TW201706319A - (meth)acrylate resin and optical member - Google Patents

Abstract

The purpose of the present invention is to provide: a (meth)acrylate resin which can be cured into a cured article having excellent heat resistance, moisture absorption resistance and yellowish discoloration resistance; a photocurable composition which contains the (meth)acrylate resin, and a cured product of the photocurable composition; and an optical member manufactured using the photocurable composition. A (meth)acrylate resin characterized by being a reaction product of which the essential reaction components are an aromatic diglycidyl ether compound (A), (meth)acrylic acid (B) and methacrylic anhydride (C); a photocurable composition containing the (meth)acrylate resin, and a cured product of the photocurable composition; and an optical member manufactured using the photocurable composition.

Description

(Meth) acrylate resin and optical member

The present invention relates to a (meth) acrylate resin excellent in heat resistance, moisture absorption resistance, and yellowing resistance of a cured product, a photocurable composition containing the same, a cured product thereof, and an optical member.

An on-chip lens mounted on an image sensor such as a CCD or a CMOS is widely used by a melting method in which a dot pattern is applied to a thermoplastic resin and a spherical lens is shaped by heat flow, but a spherical lens is used. Since the chromatic aberration is large, there is a limit to high definition and high sensitivity. Moreover, it is difficult to achieve lens formation with a narrow gap by this melting method. As a technique for reducing the chromatic aberration and achieving lens formation with a narrow gap, a shape transfer method in which a photocurable resin is shaped by a mold having an aspherical lens shape has been proposed. The photocurable resin is composed of a resin or a monomer having a photopolymerizable group such as a (meth) acrylonitrile group, and can have a low viscosity by containing a large amount of a low molecular weight component, so that a fine shape can be formed. Material. However, when used for a crystal-loaded lens, heat resistance or moisture resistance is insufficient and yellowing or deformation is likely to occur.

For example, a photocurable resin obtained by reacting a bisphenol A epoxy resin with methacrylic anhydride is known as a photocurable resin which is excellent in moisture absorption resistance (see Patent Document 1). Such a resin having a high aromatic ring content exhibits relatively high heat resistance, but is used for When the crystal lens is used, the heat resistance and the moisture resistance are insufficient, and yellowing or deformation is likely to occur.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-038029

Therefore, an object of the present invention is to provide a (meth) acrylate resin excellent in heat resistance, moisture absorption resistance, and yellowing resistance of a cured product, a photocurable composition containing the same, a cured product thereof, and an optical member. .

In order to solve the above problems, the inventors of the present invention have conducted an effort to find a cured product of a methacrylate resin obtained by reacting an aromatic diglycidyl ether compound with (meth)acrylic acid and methacrylic anhydride. The present invention has been completed in that it is excellent in heat resistance, moisture absorption resistance, and yellowing resistance.

That is, the present invention relates to a (meth) acrylate resin characterized by comprising an aromatic diglycidyl ether compound (A), (meth)acrylic acid (B), and methacrylic anhydride (C). ) a reactant as an essential reaction component.

The present invention further relates to a (meth) acrylate resin characterized by having a molecular structure represented by the following formula (1). In the formula, R ¹ is a hydrogen atom or a methyl group, and X is a structural moiety represented by any one of the following general formulae (2-1) to (2-8).

(wherein R ^{2 is} each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group; and R ^{3 is} independently a carbon number; Any of an alkyl group of 1 to 4, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and n is an integer of 1 to 4)

Y is a hydrogen atom or a methacryl fluorenyl group, and at least one of Y present in the resin is a methacryl fluorenyl group.

The present invention further relates to a photocurable composition containing the above (meth) acrylate resin and a photopolymerization initiator.

The present invention further relates to a cured product of the above curable composition.

The present invention further relates to an optical member in which a curable composition is used.

According to the present invention, a (meth) acrylate resin excellent in heat resistance, moisture absorption resistance, and yellowing resistance of a cured product, a photocurable composition containing the same, a cured product thereof, and an optical member can be provided.

Fig. 1 is a GPC chart of the (meth) acrylate resin (1) obtained in Example 1.

Hereinafter, the present invention will be described in detail.

The (meth) acrylate resin of the present invention is characterized in that it is an essential reaction of an aromatic diglycidyl ether compound (A), (meth)acrylic acid (B), and methacrylic anhydride (C). The reactants of the ingredients. That is, the present invention is conventionally used by using (meth)acrylic acid (B) and methacrylic anhydride (C) as a (meth) acrylate-forming agent of the aromatic diglycidyl ether compound (A). The photocurable resin material which is excellent in heat resistance, moisture absorption resistance, and yellowing resistance of the cured product is successfully obtained as compared with the epoxy acrylate resin.

