CN118715250A - Optical moisture curing resin composition, adhesive for electronic components, and adhesive for display element - Google Patents

Abstract

A light moisture curable resin composition comprising a radical polymerizable compound, a moisture curable resin, a light radical polymerization initiator, and zirconium nitride, wherein the OD value of a cured product having a thickness of 1 mm after curing is 2 or more.

Description

Optical moisture curing resin composition, adhesive for electronic components and adhesive for display elements

Technical Field

The present invention relates to an optical moisture curing resin composition, an adhesive for electronic components, and an adhesive for display elements.

Background Art

In recent years, electronic devices such as televisions, PCs, and smartphones have been required to be highly integrated and miniaturized, and thus the frame of display elements (hereinafter also referred to as "displays") tends to be narrower. As a means of accepting such a trend and bonding electronic components to liquid crystal cells, it is believed that the use of adhesives instead of the double-sided tapes used in the past has become the mainstream, and optical moisture curing adhesives in particular have attracted attention from the perspectives of workability and final bonding strength.

However, when the optical moisture curing adhesive is used around a display element, for example, light shielding properties are sometimes required to prevent a decrease in contrast due to light leakage. Therefore, for example, Patent Document 1 discloses an optical moisture curing resin composition having excellent light shielding properties and adhesiveness, and in this disclosure, as a means of imparting light shielding properties, it is proposed to use titanium black or the like as a light shielding agent to blacken the optical moisture curing resin composition.

In addition, the light moisture curing adhesive has the disadvantage that it does not show sufficient adhesion (initial adhesion) just after lamination like a double-sided tape, and it takes time to bond the components to each other. Therefore, in the past, a light moisture curing resin composition that can show excellent initial adhesion just after light curing has been studied. For example, Patent Document 2 discloses a light moisture curing resin composition that is applied linearly to a polycarbonate plate and a glass plate is bonded via the composition just after light curing, so that the ratio of the width of the bonding portion in each plate (internal and external ratio) is within a certain range, and the viscosity is also within a certain range.

Prior art literature

Patent Literature

Patent Document 1: International Publication No. 2015/111570

Patent Document 2: International Publication No. 2021/230372

Summary of the invention

Problems to be solved by the invention

However, conventional optical moisture curable resin compositions have a problem in that, when blackening is performed to impart light-shielding properties, photocurability becomes insufficient, and it is difficult to sufficiently improve initial adhesive strength, for example.

Therefore, the present invention aims to provide an optical moisture curable resin composition having high photocurability even when blackening is performed to impart light-shielding properties.

Means for solving problems

The present inventors conducted intensive research and found that the above-mentioned problems can be solved by using the following optical moisture curing resin composition, which contains a free radical polymerizing compound, a moisture curing resin, a photo radical polymerization initiator, and zirconium nitride, and the OD value of the cured product with a thickness of 1 mm after photocuring is greater than 2, and completed the present invention.

The present invention provides the following [1] to [19].

[1] An optical moisture-curable resin composition comprising: a radical polymerizable compound, a moisture-curable resin, a photoradical polymerization initiator, and zirconium nitride, wherein the OD value of a cured product having a thickness of 1 mm after photocuring is 2 or more.

[2] The optical moisture curable resin composition according to [1], wherein the content of the zirconium nitride is 0.1 parts by mass or more and 1.5 parts by mass or less relative to 100 parts by mass of the total amount of the radical polymerizable compound and the moisture curable resin.

[3] The optical moisture curable resin composition according to [1] or [2], wherein the mass ratio of the moisture curable resin to the radical polymerizable compound in the optical moisture curable resin composition is 30/70 or more and 90/10 or less.

[4] The optical moisture curable resin composition according to any one of [1] to [3], wherein the total content of the radical polymerizable compound and the moisture curable resin in the optical moisture curable resin composition is 50% by mass or more based on the total amount of the optical moisture curable resin composition.

[5] The optical moisture curable resin composition according to any one of [1] to [4], wherein the content of the photoradical polymerization initiator is 0.1 parts by mass or more and 10 parts by mass or less relative to 100 parts by mass of the radical polymerizable compound.

[6] The optical moisture curable resin composition according to any one of [1] to [5], wherein the average primary particle size of the zirconium nitride is 1 nm to 700 nm.

[7] The optical moisture curable resin composition according to any one of [1] to [6], wherein the radical polymerizable compound includes a monofunctional radical polymerizable compound.

[8] The optical moisture curable resin composition according to [7], wherein the monofunctional radical polymerizable compound includes a nitrogen-containing compound.

[9] The optical moisture curable resin composition according to [8], wherein the monofunctional radical polymerizable compound contains a (meth)acrylate compound as a compound other than the nitrogen-containing compound.

[10] The optical moisture curable resin composition according to any one of [1] to [9], wherein the radical polymerizable compound includes a polyfunctional radical polymerizable compound.

[11] The optical moisture-curable resin composition according to any one of [1] to [10], wherein the moisture-curable resin is a moisture-curable urethane resin.

[12] The optical moisture curable resin composition according to any one of [1] to [11], when applied to an aluminum substrate with a line width of 1.0 mm and photocured by irradiating 1500 mJ/ ^cm2 of ultraviolet rays, and then pressed against a glass plate at 0.08 MPa for 120 seconds, if the average width of the bonding portion on the glass plate side is a and the average width of the bonding portion on the aluminum substrate side is b, then a/b is greater than 0.5 and less than 0.95.

[13] The optical moisture curable resin composition according to any one of [1] to [12], wherein the viscosity measured using a cone and plate viscometer at 25° C. and 5.0 rpm is 40 Pa·s or more and 600 Pa·s or less.

[14] The optical moisture curable resin composition according to any one of [1] to [13], further comprising a filler.

[15] An adhesive for electronic components, comprising the optical moisture curable resin composition according to any one of [1] to [14].

[16] An adhesive for a display element, comprising the optical moisture curable resin composition according to any one of [1] to [14].

[17] A cured product of the optical moisture curable resin composition according to any one of [1] to [14].

[18] Use of the optical moisture curable resin composition according to any one of [1] to [14] for electronic components.

[19] Use of the optical moisture curable resin composition according to any one of [1] to [14] for a display element.

Effects of the Invention

According to the present invention, it is possible to provide an optical moisture curable resin composition having high photocurability even when blackening is performed to impart light-shielding properties.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a conceptual diagram showing a method for measuring the internal-external ratio a/b.

FIG. 2 is a schematic diagram showing an adhesion test method, FIG. 2( a ) is a plan view, and FIG. 2( b ) is a side view.

FIG. 3 is a schematic diagram showing a method for measuring the initial creep force, wherein FIG. 3( a ) is immediately after crimping, and FIG. 3( b ) is one hour after crimping.

DETAILED DESCRIPTION

Hereinafter, the present invention will be described in detail with reference to embodiments.

[Optical moisture curing resin composition]

The optical moisture curable resin composition of the present invention contains a radical polymerizable compound, a moisture curable resin, a photoradical polymerization initiator, and zirconium nitride.

＜Zirconium Nitride＞

The optical moisture curable resin composition of the present invention contains zirconium nitride. In the present invention, even if the optical moisture curable resin composition is blackened in a manner such that the OD value becomes above a certain value as described later, the optical moisture curable resin composition can maintain high photocurability by containing zirconium nitride. The principle is uncertain, but it is presumed that the optical moisture curable resin composition contains zirconium nitride, so that the transmittance of visible light is suppressed below a certain value, and the transmittance of the low wavelength side such as ultraviolet rays becomes above a certain value, so that the light used for photocuring can be transmitted to the inside of the optical moisture curable resin composition. In addition, if the photocurability can be made high, it is also easy to make the initial adhesion good.

The average primary particle size of the zirconium nitride used in the present invention is not particularly limited, but is preferably 1 nm or more and 700 nm or less, more preferably 5 nm or more and 500 nm or less, and further preferably 10 nm or more and 100 nm or less. If the average primary particle size of the zirconium nitride is above the above lower limit, it is easy to adjust the OD value of the light moisture curable resin composition to a certain value or more. In addition, if the particle size of the zirconium nitride is below the above upper limit, the operability of the light moisture curable resin composition becomes good.

The average primary particle size can be obtained by, for example, measuring 50 or more particles using a scanning electron microscope and calculating the average value.

In the present invention, as zirconium nitride, for example, a commercially available product such as "UB-1" (manufactured by Mitsubishi Material Electronics Co., Ltd.) can be used.

The content of zirconium nitride in the optical moisture curable resin composition of the present invention is preferably 0.1 mass parts or more and 1.5 mass parts or less, more preferably 0.2 mass parts or more and 1.2 mass parts or less, and further preferably 0.3 mass parts or more and 1.0 mass parts or less, relative to 100 mass parts of the total amount of the free radical polymerizable compound and the moisture curable resin. By making the content of zirconium nitride above the above lower limit, it is easy to make the OD value described later to be above a certain value. On the other hand, by making the content of zirconium nitride below the above upper limit, it is easy to adjust the viscosity at 25°C described later to the desired range. In addition, it is also easy to improve light curing properties, adhesion, etc.

＜OD value＞

The optical density (OD value) of the cured product with a thickness of 1 mm after photocuring of the optical moisture curable resin composition of the present invention is 2 or more. If the OD value is less than 2, the light shielding property becomes insufficient, and light leakage occurs when used for display elements, etc., and sometimes a high contrast ratio cannot be obtained. The above OD value is preferably 2.5 or more, and more preferably 3 or more.

