JPWO2015163216A1 - Curable composition and cured product thereof - Google Patents

Abstract

Provided is a curable composition capable of forming a cured product excellent in transparency, adhesion to various plastic substrates, and hydrolysis resistance. The curable composition of this invention contains the following component. Component (A): Epoxy group and polymerizable unsaturated group-containing monomer component (B): At least one polymer selected from polyester, epoxy resin, and polyurethane, which may have a (meth) acryloyloxy group Component (C): Radical Polymerization Initiator The curable composition of the present invention preferably further contains a polymerizable unsaturated group-containing monomer containing no epoxy group as the component (D).

Description

  The present invention relates to a curable composition useful as an adhesive for bonding a transparent plastic substrate, a material for forming a thin light guide plate used in a backlight device constituting a liquid crystal display device, and the like. This application claims the priority of Japanese Patent Application No. 2014-091832 for which it applied to Japan on April 25, 2014, and uses the content here.

  As the liquid crystal display device, an edge light type surface light source device is often used. Such a surface light source device includes a light guide plate that emits light from the light source to the liquid crystal display panel side, and a light source such as an LED (light emitting diode) disposed on the side of the light guide plate. The light guide plate has a concavo-convex shape on the surface thereof, and has an effect of guiding the light incident from the side portion (light incident portion) by irregularly reflecting the light inside the plate and emitting it to the liquid crystal display panel side.

  The light guide plate is required to have transparency, heat resistance, toughness and the like. In order to satisfy these requirements, a transparent plastic substrate such as a polycarbonate plate or a polymethyl methacrylate plate is mainly used. In recent years, the thinning of the light guide plate has been demanded with the thinning of the liquid crystal display device.

  As a method for manufacturing the light guide plate, a method by injection molding is known, but it has been difficult to cope with the thinning of the light guide plate by this method. As a method capable of coping with thinning of the light guide plate, a method of performing surface processing such as dot printing or laser processing on a transparent plastic substrate is known. However, this method has a problem that the process is complicated.

  As a simple method that can cope with the thinning of the light guide plate, Patent Document 1 discloses that a thin film layer having irregularities on the surface obtained by imprinting a coating film made of an ultraviolet curable resin is a polycarbonate thin film. A method of manufacturing a light guide plate by laminating on a layer is described.

JP 2008-140782 A

A material for forming a thin film layer having irregularities on the surface by imprint molding is required to have excellent adhesion to a transparent plastic substrate such as a polycarbonate substrate and to form a cured product having excellent transparency. As such a forming material, for example, it is considered to use a resin composition containing a binder polymer and a polymerization initiator described in JP-A-2008-89859.
However, the present inventors have found that the cured product of the resin composition is easily hydrolyzed under high-temperature and high-humidity conditions (that is, inferior in hydrolysis resistance), and is transparent and adheres to the transparent plastic substrate by hydrolysis. I found that the sex declined.

Therefore, the objective of this invention is providing the curable composition which can form the hardened | cured material excellent in transparency, adhesiveness with various plastic base materials, and hydrolysis resistance.
Another object of the present invention is a curability that can form a cured product that is excellent in transparency, adhesion to various plastic substrates, and hydrolysis resistance, and has a small difference in refractive index from various plastic substrates. It is to provide a composition.

  As a result of intensive studies to solve the above problems, the present inventors have been able to form a cured product excellent in transparency and adhesion to various plastic substrates, and include a resin composition containing the binder polymer and a polymerization initiator. In addition, when a component having an action of capturing an acid that catalyzes a hydrolysis reaction of the binder polymer or its cured product is added, the progress of hydrolysis can be suppressed even under a high temperature and high humidity condition, and the component that captures the acid As a result, it has been found that an epoxy group and a polymerizable unsaturated group-containing monomer are effective. The present invention has been completed based on these findings.

That is, this invention provides the curable composition containing the following component.
Component (A): Epoxy group and polymerizable unsaturated group-containing monomer component (B): At least one polymer selected from polyester, epoxy resin, and polyurethane, which may have a (meth) acryloyloxy group Component (C): radical polymerization initiator

  The present invention also provides the above-mentioned curable composition containing a polymerizable unsaturated group-containing monomer not containing an epoxy group as component (D).

  The present invention also provides the curable composition further containing an antioxidant as the component (E).

  The present invention also provides the above curable composition containing a cationic polymerization initiator as component (F).

  The present invention also provides an adhesive containing the curable composition.

  The present invention also provides an optical member including a structure in which a transparent plastic substrate is fixed by a cured product of the adhesive.

  The present invention also provides a cured product of the curable composition.

  The present invention also provides a light guide plate having a structure in which a layer having a concavo-convex shape is laminated on a surface of a transparent plastic substrate, which is made of a cured product of the curable composition.

  The present invention also provides a liquid crystal display device comprising the light guide plate.

