Active energy ray curable composition and its cured product

Abstract

The present invention provides an active energy ray curable composition that yields a cured product with a high refractive index and excellent imprintability. [Solution] An active energy ray curable composition is used, comprising an active energy ray polymerizable compound (A) having polymerizable unsaturated double bonds, inorganic particles (B), and a photopolymerization initiator (C), wherein the active energy ray polymerizable compound (A) contains a monofunctional monomer (A1) and a polyfunctional monomer (A2), (A2) contains a difunctional monomer (A21) and a 3-20 functional monomer (A22), the content of the 3-20 functional monomer (A22) is 1-19% by weight based on the weight of the active energy ray polymerizable compound (A), the average particle diameter of the inorganic particles (B) based on the number of particles is 5-50 nm, and the viscosity of the active energy ray polymerizable compound (A) at 25°C is 300 mPa·s or less.

Description

[Technical Field]

[0001] This invention relates to an active energy ray curable composition and its cured product. [Background technology]

[0002] In recent years, high refractive index particles have been studied extensively as fillers for anti-reflective materials, lens materials, and high dielectric materials. In particular, high refractive index particles with an average particle size of several nanometers to tens of nanometers are widely used because they also exhibit excellent transparency. Conventionally, particles such as zirconia and titania (Patent Document 1) have been used with UV-curing resins. However, the aforementioned technology did not provide sufficient imprintability on glass, and a primer was required when imprinting on a glass substrate. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2019-6984 [Overview of the project] [Problems that the invention aims to solve]

[0004] The object of the present invention is to provide an active energy ray curable composition that yields a cured product with a high refractive index and excellent imprintability.

[0005] The inventors of this invention arrived at this present invention as a result of diligent research to solve these problems. In other words, the present invention relates to an active energy ray curable composition comprising an active energy ray polymerizable compound (A) having a polymerizable unsaturated double bond, inorganic particles (B), and a photopolymerization initiator (C), wherein the active energy ray polymerizable compound (A) contains a monofunctional monomer (A1) and a polyfunctional monomer (A2), (A2) contains a difunctional monomer (A21) and a 3-20 functional monomer (A22), the content of the 3-20 functional monomer (A22) is 1-19% by weight based on the weight of the active energy ray polymerizable compound (A), the average particle diameter of the inorganic particles (B) is 5-50 nm based on the number of particles, and the viscosity of the active energy ray polymerizable compound (A) at 25°C is 300 mPa·s or less; and a cured product of the active energy ray curable composition. [Effects of the Invention]

[0006] The present invention makes it possible to provide an active energy ray curable composition that yields a cured product with a high refractive index and excellent imprintability. [Modes for carrying out the invention]

[0007] The present invention will be described in detail below.

[0008] <Active energy ray curable composition> The active energy ray curable composition of the present invention (hereinafter also referred to as "the curable composition of the present invention") is an active energy ray curable composition comprising an active energy ray polymerizable compound (A) having a polymerizable unsaturated double bond, inorganic particles (B), and a photopolymerization initiator (C), wherein the active energy ray polymerizable compound (A) contains a monofunctional monomer (A1) and a polyfunctional monomer (A2), (A2) contains a difunctional monomer (A21) and a 3-20 functional monomer (A22), the content of the 3-20 functional monomer (A22) is 1-19% by weight based on the weight of the active energy ray polymerizable compound (A), the average particle diameter of the inorganic particles (B) based on the number of particles is 5-50 nm, and the viscosity of the active energy ray polymerizable compound (A) at 25°C is 300 mPa·s or less.

[0009] <Active energy ray polymerizable compound having a polymerizable unsaturated double bond (A)> The following describes an active energy ray polymerizable compound (A) having a polymerizable unsaturated double bond. The active energy ray polymerizable compound (A) having a polymerizable unsaturated double bond (hereinafter sometimes referred to as active energy ray polymerizable compound (A)) is a compound that hardens when exposed to active energy rays, and the active energy ray polymerizable compound (A) includes a monofunctional monomer (A1) and a polyfunctional monomer (A2). The active energy ray polymerizable compound (A) may be used alone or in combination of two or more types. Furthermore, examples of active energy rays include visible light, ultraviolet light, infrared light, X-rays, alpha rays, beta rays, gamma rays, and electron beams. Ultraviolet light refers to light rays with wavelengths of 200 nm to 410 nm. Furthermore, polymerizable unsaturated double bonds are bonds that polymerize by active energy rays, and preferred functional groups having polymerizable unsaturated double bonds include vinyl groups, allyl groups, butenyl groups, maleimide groups, nadiimide groups, and (meth)acryloyl groups, which have ethylenically unsaturated bonds. From the viewpoint of curability, vinyl groups or (meth)acryloyl groups are more preferred. In this specification, "(meth)acrylate" means "acrylate and / or methacrylate." Also, "(meth)acrylic" means "acrylic and / or methacrylic," and "(meth)acryloyl" means "acryloyl and / or methacryloyl."

[0010] Examples of monofunctional monomers (A1) include monofunctional (meth)acrylates, monofunctional urethane (meth)acrylates, monofunctional (meth)acrylamides, and monofunctional N-vinyl compounds.

[0011] Monofunctional (meth)acrylates include (meth)acrylates having a chain-like aliphatic group with 4 to 22 carbon atoms {e.g., n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.}, glycidyl (meth)acrylate, hydroxyalkyl (meth)acrylate {e.g., 2-hydroxyethyl (meth)acrylate}, {e.g., 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.}, alkoxyalkyl (meth)acrylate {e.g., 2-methoxyethyl (meth)acrylate, 2-butoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, etc.}, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, 4-nonylphenoxyethylene glycol (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate Acrylates, alicyclic skeleton-containing (meth)acrylates [e.g., alicyclic skeleton-containing (meth)acrylates with 6 to 12 carbon atoms {e.g., cyclohexyl (meth)acrylate, cyclohexylmethyl (meth)acrylate, cyclohexylethyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentanyloxyethyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, 2-acryloyloxyethylhexahydroxyl [e.g., talates], aromatic ring skeleton-containing (meth)acrylates [e.g., aromatic ring skeleton-containing (meth)acrylates with 6 to 55 carbon atoms {e.g., phenyl (meth)acrylate, benzyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxy 2-methylethyl (meth)acrylate, phenoxyethoxyethyl (meth)acrylate (phenoxydiethylene glycol (meth)acrylate), paracumylphenoxyethyl (meth)acrylate, phenoxybenzyl (meth)acrylate (m-phenoxybenzyl acrylate),Examples of mono(meth)acrylate compounds include 2-hydroxy-3-phenoxypropyl (meth)acrylate, phenylbenzyl (meth)acrylate, phenylphenoxyethyl acrylate (o-phenoxyphenylethyl acrylate), (naphthyl)methyl acrylate, 1,1-biphenyl-2-yl acrylate, and mono(meth)acrylate compounds containing a fluorene skeleton.