Examples of the aromatic diglycidyl ether compound (A) used in the present invention include a bisphenol epoxy resin, a biphenyl epoxy resin, a phenyl ether epoxy resin, a naphthalene ether epoxy resin, and a phenol aryl group. Alkyl epoxy resin, naphthol aralkyl epoxy resin, dicyclopentadiene-phenol plus More specifically, a compound represented by any one of the following structural formulae (3-1) to (3-8), and the like can be mentioned.

In the formula, R ^{2 is} each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and R ^{3 is} independently a carbon number of 1 Any of an alkyl group of ~4, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, G represents an epoxypropyl group, and n is an integer of 1 to 4)

These may be used alone or in combination of two or more. In particular, the compound represented by the above structural formula (3-1) is preferred from the viewpoint of obtaining a methacrylate resin excellent in heat resistance, moisture absorption resistance, and yellowing resistance of the cured product.

The (meth)acrylic acid (B) may be either acrylic acid or methacrylic acid, or both may be used in combination. Among them, methacrylic acid is preferred in terms of a (meth) acrylate resin which is excellent in heat resistance of a cured product. Further, acrylic acid is preferred in that it is hard to generate a gas when the cured product is heated.

In the production of the (meth) acrylate resin of the present invention, the reaction ratio of the above aromatic diglycidyl ether compound (A), (meth)acrylic acid (B), and methacrylic anhydride (C), It is preferred to use (meth)acrylic acid (B) and methacrylic anhydride in a range of from 0.9 to 1.1 moles in total with respect to the epoxy group 1 mole in the aromatic diglycidyl ether compound (A). (C).

Further, in terms of a methacrylate resin which is excellent in heat resistance, moisture absorption resistance and yellowing resistance of a cured product, it is preferably (meth)acrylic acid (B) and methacrylic anhydride (C). The ratio of the ear ratio [(B)/(C)] is in the range of 1/9 to 6/4.

In the present invention, the method for producing the (meth) acrylate resin is not particularly limited, and examples thereof include an organic solvent in the presence of an esterification reaction catalyst, an antioxidant, and a polymerization inhibitor, if necessary. The aromatic diglycidyl ether compound (A), (meth)acrylic acid (B), and methacrylic anhydride (C) are reacted in a temperature range of 100 to 150 ° C for about 5 to 12 hours.

The (meth) acrylate resin of the present invention produced by such a method is, for example, a molecular structure represented by the following formula (1).

In the formula, R ¹ is a hydrogen atom or a methyl group, and X is a structural moiety represented by any one of the following general formulae (2-1) to (2-8).

(wherein R ^{2 is} each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group; and R ^{3 is} independently a carbon number; Any of an alkyl group of 1 to 4, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and n is an integer of 1 to 4)

Y is a hydrogen atom or a methacryl fluorenyl group, and at least one of Y present in the resin is a methacryl oxime group.

Specific examples of the resin component having the molecular structure represented by the above formula (1) include compounds represented by any one of the following formulae (1-1) to (1-3).

In the formula, R ¹ is a hydrogen atom or a methyl group, and X is a structural moiety represented by any one of the following general formulae (2-1) to (2-8).

(wherein R ^{2 is} each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group; and R ^{3 is} independently a carbon number; Any of an alkyl group of 1 to 4, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, and n is an integer of 1 to 4)]

The methacrylate resin of the present invention preferably has a (meth) acrylonitrile equivalent of 160 to 230 g, which is calculated based on the amount of the raw material added, in terms of heat resistance, moisture absorption resistance, and yellowing resistance of the cured product. / range of equivalents.

The photocurable composition of the present invention contains the above methacrylate resin and a photopolymerization initiator.

