Photosensitive composition and cured product

Abstract

To provide a photosensitive composition capable of giving a cured product having a high refractive index and excellent in low thermal decomposability, low water absorbability and transparency.SOLUTION: The photosensitive composition contains metal oxide particles (A), a monomer represented by formula (1) and / or a monomer (B) represented by formula (2), an aliphatic ring-containing monomer (C) containing no aromatic ring, and a photopolymerization initiator (D).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a photosensitive composition, and more particularly to a photosensitive composition that can give a cured product having a high refractive index, low thermal decomposition, low water absorption, and excellent transparency. [Background technology]

[0002] Photosensitive compositions that can react and cure with light are being considered for use in a variety of applications, such as various optical components, such as color filters, photoresists, inks, hard coats, and optical films used in liquid crystal display devices, as well as electrical and electronic devices, and photosensitive compositions with excellent properties required for each application are being developed. In recent years, optical components, electrical and electronic devices, and the like have become smaller, thinner, and more energy-efficient, and this has led to demands for higher performance from the various components used. In order to meet such demands, various studies have been conducted on photosensitive compositions that can be used as materials for various components, etc.

[0003] Various photosensitive compositions have been proposed so far. For example, Patent Document 1 describes a polymerizable resin composition for optical films with improved brightness, which contains nanoparticles, at least one first monomer containing at least two (meth)acrylate groups, and at least one second (meth)acrylate monomer having a specific benzyloxy structure. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2012 / 158317 Summary of the Invention [Problem to be solved by the invention]

[0005] However, conventional photosensitive compositions have not been able to give cured products that are excellent in all of high refractive index, low thermal decomposition, low water absorption, and transparency.

[0006] The present disclosure has been made in consideration of the above-described current situation, and aims to provide a photosensitive composition that can give a cured product that has a high refractive index, low thermal decomposition properties, low water absorbency, and excellent transparency. [Means for solving the problem]

[0007] The present inventors have conducted extensive research into photosensitive compositions and have found that by including metal oxide particles, two specific types of monomers, and a photopolymerization initiator, a cured product with a high refractive index, low thermal decomposition properties, low water absorption, and excellent transparency can be obtained, leading to the completion of the present disclosure.

[0008] The present invention provides the following aspects. <1> A photosensitive composition comprising metal oxide particles (A), a monomer represented by the following formula (1) and / or a monomer represented by the following formula (2) (B), an aliphatic ring-containing monomer (C) that does not contain an aromatic ring, and a photopolymerization initiator (D).

[0009] [ka]

[0010] (In formula (1), R 1 represents -H, -CH or -CHOCHCH=CH. 2 are the same or different and represent a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 10 carbon atoms, a branched alkoxy group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom, an aromatic ring, or a divalent group forming a ring structure. n is an integer of 0 to 5. When n is 2 or more, R 2 may be bonded to each other to form a ring structure.

[0011] [ka]

[0012] (In formula (2), R 21 are the same or different and represent -H, -CH or -CHOCHCH=CH. 22 and R 23 are the same or different and represent a hydrogen atom or an alkyl group. a represents an integer of 0 to 6. When a is 2 or more, multiple R 22 may be the same or different. b represents an integer of 0 to 6. When b is 2 or more, multiple R 23 may be the same or different. X represents a direct bond, a divalent hydrocarbon group, -O-, -S-, -SO-, -SO2-, or a group formed by combining two or more of these. <2> The above-mentioned monomer (B) is the above-mentioned monomer having a glass transition temperature of 5°C or more and 350°C or less when made into a homopolymer. <1> The photosensitive composition according to claim 1. <3> The aliphatic ring-containing monomer (C) has a glass transition temperature of 100°C or higher and 350°C or lower when made into a homopolymer. <1> or <2> The photosensitive composition according to claim 1. <4> The content of the aliphatic ring-containing monomer (C) is 2 to 45% by mass relative to 100% by mass of the total monomer components contained in the photosensitive composition. <1> ~ <3> 1. The photosensitive composition according to any one of claims 1 to 9. <5> The metal oxide particles (A) are those containing oxide particles of at least one element selected from the group consisting of Ti, Al, Zr, In, Zn, Sn, La, Y, Ce, Mg, Ba, Ca, and Sb. <1> ~ <4> 1. The photosensitive composition according to any one of claims 1 to 9. <6> The metal oxide particles (A) have an average primary particle diameter of 1 to 50 nm. <1> ~ <5> 1. The photosensitive composition according to any one of claims 1 to 9. <7> The metal oxide particles (A) are particles that have been surface-treated with a surface treatment agent containing a phosphate ester. <1> ~ <6> 1. The photosensitive composition according to any one of claims 1 to 9. <8> The metal oxide particles (A) are particles that have been surface-treated with a surface treatment agent containing a phosphate ester compound represented by the following formula (3): <1> ~ <7> 1. The photosensitive composition according to any one of claims 1 to 9.

[0013] [ka]

[0014] (In formula (3), R 31 are the same or different and represent a linear or branched alkyl group having 1 to 10 carbon atoms. 32 are the same or different and represent a linear or branched alkylene group having 2 to 4 carbon atoms, n is an integer of 1 to 10, and a is an integer of 1 to 3. <9> The photopolymerization initiator (D) is the above-mentioned photopolymerization initiator containing at least one selected from the group consisting of acylphosphine oxide compounds and α-hydroxyketone compounds. <1> ~ <8> 1. The photosensitive composition according to any one of claims 1 to 9. <10> The above-mentioned composition has a glass transition temperature of 60°C or higher and 350°C or lower when cured. <1> ~ <9> 1. The photosensitive composition according to any one of claims 1 to 9. <11> A cured product comprising metal oxide particles (A), having structural units derived from a monomer represented by the following formula (1) and / or a monomer (B) represented by the following formula (2), and structural units derived from an aliphatic ring-containing monomer (C) that does not contain an aromatic ring, wherein the cured film has a transmittance of 93% or more at a wavelength of 410 nm when the cured film is 100 μm thick, and a glass transition temperature of 60°C or higher and 350°C or lower.

[0015] [ka]

[0016] (In formula (1), R 1 represents -H, -CH or -CHOCHCH=CH. 2are the same or different and represent a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 10 carbon atoms, a branched alkoxy group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom, an aromatic ring, or a divalent group forming a ring structure. n is an integer of 0 to 5. When n is 2 or more, R 2 may be bonded to each other to form a ring structure.

[0017] [ka]

[0018] (In formula (2), R 21 are the same or different and represent -H, -CH or -CHOCHCH=CH. 22 and R 23 are the same or different and represent a hydrogen atom or an alkyl group. a represents an integer of 0 to 6. When a is 2 or more, multiple R 22 may be the same or different. b represents an integer of 0 to 6. When b is 2 or more, multiple R 23 may be the same or different. X represents a direct bond, a divalent hydrocarbon group, -O-, -S-, -SO-, -SO2-, or a group formed by combining two or more of these. [Effects of the Invention]

[0019] The photosensitive composition of the present invention can provide a cured product having a high refractive index, low thermal decomposition property, low water absorption, and excellent transparency. The photosensitive composition of the present invention can be suitably used for optical applications such as optical members and optical adhesives. DETAILED DESCRIPTION OF THE INVENTION

[0020] The present invention will be described in detail below. A combination of two or more of the individual preferred embodiments of the present invention described below is also a preferred embodiment of the present invention. In the specification, "(meth)acrylate" means "methacrylate and / or acrylate," and "(meth)acrylic acid" means "acrylic acid and / or methacrylic acid."