[0012] Examples of monofunctional urethane (meth)acrylates include reaction products of a monofunctional (meth)acrylate having a hydroxyl group (a) and an organic monoisocyanate compound (b). Examples of monofunctional (meth)acrylates (a) having a hydroxyl group include hydroxyalkyl (meth)acrylates (2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and 1,4-cyclohexanedimethanol monoacrylate, etc.). Monofunctional (meth)acrylate (a) having a hydroxyl group may be used alone or in combination of two or more types. Examples of organic monoisocyanate compounds (b) include aliphatic monoisocyanate compounds (b1), alicyclic monoisocyanate compounds (b2), and aromatic monoisocyanate compounds (b3). Examples of aliphatic monoisocyanate compounds (b1) include methyl isocyanate, ethyl isocyanate, propyl isocyanate, isopropyl isocyanate, butyl isocyanate, hexyl isocyanate, octyl isocyanate, lauryl isocyanate, tetradecyl isocyanate, hexadecyl isocyanate, and octadecyl isocyanate. Examples of alicyclic monoisocyanate compounds (b2) include cyclohexyl isocyanates. Examples of aromatic monoisocyanate compounds (b3) include phenyl isocyanate and torylene isocyanate. Organic monoisocyanate compound (b) may be used alone or in combination of two or more types.

[0013] Monofunctional urethane (meth)acrylates can be obtained by urethane reaction of a monofunctional (meth)acrylate (a) having a hydroxyl group and an organic monoisocyanate compound (b) using a known method. Alternatively, commercially available products may be used, such as Viscoat #216 [manufactured by Osaka Organic Chemical Industry Co., Ltd.], Etermer EM2080 [manufactured by Choko Material Industry Co., Ltd.], and Genomer 1122 [manufactured by RAHN].

[0014] Examples of monofunctional (meth)acrylamides include (meth)acrylamide, N-alkoxy(meth)acrylamide, N-alkyl(meth)acrylamide, N-alkoxyalkyl(meth)acrylamide, N-hydroxyalkyl(meth)acrylamide, N,N-dialkyl(meth)acrylamide, N-alkoxy-N-alkyl(meth)acrylamide, and cyclic amides having an N-(meth)acryloyl group (heterocyclic skeleton-containing N-(meth)acrylamide). N-alkoxy(meth)acrylamides include those having an alkoxy group with 1 to 6 carbon atoms, such as N-methoxy(meth)acrylamide, N-ethoxy(meth)acrylamide, N-propoxy(meth)acrylamide, and N-butoxy(meth)acrylamide. N-alkyl(meth)acrylamides include those having an alkyl group with 1 to 6 carbon atoms, such as N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, and N-butyl(meth)acrylamide. N-alkoxyalkyl(meth)acrylamides include those having an alkoxyalkyl group with 1 to 6 carbon atoms, such as Nn-butoxymethylacrylamide. Examples of the N-hydroxyalkyl (meth) acrylamide include those having a hydroxyalkyl group with 1 to 6 carbon atoms, such as N-hydroxyethyl (meth) acrylamide and the like. Examples of the N,N-dialkyl (meth) acrylamide include those having an alkyl group with 1 to 22 carbon atoms, such as N,N-dimethyl (meth) acrylamide, N,N-diethyl (meth) acrylamide, N,N-dipropyl (meth) acrylamide, N,N-diisopropyl (meth) acrylamide, N,N-dibutyl (meth) acrylamide, N,N-diisobutyl (meth) acrylamide, N,N-di-tert-butyl (meth) acrylamide, N,N-diheptyl (meth) acrylamide, N,N-dioctyl (meth) acrylamide, N,N-di-tert-octyl (meth) acrylamide, N,N-didodecyl (meth) acrylamide, and N,N-dioctadecyl (meth) acrylamide and the like. Examples of the N-alkoxy-N-alkyl (meth) acrylamide include N-n-butoxy-N-methyl (meth) acrylamide, N-methyl-N-methoxy (meth) acrylamide, N-methyl-N-ethoxy (meth) acrylamide, N-methyl-N-propoxy (meth) acrylamide, N-ethyl-N-methoxy (meth) acrylamide, N-ethyl-N-ethoxy (meth) acrylamide, N-ethyl-N-butoxy (meth) acrylamide, N-propyl-N-methoxy (meth) acrylamide, N-propyl-N-ethoxy (meth) acrylamide, N-butyl-N-methoxy (meth) acrylamide, and N-butyl-N-ethoxy (meth) acrylamide and the like. Examples of the cyclic amide having an N-(meth) acryloyl group (N-(meth) acrylamide containing a heterocyclic skeleton) include N-(meth) acryloylmorpholine, N-(meth) acryloylthiomorpholine, N-(meth) acryloylpiperidine, and N-(meth) acryloylpyrrolidine and the like.

[0015] Examples of the monofunctional N-vinyl compound include N-vinyl caprolactam, N-vinyl formamide, N-vinyl imidazole, N-vinyl acetamide, and N-vinyl compounds containing a heterocyclic skeleton (e.g., N-vinyl-2-pyrrolidone, 5-methyl-3-vinyl-2-oxazolidinone, N-vinyl carbazole, N-vinyl phthalimide, etc.).

[0016] Among the above monofunctional monomers (A1), monofunctional (meth)acrylate and monofunctional (meth)acrylamide are preferred from the viewpoints of curability, refractive index, and curing shrinkage. More preferably, it is at least one monomer selected from the group consisting of (meth)acrylate containing an alicyclic skeleton, (meth)acrylate containing an aromatic ring skeleton, and N-(meth)acrylamide containing a heterocyclic skeleton. Specifically, as the (meth)acrylate containing an alicyclic skeleton, isobornyl acrylate is preferred. As the (meth)acrylate containing an aromatic ring skeleton, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, o-phenoxyphenyl ethyl acrylate, m-phenoxybenzyl acrylate, (naphthyl)methyl acrylate, benzyl acrylate, etc. are preferred. As the N-(meth)acrylamide containing a heterocyclic skeleton, N-(meth)acryloyl morpholine, etc. are preferred. Particularly preferred is the (meth)acrylate containing an aromatic ring skeleton. Specifically, phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, o-phenoxyphenyl ethyl acrylate, m-phenoxybenzyl acrylate, (naphthyl)methyl acrylate, benzyl acrylate, etc. are preferred.

[0017] The polyfunctional monomer (A2) contains a bifunctional monomer (A21) and a 3- to 20-functional monomer (A22).