The OD value is preferably as high as possible from the viewpoint of light-shielding properties, but is preferably 7 or less, more preferably 6 or less, and more preferably 5.5 or less from the viewpoint of making the content of zirconium nitride and other colorants below a certain level so as to achieve good photocurability and making the optical moisture curable resin composition have an appropriate viscosity.

The OD value of the optical moisture curable resin composition after curing can be measured using a densitometer. The OD value is preferably measured using a sample having a thickness of 1 mm obtained by photocuring the optical moisture curable resin composition.

[Radical polymerizable compound]

The optical moisture curable resin composition of the present invention contains a radical polymerizable compound. The optical moisture curable resin composition is given photocurability by containing a radical polymerizable compound. The optical moisture curable resin composition has photocurability, so that a certain adhesive force can be given by just light irradiation, so it is easy to ensure appropriate initial adhesive force. In addition, it can be above a certain hardness by just light irradiation, and it is also easy to ensure workability.

The radical polymerizable compound may have any radical polymerizable functional group in the molecule. Suitable compounds include those having an unsaturated double bond as a radical polymerizable functional group, and examples thereof include (meth)acryloyl, vinyl, styryl, and allyl groups.

Among the above, from the viewpoint of adhesion, (meth)acryloyl is suitable, that is, the free radical polymerizable compound preferably contains a compound having a (meth)acryloyl. It should be noted that the compound having a (meth)acryloyl is also referred to as a "(meth)acrylic compound" below. In addition, in this specification, "(meth)acryloyl" refers to acryloyl or (meth)acryloyl, "(meth)acrylic" refers to acrylic or methacrylic, and other similar terms are the same.

The radical polymerizable compound may include one or both of a monofunctional radical polymerizable compound having one radical polymerizable functional group in one molecule and a polyfunctional radical polymerizable compound having two or more radical polymerizable functional groups in one molecule, but from the viewpoint of improving the initial adhesion of the light moisture curable resin composition, it is preferred to include a monofunctional radical polymerizable compound. In addition, the radical polymerizable compound more preferably includes at least a monofunctional (meth) acrylic acid compound as a (meth) acrylic acid compound as a monofunctional radical polymerizable compound. It should be noted that the monofunctional radical polymerizable compound can be a prepolymer that is polymerized and has a repeating unit, but it is generally better to use a monofunctional monomer that does not have a repeating unit.

From the viewpoint of improving the initial bonding strength of the light moisture curable resin composition, the light moisture curable resin composition preferably contains a monofunctional free radical polymerizable compound as a free radical polymerizable compound. In the case of containing a monofunctional free radical polymerizable compound as a free radical polymerizable compound in many places, the initial bonding strength can be improved because the bonding area when other adherends are pressed after light curing can be large. Specifically, from the viewpoint of improving the initial bonding strength, the content of the monofunctional free radical polymerizable compound in the light moisture curable resin composition is preferably 70 parts by mass or more, more preferably 80 parts by mass or more, further preferably 90 parts by mass or more, and particularly preferably 95 parts by mass or more relative to 100 parts by mass of the free radical polymerizable compound. In addition, from the viewpoint of improving the initial bonding strength, the upper limit of the above-mentioned content of the monofunctional free radical polymerizable compound is not particularly limited, as long as it is less than 100 parts by mass.

(Monofunctional radical polymerizable compound)

The radical polymerizable compound preferably contains a nitrogen-containing compound as a monofunctional radical polymerizable compound. If a nitrogen-containing compound is used, the adhesive force of the light moisture curable resin composition tends to become good. After being applied to an adherend, the light moisture curable resin composition is irradiated with active energy rays such as ultraviolet rays and photocured. At this time, it is generally often photocured in the presence of oxygen as described later. If the radical polymerizable compound contains a nitrogen-containing compound, it is appropriately photocured even in the presence of oxygen, and thus, it is estimated that the adhesive force becomes good.

The nitrogen-containing compound may contain one or both of a chain nitrogen-containing compound and a nitrogen-containing compound having a cyclic structure, but from the viewpoint of improving the adhesive strength of the optical moisture curable resin composition, it is preferred to contain a nitrogen-containing compound having a cyclic structure, and it is more preferred to use a chain nitrogen-containing compound and a nitrogen-containing compound having a cyclic structure in combination.

As the nitrogen-containing compound with a cyclic structure, there can be mentioned nitrogen-containing compounds with lactam structures such as N-vinylpyrrolidone and N-vinyl-ε-caprolactam, compounds containing morpholine skeletons such as N-acryloylmorpholine, cyclic imide compounds such as N-(methyl)acryloyloxyethylhexahydrophthalimide, etc. Among them, specifically, compounds containing amide groups such as N-vinyl-ε-caprolactam are further preferred. It should be noted that in this specification, the nitrogen-containing compound with a cyclic structure is also referred to as a cyclic nitrogen-containing compound, and the free radical polymerizable compound in which the nitrogen atom is contained in the atoms constituting the ring itself is regarded as a cyclic nitrogen-containing compound, and other nitrogen-containing compounds are regarded as chain nitrogen-containing compounds.

Examples of the chain nitrogen-containing compound include chain (meth)acrylates containing an amino group such as dimethylamino (meth)acrylate, diethylamino (meth)acrylate, aminomethyl (meth)acrylate, aminoethyl (meth)acrylate, and dimethylaminoethyl (meth)acrylate; chain (meth)acrylamide compounds such as diacetone acrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, N-isopropylacrylamide, N-hydroxyethylacrylamide, acrylamide, and methacrylamide; and N-vinylacetamide.

In addition, as the chain nitrogen-containing compound, a monofunctional carbamate (meth) acrylate may be used. By using a monofunctional carbamate (meth) acrylate, when a carbamate resin, particularly a carbamate resin having a polycarbonate skeleton, is used as a moisture-curable resin, the compatibility with the moisture-curable resin becomes good, and the adhesive force is easily improved. In addition, since the carbamate (meth) acrylate has a relatively high polarity, it is particularly easy to increase the adhesive force to glass.

As the monofunctional urethane (meth)acrylate, for example, one obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group with an isocyanate compound can be used.

Examples of the (meth)acrylic acid derivative having a hydroxyl group include mono(meth)acrylates of diols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol and polyethylene glycol; and mono(meth)acrylates of triols such as trimethylolethane, trimethylolpropane and glycerol.

Examples of the isocyanate compound used to obtain the urethane (meth)acrylate include aliphatic monoisocyanates such as alkane monoisocyanates such as butane isocyanate, hexane isocyanate, and decane isocyanate, and cyclic aliphatic monoisocyanates such as cyclopentane isocyanate, cyclohexane isocyanate, and isophorone monoisocyanate.

More specifically, the monofunctional urethane (meth)acrylate is preferably a urethane (meth)acrylate obtained by reacting the above-mentioned monoisocyanate compound with a mono(meth)acrylate of a diol, and a suitable specific example thereof includes 1,2-ethylene glycol 1-acrylate 2-(N-butyl carbamate).

Among the above, the chain nitrogen-containing compound preferably includes a monofunctional urethane (meth)acrylate, and it is also preferred to use a monofunctional urethane (meth)acrylate in combination with a compound other than the monofunctional urethane (meth)acrylate, such as a (meth)acrylamide compound.

From the viewpoint of improving the adhesive force of the optical moisture curable resin composition, the content of the nitrogen-containing compound as a monofunctional free radical polymerizable compound in the optical moisture curable resin composition is preferably 10 parts by mass or more, more preferably 30 parts by mass or more, further preferably 40 parts by mass or more, and most preferably 50 parts by mass or more relative to 100 parts by mass of the free radical polymerizable compound. In addition, in order to contain an appropriate amount of free radical polymerizable compounds other than the nitrogen-containing compound, the above-mentioned content of the nitrogen-containing compound as the monofunctional free radical polymerizable compound is preferably 95 parts by mass or less, more preferably 90 parts by mass or less, and further preferably 85 parts by mass or less.

When the monofunctional free radical polymerizable compound has a chain nitrogen-containing compound and a cyclic nitrogen-containing compound, the mass ratio of the cyclic nitrogen-containing compound to the chain nitrogen-containing compound in the monofunctional free radical polymerizable compound (cyclic/chain) is preferably 0.1 to 2.0, more preferably 0.2 to 1.5, and even more preferably 0.4 to 1.2. By making the cyclic/chain mass ratio within the above range, the optical moisture curing type resin composition can have good adhesive force.

(Monofunctional radical polymerizable compounds other than nitrogen-containing compounds)

The monofunctional radical polymerizable compound contained in the radical polymerizable compound preferably includes a compound other than the above-mentioned nitrogen-containing compound (hereinafter also referred to as a non-nitrogen-containing compound). When the radical polymerizable compound contains a non-nitrogen-containing compound as a monofunctional radical polymerizable compound, adhesive strength and the like can be easily improved.

The nitrogen-free compound is not particularly limited as long as it is a compound having a radical polymerizable functional group, but a monofunctional (meth)acrylic compound is preferred, and among these, a (meth)acrylate compound is more preferred.

Examples of the monofunctional (meth)acrylate compound include alkyl (meth)acrylates, (meth)acrylates containing an alicyclic structure, (meth)acrylates containing an aromatic ring, etc. These may be used alone or in combination of two or more, but among these, it is preferred to use one or both of the alkyl (meth)acrylates and the (meth)acrylates containing an aromatic ring.

The total content of the (meth) acrylate alkyl ester, the (meth) acrylate containing an alicyclic structure, and the (meth) acrylate containing an aromatic ring in the radical polymerizable compound is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and further preferably 15 parts by mass or more, relative to 100 parts by mass of the radical polymerizable compound. In addition, the above content is preferably 90 parts by mass or less, more preferably 70 parts by mass or less, further preferably 60 parts by mass or less, and most preferably 40 parts by mass or less.