That is, the present invention relates to the following.
[1] A curable composition containing the following components.
Component (A): Epoxy group and polymerizable unsaturated group-containing monomer component (B): At least one polymer selected from polyester, epoxy resin, and polyurethane, which may have a (meth) acryloyloxy group Component (C): radical polymerization initiator [2] In [1], the epoxy group and polymerizable unsaturated group-containing monomer in component (A) is a monomer containing an alicyclic epoxy group and a (meth) acryloyloxy group. The curable composition as described.
[3] The curable composition according to [1], wherein the epoxy group and polymerizable unsaturated group-containing monomer in the component (A) is an alicyclic epoxy group-containing (meth) acrylate monomer represented by the formula (a). .
[4] The content of component (A) (when two or more types are contained, the total amount thereof) is 1 to 60% by weight of the total amount (100% by weight) of the curable composition, any of [1] to [3] The curable composition as described in any one.
[5] The polymer in component (B) is an epoxy (meth) acrylate, polyester (meth) acrylate, or polyurethane (meth) acrylate containing two or more (meth) acryloyloxy groups in one molecule [ [1] The curable composition according to any one of [4].
[6] The content of component (B) (when 2 or more types are contained, the total amount thereof) is 5 to 80% by weight of the total amount (100% by weight) of the curable composition, any of [1] to [5] The curable composition as described in any one.
[7] The curable composition according to any one of [1] to [6], wherein the component (C) is a radical photopolymerization initiator.
[8] The component (C) contains an alkylphenone compound and an acylphosphine oxide compound in a ratio of 2/1 to 30/1 [former / latter (weight ratio)]. The curable composition as described in any one.
[9] The content of component (C) (the total amount when containing two or more) is 0.5 to 10 parts by weight with respect to 100 parts by weight of the curable compound contained in the curable composition [1. ] The curable composition as described in any one of [8].
[10] The curable composition according to any one of [1] to [9], further containing a polymerizable unsaturated group-containing monomer not containing an epoxy group as the component (D).
[11] The curable composition according to [10], wherein the polymerizable unsaturated group-containing monomer not containing an epoxy group in the component (D) is a (meth) acrylate monomer represented by the formula (d).
[12] The content of component (D) (the total amount when two or more are contained) is 5 to 80% by weight of the total amount (100% by weight) of the curable composition, as described in [10] or [11]. Curable composition.
[13] The total amount of the compounds contained in the component (B) or the component (D) and containing an aromatic ring is 20 to 99% by weight of the total content of the component (B) and the component (D). [10] The curable composition according to any one of [12].
[14] The curable composition according to any one of [1] to [13], further comprising an antioxidant as the component (E).
[15] The curable composition according to [14], wherein the antioxidant contains a phenolic antioxidant and a phosphorus antioxidant in a ratio of 55/45 to 80/20 [former / latter (weight ratio)]. .
[16] The curable composition according to any one of [1] to [15], further comprising a cationic polymerization initiator as the component (F).
[17] The content of component (F) (when two or more types are contained, the total amount) is 0.3 to 1 part by weight with respect to 100 parts by weight of the curable compound contained in the curable composition [16. ] The curable composition as described in above.
[18] The curable composition according to any one of [1] to [17], wherein the viscosity [at 25 ° C., shear rate 10 (1 / s)] is 50 to 1000 mPa · s.
[19] An adhesive comprising the curable composition according to any one of [1] to [18].
[20] A thin light guide plate forming material comprising the curable composition according to any one of [1] to [18].
[21] An optical member including a structure in which a transparent plastic substrate is fixed by a cured product of the adhesive according to [19].
[22] A cured product of the curable composition according to any one of [1] to [18].
[23] The cured product according to [22], wherein the cured product (thickness: 1 mm) has a total light transmittance (based on JIS K7361-1) in the visible light wavelength region of 88% or more.
[24] The cured product according to [22] or [23], wherein the turbidity (based on JIS K7136) of the cured product (thickness 1 mm) is 1% or less.
[25] The cured product according to any one of [22] to [24], wherein the cured product has a refractive index (at 25 ° C., at a wavelength of 589.3 nm) of 1.50 or more.
[26] The total light transmittance (based on JIS K7361-1) in the visible light wavelength region of the cured product (thickness 1 mm) after being exposed to 60 ° C. and 90% humidity for 100 hours is 88% or more. The cured product according to any one of [22] to [25].
[27] Any of [22] to [26], wherein the turbidity (based on JIS K7136) of a cured product (thickness 1 mm) after being exposed to 60 ° C. and 90% humidity for 100 hours is 2% or less. Hardened | cured material as described in any one.
[28] A light guide plate having a structure in which a surface having a concavo-convex shape is laminated on a surface of a transparent plastic substrate, which is made of a cured product of the curable composition according to any one of [1] to [18]. .
[29] A liquid crystal display device comprising the light guide plate according to [28].

  Since the curable composition of this invention has the said structure, it can be excellent in adhesiveness with various plastic base materials, such as a polycarbonate and a polymethylmethacrylate, and can form the hardened | cured material excellent in transparency. Furthermore, the cured product of the curable composition of the present invention has excellent hydrolysis resistance, can suppress the progress of hydrolysis even under high-temperature and high-humidity conditions, and maintains transparency and adhesion to various plastic substrates. be able to. Therefore, the curable composition of the present invention can be suitably used as an adhesive for bonding a transparent plastic substrate, a material for forming a thin light guide plate used in a backlight device constituting a liquid crystal display device, and the like.

[Component (A)]
The curable composition of the present invention contains an epoxy group and a polymerizable unsaturated group-containing monomer. The said compound which has an epoxy group and a polymerizable unsaturated group has the effect | action which traps the acid in hardened | cured material. Since the acid has a function of catalyzing the hydrolysis reaction of the component (B) or a cured product thereof, trapping it causes the hydrolysis reaction of the component (B) or the cured product under high-temperature and high-humidity conditions. It can be suppressed, that is, hydrolysis resistance can be imparted, and the transparency of component (B) or a cured product thereof and the adhesion with various plastic substrates are prevented from being reduced or lost. Can do.

  Examples of the polymerizable unsaturated group include vinyl group, allyl group, methallyl group, allyloxy group, methallyloxy group, (meth) acryloyl group, (meth) acryloyloxy group and the like. In the present invention, among these, a (meth) acryloyloxy group is preferable because it is excellent in cross-linking curability. In the present specification, “(meth) acryloyloxy group” refers to an acryloyloxy group and a methacryloyloxy group.

  The epoxy group may be a group having an oxirane ring structure, such as a glycidyl group, an alicyclic epoxy group (a group composed of two adjacent carbon atoms and oxygen atoms constituting the alicyclic ring), and the like. Can be mentioned. In the present invention, among them, an alicyclic epoxy group is preferable because it is particularly excellent in the acid trap effect.

That is, as the epoxy group and polymerizable unsaturated group-containing monomer in the present invention, an alicyclic epoxy group-containing (meth) acrylate monomer represented by the following formula (a) is particularly preferable.

Ring Z in the above formula represents an alicyclic ring constituting an alicyclic epoxy group, X represents an aliphatic hydrocarbon group, or a group in which two or more aliphatic hydrocarbon groups are bonded via a linking group, R ¹ represents a hydrogen atom or a methyl group. n represents an integer of 0 or more.

  The alicyclic ring includes a monocyclic hydrocarbon ring and a polycyclic hydrocarbon ring (spiro hydrocarbon ring, ring assembly hydrocarbon ring, bridged cyclic hydrocarbon ring, condensed ring hydrocarbon ring, and bridged condensed ring ring. Including hydrocarbon rings).