[0018] Examples of difunctional monomers (A21) include di(meth)acrylates of alkylene oxide adducts (hereinafter, alkylene oxide may be abbreviated as "AO") of aromatic ring skeleton-containing di(meth)acrylates {e.g., ethoxylated bisphenol A diacrylate, propoxylated bisphenol A diacrylate, etc., acrylic-modified bisphenoxyethanol fluorene, etc., binaphthol derivatives and naphthothiol derivatives, etc.}, monomers containing a fluorene skeleton (fluorene acrylate derivatives), monomers containing a biphenyl skeleton (4-biphenyl methyl acrylate, 1,1-biphenyl-2-yl acrylate) Examples include di(meth)acrylates (4,4'-bisacryloylmethylbiphenyl), monomers containing a diphenyl sulfide skeleton {bis(4-methacryloylthiophenyl) sulfide, 1,1'-thiobis(4-ethenylthiobenzene)}, polyalkylene glycol di(meth)acrylates (dipropylene glycol diacrylate, etc.), alicyclic skeleton-containing di(meth)acrylates {e.g., dimethylol-tricyclodecane di(meth)acrylate, bis(vinyl sulfone)tricyclo[5.2.1.0]decane, etc.}, monomers containing a heterocyclic skeleton (dinaphthothiophene derivatives (e.g., dinaphthothiophene diacrylate), isocyanuric acid derivatives (e.g., isocyanuric acid EO-modified diacrylate), etc.), neopentyl glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and 1,9-nonanediol di(meth)acrylate. Specific examples of di(meth)acrylates of AO adducts of divalent phenol compounds include the di(meth)acrylate of the 4-mol adduct of resorcinol to ethylene oxide (hereinafter, ethylene oxide may be abbreviated as "EO"), the di(meth)acrylate of the 4-mol adduct of dihydroxynaphthalene to propylene oxide (hereinafter, propylene oxide may be abbreviated as "PO"), the di(meth)acrylate of the 4-mol adduct of bisphenol A to EO, the di(meth)acrylate of the 10-mol adduct of bisphenol A to EO, and the di(meth)acrylate of the 20-mol adduct of bisphenol A to EO.

[0019] Among the bifunctional monomers (A21), those preferred from the viewpoint of curability, refractive index and curing shrinkage are alicyclic skeleton-containing di(meth)acrylate [dimethylol-tricyclodecane di(meth)acrylate], acrylic-modified bisphenoxyethanol fluorene, 1,4-butanediol di(meth)acrylate, polyalkylene glycol di(meth)acrylate (dipropylene glycol diacrylate), monomers containing a diphenyl sulfide skeleton {bis(4-methacryloylthiophenyl) sulfide, 1,1'-thiobis(4-ethenylthiobenzene)}, di(meth)acrylate of an alkylene oxide adduct of bisphenol A (ethoxylated bisphenol A diacrylate), and monomers containing a biphenyl skeleton (4,4'-bisacryloylmethylbiphenyl).

[0020] Examples of 3-20 functional monomers (A22) include trifunctional (meth)acrylates, tetrafunctional (meth)acrylates, pentafunctional (meth)acrylates, and (meth)acrylates with 6 or more functionalities.

[0021] Examples of trifunctional (meth)acrylates include trimethylolpropane tri(meth)acrylate, tri(meth)acrylate of trimethylolpropane AO ​​adducts [such as trimethylolpropane EO6 molar adducts, EO9 molar adducts, EO15 molar adducts, EO20 molar adducts, and PO9 molar adducts], pentaerythritol tri(meth)acrylate, tri(meth)acrylate of pentaerythritol AO adducts [such as pentaerythritol EO6 molar adducts], glycerin tri(meth)acrylate, and tri(meth)acrylate of glycerin AO adducts [such as glycerin EO6 molar adducts and PO3 molar adducts].

[0022] Examples of tetrafunctional (meth)acrylates include pentaerythritol tetra(meth)acrylate, tetra(meth)acrylate of pentaerythritol AO adducts [such as pentaerythritol EO2 molar adducts, EO4 molar adducts, EO10 molar adducts, EO15 molar adducts, and EO35 molar adducts], ethoxylated pentaerythritol tetraacrylate, and tetra(meth)acrylate of ditrimethylolpropane AO ​​adducts [such as ditrimethylolpropane EO10 molar adducts].

[0023] Examples of pentafunctional (meth)acrylates include dipentaerythritol penta(meth)acrylate and penta(meth)acrylates of dipentaerythritol AO adducts [such as EO2 molar adducts, EO4 molar adducts, EO10 molar adducts, and EO15 molar adducts of dipentaerythritol].

[0024] Examples of (meth)acrylates with 6 or more functionalities include dipentaerythritol hexa(meth)acrylate, hexa(meth)acrylate of dipentaerythritol AO adducts [such as dipentaerythritol EO 2-mol adduct, EO 4-mol adduct, EO 10-mol adduct, and EO 15-mol adduct], and hexa(meth)acrylate of dipentaerythritol lactone (such as γ-butyrolactone, γ-valerolactone, and ε-caprolactone) adducts [such as dipentaerythritol ε-caprolactone 3-mol adduct, ε-caprolactone 6-mol adduct, and ε-caprolactone 12-mol adduct].

[0025] Of the 3-20 functional monomers (A22), from the viewpoint of curability, refractive index and curing shrinkage, 3-6 functional (meth)acrylates are preferred, and more preferably trimethylolpropane tri(meth)acrylate, trimethylolpropane AO ​​adduct [trimethylolpropane EO6 molar adduct, EO9 molar adduct] tri(meth)acrylate, glycerin tri(meth)acrylate and glycerin AO adduct [glycerin EO6 molar adduct and PO3 molar adduct, etc.] tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol AO adduct The additives are tetra(meth)acrylate of [2-mol EO adduct or 4-mol EO adduct of pentaerythritol], ethoxylated pentaerythritol tetraacrylate, dipentaerythritol hexa(meth)acrylate, and hexa(meth)acrylate of AO adducts of dipentaerythritol [2-mol EO adduct or 4-mol EO adduct of dipentaerythritol], and particularly preferred are trimethylolpropane tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

[0026] In the present invention, the content of the 3-20 functional monomer (A22) is 1 to 19% by weight, based on the weight of the active energy ray polymerizable compound (A). If the content of the 3-20 functional monomer (A22) is less than 1% by weight, the imprintability deteriorates. Also, if the content of the 3-20 functional monomer (A22) exceeds 19% by weight, the imprintability deteriorates.

[0027] From the viewpoint of low volatility, the active energy ray polymerizable compound (A) preferably has a low content of monomers with a chemical formula weight of 230 or less, more preferably has a low content of monomers with a chemical formula weight of 200 or less, and the content of monomers with a chemical formula weight of 200 or less is preferably 50% by weight or less, more preferably 30% by weight or less, and particularly preferably 25% by weight or less, based on the weight of the active energy ray polymerizable compound (A).

[0028] The viscosity of the active energy ray polymerizable compound (A) at 25°C is 300 mPa·s or less from the viewpoint of imprintability, preferably 1 to 200 mPa·s, and more preferably 1 to 150 mPa·s. The viscosity of the active energy ray polymerizable compound (A) at 25°C can be adjusted by the type and composition ratio of monomers constituting the active energy ray polymerizable compound (A). The method for measuring the viscosity of the active energy ray polymerizable compound (A) at 25°C is as follows: The viscosity of the active energy ray polymerizable compound (A) at 25°C is measured based solely on the composition of the active energy ray polymerizable compound (A) constituting the active energy ray curable composition, and does not depend on the inorganic particles (B), photopolymerization initiator (C), or other components.