[0021] 1. Photosensitive composition The photosensitive composition of the present invention is characterized by comprising metal oxide particles (A), a monomer (B) represented by the above formula (1) and / or a monomer (B) represented by the above formula (2), an aliphatic ring-containing monomer (C) that does not contain an aromatic ring, and a photopolymerization initiator (D). The reason why the photosensitive composition of the present invention provides a cured product with a high refractive index, low thermal decomposition, low water absorption, and excellent transparency is presumed to be due to the following reasons: The inclusion of metal oxide particles and the above monomer (B) having an aromatic ring structure increases the refractive index of the cured product. Furthermore, the inclusion of the above monomer (B) and the above monomer (C) increases the crosslink density and glass transition temperature, thereby reducing thermal decomposition. Furthermore, the inclusion of the above monomer (C) increases hydrophobicity and reduces water absorption. The photosensitive composition of the present invention exhibits good dispersibility of metal oxide particles, resulting in good transparency of the resulting cured product. Each component contained in the photosensitive composition will be described below.

[0022] (A) Metal oxide particles The metal oxide particles contained in the photosensitive composition are not particularly limited as long as they are particles containing a metal oxide as a main component. The metal oxide is not particularly limited, and examples thereof include oxides of one or more metal elements selected from the group consisting of elements in Groups 2 to 15 of the periodic table and elements included in the lanthanoids. Among these, oxides of at least one element selected from the group consisting of Ti, Al, Zr, In, Zn, Sn, La, Y, Ce, Mg, Ba, Ca, and Sb are preferred because of their high refractive index, more preferred are oxides of at least one element selected from the group consisting of Ti, Al, Zr, Zn, Sn, and Ce, and even more preferred are oxides of at least one element selected from the group consisting of Ti, Zr, and Zn. The metal oxide may be an oxide of a single metal, a solid solution of oxides of two or more metals, or a composite oxide.

[0023] Specific examples of the metal oxides include single metal oxides such as titanium oxide (TiO2), aluminum oxide (Al2O3), zirconium oxide (ZrO2), indium oxide (In2O3), zinc oxide (ZnO), tin oxide (SnO2), lanthanum oxide (La2O3), yttrium oxide (Y2O3), cerium oxide (CeO2), magnesium oxide (MgO), barium oxide (BaO), calcium oxide (CaO), and antimony oxide (Sb2O3); oxide solid solutions such as indium tin oxide (ITO) and antimony tin oxide (ATO); and composite oxides such as barium titanate (BaTiO3) and spinel (MgAl2O4).

[0024] The metal oxide particles may be crystalline or amorphous, but are preferably crystalline in view of the high refractive index.

[0025] The crystallinity of the metal oxide particles is preferably 50% or more, more preferably 55% or more, and even more preferably 60% or more, in terms of a high refractive index. The crystallinity can be determined by X-ray diffraction.

[0026] The crystallite diameter of the metal oxide particles is preferably 1 to 20 nm, more preferably 1 to 15 nm, and even more preferably 1 to 10 nm, in terms of high transparency. The crystallite diameter can be determined by X-ray diffraction.

[0027] The average primary particle diameter of the metal oxide particles is preferably 1 to 50 nm. When the average primary particle diameter of the metal oxide particles is within the above range, the transparency is high. The average primary particle diameter is more preferably 1 to 30 nm, and even more preferably 1 to 20 nm, at which point the transparency is higher. The average primary particle diameter is a value obtained by observing the metal oxide particles under a transmission electron microscope (TEM) at a magnification of 1,000,000 times, randomly selecting 100 particles, measuring their lengths in the major axis direction, and calculating the arithmetic average.

[0028] The shape of the metal oxide particles is not particularly limited and may be any of amorphous, granular, plate-like, columnar, needle-like, etc., but granular is preferred, and among granular, spherical is preferred. Note that the granular shape refers to a uniform shape with an aspect ratio of 1.5 or less. Regarding the shape of the metal oxide particles, when the aspect ratio is the value obtained by dividing the longest diameter by the shortest diameter within the particle, the aspect ratio is preferably 1.4 or less, more preferably 1.35 or less, and even more preferably 1.3 or less.

[0029] The metal oxide particles are preferably surface-treated with a surface treatment agent, which can improve the dispersibility of the metal oxide particles in the photosensitive composition and further increase the transparency of the resulting cured product.

[0030] The surface treatment agent is not particularly limited and may be any known surface treatment agent used to improve the dispersibility of inorganic particles, but among these, phosphate esters are preferred in terms of improving the dispersibility of the metal oxide particles. That is, the metal oxide particles are preferably surface-treated with a surface treatment agent containing a phosphate ester.

[0031] The phosphate ester is preferably a phosphate ester compound represented by the following formula (3).

[0032] [ka]

[0033] (In formula (3), R 31 are the same or different and represent a linear or branched alkyl group having 1 to 10 carbon atoms. 32 are the same or different and represent a linear or branched alkylene group having 2 to 4 carbon atoms, n is an integer of 1 to 10, and a is an integer of 1 to 3.

[0034] In the above formula (3), R 31 Examples of the linear or branched alkyl group having 1 to 10 carbon atoms represented by the formula (I) include linear alkyl groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, and n-hexyl groups, and branched alkyl groups such as isopropyl, isobutyl, sec-butyl, tert-butyl, 1-ethylpropyl, isopentyl, neopentyl, and 3-methylpentyl groups. 31 The alkyl group represented by the formula (I) is preferably a linear alkyl group, more preferably a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, or an n-hexyl group, and even more preferably a methyl group, an ethyl group, or an n-propyl group.

[0035] In the above formula (3), R 32Examples of the linear or branched alkylene group having 2 to 4 carbon atoms represented by the formula (I) include linear alkylene groups such as -C2H4-, -C3H6-, and -C4H8-, and branched alkylene groups such as -CH(CH3)-, -CH(C2H5)-, -CH(C3H6)-, -CH(CH3)2-, -CH(CH3)CH2-, -CH(C2H5)CH2-, -C(CH3)2CH2-, -CH2CH(CH3)-, -CH2CH(C2H5)-, and -CH2C(CH3)2-. Of these, -C2H4-, -C3H6-, and -C4H8- are more preferred due to their high flexibility.

[0036] In the above formula (3), n is an integer of 1 to 10, preferably 1 to 8, and more preferably 1 to 4, in terms of good compatibility with metal oxides.