  Examples of the monocyclic hydrocarbon ring include about 3 to 20 members (preferably 3 to 15 members, particularly preferably 5 to 8 members) such as cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, and cyclooctane. A cycloalkene of about 3 to 20 members (preferably 3 to 15 members, particularly preferably 5 to 8 members) such as cyclopentene and cyclohexene.

Examples of the spiro hydrocarbon ring include C _5-16 spiro hydrocarbon rings such as spiro [4.4] nonane, spiro [4.5] decane, and spirobicyclohexane.

Examples of the ring-assembled hydrocarbon ring include a ring-assembled hydrocarbon ring containing a C _5-12 cycloalkane such as _{bicyclohexane} .

Examples of the bridged cyclic hydrocarbon ring include pinane, bornane, norpinane, norbornane, norbornene, bicycloheptane, bicycloheptene, bicyclooctane (bicyclo [2.2.2] octane, bicyclo [3.2.1] octane, etc. Bicyclic hydrocarbon rings such as homobredane, adamantane, tricyclo [5.2.1.0 ^2,6 ] decane, tricyclo [4.3.1.1 ^2,5 ] undecane, etc. Ring: Tetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodecane, and tetracyclic hydrocarbon rings such as perhydro-1,4-methano-5,8-methanonaphthalene.

  Examples of the condensed cyclic hydrocarbon ring include 5 to 8 members such as perhydronaphthalene (decalin), perhydroanthracene, perhydrophenanthrene, perhydroacenaphthene, perhydrofluorene, perhydroindene, and perhydrophenalene. Mention may be made of condensed rings in which a plurality of cycloalkanes are condensed.

  Examples of the bridged condensed cyclic hydrocarbon ring include dimers of dienes (for example, dimers of cycloalkadiene such as cyclopentadiene, cyclohexadiene, cycloheptadiene), hydrogenated products thereof, and the like. it can.

  The alicyclic ring has various substituents [eg, halogen atom, oxo group, hydroxyl group, substituted oxy group (eg, alkoxy group, aryloxy group, aralkyloxy group, acyloxy group etc.), carboxyl group, substituted oxycarbonyl group. (Alkoxycarbonyl group, aryloxycarbonyl group, aralkyloxycarbonyl group, etc.), substituted or unsubstituted carbamoyl group, cyano group, nitro group, substituted or unsubstituted amino group, sulfo group, heterocyclic group, etc.] May be. The hydroxyl group and carboxyl group may be protected with a protective group commonly used in the field of organic synthesis.

  Examples of the aliphatic hydrocarbon group for X include 1 to 20 carbon atoms (preferably 1 to 10, particularly preferably 1) such as a methylene group, a methylmethylene group, a dimethylmethylene group, an ethylene group, a propylene group, and a trimethylene group. An alkylene group of about 3 to 3; an alkenylene group of about 2 to 20 carbon atoms (preferably 2 to 10, particularly preferably 2 to 4) such as vinylene group, propenylene group, 1-butenylene group; ethynylene group, propynylene group, etc. Alkynylene group having about 2 to 20 carbon atoms (preferably 2 to 10, particularly preferably 2 to 3).

  Examples of the linking group include a carbonyl group (—CO—), an ether bond (—O—), a thioether bond (—S—), an ester bond (—COO—), an amide bond (—CONH—), and a carbonate bond. (-OCOO-) etc. can be mentioned.

  n shows an integer greater than or equal to 0, for example, the integer of 0-5 is preferable.

  In the present invention, for example, 3,4-epoxycyclohexylmethyl methacrylate (trade name “Cyclomer M100”, manufactured by Daicel Corporation), epoxidized dicyclopentenyl acrylate (trade name “E-DCPA”, Daicel Corporation) (Commercially available) can be suitably used. These can be used alone or in combination of two or more.

  The content of the epoxy group and polymerizable unsaturated group-containing monomer (the total amount when containing two or more types) is, for example, about 1 to 60% by weight of the total amount (100% by weight) of the curable composition of the present invention, preferably Is 3 to 40% by weight, particularly preferably 10 to 35% by weight. When content of an epoxy group and a polymerizable unsaturated group containing monomer is less than the said range, there exists a tendency for hydrolysis resistance to fall. On the other hand, when the content of the epoxy group and polymerizable unsaturated group-containing monomer exceeds the above range, the substrate adhesion tends to be lowered.

[Component (B)]
The curable composition of the present invention may have at least one polymer selected from polyester, epoxy resin, and polyurethane, which may have a (meth) acryloyloxy group (hereinafter sometimes referred to as “polymer”). ). The polymer in the present invention is an at least one group selected from a hydroxyl group, an ester bond, and a urethane bond, which has an action of interacting with a group present on the surface of various plastic substrates to express substrate adhesion. Therefore, excellent adhesion to various plastic substrates can be imparted to the cured product of the curable composition of the present invention.

  As the polymer in the present invention, for example, at least one selected from epoxy (meth) acrylate, polyester (meth) acrylate, polyurethane (meth) acrylate, polyester, epoxy resin, and polyurethane can be preferably used.

  The epoxy (meth) acrylate, polyester (meth) acrylate, and polyurethane (meth) acrylate may contain two or more (for example, two) (meth) acryloyloxy groups in one molecule. Thus, it is preferable in that a three-dimensional network structure can be formed and a cured product having excellent toughness can be formed, and it is particularly preferable that both ends of the polymer chain contain (meth) acryloyloxy groups.

  The epoxy (meth) acrylate is produced, for example, by reacting an oxirane ring of an epoxy resin with (meth) acrylic acid or a derivative thereof (for example, (meth) acrylic acid dimer, caprolactone-modified (meth) acrylic acid, etc.). be able to. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, novolac type epoxy resin, aliphatic epoxy resin, alicyclic epoxy resin, and amine-modified epoxy resin. Can do.

  The polyester (meth) acrylate is, for example, a polyester having hydroxyl groups at both ends obtained by polycondensation of a polycarboxylic acid or anhydride and a polyhydric alcohol, or a hydroxyl group at both ends obtained by ring-opening polymerization of a lactone. It can manufacture by making (meth) acrylic acid or its derivative (s) react with the hydroxyl group of polyester which has this. Examples of the polyvalent carboxylic acid or anhydride thereof include succinic acid, adipic acid, phthalic acid, isophthalic acid, terephthalic acid, and tetrahydrophthalic acid. Examples of the polyhydric alcohol include ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, polyethylene glycol, polypropylene glycol, 1,4-dimethylolbenzene, trimethylolpropane, pentaerythritol and the like can be mentioned. Examples of the lactone include α-acetolactone, β-propiolactone, γ-butyrolactone, δ-valerolactone, and ε-caprolactone.