Examples of the alkyl (meth)acrylate include alkyl (meth)acrylates having an alkyl group with 1 to 18 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, isomyristyl (meth)acrylate, and stearyl (meth)acrylate.

Examples of the (meth)acrylate containing an alicyclic structure include (meth)acrylate having an alicyclic structure such as cyclohexyl (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, 3,3,5-trimethylcyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and dicyclopentenyl (meth)acrylate.

Examples of the (meth)acrylate containing an aromatic ring include benzyl (meth)acrylate, phenylalkyl (meth)acrylate such as 2-phenylethyl (meth)acrylate, and phenoxyalkyl (meth)acrylate such as phenoxyethyl (meth)acrylate.

As the monofunctional (meth)acrylate compound, in addition to (meth)acrylate alkyl esters, (meth)acrylates containing an alicyclic structure, and (meth)acrylates containing an aromatic ring, for example, (meth)acrylates containing a cyclic ether group may be used.

Examples of the (meth)acrylate containing a cyclic ether group include (meth)acrylates containing an epoxy ring, an oxetane ring, a tetrahydrofuran ring, a dioxolane ring, a dimethicone ring, and a dimethicone ring. (Meth)acrylates of alkyl rings, etc.

Examples of (meth)acrylates containing an epoxy ring include glycidyl (meth)acrylate. Examples of (meth)acrylates containing an oxetane ring include (3-ethyloxetane-3-yl)methyl (meth)acrylate. Examples of (meth)acrylates containing a tetrahydrofuran ring include tetrahydrofurfuryl (meth)acrylate and (meth)acrylic acid polymers of tetrahydrofurfuryl alcohol. Examples of (meth)acrylates containing a dioxolane ring include (2-methyl-2-ethyl-1,3-dioxolane-4-yl)methyl (meth)acrylate and (2,2-cyclohexyl-1,3-dioxolane-4-yl)methyl (meth)acrylate. Examples of the alkyl ring (meth)acrylate include cyclic trimethylolpropane formal (meth)acrylate and the like.

As the (meth)acrylate containing a cyclic ether group, it is preferable to use either an oxetane ring-containing (meth)acrylate or a tetrahydrofuran ring-containing (meth)acrylate, and it is also preferable to use them in combination.

In addition, as the monofunctional (meth)acrylate compound, hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate, alkoxyalkyl (meth)acrylates such as 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, and 2-butoxyethyl (meth)acrylate, alkoxyethylene glycol (meth)acrylates such as methoxyethylene glycol (meth)acrylate and ethoxyethylene glycol (meth)acrylate, methoxydiglycol (meth)acrylate, methoxytriglycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethylcarbitol (meth)acrylate, ethoxydiglycol (meth)acrylate, ethoxytriglycol (meth)acrylate, ethoxypolyethylene glycol (meth)acrylate, and polyoxyethylene (meth)acrylates such as ethoxypolyethylene glycol (meth)acrylate can also be used.

As the monofunctional (meth)acrylic acid compound, a (meth)acrylic acid compound containing a carboxyl group, such as acrylic acid or methacrylic acid, can be used.

(Multifunctional radical polymerizable compound)

The light moisture curable resin composition of the present invention may contain a multifunctional free radical polymerizable compound as a free radical polymerizable compound. By containing a multifunctional free radical polymerizable compound, it is easy to make the gel fraction above a certain value, and it is easy to give a hardness above a certain value. Therefore, the shape retention becomes good after photocuring. For example, even if it is applied to one adherend with a narrow width and photocured, and other adherends are crimped, the light moisture curable resin composition is prevented from being crushed, and it is easy to maintain a narrow width state.

Examples of the polyfunctional free radical polymerizable compound include bifunctional (meth)acrylate compounds, trifunctional or higher-functional (meth)acrylate compounds, bifunctional or higher-functional urethane (meth)acrylates, etc. Among them, bifunctional or trifunctional or higher-functional (meth)acrylate compounds are preferred, and trifunctional or higher-functional (meth)acrylate compounds are more preferred from the viewpoint of increasing the gel fraction.

When the optical moisture curable resin composition contains a multifunctional free radical polymerizable compound, from the viewpoint of easily improving the shape retention of the optical moisture curable resin composition, the content of the multifunctional free radical polymerizable compound is preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass or more, and further preferably 0.5 parts by mass or more relative to 100 parts by mass of the free radical polymerizable compound. From the viewpoint of improving the shape retention, the upper limit of the content of the multifunctional free radical polymerizable compound is not particularly specified, but from the viewpoint of imparting appropriate softness to the optical moisture curable resin composition and facilitating bonding of adherends to each other, it is preferably 30 parts by mass or less, and more preferably 20 parts by mass or less.

Examples of the bifunctional (meth)acrylate compound include 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 2-n-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate. ) acrylate, polypropylene glycol di(meth)acrylate, ethylene oxide added bisphenol A di(meth)acrylate, propylene oxide added bisphenol A di(meth)acrylate, ethylene oxide added bisphenol F di(meth)acrylate, dihydroxymethyl dicyclopentadienyl di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2-hydroxy-3-(meth)acryloxypropyl (meth)acrylate, carbonate diol di(meth)acrylate, polyether diol di(meth)acrylate, polyester diol di(meth)acrylate, polycaprolactone diol di(meth)acrylate, polybutadiene diol di(meth)acrylate, etc.

Examples of the trifunctional or higher-functional (meth)acrylate compound include trimethylolpropane tri(meth)acrylate, ethylene oxide-added trimethylolpropane tri(meth)acrylate, propylene oxide-added trimethylolpropane tri(meth)acrylate, caprolactone-modified trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, glycerol tri(meth)acrylate, propylene oxide-added glycerol tri(meth)acrylate, tri(meth)acryloyloxyethyl phosphate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

As the bifunctional or higher-functional urethane (meth)acrylate, for example, one obtained by reacting a (meth)acrylic acid derivative having a hydroxyl group with an isocyanate compound can be used.

Examples of the (meth)acrylic acid derivative having a hydroxyl group include mono(meth)acrylates of diols such as ethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and polyethylene glycol; mono(meth)acrylates or di(meth)acrylates of triols such as trimethylolethane, trimethylolpropane, and glycerol; and epoxy(meth)acrylates such as bisphenol A epoxy(meth)acrylate.

Examples of the isocyanate compound used to obtain the urethane (meth)acrylate include polyisocyanate compounds such as isophorone diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,6-hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, diphenylmethane-4,4′-diisocyanate (MDI), hydrogenated MDI, polymeric MDI, 1,5-naphthalene diisocyanate, norbornane diisocyanate, dimethylbiphenyl diisocyanate, xylylene diisocyanate (XDI), hydrogenated XDI, lysine diisocyanate, triphenylmethane triisocyanate, tris(isocyanatophenyl)phosphorothioate, tetramethylxylylene diisocyanate, and 1,6,11-undecane triisocyanate.

In addition, as the isocyanate compound, a chain-extended polyisocyanate compound obtained by the reaction of a polyol with an excess of an isocyanate compound may also be used. Here, as the polyol, for example, ethylene glycol, propylene glycol, glycerol, sorbitol, trimethylolpropane, carbonate diol, polyether diol, polyester diol, polycaprolactone diol, etc. may be mentioned.

By using these polyisocyanate compounds, polyfunctional urethane (meth)acrylate can be obtained.

＜Moisture curing resin＞

Examples of the moisture-curable resin used in the present invention include moisture-curable urethane resins, hydrolyzable silyl group-containing resins, and moisture-curable cyanoacrylate resins. Among them, any one of moisture-curable urethane resins and hydrolyzable silyl group-containing resins is preferred, and moisture-curable urethane resins are more preferred. These may be used alone or in combination of two or more.

(Moisture curable urethane resin)

Moisture-curable urethane resin can be obtained by reacting a polyol compound having two or more hydroxyl groups in one molecule with a polyisocyanate compound having two or more isocyanate groups in one molecule. It is preferred that the moisture-curable urethane resin has an isocyanate group in the molecule, and the isocyanate group in the molecule reacts with moisture in the air or in the adherend to cure. The moisture-curable urethane resin may have only one isocyanate group in one molecule, or may have two or more, but the moisture-curable urethane resin preferably has one or two isocyanate groups in one molecule. In addition, the isocyanate group is not particularly limited, but it is preferably provided at the end of the moisture-curable urethane resin.

The reaction of the polyol compound and the polyisocyanate compound is usually carried out in a range of [NCO]/[OH]=2.0 to 2.5 in terms of the molar ratio of the hydroxyl group (OH) in the polyol compound to the isocyanate group (NCO) in the polyisocyanate compound.

As the polyol compound that becomes the raw material of moisture-curable urethane resin, the well-known polyol compound commonly used in the manufacture of polyurethane can be used, for example, polyester polyol, polyether polyol, polyalkylene polyol, polycarbonate polyol, etc. These polyol compounds can be used alone or in combination of two or more.

The moisture-curable urethane resin is preferably at least any one of the moisture-curable urethane resins having a polycarbonate skeleton, a polyether skeleton, or a polyester skeleton, more preferably at least any one of the moisture-curable urethane resins having a polycarbonate skeleton or a polyether skeleton, and further preferably a moisture-curable urethane resin having a polycarbonate skeleton. The moisture-curable urethane resin has excellent adhesive force by having a polycarbonate skeleton. Furthermore, it is also possible to provide an optical moisture-curable resin composition having excellent weather resistance, heat resistance, moisture resistance, etc. of the cured product.