The photopolymerization initiator used herein may, for example, be diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one or benzoin dimethyl ketal. 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl) ketone , 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-morpholinyl (4-thiomethylphenyl)propan-1-one, 2-benzyl-2-dimethylamino-1 -(4-morpholinylphenyl)butanone of acetophenone; such as benzoin, benzoin methyl ether, benzoin of benzoin isopropyl ether; such as 2,4,6-trimethylbenzoin diphenylphosphine oxide a fluorenylphosphine oxide system; an intramolecular bond cleavage type photopolymerization initiator such as benzophenone or methyl benzoate; or a benzophenone or methyl benzoyl benzoate-4-phenyl Benzene, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzylidene-4'-methyl-diphenyl sulfide, acrylated benzophenone, 3, 3',4,4'-tetra(perbutyl peroxide) benzophenone, 3,3'-dimethyl-4-methoxybenzophenone benzophenone; -isopropyl 9-oxosulfur 2,4-dimethyl 9-oxosulfur 2,4-diethyl 9-oxosulfur 2,4-dichloro 9-oxosulfur 9-oxygen sulfur Aminobenzophenone series such as mazinone, 4,4'-diethylaminobenzophenone; and 10-butyl-2-chloroacridone, 2-ethylhydrazine , 9,10-phenanthrenequinone, camphorquinone and other intramolecular hydrogen abstraction photopolymerization initiator. These may be used alone or in combination of two or more.

Commercial products of such photopolymerization initiators include, for example, "Irgacure-184", "Irgacure-149", "Irgacure-261", "Irgacure-369", "Irgacure-500", "Irgacure-651". , Irgacure-754, Irgacure-784, Irgacure-819, Irgacure-907, Irgacure-1116, Irgacure-1664, Irgacure-1700, Irgacure-1800, Irgacure-1850", "Irgacure-2959", "Irgacure-4043", "Darocure-1173" (manufactured by Ciba Specialty Chemicals), "Lucirin TPO" (manufactured by BASF), "Kayacure-DETX", "Kayacure-MBP" "Kayacure-DMBI", "Kayacure-EPA", "Kayacure-OA" (manufactured by Nippon Kayaku Co., Ltd.), "Vicure-10", "Vicure-55" (manufactured by Stauffer Chemical Co., Ltd.), "Trigonal P1" (made by akzo), "Sandray 1000" (made by SANDOZ), "DEAP" (made by Upjohn), "Quantacure-PDO", "Quantacure-ITX", "Quantacure-EPD" (made by Ward Blenkinsop), etc. .

The amount of the photopolymerization initiator to be added is, for example, 1 to 20 parts by mass based on 100 parts by mass of the photocurable composition.

The photocurable composition of the present invention may further contain a (meth) acrylate compound or a photosensitizer other than the above methacrylate resin, a curing accelerator, an organic solvent, a non-reactive resin, a filler, an inorganic filler, Organic filler, coupling agent, adhesion-imparting agent, antifoaming agent, leveling agent, adhesion aid, mold release agent, lubricant, ultraviolet absorber, antioxidant, heat stabilizer, plasticizer, flame retardant, pigment Additives such as dyes.

Examples of the other (meth) acrylate compound include n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, and n-pentyl (meth) acrylate. n-Hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, glycidyl (meth)acrylate, and chloroform Porphyrin (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 2-methoxy (meth) acrylate Ethyl ethyl ester, 2-butoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, 4-mercaptophenoxyethylene glycol (meth) acrylate, tetramethyl methacrylate (meth) acrylate, caprolactone modified tetrahydrofurfuryl (meth) acrylate, cyclohexyl (meth) acrylate , cyclohexylmethyl (meth)acrylate, cyclohexylethyl (meth)acrylate, isodecyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentyloxy (meth)acrylate Ester, dicyclopentenyl (meth)acrylate, (methyl) Dicyclopentenyloxyethyl acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, phenoxyethyl (meth) acrylate, phenoxy 2-methyl (meth) acrylate Ethyl ester, phenoxyethoxyethyl (meth)acrylate, p-cumylphenoxyethyl (meth)acrylate, phenoxybenzyl (meth)acrylate, (meth)acrylic acid 2 -hydroxy-3-phenoxypropyl ester, phenylbenzyl (meth)acrylate, phenylphenoxyethyl acrylate, 2-propenyloxyethyl hexahydrophthalate, the following formula ( a mono (meth) acrylate compound such as a mono (meth) acrylate compound containing an anthracene skeleton represented by (5);

Wherein X is a hydrogen atom or a hydroxyl group, and R ¹ and R ⁴ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; R ² is a hydrogen atom or a methyl group; and R ³ is a direct bond or a sub Methyl, m is 0 or 1]

[wherein, two X's are each independently a hydrogen atom or a hydroxyl group, and two R ₁ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₂ is a hydrogen atom or a methyl group, m and n Independently 0 or 1]

Ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6- Hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, bisphenol A di(meth)acrylate, double Phenol F di(meth)acrylate, dicyclopentanyl (meth)acrylate, glycerol di(meth)acrylate, neopentyl glycol hydroxypivalate di(meth)acrylate, caprolactone modification Hydroxy-pivalic acid neopentyl glycol di(meth)acrylate, tetrabromobisphenol A di(meth)acrylate, hydroxypivalaldehyde-modified trimethylolpropane di(meth)acrylate, 1 , 4-cyclohexanedimethanol di(meth)acrylate, bis[(meth)acrylenylmethyl]biphenyl, the ruthenium-containing skeleton represented by the following formula (6) or (7) a di(meth) acrylate compound such as a (meth) acrylate compound;

[wherein, X is each independently a hydrogen atom or a hydroxyl group, and R ^{1 is} each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ^{2 is} independently a hydrogen atom or a methyl group, and R ^{3 is} independently The ground is a direct bond or a methylene group, and m and n are each independently 0 or 1]

[wherein, two X are each independently a hydrogen atom or a hydroxyl group, and two R ₁ are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and two R ₂ are each independently a hydrogen atom or a Base, m and n are independently 0 or 1]

Trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, tris(meth)acrylate, di-trimethylolpropane tetra(meth)acrylate, two a trifunctional or higher (meth) acrylate compound such as pentaerythritol penta (meth) acrylate or dipentaerythritol hexa (meth) acrylate; butane-1,4-diisocyanate, hexa Methyl diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, benzodimethyl diisocyanate, m-tetramethylbenzene Methyl diisocyanate, cyclohexane-1,4-diisocyanate, isophorone diisocyanate, diazonic acid diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanate group) Methyl)cyclohexane, methylcyclohexane diisocyanate, 1,5-naphthalene diisocyanate, 4,4'-diphenylmethane diisocyanate, 2,2'-bis(p-phenylisocyanate)propane, 4, 4'-dibenzyldiisocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-benzenediisocyanate, 1,4-phenylene diisocyanate, toluene diisocyanate Diisocyanate compounds such as esters or such urate modified bodies with 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, glyceryl diacrylate, trimethylolpropane diacrylate (meth) propyl obtained by reacting a hydroxyl group-containing (meth) acrylate compound such as pentaerythritol triacrylate or dipentaerythritol pentaacrylate Ethyl amide and the like. These other (meth) acrylate compounds may be used alone or in combination of two or more.

The cured product of the photocurable composition of the present invention exhibits high heat resistance, moisture resistance, and yellowing resistance, and thus can be used for various applications such as electronic parts, molded articles, and coating applications. In particular, it is effective to utilize the characteristics excellent in yellowing resistance and is preferably used for optical member applications. Examples of the optical member include a lens lens, a crystal lens for an image sensor such as a CCD or a CMOS, a plastic lens such as a Fresnel lens or a 稜鏡 lens, and an optical protective agent, a hard coating agent, an anti-reflection film, and an optical fiber. , optical waveguides, holograms, 稜鏡 lenses, LED sealing materials, coating materials for solar cells, etc.

The crystal carrier lens or the ruthenium lens is produced, for example, by a shape transfer method using a mold such as a mold or a resin mold in which a lens pattern is formed. Specifically, a method in which a photocurable composition is applied to a shaping die, a transparent substrate is superposed on the surface of the composition, and an active energy ray is irradiated from the transparent substrate side to be cured. The transparent substrate used herein may, for example, be a plastic substrate made of an acrylic resin, a polycarbonate resin, a polyester resin, a polystyrene resin, a fluororesin or a polyimide resin, or glass.

The lens sheet produced by this method can be directly used by being attached to a transparent substrate, or the transparent substrate can be peeled off and used as a lens alone. In the case of being directly applied to a transparent substrate, in order to improve the adhesion between the lens and the transparent substrate, it is preferred to perform an adhesion improving treatment such as a primer treatment on the surface of the transparent substrate in advance. On the other hand, in the case where the transparent substrate is used after being peeled off, it is preferred that the surface of the transparent substrate is treated in advance by a polyfluorene oxide or a fluorine-based release agent so that the transparent substrate can be easily peeled off.

In the case where the photocurable composition of the present invention is used for such a shaped lens Preferably, the methacrylate resin of the present invention and the above other (meth) acrylate compound are used in combination, and the viscosity (25 ° C) of the photocurable composition is adjusted to be in the range of 100 mPa ‧ to 800 mPa ‧ s . The other (meth) acrylate compound to be used is appropriately selected depending on the desired properties. For example, it is preferred to adjust the refractive index of the cured product to 1.5560 or more.