[0037] In the above formula (3), a is an integer of 1 to 3, and is preferably 1 to 2 in terms of good compatibility with metal oxides.

[0038] The method for surface treating the metal oxide particles with the surface treatment agent containing the phosphate ester is not particularly limited, and may be a known method, such as mixing the metal oxide particles and the surface treatment agent in a solvent, if necessary, with heating, and then removing the solvent to obtain coated particles.

[0039] When the metal oxide particles are coated with a surface treatment agent containing the phosphate ester, the amount of the phosphate ester is preferably 5 to 30 mass %, more preferably 10 to 30 mass %, and even more preferably 13 to 30 mass %, relative to 100 mass % of the coated metal oxide particles.

[0040] The photosensitive composition may contain only one type of metal oxide particle, or may contain two or more types of metal oxide particles. The content of the metal oxide particles in the photosensitive composition is preferably 10 to 90 mass %, more preferably 30 to 90 mass %, and even more preferably 40 to 90 mass %, relative to 100 mass % of the total solid content of the photosensitive composition. In the present invention, the total amount of solids means the total amount of components that form the cured product (non-volatile components excluding solvents, curing catalysts, etc. that volatilize when the cured product is formed).

[0041] (B) A monomer represented by the above formula (1) and / or a monomer represented by the above formula (2) In this specification, the monomer represented by the above formula (1) and the monomer represented by the above formula (2) are collectively referred to as "monomer (B)". (B1) Monomer represented by the above formula (1) In the above formula (1), R 1 represents -H, -CH3 or -CH2OCH2CH=CH2. 1 is preferably —H or —CH2OCH2CH═CH2.

[0042] In the above formula (1), R 2 are the same or different and represent a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 10 carbon atoms, a branched alkoxy group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom, an aromatic ring, or a divalent group forming a ring structure.

[0043] Examples of the linear alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, and an n-decyl group.

[0044] Examples of the branched alkyl group having 3 to 10 carbon atoms include an isopropyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a 1-ethylpropyl group, an isopentyl group, a neopentyl group, a 3-methylpentyl group, an isohexyl group, and a 2-ethylhexyl group.

[0045] Examples of the linear alkenyl group having 2 to 10 carbon atoms include a vinyl group, an allyl group, a 1-propenyl group, a 2-propenyl group, a 1-butenyl group, a 2-butenyl group, and a 3-butenyl group.

[0046] Examples of the branched alkenyl group having 3 to 10 carbon atoms include a 1-methyl-1-propenyl group, a 1-methyl-2-propenyl group, a 2-methyl-1-propenyl group, and a 2-methyl-2-propenyl group.

[0047] Examples of the cycloalkyl group having 3 to 10 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, and a cyclodecyl group.

[0048] Examples of the linear alkoxy group having 1 to 10 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an n-pentyloxy group, and an n-hexyloxy group.

[0049] Examples of the branched alkoxy group having 3 to 10 carbon atoms include an isopropoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, an isopentyloxy group, a neopentyloxy group, a tert-pentyloxy group, an isohexyloxy group, a sec-hexyloxy group, and a tert-hexyloxy group.

[0050] Examples of the cyclic alkoxy group having 3 to 10 carbon atoms include a cyclopropoxy group, a cyclobutoxy group, a cyclopentyloxy group, a cyclohexyloxy group, and a cycloheptyloxy group.

[0051] Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc. Among these, an iodine atom is preferred because of its low reactivity.

[0052] The aromatic ring includes an aromatic hydrocarbon ring and an aromatic heterocyclic ring. The aromatic ring may be a monocyclic ring or a polycyclic ring, and examples of the polycyclic ring include two or more monocyclic rings or a monocyclic ring and an aliphatic ring fused or bonded together.

[0053] Examples of monocyclic aromatic hydrocarbon rings include a benzene ring. Examples of polycyclic aromatic hydrocarbon rings include fused rings such as a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a triphenylene ring, a fluorene ring, and a fluoranthene ring, and bonded rings such as a biphenyl ring, a terphenyl ring, and a binaphthalene ring.

[0054] The aromatic heterocycle is an aromatic ring containing at least one oxygen atom, sulfur atom or nitrogen atom.

[0055] Examples of monocyclic aromatic heterocycles include a furan ring, a pyran ring, a thiophene ring, a thiopyran ring, a pyrrole ring, a pyridine ring, an imidazole ring, a pyrazole ring, a pyrazine ring, a pyrimidine ring, a pyridazine ring, an oxazole ring, an isoxazole ring, a furazan ring, a thiazole ring, and an isothiazole ring.

[0056] Examples of polycyclic fused aromatic rings include a benzofuran ring, an isobenzofuran ring, a benzothiophene ring, an indole ring, an isoindole ring, a carbazole ring, a quinoline ring, a phenanthridine ring, a benzimidazole ring, a purine ring, and a phenothiazine ring.

[0057] Examples of the polycyclic linked aromatic ring include a bipyridine ring, a bithiophene ring, a phenylpyridine ring, a phenylthiophene ring, and a diphenylthiophene ring.

[0058] The number of carbon atoms in the aromatic ring is preferably 0 to 20, more preferably 2 to 15, even more preferably 3 to 12, and still more preferably 6 to 12, in terms of good curability.

[0059] Examples of the divalent group that forms the ring structure include divalent groups having a structure in which one hydrogen atom has been removed from the above-mentioned alkyl group, alkenyl group, alkoxy group, or the like, and these divalent groups can be bonded to each other to form a ring structure.

[0060] Among them, the above R 2 is preferably a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 10 carbon atoms, a branched alkoxy group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom or an aromatic ring, more preferably a cycloalkyl group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom or an aromatic ring, and even more preferably a halogen atom or an aromatic ring.

[0061] In the above formula (1), n ​​is an integer of 0 to 5. In terms of good curability, n is preferably 0 to 4, and more preferably 1 or 2.

[0062] When n is 2 or more, R 2 may be bonded to each other to form a ring structure. 2 When the monomer represented by formula (1) forms a ring structure, the monomer has a ring structure in which a benzene ring is fused with an aromatic ring or an aliphatic ring. Examples of such fused ring structures include a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a triphenylene ring, a fluorene ring, a fluoranthene ring, a benzocyclopropene ring, a benzocyclobutene ring, a benzocyclopentene ring, a benzocyclohexene ring, a benzocycloheptene ring, and a benzocyclooctene ring. Among these, in terms of low viscosity and high reactivity, a naphthalene ring, an anthracene ring, a phenanthrene ring, a perylene ring, a tetracene ring, a pyrene ring, a benzocyclopropene ring, a benzocyclobutene ring, a benzocyclopentene ring, and a benzocyclohexene ring are preferred, and a naphthalene ring, a benzocyclopropene ring, a benzocyclobutene ring, a benzocyclopentene ring, and a benzocyclohexene ring are more preferred. The number of carbon atoms in the ring structure is preferably 6 to 20, more preferably 6 to 15, and even more preferably 6 to 10, in terms of low viscosity and high reactivity.