[0029] <Method for measuring viscosity> A mixture of active energy ray polymerizable compounds (A) was temperature-controlled at 25°C for 30 minutes, and the viscosity (mPa·s) was measured using an E-type viscometer [VISCOMETER TV-25L manufactured by Toki Sangyo Co., Ltd.] under the following conditions. [Measurement conditions] Cone rotor: Standard cone rotor (1°34' × R24) Measurement temperature: 25℃ Measurement range: M Rotation speed: 50 rpm

[0030] The glass transition temperature of the cured product of the active energy ray polymerizable compound (A) is preferably 70°C or higher, more preferably 90°C or higher, even more preferably 90 to 300°C, and particularly preferably 90 to 250°C, from the viewpoint of heat resistance and adhesion. The glass transition temperature of the cured product of the active energy ray polymerizable compound (A) can be adjusted by the type and composition ratio of monomers that make up the active energy ray polymerizable compound (A). The glass transition temperature mentioned above is the temperature at which the loss tangent (tanδ) reaches its maximum value when the dynamic viscoelasticity of a polymer obtained by polymerizing an active energy ray polymerizable compound (A) by the method described below is measured by the method described below. The method for measuring the glass transition temperature of the cured product of the active energy ray polymerizable compound (A) is as follows. The glass transition temperature of the cured product of the active energy ray polymerizable compound (A) is measured based solely on the composition of the active energy ray polymerizable compound (A) constituting the active energy ray curable composition. It does not depend on the inorganic particles (B), the photopolymerization initiator (C), or other components.

[0031] <Preparation of test pieces> (1) As a photoradical polymerization initiator, 1-hydroxycyclohexylphenyl ketone [trade name "Irgacure 184", manufactured by BASF] is added at a concentration of 3% by weight relative to the active energy ray polymerizable compound (A), and the mixture is stirred until homogeneous to prepare a test piece sample. (2) Cut two 1mm thick silicone rubber sheets [product name: Silicone Rubber Sheet, manufactured by AS ONE Corporation] to 10mm wide x 150mm long and attach them to both ends of a glass plate [product name: GLASS PLATE, manufactured by AS ONE Corporation, 200mm high x 200mm wide x 5mm thick]. Place approximately 5g of the prepared test piece sample between the silicone rubber sheets, cover with a PET film [product name: Lumirror S, manufactured by Toray Industries, Inc.] to prevent air from entering, and then cover with the glass plate. (3)(2) is subjected to an illuminance of 1500 mW / cm² in a 25°C environment using an ultraviolet irradiation device (e.g., Fusion UV Systems Japan VPS / I600, lamp: D bulb). 2 (UV-A) 1000 mJ / cm² 2 Irradiation, then (2) is flipped over and 1000 mJ / cm is applied from the opposite side. 2 Then harden it. (4) Cut the hardened sample from (3) into pieces with a length of 40 mm, a width of 5 mm, and a thickness of 1 mm to make test pieces.

[0032] <Method for measuring dynamic viscoelasticity> Using this test piece, measurements are taken under the following conditions using a dynamic viscoelasticity measuring device (e.g., Rheogel-E4000, manufactured by UBM). Measurement mode: Temperature-dependent, Measurement temperature range: -80℃ to 350℃, Frequency: 10Hz, Heating rate: 4℃ / min, Distortion waveform: Sine wave, Measurement fixture: Tension The glass transition temperature (Tg) is defined as the temperature at which the ratio of the loss modulus E'' to the storage modulus E' (loss tangent tanδ) of the obtained spectrum reaches its maximum value.

[0033] Methods for adjusting the glass transition temperature include, for example, using an active energy ray polymerizable compound (A) with a high glass transition temperature for homopolymers, or increasing the number of functional groups, in order to raise the glass transition temperature.

[0034] The refractive index of the active energy ray polymerizable compound (A) is preferably 1.50 or higher, more preferably 1.55 or higher, and particularly preferably 1.60 or higher, from the viewpoint of the refractive index of the cured product. However, an active energy ray polymerizable compound with a refractive index of less than 1.50 may be used in combination, as long as it does not affect the reduction in refractive index. The refractive index of the active energy ray polymerizable compound (A) was measured at 25°C using the D line of the sodium spectrum in an uncured state, in accordance with JIS-K0062:1992, using an Abbe refractometer [(DR-M2, manufactured by Atago Co., Ltd., etc.)]. The refractive index of the active energy ray polymerizable compound (A) is measured based solely on the composition of the active energy ray polymerizable compound (A) constituting the active energy ray curable composition. It does not depend on the inorganic particles (B), the photopolymerization initiator (C), or other components.

[0035] <Inorganic particles (B)> Inorganic particles (B) are described below. The inorganic particles (B) are not particularly limited as long as they are particles of an inorganic compound with an average particle size of 5 to 50 nm based on the number of particles. Examples include compounds of metallic elements and compounds of nonmetallic elements, and examples of compounds include hydrogen compounds, oxides, oxoacids, hydroxides, halides, sulfates, nitrates, carbonates, acetates, and metal complexes. Of the above inorganic compounds, from the viewpoint of refractive index, oxides of metallic elements, oxides of nonmetallic elements, and oxides containing metallic and nonmetallic elements are preferred. Inorganic particles (B) may be used individually or in combination of two or more types.

[0036] As inorganic particles (B), from the viewpoint of refractive index, at least one particle selected from the group consisting of TiO2, SiO2, SiC, BaTiO3, ZnO, MgO, SnO2, Al2O3, ZrO2, CeO2, Fe2O3, Fe3O4, WO3, Y2O3, SrTiO3, FeTiO3, MnTiO3, Nb2O5, and KTaO3 is preferred.

[0037] The average particle diameter of the inorganic particles (B) based on the number of particles is 5 to 50 nm, which is desirable because it yields a cured product with excellent dispersion stability and high light transmittance and refractive index. In this invention, the average particle diameter of the inorganic particles (B) based on the number of particles is the average primary particle diameter measured from approximately 300 particles in a photograph (25k) observed with a transmission electron microscope [JEM-F200 manufactured by JEOL Ltd.]. Here, the average primary particle diameter is the particle diameter (equivalent circle diameter) obtained by taking the diameter of a circle with an area equivalent to the area obtained from the photograph for each particle and averaging this over all measured particles. Furthermore, the average particle size of the inorganic particles (B) based on the number of particles is preferably 5 to 40 nm.

[0038] The shape of the inorganic particles (B) is not particularly limited, but may be spherical, hollow, porous, rod-shaped, plate-shaped, fibrous, or amorphous. Among these, spherical particles are preferred because they have excellent dispersion stability and yield a cured product with high light transmittance and refractive index. The crystalline structure of the inorganic particles (B) is not particularly limited, but a monoclinic crystal system is preferred because it offers excellent dispersion stability and yields a hardened product with high light transmittance and refractive index.

[0039] <Photopolymerization initiator (C)> The photopolymerization initiator (C) is described below. The photopolymerization initiator (C) can be any of the following: a photoradical polymerization initiator, a photoanionic polymerization initiator, or a photocationic polymerization initiator. Examples of photopolymerization initiators (C) include benzoin compounds (C1), alkylphenone compounds (C2), anthraquinone compounds (C3), thioxanthone compounds (C4), ketal compounds (C5), benzophenone compounds (C6), phosphine oxides (C7), and oxime ester compounds (C8).

