Curable resin composition and its uses

Abstract

To provide a curable resin composition which can give a cured film having good compatibility and excellent substrate adhesion, a cured film formed of the curable resin composition, and a member for a display device and an optical material such as a display device which can achieve high definition by having the cured film.SOLUTION: A curable resin composition contains metal oxide particles having a number average primary particle diameter of less than 30 nm, an alkali-soluble polymer and a polymerizable monomer. Metal forming the metal oxide particles are suitably at least one selected from Ti, Al, Zr, Zn, Sn, Ce and Si, and suitably contains Zr. The metal oxide particles are suitably surface modified. A cured film is obtained by curing the curable resin composition.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a curable resin composition and uses thereof, and more preferably to a curable resin composition, a cured film, and an optical material containing metal oxide particles. [Background technology]

[0002] Curable resin compositions that can be cured by heat or active energy rays have been studied for their application to components of various display devices, such as protective films, insulating films, printed wiring boards, color filters, and spacers used in touch panel display devices, liquid crystal display devices, solid-state imaging devices, etc., and curable resin compositions have been developed according to the properties required for each application. For example, capacitive touch panel display devices generally have a transparent conductive film such as ITO formed on a substrate. The transparent conductive film is formed on the transparent conductive film, and a protective film or insulating film is further formed to protect the transparent conductive film. The protective film or insulating film is usually required to have high adhesion to the transparent conductive film, durability, and surface hardness. Furthermore, color filters are one of the main components of liquid crystal display devices, solid-state imaging devices, and the like. Color filters generally consist of a substrate, pixels, a resin black matrix (BM), and a protective film that is provided to cover and protect the pixels and resin black matrix and to flatten their irregularities. Similar to the protective film in a touch panel display device, such protective films for color filters are also required to stably exhibit sufficient surface hardness and adhesion.

[0003] In order to improve adhesion and surface hardness, which are among the required properties, curable resin compositions containing metal oxide particles such as silica fine particles are known (see, for example, Patent Document 1). Furthermore, with the trend toward higher resolution display devices, there is a demand for improved electrical properties of the interlayer insulating film sandwiched between electrodes in active matrix liquid crystal display devices, and a curable resin composition containing zirconium dioxide particles is known for obtaining an organic insulating film with a high dielectric constant (see, for example, Patent Document 2).

[0004] As described above, metal oxide particles are added to materials to which photolithography is applied in order to achieve various required properties, but there is room for further improvement in dispersibility and transparency for increasing the efficiency of active energy ray irradiation, and in developability and adhesion for forming fine patterns. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-157265 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-155933 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention aims to provide a curable resin composition and a cured film thereof that can be used for fine pattern processing by photolithography even when metal oxide particles are added in accordance with various required properties, can produce a transparent cured film, and can exhibit excellent glass adhesion and film retention. [Means for solving the problem]

[0007] As a result of extensive investigations, the present inventors have found a curable resin composition and a cured film suitable for optical materials. That is, the objects of the present invention are achieved by the following (1) to (15). (1) A curable resin composition comprising metal oxide particles having a number average primary particle size of less than 30 nm, an alkali-soluble polymer, and a polymerizable monomer. (2) The curable resin composition according to (1), wherein the metal forming the metal oxide particles is at least one selected from the group consisting of Ti, Al, Zr, Zn, Sn, Ce, and Si. (3) The curable resin composition according to (1) or (2), wherein the metal oxide particles essentially contain ZrO2 particles. (4) The curable resin composition according to any one of (1) to (3), wherein the metal oxide particles account for 5 to 90% by mass relative to 100% by mass of the total solid content of the curable resin composition. (5) The curable resin composition according to any one of (1) to (4), wherein the metal oxide particles are surface-modified. (6) The curable resin composition according to (5), wherein the metal oxide particles are surface-modified with at least one organic compound selected from the group consisting of an organic acid, a silane coupling agent, a surfactant, and a titanium coupling agent. (7) The curable resin composition according to (6), wherein the modifying amount of the organic compound is 1 to 40 parts by mass per 100 parts by mass of the metal oxide particles. (8) The curable resin composition according to any one of (1) to (7), wherein the alkali-soluble polymer is a polymer having a ring structure in the main chain. (9) The curable resin composition according to any one of (1) to (8), wherein the alkali-soluble polymer is a polymer having a structural unit derived from (meth)acrylic acid. (10) The curable resin composition according to any one of (1) to (9), wherein the alkali-soluble polymer is a polymer having a double bond equivalent of 200 to 10,000 (g / mol). (11) The curable resin composition according to any one of (1) to (10), which is used for forming a high refractive index transparent film. (12) The curable resin composition according to any one of (1) to (11), further comprising an anionic surfactant. (13) A cured film obtained by curing the curable resin composition according to any one of (1) to (12) above. (14) A member for optical materials having the cured film described in (13) above. (15) An optical material having the member for optical materials described in (14) above. [Effects of the Invention]

[0008] By using the curable resin composition of the present invention, it is possible to form fine patterns by photolithography due to its outstanding dispersibility, and to obtain a cured film with high adhesion to glass substrates, etc. Since the cured film can have a high refractive index, high hardness, and high dielectric constant, components and devices having such a cured film will be extremely useful in the optical and electrical / electronic fields. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 10 is a pattern diagram showing the state of the substrate after alkaline development in Example 3. [Figure 2] FIG. 10 is a pattern diagram showing the state of the substrate after alkali development in Example 4. DETAILED DESCRIPTION OF THE INVENTION

[0010] The present invention will be described in detail below. In addition, 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 addition, in this specification, "(meth)acrylic acid" means "acrylic acid and / or methacrylic acid", and "(meth)acrylate" means "acrylate and / or methacrylate". In this specification, the numerical range "Min to Max" means a range equal to or greater than the minimum value Min and equal to or less than the maximum value Max. Furthermore, when preferred numerical values are given in stages for the upper and lower limit values, a numerical range obtained by appropriately combining the separately given upper and lower limit values is also a preferred numerical range. As described above, the curable resin composition of the present invention contains metal oxide particles having an average particle size of more than 1 nm and less than 30 nm, an alkali-soluble polymer, and a polymerizable monomer. By including these components, the curable resin composition is suitable for use in optical materials, and can provide, for example, a cured film with excellent transparency, substrate adhesion, and electrical properties. One or more of these components may be used. Furthermore, if necessary, the composition may further contain one or more other components. In the present invention, the term "optical material" refers to a material used in photolithography for the construction of devices in the optical and electrical / electronic fields. For example, it refers to a material used as a component of color filters, black matrices, photospacers, black column spacers, optical lenses, inks, printing plates, printed wiring boards, semiconductor elements, photoresists, insulating films, etc., used in liquid crystal, organic electroluminescence (EL), quantum dot, and micro LED displays, solid-state imaging devices, and touch panel displays. In particular, since the cured film can have a high refractive index, high hardness, high transparency, and high dielectric constant, it is preferable for the curable resin composition to be used for surface coatings of optical lenses, insulating films for touch sensors, insulating films for TFTs, protective films for touch panels, and quantum dots. Furthermore, when ZrO2 is included as metal oxide particles, the curable resin composition is preferably for use in high refractive index materials (preferably high refractive index optical materials), and more preferably for use in forming high refractive index transparent films. The high refractive index transparent film means a transparent film having a refractive index of 1.5 or more for light of 589 nm and a haze value of 1.1% or less.

[0011] Each component contained in the curable resin composition of the present invention will be described below. In this specification, the term "total solid content" means the total amount of components excluding the solvent that forms the cured film, such as metal oxide particles, alkali-soluble polymer, polymerizable monomer, and surface modifier. [Metal oxide particles with a number average primary particle size of less than 30 nm] Examples of metal oxide particles include optically transparent, high-refractive-index oxide particles containing atoms such as Be, Mg, Ca, Sr, Ba, Sc, Y, La, Ce, Gd, Tb, Dy, Yb, Lu, Ti, Zr, Hf, Nb, Mo, W, Zn, B, Al, Si, Ge, Sn, Pb, Sb, Bi, and Te. Among these, preferred metals for forming the metal oxide particles are Ti, Al, Zr, In, Zn, Sn, La, Y, Ce, Mg, Ba, Ca, and Si. From the viewpoint of providing a cured film with a high refractive index, at least one selected from the group consisting of Ti, Al, Zr, Zn, Sn, and Ce is more preferred. From the viewpoint of providing a cured film with a high dielectric constant, Zr is particularly preferred. From the viewpoint of providing a cured film with high hardness, Si is particularly preferred. Therefore, from the viewpoint of achieving the advantages of both, it is most preferable that the metal oxide particles are zirconium dioxide particles (ZrO2 particles) and / or silicon dioxide particles (SiO2 particles). The metal oxide may be an oxide of a single metal, a solid solution of two or more oxides, or a composite oxide. Examples of single metal oxides include aluminum oxide (Al2O3), titanium oxide (TiO2), zirconium oxide (ZrO2), indium oxide (In2O3), zinc oxide (ZnO), tin oxide (SnO2), lanthanum oxide (La2O3), yttrium oxide (YO3), cerium oxide (CeO2), magnesium oxide (MgO), and silicon oxide (SiO2). Examples of solid solutions of two or more oxides include ITO and ATO. Examples of composite oxides include barium titanate (BaTiO3), perovskite (CaTiO3), and spinel (MgAl2O4). The crystallite diameter of the metal oxide particles calculated by X-ray diffraction analysis is, for example, 20 nm or less. By doing so, the transparency of the curable resin composition containing the metal oxide particles can be improved. The crystallite diameter is more preferably 15 nm or less, and even more preferably 10 nm or less. The lower limit of the crystallite diameter is usually about 1 nm. The particle size of the metal oxide particles can be evaluated by the number average primary particle size obtained by processing images obtained by various electron microscope observations, and the number average primary particle size is less than 30 nm, preferably 25 nm or less. This can improve the transparency of a curable resin composition containing the metal oxide particles. The number average primary particle size is more preferably 20 nm or less, and even more preferably 15 nm or less. The lower limit of the number average primary particle size is preferably a value exceeding 1 nm. More preferably, it is 3 nm or more, and particularly preferably 5 nm or more. It is thought that the adhesiveness, which is one of the effects of the present invention, is exhibited due to the anchoring effect caused by reducing the number average primary particle diameter. Although it is speculation, it is thought that the metal oxide particles having the above particle diameter contained in the curable resin composition all or partly penetrate into the minute irregularities on the substrate surface and harden, thereby increasing the adhesion strength.

[0012] The number average primary particle size can be determined by magnifying and observing the metal oxide particles with a transmission electron microscope (TEM), a field emission transmission electron microscope (FE-TEM), a field emission scanning electron microscope (FE-SEM), or the like, randomly selecting 100 particles, measuring their lengths in the major axis direction, and calculating the arithmetic average. In the present invention, the method described in the column for "Evaluation method (5) Number average primary particle size of metal oxide particles" in the Examples was used. Examples of the shape of the metal oxide particles include spherical, granular, oval sphere, cube, rectangular parallelepiped, pyramidal, needle, columnar, rod, cylinder, scale, plate, thin flake, etc. In consideration of dispersibility in a solvent, the above-mentioned shapes are preferably spherical, granular, columnar, etc. The refractive index of the metal oxide particles is not particularly limited, but from the viewpoint of obtaining a high refractive index, it is preferably 1.70 to 2.70, and more preferably 1.90 to 2.70. The specific surface area of the metal oxide particles is 10 to 400 m 2 / g, and 20 to 200m 2 / g, and more preferably 30 to 150m 2 / g is most preferred. The metal oxide particles are preferably contained in an amount of 1 to 90 mass %, more preferably 5 to 90 mass %, even more preferably 20 to 90 mass %, and most preferably 30 to 80 mass %, relative to 100 mass % of the total solid content of the curable resin composition. When the metal oxide particles are contained within the above range, it is possible to produce a cured film having a high refractive index and excellent adhesion. The metal oxide particles may be either particles surface-modified with a surface modifier (also referred to as coated metal oxide particles) or surface-unmodified particles, and commercially available products may also be used. When the particles are surface-modified, the mass of the metal oxide particles includes the mass of the surface modifier. In the examples (Tables 1 to 3) described below, the mass of the metal oxide particles includes the mass of the surface modifier. The metal oxide particles are preferably surface-modified to enhance their dispersibility in the resin composition. This is to prevent aggregation and allow for fine dispersion so as not to impair the transparency of the cured film. In the present invention, the organic compound that modifies the surface of the metal oxide particles may either be chemically bonded and / or coordinated, or may be attached to the metal oxide particles by hydrogen bonding or salt formation. In the present invention, the term "surface modification" encompasses both a state in which an organic group is chemically bonded and / or coordinated to the metal oxide, and a state in which the organic group is physically attached. The metal oxide particles may be commercially available or may be produced by a known production method. A preferred production method is a hydrothermal reaction between a metal component and an organic compound such as a carboxylic acid compound in the presence of water. For example, it is preferable to use the metal oxide particles and the production methods thereof described in Japanese Patent No. 6227013 and Japanese Patent No. 6251478. The metal component is not particularly limited as long as it is contained in a compound that generates a metal oxide by hydrothermal reaction. Examples of compounds containing a metal component include various metal oxide precursors, such as hydroxides, chlorides, oxychlorides, sulfates, acetates, organic acid salts, and alkoxides of various metals, and also salts of various metals and carboxylic acids. For example, examples of zirconium include zirconium hydroxide, zirconium chloride, zirconyl oxychloride, zirconyl oxyacetate, zirconyl oxynitrate, zirconium sulfate, zirconium octanoate, zirconium 2-ethylhexanoate, zirconium oxide oleate, zirconium acetate, zirconium oxide stearate, zirconium oxide laurate, and zirconium tetrabutoxide. Examples of titanium include titanium hydroxide, titanium chloride, titanium oxychloride, titanium oxyacetate, titanium oxynitrate, titanium sulfate, titanium octanoate, titanium oxide oleate, titanium acetate, titanium oxide stearate, titanium oxide laurate, and titanium alkoxides such as titanium tetrabutoxide (e.g., titanium tetra-n-butoxide).

[0013] In addition, in the case of SiO2 (silica) in which the metal forming the metal oxide is Si, the silica fine particles described in Japanese Patent No. 6166055, paragraphs 0014 to 0019 are preferred.

[0014] Specifically, the silica particles are not particularly limited as long as they are metal oxide particles containing silicon atoms, but may be composite metal oxide particles containing other metal atoms in addition to silicon atoms. The number average primary particle diameter of the silica particles is preferably, for example, 1 nm or more and less than 30 nm. It is more preferably 1 nm or more and 20 nm or less, and particularly preferably 1 nm or more and 15 nm or less. The silica particles may be used in the form of a dried powder or a dispersion (e.g., colloidal silica) dispersed in an organic solvent. However, from the viewpoint of the dispersion stability and production efficiency of the curable resin composition of the present invention, it is preferable to use a dispersion in which the silica particles are previously dispersed in an organic solvent. That is, the silica particles are preferably mixed with other components as an organic solvent dispersion and then contained in the curable resin composition.