[0063] Specific examples of the monomer (B1) represented by the above formula (1) include benzyl (meth)acrylate, o-methylbenzyl (meth)acrylate, p-methylbenzyl (meth)acrylate, m-methylbenzyl (meth)acrylate, o-hexylbenzyl (meth)acrylate, p-hexylbenzyl (meth)acrylate, m-hexylbenzyl (meth)acrylate, o-ethylbenzyl (meth)acrylate, o-ethylbenzyl (meth)acrylate, p-ethylbenzyl (meth)acrylate, m-ethylbenzyl (meth)acrylate, Acrylate, o-fluorinated benzyl (meth)acrylate, p-fluorinated benzyl (meth)acrylate, m-fluorinated benzyl (meth)acrylate, o-chlorinated benzyl (meth)acrylate, p-chlorinated benzyl (meth)acrylate, m-chlorinated benzyl (meth)acrylate, o-brominated benzyl (meth)acrylate, p-brominated benzyl (meth)acrylate, m-brominated benzyl (meth)acrylate, o-iodinated benzyl (meth)acrylate, p-iodinated benzyl (meth)acrylate, m-iodinated benzyl (meth)acrylate, 1-naphthalene (Meth)acrylic acid esters such as butylmethyl (meth)acrylate, 2-naphthylmethyl (meth)acrylate, o-biphenylmethyl (meth)acrylate, p-biphenylmethyl (meth)acrylate, m-biphenylmethyl (meth)acrylate, methyl (meth)acrylate benzocyclopropene, methyl (meth)acrylate benzocyclobutene, methyl (meth)acrylate benzocyclopentene, methyl (meth)acrylate benzocyclohexene, etc.; α-(allyloxymethyl)acrylate benzyl, α-(allyloxymethyl)acrylate o-methylbenzyl acrylate, p-methylbenzyl α-(allyloxymethyl)acrylate, m-methylbenzyl α-(allyloxymethyl)acrylate, o-benzyl fluoride α-(allyloxymethyl)acrylate, p-benzyl fluoride α-(allyloxymethyl)acrylate, m-benzyl fluoride α-(allyloxymethyl)acrylate, o-benzyl bromide α-(allyloxymethyl)acrylate, p-benzyl bromide α-(allyloxymethyl)acrylate, m-benzyl bromide α-(allyloxymethyl)acrylate,Examples of the α-(allyloxymethyl)acrylic acid esters include α-(allyloxymethyl)acrylic acid-o-benzyl chloride, α-(allyloxymethyl)acrylic acid-p-benzyl chloride, α-(allyloxymethyl)acrylic acid-m-benzyl chloride, α-(allyloxymethyl)acrylic acid-o-benzyl iodide, α-(allyloxymethyl)acrylic acid-p-benzyl iodide, α-(allyloxymethyl)acrylic acid-m-benzyl iodide, α-(allyloxymethyl)acrylic acid-1-naphthylmethyl acrylate, α-(allyloxymethyl)acrylic acid 2-naphthylmethyl acrylate, α-(allyloxymethyl)acrylic acid-o-methylbiphenyl, α-(allyloxymethyl)acrylic acid-p-methylbiphenyl, and α-(allyloxymethyl)acrylic acid-m-methylbiphenyl. Among these, benzyl (meth)acrylate, o-fluorinated benzyl (meth)acrylate, p-fluorinated benzyl (meth)acrylate, m-fluorinated benzyl (meth)acrylate, o-chlorinated benzyl (meth)acrylate, p-chlorinated benzyl (meth)acrylate, m-chlorinated benzyl (meth)acrylate, o-brominated benzyl (meth)acrylate, p-brominated benzyl (meth)acrylate, m-brominated benzyl (meth)acrylate, o-iodinated benzyl (meth)acrylate, p-iodinated benzyl (meth)acrylate, m-iodinated benzyl (meth)acrylate, 1-naphthylmethyl (meth)acrylate, 2-naphthylmethyl (meth)acrylate, and o-biphenylmethyl (meth)acrylate are particularly preferred due to their low viscosity. acrylate, p-biphenylmethyl (meth)acrylate, m-biphenylmethyl (meth)acrylate, α-(allyloxymethyl)benzyl acrylate, α-(allyloxymethyl)acrylic acid-o-benzyl fluoride, α-(allyloxymethyl)acrylic acid-p-benzyl fluoride, α-(allyloxymethyl)acrylic acid-m-benzyl fluoride, α-(allyloxymethyl)acrylic acid-o-benzyl bromide, α-(allyloxymethyl)acrylic acid-p-benzyl bromide, α-(allyloxymethyl)acrylic acid-m-benzyl bromide, α-(allyloxymethyl)acrylic acid-o-benzyl chloride, α-(allyloxymethyl)acrylic acid-p-benzyl chloride, α-(allyloxymethyl)acrylic acid-m-benzyl chloride,Preferred are α-(allyloxymethyl)acrylate-o-benzyl iodide, α-(allyloxymethyl)acrylate-p-benzyl iodide, α-(allyloxymethyl)acrylate-m-benzyl iodide, α-(allyloxymethyl)acrylate-1-naphthylmethyl acrylate, α-(allyloxymethyl)acrylate-2-naphthylmethyl acrylate, α-(allyloxymethyl)acrylate-o-methylbiphenyl, α-(allyloxymethyl)acrylate-p-methylbiphenyl, and α-(allyloxymethyl)acrylate-m-methylbiphenyl, and also benzyl (meth)acrylate, o-benzyl iodide (meth)acrylate, p-benzyl iodide (meth)acrylate, m-benzyl iodide (meth)acrylate, 1-naphthylmethyl (meth)acrylate, 2-naphthyl Methyl (meth)acrylate, o-biphenylmethyl (meth)acrylate, p-biphenylmethyl (meth)acrylate, m-biphenylmethyl (meth)acrylate, benzyl α-(allyloxymethyl)acrylate, o-benzyl α-(allyloxymethyl)acrylate, p-benzyl α-(allyloxymethyl)acrylate, m-benzyl α-(allyloxymethyl)acrylate, 1-naphthylmethyl α-(allyloxymethyl)acrylate, 2-naphthylmethyl α-(allyloxymethyl)acrylate, o-methylbiphenyl α-(allyloxymethyl)acrylate, p-methylbiphenyl α-(allyloxymethyl)acrylate, and m-methylbiphenyl α-(allyloxymethyl)acrylate are more preferred.

[0064] (B2) Monomer represented by the above formula (2) In the above formula (2), R 21 are the same or different and represent -H, -CH3, or -CH2OCH2CH=CH2.

[0065] In the above formula (2), R 22 and R 23 are the same or different and represent a hydrogen atom or an alkyl group. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 5 carbon atoms, and even more preferably 1 to 2 carbon atoms, in terms of high polarity.

[0066] In the above formula (2), a represents an integer of 0 to 6, preferably 1 to 6, and more preferably 1 to 2. When a is 2 or more, a plurality of R 22 may be the same or different.

