiphenyl type epoxy resins. Biphenyl type epoxy resin; phenol novolak type epoxy resin, cresol novolak type epoxy resin, bisphenol A novolak type epoxy resin, epoxidized product of condensate of phenols and aromatic aldehyde having phenolic hydroxyl group, biphenyl novolak type epoxy resin, etc. Novolac type epoxy resin; Triphenylmethane type epoxy resin; Tetraphenylethane type epoxy resin; Dicyclopentadiene-phenol addition reaction type epoxy resin; Phenol aralkyl type Epoxy resins; naphthol novolak type epoxy resin,
Naphthol aralkyl epoxy resin, naphthol-phenol co-condensed novolac epoxy resin, naphthol-cresol co-condensed novolac epoxy resin, diglycidyloxynaphthalene, structural formula

で表される４官能ナフタレン型エポキシ樹脂等の分子構造中にナフタレン骨格を有するエポキシ樹脂；リン原子含有エポキシ樹脂等が挙げられる。また、これらのエポキシ樹脂は単独で用いてもよく、２種以上を混合してもよい。

An epoxy resin having a naphthalene skeleton in a molecular structure such as a tetrafunctional naphthalene type epoxy resin represented by: a phosphorus atom-containing epoxy resin. Moreover, these epoxy resins may be used independently and may mix 2 or more types.

  Here, as the phosphorus atom-containing epoxy resin, epoxidized product of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (hereinafter abbreviated as “HCA”), HCA and quinones Epoxy product of phenol resin obtained by reacting phenolic resin, epoxy resin obtained by modifying phenol novolac type epoxy resin with HCA, epoxy resin obtained by modifying cresol novolac type epoxy resin with HCA, and bisphenol A type epoxy resin using HCA and quinone Resin obtained by modification with a phenol resin obtained by reacting with a phenol, an epoxy resin obtained by modifying a bisphenyl A type epoxy resin with a phenol resin obtained by reacting an HCA with a quinone, etc. Is mentioned.

  Among the above-described epoxy resins (A), bisphenol type epoxy resins are preferable, particularly from the viewpoint of excellent processability when used as an epoxy resin composition, and particularly excellent moldability in use for build-up adhesive films. Equivalent 160-200 g / eq. The bisphenol A type epoxy resin is particularly preferable from the viewpoints of moldability and heat resistance.

  From the viewpoint of heat resistance, an epoxy resin having a naphthalene skeleton in the molecular structure and an epoxy resin having a phosphorus primitive in the molecular structure are preferable. The epoxy equivalent of the epoxy resin having a naphthalene skeleton and the epoxy resin having a phosphorus primitive in the molecular structure is 1,000 g / equivalent or less, particularly 700 g / equivalent or less, particularly 500 g / equivalent or less from the viewpoint of heat resistance. preferable.

  Next, the curing agent (B) used in the present invention is represented by the following general formula 1

（式中、Ｘは水素原子、アルキルカルボニル基、又は、アリールカルボニル基を表し、Ｒ^１〜Ｒ^３は、水素原子、炭素原子数１〜４のアルキル基、又はフェニル基を表し、Ｒ^４は水素原子又はメチル基を表し、ｎは繰り返し単位の平均で０〜１０である。）
で表される活性エステル樹脂（ｂ）である。

(In the formula, X represents a hydrogen atom, an alkylcarbonyl group, or an arylcarbonyl group, R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, and R ⁴ represents Represents a hydrogen atom or a methyl group, and n is an average of 0 to 10 repeating units.)
It is active ester resin (b) represented by these.

  Moreover, it is preferable that the average value of n in the said General formula 1 is 1.5-4 from the point which is excellent in the heat resistance of hardened | cured material especially.

Here, the average value of n in the general formula 1 can be obtained by the following method. [How to find the average value of n]
According to GPC measurement performed under the following conditions, styrene equivalent molecular weights (α1, α2, α3, α4) corresponding to n = 1, n = 2, n = 3, and n = 4, and n = 1 and n = The ratios (β1 / α1, β2 / α2, β3 / α3, β4 / α4) to the respective theoretical molecular weights (β1, β2, β3, β4) of 2, n = 3, and n = 4 were determined, and these (β1 / The average value of α1 to β4 / α4) is obtained. The value of n is calculated by taking the value obtained by multiplying the average value by the number average molecular weight (Mn) determined by GPC as the average molecular weight.

(GPC measurement conditions)
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation
Column: Guard column “H _XL -L” manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ Tosoh Corporation “TSK-GEL G3000HXL”
+ Tosoh Corporation “TSK-GEL G4000HXL”
Detector: RI (Differential refraction diameter)
Data processing: “GPC-8020 Model II version 4.10” manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Developing solvent Tetrahydrofuran
Flow rate: 1.0 ml / min Standard: The following monodisperse polystyrene having a known molecular weight was used in accordance with the measurement manual of “GPC-8020 Model II version 4.10”.
(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
"A-1000" manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
"A-5000" manufactured by Tosoh Corporation
“F-1” manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
“F-4” manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
“F-20” manufactured by Tosoh Corporation
“F-40” manufactured by Tosoh Corporation
“F-80” manufactured by Tosoh Corporation
“F-128” manufactured by Tosoh Corporation
Sample: A 1.0 mass% tetrahydrofuran solution filtered in terms of resin solids and filtered through a microfilter (50 μl).