[0040] Examples of benzoin compounds (C1) include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, and benzoin isobutyl ether. Examples of alkylphenone compounds (C2) include acetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 2-hydroxy-2-methylphenylpropan-1-one, diethoxyacetophenone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, and 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone. Examples of anthraquinone compounds (C3) include 2-ethylanthraquinone, 2-t-butylanthraquinone, 2-chloroanthraquinone, and 2-amylanthraquinone. Examples of thioxanthone compounds (C4) include 2,4-diethylthioxanthone, 2-isopropylthioxanthone, and 2-chlorothioxanthone. Examples of ketal compounds (C5) include acetophenone dimethyl ketal and benzyl dimethyl ketal. Examples of benzophenone compounds (C6) include benzophenone, 4-benzoyl-4'-methyldiphenyl sulfide, and 4,4'-bismethylaminobenzophenone. Examples of phosphine oxides (C7) include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylethylphenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide. Examples of oxime ester compounds (C8) include 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime) and ethanone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime).

[0041] Of these photopolymerization initiators (C), those preferred from the viewpoint of curability are 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylethylphenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide. The photopolymerization initiator (C) may be used alone or in combination of two or more types.

[0042] The active energy ray curable composition of the present invention preferably contains a dispersant (D) from the viewpoint of stability. The dispersant (D) is a surfactant having at least one functional group selected from the group consisting of a carboxyl group, a phosphate group, a thiol group, a hydroxyl group, and an amino group, and plays a role in adsorbing onto the surface of inorganic particles and uniformly dispersing the inorganic particles in the cured product.

[0043] Examples of surfactants having a carboxyl group include saturated fatty acids having 12 to 36 carbon atoms (such as lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, and isostearic acid) and / or salts thereof, monocarboxylic acids of alkylene oxide adducts (such as polyethylene glycol monolaurate, polyethylene glycol monostearate, and polyethylene glycol monooleate) and / or salts thereof, compounds having a (meth)acryloyloxy group or vinyl group and a carboxyl group (such as carboxyethyl (meth)acrylate, ω-carboxy-polycaprolactone mono(meth)acrylate, monohydroxyethyl (meth)acrylate phthalate, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, and 2-methacryloyloxyethyl hexahydrophthalic acid) and salts thereof, and oligomers of acrylic acid (acrylic oligomers). Examples of surfactants having a phosphate group include alkyl phosphate esters having 4 to 36 carbon atoms (such as 2-ethylhexyl acid phosphate and oleyl acid phosphate) and / or salts thereof, phosphate esters of alkylene oxide adducts (such as butoxyethyl acid phosphate) and salts thereof, compounds having a (meth)acryloyloxy group or vinyl group and a phosphate group (such as 2-methacryloyloxyethyl caproate acid phosphate, acid phosphooxypropylene glycol monomethacrylate, and 2-methacryloyloxyethyl acid phosphate (2-hydroxyethyl methacrylate acid phosphate)) and salts thereof. Examples of surfactants containing a thiol group include alkyl thiols with 8 to 36 carbon atoms (such as 1-dodecanethiol) and aromatic thiols (such as 2-mercaptobenzothiazole). Examples of surfactants having a hydroxyl group include saturated alcohols with 8 to 36 carbon atoms (octanol, decanol, octadecanol, docosanol, and triacontanol, etc.), alkylene oxide adducts of saturated alcohols with 8 to 36 carbon atoms (polyethylene glycol monolaurate, etc.), sorbitan fatty acid esters (sorbitan monostearate and sorbitan monolaurate, etc.), and compounds having a (meth)acryloyloxy group or a vinyl group and a hydroxyl group (hydroxyethyl (meth)acrylate, 4-hydroxybutyl acrylate, N-(2-hydroxyethyl)acrylamide, and 2-acryloyloxyethyl-2-hydroxyethyl-phthalic acid, etc.). Examples of surfactants having an amino group include amine compounds with 8 to 36 carbon atoms (such as N,N-dimethyldodecylamine), and compounds having a (meth)acryloyloxy group or a vinyl group and an amino group (such as 2-(dimethylamino)ethyl methacrylate and N-[3-(dimethylamino)propyl]acrylamide).

[0044] Of these dispersants (D), preferred from the viewpoint of dispersion stability are surfactants having a carboxyl group, surfactants having a phosphate group, or surfactants having a hydroxyl group, more preferably compounds having a (meth)acryloyloxy group or vinyl group and a carboxyl group, compounds having a (meth)acryloyloxy group or vinyl group and a phosphate group, compounds having a (meth)acryloyloxy group or vinyl group and a hydroxyl group, and particularly preferred carboxyethyl (meth)acrylate, ω-carboxy-polycaprolactone mono(meth)acrylate, monohydroxyethyl phthalate ( These are meth)acrylate, 2-acryloyloxyethyl succinic acid, 2-methacryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid and 2-methacryloyloxyethyl hexahydrophthalic acid, 2-methacryloyloxyethyl caproate acid phosphate, acid phosphooxypropylene glycol monomethacrylate, 2-methacryloyloxyethyl acid phosphate (2-hydroxyethyl methacrylate acid phosphate), hydroxyethyl acrylate, 4-hydroxybutyl acrylate, and N-(2-hydroxyethyl)acrylamide.

[0045] The active energy ray curable composition of the present invention can be diluted with solvent (E) as needed, within a range that does not impair the effects of the present invention. As the solvent (E), organic solvents are preferred from the viewpoint of compatibility and dispersibility with other components. Examples of such organic solvents include alcohols (methanol, ethanol, isopropanol, butanol, 3-methoxybutanol, and octanol, etc.); ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, etc.); esters (ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone, methoxybutyl acetate (3-methoxybutyl acetate), propylene glycol monomethyl ether acetate (2-methoxy-1-methylethyl acetate), and propylene glycol monoethyl ether acetate, etc.); ethers (ethylene glycol monomethyl ether, propylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol monobutyl ether, etc.); aromatic hydrocarbons (benzene, toluene, and xylene, etc.); and amides (dimethylformamide, dimethylacetamide, and N-methylpyrrolidone, etc.). Of these, methanol, isopropanol, butanol, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone, ethyl acetate, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether, methoxybutyl acetate, toluene, and xylene are preferred from the viewpoint of compatibility with the active energy ray curable composition of the present invention. The aforementioned solvent (E) may be used alone or in combination of two or more types.

[0046] The active energy ray curable composition of the present invention may contain other additives as needed, as long as they do not inhibit the effects of the present invention. Examples of additives include mold release agents, antioxidants, hindered amine-based light stabilizers, UV absorbers, antistatic agents, colorants, polymerization inhibitors, chain transfer agents, fillers, surfactants, plasticizers, dispersants, and thixotropy-imparting agents (thickeners).

[0047] Examples of mold release agents (F) include fluorine additives, acrylic leveling agents, and silicone leveling agents. Examples of fluorine additives include BM-1000, BM-1100 (manufactured by BM CHEMIE), Megafac F-142D, F-172, F-173, F-183, F-178, F-471, F-477, F-444, F-552, F-554 (manufactured by DIC Corporation), Surflon S-242, S-420, S-431, S-386, S-611, S-651, S-656, S-658, and S-693 (manufactured by AGC Seimi Chemical Co., Ltd.). Examples of acrylic leveling agents include Disparon UVX-36 [manufactured by Kusumoto Kasei Co., Ltd.]. Examples of silicone leveling agents include KP-423 [manufactured by Shin-Etsu Chemical Co., Ltd.] and Polyflow KL-401 [manufactured by Kyoeisha Co., Ltd.]. The mold release agent (F) may be used alone or in combination of two or more types.