(Moisture-curable urethane resin having a polycarbonate skeleton)

The moisture-curable urethane resin having a polycarbonate skeleton is a material obtained by introducing a polycarbonate skeleton into a urethane resin by using a polycarbonate polyol as the polyol compound. The moisture-curable urethane resin having a polycarbonate skeleton can be obtained, for example, by reacting a polycarbonate polyol having two or more hydroxyl groups in one molecule with a polyisocyanate compound having two or more isocyanate groups in one molecule.

As the polycarbonate polyol, polycarbonate diol is preferred, and specific preferred examples of the polycarbonate diol include compounds represented by the following formula (1).

In the formula (1), R is a divalent hydrocarbon group having 4 to 16 carbon atoms, and n is an integer of 2 to 500.

In formula (1), R is preferably an aliphatic saturated hydrocarbon group. R is an aliphatic saturated hydrocarbon group, so that heat resistance is easy to become good. In addition, it is not easy to yellow due to thermal degradation, etc., and weather resistance is also good. R consisting of an aliphatic saturated hydrocarbon group can have a chain structure or a cyclic structure, but from the viewpoint of being easy to make stress relaxation and flexibility good, it is preferably a chain structure. In addition, the chain structure R can be any one of a straight chain and a branched chain.

n is preferably 5-200, more preferably 10-150, further preferably 20-50.

The R contained in the polycarbonate polyol constituting the moisture-curable urethane resin may be used alone or in combination of two or more. When two or more are used in combination, at least a portion of them is preferably a chain aliphatic saturated hydrocarbon group having 6 or more carbon atoms.

By including a chain aliphatic saturated hydrocarbon group having 6 or more carbon atoms, stress relaxation and flexibility can be easily improved. When the polycarbonate diol is a compound represented by the above formula (1), the proportion of the chain aliphatic saturated hydrocarbon group having 6 or more carbon atoms is preferably 20 mol% to 100 mol% with respect to R contained in the whole polycarbonate diol, more preferably 30 mol% to 100 mol% and further preferably 50 mol% to 100 mol%.

The chain aliphatic saturated hydrocarbon group having 6 or more carbon atoms preferably has 6 or more and 12 or less carbon atoms, and more preferably has 6 or more and 10 or less carbon atoms.

As a specific example of R, it can be a straight chain such as 1,4-butylene, pentylene, 1,6-hexylene, 1,7-heptylene, 1,8-octylene, 1,9-nonylene, 1,10-decylene, etc., or a branched chain such as methylpentylene such as 3-methylpentylene, methyl 1,8-octylene, etc. Multiple Rs in one molecule may be the same or different. Therefore, two or more Rs may be contained in one molecule, in which case, it is preferred that two or three Rs are contained in one molecule. For example, a polycarbonate polyol may be a copolymer containing R with a carbon number of 6 or less and R with a carbon number of 7 or more in one molecule, in which case, it is preferred that any R is a chain-like aliphatic saturated hydrocarbon group.

Furthermore, R may contain a linear aliphatic saturated hydrocarbon group or a branched aliphatic saturated hydrocarbon group. R in the polycarbonate polyol may contain a branched and a linear R in combination, or a linear R alone may be used.

In addition, the polycarbonate polyol may be used individually by 1 type, or may use 2 or more types together.

As the polyisocyanate compound serving as a raw material of the moisture-curable urethane resin, an aromatic polyisocyanate compound or an aliphatic polyisocyanate compound is preferably used.

Examples of the aromatic polyisocyanate compound include diphenylmethane diisocyanate, liquid modified products of diphenylmethane diisocyanate, polymeric MDI, toluene diisocyanate, and naphthalene-1,5-diisocyanate.

Examples of the aliphatic polyisocyanate compound include hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, norbornane diisocyanate, trans-cyclohexane-1,4-diisocyanate, isophorone diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate, cyclohexane diisocyanate, bis(isocyanatomethyl)cyclohexane, and dicyclohexylmethane diisocyanate.

As the polyisocyanate compound, aromatic polyisocyanate compounds are preferred from the viewpoint of being able to increase the adhesive force after complete curing, and diphenylmethane diisocyanate and its modified products are more preferred. In addition, aliphatic polyisocyanate compounds are preferred from the viewpoint of being easy to impart stress relaxation, flexibility, etc. to the cured product of the light moisture curable resin composition.

The polyisocyanate compound may be used alone or in combination of two or more.

(Moisture-curable urethane resin having a polyester skeleton)

The moisture-curable urethane resin having a polyester skeleton is a material obtained by introducing a polyester skeleton into the urethane resin by using a polyester polyol as the polyol compound. The moisture-curable urethane resin having a polyester skeleton can be obtained by reacting a polyester polyol having two or more hydroxyl groups in one molecule with a polyisocyanate compound having two or more isocyanate groups in one molecule.

Examples of the polyester polyol include polyester polyols obtained by reaction of polycarboxylic acid and polyol, and poly-ε-caprolactone polyols obtained by ring-opening polymerization of ε-caprolactone.

Examples of the polycarboxylic acid used as the raw material of the polyester polyol include phthalic acid, terephthalic acid, isophthalic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, sebacic acid, dodecanedicarboxylic acid, etc. Among them, phthalic acid or adipic acid is preferred from the viewpoint of being easier to improve the adhesive force at high temperature.

Examples of the polyols used as the raw materials of the polyester polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, diethylene glycol, cyclohexanediol, etc. Among them, 1,6-hexanediol or 1,4-butanediol is preferred from the viewpoint of being easier to improve the adhesive force at high temperatures.

In addition, the polyester polyol may be used individually by 1 type, or may use 2 or more types together.

(Moisture-curable urethane resin having a polyether skeleton)

The moisture-curable urethane resin having a polyether skeleton is a material obtained by introducing a polyether skeleton into the urethane resin by using a polyether polyol as the polyol compound. The urethane resin having a polyether skeleton can be obtained by reacting a polyether polyol having two or more hydroxyl groups in one molecule with a polyisocyanate compound having two or more isocyanate groups in one molecule.

Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, ring-opening polymers of tetrahydrofuran, ring-opening polymers of 3-methyltetrahydrofuran, random copolymers or block copolymers of these or their derivatives, and bisphenol-type polyoxyalkylene modified products. Among these, polypropylene glycol, ring-opening polymers of tetrahydrofuran, or ring-opening polymers of 3-methyltetrahydrofuran are preferred from the viewpoint of easily improving the coating properties of the optical moisture curable resin composition.

Here, the bisphenol-type polyoxyalkylene modified body is a polyether polyol obtained by adding an oxyalkylene (e.g., ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, etc.) to the active hydrogen part of the bisphenol-type molecular skeleton. The polyether polyol may be a random copolymer or a block copolymer. The bisphenol-type polyoxyalkylene modified body preferably has one or more oxyalkylenes added to both ends of the bisphenol-type molecular skeleton.

The bisphenol type is not particularly limited, and examples thereof include A type, F type, and S type, and bisphenol A type is preferred.

Moreover, as the polyisocyanate compound, the above-mentioned polyisocyanate compounds can be used.

The moisture-curable urethane resin having a polyether skeleton preferably further comprises a substance obtained by using a polyol compound having a structure represented by the following formula (2). By using a polyol compound having a structure represented by the following formula (2), an optical moisture-curable resin composition having excellent adhesion and a cured product having softness and good elongation can be obtained, and the compatibility with free radical polymerizable compounds is excellent.

Among them, polypropylene glycol, a ring-opening polymer compound of a tetrahydrofuran (THF) compound, or a polyether polyol formed by a ring-opening polymer compound of a tetrahydrofuran compound having a substituent such as a methyl group is preferred, and a ring-opening polymer compound of polypropylene glycol and a tetrahydrofuran (THF) compound is more preferred. The ring-opening polymer compound of a tetrahydrofuran (THF) compound is generally polytetramethylene ether glycol.

In addition, the polyether polyol may be used individually by 1 type, or may use 2 or more types together.

In formula (2), R represents a hydrogen atom, a methyl group, or an ethyl group, l is an integer of 0 to 5, m is an integer of 1 to 500, and n is an integer of 1 to 10. l is preferably 0 to 4, m is preferably 50 to 200, and n is preferably 1 to 5. It should be noted that the case where l is 0 refers to the case where the carbon bonded to R is directly bonded to oxygen.

In the above, the total of n and l is more preferably 1 or more, and further preferably 1 to 3. Furthermore, R is more preferably a hydrogen atom or a methyl group, and particularly preferably a methyl group.

The above-mentioned moisture-curable urethane resin with polycarbonate, polyester or polyether skeleton can have two or more skeletons in the molecule, for example, can have a polycarbonate skeleton and a polyester skeleton. In this case, it is good to use polycarbonate polyol and polyester polyol as the above-mentioned polyol compound becoming raw materials. Similarly, moisture-curable urethane resin with a polyester skeleton and a polyether skeleton etc. can also be used.

As described above, the moisture-curable urethane resin preferably contains an isocyanate group, but is not limited to the isocyanate group-containing urethane resin, and may be a urethane resin containing a hydrolyzable silyl group.

The hydrolyzable silyl group is represented by, for example, the following formula (3).

-SiR ¹ _3-a X _a (3)

In formula (3), ^R1 is independently an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a _{triorganosiloxy} group represented by ^-OSiR23 ( ^R2 is independently a hydrocarbon group having 1 to 20 carbon atoms). In addition, in formula (3), X is independently a hydroxyl group or a hydrolyzable group. Furthermore, in formula (3), a is an integer of 1 to 3.