  Further, the active ester resin (b) specifically includes the following general formula 1 '

（式中、Ｒ^１〜Ｒ^３は、水素原子、炭素原子数１〜４のアルキル基、又はフェニル基を表し、Ｒ^４は水素原子又はメチル基を表し、ｎは繰り返し単位の平均で０〜１０である。但し、Ｘのうち少なくとも１つはアルキルカルボニル基又はアリールカルボニル基である。）で表されるフェノール樹脂（ｂ’）のフェノール性水酸基をアルキルエステル化又はアリールエステル化した構造のものであり、フェノール性水酸基に対するアルキルエステル化又はアリールエステル化の割合は、特に限定されるものではないが、８０〜９８％の範囲であることが硬化性や活性エステル樹脂（ｂ）の硬化物における耐湿性に優れる点から好ましい。

(Wherein R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, R ⁴ represents a hydrogen atom or a methyl group, and n represents an average of 0 to 0 repeating units. 10 wherein, at least one of X is an alkylcarbonyl group or an arylcarbonyl group), the phenolic hydroxyl group of the phenol resin (b ′) represented by the alkyl ester or aryl ester structure. The ratio of alkyl esterification or aryl esterification with respect to the phenolic hydroxyl group is not particularly limited, but it is in the range of 80 to 98% in the cured product of the curability and active ester resin (b). It is preferable from the point which is excellent in moisture resistance.

  Specifically, the phenol resin (b ′) used in producing the active ester resin (b) specifically includes phenols (b1) and the following structural formula.

（式中、Ｙはメトキシメチル基、クロロメチル基、ブロモメチル基、又はビニル基を表す。）で表される２官能性アラルキル化剤（ｂ２）とを、触媒の存在下に下記工程１〜工程４を必須の工程とする方法により製造することができる。

(Wherein Y represents a methoxymethyl group, a chloromethyl group, a bromomethyl group, or a vinyl group) and a bifunctional aralkylating agent (b2) represented by the following steps 1 to step in the presence of a catalyst: 4 can be produced by a method in which 4 is an essential step.

Specifically, the phenol resin (b ′) is
Step 1: reacting the phenols (b1) with the bifunctional aralkylating agent (b2) in the presence of the catalyst (c),
Step 2: After completion of the reaction, the obtained reaction product is dissolved in 1.5 to 8 times the amount of a water-insoluble organic solvent on a mass basis to obtain a phenol resin solution,
Step 3: A step of washing the phenol resin solution obtained in Step 2 with water,
Process 4: It can manufacture industrially by removing a water-insoluble organic solvent from a phenol resin solution then.

  Here, examples of the phenols (b1) include phenol, cresol, ethylphenol, i-propylphenol, t-butylphenol, o-phenylphenol, p-phenylphenol, and 2,4,6-trimethylphenol. Among these, phenol and cresol are particularly preferable from the viewpoint of heat resistance and flame retardancy. Among these, phenol and cresol are particularly preferable from the viewpoint of heat resistance and flame retardancy.

  Next, the bifunctional aralkylating agent (b2) specifically includes 4,4′-biphenylene-bismethoxymethyl, 4,4′-divinylbiphenyl, 4,4′-biphenylene-bischloromethyl, And 4,4′-biphenylene-bisbromomethyl.

  The first step is a step of reacting the phenols (b1) with the bifunctional aralkylating agent (b2) in the presence of a catalyst. The catalyst used here is preferably an acid catalyst, for example, an inorganic acid such as hydrochloric acid, sulfuric acid or phosphoric acid, an organic acid such as methanesulfonic acid, p-toluenesulfonic acid or oxalic acid, boron trifluoride, anhydrous aluminum chloride, or chloride. Examples include Lewis acids such as zinc. The amount used is preferably in the range of 0.1 to 5% by mass with respect to the total mass of the charged raw materials.

  Here, the charging ratio of the phenols (b1) and the bifunctional aralkylating agent (b2) is in the range of the former / the latter = 10/1 to 1.1 / 1 on a mass basis. The softening point of the phenol resin obtained by the reaction is preferably in the range of 50 to 180 ° C.

  The reaction in the first step is preferably performed in the presence of water or an organic solvent. The organic solvent is not particularly limited, but alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol and isobutyl alcohol, cellosolves such as methyl cellosolve and ethyl cellosolve, and aromatic hydrocarbons such as toluene and xylene , Ketones such as methyl ethyl ketone and methyl isobutyl ketone. Water and an organic solvent may be used in combination. Specifically, for example, the phenols (b1), the bifunctional aralkylating agent (b2), water and alcohols (eg, isopropyl alcohol) are charged in a reaction vessel equipped with a stirrer. Start stirring under inert gas atmosphere. The amount of water and alcohol added at this time is such that the system can be stirred. Examples include a method in which after the system is dispersed, the temperature is increased by adding a catalyst, and the reaction is held at a temperature not exceeding the reflux temperature (95 ° C.).