[0048] The refractive index of the active energy ray curable composition of the present invention is preferably 1.60 to 1.80 from the viewpoint of improving the brightness of optical lenses.

[0049] The viscosity of the active energy ray-curable composition of the present invention at 25°C is preferably 300 mPa·s or less, from the viewpoint of the coating properties of the active energy ray-curable composition and the imprintability of the cured product. The viscosity of the active energy ray curable composition of the present invention at 25°C can be measured under the following conditions using an E-type viscometer [VISCOMETER TV-25L manufactured by Toki Sangyo Co., Ltd.]. [Measurement conditions] Cone rotor: Standard cone rotor (1°34' × R24) Measurement temperature: 25℃ Measurement range: M Rotation speed: 50 rpm

[0050] In the present invention, the weight percentage of the active energy ray polymerizable compound (A) is preferably 3% to 50% by weight, and more preferably 4% to 30% by weight, based on the total weight of the active energy ray polymerizable compound (A), inorganic particles (B), and photopolymerization initiator (C). If the weight percentage of the active energy ray polymerizable compound (A) is less than 3% by weight, the imprintability may be insufficient, and if it exceeds 50% by weight, the refractive index of the cured product may be insufficient.

[0051] In the present invention, the weight percentage of inorganic particles (B) is preferably 49% to 96% by weight, and more preferably 69% to 95% by weight, based on the total weight of the active energy ray polymerizable compound (A), inorganic particles (B), and photopolymerization initiator (C). If the weight percentage of the inorganic particles (B) is less than 49% by weight, the refractive index of the cured product may not be sufficient, and if it exceeds 96% by weight, the imprintability may not be sufficient.

[0052] In the present invention, the weight percentage of the photopolymerization initiator (C) is preferably 0.1% to 10% by weight, more preferably 1% to 5% by weight, and particularly preferably 1% to 3% by weight, based on the total weight of the active energy ray polymerizable compound (A), inorganic particles (B), and photopolymerization initiator (C).

[0053] In the present invention, the weight percentage of the dispersant (D) is preferably 1% to 20% by weight, and more preferably 1% to 10% by weight, based on the total weight of the active energy ray polymerizable compound (A) and inorganic particles (B).

[0054] The weight percentage of the solvent (E) in the present invention is preferably 0% to 800% by weight, more preferably 0.1% to 700% by weight, and particularly preferably 1% to 500% by weight, based on the total weight of the active energy ray polymerizable compound (A), inorganic particles (B), and photopolymerization initiator (C).

[0055] In the present invention, the weight percentage of other additives (excluding solvent (E)) is preferably 0.01% to 10% by weight, based on the total weight of the active energy ray polymerizable compound (A), inorganic particles (B), and photopolymerization initiator (C), from the viewpoint of the refractive index of the cured product.

[0056] The active energy ray curable composition of the present invention can be produced, for example, by uniformly mixing the active energy ray polymerizable compound (A), inorganic particles (B), a photopolymerization initiator (C), a dispersant (D), a solvent (E), and other additives using a known mechanical mixing method (such as a mechanical stirrer or a magnetic stirrer). The inorganic particles (B) may be dispersed in an organic solvent (such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and propylene glycol monomethyl ether acetate). In this case, a mixture of the active energy ray curable composition of the present invention and the organic solvent is obtained. Furthermore, in order to achieve a desirable weight ratio of the organic solvent, the organic solvent may be removed by distillation under reduced pressure.

[0057] <Cured product> The cured product of the present invention is obtained by curing the active energy ray curable composition of the present invention, for example, by curing a coating film obtained by molding the active energy ray curable composition of the present invention by irradiating it with active energy rays. Examples of active energy rays include visible light, ultraviolet light, infrared light, X-rays, alpha rays, beta rays, gamma rays, and electron beams. Ultraviolet light refers to light rays with wavelengths between 200 nm and 410 nm. The wavelength of the active energy ray is not particularly limited as long as it can cure the composition, but it is preferably 350 nm to 410 nm, and more preferably 385 nm to 405 nm. One example of an active energy ray is light with a wavelength of 395 nm. The irradiation intensity of the active energy rays is not particularly limited as long as it can cure the composition, but is 20 mW / cm². 2 ~20,000 mW / cm² 2 It is preferable that this be the case. The integrated exposure dose of active energy rays is 100 mJ / cm². 2 ~30000 mJ / cm 2 This is preferable. The irradiation time can be determined according to the irradiation intensity.

[0058] When using ultraviolet light as the active energy ray, in addition to high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps and high-power metal halide lamps can be used as light sources (Latest Trends in UV / EB Curing Technology, edited by Radtech Research Group, CMC Publishing, p. 138, 2006), and LEDs. Among these, LEDs consume less power and generate less ozone compared to other light sources, resulting in lower running costs and a lower environmental impact. When curing with an LED light source, an LED light source ultraviolet irradiation device [for example, LED light source ultraviolet irradiation device "FJ100" 150 x 20 365, manufactured by phoseon TECHNOLOGY Co., Ltd.] can be used.

[0059] The shape of the area irradiated with the active energy rays can be either an area type with a certain surface area or a line type. In the case of a line type, the entire coating can be irradiated with light by moving the coating relative to the light source, or by moving the light source relative to the coating. In the case of a line type, the irradiation time is easy to adjust, making it easy to adjust the cumulative exposure amount.

[0060] The irradiation with active energy rays may be carried out in the atmosphere. Since the composition of the present invention has good reactivity, the reaction of the composition can proceed and it can be cured even in the atmosphere. It is particularly preferable to irradiate the composition with active energy rays in a dry atmosphere and cure it. In this case, the absorption of moisture by the cured composition can be suppressed.

[0061] In this invention, the cured product may be further heated. Heating can further advance the curing process and lower the coefficient of thermal expansion of the cured product. When further heating is performed, the heating temperature is preferably 90°C or higher.

[0062] The refractive index of the cured product of the present invention is preferably 1.60 or higher, and more preferably 1.60 to 1.80, from the viewpoint of improving the brightness of optical lenses.

[0063] The active energy ray curable composition of the present invention can be cured to produce molded articles that can be suitably used as optical components (optical lenses, optical lens sheets, films, coating materials for decorative films, coating materials for optical fibers, hard coat films, anti-reflective films, etc.).

[0064] The following describes a method for producing a molded article by curing the active energy ray curable composition of the present invention. The method for manufacturing the optical component using the active energy ray-curable composition of the present invention is not particularly limited, but for example, it can be coated and molded by the following method. That is, the composition of the present invention is coated onto a transparent substrate (including a transparent film) using a bar coater or the like so that the thickness after curing is 50 nm to 150 μm, a mold is pressed onto the coating film, and the coating film is further cured by irradiating the transparent substrate with the active energy rays described below, after which it is released from the mold to obtain the optical component.