[0015] Examples of organic solvents (dispersion media) used to form the dispersion include ketone-based solvents, ester-based solvents, ether-based solvents, alcohol-based solvents, amide-based solvents, xylene, toluene, etc., and one or more of these can be used. Among these, ketone-based solvents, ester-based solvents, and / or ether-based solvents are preferred. Ketone-based solvents and / or ester-based solvents are more preferred, as this further enhances the effects of the present invention, namely, maintaining dispersibility without changes in appearance over time, such as discoloration, coloration, or cracking, even after exposure to high temperatures, and obtaining a cured film with sufficient surface hardness and adhesion. When using a dispersion of silica particles dispersed in an organic solvent, the amount of organic solvent (dispersion media) used is preferably an amount sufficient to sufficiently disperse the silica particles. For example, the total amount of the organic solvent as the dispersion media is preferably 50 parts by mass or more per 100 parts by mass of silica particles. More preferably, it is 70 parts by mass or more, and even more preferably 100 parts by mass or more. Furthermore, considering efficiency, it is preferable that the amount be 600 parts by mass or less. It is more preferably 550 parts by mass or less, and even more preferably 500 parts by mass or less.

[0016] The organic solvent dispersion can be obtained by thoroughly dispersing silica particles in the organic solvent described above, but commercially available products can also be used. Examples of commercially available products include organosilica sols using methyl ethyl ketone as a dispersion medium, such as MEK-ST-40, MEK-ST-L, MEK-ST-ZL, MEK-ST-UP, MEK-AC-2140Z, MEK-AC-4130Y, MEK-EC-2130Y, and MEK-AC-5140Y; organosilica sols using methyl isobutyl ketone as a dispersion medium, such as MIBK-ST, MIBK-ST-L, and MIBK-SD-L; organosilica sols using ethyl acetate as a dispersion medium, such as EAC-ST; organosilica sols using methanol as a dispersion medium, such as methanol silica sol and MA-ST-M; IPA-ST; Examples of organosilica sols include organosilica sols using isopropanol as a dispersion medium, such as IPA-ST-L; organosilica sols using ethylene glycol as a dispersion medium, such as EG-ST; organosilica sols using alkylene glycol monoalkyl ether as a dispersion medium, such as NPC-ST-30, PGM-ST, and PGM-AC-2140Y; organosilica sols using dimethylacetamide as a dispersion medium, such as DMAC-ST; organosilica sols using toluene as a dispersion medium, such as TOL-ST; and organosilica sols using propylene glycol monomethyl acetate as a dispersion medium, such as PMA-ST (all manufactured by Nissan Chemical Industries, Ltd.). The metal oxide particles described above are preferably surface-modified to make them lipophilic, since this can reduce aggregation and allow for fine dispersion. The surface modification is not particularly limited as long as it is a method that can make the particle surface lipophilic, but typically, a compound having an organic group that can form a bond with a metal oxide and a reactive functional group that can make the particle surface lipophilic, such as a silane coupling agent, a titanate-based coupling agent, or an aluminate-based coupling agent, is used. Examples of the reactive functional group include a (meth)acryloyloxy group, an epoxy group, an amino group, a vinyl group, a thiol group, an acid anhydride group, and a phenol group. Therefore, for example, examples of the silane coupling agent include (meth)acryloyloxy-based silane coupling agents such as 3-(meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropylmethyldiethoxysilane, and 3-(meth)acryloyloxypropyltriethoxysilane; diethoxy(glycidyloxypropyl)methylsilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane; Epoxy-based silane coupling agents such as dimethoxysilane and 3-glycidoxypropyltriethoxysilane; and amino-based silane coupling agents such as N-2(aminoethyl)3-aminopropylmethyldimethoxysilane, N-2(aminoethyl)3-aminopropyltrimethoxysilane, N-2(aminoethyl)3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, and N-phenyl-3-aminopropyltrimethoxysilane can be used.

[0017] In such coupling agents, the alkoxy groups, which are hydrolyzable groups, generate hydroxyl groups upon hydrolysis, and these hydroxyl groups form bonds with the surfaces of metal oxide particles. Therefore, the surfaces of particles treated with such surface modifiers have reactive functional groups derived from the coupling agent used for surface modification. In other words, metal oxide particles surface-modified with a coupling agent are metal oxide particles having at least one reactive functional group derived from the coupling agent, selected from (meth)acryloyloxy groups, epoxy groups, amino groups, vinyl groups, thiol groups, acid anhydride groups, and phenol groups. The amount of (silane) coupling agent relative to the metal oxide particles in the (silane) coupling agent treatment is preferably within the range of 0.1 to 100 parts by mass per 100 parts by mass of the metal oxide particles. By setting the amount within this range, the dispersibility of the particles in the composition and the optical performance after curing are improved. The modification amount is more preferably within the range of 1 to 70 parts by mass, and most preferably within the range of 1 to 40 parts by mass. The method of surface modification using a coupling agent such as a silane coupling agent is not particularly limited, but can usually be carried out by adding and mixing metal oxide particles to a dispersion of the silane coupling agent, and heating, etc. as necessary, to cause a reaction. The metal oxide particles may be added in the form of powder particles, or may be added as a slurry or dispersion in which the metal oxide particles are dispersed in an appropriate dispersion medium. Examples of the dispersion medium that can be used here include alcohols such as water, methanol, ethanol, propanol, 2-propanol (IPA), butanol, diacetone alcohol, furfuryl alcohol, and tetrahydrofurfuryl alcohol; methyl acetate, ethyl acetate, isopropyl acetate, propyl acetate, isobutyl acetate, butyl acetate, isopentyl acetate, pentyl acetate, 3-methoxybutyl acetate, 2-ethylbutyl acetate, and cyclohexyl acetate. Examples of suitable solvents include esters such as ethylene glycol monoacetate, glycols such as ethylene glycol and hexylene glycol, hydrophilic solvents including ethers such as diethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol isopropyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether, esters such as propyl acetate, isobutyl acetate, butyl acetate, isopentyl acetate, pentyl acetate, 3-methoxybutyl acetate, 2-ethylbutyl acetate, cyclohexyl acetate, and ethylene glycol monoacetate, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, butyl methyl ketone, cyclohexanone, methylcyclohexanone, dipropyl ketone, methyl pentyl ketone, and diisobutyl ketone, and polar solvents such as toluene. These may be used alone or in combination. The surface-modified metal oxide particles have an affinity for organic solvents because their surfaces are modified with reactive functional groups. Therefore, they are stably dispersed as nanoparticles in the various organic solvents mentioned above. Specifically, they can be treated as a highly transparent solution. The surface-modified metal oxide particles (coated metal oxide particles) may be used in the form of a dispersion in which the metal oxide particles are dispersed in the surface-modifying liquid used for the surface modification, or may be used as a powder after distilling off the solvent under reduced pressure.

[0018] The solid content of the metal oxide particles in the dispersion liquid is not particularly limited, but is preferably 20 to 90% by mass, and more preferably 50 to 80% by mass. The surface-modified metal oxide particles suitable for use in the present invention may be further surface-modified with an organic compound other than the above-mentioned coupling agent. Examples of organic compounds used for surface modification include organic compounds having a substituent capable of coordinating and / or bonding to the surface of metal oxide particles, such as a carboxyl group, a hydroxyl group, an alkoxy group, an amine group, a thiol group, or an amide group, as well as silane coupling agents and surfactants. One or more of these may be used. Organic acids (preferably organic compounds having a carboxyl group), other coupling agents, and surfactants are preferred because they have a strong bond to metal oxide particles, impart hydrophobic properties to the particles, and minimize adverse effects such as discoloration of the cured film. These organic compounds may or may not have reactive functional groups. The modifying amount of the organic compound is preferably in the range of 0 to 50 parts by mass, more preferably 1 to 40 parts by mass, and most preferably 2 to 30 parts by mass, per 100 parts by mass of the metal oxide particles. By adjusting the amount to the above range, the hardness, refractive index, and relative dielectric constant of the cured film are further improved. As the organic compound, a carboxylic acid (a compound having a carboxyl group) having 5 or more carbon atoms is preferred because it improves the dispersibility of the metal oxide particles in the medium. When the carboxylic acid has 5 or more carbon atoms, the surface of the metal oxide particles can be sufficiently hydrophobicized, further improving the dispersibility of the particles in the medium. Examples of the aliphatic carboxylic acids having 5 or more carbon atoms include pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, 2-ethylhexanoic acid, 2-methylheptanoic acid, 4-methyloctanoic acid, salicylic acid, naphthenic acid, decanoic acid, undecylic acid, neodecanoic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, pivalic acid, 2,2-dimethylbutyric acid, 3,3-dimethylbutyric acid, 2,2-dimethylvaleric acid, 2,2-diethylbutyric acid, 3,3-diethylbutyric acid, stearic acid, pristanic acid, 2-acryloyloxyethylhexahydrophthalic acid, 2-methacryloyloxyethylhexahydrophthalic acid, acrylic acid, methacrylic acid, 2-acryloyloxyethylsuccinic acid, and 2-methacryloyloxyethylsuccinic acid. 3-9 (Meth)acryloyloxy C of aliphatic dicarboxylic acids 1-6Half esters with alkyl alcohols; C such as 2-acryloyloxyethyl phthalate and 2-methacryloyloxyethyl phthalate 8-14 (Meth)acryloyloxy C of aromatic dicarboxylic acids 1-6 Examples include half esters of alkyl alcohols, and they may be used alone or in combination of two or more. The surfactant may be an ionic surfactant such as an anionic surfactant, a cationic surfactant, or an amphoteric surfactant, or a nonionic surfactant. Examples of anionic surfactants include fatty acid sodium surfactants such as sodium oleate, sodium stearate, and sodium laurate; fatty acid potassium surfactants; fatty acid surfactants such as sodium fatty acid ester sulfonate; phosphate surfactants such as alkyl phosphoric acid, alkyl phosphate esters, and sodium alkyl phosphate esters; olefin surfactants such as sodium alpha olein sulfonate; alcohol surfactants such as sodium alkyl sulfate; and alkyl benzene surfactants. Examples of cationic surfactants include alkylmethylammonium chloride, alkyldimethylammonium chloride, alkyltrimethylammonium chloride, and alkyldimethylbenzylammonium chloride. Examples of zwitterionic surfactants include carboxylic acid surfactants such as alkylaminocarboxylates, and phosphate ester surfactants such as phosphobetaine. Examples of nonionic surfactants include fatty acid surfactants such as polyoxyethylene lanolin fatty acid esters and polyoxyethylene sorbitan fatty acid esters, polyoxyethylene alkylphenyl ethers, and fatty acid alkanolamides. The method for modifying the surfaces of metal oxide particles with the organic compound can be any known method, such as mixing and stirring various organic compounds and metal oxide particles in a solvent or mixing using a ball mill. When a carboxylic acid is used as the organic compound, a suitable production method is to carry out a hydrothermal reaction of a metal component with a carboxylic acid compound in the presence of water, in addition to mixing. In the case of a carboxylic acid compound, it is also possible to exchange the type of carboxylic acid by transesterification. Curing can be further promoted by appropriately selecting the surface modifier for the metal oxide particles depending on the type and content of the alkali-soluble polymer and polymerizable monomer contained in the curable resin composition of the present invention. Such surface-modified metal oxide particles can bond together by radical polymerization, addition reaction, or addition-condensation reaction depending on the type of reactive functional group on the surface, thereby increasing the strength and hardness of the cured film. Among the above-mentioned metal oxide particles, the metal oxide particles described in the inorganic particle dispersion of JP 2018-119086 A are preferred. Specifically, the metal oxide particles preferably contain at least one of an organic acid, a silane coupling agent, a surfactant, and a titanium coupling agent as a surface modifier, and preferably contain at least an organic acid. The inclusion of an organic acid can improve dispersibility. Furthermore, surface modification can further facilitate high-concentration dispersion and improve thixotropy.

[0019] As the organic acid, a compound having a carboxyl group (hereinafter, sometimes referred to as a "carboxylic acid compound") is preferable, and the above-mentioned carboxylic acid compound may form a salt with a cation (e.g., a metal cation such as an alkali metal cation or an alkaline earth metal cation; a molecular cation such as an ammonium ion). The metal oxide particles preferably contain two or more carboxylic acid compounds as organic acids. Coated metal oxide particles coated with two or more carboxylic acid compounds have excellent dispersibility in various media and can be used in a variety of applications. They are particularly useful for forming precise microstructures, such as resists, and can improve dispersion unevenness and development residues. As the surface modifier for the metal oxide particles, the above-mentioned surfactants and / or titanium coupling agents may be used. Examples of the titanium coupling agent include isopropyl triisostearoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tri(dodecyl)benzenesulfonyl titanate, neopentyl(diallyl)oxy-tri(dioctyl)phosphate titanate, and neopentyl(diallyl)oxy-trineododecanoyl titanate. It is particularly preferred that the metal oxide particles are surface-modified with a silane coupling agent. Surface modification with a silane coupling agent not only improves the initial transmittance of the composition and its cured film, but also facilitates maintaining the transmittance for a long period of time. One or more types of the silane coupling agent may be used, and the hydrolyzable group -Si-OR 1 (However, R 1 is a methyl group or an ethyl group) is preferred. Examples of the silane coupling agent include a silane coupling agent having a functional group and an alkoxysilane.

[0020] The silane coupling agent having a functional group is a silane coupling agent having the following formula (1):

[0021] [ka] (wherein X is a functional group, R 1 is the same as above, m represents an integer of 0 to 4, and n represents an integer of 1 to 3. Examples of X include a vinyl group, an amino group, a (meth)acryloxy group, a mercapto group, a glycidoxy group, etc. Specific examples of the silane coupling agent include silane coupling agents in which the functional group X is a vinyl group, such as vinyltrimethoxysilane and vinyltriethoxysilane; silane coupling agents in which the functional group X is an amino group, such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane and N-2-(aminoethyl)-3-aminopropylmethyltrimethoxysilane; 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldimethoxysilane; Examples include silane coupling agents in which the functional group X is a (meth)acryloxy group, such as methoxysilane and 3-methacryloxypropylmethyldiethoxysilane; silane coupling agents in which the functional group X is a mercapto group, such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane; and silane coupling agents in which the functional group X is a glycidoxy group, such as 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropylmethyldiethoxysilane. Examples of alkoxysilanes include alkyl group-containing alkoxysilanes in which the alkyl group is directly bonded to the silicon atom of the alkoxysilane, such as methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, propyltrimethoxysilane, butyltriethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octyltriethoxysilane, and decyltrimethoxysilane; and aryl group-containing alkoxysilanes in which an aromatic ring is directly bonded to the silicon atom of the alkoxysilane, such as phenyltrimethoxysilane, diphenyldimethoxysilane, and p-styryltrimethoxysilane.