  From the viewpoint of suppressing coloring of the phenol resin obtained in the reaction of Step 1, an antioxidant or a reducing agent may be added to the reaction system. Although it does not specifically limit as antioxidant, For example, a hindered phenol type compound, such as a 2, 6- dialkylphenol derivative, a bivalent sulfur type compound, a phosphite type compound containing a trivalent phosphorus atom, etc. are mentioned. Can do. Examples of the reducing agent include hypophosphorous acid, phosphorous acid, thiosulfuric acid, sulfurous acid, hydrosulfite, and salts thereof.

  Next, in Step 2, after the reaction in Step 1 is completed, the obtained reaction product is 1.5 to 8 times the amount of the bifunctional aralkylating agent (b2) on a mass basis. This is a step of dissolving in a water-insoluble organic solvent to obtain a phenol resin solution. Among the water-insoluble organic solvents used here, water-insoluble aliphatic alcohols, aliphatic ethers, and aliphatic ketone organic solvents are preferable because the extraction efficiency of the target phenol resin is good. Here, examples of the water-insoluble aliphatic alcohol include 1-butanol, 2-butanol, isobutyl alcohol, isopentyl alcohol, cyclohexanol, 2-methoxyethanol, 2-ethoxyethanol, and diethylene glycol. Examples of the water-insoluble aliphatic ether include diethylene glycol diethyl ether. Examples of water-insoluble aliphatic ketones include methyl isobutyl ketone and cyclohexanone.

  Among these, a boiling point in the range of 100 to 130 ° C. is preferable from the viewpoint of good working efficiency in step 2, and specifically, 1-butanol, 2-butanol, isobutyl alcohol, isopentyl alcohol, 2 -Methoxyethanol, 2-ethoxyethanol, diethylene glycol and methyl isobutyl ketone are preferred.

  In step 1, when water or an organic solvent is used in combination, it is preferable to dehydrate water used for the reaction or condensed water and then dissolve it using a water-insoluble organic solvent. As described above, the phenol resin, which is the target product, is extracted from the reaction product with a water-insoluble organic solvent in an amount of 1.5 to 8 times the mass of the bifunctional aralkylating agent (b2). This is a process of making a solution.

  Next, step 3 is a step of washing the phenol resin solution obtained in step 2 with water. The washing with water can be performed according to a conventional method, but it is preferably performed until the pH of the phenol resin solution is 3 to 7, preferably 5 to 7. In Step 3, the catalyst used for the reaction may be preliminarily neutralized with a neutralizing agent before and during washing with water. Examples of the neutralizing agent used here include sodium hydroxide, potassium hydroxide, potassium carbonate, triethylamine and the like.

  Next, step 4 is a step of removing the water-insoluble organic solvent from the phenol resin solution to obtain the target phenol resin. Specifically, the water-insoluble organic solvent may be removed from the phenol resin solution by removing the water-insoluble organic solvent by heating and distillation under reduced pressure. The conditions at this time are preferably in the range of 150 to 200 ° C. and 3 kPa or less.

  Through the above steps 1 to 4, the following general formula 1 '

（式中、Ｒ^１〜Ｒ^３は、水素原子、炭素原子数１〜４のアルキル基、又はフェニル基を表し、Ｒ^４は水素原子又はメチル基を表し、ｎは繰り返し単位の平均で０〜１０である。但し、Ｘのうち少なくとも１つはアルキルカルボニル基又はアリールカルボニル基である。）で表されるフェノール樹脂（ｂ’）を得ることができる。

(Wherein R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, R ⁴ represents a hydrogen atom or a methyl group, and n represents an average of 0 to 0 repeating units. It is possible to obtain a phenol resin (b ′) represented by the formula: wherein at least one of X is an alkylcarbonyl group or an arylcarbonyl group.

  The phenol resin (b ') thus obtained is then reacted with an alkyl esterifying agent or an aryl esterifying agent to obtain the desired active ester resin (b).

  Examples of the alkyl esterifying agent or aryl esterifying agent to be reacted with the phenol resin (b ′) include benzoic acid, phenylbenzoic acid, methylbenzoic acid, ethylbenzoic acid, n-propylbenzoic acid, and i-propyl. Alkyl benzoic acids such as benzoic acid and t-butyl benzoic acid, and acid halides such as acid fluorides, acid chlorides, acid bromides, and acid iodides are mentioned, but the reactivity with phenolic hydroxyl groups is good. From the point of becoming a thing, it is preferable that it is a benzoic acid chloride or an alkylbenzoic acid base.

The method of reacting the phenol resin (b ′) with the alkyl esterifying agent or the aryl esterifying agent can specifically react these components in the presence of an alkali catalyst.
Examples of the alkali catalyst that can be used here include sodium hydroxide, potassium hydroxide, triethylamine, and pyridine. Of these, sodium hydroxide and potassium hydroxide are particularly preferred because they can be used in the form of an aqueous solution and the productivity is good.