[0065] Examples of the transparent substrates (including transparent films) mentioned above include those made using glass, methyl methacrylate (co)polymer, polyethylene terephthalate, polycarbonate, polytriacetylcellulose, and polycycloolefin resins. [Examples]

[0066] The present invention will be further described below with reference to examples and comparative examples, but the present invention is not limited thereto. Hereinafter, unless otherwise specified, "parts" refers to parts by weight.

[0067] <Preparation of Activated Energy Ray Curable Compositions> (Examples 1-9 and Comparative Examples 1-3) According to the proportions (parts by weight) shown in Table 1, an active energy ray polymerizable compound (A), inorganic particles (B), a photopolymerization initiator (C), a dispersant (D), a solvent (E), and a mold release agent (F) were placed in a glass container and stirred until homogeneous to obtain the active energy ray curable compositions of Examples 1-9 and Comparative Examples 1-3.

[0068] [Table 1]

[0069] The raw materials used in Table 1 are as follows:

[0070] (A-1): Phenoxydiethylene glycol acrylate [P2H-A: Manufactured by Kyoeisha Chemical Co., Ltd., refractive index (25℃): 1.51] (A-2): o-Phenoxyphenylethyl acrylate [A-LEN-10: Manufactured by Shin-Nakamura Chemical Industry Co., Ltd., refractive index (25℃): 1.58] (A-3): m-Phenoxybenzylacrylate [POB-A: Manufactured by Kyoeisha Chemical Co., Ltd., refractive index (25℃): 1.57] (A-4): Naphthyl methyl acrylate [NMT-A: Manufactured by Kyoeisha Chemical Co., Ltd., refractive index (25℃): 1.60] (A-5): Benzyl acrylate [Viscote #160: Manufactured by Osaka Organic Chemical Industry Co., Ltd., refractive index (25℃): 1.51] (A-6): Dimethylol-tricyclodecanediaacrylate [Light Acrylate DCP-A: manufactured by Kyoeisha Co., Ltd., refractive index (25℃): 1.50] (A-7): Dimethylol-tricyclodecanedimethacrylate [DCP: Manufactured by Shin-Nakamura Chemical Industry Co., Ltd., refractive index (25℃): 1.50] (A-8): A 40:60 blend mixture of acrylic-modified bisphenoxyethanol fluorene and o-phenoxyphenylethyl acrylate [Etermer EM2206: Eternal Materials, refractive index (25°C): 1.59] (A-9): 1,4-Butanediol diacrylate [Viscote #195: Manufactured by Osaka Organic Chemical Industry Co., Ltd., refractive index (25℃): 1.46] (A-10): Dipropylene glycol diacrylate [Miramer M222: manufactured by Miwon, refractive index (25℃): 1.45] (A-11): Bis(4-methacryloylthiophenyl) sulfide [manufactured by Nacalai Tesque Co., Ltd., refractive index (25℃): 1.66] (A-12): 1,1'-Thiobis(4-ethenylthiobenzene) [Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., refractive index (25℃): 1.69] (A-13): Ethoxylated bisphenol A diacrylate [Neomer BA-641: Manufactured by Sanyo Chemical Industries, Ltd., refractive index (25℃): 1.54] (A-14): 4,4'-Bisacrylooxymethylbiphenyl [DABP: Manufactured by JFE Chemical Corporation, refractive index (25℃): 1.59] (A-15): Trimethylolpropane triacrylate [Aronics M-309: Manufactured by Toagosei Co., Ltd., refractive index (25℃): 1.48] (A-16): Pentaerythritol triacrylate [EtermerEM-235: Manufactured by Choko Materials Industry Co., Ltd., refractive index (25℃): 1.48] (A-17): Pentaerythritol tetraacrylate [Neomer EA-300: Manufactured by Sanyo Chemical Industries, Ltd., refractive index (25℃): 1.48] (A-18): Ethoxylated pentaerythritol tetraacrylate [ATM-35E: Manufactured by Shin-Nakamura Chemical Industry Co., Ltd., refractive index (25℃): 1.47] (A-19): Dipentaerythritol hexaacrylate [Neomer DA-600: Manufactured by Sanyo Chemical Industries, Ltd., refractive index (25℃): 1.47]

[0071] (B-1): Solution in which zirconium oxide particles are dispersed in methyl ethyl ketone [Product name: Zircostar AX-ZP-158-A, solid content concentration: 70% by weight, average particle size based on the number of zirconia particles: 17 nm, manufactured by Nippon Shokubai Co., Ltd.] (B-2): Titanium dioxide particles [Product name "TTO-51(C)", average particle size based on the number of titanium dioxide particles: 10-30 nm, manufactured by Ishihara Sangyo Co., Ltd.] (B-3): Solution in which barium titanate particles are dispersed in propylene glycol monomethyl ether [Product name "9714BT", solid content concentration: 15% by weight, average particle size based on the number of barium titanate particles: approximately 40 nm, manufactured by Tokushiki Co., Ltd.]

[0072] (C-1): 2,4,6-Trimethylbenzoyldiphenylphosphine oxide [Trade name "IRGACURE TPO", manufactured by BASF] (C-2): Omnirad TPO-L [2,4,6-trimethylbenzoylethylphenylphosphine oxide, manufactured by IGM Resins BV] (C-3): 1-Hydroxycyclohexylphenyl ketone [Trade name "Irgacure 184", manufactured by BASF]

[0073] (D-1): 2-Acryloyloxyethylhexahydrophthalic acid [HOA-HH: Kyoeisha Chemical Co., Ltd., HLB: 11.4] (D-2): 2-Acryloyloxyethyl succinate [HOA-MS: Kyoeisha Chemical Co., Ltd., HLB: 15.2] (D-3): Acrylic oligomer [(ACA)Z200M: Manufactured by Daicel Ornex Co., Ltd.] (D-4): Isostearic acid [manufactured by Nissan Chemical Corporation, HLB: 5.2] (D-5): 2-Methacryloyloxyethyl caproate acid phosphate [KAYAMER PM-21: Manufactured by Nippon Kayaku Co., Ltd., HLB: 5.3] (D-6): Acid phosphooxypropylene glycol monomethacrylate [Hosmer PP: manufactured by Unichemical Co., Ltd., HLB: 5.1]

[0074] (E-1): PGMEA [2-Methoxy-1-methylethyl acetate: Manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.]

[0075] (F-1): Fluorine additive [F-444: Manufactured by DIC Corporation] (F-2): Silicone surfactant [BYK-333: Manufactured by Bic Chemie Japan Co., Ltd.]

[0076] For the active energy ray curable compositions prepared in each example and comparative example, the viscosity of the active energy ray polymerizable compound (A), the glass transition temperature (Tg) of the cured product of the active energy ray polymerizable compound (A), the refractive index of the cured product of the active energy ray curable composition, the elastic deformation power, the imprintability, and the dispersion stability were evaluated using the following methods.