The hydrolyzable group is not particularly limited, and for example, halogen atoms, alkoxy groups, alkenyloxy groups, aryloxy groups, acyloxy groups, ketoxime ester groups, amino groups, amide groups, acid amide groups, aminooxy groups, sulfhydryl groups, etc. can be cited. Among them, halogen atoms, alkoxy groups, alkenyloxy groups, and acyloxy groups are preferred from the perspective of high activity. In addition, alkoxy groups such as methoxy groups and ethoxy groups are more preferred from the perspective of stable hydrolysis and easy operation, and methoxy groups and ethoxy groups are further preferred. In addition, from the perspective of safety, the compounds that are preferably separated by the reaction are ethanol, acetone, ethoxy, and isopropyleneoxy groups, respectively.

The number of the hydroxyl group or the hydrolyzable group bonded to one silicon atom may be 1 to 3. When two or more hydroxyl groups or the hydrolyzable groups bond to one silicon atom, these groups may be the same or different.

From the viewpoint of curability, a in the formula (3) is preferably 2 or 3, and particularly preferably 3. Furthermore, from the viewpoint of storage stability, a is preferably 2.

In the above formula (3), R ¹ includes, for example, methyl, alkyl such as ethyl, cycloalkyl such as cyclohexyl, aryl such as phenyl, aralkyl such as benzyl, trimethylsilyloxy, chloromethyl, methoxymethyl, etc. Among them, methyl is preferred.

Examples of the hydrolyzable silyl group include methyldimethoxysilyl, trimethoxysilyl, triethoxysilyl, tri(2-propenyloxy)silyl, triacetoxysilyl, (chloromethyl)dimethoxysilyl, (chloromethyl)diethoxysilyl, (dichloromethyl)dimethoxysilyl, (1-chloroethyl)dimethoxysilyl, (1-chloropropyl)dimethoxysilyl, (methoxymethyl)dimethoxysilyl, and (methoxymethyl)diethoxysilyl. dimethoxysilyl, (ethoxymethyl)dimethoxysilyl, (1-methoxyethyl)dimethoxysilyl, (aminomethyl)dimethoxysilyl, (N,N-dimethylaminomethyl)dimethoxysilyl, (N,N-diethylaminomethyl)dimethoxysilyl, (N,N-diethylaminomethyl)diethoxysilyl, (N-(2-aminoethyl)aminomethyl)dimethoxysilyl, (acetoxymethyl)dimethoxysilyl, (acetoxymethyl)diethoxysilyl and the like.

As a method for producing the polyurethane resin containing a hydrolyzable silyl group, for example, when a polyol compound and a polyisocyanate compound are reacted to produce a polyurethane resin, a method of further reacting a compound containing a silyl group such as a silane coupling agent, etc. Specifically, for example, a method for synthesizing a carbamate oligomer having a hydrolyzable silyl group described in Japanese Patent Application Laid-Open No. 2017-48345, etc. can be mentioned.

Examples of the silane coupling agent include vinyl trichlorosilane, vinyl triethoxysilane, vinyl tri(β-methoxy-ethoxy)silane, β-(3,4-epoxycyclohexyl)-ethyl trimethoxysilane, γ-glycidoxypropyl trimethoxysilane, γ-glycidoxypropyl methyl diethoxysilane, γ-methacryloxypropyl trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyl trimethyl dimethoxysilane, N-phenyl-γ-aminopropyl trimethoxysilane, γ-chloropropyl trimethoxysilane, γ-mercaptopropyl trimethoxysilane, γ-aminopropyl trimethoxysilane, 3-isocyanate propyl trimethoxysilane, and 3-isocyanate propyl triethoxysilane. Among them, γ-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltrimethoxysilane, and 3-isocyanatepropyltriethoxysilane are preferred. These silane coupling agents may be used alone or in combination of two or more.

In addition, the moisture-curable urethane resin may have both an isocyanate group and a hydrolyzable silyl group. The moisture-curable urethane resin having both an isocyanate group and a hydrolyzable silyl group is preferably produced by first obtaining a moisture-curable urethane resin having an isocyanate group (raw material urethane resin) by the above method, and further reacting a silane coupling agent with the raw material urethane resin.

It should be noted that the details of the moisture-curable urethane resin with isocyanate group are as described above. As the silane coupling agent reacted with the raw material urethane resin, it is not particularly limited, as long as it is appropriately selected from the above-mentioned materials and used, but from the viewpoint of the reactivity with isocyanate group, it is preferred to use a silane coupling agent with amino or mercapto. As preferred specific examples, N-(β-aminoethyl)-γ-aminopropyl trimethoxysilane, N-(β-aminoethyl)-γ-aminopropyl trimethyl dimethoxysilane, N-phenyl-γ-aminopropyl trimethoxysilane, γ-mercaptopropyl trimethoxysilane, γ-aminopropyl trimethoxysilane, 3-isocyanate propyl trimethoxysilane, etc. can be cited.

Furthermore, the moisture-curable resin may have a free radical polymerizable functional group. As the free radical polymerizable functional group that the moisture-curable urethane resin may have, a group having an unsaturated double bond is preferred, and in particular, a (meth)acryloyl group is more preferred from the aspect of reactivity. It should be noted that the moisture-curable resin having a free radical polymerizable functional group is not included in the above-mentioned free radical polymerizable compound and is treated as a moisture-curable resin.

The moisture-curable resin may be appropriately selected from the above-mentioned various resins and used alone or in combination of two or more.

The weight average molecular weight of the moisture-curable resin is preferably 7500 or more and 30000 or less. By making the weight average molecular weight within the above range, it is easy to make the internal and external ratio a/b and the viscosity at 25°C of the optical moisture-curable resin composition described later within the specified range, so that the adhesive force is high. In addition, by being below the above upper limit, it is also easy to make the final adhesive force good. From these viewpoints, the weight average molecular weight of the moisture-curable resin is more preferably 7800 or more, more preferably 10000 or more, and more preferably 11500 or more. In addition, it is more preferably 24000 or less, more preferably 20000 or less, and more preferably 16000 or less.

In addition, in this specification, the said weight average molecular weight is the value calculated|required by polystyrene conversion by gel permeation chromatography (GPC).

The moisture-curable resin may be chain-extended in order to adjust the weight average molecular weight to a certain value or more as described above.

For example, in a moisture-curable urethane resin, a urethane resin having an isocyanate group (hereinafter, also referred to as a "raw urethane resin") obtained by reacting a polyol compound with a polyisocyanate compound having two or more isocyanate groups in one molecule can be further reacted with a chain extender to obtain a moisture-curable urethane resin. At this time, regarding the chain extender, it is better to adjust the amount of the chain extender used without reacting the chain extender with all the isocyanate groups of the raw urethane resin so that the isocyanate groups remain in the moisture-curable urethane resin. In addition, the chain extender that has reacted with the raw urethane resin can be further reacted with the raw urethane resin.

The chain extender used in the moisture curable urethane resin is preferably a polyol compound. The details of the polyol compound are as described above. In addition, the polyol compound used as the chain extender can be a polyol compound of the same type as the polyol compound used to synthesize the raw material urethane resin. Therefore, if the polyol compound used to synthesize the raw material urethane resin is a polycarbonate polyol, the chain extender can also be a polycarbonate polyol.

The amount of the chain extender used is, for example, 5 to 40 parts by mass, preferably 10 to 35 parts by mass, and more preferably 15 to 30 parts by mass, based on 100 parts by mass of the total amount of the raw material urethane resin and the chain extender.

In the optical moisture curable resin composition, the mass ratio of the moisture curable resin to the free radical polymerizable compound is preferably 30/70 or more and 90/10 or less, more preferably 40/60 or more and 80/20 or less, and further preferably 50/50 or more and 70/30 or less. When the mass ratio is within these ranges, the optical moisture curable resin composition can be imparted with light curing properties and moisture curing properties in a well-balanced manner, and the adhesive strength can be easily adjusted within a desired range.

The total content of the radical polymerizable compound and the moisture curable resin in the optical moisture curable resin composition is not particularly limited, but is, for example, 50% by mass or more, preferably 60% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more, based on the total amount of the optical moisture curable resin composition. By making their total amount above the above lower limit, it is easy to impart appropriate light curing properties and moisture curing properties to the moisture curable resin composition. In addition, the above total content can be less than 100% by mass, but in order to appropriately contain other components, it is preferably 99% by mass or less, and more preferably 98% by mass or less.

The optical moisture curable resin composition may contain resin components other than free radical polymerizable compounds and moisture curable resins as resin components, and may contain resin components such as non-curable thermoplastic resins (for example, acrylic resins, urethane resins, etc.), thermosetting resins, etc., within the range not impairing the effects of the present invention.

The proportion of the resin components other than the radical polymerizable compound and the moisture curable resin is, for example, 50 parts by mass or less, preferably 30 parts by mass or less, and more preferably 10 parts by mass or less, based on 100 parts by mass of the total amount of the radical polymerizable compound and the moisture curable resin.

＜Photoradical polymerization initiator＞

The optical moisture curable resin composition of the present invention contains a photoradical polymerization initiator. The optical moisture curable resin composition is appropriately provided with photocurability by containing a photoradical polymerization initiator.

Examples of the photoradical polymerization initiator include benzophenone compounds, acetophenone compounds, alkylphenone photoradical polymerization initiators, acylphosphine oxide compounds, titanocene compounds, oxime ester compounds, benzoin ether compounds, and thioxanthone.