  Specifically, the reaction is performed by mixing the phenol resin (b ′) with an alkyl esterifying agent or an aryl esterifying agent in the presence of an organic solvent, and dropping the alkali catalyst or an aqueous solution thereof continuously or intermittently. The method of making it react is mentioned. At that time, the concentration of the aqueous solution of the alkali catalyst is preferably in the range of 3.0 to 30%. Examples of the organic solvent that can be used here include toluene and dichloromethane.

  After completion of the reaction, if an aqueous solution of an alkali catalyst is used, the reaction solution is allowed to stand for separation, the aqueous layer is removed, and the remaining organic layer is repeated until the aqueous layer after washing becomes almost neutral, The target resin can be obtained.

  Although it does not restrict | limit especially as a compounding quantity of the epoxy resin (A) and the hardening | curing agent (B) in the epoxy resin composition of this invention, From the point that the hardened | cured material characteristic obtained is favorable, the epoxy of epoxy resin The amount of the active group in the curing agent containing the phenol resin is preferably 0.7 to 1.2 equivalents relative to 1 equivalent of the total group.

  In the epoxy resin composition of the present invention, in addition to the curing agent (B) as an epoxy resin curing agent, an amine compound, an amide compound, an acid anhydride compound, phenol as long as the effects of the present invention are not impaired. You may use together other hardening | curing agents for epoxy resins (B '), such as a system compound. In this case, the curing agent (B ′) can be used by replacing a part of the curing agent (B) with the curing agent (B ′). That is, when the curing agent (B ′) is used in combination, the total of the active hydrogen in the curing agent (B ′) and the active hydrogen and ester bond in the curing agent (B) is in the epoxy resin (A). The ratio is preferably 0.3 to 1.2 with respect to 1 mol of the epoxy group. Moreover, a hardening | curing agent (B ') can be used in the ratio used as 50 mass% or less with respect to the total mass with a hardening | curing agent (B). Alternatively, the other curing agent (B ′) may be used as a main curing agent, and the curing agent (B) may be used as a modifier for the purpose of reducing linear expansion coefficient and dielectric loss tangent / dielectric constant. In this case, the curing agent (B) can be used at a ratio of 20 to 50% by mass with respect to the total mass of the curing agent (B) and the curing agent (B ′).

Examples of amine compounds that can be used here include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, imidazole, BF ₃ -amine complex, and guanidine derivatives.
Examples of the amide compounds include polyamide resins synthesized from dimer of dicyandiamide and linolenic acid and ethylenediamine.

  Acid anhydride compounds include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, methylhexahydroanhydride Examples include phthalic acid.

  Phenol compounds include phenol novolak resin, cresol novolac resin, aromatic hydrocarbon formaldehyde resin modified phenol resin, dicyclopentadiene phenol addition resin, phenol aralkyl resin, α-naphthol aralkyl resin, β-naphthol aralkyl resin, biphenyl aralkyl resin. , Trimethylolmethane resin, tetraphenylolethane resin, naphthol novolak resin, naphthol-phenol co-condensed novolak resin, naphthol-cresol co-condensed novolak resin, aminotriazine-modified phenol resin, and the like. Specific examples of the aminotriazine-modified phenol resin include copolymers of formaldehyde and amino group-containing triazine compounds such as melamine and benzoguanamine, phenols such as phenol and cresol, and formaldehyde.

  Among these, polyhydric phenol compounds are particularly preferred because the linear expansion coefficient of the cured product is lower, and they are resistant to thermal and physical impacts and are excellent in toughness. Phenol novolac resins, cresol novolac resins, phenol aralkyl resins Α-naphthol aralkyl resin, β-naphthol aralkyl resin, biphenyl aralkyl resin, and aminotriazine-modified phenol resin are preferable.

  The epoxy resin composition of the present invention may further contain a curing accelerator (C) in addition to the components described above.

  Examples of the curing accelerator (C) that can be used here include imidazoles, tertiary amines, and tertiary phosphines.

  Specific examples of imidazoles include 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethylimidazole, 2,4-dimethylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2 -Phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 1- Vinyl-2-methylimidazole, 1-propyl-2-methylimidazole, 2-isopropylimidazole, 1-cyanomethyl-2-methyl-imidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2- Undecyl Imi Tetrazole, another such 1-cyanoethyl-2-phenylimidazole, masking imidazoles and the like.

  Specific examples of the tertiary amines include trimethylamine, triethylamine, tripropylamine, tributylamine, tetramethylbutanediamine, tetramethylpentanediamine, tetramethylhexadiamine, triethylenediamine, N, N-dimethylbenzylamine, N, N-dimethylaniline, N, N-dimethyltoluidine, N, N-dimethylanisidine, pyridine, picoline, quinoline, N, N'-dimethylaminopyridine, N-methylpiperidine, N, N'-dimethylpiperazine, 1, And 8-diazabicyclo- [5,4,0] -7-undecene (DBU).