[0022] As the silane coupling agent, a silane coupling agent in which the functional group X is a (meth)acryloxy group and an alkyl group-containing alkoxysilane are preferred, and 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, hexyltrimethoxysilane, octyltriethoxysilane, and decyltrimethoxysilane are more preferred.

[0023] The amount of the silane coupling agent (coating amount) is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, even more preferably 2 parts by mass or more, and even more preferably 4 parts by mass or more, relative to 100 parts by mass of the metal oxide particles, and is preferably 40 parts by mass or less, more preferably 20 parts by mass or less, even more preferably 15 parts by mass or less, and even more preferably 12 parts by mass or less. By setting the content of the silane coupling agent within the above range, the refractive index of the metal oxide particles and the composition thereof can be maintained.

[0024] When an organic acid and a silane coupling agent are contained as the surface modifier, the mass ratio of the silane coupling agent to the organic acid (silane coupling agent / organic acid) is preferably 0.01 to 2.0, more preferably 0.1 to 1.5, and even more preferably 0.2 to 0.95. When the amount of the silane coupling agent is within the above range, the dispersibility of the metal oxide particles is good.

[0025] The concentration of the metal oxide particles can be appropriately set depending on the application. When the curable resin composition of the present invention is uncured or contains a polymer (resin), the concentration is typically 90% by mass or less relative to 100% by mass of all components of the composition (the total of all components used, such as (coated) metal oxide particles, solvent, polymerizable monomer, and alkali-soluble polymer). There is no particular lower limit, but considering the cost of the solvent, it is, for example, 1% by mass or more. It is more preferably 5% by mass or more and 85% by mass or less, and even more preferably 10% by mass or more and 80% by mass or less. To further improve the dispersibility of the curable resin composition of the present invention, it is preferable to add a dispersant or a dispersion aid. These are not particularly limited as long as they disperse the metal oxide particles, but representative examples include surfactants. By adjusting the type and content of the surfactant in advance to produce a metal oxide particle dispersion, and then mixing it with other components to produce the curable resin composition of the present invention, the transparency of the curable resin composition is increased and production efficiency is also improved.

[0026] Examples of surfactants include anionic surfactants, cationic surfactants, zwitterionic surfactants, and nonionic surfactants. Examples of anionic surfactants include sodium fatty acids such as sodium oleate, sodium stearate, and sodium laurate; fatty acid surfactants such as potassium fatty acids and sodium fatty acid ester sulfonates; phosphate surfactants such as sodium alkyl phosphate esters; olefin surfactants such as sodium alpha olein sulfonate; alcohol surfactants such as sodium alkyl sulfate; and alkylbenzene surfactants. Examples of cationic surfactants include alkylmethylammonium chloride, alkyldimethylammonium chloride, alkyltrimethylammonium chloride, and alkyldimethylbenzylammonium chloride. Examples of zwitterionic surfactants include carboxylic acid surfactants such as alkylaminocarboxylates; and phosphate ester surfactants such as phosphobetaine. Examples of nonionic surfactants include fatty acid surfactants such as polyoxyethylene lanolin fatty acid esters and polyoxyethylene sorbitan fatty acid esters; polyoxyethylene alkylphenyl ethers; fatty acid alkanolamides; and phosphate surfactants such as organic phosphate esters, alkyl phosphate esters, phosphate polyesters, and polyoxyalkylene alkyl ether phosphate esters.

[0027] Furthermore, the dispersibility of the metal oxide particles is significantly improved by surface modification and the addition of the surfactant, and the composition has good transparency even at high concentrations. A composition in which metal oxide particles are dispersed at high concentrations is advantageous, for example, in improving the refractive index, making it possible to adjust the refractive index according to various applications. When the metal oxide particles are used as a high-concentration metal oxide particle composition, the amount of metal oxide particles in the composition is preferably 25% by mass or more, more preferably 30% by mass or more, and even more preferably 60% by mass or more. Although there is no particular upper limit, the amount of metal oxide particles in the composition is preferably 90% by mass or less. Furthermore, when preparing a composition containing the metal oxide particles of the present invention, dispersibility can be further improved by adding additives such as linear carboxylic acids such as hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, tetradecanoic acid, and stearic acid; branched carboxylic acids such as 2-ethylhexanoic acid, 2-methylheptanoic acid, 4-methyloctanoic acid, and neodecanoic acid; cyclic carboxylic acids such as naphthenic acid and cyclohexanedicarboxylic acid, and 2-acryloyloxyethyl succinic acid, 2-acryloyloxyethyl hexahydrophthalic acid, 2-acryloyloxyethyl phthalic acid, 2-methacryloyloxyethyl succinic acid, 2-methacryloyloxyethyl hexahydrophthalic acid, and 2-methacryloyloxyethyl phthalic acid, and this is a preferred embodiment.

[0028] The surfactant or additive may typically be added in an amount of 0.01% by mass to 10% by mass, more preferably 0.1% by mass to 5% by mass, and even more preferably 0.3% by mass to 3% by mass, relative to 100% by mass of all components of the curable resin composition. Blending these makes it possible to improve the transparency and dispersibility of the composition. Furthermore, it is also possible to achieve a low viscosity of the composition. Furthermore, a curable resin composition in which the surfactant is contained in an amount ranging from 0.3% by mass to 3% by mass, relative to 100% by mass of the total amount of the curable resin composition, is the most preferred embodiment. Furthermore, when preparing a metal oxide particle dispersion liquid in advance, the surfactant or additive may be added in an amount of 0.1% by mass or more and 20% by mass or less, more preferably 0.5% by mass or more and 10% by mass or less, and even more preferably 1% by mass or more and 5% by mass or less, relative to 100% by mass of all components of the metal oxide particle dispersion liquid. In addition, for metal oxide particles that do not contain a surface modifier, or for metal oxide particles that contain a surface modifier but exclude it, the content is preferably 5% by mass or more relative to 100% by mass of the total solid content of the curable resin composition. This further improves the physical properties of the cured film. It is more preferably 10% by mass or more, and even more preferably 15% by mass or more. Furthermore, from the viewpoints of developability, dispersion stability, etc., it is preferably 80% by mass or less. It is more preferably 70% by mass or less, even more preferably 60% by mass or less, particularly preferably 50% by mass or less, and most preferably 45% by mass or less. Furthermore, when ZrO2 particles and SiO2 particles are used in combination as metal oxide particles (when individual metal oxide particles are mixed rather than a composite oxide), the mass ratio (ZrO2 particles / SiO2 particles) is preferably 99 / 1 to 10 / 90, more preferably 90 / 10 to 30 / 70, even more preferably 80 / 20 to 40 / 60, and particularly preferably 70 / 30 to 50 / 50. By keeping the ratio within the above range, a cured film with a high refractive index, high hardness, and high adhesion to the substrate can be obtained.

[0029] [Alkali-soluble polymer] The alkali-soluble polymer is a polymer that exhibits alkali solubility. Preferably, it has a weight-average molecular weight of 5,000 or more. Use of a polymer with a weight-average molecular weight of 5,000 or more significantly improves developability. It is preferably 7,000 or more, more preferably 10,000 or more, and even more preferably 12,000 or more. From the viewpoint of viscosity and the like, it is preferably 250,000 or less. It is more preferably 100,000 or less, even more preferably 50,000 or less, particularly preferably 30,000 or less, and most preferably 20,000 or less. When the alkali-soluble polymer has a high molecular weight, the higher the acid value, the easier it is to develop. The weight average molecular weight can be determined, for example, by GPC (gel permeation chromatography) using polystyrene as a standard substance, tetrahydrofuran as an eluent, HLC-8320GPC (manufactured by Tosoh Corporation) and a column TSKgel SuperHZM-M (manufactured by Tosoh Corporation).

[0030] The alkali-soluble polymer is also preferably a polymer having an acid group in the molecule (also referred to as an "acid group-containing polymer"). Examples of the acid group include functional groups that undergo a neutralization reaction with alkaline water, such as a carboxyl group, a phenolic hydroxyl group, a carboxylic anhydride group, a phosphoric acid group, and a sulfonic acid group. The polymer may have only one of these groups or two or more of these groups. Among these, a carboxyl group or a carboxylic anhydride group is preferred, and a carboxyl group is more preferred.

[0031] When the alkali-soluble polymer is a polymer having an acid group, the acid value (AV) of the alkali-soluble polymer is not particularly limited, but is preferably, for example, 20 mgKOH / g or more and less than 300 mgKOH / g. This allows for more sufficient alkali solubility to be exhibited, making it possible to obtain a cured film with better developability. The lower limit of the acid value is more preferably 30 mgKOH / g or more, even more preferably 40 mgKOH / g or more, and most preferably 100 mgKOH / g or more. It is more preferably 250 mgKOH / g or less, even more preferably 200 mgKOH / g or less. The acid value of the polymer can be determined, for example, by measuring the acid value of the polymer solution using a 0.1N KOH aqueous solution as a titrant with an automatic titrator (manufactured by Hiranuma Sangyo Co., Ltd., product name "COM-1700A") and calculating the acid value per solid content from the acid value of the solution and the solid content of the solution. The solid content of the polymer solution can also be determined as follows. Approximately 0.3 g of the polymer solution was weighed into an aluminum cup, dissolved in approximately 1 g of acetone, and then allowed to dry naturally at room temperature. The solution was then dried at 140°C for 3 hours using a hot air dryer (manufactured by Espec Corporation, product name "PHH-101"), cooled in a desiccator, and the mass was measured. The solids concentration of the polymer solution was calculated from the mass loss. Evaluations were performed using the methods described in the evaluation methods (2) and (3) of the Examples.

[0032] The alkali-soluble polymer is preferably, for example, a polymer (also referred to as a base polymer) obtained by polymerizing a monomer component containing a monomer having an acid group and a polymerizable double bond, or a polymer (also referred to as a side-chain double-bond-containing polymer) obtained by reacting the base polymer with a compound having a functional group capable of bonding to an acid group and a polymerizable double bond, as described below. More preferably, it is a polymer having a polymerizable double bond in the side chain (side-chain double-bond-containing polymer). Each of the monomers used may be used alone or in combination of two or more.

[0033] The alkali-soluble polymer is particularly preferably a polymer having a ring structure in the main chain. When a polymer having a ring structure in the main chain is used as the alkali-soluble polymer, a cured film can be obtained that is more excellent in heat resistance, surface hardness, and adhesion, and can more stably exhibit various physical properties. Thus, an embodiment in which the alkali-soluble polymer is a polymer having a ring structure in the main chain is also one of the preferred embodiments of the present invention. Therefore, it is preferable that the monomer components forming the base polymer contain, in addition to a monomer having an acid group and a polymerizable double bond, one or more monomers capable of introducing a ring structure into the main chain skeleton of the polymer. Examples of the monomer capable of introducing a ring structure into the main chain skeleton of the polymer include a monomer having a double bond-containing ring structure in the molecule and a monomer that undergoes cyclopolymerization to form a polymer having a ring structure in the main chain.

[0034] Examples of the monomer having an acid group and a polymerizable double bond include unsaturated monocarboxylic acids such as (meth)acrylic acid, crotonic acid, cinnamic acid, and vinylbenzoic acid; unsaturated polycarboxylic acids such as maleic acid, fumaric acid, itaconic acid, citraconic acid, and mesaconic acid; unsaturated monocarboxylic acids in which the unsaturated group and the carboxyl group are chain-extended, such as mono(2-acryloyloxyethyl) succinate and mono(2-methacryloyloxyethyl) succinate; unsaturated acid anhydrides such as maleic anhydride and itaconic anhydride; and phosphoric acid group-containing unsaturated compounds such as Light Ester P-1M (manufactured by Kyoeisha Chemical Co., Ltd.). Among these, from the viewpoints of versatility, availability, and the like, it is preferable to use carboxylic acid-based monomers (unsaturated monocarboxylic acids, unsaturated polycarboxylic acids, and unsaturated acid anhydrides). More preferably, in terms of reactivity, alkali solubility, etc., it is preferable to use unsaturated monocarboxylic acids, and even more preferably (meth)acrylic acid (i.e., acrylic acid and / or methacrylic acid), and among these, methacrylic acid is particularly preferred. That is, an alkali-soluble polymer having a structural unit derived from methacrylic acid is particularly preferred. The structural unit derived from methacrylic acid refers to a site in a polymer into which a structure derived from methacrylic acid has been introduced by a polymerization reaction or addition reaction of methacrylic acid.

[0035] The content of the monomer having an acid group and a polymerizable double bond is preferably, for example, 5% by mass or more relative to 100% by mass of the base polymer component. This provides sufficient alkali solubility, making the curable resin composition even more useful for applications requiring developability, for example. Furthermore, in order to further maintain the excellent appearance and adhesion of the cured film, the content is preferably 85% by mass or less. It is more preferably 10 to 80% by mass, and even more preferably 15 to 75% by mass.

[0036] The monomer component may contain, in addition to the above-mentioned monomer having an acid group and a polymerizable double bond, other radically polymerizable monomers (hereinafter also referred to as "other monomers"). As the other monomer, for example, as described above, one or more monomers capable of introducing a ring structure into the main chain skeleton of the polymer, such as a monomer having a double bond-containing ring structure in the molecule or a monomer that undergoes cyclopolymerization to form a polymer having a ring structure in the main chain, are suitable. As such a monomer, it is preferred to use at least one selected from the group consisting of N-substituted maleimide monomers, dialkyl-2,2'-(oxydimethylene)diacrylate monomers, and α-(unsaturated alkoxyalkyl)acrylates. A preferred embodiment of the present invention is one in which the alkali-soluble polymer is a polymer having N-substituted maleimide monomer units, dialkyl-2,2'-(oxydimethylene)diacrylate monomer units, and / or α-(unsaturated alkoxyalkyl)acrylate monomer units. As the other monomer, one or more of other (meth)acrylic acid ester-based monomers and aromatic vinyl-based monomers can also be suitably used. In particular, polymers containing N-substituted maleimide monomer units and / or dialkyl-2,2'-(oxydimethylene)diacrylate monomer units are excellent in heat resistance and dispersibility (dispersibility of metal oxide particles, pigment particles, etc.), and can provide cured films with improved hardness, etc. The polymer containing the above-mentioned monomer units means, for example, a polymer containing structural units derived from the monomers by a polymerization reaction or crosslinking reaction of the monomers.