As commercially available substances among the above-mentioned photoradical polymerization initiators, for example, IRGACURE184, IRGACURE369, IRGACURE379, IRGACURE379EG, IRGACURE651, IRGACURE784, IRGACURE819, IRGACURE907, IRGACURE2959, IRGACURE OXE01, IRGACURE TPO (all manufactured by BASF), benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether (all manufactured by Tokyo Chemical Industry Co., Ltd.), Omnirad 819, Omnirad TPOH (all manufactured by IGM Resins B.V.), etc.

As the above-mentioned photoradical polymerization initiator, an acylphosphine oxide compound is preferred. As the acylphosphine oxide compound, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, etc. can be mentioned, among which bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide is more preferred.

The content of the photo-radical polymerization initiator in the light moisture curable resin composition is preferably 0.1 parts by mass or more and 10 parts by mass or less, and more preferably 0.5 parts by mass or more and 5 parts by mass or less, relative to 100 parts by mass of the radical polymerizable compound. When the content of the photo-radical polymerization initiator is within these ranges, the photocurability and storage stability of the obtained light moisture curable resin composition are excellent. In addition, when it is within the above range, the photo-radical polymerizable compound is appropriately cured, and it is easy to make the adhesive force good.

＜Filling agent＞

The optical moisture curable resin composition of the present invention preferably contains a filler. By containing a filler, the optical moisture curable resin composition of the present invention has suitable thixotropy and can fully maintain the shape after coating. As the filler, a particulate material can be used.

As the filler, an inorganic filler is preferred, and examples thereof include silicon dioxide, talc, titanium oxide, zinc oxide, calcium carbonate, etc. Among them, silicon dioxide is preferred because the obtained optical moisture curing resin composition has excellent ultraviolet transmittance. In addition, the filler may be subjected to a hydrophobic surface treatment such as silylation, alkylation, epoxidation, etc.

The filler may be used alone or in combination of two or more.

The content of the filler is preferably 1 part by mass or more and 25 parts by mass or less, more preferably 2 parts by mass or more and 20 parts by mass or less, and further preferably 3 parts by mass or more and 15 parts by mass or less, relative to 100 parts by mass of the total amount of the radical polymerizable compound and the moisture curable resin.

The optical moisture curable resin composition of the present invention may contain colorants other than zirconium nitride, moisture curing accelerators, coupling agents, wax particles, ionic liquids, foamed particles, expanded particles, reactive diluents and other additives in addition to the above-described components, as long as the effects of the present invention are not impaired. It should be noted that, as colorants other than zirconium nitride, iron oxide, titanium black, aniline black, cyanine black, fullerene, carbon black, resin-coated carbon black, etc. can be cited. In addition, as coupling agents, silane coupling agents, titanate coupling agents, zirconate coupling agents, etc. can be cited.

The optical moisture curable resin composition may be diluted with a solvent as needed. When the optical moisture curable resin composition is diluted with a solvent, the amount of the optical moisture curable resin composition described above is based on the solid content, that is, refers to the mass excluding the solvent.

As a method for producing the optical moisture curable resin composition of the present invention, there can be mentioned a method of mixing a radical polymerizable compound, a moisture curable resin, a photo radical polymerization initiator, and zirconium nitride, and other additives such as a filler, a moisture curing accelerator, and a colorant as required using a mixer, etc. Examples of the mixer include a homodispersor, a homomixer, a universal mixer, a planetary mixer (planetary stirring device), a kneader, and a three-roller.

In addition, as described above, the moisture-curable urethane resin may be made to have a large molecular weight by using a chain extender. In this case, for example, a raw material resin such as a raw urethane resin is reacted with a chain extender in advance to obtain a moisture-curable urethane resin, and then, as described above, it is preferable to mix it with other raw materials such as a radical polymerizable compound.

In addition, the chain extender and the raw resin are reacted to synthesize a moisture-curable resin by mixing the raw resin, the chain extender, and the radical polymerizable compound, and heating the mixture as needed. In this case, since a mixture of the moisture-curable resin and the radical polymerizable compound is obtained, a photo-radical polymerization initiator and other additives may be added to the mixture as needed to obtain a light moisture-curable resin composition.

＜Inside-outside ratio a/b＞

The moisture-curable resin composition of the present invention preferably has an internal-external ratio a/b of 0.5 or more and 0.95 or less. If the internal-external ratio a/b is 0.5 or more, it is not easy to be crushed just after photocuring, and it is easy to make the initial adhesive force good even if the moisture-curable resin composition is blackened. In addition, if the internal-external ratio a/b is 0.95 or less, it will not be excessively crushed just after photocuring, and it is not easy to peel off from the adherend, and it can prevent the reduction of adhesive force even if the moisture-curable resin composition is blackened.

The above-mentioned inside-outside ratio a/b is preferably 0.54 or more, more preferably 0.58 or more, and further preferably 0.60 or more, and is preferably 0.92 or less, more preferably 0.89 or less, and further preferably 0.87 or less. If the inside-outside ratio a/b is within the above range, it is easy to make the initial adhesive force good.

In the present invention, the inside-outside ratio a/b is measured as follows. First, as shown in FIG. 1(a), a moisture-curable resin composition 10 is applied to an aluminum substrate 11 with a line width of 1.0 mm. Here, the so-called line width of 1.0 mm does not need to be strictly 1.0 mm, and may have an error of 1.0 ± 0.1 mm. Next, as shown in FIG. 1(b), the moisture-curable resin composition 10 is irradiated with ultraviolet rays of 1500 mJ/ ^cm2 to cure the moisture-curable resin composition 10. Then, immediately (within 10 seconds), as shown in FIG. 1(c), a glass plate 12 is overlapped on the moisture-curable resin composition 10, and the glass plate 12 is crimped to the moisture-curable resin composition 10 at 0.08 MPa for 120 seconds. After crimping, the width a1 of the bonding portion between the moisture-curable resin composition 10 and the glass plate 12 is measured. Regarding the width a1, 5 points are measured, and the average value thereof is set as the average width a. The width b1 of the bonded portion between the moisture-curable resin composition 10 and the aluminum substrate 11 was measured. The width b1 was measured at five points, and the average value was defined as the average width b. The inside-outside ratio a/b was calculated from the average widths a and b.

The internal-external ratio a/b can be adjusted to the above range by adjusting the type of free radical polymerizable compound, etc. For example, in the case where the light moisture curable resin composition contains a monofunctional free radical polymerizable compound as a free radical polymerizable compound, the ratio of the internal-external ratio a/b can be made larger because the proportion of the cross-linked structure formed after photocuring becomes smaller. In addition, for example, in the case where the light moisture curable resin composition contains a free radical polymerizable compound with a low glass transition temperature of the homopolymer as a free radical polymerizable compound, the cured product after photocuring becomes soft, so the ratio of the internal-external ratio a/b can be made larger. Furthermore, it can also be adjusted by the weight average molecular weight of the moisture curable urethane resin.

＜Viscosity at 25℃＞

The optical moisture curing resin composition of the present invention preferably has a viscosity (hereinafter referred to as "25°C viscosity") measured at 25°C and 5.0 rpm using a cone-plate viscometer of 40 Pa·s or more and 600 Pa·s or less. If the 25°C viscosity is 40 Pa·s or more, since the low molecular weight components contained in the moisture curing resin, etc. are reduced, the moisture curing resin, etc. are prevented from seeping out to the interface after light irradiation, and the initial adhesion is easily improved even when the optical moisture curing resin composition is blackened. That is, by preventing the low molecular weight moisture curing resin, etc. from seeping out to the interface after light irradiation, it is not easy to slide between the adherend, and it is easy to show adhesion, so that the initial adhesion is easily improved. In addition, if the above-mentioned 25°C viscosity is less than 600 Pa·s, the adhesion inherent to the moisture curing resin is easy to show, thereby, even when the optical moisture curing resin composition is blackened, the initial adhesion and the final adhesion can be improved.

The 25°C viscosity of the light moisture curing resin composition is more preferably 45 Pa·s or more, further preferably 90 Pa·s or more, further preferably 110 Pa·s or more, and preferably 500 Pa·s or less, more preferably 350 Pa·s or less, and further preferably 230 Pa·s or less. If the 25°C viscosity is within the above range, it is easy to improve the workability and initial adhesion. In addition, if it is below the above upper limit, the molecular weight of the moisture curing urethane resin can be prevented from being excessively high, so the adhesion is sufficiently increased by moisture curing, and it is also easy to improve the final adhesion, etc. It should be noted that the so-called final adhesion refers to the adhesion of the light moisture curing resin composition after light curing and moisture curing.

From the viewpoint of obtaining good initial adhesive force, the optical moisture curable resin composition of the present invention preferably has both an internal/external ratio a/b and a 25° C. viscosity within the above numerical ranges.

＜Initial shear force＞

The initial shear force of the optical moisture curing type resin composition of the present invention is preferably more than 0.2MPa, more preferably more than 0.25MPa, and further preferably more than 0.3MPa. If the initial shear force is made to be above the above lower limit, even when the optical moisture curing type resin composition of the present invention is blackened, excellent bonding strength can be given. In addition, adherends can be temporarily bonded to each other with higher bonding strength immediately after light curing, and the workability during temporary bonding is improved. On the other hand, the upper limit of the initial shear force is not particularly limited, but from a practical point of view, for example, less than 10.0MPa.

In addition, the initial shear force refers to the shear force at 25° C. immediately after the optical moisture curable resin composition is photocured. The details of the method for measuring the initial shear force are described in the examples described later.

＜Initial creep force＞

In the optical moisture curable resin composition of the present invention, the initial creep force can be expressed by the distance h by which the glass plate deviates from the polycarbonate substrate in 1 hour when the obtained evaluation sample is vertically erected after coating the optical moisture curable resin composition on a polycarbonate substrate and photocuring the polycarbonate substrate, then laminating a glass plate via the optical moisture curable resin composition.