[0067] In the above formula (2), b represents an integer of 0 to 6, preferably 1 to 6, and more preferably 1 to 2. When b is 2 or more, multiple R 23 may be the same or different.

[0068] In the formula (2), X represents a direct bond, a divalent hydrocarbon group, -O-, -S-, -SO-, -SO2-, or a group formed by combining two or more of these. Examples of the divalent hydrocarbon group include a divalent aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group.

[0069] Examples of the divalent aliphatic hydrocarbon group include linear or branched alkylene groups such as methylene, methylmethylene, dimethylmethylene, ethylene, propylene, trimethylene, and tetramethylene, and alkenylene groups such as vinylene.

[0070] Examples of the divalent alicyclic hydrocarbon group include a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, and an adamantylene group.

[0071] Examples of the divalent aromatic hydrocarbon group include a phenylene group, a tolylene group, a dimethylphenylene group, a naphthylene group, and a fluorene group.

[0072] Among these, the divalent hydrocarbon group is preferably a divalent aliphatic hydrocarbon group, and more preferably an alkylene group, because of its high glass transition temperature.

[0073] The divalent hydrocarbon group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 1 to 5 carbon atoms.

[0074] Specific examples of X include a methylene group, a methylmethylene group, a dimethylmethylene group, an ethylene group, a propylene group, a trimethylene group, a tetramethylene group, a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, an adamantylene group, a phenylene group, a tolylene group, a dimethylphenylene group, a naphthylene group, a fluorene group, etc. Among these, in terms of a high glass transition temperature, a methylene group, a methylmethylene group, a dimethylmethylene group, a cyclopropylene group, a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, an adamantylene group, a phenylene group, a tolylene group, a dimethylphenylene group, a naphthylene group, and a fluorene group are preferred, and a dimethylmethylene group, adamantylene group, a phenylene group, a tolylene group, a dimethylphenylene group, a naphthylene group, and a fluorene group are more preferred.

[0075] Specific examples of the monomer (B2) represented by the above formula (2) include, for example, di(meth)acrylate of an EO adduct of bisphenol A, di(meth)acrylate of a PO adduct of bisphenol A, an ester of two (meth)acrylic acids with a compound in which one oxyethylene group is added to each hydroxy group of bis(hydroxyphenyl)fluorene, an ester of two (meth)acrylic acids with a compound in which two oxyethylene groups are added to each hydroxy group of bis(hydroxyphenyl)fluorene, an ester of two (meth)acrylic acids with a compound in which one oxypropylene group is added to each hydroxy group of bis(hydroxyphenyl)fluorene, and an ester of two (meth)acrylic acids with a compound in which two oxypropylene groups are added to each hydroxy group of bis(hydroxyphenyl)fluorene.

[0076] The photosensitive composition may contain, as the monomer (B), either the monomer (B1) or the monomer (B2), or may contain both.

[0077] When the monomer (B) contains both the monomer (B1) and the monomer (B2), the mass ratio thereof is not particularly limited. However, in terms of a high glass transition temperature, [(B1) / (B2)] is preferably 1 / 9 to 9 / 1, more preferably 1 / 7 to 5 / 1, and even more preferably 1 / 5 to 2 / 1.

[0078] The glass transition temperature (Tg) of the above-mentioned monomer (B) when made into a homopolymer is preferably 5°C or higher and 350°C or lower, more preferably 7°C or higher and 280°C or lower, and even more preferably 10°C or higher and 250°C or lower. When the glass transition temperature of the homopolymer of the above-mentioned monomer (B) is within the above range, low thermal decomposition properties and low water absorption properties are further improved. The above-mentioned glass transition temperature is a value obtained by measuring a polymer of the above-mentioned monomer (B) with a dynamic viscoelasticity measuring device, and specifically can be determined by the method described in the examples below. When the photosensitive composition contains two or more types of the monomer (B), it is preferred that all of the monomers (B) satisfy the above-mentioned range of glass transition temperatures when made into homopolymers.

[0079] The photosensitive composition may contain only one type of the monomer (B), or may contain two or more types. The content of the monomer (B) in the photosensitive composition is preferably 3 to 50 mass%, more preferably 5 to 45 mass%, even more preferably 10 to 40 mass%, and even more preferably 15 to 35 mass%, relative to 100 mass% of the total solids content of the photosensitive composition. When the photosensitive composition contains the monomer (B1) and the monomer (B2), the content of the monomer (B) is the total amount of these.

[0080] (C) Aliphatic ring-containing monomer not containing an aromatic ring The aliphatic ring-containing monomer not containing an aromatic ring (hereinafter also referred to as monomer (C)) is a compound that contains an aliphatic ring and a group having a polymerizable double bond, but does not contain an aromatic ring. Examples of the group having a polymerizable double bond include a (meth)acryloyl group, a vinyl group, an allyl group, a methallyl group, etc. Among these, a (meth)acryloyl group is preferred because of its high reactivity.

[0081] Examples of the aliphatic ring include a cyclopropane ring, a cyclopropene ring, a cyclobutane ring, a cyclopentane ring, a cyclopentene ring, a cyclohexane ring, a cycloheptane ring, a cyclooctane ring, a bicyclo[2.1.0]pentane ring, a bicyclo[2.2.1]heptane ring (norbornane ring), a norbornene ring, a bicyclopentanyl ring, a bicyclopentenyl ring, a bicyclo[3.2.1]octane ring, a tricyclo[3.3.1 ... 3,7 ] Decane ring (adamantane ring), tricyclo[5.2.1.0 2,6 ] decane ring (tricyclodecane ring), etc.

[0082] The number of carbon atoms in the aliphatic ring is preferably 3 to 20, more preferably 4 to 15, and even more preferably 6 to 12, in terms of a high glass transition temperature.

[0083] The monomer (C) is preferably a compound represented by the following formula (4).

[0084] [ka] (In the formula, R 41 are the same or different and represent a hydrogen atom or a methyl group. 42 represents a group containing an aliphatic ring, and n represents an integer of 1 or 2.

[0085] In the above formula (4), R 41 are the same or different and represent a hydrogen atom or a methyl group.

[0086] In the above formula (4), R 42Examples of the group containing an aliphatic ring represented by the formula (I) include a monovalent or divalent alicyclic hydrocarbon group formed by removing one or two hydrogen atoms constituting the above-mentioned aliphatic ring, and a group consisting of the above-mentioned monovalent or divalent alicyclic hydrocarbon group, a monovalent or divalent aliphatic hydrocarbon group, -O-, or a combination thereof. The group containing an aliphatic ring does not contain an aromatic ring such as a benzene ring.

[0087] R 42 The number of carbon atoms in the group containing an aliphatic ring represented by the following formula is preferably 3 to 30, more preferably 4 to 25, and even more preferably 6 to 20, in terms of a high glass transition temperature.