  Specific examples of the tertiary phosphines include trimethylphosphine, triethylphosphine, tripropylphosphine, tributylphosphine, triphenylphosphine, dimethylphenylphosphine, and methyldiphenylphosphine. Among these, tertiary amines are preferable from the viewpoint of higher heat resistance of the cured product.

  Moreover, although the addition amount of a hardening accelerator (C) can be suitably adjusted with the target hardening time etc., with respect to the total mass of an above-described epoxy resin component, a hardening | curing agent component, and the said hardening accelerator (C). It is preferable that it is the range used as 0.1-2 mass%.

  The epoxy resin composition of the present invention can further use an organic solvent (D) in addition to the above-described components depending on the application. For example, when the epoxy resin composition is used as a varnish for a laminated board, the impregnation property to the base material is improved, and when used as an adhesive film for buildup, the coating property to the base material sheet is good. Become. Examples of the organic solvent (D) that can be used here include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, and acetates such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate. , Carbitols such as cellosolve and butyl carbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, N-methylpyrrolidone and the like.

  The addition amount of the organic solvent (D) can be appropriately adjusted according to the target viscosity, but the solid content concentration ([epoxy resin (A) and other epoxy resin component + curing agent (B)] / [epoxy It is preferable that the concentration of the resin (A) and the other epoxy resin component + curing agent (B) + organic solvent (D)] is 50 to 80% by mass.

The epoxy resin composition of the present invention can further use an inorganic filler in addition to the above-described components. Specific examples of the inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, and aluminum nitride. When particularly increasing the blending amount of the inorganic filler, it is preferable to use fused silica. The fused silica can be used in either a crushed shape or a spherical shape, but in order to increase the blending amount of the fused silica and to suppress an increase in the melt viscosity of the molding material, it is preferable to mainly use a spherical shape. Furthermore, in order to increase the compounding amount of the spherical silica, it is preferable to prepare so that the particle size distribution of the spherical silica becomes wider.
Here, the amount of the inorganic filler used can be appropriately selected according to the use of the epoxy resin composition.For example, in a build-up film insulating layer application, when the amount of the inorganic filler used is increased, Although the linear expansion coefficient of the cured product is lower, the adhesion with the plating layer tends to be reduced. Since the cured product of the epoxy resin composition of the present invention exhibits a remarkably low linear expansion coefficient, the amount of the inorganic filler used in the build-up film insulating layer can be kept low. For example, in the epoxy resin composition An inorganic filler can be used in the range which becomes 80 mass% or less, and can be used in the range of 20-50 mass% especially 20-30 mass%. Moreover, in a buildup film insulation layer use, since the linear expansion coefficient of the hardened | cured material is low, it can use for a buildup film, without using any inorganic filler.

  Moreover, the epoxy resin composition of this invention can add various compounding agents, such as a flame retardant, a silane coupling agent, a mold release agent, and a pigment, as needed.

  Here, examples of the flame retardant include halogen compounds, phosphorus atom-containing compounds, nitrogen atom-containing compounds, and inorganic flame retardant compounds. Specifically, halogen compounds such as tetrabromobisphenol A type epoxy resin and brominated phenol novolak type epoxy resin, trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri-2-ethylhexyl phosphate, tributoxyethyl phosphate, triphenyl phosphate, Phosphate esters such as tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, tris (2,6 dimethylphenyl) phosphate, resorcin diphenyl phosphate, ammonium polyphosphate, Condensation of polyphosphate amide, red phosphorus, guanidine phosphate, dialkylhydroxymethylphosphonate, etc. Acid ester compounds, other, phosphorus atom-containing compounds such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, phenoxyphosphazene, nitrogen atom-containing compounds such as melamine, aluminum hydroxide, Examples include inorganic flame retardant compounds such as magnesium hydroxide, zinc borate, and calcium borate.

  The epoxy resin composition of the present invention is obtained by uniformly mixing the above-described components, and can be applied to various uses such as a semiconductor sealing material, a circuit board material, a composite material, and a build-up film.

  For example, in order to prepare an epoxy resin composition for solvent-free adhesives, paints, and sealing materials, components such as a curing agent and an inorganic filler as necessary are premixed. Thereafter, the mixture can be sufficiently mixed using a stirring mixer, an extruder, a kneader, a roll or the like until uniform. In these applications, the amount of the inorganic filler used is usually in the range of 30 to 95% by mass.

  Moreover, in order to adjust the epoxy resin composition for copper-clad laminates, build-up substrates, and fiber reinforced composite materials, the epoxy resin component of the present invention, a curing agent component, a curing accelerator, and a flame retardant as necessary. It can be produced by dissolving in an organic solvent such as toluene, xylene, acetone, methyl ethyl ketone, methyl isobutyl ketone. The amount of the solvent used in this case is preferably in the range of 10 to 70% by mass in the composition varnish.

  The epoxy resin composition of the present invention thus obtained can be cured usually at a temperature of 120 ° C. or higher and 250 ° C. or lower. In particular, a temperature range of 170 to 220 ° C. is preferable from the viewpoint of good moldability.