  The polyurethane (meth) acrylate is a (meth) acrylate compound having a urethane bond in the molecule, and can be produced, for example, by addition reaction of a polyhydric alcohol, a polyisocyanate compound, and a hydroxyl group-containing (meth) acrylate. . As said polyhydric alcohol, the same example as the compound illustrated as a raw material of the said polyester (meth) acrylate can be given. Examples of the polyisocyanate compound include tolylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, diphenylmethane diisocyanate, and the like. Furthermore, examples of the hydroxyl group-containing (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 1,4-butanediol mono (meth) acrylate, and the like. .

  The polyester is obtained, for example, by polycondensation of a polyvalent carboxylic acid or anhydride and a polyhydric alcohol, or ring-opening polymerization of a lactone. Examples of the polyvalent carboxylic acid, its anhydride, polyhydric alcohol, and lactone include the same examples as the compounds exemplified as the raw material for the polyester (meth) acrylate.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, novolac type epoxy resin, aliphatic epoxy resin, alicyclic epoxy resin, and amine-modified epoxy resin. Can do.

  The polyurethane can be produced, for example, by subjecting a polyhydric alcohol and a polyisocyanate compound to an addition reaction. Examples of the polyhydric alcohol and polyisocyanate compound include the same examples as the compounds exemplified as raw materials for the polyester (meth) acrylate and polyurethane (meth) acrylate.

  The content of component (B) (the total amount when containing two or more) is, for example, about 5 to 80% by weight, preferably 10 to 70% by weight, based on the total amount (100% by weight) of the curable composition of the present invention. Particularly preferred is 20 to 65% by weight. When content of a component (B) is less than the said range, there exists a tendency for base-material adhesiveness to fall. On the other hand, when content of a component (B) exceeds the said range, there exists a tendency for hydrolysis resistance to fall.

[Component (C)]
The curable composition of the present invention contains a radical polymerization initiator. The radical polymerization initiator includes a photo radical polymerization initiator and a thermal radical polymerization initiator. These can be used alone or in combination of two or more.

  Examples of the photo radical polymerization initiator include benzophenone, acetophenone benzyl, benzyl dimethyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, dimethoxyacetophenone, dimethoxyphenylacetophenone, diethoxyacetophenone, tetra (t-butyl). Peroxycarbonyl) benzophenone, benzyl, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone (trade name “Irgacure 184”, etc., manufactured by BASF Japan Ltd.) 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl- -Propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl-propan-1-one, phenyl glyoxylic Acid methyl ester, 2-methyl-1- [4- (methyl) phenyl] -2-morpholinopropanone-1 (manufactured by BASF Japan Ltd., trade name “Irgacure 907”, etc.), 2-methyl-1- ( 4-methylthiophenyl) -2-morpholinopropan-1-one, 2-dimethylamino-2- (4-morpholino) benzoyl-1-phenylpropane, 2-benzyl-2-dimethylamino-1- (4-morpho Linophenyl) -butanone-1,2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-mo Alkylphenone compounds such as ruphorinyl) phenyl] -1-butanone; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (manufactured by BASF Japan Ltd., trade name “DAROCUR TPO” etc.), 2,4,6- Acylphosphine oxide compounds such as trimethylbenzoyl-diphenyl-phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; diphenyl disulfite, methyl orthobenzoylbenzoate, 4-dimethylaminobenzoate Ethyl acetate (Nippon Kayaku Co., Ltd., trade name “Kayacure EPA”, etc.), 2,4-diethylthioxanthone (Nippon Kayaku Co., Ltd., trade name “Kayacure DETX”, etc.), 2-hydroxy- 2-methyl-1-phenyl-propan-1-one, Aminobenzene derivatives such as 2,4-bisdiethylaminobenzophenone, 2,2′-bis (2-chlorophenyl) -4,5,4 ′, 5′-tetraphenyl-1,2′-biimidazole (Hodogaya Chemical) Co., Ltd., trade name “B-CIM” and the like), 2,6-bis (trichloromethyl) -4- (4-methoxynaphthalen-1-yl) -1,3,5-triazine, etc. Examples thereof include halomethylated triazine compounds and halomethyloxadiazole compounds such as 2-trichloromethyl-5- (2-benzofuran-2-yl-ethenyl) -1,3,4-oxadiazole. These can be used alone or in combination of two or more.

  As said thermal radical polymerization initiator, organic peroxides can be mentioned, for example. Examples of the organic peroxides include hydroperoxide, dialkyl peroxide, peroxyester, diacyl peroxide, peroxydicarbonate, peroxyketal, and ketone peroxide (specifically, benzoyl peroxide, t-butylperoxy-2-ethylhexanoate, 2,5-dimethyl-2,5-di (2-ethylhexanoyl) peroxyhexane, t-butylperoxybenzoate, t-butylperoxide, cumene hydro Peroxide, dicumyl peroxide, di-t-butyl peroxide, 2,5-dimethyl-2,5-dibutylperoxyhexane, 2,4-dichlorobenzoyl peroxide, di-t-butylperoxydi-isopropyl Benzene, 1,1-bis (t Butylperoxy) -3,3,5-trimethylcyclohexane, methyl ethyl ketone peroxide, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate and the like). These can be used individually by 1 type or in combination of 2 or more types.

  Furthermore, together with the thermal radical polymerization initiator, naphthenic acid such as cobalt naphthenate, manganese naphthenate, zinc naphthenate, cobalt octenoate and the like, and metal salts such as cobalt, manganese, lead, zinc and vanadium of octenoic acid Can do. Similarly, tertiary amines such as dimethylaniline can be used.

  In the present invention, among them, it is preferable to use a radical photopolymerization initiator, and in particular, the combined use of two types of alkylphenone compounds and acylphosphine oxide compounds is excellent in curability and adhesion. The cured product can be obtained, and the combined ratio [the former / the latter (weight ratio)] is, for example, about 2/1 to 30/1, preferably 2/1 to 10/1, particularly preferably 2. / 1 to 5/1.