[0037] In the above-mentioned monomer component, examples of the N-substituted maleimide monomer include N-cyclohexylmaleimide, N-phenylmaleimide, N-methylmaleimide, N-ethylmaleimide, N-isopropylmaleimide, Nt-butylmaleimide, N-dodecylmaleimide, N-benzylmaleimide, and N-naphthylmaleimide, and one or more of these can be used. Among them, N-cyclohexylmaleimide, N-phenylmaleimide, and N-benzylmaleimide are preferred, and N-benzylmaleimide is particularly preferred, in terms of low coloration and excellent dispersibility. Examples of the N-benzylmaleimide include benzylmaleimide; alkyl-substituted benzylmaleimides such as p-methylbenzylmaleimide and p-butylbenzylmaleimide; phenolic hydroxyl group-substituted benzylmaleimides such as p-hydroxybenzylmaleimide; and halogen-substituted benzylmaleimides such as o-chlorobenzylmaleimide, o-dichlorobenzylmaleimide and p-dichlorobenzylmaleimide.

[0038] As the dialkyl-2,2'-(oxydimethylene)diacrylate monomer, it is preferable to use, for example, dimethyl-2,2'-[oxybis(methylene)]bis-2-propenoate, etc., from the viewpoints of low coloration, dispersibility, ease of industrial availability, etc.

[0039] Examples of the α-(unsaturated alkoxyalkyl)acrylate include α-allyloxymethylacrylic acid, methyl α-allyloxymethylacrylate, ethyl α-allyloxymethylacrylate, n-propyl α-allyloxymethylacrylate, i-propyl α-allyloxymethylacrylate, n-butyl α-allyloxymethylacrylate, s-butyl α-allyloxymethylacrylate, t-butyl α-allyloxymethylacrylate, n-amyl α-allyloxymethylacrylate, s-amyl α-allyloxymethylacrylate, t-amyl α-allyloxymethylacrylate, neopentyl α-allyloxymethylacrylate, n-hexyl α-allyloxymethylacrylate, s-hexyl α-allyloxymethylacrylate, n-heptyl α-allyloxymethylacrylate, n-octyl α-allyloxymethylacrylate, s-octyl α-allyloxymethylacrylate, Preferred are α-(allyloxymethyl)acrylates containing a chain saturated hydrocarbon group, such as t-octyl α-allyloxymethylacrylate, 2-ethylhexyl α-allyloxymethylacrylate, capryl α-allyloxymethylacrylate, nonyl α-allyloxymethylacrylate, decyl α-allyloxymethylacrylate, undecyl α-allyloxymethylacrylate, lauryl α-allyloxymethylacrylate, tridecyl α-allyloxymethylacrylate, myristyl α-allyloxymethylacrylate, pentadecyl α-allyloxymethylacrylate, cetyl α-allyloxymethylacrylate, heptadecyl α-allyloxymethylacrylate, stearyl α-allyloxymethylacrylate, nonadecyl α-allyloxymethylacrylate, eicosyl α-allyloxymethylacrylate, ceryl α-allyloxymethylacrylate, and melissyl α-allyloxymethylacrylate. Among these, methyl α-allyloxymethylacrylate (also referred to as "α-(allyloxymethyl)methyl acrylate") is particularly suitable. The above-mentioned α-(unsaturated alkoxyalkyl)acrylate can be produced, for example, by the production method disclosed in WO 2010 / 114077.

[0040] The content of the N-substituted maleimide monomer, dialkyl-2,2'-(oxydimethylene)diacrylate monomer, and / or α-(unsaturated alkoxyalkyl)acrylate (the total content when two or more types are used) is, for example, preferably 1% by mass or more and 40% by mass or less, based on 100% by mass of the base polymer component. Within this range, a cured film with improved heat resistance, dispersibility, surface hardness, and the like can be obtained. Increasing the content of the main chain ring structure derived from these monomer components tends to improve adhesion. Furthermore, increasing the amount of N-substituted maleimide monomer added results in a cured film with superior hardness, and the use of dialkyl-2,2'-(oxydimethylene)diacrylate monomer results in a cured film with superior heat discoloration resistance. If the content of the N-substituted maleimide monomer is too high, the development speed may not be optimal. The content of the structural units derived from the N-substituted maleimide monomer, the structural units derived from the dialkyl-2,2'-(oxydimethylene)diacrylate monomer, and / or the structural units derived from the α-(unsaturated alkoxyalkyl)acrylate relative to 100% by mass of all monomer units is more preferably 2 to 40% by mass, and even more preferably 3 to 35% by mass.

[0041] The other (meth)acrylic acid ester monomers mentioned above mean (meth)acrylic acid ester monomers other than dialkyl-2,2'-(oxydimethylene)diacrylate monomers and α-(unsaturated alkoxyalkyl)acrylates, and include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, n-amyl (meth)acrylate, s-amyl (meth)acrylate, (meth)acrylic acid ester monomers, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, n-amyl (meth)acrylate, s-amyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, ethyl ... p) t-Amyl acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, tridecyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclohexylmethyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, tricyclo (meth)acrylate Decanyl, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, (meth)acrylic acid β-Ethylglycidyl, (3,4-epoxycyclohexyl)methyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, methyl α-hydroxymethylacrylate, ethyl α-hydroxymethylacrylate, etc., as well as 1,4-dioxaspiro[4,5]dec-2-ylmethacrylic acid, (meth)acryloylmorpholine, tetrahydrofurfuryl acrylate, 4-(meth)acryloyloxymethyl-2-methyl-2-ethyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl-2-methyl-2-isobutyl-1,Examples of such compounds include 3-dioxolane, 4-(meth)acryloyloxymethyl-2-methyl-2-cyclohexyl-1,3-dioxolane, 4-(meth)acryloyloxymethyl-2,2-dimethyl-1,3-dioxolane, and alkoxylated phenylphenol (meth)acrylate. Commercially available products of these compounds include MMDOL30, MEDOL30, MIBDOL30, CHDOL30, MEDOL10, MIBDOL10, MIBDOL10, CHDOL10, Viscoat 150, and Viscoat 160 (all manufactured by Osaka Organic Chemical Industry Ltd.), ACMO (manufactured by Kohjinsha), and A-LEN-10 (manufactured by Shin-Nakamura Chemical Co., Ltd.). Among these, methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, and alkoxylated phenylphenol (meth)acrylate are preferred due to their excellent heat resistance. It is more preferable to use methyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, and / or alkoxylated phenylphenol (meth)acrylate, because they have excellent heat resistance, adhesion, and developability. Furthermore, from the viewpoint of solubility, alicyclic hydrocarbon group-containing monomers (units), particularly alicyclic (meth)acrylate-derived structural units, are preferred. Alicyclic hydrocarbon group-containing monomers are described in detail below. The alicyclic hydrocarbon group-containing monomer includes a monomer having an alicyclic hydrocarbon group and a polymerizable double bond. The alicyclic hydrocarbon group preferably includes an alicyclic hydrocarbon group having 3 to 12 carbon atoms, more preferably 7 to 10 carbon atoms. Specific examples include monocyclic hydrocarbon groups such as cyclopropyl, cyclopentyl, cyclohexyl, cyclooctyl, cyclododecyl, cycloheptyl, cyclobutenyl, cyclopentenyl, and cyclohexenyl; and polycyclic hydrocarbon groups such as dicyclopentanyl, dicyclopentenyl, tricyclodecanyl, adamantyl, and isobornyl. Among these, the alicyclic hydrocarbon group is preferably a polycyclic hydrocarbon group, more preferably dicyclopentanyl, dicyclopentenyl, or isobornyl, and particularly preferably dicyclopentanyl, in order to exhibit even better solubility and heat discoloration resistance. Examples of the polymerizable double bond include a (meth)acryloyl group, a vinyl group, an allyl group, and a methallyl group. The monomer having the polymerizable double bond is preferably a (meth)acrylate monomer. That is, the alicyclic hydrocarbon group-containing monomer is preferably an alicyclic hydrocarbon group-containing (meth)acrylate monomer.

[0042] Examples of the aromatic vinyl monomer include styrene, vinyltoluene, α-methylstyrene, methoxystyrene, etc. Among them, styrene and vinyltoluene are preferred in terms of solubility, heat discoloration resistance and heat decomposition resistance of the polymer. The constituent units derived from aromatic vinyl monomers will be described in detail below. The aromatic vinyl monomer is a monomer having an aromatic group and a vinyl group. The aromatic group increases steric hindrance near the main chain and can suppress association of acid groups, thereby contributing to suppression of cloudiness during synthesis. Furthermore, the aromatic group contributes to dispersion stability, and when a curable resin composition is prepared, it can suppress the generation of residues during development. Examples of the aromatic group include groups containing a benzene ring or a naphthalene ring, with groups containing a benzene ring being preferred. The aromatic group may have a substituent. Examples of the substituent include an alkyl group having 1 to 5 carbon atoms and an alkoxy group having 1 to 5 carbon atoms. Examples of the aromatic vinyl monomer include styrene, vinyltoluene, α-methylstyrene, xylene, methoxystyrene, and ethoxystyrene. Among these, styrene and vinyltoluene are preferred because of their improved thermal decomposition resistance. Furthermore, vinyltoluene is more preferred because of its high dissolution rate in organic solvents and alkalis and the methyl group contributes to the above-mentioned improved steric hindrance and hydrophobicity. Considering compatibility with other monomers, the content is preferably 10 to 90% by mass relative to 100% by mass of the total amount of all monomers during polymerization. Considering polymerizability, the content is more preferably 15% by mass or more, even more preferably 25% by mass or more, and more preferably 85% by mass or less, even more preferably 80% by mass or less, relative to 100% by mass of the total amount of all monomers. Examples of the vinyltoluene include o-vinyltoluene, p-vinyltoluene, and m-vinyltoluene. Among these, m-vinyltoluene, p-vinyltoluene, and a mixture of m-vinyltoluene and p-vinyltoluene, which are easily available industrially, are preferred, and a mixture of m-vinyltoluene and p-vinyltoluene, which is easily available industrially, is particularly preferred. In the case of an alkali-soluble polymer modified to have side chain double bonds, the proportion of vinyltoluene units in all monomer units is not particularly limited, but is preferably 5 to 85 mass %, more preferably 10 to 80 mass %, and even more preferably 20 to 70 mass % of all monomer units. By keeping it within the above range, the solubility in alkali and the thermal stability become even better. The content of the other (meth)acrylic acid ester monomer and / or aromatic vinyl monomer (the total content when two or more types are used) is preferably, for example, 1 to 80% by mass relative to 100% by mass of the base polymer component. Within this range, a cured film with superior heat discoloration resistance, dispersibility, alkali solubility, etc. can be obtained. The content is more preferably 5 to 75% by mass, and even more preferably 10 to 70% by mass.

[0043] The other monomer may also be, for example, one or more of the following compounds, and the content thereof is preferably 20% by mass or less, and preferably 10% by mass or less, based on 100% by mass of the base polymer component: (meth)acrylamides such as N,N-dimethyl(meth)acrylamide and N-methylol(meth)acrylamide; macromonomers having a (meth)acryloyl group at one end of the polymer molecular chain, such as polystyrene, polymethyl(meth)acrylate, polyethylene oxide, polypropylene oxide, polysiloxane, polycaprolactone, and polycaprolactam; conjugated dienes such as 1,3-butadiene, isoprene, and chloroprene; vinyl esters such as vinyl acetate, vinyl propionate, vinyl butyrate, and vinyl benzoate; methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, butyl vinyl ether, 2-ethyl vinyl ether, ... Vinyl ethers such as hexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, cyclohexyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, methoxypolyethylene glycol vinyl ether, 2-hydroxyethyl vinyl ether, and 4-hydroxybutyl vinyl ether; N-vinyl compounds such as N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylimidazole, N-vinylmorpholine, and N-vinylacetamide; unsaturated isocyanates such as isocyanatoethyl (meth)acrylate and allyl isocyanate.

[0044] As a method for polymerizing the above-mentioned monomer components, commonly used techniques such as bulk polymerization, solution polymerization, emulsion polymerization, etc. can be used, and may be appropriately selected depending on the purpose and application. Among them, solution polymerization is preferred because it is industrially advantageous and allows easy structural adjustment such as molecular weight. Furthermore, as a polymerization mechanism for the above-mentioned monomer components, polymerization methods based on mechanisms such as radical polymerization, anionic polymerization, cationic polymerization, and coordination polymerization can be used, but polymerization methods based on a radical polymerization mechanism are preferred because they are industrially advantageous.

[0045] The polymerization initiation method for the above polymerization reaction can be achieved by supplying the energy required to initiate polymerization to the monomer components from an active energy source such as heat, electromagnetic waves (infrared rays, ultraviolet rays, X-rays, etc.), or electron beams, and the use of a polymerization initiator in combination is preferable because it can significantly reduce the energy required to initiate polymerization and also facilitates reaction control. The molecular weight of the polymer obtained by polymerizing the above monomer components can be controlled by adjusting the amount and type of polymerization initiator, the polymerization temperature, the type and amount of chain transfer agent, etc.

[0046] When the above-mentioned monomer components are polymerized by a solution polymerization method, the solvent used for the polymerization is not particularly limited as long as it is inert to the polymerization reaction, and may be appropriately selected depending on the polymerization conditions such as the polymerization mechanism, the type and amount of the monomers used, the polymerization temperature, and the polymerization concentration. However, when a solvent is used as a diluent or the like when a curable resin composition is subsequently produced, it is efficient and preferable to use a solvent containing the solvent for the solution polymerization of the monomer components.

[0047] Suitable examples of the solvent include the following compounds, and one or more of these can be used. Monoalcohols such as methanol, ethanol, isopropanol, n-butanol, and s-butanol; glycols such as ethylene glycol and propylene glycol; cyclic ethers such as tetrahydrofuran and dioxane; glycol monoethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, and 3-methoxybutanol; glycol ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol ethyl methyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol dimethyl ether, and propylene glycol diethyl ether; ethylene glycol monomethyl ether acetate glycol monoether esters such as ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, and 3-methoxybutyl acetate; alkyl esters such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, methyl propionate, ethyl propionate, butyl propionate, methyl lactate, ethyl lactate, butyl lactate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl acetoacetate, and ethyl acetoacetate;Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, etc.; aliphatic hydrocarbons such as hexane, cyclohexane, octane, etc.; amides such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.;

[0048] Among these solvents, it is more preferable to use propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol ethyl methyl ether, and ethyl lactate in view of the solubility of the resulting polymer, the surface smoothness when a coating film is formed, the small impact on the human body and the environment, and the ease of industrial availability.

[0049] The amount of the solvent used is preferably 50 to 1000 parts by mass, and more preferably 100 to 500 parts by mass, per 100 parts by mass of the base polymer component.