[Examples]

Hereinafter, the present invention will be described in more detail by way of examples and comparative examples.

Production of Example 1 (meth) acrylate resin (1)

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.6 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 86 parts by mass of methacrylic acid, 154 parts by mass of methacrylic anhydride, and 1.8 parts by mass of triphenylphosphine were added. The (meth) acrylate resin (1) was obtained by performing an esterification reaction at 110 ° C for 10 hours while blowing air. The (meth)acryl oxime equivalent calculated from the amount of the raw material of the (meth) acrylate resin (1) was 205 g/eq. Further, the molar ratio [(B)/(C)] of methacrylic acid (B) to methacrylic anhydride (C) was 5/5.

Example 2 Production of (meth) acrylate resin (2)

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.6 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 52 parts by mass of methacrylic acid, 216 parts by mass of methacrylic anhydride, and 1.8 parts by mass of triphenylphosphine were added. The (meth) acrylate resin (2) was obtained by blowing air at 110 ° C for 10 hours for esterification. According to the (meth) acrylate tree The (meth)acryl oxime equivalent calculated from the amount of the raw material of the fat (2) was 188 g/eq. Further, the molar ratio [(B)/(C)] of methacrylic acid (B) to methacrylic anhydride (C) was 3/7.

Production of Example 3 (meth) acrylate resin (3)

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.7 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 17 parts by mass of methacrylic acid, 278 parts by mass of methacrylic anhydride, and 2.0 parts by mass of triphenylphosphine were added. The (meth) acrylate resin (3) was obtained by blowing air at 110 ° C for 10 hours for esterification. The (meth) acrylonitrile equivalent calculated from the amount of the raw material of the (meth) acrylate resin (3) was 176 g/eq. Further, the molar ratio [(B)/(C)] of methacrylic acid (B) to methacrylic anhydride (C) was 1/9.

Production of Example 4 (meth) acrylate resin (4)

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.6 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 72 parts by mass of acrylic acid, 154 parts by mass of methacrylic anhydride, and 1.8 parts by mass of triphenylphosphine were added and blown. The air was subjected to an esterification reaction at 110 ° C for 10 hours to obtain a (meth) acrylate resin (4). The (meth)acryl oxime equivalent calculated from the amount of the raw material of the (meth) acrylate resin (4) was 200 g/eq. Further, the molar ratio [(B)/(C)] of the acrylic acid (B) to the methacrylic anhydride (C) was 5/5.

Production of Example 5 (meth) acrylate resin (5)

Adding a bisphenol A type epoxy tree to a flask equipped with a thermometer, a stirrer, and a reflux cooler 374 parts by mass of "EPICLON 850-S" epoxy equivalent 187 g/eq. manufactured by DIC Co., Ltd., and 0.6 parts by mass of dibutylhydroxytoluene as an antioxidant, p-methoxyphenol as a thermal polymerization inhibitor After 0.2 parts by mass, 43 parts by mass of acrylic acid, 216 parts by mass of methacrylic anhydride, and 1.8 parts by mass of triphenylphosphine were added, and the mixture was subjected to an esterification reaction at 110 ° C for 10 hours while blowing air to obtain (meth)acrylic acid. Ester resin (5). The (meth)acryl oxime equivalent calculated from the amount of the raw material of the (meth) acrylate resin (5) was 186 g/eq. Further, the molar ratio [(B)/(C)] of the acrylic acid (B) to the methacrylic anhydride (C) was 3/7.

Production of Example 6 (meth) acrylate resin (6)

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.7 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 14 parts by mass of acrylic acid, 278 parts by mass of methacrylic anhydride, and 2.0 parts by mass of triphenylphosphine were added and blown. The air was subjected to an esterification reaction at 110 ° C for 10 hours to obtain a (meth) acrylate resin (6). The (meth) acrylonitrile equivalent calculated from the amount of the raw material of the (meth) acrylate resin (6) was 175 g/eq. Further, the molar ratio [(B)/(C)] of the acrylic acid (B) to the methacrylic anhydride (C) was 1/9.

Comparative Production Example 1 (Meth) acrylate resin (1')

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.5 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 172 parts by mass of methacrylic acid and 1.6 parts by mass of triphenylphosphine were added, and the air was blown at 110 ° C while blowing air. It is subjected to an esterification reaction for 10 hours to obtain (A Base) acrylate resin (1'). The (meth)acryl oxime equivalent calculated from the amount of the raw material of the (meth) acrylate resin (1') was 273 g/eq.