  The content of the radical polymerization initiator is, for example, about 0.1 part by weight based on 100 parts by weight of the curable compound [particularly the radically polymerizable compound such as a compound having a (meth) acryloyloxy group] contained in the curable composition of the present invention. About 5-10 weight part is preferable, More preferably, it is 1-5 weight part.

[Component (D)]
When the curable composition of the present invention further contains a polymerizable unsaturated group-containing monomer that does not contain an epoxy group, the crosslinking curability can be further improved and a cured product having higher toughness can be obtained. It is preferable in that it can be performed.

Examples of the polymerizable unsaturated group in the polymerizable unsaturated group-containing monomer that does not include the epoxy group include the same examples as the polymerizable unsaturated group in the component (A). In the present invention, a (meth) acryloyloxy group is particularly preferable, and a (meth) acrylate monomer not containing an epoxy group represented by the following formula (d) is particularly preferable. In the following formula, R ² represents a hydrocarbon group, and R ¹ represents a hydrogen atom or a methyl group as described above. m represents an integer of 1 or more.

  The hydrocarbon group includes an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, and a group in which these are bonded through a single bond or a linking group.

  Examples of the aliphatic hydrocarbon group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, an s-butyl group, a t-butyl group, a pentyl group, a hexyl group, a decyl group, and a dodecyl group. An alkyl group having 1 to 20 carbon atoms (preferably 1 to 10, particularly preferably 1 to 3 carbon atoms); 2 to 20 carbon atoms (preferably 2 to 10 carbon atoms, such as a vinyl group, an allyl group, and a 1-butenyl group) An alkenyl group having preferably about 2 to 3); an alkynyl group having about 2 to 20 carbon atoms (preferably 2 to 10, particularly preferably 2 to 3) such as an ethynyl group and a propynyl group.

  Examples of the alicyclic ring constituting the alicyclic hydrocarbon group include the same examples as the ring Z in the above formula (a).

  Examples of the aromatic hydrocarbon group include aromatic hydrocarbon groups having about 6 to 16 (preferably 6 to 14) carbon atoms such as a phenyl group, a naphthyl group, and a fluorenyl group.

  Examples of the linking group include a divalent hydrocarbon group, a carbonyl group (—CO—), an ether bond (—O—), a thioether bond (—S—), an ester bond (—COO—), an amide bond ( -CONH-), carbonate bond (-OCOO-), and a group in which a plurality of these are linked. The linking group may have a substituent such as a hydroxyl group or a carboxyl group.

  Examples of the divalent hydrocarbon group include a linear or branched alkylene group having 1 to 18 carbon atoms such as a methylene group, a methylmethylene group, a dimethylmethylene group, an ethylene group, a propylene group, and a trimethylene group, 1,2-cyclopentylene group, 1,3-cyclopentylene group, cyclopentylidene group, 1,2-cyclohexylene group, 1,3-cyclohexylene group, 1,4-cyclohexylene group, cyclohexylidene And a cycloalkylene group having 3 to 18 carbon atoms such as a group (including a cycloalkylidene group).

  The hydrocarbon group may have a substituent. Examples of the substituent include the same examples as the substituent that the ring Z in the formula (a) may have.

  m represents an integer of 1 or more, and is, for example, 1 to 10, preferably 1 to 6.

  The amount of component (D) used (the total amount when containing two or more) is, for example, about 5 to 80% by weight, preferably 5 to 60% by weight, based on the total amount (100% by weight) of the curable composition of the present invention. Particularly preferably, it is 5 to 50% by weight.

  Moreover, it is preferable that the hardened | cured material of the curable composition of this invention contains an aromatic ring at the point which can make a refractive index difference with transparent plastic base materials, such as a polycarbonate, small. Therefore, it is preferable to use a compound containing an aromatic ring as the component (B) and / or the component (D), and the total amount of the component (B) and the component (D) contained in the curable composition of the present invention. The proportion of the compound containing an aromatic ring is preferably, for example, about 20 to 99% by weight (preferably 40 to 97% by weight, particularly preferably 40 to 80% by weight).

[Component (E)]
It is preferable that the curable composition of the present invention further contains an antioxidant because a cured product having excellent transparency can be obtained.

  Examples of the antioxidant include pentaerythritol tetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate], 2,6-di-t-butyl-p-cresol. 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), 4,4′-thiobis (3-methyl-6- t-butylphenol), 2,2′-thiobis (4-methyl-6-tert-butylphenol), stearyl-β- (3,5-di-tert-butyl-4-hydroxyphenol) propionate, tetrakis [methylene-3 -(3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate] methane, triethylene glycol bis [3- (3-t- Til-4-hydroxy-5-methylphenyl) propionate], 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, 1,1 , 3-tris (2-methyl-4-hydroxy-5-t-butylphenol) butane and the like; phenyl-α-naphthylamine, phenyl-β-naphthylamine, N, N′-di-2-phenyl Amines such as -p-phenylenediamine, N-phenyl-N'-cyclohexyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine Antioxidants: dimyristyl thiodipropionate, dilauryl thiodipropionate, distearyl thiodip Sulfur-based antioxidants such as pionate; phosphorus-based antioxidants such as triisodecyl phosphite, triphenyl phosphite, 2,2-methylenebis (4,6-di-t-butylphenyl) octyl phosphite; Hydroquinone antioxidants such as 5-di-t-butylhydroquinone and 2,5-di-t-amylhydroquinone; quinoline oxidations such as 6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline Inhibitors; other antioxidants such as mercaptobenzimidazoles are included. These can be used individually by 1 type or in combination of 2 or more types.

  In the present invention, it is preferable to use at least one antioxidant selected from phenolic antioxidants and phosphorus antioxidants, and in particular, phenolic antioxidants and phosphorus antioxidants. It is preferable to use in combination in that a further excellent antioxidant effect can be obtained. The ratio [the former / the latter (weight ratio)] of the phenolic antioxidant and the phosphorus antioxidant is, for example, about 20/80 to 80/20, preferably 30/70 to 80/20, and more preferably 55 / 45-80 / 20.

  The amount of the antioxidant used (the total amount when containing two or more) is, for example, about 0.1 to 5% by weight, preferably 0.5 to 2% by weight, based on the total amount of the curable composition of the present invention. .