[0050] When the monomer components are polymerized by a radical polymerization mechanism, it is industrially advantageous and preferable to use a polymerization initiator that generates radicals by heat. Such a polymerization initiator is not particularly limited as long as it generates radicals by supplying thermal energy, and may be appropriately selected depending on the polymerization conditions, such as the polymerization temperature, solvent, and type of monomer to be polymerized. In addition, a reducing agent such as a transition metal salt or an amine may be used in combination with the polymerization initiator.

[0051] Examples of the polymerization initiator include peroxides and azo compounds that are typically used as polymerization initiators, such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, di-t-butyl peroxide, lauroyl peroxide, benzoyl peroxide, t-butylperoxyisopropyl carbonate, t-butylperoxy-2-ethylhexanoate, azobisisobutyronitrile, 1,1′-azobis(cyclohexanecarbonitrile), 2,2′-azobis(2,4-dimethylvaleronitrile), dimethyl 2,2′-azobis(2-methylpropionate), hydrogen peroxide, and persulfates, and these may be used alone or in combination of two or more thereof. The amount of the polymerization initiator used is not particularly limited and may be appropriately determined depending on the type and amount of monomer used, polymerization conditions such as polymerization temperature and polymerization concentration, and the molecular weight of the target polymer. For example, to obtain a polymer with a weight-average molecular weight of several thousand to several tens of thousands, the amount is preferably 0.1 to 20 parts by mass, and more preferably 0.5 to 15 parts by mass, per 100 parts by mass of the base polymer component. In order to reduce the concentration of oligomers (e.g., molecular weights of 500 or less) and obtain a polymer with a narrow molecular weight distribution, the amount is preferably 0.1 to 10 parts by mass, and more preferably 0.5 to 3 parts by mass, per 100 parts by mass of all monomer components (total amount of all monomers: 100 parts by mass).

[0052] In the polymerization, a commonly used chain transfer agent may be used as needed. Preferably, a polymerization initiator and a chain transfer agent are used in combination. The use of a chain transfer agent during polymerization tends to suppress an increase in molecular weight distribution and gelation.

[0053] Examples of the chain transfer agent include mercaptocarboxylic acids such as mercaptoacetic acid and 3-mercaptopropionic acid; mercaptocarboxylic acid esters such as methyl mercaptoacetate, methyl 3-mercaptopropionate, 2-ethylhexyl 3-mercaptopropionate, n-octyl 3-mercaptopropionate, methoxybutyl 3-mercaptopropionate, stearyl 3-mercaptopropionate, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate), and dipentaerythritol hexakis(3-mercaptopropionate); ethyl mercaptan, t-butyl mercaptan, and n-dodecyl Examples of suitable mercaptans include alkyl mercaptans such as mercaptan and 1,2-dimercaptoethane; mercaptoalcohols such as 2-mercaptoethanol and 4-mercapto-1-butanol; aromatic mercaptans such as benzenethiol, m-toluenethiol, p-toluenethiol, and 2-naphthalenethiol; mercaptoisocyanurates such as tris[(3-mercaptopropionyloxy)-ethyl]isocyanurate; disulfides such as 2-hydroxyethyl disulfide and tetraethyl thiuram disulfide; dithiocarbamates such as benzyl diethyl dithiocarbamate; monomer dimers such as α-methylstyrene dimer; and alkyl halides such as carbon tetrabromide. These may be used alone or in combination of two or more.

[0054] Among these, compounds having a mercapto group such as mercaptocarboxylic acids, mercaptocarboxylic acid esters, alkyl mercaptans, mercaptoalcohols, aromatic mercaptans, and mercaptoisocyanurates are preferably used in terms of availability, crosslinking prevention ability, small degree of decrease in polymerization rate, etc. Alkyl mercaptans, mercaptocarboxylic acids, and mercaptocarboxylic acid esters are more preferred, and n-dodecyl mercaptan and mercaptopropionic acid are even more preferred.

[0055] The amount of the chain transfer agent used is not particularly limited and may be appropriately determined depending on the type and amount of the monomer used, polymerization conditions such as polymerization temperature and polymerization concentration, the molecular weight of the target polymer, etc., but to obtain a polymer having a weight-average molecular weight of several thousand to several tens of thousands, the amount is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 15 parts by mass, per 100 parts by mass of the base polymer component.

[0056] Regarding the polymerization conditions, the polymerization temperature may be appropriately set depending on the type and amount of the monomer used, the type and amount of the polymerization initiator, etc., and is, for example, preferably 50 to 150° C., more preferably 70 to 120° C. Similarly, the polymerization time may also be appropriately set, and is, for example, preferably 1 to 5 hours, more preferably 2 to 4 hours. The alkali-soluble polymer also preferably has a double bond in the side chain, specifically, a polymer (also referred to as a polymer having a polymerizable double bond in the side chain) obtained by reacting a polymer (base polymer) obtained by polymerizing the monomer components with a compound having a functional group capable of bonding to an acid group and a polymerizable double bond.

[0057] In the compound having a functional group capable of bonding to an acid group and a polymerizable double bond, examples of the polymerizable double bond include a (meth)acryloyl group, a vinyl group, an allyl group, and a methallyl group, and the compound preferably has one or more of these. Among these, a (meth)acryloyl group is preferred in terms of reactivity. Furthermore, examples of the functional group capable of bonding to an acid group include a hydroxy group, an epoxy group, an oxetanyl group, an isocyanate group, and an oxazoline group, and the compound preferably has one or more of these. Among these, an epoxy group (including a glycidyl group) is preferred in terms of the speed of the modification treatment reaction, heat resistance, and dispersibility. When a double bond is introduced into a side chain, it is particularly preferred to add a compound containing at least one selected from an epoxy group, an oxazoline group, an isocyanate group, and a hydroxy group and a polymerizable unsaturated double bond, preferably in an amount of 5 to 120% by mass, more preferably 5 to 80% by mass, and particularly preferably 5 to 60% by mass, based on the polymer (base polymer). By adjusting the amount within the above range, the exposure sensitivity, developability, and storage stability become good.

[0058] The compound having a functional group capable of bonding to an acid group and a polymerizable double bond is preferably glycidyl (meth)acrylate, β-methylglycidyl (meth)acrylate, β-ethylglycidyl (meth)acrylate, vinylbenzyl glycidyl ether, allyl glycidyl ether, (3,4-epoxycyclohexyl)methyl (meth)acrylate, vinylcyclohexene oxide, etc., and one or more of these can be used. Among these, it is preferable to use a compound (monomer) having an epoxy group and a (meth)acryloyl group.

[0059] Examples of methods for obtaining the side-chain double bond-containing polymer include a method in which, when the base polymer component is reacted with a compound having a functional group capable of bonding to an acid group and a polymerizable double bond, the amount of acid groups (preferably carboxyl groups) in the base polymer component is in excess of the amount of the compound having a functional group capable of bonding to an acid group and a polymerizable double bond; and a method in which, after reacting the base polymer component with a compound having a functional group capable of bonding to an acid group and a polymerizable double bond, the compound is further reacted with a compound having a polybasic acid anhydride group.

[0060] The step of reacting the base polymer component (preferably a polymer having a carboxyl group) with the compound having a functional group capable of bonding to an acid group and a polymerizable double bond is preferably carried out at a temperature in the range of 50 to 160°C to ensure a good reaction rate and prevent gelation. The temperature is more preferably 70 to 140°C, and even more preferably 90 to 130°C. To improve the reaction rate, a basic catalyst or acidic catalyst commonly used for esterification or transesterification can be used as a catalyst. Among these, the use of a basic catalyst is preferred because it reduces side reactions.

[0061] Examples of the basic catalyst include tertiary amines such as dimethylbenzylamine, triethylamine, tri-n-octylamine, and tetramethylethylenediamine; quaternary ammonium salts such as tetramethylammonium chloride, tetramethylammonium bromide, tetrabutylammonium bromide, and n-dodecyltrimethylammonium chloride; urea compounds such as tetramethylurea; alkylguanidines such as tetramethylguanidine; amide compounds such as dimethylformamide and dimethylacetamide; tertiary phosphines such as triphenylphosphine and tributylphosphine; and quaternary phosphonium salts such as tetraphenylphosphonium bromide and benzyltriphenylphosphonium bromide. One or more of these may be used. Among these, dimethylbenzylamine, triethylamine, tetramethylurea, and triphenylphosphine are preferred in terms of reactivity, ease of handling, and halogen-free properties.

[0062] The amount of the catalyst used is preferably 0.01 to 5.0 parts by mass, more preferably 0.1 to 3.0 parts by mass, per 100 parts by mass of the total amount of the base polymer component and the compound having a functional group capable of bonding to an acid group and a polymerizable double bond group.

[0063] The step of reacting the base polymer component with the compound having a polymerizable double bond and a functional group capable of bonding to an acid group is preferably carried out in the presence of a molecular oxygen-containing gas, typically air or oxygen gas diluted with an inert gas such as nitrogen, in order to prevent gelation.

[0064] The polymerization inhibitor may be a polymerization inhibitor commonly used for radically polymerizable monomers, such as hydroquinone, methylhydroquinone, trimethylhydroquinone, t-butylhydroquinone, methoquinone, 6-t-butyl-2,4-xylenol, 2,6-di-t-butylphenol, 2,6-di-t-butyl-4-methoxyphenol, or 2,2'-methylenebis(4-methyl-6-t-butylphenol), or a copper salt of an organic acid or a phenothiazine. One or more of these may be used. Among these, phenolic inhibitors are preferred in terms of low coloration and polymerization-inhibiting ability, and 2,2'-methylenebis(4-methyl-6-t-butylphenol), methoquinone, 6-t-butyl-2,4-xylenol, or 2,6-di-t-butylphenol are more preferred in terms of availability and economy.

[0065] The amount of the polymerization inhibitor used is preferably 0.001 to 1.0 part by mass, more preferably 0.01 to 0.5 part by mass, relative to 100 parts by mass of the total amount of the base polymer component and the compound having a functional group capable of bonding to an acid group and a polymerizable double bond, from the viewpoints of ensuring a sufficient polymerization-inhibiting effect and curing properties when the curable resin composition is prepared.

[0066] Examples of the compound having a polybasic acid anhydride group include succinic anhydride, dodecenylsuccinic acid, pentadecenylsuccinic acid, octadecenylsuccinic acid, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, maleic anhydride, itaconic anhydride, phthalic anhydride, glutaric anhydride, phthalic anhydride, trimellitic anhydride, and pyromellitic anhydride, and one or more of these can be used.

[0067] The alkali-soluble polymer having a polymerizable double bond in its side chain (side-chain double-bond-containing polymer) preferably contained in the composition of the present invention has a double bond equivalent of 200 to 10,000 (g / mol). By setting the double bond equivalent within this range, it is expected that sufficient storage stability of the polymer and excellent plate-making properties, such as developability and adhesion, of the curable resin composition of the present invention can be achieved at an even higher level. The double bond equivalent is more preferably 250 or more, even more preferably 300 or more, particularly preferably 350 or more, and even more preferably 400 or more. It is also more preferably 5,000 or less, even more preferably 4,000 or less, particularly preferably 2,500 or less, even more preferably 1,500 or less, even more preferably 1,000 or less, and most preferably 800 or less. The double bond equivalent is the mass (g) of the solid content of the polymer solution per 1 mol of double bonds in the polymer. The mass of the solid content of the polymer solution is the sum of the mass of the monomer components constituting the polymer and the mass of the chain transfer agent (the mass of the base polymer component, the mass of the compound having a functional group capable of bonding to an acid group and a polymerizable double bond group, and the mass of the chain transfer agent). The double bond equivalent can be calculated by dividing the mass (g) of the polymer solid content of the polymer solution by the amount of double bonds (mol) in the polymer. The amount of double bonds in the polymer can be determined by confirming the structures of the acid group-containing monomer and the compound having a polymerizable double bond (the compound having a functional group capable of bonding to an acid group and a polymerizable double bond) used in the polymerization and determining their amounts. It can also be measured using various analyses such as titration, elemental analysis, NMR, and IR, or differential scanning calorimetry. For example, it can be calculated by measuring the number of ethylenic double bonds contained per gram of polymer in accordance with the iodine value test method described in JIS K 0070:1992. Furthermore, the glass transition temperature (Tg) of the side chain double bond-containing polymer is preferably 80°C or lower. This improves adhesion. It is more preferably 70°C or lower, even more preferably 60°C or lower, particularly preferably 50°C or lower, and most preferably 40°C or lower. There are no particular restrictions on the lower limit, but from the viewpoint of heat resistance, it is preferably -10°C or higher, and more preferably 0°C or higher. The glass transition temperature (Tg) can be measured, for example, by the following method. The copolymer solution is applied to a 5cm square glass substrate, spin-coated onto the glass substrate, and dried at room temperature under reduced pressure for 4 hours to form a thin film with a mass of 30mg or less, thereby removing volatile components and obtaining a solid content. The obtained solid content is measured using a DSC (differential scanning calorimeter, measuring device: Netsch DSC3500) in a nitrogen stream at a heating rate of 10°C / min in accordance with JIS-K7121.

[0068] In the curable resin composition, the content of the alkali-soluble polymer is preferably 5% by mass or more and suitably 70% by mass or less, relative to 100% by mass of the total solid content of the curable resin composition. By being in this range, the effects of the present invention can be more significantly exhibited. It is more preferably 10 to 65% by mass, even more preferably 10 to 50% by mass, particularly preferably 10 to 40% by mass, even more preferably 10 to 35% by mass, and most preferably 15 to 35% by mass. [Polymerizable monomer] The polymerizable monomer is a low molecular weight compound having a polymerizable unsaturated bond (also referred to as a polymerizable unsaturated group) that can be polymerized by irradiation with active energy rays such as free radicals, electromagnetic waves (e.g., infrared rays, ultraviolet rays, X-rays, etc.), and electron beams. Examples include monofunctional compounds having one polymerizable unsaturated group in the molecule and polyfunctional compounds having two or more polymerizable unsaturated groups. The molecular weight is not particularly limited, but from the viewpoint of ease of handling, it is preferably 3000 or less, and more preferably 2000 or less.

[0069] Examples of the monofunctional polymerizable monomer include, among the compounds exemplified as other monomers preferably contained in the monomer component of the alkali-soluble polymer, N-substituted maleimides and (meth)acrylic acid esters; (meth)acrylamides; unsaturated monocarboxylic acids; unsaturated polycarboxylic acids; unsaturated monocarboxylic acids in which the unsaturated group and the carboxyl group are chain-extended; unsaturated acid anhydrides; aromatic vinyls; conjugated dienes; vinyl esters; vinyl ethers; N-vinyl compounds; and unsaturated isocyanates.