[0077] <Measurement of viscosity of active energy ray polymerizable compound (A)> The mixtures of the active energy ray polymerizable compounds (A) used in Examples 1-9 and Comparative Examples 1-3 were temperature-controlled at 25°C for 30 minutes, and the viscosity (mPa·s) was measured using an E-type viscometer [VISCOMETER TV-25L manufactured by Toki Sangyo Co., Ltd.] under the following conditions. In this invention, a viscosity of 300 mPa·s or less is required. [Measurement conditions] Cone rotor: Standard cone rotor (1°34' × R24) Measurement temperature: 25℃ Measurement range: M Rotation speed: 50 rpm

[0078] <Measurement of the glass transition temperature of the cured product of an active energy ray polymerizable compound (A)> (1) As a photoradical polymerization initiator, 1-hydroxycyclohexylphenyl ketone [trade name "Irgacure 184", manufactured by BASF] was added at a concentration of 3% by weight to the mixture of active energy ray polymerizable compounds (A) used in Examples 1-9 and Comparative Examples 1-3, and the mixture was stirred until homogeneous to prepare the test piece sample. (2) Cut two pieces of silicon rubber sheets with a thickness of 1 mm [Product name: Silicon Rubber Sheet, manufactured by AS ONE Corporation] into a width of 10 mm × a length of 150 mm, and attach them to both ends of a glass plate [Product name: GLASS PLATE, manufactured by AS ONE Corporation, vertical 200 mm × horizontal 200 mm × thickness 5 mm]. Place a test piece preparation sample prepared between the silicon rubber sheets with about 5 g, cover it with a PET film [Product name: Lumirror S, manufactured by Toray Industries, Inc.] so that air does not enter from above, and further cover it with a glass plate from above. (3) Under an environment of 25 °C, irradiate (2) with an ultraviolet irradiation device (VPS / I600 manufactured by Fusion UV Systems Japan, lamp: D bulb) at an illuminance of 1500 mW / cm 2 (UV-A) at 1000 mJ / cm 2 for irradiation, and further turn (2) over and cure it at 1000 mJ / cm 2 from the opposite side. (4) Cut the cured sample of (3) into a vertical width of 40 mm, a horizontal width of 5 mm, and a thickness of 1 mm to obtain a test piece. (5) Using the above test piece, measure it under the following conditions with a dynamic viscoelasticity measuring device (Rheogel-E4000, manufactured by UBM). Measurement mode: Temperature dependence, measurement temperature range: -80 °C to 350 °C, frequency: 10 Hz, heating rate: 4 °C / min, strain waveform: sine wave, measurement jig: tension The temperature at which the ratio (tanδ) of the loss elastic modulus E” to the storage elastic modulus E’ of the obtained spectrum shows the maximum value was defined as the glass transition temperature (Tg).

[0079] <Production method of cured product for refractive index and elastic deformation work rate evaluation> Drop an active energy ray curable composition onto a glass substrate [Eagle XG, manufactured by CORNING], coat it by the spin coating method at a rotation speed of 1000 rpm for 30 seconds, and then dry it at 100 °C for 3 minutes. Then, under a nitrogen atmosphere, irradiate it with ultraviolet rays at 1000 mJ / cm 2 by an ultraviolet irradiation device [VPS / I600, manufactured by Fusion UV Systems Co., Ltd.] for irradiation and curing to obtain a cured product for refractive index evaluation with a film thickness of 200 nm.

[0080] <Refractive index> The refractive index at 589 nm of the cured material prepared as described above was measured using a reflectance spectrophotometer [FE-3000, manufactured by Otsuka Electronics Co., Ltd.]. In this case, a refractive index of 1.60 or higher is considered good.

[0081] <Method for evaluating elastic deformation power> The elastic deformation power of the cured material prepared as described above was measured using a nanoindentation tester. In this case, an elastic deformation power of 10 or higher is considered good.

[0082] <Method for evaluating imprintability> (1) The active energy ray curable composition was dropped onto a glass substrate [Eagle XG, manufactured by Corning Corporation], coated by spin coating at a rotation speed of 500 rpm for 30 seconds, and then dried at 60°C for 1 minute. (2) The resin obtained in (1) was bonded onto the mold (1 μm hole shape), and a roller was rolled over it to push out the air. From the glass side, ultraviolet irradiation was applied using an ultraviolet irradiation device [model number "VPS / I600", manufactured by Fusion UV Systems Co., Ltd.] at a rate of 1000 mJ / cm². 2 It was cured by irradiation. (3) The mold from (2) was removed, and the surface of the hardened material was observed using SEM and evaluated according to the following criteria. ◎: More than 80% of the surface irregularities are transferred to the image by visual inspection. ○: Visually, 30% to less than 80% of the unevenness is transferred. ×: Only less than 30% of the surface irregularities were transferred, as observed visually.

[0083] <Method for evaluating dispersion stability> The active energy ray-curable composition was kept at 25°C for one month. The dispersion state of the particles after keeping was evaluated. If there was no visible change and the particles did not settle after one month, it was marked as "○". If the particles settled visually after one month, or if there was a clear increase in viscosity and gelation, it was marked as "×".

[0084] As can be seen from the results in Table 1, Comparative Examples 1 and 3, which used active energy ray curable compositions in which the content of 3-20 functional monomers of active energy ray polymerizable compound (A) was outside the range, showed inferior elastic deformation power and imprintability. In addition, Comparative Example 2, which used an active energy ray curable composition in which the viscosity of active energy ray polymerizable compound (A) was outside the range, showed inferior imprintability and dispersion stability. In contrast, each example yielded cured products showing good results in all aspects. [Industrial applicability]

[0085] The cured product of the active energy ray curable composition of the present invention has a high refractive index and is therefore useful as an optical component. Specifically, it is useful as an optical component such as plastic lenses (prism lenses, lenticular lenses, microlenses, Fresnel lenses, and field-of-view lenses, etc.), optical compensation films, phase difference films, prisms, optical fibers, solder resists for flexible printed wiring, plating resists, interlayer insulating films for multilayer printed wiring boards, and photosensitive optical waveguides.

Claims

1. An active energy ray curable composition comprising an active energy ray polymerizable compound (A) having a polymerizable unsaturated double bond, inorganic particles (B), and a photopolymerization initiator (C), wherein the active energy ray polymerizable compound (A) contains a monofunctional monomer (A1) and a polyfunctional monomer (A2), (A2) contains a difunctional monomer (A21) and a 3-20 functional monomer (A22), the content of the 3-20 functional monomer (A22) is 1 to 19% by weight based on the weight of the active energy ray polymerizable compound (A), the average particle diameter of the inorganic particles (B) based on the number of particles is 5 to 50 nm, and the viscosity of the active energy ray polymerizable compound (A) at 25°C is 300 mPa·s or less.

2. The inorganic particle (B) is TiO ２ , SiO ２ , SiC, BaTiO ３ , ZnO, MgO, SnO ２ , Al ２ O ３ , ZrO ２ , CeO ２ , Fe ２ O ３ , Fe ３ O ４ , WO ３ , Y ２ O ３ , SrTiO ３ , FeTiO ３ , MnTiO ３ , Nb ２ O ５ , and KTaO ３ The active energy ray-curable composition according to claim 1, which is at least one kind of particle selected from the group consisting of.

3. The active energy ray curable composition according to claim 1, wherein the glass transition temperature of the cured product of the active energy ray polymerizable compound (A) is 70°C or higher.

4. A cured product of an active energy ray curable composition according to any one of claims 1 to 3.

5. The cured product according to claim 4, wherein the refractive index is 1.60 or higher.

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