[Component (F)]
The curable composition of the present invention contains a cationic polymerization initiator (particularly, a photocationic polymerization initiator) as the component (F), so that the crosslinking curability of the curable compound can be further improved. preferable.

  The cationic photopolymerization initiator is a cationic photopolymerization initiator that generates a cationic species by light irradiation and initiates a curing reaction of the cationically curable compound. The cationic photopolymerization initiator is composed of a cation moiety that absorbs light and an anion moiety that is a source of acid generation.

  Examples of the cationic photopolymerization initiator in the present invention include diazonium salt compounds, iodonium salt compounds, sulfonium salt compounds, phosphonium salt compounds, selenium salt compounds, oxonium salt compounds, ammonium salt compounds, bromine salts. And the like, and the like.

  Among these, the use of a sulfonium salt compound is preferable in that a cured product having excellent curability can be formed. Examples of the cation moiety of the sulfonium salt compound include aryls such as (4-hydroxyphenyl) methylbenzylsulfonium ion, triphenylsulfonium ion, diphenyl [4- (phenylthio) phenyl] sulfonium ion, and tri-p-tolylsulfonium ion. Examples include sulfonium ions (particularly triarylsulfonium ions).

Examples of the anion part of the cationic photopolymerization initiator include BF ₄ ⁻ , B (C ₆ F ₅ ) ₄ ⁻ , PF ₆ ⁻ , [(Rf) _k PF _6−k ] ⁻ (Rf: 80% of hydrogen atoms) Examples thereof include an alkyl group substituted with a fluorine atom, k: an integer of 1 to 5, AsF ₆ ⁻ , SbF ₆ ⁻ , SbF ₅ OH ^{− and the} like.

  Examples of the photocationic polymerization initiator in the present invention include (4-hydroxyphenyl) methylbenzylsulfonium tetrakis (pentafluorophenyl) borate, 4- (4-biphenylylthio) phenyl-4-biphenylylphenylsulfonium tetrakis (penta Fluorophenyl) borate, diphenyl [4- (phenylthio) phenyl] sulfonium tris (pentafluoroethyl) trifluorophosphate, diphenyl [4- (phenylthio) phenyl] sulfonium tetrakis (pentafluorophenyl) borate, diphenyl [4- (phenylthio) Phenyl] sulfonium hexafluorophosphate, 4- (4-biphenylylthio) phenyl-4-biphenylylphenylsulfonium tris (pentafluoro Chill) trifluorophosphate, trade names "Syracure UVI-6970", "Syracure UVI-6974", "Syracure UVI-6990", "Syracure UVI-950" (manufactured by Union Carbide, USA), "Irgacure 250", “Irgacure 261”, “Irgacure 264” (manufactured by BASF Japan Ltd.), “CG-24-61” (manufactured by Ciba Geigy), “Optomer SP-150”, “Optomer SP-151”, “Optomer SP” -170 "," Optomer SP-171 "(manufactured by ADEKA Corporation)," DAICAT II "(manufactured by Daicel Corporation)," UVAC1590 "," UVAC1591 "(manufactured by Daicel-Cytec Corporation) , "CI-2064", "CI-2 39 "," CI-2624 "," CI-2481 "," CI-2734 "," CI-2855 "," CI-2823 "," CI-2758 "," CIT-1682 "(above, Nippon Soda ( Co., Ltd.), “PI-2074” (manufactured by Rhodia, tetrakis (pentafluorophenyl) borate toluylcumyl iodonium salt), “FFC509” (manufactured by 3M), “BBI-102”, “BBI-101”, “BBI-103”, “MPI-103”, “TPS-103”, “MDS-103”, “DTS-103”, “NAT-103”, “NDS-103” (above, manufactured by Midori Chemical Co., Ltd.) ), "CD-1010", "CD-1011", "CD-1012" (above, manufactured by Sartomer, USA), "CPI-100P", "CPI-101A" Commercial products such as (San Apro Co., Ltd.) can be used. These can be used individually by 1 type or in combination of 2 or more types.

  The amount of the cationic photopolymerization initiator used is, for example, about 0.05 to 2 parts by weight, preferably 0.3 to 1 part by weight, based on 100 parts by weight of the curable compound contained in the curable composition of the present invention. is there.

[Other ingredients]
The curable composition of the present invention can appropriately contain other components as needed in addition to the above components within a range not impairing the effects of the present invention. Examples of the other components include sensitizers, light stabilizers, inorganic or organic fillers, reinforcing materials such as carbon fibers and glass fibers, lubricants, antistatic agents, silane coupling agents, antifoaming agents, and leveling agents. , Surfactants, flame retardants, ultraviolet absorbers, ion adsorbers, phosphors, release agents, and the like. The amount of these used is, for example, about 5% by weight or less of the total amount of the curable composition of the present invention.

[Curable composition]
The curable composition of the present invention can be prepared by stirring and mixing the above components while excluding bubbles under vacuum as necessary. The temperature at the time of stirring and mixing is, for example, about 20 to 50 ° C. For the stirring and mixing, a known apparatus (for example, a rotation / revolution mixer, a single-screw or multi-screw extruder, a planetary mixer, a kneader, a dissolver, etc.) can be used.

  The curable composition of the present invention obtained by the above method has a low viscosity and an excellent coating property, and its viscosity [at 25 ° C., at a shear rate of 10 (1 / s)] is, for example, about 50 to 1000 mPa · s, preferably 100. It is -700 mPa * s, Most preferably, it is 120-400 mPa * s.

  Furthermore, the curable composition of the present invention is excellent in releasability. Therefore, it can be suitably used as an imprint molding material.

The curable composition of the present invention can form a cured product by irradiation with ultraviolet rays. The ultraviolet light source may be any light source that can generate acid in the curable composition by irradiating light. For example, mercury such as UV-LED, low, medium, and high pressure mercury lamps. Lamps, mercury xenon lamps, metal halide lamps, tungsten lamps, arc lamps, excimer lamps, excimer lasers, semiconductor lasers, YAG lasers, laser systems combining lasers and nonlinear optical crystals, high-frequency induced ultraviolet generators, etc. it can. The amount of ultraviolet irradiation is such that the integrated light quantity is in the range of, for example, 400 to 2000 mJ / cm ² .