[0070] Examples of the polyfunctional polymerizable monomer include the following compounds. Bifunctional (meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, hexanediol di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, bisphenol A alkylene oxide di(meth)acrylate, and bisphenol F alkylene oxide di(meth)acrylate Acrylate compounds; trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, tripentaerythritol octa(meth)acrylate, ethylenediamine Ethylene oxide-added trimethylolpropane tri(meth)acrylate, Ethylene oxide-added ditrimethylolpropane tetra(meth)acrylate, Ethylene oxide-added pentaerythritol tetra(meth)acrylate, Ethylene oxide-added dipentaerythritol hexa(meth)acrylate, Propylene oxide-added trimethylolpropane tri(meth)acrylate, Propylene oxide-added ditrimethylolpropane tetra(meth)acrylate, Propylene oxide-added pentaerythritol hexa(meth)acrylate tri- or higher functional polyfunctional (meth)acrylate compounds such as erythritol tetra(meth)acrylate, propylene oxide-added dipentaerythritol hexa(meth)acrylate, ε-caprolactone-added trimethylolpropane tri(meth)acrylate, ε-caprolactone-added ditrimethylolpropane tetra(meth)acrylate, ε-caprolactone-added pentaerythritol tetra(meth)acrylate, and ε-caprolactone-added dipentaerythritol hexa(meth)acrylate; Ethylene glycol divinyl ether, diethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butylene glycol divinyl ether, hexanediol divinyl ether, bisphenol A alkylene oxide divinyl ether, bisphenol F alkylene oxide divinyl ether, trimethylolpropane trivinyl ether, ditrimethylolpropane tetravinyl ether, glycerin trivinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether, ethylene oxide-added trimethylolpropane trivinyl ether, ethylene oxide-added ditrimethylolpropane tetravinyl ether, ethylene oxide-added pentaerythritol tetravinyl ether polyfunctional vinyl ethers such as dipentaerythritol vinyl ether and ethylene oxide-added dipentaerythritol hexavinyl ether; vinyl ether group-containing (meth)acrylic acid esters such as 2-vinyloxyethyl (meth)acrylate, 3-vinyloxypropyl (meth)acrylate, 1-methyl-2-vinyloxyethyl (meth)acrylate, 2-vinyloxypropyl (meth)acrylate, 4-vinyloxybutyl (meth)acrylate, 4-vinyloxycyclohexyl (meth)acrylate, 5-vinyloxypentyl (meth)acrylate, 6-vinyloxyhexyl (meth)acrylate, 4-vinyloxymethylcyclohexylmethyl (meth)acrylate, p-vinyloxymethylphenylmethyl (meth)acrylate, 2-(vinyloxyethoxy)ethyl (meth)acrylate, and 2-(vinyloxyethoxyethoxyethoxy)ethyl (meth)acrylate; Ethylene glycol diallyl ether, diethylene glycol diallyl ether, polyethylene glycol diallyl ether, propylene glycol diallyl ether, butylene glycol diallyl ether, hexanediol diallyl ether, bisphenol A alkylene oxide diallyl ether, bisphenol F alkylene oxide diallyl ether, trimethylolpropane triallyl ether, ditrimethylolpropane tetraallyl ether, glycerin triallyl ether, pentaerythritol tetraallyl ether, dipentaerythritol pentaallyl ether, dipentaerythritol hexaallyl ether, ethylene oxide-added trimethylolpropane triallyl ether, ethylene oxide-added ditrimethylolpropane tetraallyl ether, ethylene oxide-added pentaerythritol tetraallyl ether, ethylene oxide-added dipentaerythritol hexaallyl ether polyfunctional allyl ethers such as allyl ether; allyl group-containing (meth)acrylic acid esters such as allyl (meth)acrylate; polyfunctional (meth)acryloyl group-containing isocyanurates such as tri(acryloyloxyethyl)isocyanurate, tri(methacryloyloxyethyl)isocyanurate, alkylene oxide-added tri(acryloyloxyethyl)isocyanurate, and alkylene oxide-added tri(methacryloyloxyethyl)isocyanurate; polyfunctional allyl group-containing isocyanurates such as triallyl isocyanurate; polyfunctional urethane (meth)acrylates obtained by reacting polyfunctional isocyanates such as tolylene diisocyanate, isophorone diisocyanate, and xylylene diisocyanate with hydroxyl group-containing (meth)acrylic acid esters such as 2-hydroxyethyl (meth)acrylate and 2-hydroxypropyl (meth)acrylate; polyfunctional aromatic vinyls such as divinylbenzene; and the like.

[0071] A particularly preferred polymerizable monomer, a polyfunctional (meth)acrylate compound having two or more functional groups, will be described in detail below. A difunctional or higher polyfunctional (meth)acrylate compound (hereinafter simply referred to as a "polyfunctional (meth)acrylate compound") is a compound having two or more (meth)acryloyl groups in one molecule. By including such a compound, the curable resin composition has excellent photosensitivity and curability, and it is possible to obtain a cured film with extremely high hardness and transparency. The number of functions of the polyfunctional (meth)acrylate compound is preferably 3 or more, more preferably 4 or more, and even more preferably 5 or more. Furthermore, from the viewpoint of further suppressing cure shrinkage, the number of functions is preferably 10 or less, more preferably 8 or less, and even more preferably 6 or less. The (meth)acryloyl group refers to a methacryloyl group and / or an acryloyl group, with an acryloyl group being preferred from the viewpoint of superior reactivity. That is, it is particularly preferable that the polyfunctional (meth)acrylate compound is a polyfunctional acrylate compound having two or more acryloyl groups.

[0072] The content of the polymerizable monomer may be appropriately set depending on the type of polymerizable monomer and alkali-soluble polymer used, as well as the purpose and application, but from the viewpoint of superior developability and plate-making properties, it is preferably 2% by mass or more and suitably 85% by mass or less, relative to 100% by mass of the total solids content of the curable resin composition. The lower limit is more preferably 5% by mass or more, even more preferably 10% by mass or more, and particularly preferably 15% by mass or more, and the upper limit is more preferably 75% by mass or less, even more preferably 60% by mass or less, particularly preferably 50% by mass or less, and most preferably 40% by mass or less. The content of the polymerizable monomer is preferably 50 to 500 parts by mass relative to 100 parts by mass of the alkali-soluble polymer. A polymerizable monomer content within this range not only provides a cured film with higher surface hardness, but also, coupled with the preferred weight-average molecular weight of the alkali-soluble polymer being 5,000 or greater, improves developability. The content is more preferably 80 parts by mass or greater, even more preferably 100 parts by mass or greater, and particularly preferably 120 parts by mass or greater. From the perspective of further improving developability, the content is more preferably 400 parts by mass or less. The content is even more preferably 300 parts by mass or less, particularly preferably 200 parts by mass or less, and most preferably 150 parts by mass or less.

[0073] [Photopolymerization initiator] The curable resin composition preferably further contains a photopolymerization initiator. The photopolymerization initiator is preferably a radically polymerizable photopolymerization initiator. The radically polymerizable photopolymerization initiator generates polymerization-initiating radicals upon irradiation with active energy rays such as electromagnetic waves or electron beams, and one or more commonly used initiators can be used. Furthermore, one or more photosensitizers, photoradical polymerization accelerators, etc. may be used in combination, as needed. Sensitivity and curability are further improved by using a photosensitizer and / or a photoradical polymerization accelerator together with the photopolymerization initiator.

[0074] Specific examples of the photopolymerization initiator include the following compounds. alkylphenone compounds such as 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)benzyl]phenyl}-2-methylpropan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone; Benzophenone compounds such as benzophenone, 4,4'-bis(dimethylamino)benzophenone, and 2-carboxybenzophenone; benzoin compounds such as benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; Thioxanthone compounds such as thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, and 2,4-diethylthioxanthone; halomethylated triazine compounds such as 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-ethoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, and 2-(4-ethoxycarboxynylnaphthyl)-4,6-bis(trichloromethyl)-s-triazine; halomethylated oxadiazole compounds such as 2-trichloromethyl-5-(2'-benzofuryl)-1,3,4-oxadiazole, 2-trichloromethyl-5-[β-(2'-benzofuryl)vinyl]-1,3,4-oxadiazole, 4-oxadiazole, and 2-trichloromethyl-5-furyl-1,3,4-oxadiazole; biimidazole compounds such as 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2,2'-bis(2,4-dichlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, and 2,2'-bis(2,4,6-trichlorophenyl)-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); Titanocene compounds such as bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium; Benzoic acid ester compounds such as p-dimethylaminobenzoic acid and p-diethylaminobenzoic acid; Acridine compounds such as 9-phenylacridine; benzyl ketal compounds such as 2,2-dimethoxy-1,2-diphenylethan-1-one ("IRGACURE 651", manufactured by BASF) and phenylglyoxylic acid methyl ester ("DAROCUR MBF", manufactured by BASF); hydroketone compounds such as 1-hydroxycyclohexylphenyl ketone ("IRGACURE184", manufactured by BASF), 2-hydroxy-2-methyl-1-phenylpropan-1-one ("DAROCUR1173", manufactured by BASF), 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one ("IRGACURE2959", manufactured by BASF), 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]-phenyl}-2-methyl-propan-1-one ("IRGACURE127", manufactured by BASF), and [1-hydroxycyclohexylphenyl ketone + benzophenone] ("IRGACURE500", manufactured by BASF); phosphine oxide compounds such as 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide ("LUCIRIN TPO", manufactured by BASF) and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide ("IRGACURE819", manufactured by BASF); aminoketone compounds such as 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one ("IRGACURE907", manufactured by BASF), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 ("IRGACURE369", manufactured by BASF), and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one ("IRGACURE379", manufactured by BASF); titanocene compounds such as bis(η5-2,4-cyclopentadien-1-yl)-bis(2,6-difluoro-3-(1H-pyrrol-1-yl)-phenyl)titanium ("IRGACURE784", manufactured by BASF); Oxime ester compounds such as 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)] ("IRGACURE OXE01", manufactured by BASF);

[0075] Among the above photopolymerization initiators, it is particularly preferable to use at least an aminoketone-based compound (also referred to as an aminoketone-based polymerization initiator). That is, it is preferable that the curable resin composition further contains an aminoketone-based polymerization initiator. This results in better hardness and developability. It is also preferable to use a hydroketone-based compound (also referred to as a hydroketone-based polymerization initiator) or a benzyl ketal-based compound (also referred to as a benzyl ketal-based polymerization initiator).

[0076] Examples of the photosensitizer or photoradical polymerization accelerator that may be used in combination with the photopolymerization initiator include dye compounds such as xanthene dyes, coumarin dyes, 3-ketocoumarin compounds, and pyrromethene dyes; dialkylaminobenzene compounds such as ethyl 4-dimethylaminobenzoate and 2-ethylhexyl 4-dimethylaminobenzoate; and mercaptan hydrogen donors such as 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, and 2-mercaptobenzimidazole.

[0077] The content of the photopolymerization initiator may be appropriately set depending on the purpose, application, etc., and is not particularly limited, but is preferably 0.5 parts by mass or more per 100 parts by mass of the total solid content of the curable resin composition. This makes it possible to obtain a cured film with excellent adhesion, and peeling is more sufficiently suppressed even after exposure to high temperatures. The content is more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more. Furthermore, taking into consideration the balance between the effects of decomposition products of the photopolymerization initiator and economic efficiency, the content is preferably 35 parts by mass or less. The content is more preferably 30 parts by mass or less, and even more preferably 25 parts by mass or less.

[0078] In the present invention, as described above, it is preferable to use an aminoketone polymerization initiator as the polymerization initiator, and in this case, the aminoketone polymerization initiator preferably accounts for 20% by mass or more, more preferably 30% by mass or more, even more preferably 50% by mass or more, and particularly preferably 55% by mass or more but less than 100% by mass, relative to 100% by mass of the total amount of polymerization initiators (i.e., the total amount of the aminoketone polymerization initiator and other polymerization initiators).

[0079] The content (total amount) of the photosensitizer and photoradical polymerization accelerator may be appropriately set depending on the purpose and application and is not particularly limited, but from the viewpoint of balancing curability, the effects of decomposition products, and economic efficiency, it is preferably 0.001 to 20 mass%, more preferably 0.01 to 15 mass%, and even more preferably 0.05 to 10 mass%, relative to 100 mass% of the total solid content of the curable resin composition of the present invention. [solvent] The curable resin composition also preferably contains a solvent. The solvent is preferably used as a diluent or the like. Specifically, the solvent is preferably used to reduce viscosity and improve handling; to form a coating film by drying; as a dispersion medium for a colorant; and the like, and is a low-viscosity organic solvent or water that can dissolve or disperse each component contained in the curable resin composition.

[0080] The solvent may be any commonly used solvent and may be appropriately selected depending on the purpose and application, and is not particularly limited, but examples thereof include the following compounds, which may be used alone or in combination of two or more: Monoalcohols such as methanol, ethanol, isopropanol, n-butanol, and s-butanol; glycols such as ethylene glycol and propylene glycol; cyclic ethers such as tetrahydrofuran and dioxane; glycol monoethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, and 3-methoxybutanol; glycol ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol ethyl methyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, propylene glycol dimethyl ether, and propylene glycol diethyl ether; ethylene glycol monomethyl ether acetate glycol monoether esters such as ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether acetate, dipropylene glycol monobutyl ether acetate, and 3-methoxybutyl acetate; alkyl esters such as methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, methyl propionate, ethyl propionate, butyl propionate, methyl lactate, ethyl lactate, butyl lactate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 3-ethoxypropionate, ethyl 3-ethoxypropionate, methyl acetoacetate, and ethyl acetoacetate;Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.; aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, etc.; aliphatic hydrocarbons such as hexane, cyclohexane, octane, etc.; amides such as dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc.; water, etc.