A short distance h means a high initial creep force, and specifically, it is preferably 0.15 mm or less, and more preferably 0.10 mm or less.

By making the initial creep force below the upper limit, the initial bonding force becomes high, for example, even when a heavy substance is temporarily bonded and placed upright for moisture curing, the adherend can be prevented from deviating. The lower the distance h, the better, and it can be 0 mm or more.

In addition, the initial creep force refers to the creep force at 25° C. immediately after the optical moisture curable resin composition is photocured, and the details of the method for measuring the distance h are described in the examples described later.

＜Gel fraction＞

From the viewpoint of making the shape retention good, the gel fraction after photocuring of the light moisture curable resin composition of the present invention is preferably 10% or more, more preferably 12% or more, and further preferably 15% or more. If the gel fraction is above the above lower limit, a certain hardness is given to the light moisture curable resin composition. Therefore, the shape retention after photocuring becomes good, and even if, for example, it is applied to an adherend in a narrow width and photocured, other adherends are crimped, the light moisture curable resin composition is prevented from being crushed and maintained in a narrow width state. From the viewpoint of making the shape retention good, the upper limit of the above gel fraction after photocuring is not particularly limited, but is preferably 60% or less, more preferably 50% or less, and further preferably 40% or less. By having a gel fraction below the above upper limit, the light moisture curable resin composition is given moderate softness, and it is easy to bond adherends to each other.

On the other hand, from the viewpoint of improving the initial adhesive force, the gel fraction of the optical moisture curable resin composition of the present invention after photocuring is preferably less than 10%, more preferably 5% or less, and further preferably 1% or less. If the gel fraction is below the above upper limit, the initial adhesive force can be improved because the bonding area can be large when other adherends are pressed after photocuring. From the viewpoint of improving the initial adhesive force, the lower limit of the gel fraction after photocuring is not particularly limited as long as it is 0% or more.

In addition, the gel fraction after photocuring can be obtained by the following procedure.

(1) About 1.0 g of the optical moisture curable resin composition is taken and weighed to obtain a sample weight (W1).

(2) The coating was applied on a glass plate to a thickness of 1.0 mm and irradiated with ultraviolet light at 1500 mJ/cm ² to cure the coating, thereby preparing a sample for analysis.

(3) The analytical sample prepared above was immersed in THF at 25° C. for 48 hours.

(4) The light-cured optical moisture-curable resin composition after immersion is taken out onto a 200-mesh metal mesh and washed five times with new THF. The swollen gel remaining on the metal mesh is dried at 100°C for 2 hours to volatilize the THF. The weight of the dried gel (W2) is weighed and the gel fraction is determined by the following formula.

Gel fraction (%) = W2/W1×100

<Method of using the optical moisture curable resin composition>

The optical moisture curable resin composition of the present invention is cured and used as a cured product. Specifically, the optical moisture curable resin composition of the present invention is first photocured by light irradiation to, for example, a B-stage state (semi-cured state), and then cured by moisture to be completely cured.

Here, when the optical moisture curable resin composition is arranged between adherends and the adherends are bonded, it is applied to one adherend and then photocured by light irradiation to, for example, a B-stage state, and another adherend is overlapped on the optical moisture curable resin composition in the photocured state to temporarily bond the adherends with a moderate adhesive force (initial adhesive force). Then, the optical moisture curable resin composition in the B-stage state is cured by passing moisture through the moisture curable urethane resin, thereby being completely cured, and the overlapped adherends are formally bonded via the optical moisture curable resin composition and bonded with a sufficient adhesive force (final adhesive force).

The application of the optical moisture curable resin composition to the adherend is preferably carried out by, for example, a dispenser, but is not particularly limited. The light irradiated during photocuring is not particularly limited as long as it is light for curing the free radical polymerizable compound, but ultraviolet rays are preferred. Although the optical moisture curable resin composition of the present invention has a high OD value and high light shielding properties, it has a relatively high transmittance to ultraviolet rays, so if ultraviolet rays are used, it can be cured with high curability. In addition, when the optical moisture curable resin composition is completely cured by moisture after photocuring, it only needs to be left in the atmosphere for a specified time.

The application of the optical moisture curable resin composition to the adherend is not particularly limited, but is preferably carried out at around room temperature, specifically, at a temperature of about 10 to 35° C. If the optical moisture curable resin composition of the present invention has a viscosity at 25° C. in the above-specified range, it can be applied more easily even at around room temperature, and liquid dripping does not occur.

Furthermore, since the optical moisture curable resin composition of the present invention exhibits an initial adhesive force of a certain value or more immediately after light irradiation, temporary bonding can be performed immediately after photocuring, and workability becomes good.

The optical moisture curable resin composition of the present invention is preferably used as an adhesive for electronic components. That is, the present invention also provides an adhesive for electronic components made from the optical moisture curable resin composition.

Therefore, the adherend is preferably various electronic components constituting electronic devices. Examples of the various electronic components constituting electronic devices include various electronic components provided in display elements, substrates on which electronic components are mounted, semiconductor chips, and the like.

The material of the adherend may be any of metal, glass, plastic, etc. The shape of the adherend is not particularly limited, and examples thereof include film, sheet, plate, panel, disk, rod (rod-like body), box, and shell.

As described above, the optical moisture curable resin composition of the present invention is preferably used to join electronic components constituting electronic equipment. In addition, the optical moisture curable resin composition of the present invention is also preferably used to join electronic components to other components. Through these structures, the electronic component has the cured body of the present invention.

In addition, the optical moisture curable resin composition of the present invention is used for obtaining an assembly component by bonding substrates to substrates in the interior of an electronic device, etc. The assembly component obtained by such operation comprises a first substrate, a second substrate, and a cured product of the present invention, and at least a portion of the first substrate and at least a portion of the second substrate are bonded via the cured product. It should be noted that the first substrate and the second substrate are preferably each mounted with at least one electronic component.

Furthermore, the optical moisture curable resin composition of the present invention is preferably used for display element applications. That is, the present invention also provides an adhesive for display elements made of the optical moisture curable resin composition.

The optical moisture curable resin composition of the present invention can prevent light leakage due to its high light-shielding property, so by using the composition in display element applications, a high contrast ratio can be obtained. In the case of using the optical moisture curable resin composition of the present invention in display element applications, for example, for various display element devices, an adhesive is applied to the base of a narrow-width quadrilateral frame (i.e., a narrow frame), and a display panel, a touch panel, etc. are assembled via the adhesive. As the adhesive, it is better to use the optical moisture curable resin composition of the present invention. Furthermore, the optical moisture curable resin composition of the present invention can be used in semiconductor chip applications. For the use of semiconductor chips, the optical moisture curable resin composition of the present invention is used, for example, to bond semiconductor chips to each other.

Example

Hereinafter, the present invention will be described in further detail using Examples, but the present invention is not limited to these Examples.

[Physical properties]

In each of the Examples and Comparative Examples, the physical properties of the optical moisture curable resin composition were evaluated as follows.

＜Weight average molecular weight＞

The weight average molecular weight of the moisture-curable resin in each embodiment and comparative example was measured by gel permeation chromatography (GPC) and obtained by polystyrene conversion. Shodex KF-806L (Showa Denko Co., Ltd.) was used as a column for GPC measurement. In addition, tetrahydrofuran (THF) was used as a solvent and mobile phase. Further, as the measurement conditions of GPC, a flow rate of 1.0 ml/min and a measurement temperature of 40°C were used.

It should be noted that in each embodiment and comparative example, the weight average molecular weight is measured using a mixture of a radical polymerizable compound and a moisture curable resin as a sample. For this mixture, since a peak of the radical polymerizable compound appears on the low molecular weight side and a peak of the moisture curable resin appears on the high molecular weight side, the weight average molecular weight of the moisture curable resin can be obtained from the peak on the high molecular weight side.

＜OD value＞

Each optical moisture curable resin composition obtained in the examples and comparative examples was uniformly applied to a slide glass ("S1214", manufactured by Matsunami Glass Industries, Ltd.) in a thickness of 1 mm, and then irradiated with ultraviolet rays of a wavelength of 365 nm at 1500 mJ/ ^cm2 using a UV-LED irradiator (manufactured by Seashells Co., Ltd.), thereby photocuring the optical moisture curable resin composition to obtain a sample for light shielding property evaluation.

The OD value of the obtained sample for evaluating light-shielding properties was measured using a densitometer (manufactured by X-rite, “spectrometer”).

It should be noted that when measuring the OD value, the illumination during photocuring was adjusted within the range of 500 to 3000 mW/cm ^2. The same applies to the measurement of the gel fraction, initial shear force, initial creep force, and internal/external ratio [a/b] described below.

＜Viscosity at 25℃＞

The 25°C viscosity was measured under the conditions of 5.0 rpm and 25°C using a cone-plate viscometer (trade name TVE-35, manufactured by Toki Sangyo Co., Ltd.).

＜Gel fraction＞

The gel fraction was measured by the method described in the specification. It should be noted that "S1214" (manufactured by Matsunami Glass Industries, Ltd.) was used as a glass plate (slide). The coated light moisture curing resin composition was irradiated with ultraviolet rays of 1500mJ/ ^cm2 at a wavelength of 365nm by a UV-LED irradiator (manufactured by Seace Co., Ltd.). The immersion in THF was carried out using 100ml of THF added to a glass bottle while gently stirring. As a 200-mesh metal mesh, "True Brass 200 Mesh (wire diameter 50μm mesh 77μm)" (manufactured by Mesh Co., Ltd.) was used. The light moisture curing resin composition in the light-cured state after immersion was washed 5 times using new 5ml of THF each time. The swollen gel was dried by standing in a thermostat set at 100°C for 2 hours. In the above operation, all THF used was dried THF.