  Among the above various applications, the epoxy resin composition of the present invention is particularly suitable for use as a buildup film insulating material and a prepreg for laminates, but it is particularly suitable for buildup because of its excellent dielectric properties and excellent heat resistance. It is useful as a film insulating material.

  Examples of the method for producing a build-up film from the build-up film insulating material of the present invention include a method in which the epoxy resin composition of the present invention is applied on a support film and dried to form a film-like insulating layer. . The film-like insulating layer thus formed can be used as a build-up film for a multilayer printed wiring board.

  The build-up film produced from the epoxy resin composition of the present invention is softened under the lamination temperature conditions (usually 70 ° C. to 140 ° C.) in the vacuum laminating method, and simultaneously with the lamination of the circuit board, It is important to show fluidity (resin flow) capable of filling the resin in the through hole, and it is preferable to blend the above-described components so as to exhibit such characteristics.

  Here, the diameter of the through hole of the multilayer printed wiring board is usually 0.1 to 0.5 mm, and the depth is usually 0.1 to 1.2 mm. Usually, the epoxy resin composition can be filled with resin in this range. It is preferable to adjust each compounding component. When laminating both surfaces of the circuit board, it is desirable to fill about 1/2 of the through hole.

  The manufacturing method of the build-up film will be described in more detail. Specifically, after preparing the varnish-like epoxy resin composition of the present invention, the varnish-like composition is applied to the surface of the support film (y). It can be manufactured by forming the layer (x) of the build-up film resin composition which is an insulating layer by applying and removing the organic solvent by a drying process such as heating or hot air blowing.

  The drying step is preferably performed so that the content of the organic solvent (D) in the layer (x) of the build-up film resin composition is 10% by mass or less, preferably 5% by mass or less. Although the drying conditions vary depending on the amount of organic solvent in the varnish, for example, a varnish containing 30 to 60% by mass of an organic solvent can be dried at 50 to 150 ° C. for about 3 to 10 minutes.

  The thickness of the formed layer (x) is usually not less than the thickness of the conductor layer. Since the thickness of the conductor layer of the circuit board is usually in the range of 5 to 70 μm, the thickness of the resin composition layer is preferably 10 to 100 μm.

  In addition, it is preferable that the layer (x) in this invention is protected by a protective film from the point which can prevent adhesion | attachment of a dust etc. to an epoxy resin composition layer surface, and a crack.

  The above-mentioned support film and protective film are made of polyolefin such as polyethylene, polypropylene and polyvinyl chloride, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyester such as polyethylene naphthalate, polycarbonate, polyimide, and further. Examples thereof include metal foil such as pattern paper, copper foil, and aluminum foil. In addition, the support film and the protective film may be subjected to a release treatment in addition to the mud treatment and the corona treatment.

  Although the thickness of a support film is not specifically limited, Usually, it is 10-150 micrometers, Preferably it is used in 25-50 micrometers. Moreover, it is preferable that the thickness of a protective film shall be 1-40 micrometers.

  The support film (y) described above is peeled off after being laminated on a circuit board or after forming an insulating layer by heat curing. If the support film (y) is peeled after the adhesive film is heat-cured, adhesion of dust and the like in the curing process can be prevented. In the case of peeling after curing, the support film is usually subjected to a release treatment in advance.

  Next, the method of manufacturing a multilayer printed wiring board using the buildup film obtained as described above is, for example, when the layer (x) is protected with a protective film, (X) is laminated on one side or both sides of the circuit board by, for example, a vacuum laminating method so as to be in direct contact with the circuit board. The laminating method may be a batch method or a continuous method using a roll. Further, the adhesive film and the circuit board may be heated (preheated) as necessary before lamination.

  The lamination conditions are such that the pressure bonding temperature (laminating temperature) is preferably 70 to 140 ° C., the pressure bonding pressure is preferably 1 to 11 kgf / cm 2 (9.8 × 10 4 to 107.9 × 104 N / m 2), and the air pressure is 20 mmHg (26 It is preferable to laminate under a reduced pressure of 0.7 hPa or less.

  Here, the circuit board has a conductive layer (circuit) patterned on one or both sides of a substrate such as a glass epoxy, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, thermosetting polyphenylene ether substrate or the like. Can be mentioned.

  After laminating the adhesive film on the circuit board in this way, when the support film (y) is peeled off, the support film (y) is peeled off and thermally cured to form an insulating layer on the circuit board. The conditions of heat curing are selected in the range of 20 to 180 minutes at 150 to 220 ° C, more preferably 30 to 120 minutes at 160 to 200 ° C.

  If the support film (y) is not peeled off after the insulating layer is formed, it is peeled off here. Next, holes are formed in the insulating layer formed on the circuit board by a method such as drilling, laser, or plasma to form via holes and through holes.

  Next, the surface of the insulating layer is roughened with an oxidizing agent. Examples of the oxidizing agent include permanganates such as potassium permanganate and sodium permanganate, dichromates, ozone, and nitric acid.