[0081] The amount of the solvent used may be appropriately determined depending on the purpose and application and is not particularly limited, but is preferably 10 to 90 mass %, more preferably 20 to 80 mass %, relative to 100 mass % of the total amount of the curable resin composition of the present invention. [Polymerization inhibitor] The curable resin composition may also contain one or more polymerization inhibitors in order to more appropriately control the curing reaction. Examples of polymerization inhibitors that can be used include compounds that are typically used as ultraviolet absorbers, light stabilizers (HALS), antioxidants (including anti-aging agents), etc. Specific examples include the following compounds: hydroxyphenyltriazine (HPT)-based ultraviolet absorbers such as TINUVIN 400, TINUVIN 405 (reaction product of 2-(2,4-dihydroxyphenyl)-4,6-bis-(2,4-dimethylphenyl)-1,3,5-triazine and (2-ethylhexyl)glycidic acid ester), TINUVIN 460 (2,4-bis[2-hydroxy-4-butoxyphenyl]-6-(2,4-dibutoxyphenyl)-1,3-5-triazine), TINUVIN 477 (water-dispersed hydroxyphenyltriazine (HPT)-based ultraviolet absorber), TINUVIN 479 (all manufactured by BASF), and Adeka STAB LA-46 (all manufactured by ADEKA); benzotriazole-based ultraviolet absorbers such as Tinuvin PS (2-(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole), Tinuvin 99-2, Tinuvin 384-2, Tinuvin 900 (2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol), Tinuvin 928 (2-(2H-benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol), Tinuvin 1130 (all manufactured by BASF), Adeka STAB LA-29, Adeka STAB LA-31, Adeka STAB LA-32, and Adeka STAB LA-36 (all manufactured by ADEKA); Tinuvin 111FDL, Tinuvin 123, Tinuvin 144 (bis(1,2,2,6,6-pentamethyl-4-piperidyl)[{3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl}methyl]butylmalonate), Tinuvin 292 (mixture of bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate and methyl 1,2,2,6,6-pentamethyl-4-piperidylsebacate), Light stabilizers (HALS) such as Tinuvin 5100 (all manufactured by BASF), Adeka Stab LA-52, Adeka Stab LA-57, Adeka Stab LA-63P, Adeka Stab LA-68, Adeka Stab LA-72, Adeka Stab LA-77, Adeka Stab LA-81, Adeka Stab LA-82, Adeka Stab LA-87, Adeka Stab LA-402XP, and Adeka Stab LA-502XP (all manufactured by ADEKA); Antage W-300 (4,4'-butylidene-bis(6-tert-butyl-m-cresol)), Antage W-400 (2,2'-methylene-bis(4-methyl-6-tert-butylphenol)), Antage W-500 (2,2'-methylene-bis(4-ethyl-6-tert-butylphenol)), Antage Crystal (4,4'-thio-bis(6-tert-butyl-m-cresol)), Antage BHT (2,6-di-tert-butyl-p-cresol), Antage DAH (2,5-di-tert-amine phenolic antioxidants such as ANTAGE DBH (2,5-di-tert-butylhydroquinone), ANTAGE SP (styrenated phenol), ANTAGE 2LX (phenol derivative), ANTAGE 3LX (phenol derivative), ANTAGE W-200 (all manufactured by Kawaguchi Chemical Industry Co., Ltd.), ADK STAB AO-20, ADK STAB AO-30, ADK STAB AO-40, ADK STAB AO-50, ADK STAB AO-60, ADK STAB AO-80, and ADK STAB AO-330 (all manufactured by ADEKA Corporation); Phosphite antioxidants such as ADK STAB PEP-4C, ADK STAB PEP-8, ADK STAB PEP-8C, ADK STAB PEP-36, ADK STAB HP-10, ADK STAB 2112, ADK STAB 2112RG, ADK STAB 1178, ADK STAB 1500, ADK STAB C, ADK STAB 135A, ADK STAB 3010, and ADK STAB TPP (all manufactured by ADEKA Corporation); Thioether antioxidants such as ADK STAB AO-412S and ADK STAB AO-503 (both manufactured by ADEKA Corporation); Amine antioxidants such as Antage 3C (N-isopropyl-N'-phenyl-p-phenylenediamine), Antage 6C (N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine), Antage STDP-N (phenothiazine derivative), Antage LDA (diphenylamine derivative), Antage OD (diphenylamine derivative), Antage DDA (diphenylamine derivative), Antage RD (polymerized 2,2,4-trimethyl-1,2-dihydroquinoline), Antage AW (6-ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline), Antage F, Antage D, Antage DP, and Antage ODPP (all manufactured by Kawaguchi Chemical Industry Co., Ltd.); and the like.

[0082] Among the above polymerization inhibitors, it is preferable to use at least a phenolic antioxidant. That is, it is also preferable that the curable resin composition further contains a phenolic antioxidant. This makes it possible to obtain a cured film that can stably exhibit even more excellent transparency, hardness, and developability even after exposure to a high-temperature environment.

[0083] The content of the polymerization inhibitor may be appropriately set depending on the purpose, application, etc., and is not particularly limited, but is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.1% by mass or more, relative to 100% by mass of the total solid content of the curable resin composition. Furthermore, it is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less. In the present invention, as described above, it is particularly preferred to use a phenolic antioxidant as the polymerization inhibitor. In this case, the amount of the phenolic antioxidant is preferably 50 parts by mass or more per 100 parts by mass of the total amount of polymerization inhibitors (i.e., the total amount of the phenolic antioxidant and other polymerization inhibitors). More preferably, it is 70 parts by mass or more, and even more preferably, it is 90 parts by mass or more. It is particularly preferred to use 100 parts by mass, i.e., to use substantially only the phenolic antioxidant as the polymerization inhibitor.

[0084] [Other ingredients] The curable resin composition may further contain, depending on the required properties of each application to which it is applied, one or more of the following: coloring materials (also referred to as colorants) such as pigments and dyes; quantum dot particles (quantum dot particles other than the above-mentioned metal oxide particles); dispersants; surfactants; heat resistance improvers; leveling agents; coupling agents (the coupling agents exemplified as the surface modifiers for the above-mentioned metal oxide particles); development aids; fillers, thermosetting resins such as epoxy resins, phenolic resins, and polyvinylphenols; curing agents; release agents; reactive diluents; stabilizers; flame retardant aids; curing aids such as polyfunctional thiol compounds; fluorine-based additives; plasticizers; ultraviolet absorbers; antioxidants; matting agents; antifoaming agents; antistatic agents; slip agents; surface modifiers; thixotropic agents; thixotropic aids; quinone diazide compounds; polyhydric phenol compounds; cationically polymerizable compounds; acid generators; other polymerizable monomers; crosslinking agents. [Method for producing curable resin composition] The curable resin composition can be prepared by mixing and dispersing the above-described components using various conventional mixers or dispersers. Among these, it is preferable to first disperse metal oxide particles in an organic solvent (dispersion medium) to obtain an organic solvent dispersion of metal oxide particles (metal oxide particle dispersion), and then mix the dispersion with an alkali-soluble polymer, a polymerizable monomer, and other components as needed to obtain a curable resin composition. The curable resin composition obtained in this manner further exhibits the effects of the present invention. Thus, a method for producing the curable resin composition, which includes a step of dispersing metal oxide particles in an organic solvent to obtain an organic solvent dispersion of metal oxide particles (also referred to as the "dispersion step") and a step of mixing the dispersion with other components, such as an alkali-soluble polymer (also referred to as the "mixing step"), is also a preferred embodiment of the present invention. It is particularly preferable to surface-modify the metal oxide particles with a surface modifier (also referred to as the "surface modification step"). A method for producing a curable resin composition, which includes a surface modification step before, after, or during the dispersion step, is also a preferred embodiment of the present invention. The surface modifier preferably contains at least one of the above-mentioned organic acid, silane coupling agent, surfactant, and titanium coupling agent. That is, in a method for producing a curable resin composition comprising a step of mixing metal oxide particles having a number average primary particle diameter of less than 30 nm, an alkali-soluble polymer, and a polymerizable monomer, one particularly preferred embodiment of the present invention is to mix the metal oxide particles with a dispersion that has been subjected to a process comprising the surface modification process and the dispersion process. The dispersing step and the mixing step are not particularly limited and may be carried out by a conventional method, and may further include other steps that are conventionally carried out.

[0085] [Cured film] Next, a cured film formed using the curable resin composition of the present invention will be described. The curable resin composition of the present invention can form a cured film by irradiating (exposing) it with active energy rays. Specifically, for example, it is preferable to form a cured film by applying the curable resin composition to a substrate, drying it, and irradiating (exposing) the coated surface with active energy rays. Thus, the cured film formed by the curable resin composition also constitutes one aspect of the present invention. The shape of the cured film is not particularly limited, and may be a molded product such as a plate, sheet, film, or fiber. When the coated ZrO2 particles or coated SiO2 particles are uniformly dispersed, transparency is further increased. Specifically, the transmittance of light with a wavelength of 400 nm at a thickness of 100 μm can be 70% or more, preferably 75% or more, and more preferably 80% or more. The haze value is preferably 1.1% or less, more preferably 1.0% or less, and even more preferably 0.9% or less. Thus, the cured film of the present invention preferably has high transparency. Therefore, even when a laminate including the cured film of the present invention is used in a touch panel, the display performance is not impaired, and clear images can be displayed. When a predetermined amount of coated ZrO2 particles is contained (for example, the ZrO2 particles are 40% by mass to 90% by mass relative to 100% by mass of the cured film), the refractive index is also high. Specifically, the refractive index for light of 589 nm can be 1.5 or more, and preferably 1.6 or more. The upper limit of the refractive index may be, for example, about 1.8. The refractive index was measured by applying the curable resin composition to a slide glass with an applicator to a film thickness of 100 μm, and then irradiating the film with a high-pressure mercury lamp at 1000 mJ / cm under a nitrogen atmosphere. 2 The composition is cured by irradiating it with ultraviolet light of 589 nm wavelength to obtain a cured film, and then the refractive index of the resulting cured film is measured at 20°C using a refractometer (DR-M2, manufactured by Atago Co., Ltd.). The substrate to which the curable resin composition is applied is not particularly limited, and examples thereof include transparent glass substrates such as white plate glass, blue plate glass, and silica-coated blue plate glass; sheets, films, or substrates made of thermoplastic resins such as polyester, polycarbonate, polyolefin, polysulfone, ring-opening polymers of cyclic olefins, and hydrogenated products thereof; sheets, films, or substrates made of thermosetting resins such as epoxy resins and unsaturated polyester resins; metal substrates such as aluminum plates, copper plates, nickel plates, and stainless steel plates; ceramic substrates; semiconductor substrates having photoelectric conversion elements; and members made of various materials such as glass substrates having a colorant layer on their surface (LCD color filters). Furthermore, the substrates may be subjected to corona discharge treatment, ozone treatment, or chemical treatment using a silane coupling agent, etc., as necessary.

[0086] The method for applying the curable resin composition to a substrate is not particularly limited, and examples thereof include spin coating, slit coating, roll coating, and cast coating, and any of these methods can be preferably used.

[0087] The coating film after application to the substrate can be dried using, for example, a hot plate, an IR oven, a convection oven, etc. Drying conditions are appropriately selected depending on the boiling point of the solvent component contained, the type of curable component, the film thickness, the performance of the dryer, etc., but typically, drying is preferably performed at a temperature of 50 to 160°C for 10 to 300 seconds.

[0088] Examples of light sources for the active energy rays include lamp light sources such as xenon lamps, halogen lamps, tungsten lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, medium-pressure mercury lamps, low-pressure mercury lamps, carbon arcs, and fluorescent lamps, and laser light sources such as argon ion lasers, YAG lasers, excimer lasers, nitrogen lasers, helium cadmium lasers, and semiconductor lasers. Examples of the exposure system include the proximity system, mirror projection system, and stepper system, with the proximity system being preferred. In the step of irradiating with active energy rays, depending on the application, the active energy rays may be irradiated through a predetermined mask pattern. In this case, the exposed area is cured, and the cured area is made insoluble or hardly soluble in a developer.

[0089] If necessary, after the active energy ray irradiation step, a step of developing the film with a developer to remove unexposed areas and form a pattern (also referred to as a "developing step") may be carried out, whereby a patterned cured film can be obtained. The development treatment in the above-mentioned development step can be carried out usually at a development temperature of 10 to 50° C. by a method such as immersion development, spray development, brush development, or ultrasonic development. In order to faithfully transfer the fine circuit pattern of the photomask onto the resist film, the active energy ray is preferably a short-wavelength ray such as a KrF excimer laser (wavelength 248 nm) or an ArF excimer laser (wavelength 193 nm), more preferably an ArF excimer laser. However, other ray sources such as g-rays (wavelength 436 nm), i-rays (wavelength 365 nm), X-rays (several nm to tens of nm), and electron beams (several hundred pm or less) may also be used. After exposure, the resist film is baked (pre-development bake, pre-baked) by subjecting it to a heat treatment at a relatively high temperature, for example, using a hot plate, an oven, or infrared irradiation, in order to reduce deformation of the resist pattern (resist sidewall shape). The resist film is then further developed to form a resist pattern. The bake temperature during the pre-development bake is not particularly limited, but is preferably within the range of 120°C to 250°C. The bake time is appropriately set depending on the bake temperature, the type of resist film, and the like. The resist film having a resist pattern formed thereon by development is subjected to post-baking (final baking) to evaporate and remove any residual developer or rinse solution remaining in or on the surface of the resist film and to strengthen adhesion to the substrate. The baking temperature and baking time during post-baking are not particularly limited, as long as they are set at a temperature at which the resist pattern shape does not soften or deform. Examples of developers that can be used in the development include alkaline developers such as organic alkaline aqueous solutions of tetramethylammonium hydroxide (TMAH) or choline, and inorganic alkaline aqueous solutions of potassium hydroxide or sodium hydroxide. When an alkaline aqueous solution is used as the developer, it is preferable to wash the resist film with water after development. As described above, the developer is not particularly limited as long as it dissolves the curable resin composition of the present invention, but an organic solvent or an alkaline aqueous solution is usually used, and a mixture thereof may also be used. Examples of organic solvents suitable for the developer include ether solvents and alcohol solvents. Specific examples include dialkyl ethers, ethylene glycol monoalkyl ethers, ethylene glycol dialkyl ethers, diethylene glycol dialkyl ethers, triethylene glycol dialkyl ethers, alkyl phenyl ethers, aralkyl phenyl ethers, diaromatic ethers, isopropanol, and benzyl alcohol.

[0090] The alkaline aqueous solution may contain, in addition to the alkaline agent, surfactants, organic solvents, buffers, dyes, pigments, etc., as necessary. In this case, examples of the organic solvent include the organic solvents suitable for the developer described above. Examples of the alkaline agent include sodium silicate, potassium silicate, sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium triphosphate, sodium diphosphate, carbonate, Examples of the alkali include inorganic alkali agents such as sodium, potassium carbonate, and sodium hydrogen carbonate; and amines such as trimethylamine, diethylamine, isopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, tetramethylammonium hydroxide, and tetraethylammonium hydroxide, which may be used alone or in combination of two or more. Examples of the surfactant include nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, sorbitan acid alkyl esters, and monoglyceride alkyl esters; anionic surfactants such as alkylbenzenesulfonates, alkylnaphthalenesulfonates, alkyl sulfates, alkylsulfonates, and sulfosuccinate salts; and amphoteric surfactants such as alkylbetaines and amino acids, which may be used alone or in combination of two or more.