  The cured product obtained by curing the curable composition of the present invention has excellent substrate adhesion to transparent plastic substrates (particularly polycarbonate substrates and polymethylmethacrylate substrates), and adhesion tests [cross-cut method: JIS K 5600- 5-6 (ISO 2409)] is, for example, 10% or less, preferably 5% or less.

  The cured product obtained by curing the curable composition of the present invention is excellent in transparency, and the total light transmittance of the cured product having a thickness of 1 mm is, for example, 88% or more, and preferably 90% or more. In addition, the total light transmittance in the visible light wavelength range of hardened | cured material can be measured based on JISK7361-1. The turbidity is, for example, 1% or less, preferably 0.5% or less, particularly preferably 0.2% or less. The turbidity can be measured according to JIS K7136.

  The refractive index (at 25 ° C., at a wavelength of 589.3 nm) of the cured product obtained by curing the curable composition of the present invention is, for example, 1.50 or more, preferably 1.54 or more. The upper limit of the refractive index is, for example, about 1.63, preferably 1.60.

  Furthermore, the cured product obtained by curing the curable composition of the present invention is excellent in hydrolysis resistance and can prevent hydrolysis of the cured product even when exposed to high temperature and high humidity for a long time. Excellent substrate adhesion and transparency can be maintained. For example, peeling in the adhesion test [cross-cut method: JIS K 5600-5-6 (ISO 2409)] of a cured product after being exposed to a condition of 60 ° C. and 90% humidity for 100 hours is, for example, 10 % Or less (preferably 5% or less). The total light transmittance is, for example, 88% or more, preferably 90% or more, and the turbidity is, for example, 2% or less, preferably 1% or less, particularly preferably 0.8% or less.

  Since the curable composition of the present invention has the above properties, an adhesive [for example, an adhesive, a polarizer, and a protective film when a thin light guide plate is formed on a transparent plastic substrate by bonding a thin film layer having unevenness on the surface thereof. Transparent plastic substrate (for example, polycarbonate substrate, polymethyl methacrylate, etc.) that constitutes an optical member, such as an adhesive for adhering a film, an adhesive for adhering a decorative plate and a touch panel or an icon sheet and a touch panel constituting a liquid crystal display An adhesive used for fixing a substrate, a polyethylene terephthalate substrate, etc.], a material of a thin light guide plate used for a backlight device constituting a liquid crystal display device, and the like can be suitably used.

  When the curable composition of the present invention is used as an adhesive, the adherend can be firmly bonded and fixed by applying it to the adherend and then applying it together and irradiating it with ultraviolet rays. The ultraviolet irradiation conditions are the same as above.

  As a method of forming a light guide plate using the curable composition of the present invention, for example, a coating film is obtained by applying the curable composition of the present invention to the surface of a transparent plastic substrate to form a coating film. And a method of producing a light guide plate having a structure in which a concavo-convex shape is formed by imprint molding and then cured, and a layer having a concavo-convex shape is laminated on the surface of a transparent plastic substrate. In addition, the coating film of the curable composition of the present invention is formed by, for example, coating on release paper or the like other than the method of directly coating and forming on the surface of the transparent plastic substrate. It can also be formed by a method of bonding to the surface. In addition, the uneven shape in the present invention is not particularly limited as long as the shape capable of exhibiting the function of irregularly reflecting light, and the arrangement of the uneven shape may be random or regular.

  The coating film can be formed, for example, by spin coating, squeegee coating, screen coating, ink jet coating, or the like.

  The thickness of the coating film is, for example, about 10 to 200 μm.

  Curing after imprint formation can be performed by irradiating with ultraviolet rays. The ultraviolet irradiation conditions are the same as above.

  The curable composition of the present invention has a low viscosity, an excellent coating property, and an excellent releasability. Therefore, if the curable composition of the present invention is used, a coating film having an extremely thin irregular shape can be easily formed by imprint molding, and the light guide plate can be further thinned. Further, the light guide plate of the present invention in which a layer having a concavo-convex shape obtained by using the curable composition of the present invention is attached to the surface of a transparent plastic substrate, the adhesion between the transparent plastic substrate and the concavo-convex layer, And excellent transparency. In addition, the difference in refractive index between the transparent plastic substrate and the layer having an uneven shape is small, and the light extraction efficiency is excellent. Furthermore, it is excellent in hydrolysis resistance and can maintain the adhesion and transparency even when exposed to high temperature and humidity for a long time. Therefore, a liquid crystal display device provided with a light guide plate obtained by using the curable composition of the present invention has high luminance and excellent visibility, and can maintain reliability even in a high temperature and high humidity environment. Moreover, it can respond to thickness reduction and weight reduction.

  EXAMPLES Hereinafter, although an Example demonstrates this invention more concretely, this invention is not limited by these Examples.

Examples 1-7, Comparative Examples 1-4
Each component was blended (unit: part by weight) according to the formulation shown in Table 1 below, and stirred and mixed at room temperature with a rotation / revolution mixer to obtain a uniform and transparent curable composition. The viscosity [at 25 ° C., shear rate 10 (1 / s)] of the curable composition obtained in Example 1 was 180 mPa · s. The refractive index of the cured product of the curable composition obtained in Example 1 was 1.56.
The substrate adhesiveness, transparency, and hydrolysis resistance of the obtained curable composition were evaluated by the following methods.

[Evaluation of substrate adhesion and hydrolysis resistance]
The curable compositions obtained in Examples and Comparative Examples were applied on a polycarbonate (PC) substrate having a size of 3 cm × 4 cm, pressed against a glass plate having a thickness of 1 mm on which a release agent was previously deposited, and made of silicon. Molded to a thickness of 70 μm using a spacer, and irradiated with UV (UV irradiation device: 365 nm LED UNIT, trade name “SSLS-U365W-011”, manufactured by USHIO INC., Irradiation intensity: 50 to 200 mW / cm, integration Light amount: 400 to 2000 mJ / cm ² ), a cured product / polycarbonate substrate laminate was obtained.
About the obtained laminated body, the adhesiveness with respect to the polycarbonate substrate of hardened | cured material was evaluated by the crosscut method [JISK5600-5-6 (ISO2409)].
Specifically, a sample having 25 pieces of 2 mm square sections is prepared by placing 6 cuts in a grid pattern in the vertical and horizontal directions at intervals of 2 mm on the cured product, and cellophane tape (trade name “ Cello tape (registered trademark) No. 405 ”, manufactured by Nichiban Co., Ltd., width 24 mm), rubbed with a fingertip and bonded to the sample, and then peeled off from the substrate at an angle of 60 ° From the ratio, the adhesion to the polycarbonate substrate was evaluated according to the following criteria.
In addition, the cured product / polycarbonate substrate laminate obtained by the same method is subjected to a moisture resistance test in which the cured product / polycarbonate substrate laminate is stored for 100 hours at 60 ° C. and a humidity of 90%, and then the adhesion to the polycarbonate substrate is evaluated in the same manner as described above. did.
In addition, except for changing from a polycarbonate substrate to a polymethylmethacrylate (PMMA) substrate, the adhesion to the polymethylmethacrylate substrate was also evaluated in the same manner. Adhesion evaluation criteria ○: peeling is 5% or less △: peeling exceeds 5% , 30% or less ×: More than 30% peeling