[0088] Specific examples of the monomer (C) include cyclohexyl (meth)acrylate, cyclohexylmethyl (meth)acrylate, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentanyloxyethyl (meth)acrylate, tricyclodecanyl (meth)acrylate, and dimethylol-tricyclodecane di(meth)acrylate. , di(meth)acrylate of dimethylol-tricyclodecane EO adduct, di(meth)acrylate of dimethylol-tricyclodecane PO adduct, pentacyclopentadecanedimethanol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, norbornanedimethanol di(meth)acrylate, p-menthane-1,8-diol di(meth)acrylate, p-menthane-2,8-diol di(meth)acrylate, p-menthane-3,8-diol di(meth)acrylate, and the like. Among these, isobornyl (meth)acrylate, 1-adamantyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentanyloxyethyl (meth)acrylate, tricyclodecanyl (meth)acrylate, dimethylol-tricyclodecane di(meth)acrylate, pentacyclopentadecanedimethanol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, norbornanedimethanol di(meth)acrylate, p-menthane-1,8-diol di(meth)acrylate, p-menthane-2,8-diol di(meth)acrylate, and p-menthane-3,8-diol di(meth)acrylate are preferred because of their high glass transition temperatures.

[0089] The glass transition temperature (Tg) of the above-mentioned monomer (C) when made into a homopolymer is preferably 100°C or higher and 350°C or lower, more preferably 120°C or higher and 300°C or lower, and even more preferably 135°C or higher and 250°C or lower. When the glass transition temperature of the homopolymer of the above-mentioned monomer (B) is within the above range, low thermal decomposition properties and low water absorption properties are further improved. The above-mentioned glass transition temperature is a value obtained by measuring a polymer of the above-mentioned monomer (C) with a dynamic viscoelasticity measuring device, and specifically can be determined by the method described in the examples below. When the photosensitive composition contains two or more types of the monomer (C), it is preferred that all of the monomers (C) satisfy the above-mentioned range of glass transition temperatures when made into homopolymers.

[0090] The photosensitive composition may contain only one type of the monomer (C), or may contain two or more types. The content of the monomer (C) in the photosensitive composition is preferably 1 to 30 mass %, more preferably 2 to 25 mass %, and even more preferably 3 to 20 mass %, relative to 100 mass % of the total solid content of the photosensitive composition.

[0091] The content of the monomer (C) is preferably 2 to 45 mass %, more preferably 5 to 35 mass %, and even more preferably 10 to 35 mass %, relative to 100 mass % of the total monomer components contained in the photosensitive composition. The total monomer components are the total polymerizable monomer components contained in the photosensitive composition, and refer to the combined monomers of the monomers (B) and (C) and other polymerizable monomers polymerizable with these.

[0092] The total content of the monomer (B) and the monomer (C) is preferably 90 to 100 mass%, more preferably 93 to 100 mass%, and even more preferably 95 to 100 mass%, based on 100 mass% of the total monomer components contained in the photosensitive composition.

[0093] (D) Photopolymerization initiator The photopolymerization initiator is preferably a radical polymerizable photopolymerization initiator.Specific examples of the photopolymerization initiator include alkylphenone compounds such as 2,2-diethoxyacetophenone and 2,2-dimethoxy-2-phenylacetophenone; aminoalkylphenone compounds such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one; 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropanone, and 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methylpropanone. α-Hydroxyketone compounds such as 1-hydroxycyclohexylphenyl ketone benzophenone, 4,4'-bis(dimethylamino)benzophenone, and other benzophenone compounds; benzoin, benzoin methyl ether, and other benzoin compounds; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, ethoxyphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, ethyl(3-phenyl)phosphine oxide, benzoin, benzoin methyl ether, and other benzoin compounds; Acylphosphine oxide compounds such as benzoyl-2,4,6-trimethylbenzoyl)phenylphosphinate; thioxanthone compounds such as thioxanthone, 2-ethylthioxanthone, and 2-isopropylthioxanthone; aminobenzoate compounds such as poly(ethyl glycol) bis(p-dimethylaminobenzoate); halomethylated triazine compounds such as 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine; 2-trichloromethyl-5-(2' halomethylated oxadiazole compounds such as 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole; biimidazole compounds such as 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole; oxime ester compounds such as 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime);Examples of the initiator include titanocene compounds such as bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium; benzoate ester compounds such as p-dimethylaminobenzoic acid and p-diethylaminobenzoic acid; and azo polymerization initiators such as acridine compounds such as 9-phenylacridine. Among these, at least one compound selected from the group consisting of acylphosphine oxide compounds and α-hydroxyketone compounds is preferred, with acylphosphine oxide compounds being more preferred, in terms of the high transparency of the cured product.

[0094] The photosensitive composition may contain only one type of photopolymerization initiator (D), or may contain two or more types. The content of the photopolymerization initiator (D) in the photosensitive composition is preferably 0.05 to 5 mass %, more preferably 0.1 to 2 mass %, and even more preferably 0.1 to 1 mass %, relative to 100 mass % of the total solid content of the photosensitive composition.

[0095] (E) Other ingredients The photosensitive composition may contain other components in addition to the components described above. Examples of the other components include other monomers copolymerizable with the monomers (B) and (C), binder resins, solvents, fillers, colorants, dispersants, adhesion improvers, release agents, plasticizers, UV absorbers, antioxidants, matting agents, antifoaming agents, leveling agents, surfactants, antistatic agents, slip agents, surface modifiers, silane-based, aluminum-based, titanium-based, or other coupling agents, acid generators, and photosensitizers. These can be appropriately selected from known components and used. The amounts of these components added can also be appropriately selected with reference to known techniques.

[0096] When the photosensitive composition may contain other monomers copolymerizable with the monomers (B) and (C), the content of the other monomers is preferably 0 to 10 mass%, more preferably 0.1 to 7 mass%, and even more preferably 0.1 to 5 mass%, relative to 100 mass% of the total solid content of the photosensitive composition.

[0097] The method for preparing the photosensitive composition is not particularly limited, and any known method may be used. For example, the photosensitive composition can be prepared by mixing the above-mentioned components using a known mixer such as a blender or a mixer, a disperser, a kneader, or the like.

[0098] 2.Cured product The method for curing the photosensitive composition to obtain a cured product is not particularly limited, and examples include heating, irradiation with active energy rays, and a combination of these. The heating temperature is usually preferably 50 to 400°C, more preferably 70 to 300°C, and even more preferably 100 to 200°C. Heating may be performed at a constant temperature, or by continuously increasing the temperature at a predetermined rate and maintaining the temperature at the predetermined temperature, or by repeating the temperature increase and maintaining the temperature at the predetermined temperature two or more times.

[0099] The active energy rays may be those commonly used, including electromagnetic waves such as gamma rays, X-rays, ultraviolet rays, visible light, and infrared rays, and particle rays such as electron beams, neutron beams, and proton beams. Of these, ultraviolet rays are preferred.

[0100] The glass transition temperature (Tg) of the cured product obtained by curing the photosensitive composition is preferably 60°C or higher and 350°C or lower, in terms of good heat resistance. When the glass transition temperature of the cured product is within the above range, low thermal decomposition and low water absorption are further improved. The glass transition temperature of the cured product is more preferably 65 to 300°C, and even more preferably 70 to 300°C. The glass transition temperature can be measured using a dynamic viscoelasticity measuring device, and specifically can be determined by the method described in the examples below.