  Next, a conductor layer is formed on the surface of the resin composition layer on which uneven anchors are formed by the roughening treatment by a method combining electroless plating and electrolytic plating. Alternatively, a plating resist having a pattern opposite to that of the conductor layer may be formed, and the conductor layer may be formed only by electroless plating. After forming the conductor layer, the peel strength of the conductor layer can be further improved and stabilized by annealing at 150 to 200 ° C. for 20 to 90 minutes. In the present invention, as described above, an excellent peel strength can be exhibited because the amount of the inorganic filler used can be kept low.

  Moreover, as a method of patterning the conductor layer to form a circuit, for example, a subtractive method, a semi-additive method, or the like can be used.

  Next, a method for producing a prepreg for an interlayer insulating layer of a multilayer printed wiring board by impregnating a sheet-like reinforcing substrate made of fibers with the epoxy resin composition of the present invention includes, for example, the epoxy resin composition of the present invention. There is a method in which a sheet-like reinforcing substrate made of fiber is impregnated by a hot melt method or a solvent method and semi-cured by heating. Examples of the sheet-like reinforcing substrate made of fibers that can be used here include glass cloth and aramid fibers.

Next, a method for producing a multilayer printed wiring board using the above prepreg includes, for example, one or several prepregs of the present invention on a circuit board, and a metal plate sandwiched between release films and pressurizing / heating conditions. The method of carrying out press lamination below is mentioned. Specifically, the pressure condition is preferably 5 to 40 kgf / cm ² , and the temperature is preferably 120 to 250 ° C. and 20 to 120 minutes. Moreover, it can also be manufactured by laminating on a circuit board by a vacuum laminating method as in the case of an adhesive film, and then curing by heating. Thereafter, similar to the method described above, the surface of the prepreg cured with an oxidizing agent is roughened, and then a conductor layer is formed by plating to produce a multilayer printed wiring board.

  Hereinafter, the present invention will be described in detail in Examples and Comparative Examples. In addition, the measuring method of the property value of the epoxy resin in a following example and a comparative example is as follows.

Hereinafter, the present invention will be described in detail in Examples and Comparative Examples. In addition, the measuring method of the property value of the epoxy resin in a following example and a comparative example is as follows.
[Epoxy equivalent] Measured according to "JIS K7236 (2001)".
[Softening point] Measured according to "JIS K7234".
[ICI Viscosity] Measured according to “ASTM D4287”, the melt viscosity at 150 ° C. was measured.
[GPC]
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation
Column: Guard column "H _XL- L" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ Tosoh Corporation “TSK-GEL G3000HXL”
+ Tosoh Corporation “TSK-GEL G4000HXL”
Detector: RI (differential refractive diameter) Data processing: “GPC-8020 model II version 4.10” manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Developing solvent Tetrahydrofuran Flow rate 1.0 ml / min Standard: The following monodisperse polystyrene having a known molecular weight was used according to the measurement manual of “GPC-8020 Model II version 4.10”.
(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
"A-1000" manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
"A-5000" manufactured by Tosoh Corporation
“F-1” manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
“F-4” manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
“F-20” manufactured by Tosoh Corporation
“F-40” manufactured by Tosoh Corporation
“F-80” manufactured by Tosoh Corporation
“F-128” manufactured by Tosoh Corporation
Sample: A 1.0 mass% tetrahydrofuran solution filtered in terms of resin solids and filtered through a microfilter (50 μl).

[FT-IR] A well-ground sample is uniformly mixed with KBr dehydrated powder (agate mortar), placed in a molder, vacuum-pressed to make a transparent tablet, and "FT / IR-" manufactured by JASCO Corporation. 550 ".

[Synthesis Example 1]
The following structural formula is attached to a flask equipped with a thermometer, dropping funnel, condenser, fractionator, and stirrer.

で表されるビフェニルアラルキル樹脂（明和化成製「ＭＥＨＣ−７８５１ＳＳ」水酸基当量：２０２（固形分値）、軟化点６５℃（固形分値）、上記構造式中のｎの平均２）１７９ｇとメチルイソブチルケトン［以下ＭＩＢＫと記す。］８１８ｇを仕込み系内を減圧窒素置換し溶解させた。次いで、塩化ベンゾイル１２６．５ｇ（０．９０モル）を仕込み、系内を減圧窒素置換し溶解させた。その後、テトラブチルアンモニウムブロマイドを０．５４ｇを溶解させ、窒素ガスパージを施しながら、系内を６０℃以下に制御して、２０％水酸化ナトリウム水溶液１８１．８ｇを３時間かけて滴下した。次いでこの条件下で１．０時間撹拌を続けた。反応終了後、静置分液し、水層を取り除いた。更に反応物が溶解しているＭＩＢＫ相に水を投入して約１５分間撹拌混合し、静置分液して水層を取り除いた。水槽のＰＨが７になるまでこの操作を繰り返した。その後、デカンタ脱水で水分を除去し、続いて減圧脱水でＭＩＢＫを除去し、活性エステル樹脂（Ａ−１）を合成した。この樹脂（Ａ−１）の官能基当量２９６、軟化点は８０℃であった。