[Transparency and hydrolysis resistance evaluation]
The curable compositions obtained in Examples and Comparative Examples were poured into a mold having a thickness of 1 mm and a size of 3 cm × 4 cm using a 1 mm thick glass plate on which a release agent was previously deposited and a silicon spacer. And then UV irradiation (UV irradiation device: 365 nm LED UNIT, trade name “SSLS-U365W-011”, manufactured by USHIO INC., Irradiation intensity: 50 to 200 mW / cm, integrated light quantity: 400 to 2000 mJ / cm ² ) and a cured product was obtained.
About the obtained hardened | cured material, turbidity (%) and total light transmittance (%) were measured using the turbidimeter (Nippon Denshoku Industries Co., Ltd. product, NDH-300A).
Further, the cured product obtained by the same method is subjected to a moisture resistance test in which the cured product is stored for 100 hours at 60 ° C. and a humidity of 90%, and then the turbidity (%) and the total light transmittance (%) by the same method. Was measured.

Each component used in the examples and comparative examples is as follows.
<Curable compound>
[Component A]
M100: 3,4-epoxycyclohexylmethyl methacrylate, manufactured by Daicel Corporation, trade name “Cyclomer M100”
E-DCPA: Epoxidized dicyclopentenyl acrylate, manufactured by Daicel Corporation, trade name “E-DCPA”
[Component B]
EBECRYL 524: Mixture of polyester and 1,6-hexanediol diacrylate [former / latter (weight ratio) = 70/30], manufactured by Daicel Ornex Co., Ltd., trade name “EBECRYL 524”
EBECRYL3708: Epoxy (meth) acrylate, manufactured by Daicel Ornex Co., Ltd., trade name “EBECRYL3708”
M-600A: 2-hydroxy-3-phenoxypropyl acrylate (manufactured by Kyoeisha Chemical Co., Ltd.), trade name “epoxy ester M-600A”
AH-600: Polyurethane (meth) acrylate, phenylglycidyl ether acrylate hexamethylene diisocyanate urethane prepolymer, manufactured by Kyoeisha Chemical Co., Ltd., trade name “AH-600”
FM2D: Polyester (meth) acrylate, unsaturated fatty acid hydroxyalkyl ester modified ε-caprolactone, manufactured by Daicel Corporation, trade name “PLAXEL FM2D”
[Component D]
A-LEN-10: Ethoxylated O-phenylphenol acrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., trade name “NK Ester A-LEN-10”
DPHA: Dipentaerythritol hexaacrylate, manufactured by Daicel Ornex Co., Ltd., trade name “DPHA”
IBOA: Isobornyl acrylate, manufactured by Daicel Ornex Co., Ltd., trade name “IBOA”
[Others]
CELLOXIDE 2021P: 3,4-epoxycyclohexylmethyl (3,4-epoxy) cyclohexanecarboxylate, manufactured by Daicel Corporation, trade name “Celoxide 2021P”
YX8000: Hydrogenated bisphenol A type epoxy resin, manufactured by Mitsubishi Chemical Corporation, trade name “YX8000”
<Polymerization initiator>
[Component (C)]
Irgacure 184: cyclohexyl phenyl ketone, manufactured by BASF Japan Ltd., trade name “Irgacure 184”
TPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, manufactured by BASF Japan Ltd., trade name “DAROCUR TPO”
[Component (F)]
f-1: Diphenyl [4- (phenylthio) phenyl] sulfonium tris (pentafluoroethyl) trifluorophosphate <Antioxidant: Component (E)>
IN1010: Pentaerythritol tetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate], manufactured by BASF Japan Ltd., trade name “Irganox 1010”
JP-360: Triphenyl phosphite, manufactured by Johoku Chemical Industry Co., Ltd., trade name “JP-360”

  The curable composition of the present invention is excellent in adhesion to various plastic substrates such as polycarbonate and polymethyl methacrylate, and can form a cured product excellent in transparency. Furthermore, the cured product of the curable composition of the present invention has excellent hydrolysis resistance, can suppress the progress of hydrolysis even under high-temperature and high-humidity conditions, and maintains transparency and adhesion to various plastic substrates. be able to. Therefore, the curable composition of the present invention can be suitably used as an adhesive for bonding a transparent plastic substrate, a material for forming a thin light guide plate used in a backlight device constituting a liquid crystal display device, and the like.

Claims (9)

A curable composition containing the following components.
Component (A): Epoxy group and polymerizable unsaturated group-containing monomer component (B): At least one polymer selected from polyester, epoxy resin, and polyurethane, which may have a (meth) acryloyloxy group Component (C): radical polymerization initiator   Furthermore, the curable composition of Claim 1 containing the polymerizable unsaturated group containing monomer which does not contain an epoxy group as a component (D).   Furthermore, the curable composition of Claim 1 or 2 which contains antioxidant as a component (E).   Furthermore, the curable composition of any one of Claims 1-3 which contains a cationic polymerization initiator as a component (F).   The adhesive agent containing the curable composition of any one of Claims 1-4.   An optical member comprising a structure in which a transparent plastic substrate is fixed by a cured product of the adhesive according to claim 5.   Hardened | cured material of the curable composition of any one of Claims 1-4.   The light-guide plate which has a structure where the layer which has an uneven | corrugated shape was laminated | stacked on the surface which consists of a hardened | cured material of the curable composition of any one of Claims 1-4 on the transparent plastic substrate surface.   A liquid crystal display device comprising the light guide plate according to claim 8.