[0101] The cured product obtained by curing the photosensitive composition preferably has a transmittance of 93% or more at a wavelength of 410 nm when the cured film is 100 μm thick. When the light transmittance of the cured film is within the above range, the cured product has excellent transparency. The transmittance is more preferably 95% or more, and even more preferably 97% or more. The transmittance can be measured by the method described in the Examples below.

[0102] The cured product obtained by curing the photosensitive composition contains the metal oxide particles (A) and is also a cured product of the monomers (B) and (C), and therefore has structural units derived from the monomers (B) and (C).

[0103] The present invention also provides a cured product that contains the metal oxide particles (A), has structural units derived from the monomer represented by formula (1) and / or the monomer (B) represented by formula (2) and structural units derived from the aliphatic ring-containing monomer (C) that does not contain an aromatic ring, and has a transmittance of 93% or more at a wavelength of 410 nm when the cured film is 100 μm thick, and has a glass transition temperature of 60° C. or higher and 350° C. or lower.

[0104] 3.Applications The photosensitive composition of the present invention can provide a cured product having a high refractive index, low thermal decomposition, low water absorption, and excellent transparency. Therefore, the photosensitive composition can be suitably used in applications requiring a high refractive index, low thermal decomposition, low water absorption, or transparency. Examples of such applications include optical applications. Specific examples of applications of the photosensitive composition include hard coats, overcoats, optical films, microlenses, insulating films, adhesives, and sealants. Among these, the photosensitive composition is preferably used in hard coats, overcoats, microlenses, and adhesives. [Example]

[0105] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass."

[0106] <Examples 1 to 8 and Comparative Examples 1 to 5> Photosensitive compositions were prepared by mixing the components to obtain the formulation (solid content) shown in Table 1. The components used are as follows.

[0107] (Inorganic particle dispersion) HR-101: Zircostar (registered trademark) ZP-HR-101 (manufactured by Nippon Shokubai Co., Ltd., dispersion liquid benzyl acrylate), average primary particle size of zirconium oxide 11 nm

[0108] (aromatic monomer) BP-2EM: Light Ester BP-2EM (Kyoeisha Chemical Co., Ltd.), EO adduct dimethacrylate of bisphenol A (Tg of homopolymer: 80°C) BP-4EAL: Light Acrylate BP-4EAL (Kyoeisha Chemical Co., Ltd.), EO adduct diacrylate of bisphenol A (Tg of homopolymer: 65°C) NMTA: Light acrylate NMTA (Kyoeisha Chemical Co., Ltd.), naphthyl methyl acrylate (Tg of homopolymer: 36°C) BzA: benzyl acrylate (homopolymer Tg 7°C)

[0109] (aliphatic ring monomer) A-DCP: Light acrylate A-DCP (Kyoeisha Chemical Co., Ltd.) (Tg of homopolymer: 140°C) 513M: Fancryl 513M (manufactured by Resonac Co., Ltd.), dicyclopentanyl methacrylate (Tg of homopolymer: 175°C)

[0110] The Tg (glass transition temperature) of the homopolymer was determined by the following method. Specifically, a photopolymerization initiator (Omnirad TPO-L) was added to each monomer to a concentration of 0.1 wt% and dissolved. Kapton film was placed on a glass substrate, and double-sided tape was attached to serve as a spacer (thickness: 200 μm). The monomer in which the photopolymerization initiator had been dissolved was dripped onto the film, and the sample was sandwiched between glass substrates coated with BYK UV3500 (manufactured by BYK Chemie) to prevent air from entering, and fixed in place with clips. The sample was exposed to UV-LED irradiation (area-type irradiator manufactured by CCS Corporation) at an illuminance of 100 mW / cm. 2 , exposure amount 6J / cm 2 The film was exposed to light and cured. A strip measuring 5 mm wide and 5 cm long was cut from the cured film. Tan δ was measured using a dynamic viscoelasticity measuring device, RSA-G2 (TA Instruments Japan), with a gap of 15 mm, over a temperature range of -50°C to 250°C (heating rate of 5°C / min), a frequency of 1 Hz, and a strain of 0.1%. The temperature at which tan δ reached its maximum was defined as Tg.

[0111] (Other monomers) 2EHA: 2-ethylhexyl acrylate DPCA-120: Polyacrylate of lactone-modified polyhydric aliphatic alcohol (12 mol lactone added) (Nippon Kayaku Co., Ltd.) KAYARAD series

[0112] (Photopolymerization initiator) Omni1173: 2-hydroxy-2-methyl-1-phenylpropanone, Omnirad1173 (manufactured by IGM Resins BV), α-hydroxyketone TPO-L: Ethyl phenyl (2,4,6-trimethylbenzoyl) phosphinate, Omnirad TPO-L (manufactured by IGM Resins BV), acylphosphine oxide Omni907: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, Omnirad907 (manufactured by IGM Resins BV), α-aminoalkylphenone OXE02: Ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime), Irgacure OXE02 (BASF), N-oxime ester

[0113] The photosensitive compositions obtained in the above Examples and Comparative Examples were evaluated for glass transition temperature, refractive index, transmittance, water absorption, and thermal decomposition property by the following methods. The results are shown in Table 1.

[0114] <Refractive index> A Kapton film was placed on a glass substrate, and the photosensitive composition was applied to a film thickness of 100 μm using a bar coater (No. 50). UV-LED irradiation (area-type irradiator manufactured by CCS Corporation) was used to apply the composition at an illuminance of 100 mW / cm. 2 , exposure amount 6J / cm 2 The cured product was peeled off from the Kapton film, and the refractive index at a wavelength of 589 nm was measured using an Abbe refractometer DR-M2 (manufactured by ATAGO Corporation).

[0115] <Transmittance> The photosensitive composition was applied to a glass substrate using a bar coater (No. 50). UV-LED irradiation (area-type irradiator manufactured by CCS Corporation) was used at an illuminance of 100 mW / cm. 2 , exposure amount 6J / cm 2 The coating was exposed to light at a wavelength of 410 nm and cured to obtain a cured film with a thickness of 100 μm. Using a glass substrate as a blank, the transmittance of the cured coating was measured with a UV3100 spectrophotometer (Shimadzu Corporation) to determine the transmittance (%) at a wavelength of 410 nm.

[0116] <Glass transition temperature (Tg)> A Kapton film was placed on a glass substrate, and the photosensitive composition was applied to a film thickness of 100 μm using a bar coater (No. 50). UV-LED irradiation (area-type irradiator manufactured by CCS Corporation) was used to apply the composition to a film with an illuminance of 100 mW / cm. 2 , exposure amount 6J / cm 2The film was exposed to light and cured. A strip measuring 5 mm wide and 5 cm long was cut from the cured film. Tan δ was measured using a dynamic viscoelasticity measuring device, RSA-G2 (TA Instruments Japan), with a gap of 15 mm, over a temperature range of -50°C to 185°C (heating rate of 5°C / min), a frequency of 1 Hz, and a strain of 0.1%. The temperature at which tan δ reached its maximum was defined as Tg.