Based on the gel fraction measured as described above, the deep curability of the optical moisture curable resin composition was evaluated. The evaluation criteria for the deep curability are as follows.

A: More than 15%

B: 10% or more and 15% or less

C: less than 10%

＜Initial shear force＞

As shown in Figures 2(a) and (b), the optical moisture curable resin composition 20 was applied to the aluminum substrate 21 at room temperature (25°C) using the above-mentioned dispensing device in a manner of 1.0±0.1 mm in width, 25 mm in length, and 0.4±0.1 mm in thickness. Furthermore, the optical moisture curable resin composition 20 was photocured by irradiating 1500 mJ/ ^cm2 of ultraviolet light with a wavelength of 365 nm using a linear LED irradiator (manufactured by HOYA). Then, the glass plate 22 was bonded to the aluminum substrate 21 via the optically cured optical moisture curable resin composition 20, and the coated area was pressed at 0.08 MPa for 120 seconds using a weight to obtain a sample 23 for initial shear force evaluation.

Then, the aluminum substrate 21 and the glass plate 22 were stretched at a speed of 10 mm/min in the shear direction S using a tensile tester ("tensile compression tester SVZ-50NB", manufactured by Imada Seisakusho) in an atmosphere of 25°C, and the maximum stress when the aluminum substrate 21 and the glass plate 22 peeled off was measured, which was set as the initial shear force. It should be noted that the tensile test was carried out within 150 seconds from the end of photocuring to the start of the tensile test. The initial shear force was evaluated according to the following evaluation criteria.

A: 0.3MPa or more

B: 0.2MPa or more and less than 0.3MPa

C: less than 0.2MPa

＜Initial creep force＞

As shown in Figures 3(a) and (b), the optical moisture curable resin composition 31 is applied to the polycarbonate substrate 30 at room temperature (25°C) in such a way that the dimensions of the four sides of the optical moisture curable resin composition 31 are 9.5cm×9.5cm and the thickness is 0.4±0.1mm. Furthermore, the ultraviolet rays with a wavelength of 365nm of 1500mJ/ ^cm2 are irradiated with a linear LED irradiator (manufactured by HOYA) to perform photocuring. Then, a glass plate 32 of 10cm×10cm and a thickness of 12mm (manufactured by Japan Test Paner Co., Ltd.) is attached to the polycarbonate substrate 30 via the optically cured optical moisture curable resin composition 31, and a weight is used to press the coated area at 0.08MPa for 120 seconds to obtain a sample 33 for initial creep force evaluation.

Then, the sample 33 for initial creep force evaluation was vertically erected and placed in an environment of 25°C and 50%RH for 1 hour, and the distance h by which the glass plate 32 deviated after the placement was measured. It should be noted that the initial creep force test was performed within 300 seconds from the end of photocuring to the start of the initial creep force test. Based on the distance h, the initial creep force was evaluated according to the following evaluation criteria. It should be noted that a short distance h means a high initial creep force.

A: Distance h is less than 0.10mm

B: Distance h is 0.10 mm or more and 0.15 mm or less

C: Distance h exceeds 0.15 mm

＜Inside-outside ratio a/b＞

The inside-outside ratio a/b was measured by the method described in the specification. It should be noted that, as the aluminum substrate and the glass plate, an aluminum alloy "A6063S" with a size of 2mm×25mm×60mm and a glass plate with a smooth surface that was ultrasonically cleaned for 5 minutes were used respectively. The coating of the moisture-curing resin composition was carried out at room temperature (25°C) using the "SHOTMASTER300SX" made by Musashi Engineering as a dispensing device, and was linearly coated on the aluminum substrate in a manner of 1.0±0.1mm in width, 25mm in length, and 0.4±0.1mm in thickness. Next, the applied light moisture-curing resin composition was irradiated with ultraviolet rays of 1500mJ/ ^cm2 at a wavelength of 365nm by a linear LED irradiator (manufactured by HOYA Co., Ltd.). The crimping of the glass plate to the aluminum substrate was carried out using a weight as a weight, and the widths a1 and b1 were measured 5 minutes after the weight was removed. The widths a1 and b1 after crimping were measured by observing the crimping surface from the glass plate side using a microscope.

The urethane resin raw material used in each of the Examples and Comparative Examples was produced by the following method.

[Synthesis Example 1]

＜PC urethane resin raw materials＞

100 parts by mass of polycarbonate diol (a compound represented by formula (1), 90 mol% of R is 3-methylpentylene and 10 mol% is 1,6-hexylene, manufactured by Kuraray Co., Ltd., trade name "Kuraraypolyol C-1090") as a polyol compound and 0.01 parts by mass of dibutyltin dilaurate were added to a 500 mL removable flask. The contents of the flask were stirred and mixed at 100°C for 30 minutes under vacuum (below 20 mmHg). Then, the pressure was set to normal, 50 parts by mass of diphenylmethane diisocyanate (manufactured by Nissou Shoji Co., Ltd., trade name "Pure MDI") as a polyisocyanate compound were added, and the mixture was stirred at 80°C for 3 hours to react, thereby obtaining a moisture-curable urethane resin (PC urethane resin raw material) having a polycarbonate skeleton and isocyanate groups at both ends. The weight average molecular weight of the obtained urethane resin raw material was 6700.

[Example 1]

As shown in Table 4, 60 parts by mass of each raw material constituting the moisture-curable resin a was added to 40 parts by mass of acrylic B. Acrylic B is a material obtained by mixing each compound at the mixing ratio described in Table 2. As moisture-curable resin a, a PC urethane resin raw material and a PC polyol were sequentially added to acrylic B at the mass ratio described in Table 3 to obtain a mixture. As PC polyol, the polycarbonate diol used in Synthesis Example 1 was used.

The obtained mixture was stirred at 50° C. to react the polyol with a part of the urethane resin raw material to synthesize a moisture-curable urethane resin with chain extension and residual isocyanate groups, thereby obtaining a mixture of acrylic B (radical polymerizable compound) and moisture-curable urethane resin.

To the obtained mixture of acrylic B and moisture-curable urethane resin, a photoradical polymerization initiator, a filler, and a colorant were added and further mixed according to the compounding of Table 4 to obtain an optical moisture-curable resin composition. The weight average molecular weight, OD value, viscosity, and gel fraction of the obtained optical moisture-curable resin composition were measured, and the deep curability was further evaluated.

[Examples 2 to 4, Comparative Examples 1 to 3]

The same procedure as in Example 1 was carried out except that the type and blending amount of the colorant were changed as shown in Table 4.

[Examples 5 to 8, Comparative Examples 4 to 6]

As shown in Table 5, except that acrylic acid A was used instead of acrylic acid B, the optical moisture curable resin composition was obtained in the same manner as in Examples 1 to 4 and Comparative Examples 1 to 3. The weight average molecular weight, OD value, viscosity, internal and external ratio, initial shear force, and initial creep force of the obtained optical moisture curable resin composition were measured, and the initial shear force and initial creep force were evaluated.

Components other than the moisture-curable urethane resin used in each of the Examples and Comparative Examples are as shown in Table 1 below.

[Table 1]

Table 2 shows the acrylic acid systems A and B used in each of the examples and comparative examples.

[Table 2]

The moisture-curable resin a used in each of the examples and comparative examples is as shown in Table 3 below.

[Table 3]

[Table 4]

As shown in Table 4, even when the optical moisture curable resin compositions in Examples 1 to 4 were blackened to an OD value of 2 or more, zirconium nitride was used, so the gel fraction after photocuring became high and good photocurability was exhibited.

On the other hand, in Comparative Examples 1 to 3, titanium black was used instead of zirconium nitride, so that the gel fraction after photocuring became low and good photocurability could not be exhibited.

[Table 5]

As shown in Table 5, the optical moisture curable resin composition in each example has excellent photocurability due to the use of zirconium nitride even when the OD value is made 2 or more and blackened. Therefore, the initial shear force and initial creep force become good, and excellent initial adhesive force can be expressed.

On the other hand, in the comparative example using titanium black as a coloring agent instead of zirconium nitride, the photocurability was insufficient and the initial adhesive strength could not be excellent.

Claims (8)

1. A light moisture curable resin composition comprising: a radical polymerizable compound, a moisture curable resin, a photo radical polymerization initiator, and zirconium nitride, The OD value of the cured product having a thickness of 1 mm after photocuring is 2 or more. 2 . The optical moisture curable resin composition according to claim 1 , wherein the radical polymerizable compound includes a polyfunctional radical polymerizable compound. 3. The optical moisture curable resin composition according to claim 1 or 2, when applied to an aluminum substrate with a line width of 1.0 mm and photocured by irradiating ultraviolet rays of 1500 mJ/ ^cm2 , and a glass plate is pressed at 0.08 MPa for 120 seconds, if the average width of the bonding portion on the glass plate side is a and the average width of the bonding portion on the aluminum substrate side is b, then a/b is 0.5 or more and 0.95 or less. The optical moisture curable resin composition according to any one of claims 1 to 3, wherein the viscosity measured at 25°C and 5.0 rpm using a cone-plate viscometer is 40 Pa·s or more and 600 Pa·s or less. 5 . The optical moisture curable resin composition according to claim 1 , further comprising a filler. 6 . An adhesive for electronic components, comprising the optical moisture curable resin composition according to claim 1 . 7 . An adhesive for display elements, comprising the optical moisture curable resin composition according to claim 1 . 8 . A cured product of the optical moisture curable resin composition according to claim 1 .