Comparative Production Example 2 (Meth) acrylate resin (2')

374 parts by mass of bisphenol A type epoxy resin ("EPICLON 850-S" epoxy equivalent 187 g/eq. by DIC Co., Ltd.) was added to a flask equipped with a thermometer, a stirrer, and a reflux cooler, and added as an anti-antibody. 0.5 parts by mass of dibutylhydroxytoluene as an oxidizing agent and 0.2 parts by mass of p-methoxyphenol as a thermal polymerization inhibitor, 144 parts by mass of acrylic acid and 1.6 parts by mass of triphenylphosphine were added, and the air was blown at 110 ° C while being blown. The esterification reaction was carried out for 10 hours to obtain a (meth) acrylate resin (2'). The (meth)acryl oxime equivalent calculated from the amount of the raw material of the (meth) acrylate resin (2') was 259 g/eq.

Examples 7 to 12, Comparative Examples 1, 2

Using the (meth) acrylate resins obtained in Examples 1 to 6 and Comparative Production Examples 1 and 2, a curable composition and a cured product were prepared in accordance with the following procedures, and various evaluation tests were carried out. The results are shown in Table 1.

Preparation of hardenable composition

1 g of a photopolymerization initiator ("Irgacure 184D" manufactured by BASF Corporation) was added to 100 g of the (meth) acrylate resin to prepare a curable composition.

Determination of glass transition temperature

The curable composition obtained previously was applied onto an acrylic plate so as to have a film thickness of 100 μm, and irradiated with ultraviolet rays of 2000 mJ/cm ² by a high pressure mercury lamp to obtain a cured product.

A test piece of 6 mm × 25 mm was cut out from the obtained cured product, and a viscoelasticity measuring device (DMA: solid viscoelasticity measuring device "RSA-G2" manufactured by Rheometrics Co., Ltd., stretching method was used: The temperature at which the frequency was changed to 1 Hz and the temperature rise rate was 3 ° C/min. The temperature at which the change in the elastic modulus was maximum (the maximum rate of change of tan δ) was evaluated as the glass transition temperature.

Determination of water absorption

A 6 mm × 25 mm test piece was cut out from the same cured product as the glass transition temperature, and immersed in water at 23 ° C for 24 hours. The weight change rate before and after the immersion was evaluated as the water absorption rate.

Evaluation of yellowing resistance

The curable composition obtained previously was applied onto a glass plate so as to have a film thickness of 100 μm, and an ultraviolet film of 2000 mJ/cm ^{2 was} irradiated with a high-pressure mercury lamp to obtain a laminated film.

The obtained laminated film was heated in an oven at 265 ° C for 3 minutes. The transmittance (%) of 420 nm light was measured for the test piece before and after heating, and evaluated based on the difference between the two values.

Gas generation evaluation

The curable composition obtained previously was applied onto a glass plate so as to have a film thickness of 100 μm, and an ultraviolet film of 1000 mJ/cm ² or 2000 mJ/cm ^{2 was} irradiated with a high-pressure mercury lamp to obtain a laminated film.

The obtained laminated film was heated on a hot plate at 265 ° C for 3 minutes. It was visually observed whether or not gas was generated at this time and evaluated. No gas is produced: ○, gas is generated and foaming is present: ×

Claims (6)

A (meth) acrylate resin which is a reaction product of an aromatic diglycidyl ether compound (A), (meth)acrylic acid (B), and methacrylic anhydride (C) as essential reaction components. A (meth) acrylate resin having a molecular structure represented by the following formula (1), In the formula, R ¹ is a hydrogen atom or a methyl group, and X is a structural moiety represented by any one of the following general formulae (2-1) to (2-8). (wherein R ^{2 is} each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group; and R ^{3 is} independently a carbon number; Any of an alkyl group having 1 to 4, an alkoxy group having 1 to 4 carbon atoms, or a phenyl group, n being an integer of 1 to 4) Y is a hydrogen atom or a methacryl fluorenyl group, and is present in the resin At least one of Y is a methacryl oxime group. The (meth) acrylate resin according to claim 1 or 2, wherein the (meth) acrylonitrile equivalent is in the range of 160 to 230 g / equivalent. A curable composition comprising the (meth) acrylate resin according to any one of claims 2 to 3, and a photopolymerization initiator. A cured product which is a cured product of the curable composition of claim 4 of the patent application. An optical member obtained by using the curable composition of claim 4 of the patent application.