[0117] <Water absorption rate> A Kapton film was placed on a glass substrate, and the photosensitive composition was applied to a film thickness of 100 μm using a bar coater (No. 50). UV-LED irradiation (area-type irradiator manufactured by CCS Corporation) was used to apply the composition to a film with an illuminance of 100 mW / cm. 2 , exposure amount 6J / cm 2 The cured coating was then exposed to light at 1000 K and cured. A sheet measuring 2 cm in width and 2 cm in length was cut out from the cured coating. The sheet was stored for 100 hours at a temperature of 85°C and a humidity of 85% in a thermo-hygrostat PR-1K (manufactured by ESPEC).The water absorption rate was calculated from the weight difference after 100 hours. Water absorption rate (%)=((weight after 100 hours / initial weight)-1)×100

[0118] <Thermal decomposition> A Kapton film was placed on a glass substrate, and the photosensitive composition was applied to a film thickness of 100 μm using a bar coater (No. 50). UV-LED irradiation (area-type irradiator manufactured by CCS Corporation) was used to apply the composition to a film thickness of 100 mW / cm. 2 , exposure amount 6J / cm 2 The coating was then exposed to light at 100°C for 30 minutes and cured. The cured coating was then ground in a mortar to form a powder. 10 mg of the resulting powder was weighed out, and the weight loss rate (%) was measured at 200°C for 30 minutes under a nitrogen atmosphere using a TGA-50 thermogravimetric analyzer (Shimadzu).

[0119] [Table 1]

[0120] As can be seen from Table 1, a photosensitive composition containing (A) metal oxide particles, (B) a monomer represented by the above formula (1) and / or a monomer represented by the above formula (2), (C) an aliphatic ring-containing monomer that does not contain an aromatic ring, and (D) a photopolymerization initiator can give a cured product that has a high refractive index, low thermal decomposition properties, low water absorption, and excellent transparency.

Claims

1. A photosensitive composition comprising metal oxide particles (A), a monomer represented by the following formula (1) and / or a monomer represented by the following formula (2) (B), an aliphatic ring-containing monomer (C) that does not contain an aromatic ring, and a photopolymerization initiator (D): 【Chemistry 1】 (In formula (1), R １ is -H, -CH ３ or -CH ２ OCH ２ CH=CH ２ Represents R ２ are the same or different and represent a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 10 carbon atoms, a branched alkoxy group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom, an aromatic ring, or a divalent group forming a ring structure. n is an integer from 0 to 5. When n is 2 or more, R ２ may be bonded to each other to form a ring structure. 【Chemistry 2】 (In formula (2), R ２１ are the same or different and are —H, —CH ３ or -CH ２ OCH ２ CH=CH ２ Represents R ２２ and R ２３ are the same or different and represent a hydrogen atom or an alkyl group. a represents an integer of 0 to 6. When a is 2 or more, a plurality of R ２２ may be the same or different. b represents an integer of 0 to 6. When b is 2 or more, a plurality of R ２３ may be the same or different. X represents a direct bond, a divalent hydrocarbon group, —O—, —S—, —SO—, —SO ２ - or a group formed by combining two or more of these.)

2. 2. The photosensitive composition according to claim 1, wherein the monomer (B) has a glass transition temperature of 5° C. or higher and 350° C. or lower when made into a homopolymer.

3. 3. The photosensitive composition according to claim 1, wherein the aliphatic ring-containing monomer (C) has a glass transition temperature of 100° C. or higher and 350° C. or lower when made into a homopolymer.

4. 3. The photosensitive composition according to claim 1, wherein the content of the aliphatic ring-containing monomer (C) is 2 to 45% by mass relative to 100% by mass of the total monomer components contained in the photosensitive composition.

5. 3. The photosensitive composition according to claim 1, wherein the metal oxide particles (A) comprise oxide particles of at least one element selected from the group consisting of Ti, Al, Zr, In, Zn, Sn, La, Y, Ce, Mg, Ba, Ca, and Sb.

6. 3. The photosensitive composition according to claim 1, wherein the metal oxide particles (A) have an average primary particle size of 1 to 50 nm.

7. 3. The photosensitive composition according to claim 1, wherein the metal oxide particles (A) are particles whose surfaces have been treated with a surface treatment agent containing a phosphate ester.

8. 3. The photosensitive composition according to claim 1, wherein the metal oxide particles (A) are particles that have been surface-treated with a surface treatment agent containing a phosphate ester compound represented by the following formula (3): 【Transformation 3】 (In formula (3), R ３１ are the same or different and represent a linear or branched alkyl group having 1 to 10 carbon atoms. ３２ are the same or different and represent a linear or branched alkylene group having 2 to 4 carbon atoms; n is an integer of 1 to 10; and a is an integer of 1 to 3.

9. 3. The photosensitive composition according to claim 1, wherein the photopolymerization initiator (D) comprises at least one selected from the group consisting of acylphosphine oxide compounds and α-hydroxyketone compounds.

10. 3. The photosensitive composition according to claim 1, wherein the cured product has a glass transition temperature of 60° C. or higher and 350° C. or lower.

11. A cured product comprising metal oxide particles (A), having structural units derived from a monomer represented by the following formula (1) and / or a monomer (B) represented by the following formula (2), and structural units derived from an aliphatic ring-containing monomer (C) that does not contain an aromatic ring, wherein the cured film has a transmittance of 93% or more at a wavelength of 410 nm when the cured film is 100 μm thick, and a glass transition temperature of 60° C. or higher and 350° C. or lower. 【Chemistry 4】 (In formula (1), R １ is -H, -CH ３ or -CH ２ OCH ２ CH=CH ２ Represents R ２ are the same or different and represent a linear alkyl group having 1 to 10 carbon atoms, a branched alkyl group having 3 to 10 carbon atoms, a linear alkenyl group having 2 to 10 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a linear alkoxy group having 1 to 10 carbon atoms, a branched alkoxy group having 3 to 10 carbon atoms, a cyclic alkoxy group having 3 to 10 carbon atoms, a halogen atom, an aromatic ring, or a divalent group forming a ring structure. n is an integer from 0 to 5. When n is 2 or more, R ２ may be bonded to each other to form a ring structure. 【Transformation 5】 (In formula (2), R ２１ are the same or different and are —H, —CH ３ or -CH ２ OCH ２ CH=CH ２ Represents R ２２ and R ２３ are the same or different and represent a hydrogen atom or an alkyl group. a represents an integer of 0 to 6. When a is 2 or more, a plurality of R ２２ may be the same or different. b represents an integer of 0 to 6. When b is 2 or more, a plurality of R ２３ may be the same or different. X represents a direct bond, a divalent hydrocarbon group, —O—, —S—, —SO—, —SO ２ - or a group formed by combining two or more of these.)

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