179 g of biphenyl aralkyl resin (Maywa Kasei "MEHC-7851SS" hydroxyl equivalent: 202 (solid content value), softening point 65 ° C. (solid content value), average 2 of n in the above structural formula) and methyl isobutyl Ketone [hereinafter referred to as MIBK. 818 g was charged and the inside of the system was purged with nitrogen under reduced pressure to dissolve. Next, 126.5 g (0.90 mol) of benzoyl chloride was charged, and the inside of the system was purged with nitrogen under reduced pressure to dissolve. Thereafter, 0.54 g of tetrabutylammonium bromide was dissolved, and the inside of the system was controlled to 60 ° C. or lower while performing a nitrogen gas purge, and 181.8 g of a 20% aqueous sodium hydroxide solution was added dropwise over 3 hours. Stirring was then continued for 1.0 hour under these conditions. After completion of the reaction, the solution was allowed to stand for separation, and the aqueous layer was removed. Further, water was added to the MIBK phase in which the reaction product was dissolved, and the mixture was stirred and mixed for about 15 minutes. This operation was repeated until the pH of the water tank reached 7. Thereafter, water was removed by decanter dehydration, and subsequently MIBK was removed by vacuum dehydration to synthesize an active ester resin (A-1). This resin (A-1) had a functional group equivalent of 296 and a softening point of 80 ° C.

Example 1 and Comparative Examples 1 and 2 (Adjustment of epoxy resin composition and evaluation of physical properties)
In accordance with the formulation shown in Table 1 below, an epoxy resin and an ester compound were blended, and 0.5 phr of dimethylaminopyridine was further added as a curing catalyst. Finally, the nonvolatile content (NV) of each composition was 58% by mass. It adjusted by mix | blending methyl ethyl ketone so that it might become. This was transferred to an aluminum petri dish and dried at 120 ° C. to remove methyl ethyl ketone to obtain a semi-cured product. Next, the semi-cured product is put into a 15 cm × 15 cm × 2 mm mold and vacuum press-molded (temperature conditions: 200 ° C., pressure: 40 kg / cm ² , molding time: 1.5 hours) to obtain a plate-shaped cured product. Obtained. Using this as a test piece, the following various evaluations were performed. The results are shown in Table 1.

[Flame retardance test]
Ignition for 10 seconds at one end of a test piece molded to 1 × 10 cm. Visual observation of specimen state after natural fire extinguishing ○: Carbonized but maintained specimen shape ×: Complete combustion. Or complete disappearance [heat resistance test]
Glass transition temperature: The test piece was measured by the DMA method. Temperature rising speed 3 ° C / min.
[Measurement of dielectric constant and dissipation factor]
In accordance with JIS-C-6481, the dielectric material at 1 GHz of the test piece after being stored in an indoor room at 23 ° C. and 50% humidity for 24 hours after absolutely dry using an impedance material analyzer “HP4291B” manufactured by Agilent Technologies, Inc. The rate and dielectric loss tangent were measured.

Each component in Table 1 is as follows.
“TD-2090”: phenol novolak resin (hydroxyl equivalent: 105 g / eq., Softening point 120 ° C., average number of nuclei 8)
Biphenyl aralkyl resin: biphenyl aralkyl resin used in Synthesis Example 1

Claims (8)

An epoxy resin composition comprising an epoxy resin (A) and a curing agent (B) as essential components, wherein the curing agent (B) is represented by the following general formula 1

(In the formula, X represents a hydrogen atom, an alkylcarbonyl group, or an arylcarbonyl group, R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, and R ⁴ represents Represents a hydrogen atom or a methyl group, and n is an average of repeating units of 0 to 10, provided that at least one of X is an alkylcarbonyl group or an arylcarbonyl group.
The epoxy resin composition characterized by including the active ester resin (b) represented by these. The active ester resin (b) is represented by the following general formula 1 ′

(Wherein R ^{1 to} R ³ represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or a phenyl group, R ⁴ represents a hydrogen atom or a methyl group, and n represents an average of 0 to 0 repeating units. 10)
The epoxy resin composition according to claim 1, which has a molecular structure obtained by alkylesterifying or arylesterifying 80 to 98% of the phenolic hydroxyl group of the phenolic resin (b ') represented by formula (1).   The epoxy resin composition according to claim 2, wherein the active ester resin (b) is obtained by reacting a phenol resin (b ') with a benzoic acid chloride or an alkylbenzoic acid base.   The epoxy resin composition according to claim 1, 2, or 3, wherein the active ester resin (b) has a softening point in the range of 60 to 135 ° C. The epoxy resin composition according to any one of claims 1 to 4, further comprising a curing accelerator (C) in addition to the epoxy resin (A) and the curing agent (B). Any one of Claims 1-5 which contains an organic solvent (D) in the ratio from which solid content concentration (ratio of A + B) will be 50-80 mass% in addition to an epoxy resin (A) and a hardening | curing agent (B). The epoxy resin composition as described in any one. A cured epoxy resin product obtained by curing the epoxy resin composition according to any one of claims 1 to 6. A buildup film insulating material comprising the epoxy resin composition according to any one of claims 1 to 6.