[0091] As described above, a post-curing step (post-baking) may be carried out after the development step. The post-curing step is carried out by using a light source such as a high-pressure mercury lamp at a dose of, for example, 0.5 to 5 J / cm. 2 and a step of post-heating at a temperature of, for example, 60 to 260° C. for 10 seconds to 120 minutes. By carrying out such a post-curing step, it is possible to further increase the hardness and adhesion of the patterned cured film. The cured film thus obtained preferably has a film thickness of 0.1 to 20 μm, which satisfies the demand for low profile components and displays using the cured film. The film thickness is more preferably 0.5 to 10 μm, and even more preferably 0.5 to 8 μm. [Uses of curable resin composition] As described above, the curable resin composition of the present invention provides a cured product (cured film) that has excellent adhesion and developability, a high refractive index, sufficient surface hardness, and stable electrical properties. Therefore, the cured product (cured film) formed from such a curable resin composition is preferably used in a wide variety of applications, such as components for various display devices, such as liquid crystal, organic electroluminescence (EL), quantum dot, and micro LED liquid crystal displays, solid-state imaging devices, and touch panel display devices, as well as components for various optical materials and electrical and electronic devices, such as black matrices, photospacers, black column spacers, inks, printing plates, printed wiring boards, semiconductor devices, photoresists, insulating films, films, and organic protective films. Among these, the curable resin composition is preferably used in color filters used in liquid crystal displays and solid-state imaging devices, and touch panel display devices. It is particularly suitable to use the curable resin composition to form protective films (e.g., protective films for color filters, protective films for touch panel display devices) and insulating films (e.g., insulating films for touch panel display devices) for these various display devices. This makes it possible to sufficiently improve the reliability of the display quality and imaging quality of various display devices to a degree that can fully meet recent demands for higher performance. Thus, one preferred embodiment of the present invention is one in which the curable resin composition is a curable resin composition for forming a protective film or an insulating film. The present invention also includes a cured film formed from the curable resin composition, a member for an optical material such as a member for a display device having the cured film, and an optical material for a display device or the like having the cured film.

[0092] A particularly preferred embodiment of a display device member and a display device has a cured film formed from the curable resin composition. The cured film formed from the curable resin composition is stable and has excellent adhesion, high hardness, high smoothness, and high transmittance. Therefore, it is particularly suitable as a transparent member and is very useful as a protective film or insulating film in various display devices. The display device is not particularly limited, but suitable examples include liquid crystal display devices, solid-state imaging devices, and touch panel display devices. As touch panel display devices, capacitance type devices are particularly preferred. The display device member may be a film-like single-layer or multi-layer member composed of the cured film, or may be a member in which another layer is further combined with the single-layer or multi-layer member, or may be a member containing the cured film in its structure (for example, a color filter, etc.).

[0093] [Preferred Use] The curable resin composition of the present invention exhibits outstanding dispersibility and storage stability despite containing metal oxide particles with an average particle size of less than 30 nm. Applications requiring high dispersibility include, for example, resist applications, optical applications, coating applications, and adhesive applications. The composition is suitable for optical lenses, pressure-sensitive adhesives for optical films, adhesives for optical films, nanoimprint resin compositions, microlens arrays, anti-reflection layers used in transparent electrodes, anti-reflection films and anti-reflection agents, surface coatings for optical lenses, light extraction layers for organic electroluminescence (EL) lenses, various hard coating materials, TFT planarization films, color filter overcoats, and various protective films such as anti-reflection films, as well as optical materials such as optical filters, insulating films for touch sensors, insulating films for TFTs, photospacers for color filters, and protective films for touch panels. In particular, due to its outstanding dispersibility, high refractive index, high hardness, and high dielectric constant, the composition is suitable for use in optical lenses, surface coatings for optical lenses, interlayer insulating films, insulating films for touch sensors, insulating films for TFTs, and protective films for touch panels.

[0094] When the metal oxide particles are ZrO particles, the curable resin composition is suitable for use in high-refractive-index optical materials (preferably for forming high-refractive-index transparent films), and preferred applications include those described in paragraphs 0072 to 0092 of Japanese Patent No. 6251478. For example, by taking advantage of its high dielectric constant, it can be applied to semiconductor gate insulating films and capacitor insulating films for memories such as DRAM. Furthermore, when used in coating applications such as hard coatings, hard coating materials obtained from the curable resin composition of the present invention are suitable for use in office automation equipment, communication devices such as mobile phones, household electrical appliances, interior and exterior parts for automobiles, exterior materials for furniture, plastic lenses, cosmetic containers, beverage containers, displays such as organic electroluminescence (EL) displays, touch panels for home appliances, sinks, washbasins, and even show windows and window glass. [Example]

[0095] The present invention will be described in more detail below with reference to examples. However, the following examples do not limit the present invention, and all modifications and variations within the scope of the present invention are included in the technical scope of the present invention. The present invention will be specifically illustrated by examples, comparative examples, and property evaluations. In the examples and comparative examples, % means % by mass, and parts means parts by mass, unless otherwise specified. In the following synthesis examples and preparation examples, various physical properties were evaluated as follows. [Evaluation method] Weight average molecular weight (Mw) The weight average molecular weight (Mw) was measured by GPC (gel permeation chromatography) using polystyrene as a standard substance and tetrahydrofuran as an eluent on an HLC-8320GPC (manufactured by Tosoh Corporation) column: TSKgel SuperHZM-M (manufactured by Tosoh Corporation). (2) Acid value (AV) 3 g of the polymer solution was precisely weighed and dissolved in a mixed solvent of 90 g of acetone and 10 g of water, and titrated using a 0.1 N KOH aqueous solution as a titrant. The titration was carried out using an automatic titrator (product name: COM-1700A, manufactured by Hiranuma Sangyo Co., Ltd.), and the acid value per 1 g of solid content (mg KOH / g) was calculated from the acid value of the solution and the solid content of the solution. (3) Solid content (NV) Approximately 1 g of the polymer solution was weighed into an aluminum cup, dissolved in approximately 3 g of acetone, and then air-dried at room temperature. The solution was then dried in a hot air dryer (product name: PHH-101, manufactured by Espec Corporation) at 140°C under vacuum for 1.5 hours, cooled in a desiccator, and weighed. The solid content (% by mass) of the polymer solution was calculated from the mass loss. (4) Identification of the crystalline state of metal oxide particles The crystalline state of the metal oxide was identified using an X-ray diffractometer (Rigaku Corporation, RINT-TTRIII). (5) Number average primary particle size of metal oxide particles The number average primary particle size of the metal oxide particles was measured by observing them with an ultra-high resolution field emission scanning electron microscope (S-4800, manufactured by Hitachi High-Technologies Corporation). The metal oxide particles were observed at a magnification of 150,000 times, and the length of each of 100 randomly selected particles in the long axis direction was measured, and the average value was taken as the number average primary particle size. (6) Measurement of mass loss rate Using a TG-DTA (thermogravimetric-differential thermal analysis) device, the surface-modified metal oxide particles were heated in an air atmosphere from room temperature to 800°C at a rate of 10°C / min, and the mass loss rate of the particles was measured. This mass loss rate allows us to determine the proportion of the compound that has surface-modified the metal oxide particles and the proportion of the metal oxide particles. (7) 1H-NMR Measurement The coated zirconium oxide particles were dispersed in deuterated chloroform to prepare a measurement sample, and measurements were performed using a Varian "Unity Plus" (resonance frequency: 400 MHz, number of accumulations: 16). The molar ratio of each compound was determined based on the integral ratio of the peaks of the following chemical shifts (based on tetramethylsilane):

[0096] i) 2-Ethylhexanoic acid (1.0-0.5 ppm:6H) ii) Carboxylate derived from 2-ethylhexanoic acid (1.0-0.5 ppm:6H) iii) 2-Acryloyloxyethyl succinate (6.7-5.7 ppm: 3H, 4.5-4.0 ppm: 4H) iv) 3-methacryloxypropyltrimethoxysilane (6.5-5.5 ppm: 2H, 4.5-4.0 ppm: 2H, 4.0-3.5 ppm: 9H, 1.0-0.5 ppm: 2H) (8) X-ray fluorescence analysis The Zr content and Si content in the coated zirconium oxide particles were measured using an X-ray fluorescence analyzer (ZSX Primus II, manufactured by Rigaku Corporation).

[0097] (9) Adhesion of the cured film The obtained curable resin composition was applied to an alkali-free glass substrate (10 cm × 10 cm, manufactured by Geomatec Co., Ltd.) by spin coating, and after heat treatment (90°C for 3 minutes), it was irradiated with 60 mJ / cm using an ultra-high pressure mercury lamp through a photomask with openings of 1-100 μm line width at a distance of 50 μm from the coating film. 2 (365 nm illuminance equivalent) After that, the glass substrate with the cured film was immersed in 40 g of 2.38% tetramethylammonium hydroxide aqueous solution for 20 seconds or 60 seconds to dissolve and remove the unexposed area, and the remaining exposed area was washed with pure water for 10 seconds to perform development. The cured film developed through the photomask as described above was observed using a surface roughness meter (manufactured by Ryoka Systems Co., Ltd., product name "VertScan2.0"), and the minimum line width of the photomask remaining on the glass substrate was read.

[0098] In the above development, the conditions were selected based on the conditions under which the unexposed coating film was completely dissolved, and also to make it easier to confirm the effect of the presence or absence of metal oxide particles. For example, when no clear difference in adhesion of the cured film was observed between the presence and absence of metal oxide particles after immersion in a 2.38% aqueous solution of tetramethylammonium hydroxide for 20 seconds, immersion was continued for 60 seconds. (10) Residual rate of cured film The glass substrate with the cured film obtained in (9) above was heat-treated (230°C for 30 minutes), and then the film thickness before and after heating was measured, and the remaining film ratio was calculated using the following formula. Remaining film rate = (film thickness after heating / film thickness before heating) x 100 (formula) (11) Dispersibility 20 mL of the metal oxide particle dispersion was poured into a test tube with an outer diameter of 30 mm and left upright in an atmosphere at 25°C for 24 hours. After leaving it, the bottom of the test tube was observed, and evaluation was performed by rating it as ◯ if no precipitate was found and × if precipitate was found. (12) Transparency The composition described in detail below was applied to a 100-micron-thick PET film (product name: Cosmoshine AS4300, manufactured by Toyobo Co., Ltd.) using a bar coater #20, dried at 80°C for 5 minutes, and then irradiated with 1000 mJ / cm 2 using a high-pressure mercury lamp. 2 The coating was cured by irradiating it with ultraviolet light to obtain a cured product (dry film thickness: 5 microns). The haze in the thickness direction of the produced cured product was measured using a turbidity meter (NDH7000 manufactured by Nippon Denshoku Industries Co., Ltd.). 〇: 1% or less, △: 1%~50%, ×: 50% or more

[0099] The following zirconia particle dispersions were used: Production Examples 1 and 2 (Preparation of Zirconia Particle Dispersion 1) Manufacturing Example 1 Coated zirconium oxide nanoparticles (coated ZrO) coated with 2-ethylhexanoic acid and / or carboxylates derived from 2-ethylhexanoic acid 2 Production of particles A zirconium 2-ethylhexanoate mineral spirit solution (782 g, zirconium 2-ethylhexanoate content: 44% by mass, manufactured by Daiichi Kigenso Kagaku Kogyo Co., Ltd.) was mixed with pure water (268 g). The resulting mixture was placed in an autoclave equipped with a stirrer, and the atmosphere inside the autoclave was replaced with nitrogen gas. The mixture was then heated to 180°C and maintained at that temperature for 16 hours (the pressure inside the autoclave was 0.94 MPa) to react and produce zirconium oxide particles. The reacted mixture was then removed, and the precipitate that had accumulated at the bottom was filtered out, washed with acetone, and then dried. The dried precipitate (100 g) was dispersed in toluene (800 mL), resulting in a cloudy solution. Next, as a purification step, the mixture was again filtered using quantitative filter paper (manufactured by Advantec Toyo Co., Ltd., No. 5C) to remove coarse particles from the precipitate. Furthermore, the filtrate was concentrated under reduced pressure to remove the toluene, and white zirconium oxide nanoparticles (coated ZrO2 particles) were recovered. When the crystalline structure of the obtained coated ZrO2 particles was confirmed, diffraction lines belonging to tetragonal and monoclinic crystals were detected. Based on the intensity of the diffraction lines, the ratio of tetragonal to monoclinic crystals was 54 / 46, and the particle diameter (crystallite diameter) was 5 nm. The average particle size (number average primary particle size) of the obtained coated ZrO2 particles measured with an electron microscope was 12 nm. Furthermore, when the obtained coated ZrO2 particles were analyzed by infrared absorption spectroscopy, absorption derived from CH and absorption derived from COOH were confirmed. This absorption is thought to be due to 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid coating the coated zirconium oxide particles. Furthermore, the mass loss rate of the coated ZrO2 particles, measured according to the above-mentioned "(6) Measurement of mass loss rate," was 12% by mass. Therefore, it was found that the amount of 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid coating the coated zirconium oxide particles was 12% by mass of the entire coated zirconium oxide particles. Manufacturing Example 2 Zirconium oxide nanoparticles (coated ZrO) coated with 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid, 2-acryloyloxyethyl succinate, and 3-methacryloxypropyltrimethoxysilane were prepared. 2 Production of particles 1) The coated ZrO2 particles (10 g) obtained above were dispersed in methyl isobutyl ketone (40 g) to prepare a cloudy white slurry. The solution was added with 3-methacryloxypropyltrimethoxysilane (2.0 g, Shin-Etsu Chemical Co., Ltd., KBM-503) as a surface treatment agent and water (0.9 g), and heated under reflux at 80 °C for 1 hour to obtain a transparent dispersion. The temperature was then lowered to 50 °C, after which 2-acryloyloxyethyl succinate (1.8 g) was added and stirred for 30 minutes. Next, n-hexane was added to aggregate the dispersed particles, causing the solution to become cloudy. The aggregated particles were separated from the cloudy solution using filter paper and then dried by heating at room temperature to prepare zirconium oxide nanoparticles (coated ZrO2 particles 1) coated with 2-ethylhexanoic acid and / or a carboxylate derived from 2-ethylhexanoic acid, 2-acryloyloxyethyl succinate, and 3-methacryloxypropyltrimethoxysilane. The mass loss rate of the coated zirconium oxide nanoparticles when heated to 800°C at a rate of 10°C / min in an air atmosphere was measured by TG-DTA (thermogravimetry-differential thermal analysis) of the obtained coated ZrO2 particles 1, and the loss rate was 17% by mass. This confirmed that the organic content of the coated zirconium oxide nanoparticles was 17% by mass. Furthermore, the nanoparticles were analyzed using an X-ray fluorescence analyzer to measure the Zr and Si contents, which revealed that the amount of 3-methacryloxypropyltrimethoxysilane was 8 mass % relative to the coated zirconium oxide. The obtained coated ZrO2 particles 1 were dispersed in deuterated chloroform to prepare a measurement sample, which was then analyzed by H-NMR. The results showed that the molar ratio of 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid, 3-methacryloxypropyltrimethoxysilane, and 2-acryloyloxyethyl succinate was 27:35:38. Taking into consideration the above analytical results by TG-DTA, X-ray fluorescence analysis, and 1H-NMR, it was found that 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid, 3-methacryloxypropyltrimethoxysilane, and 2-acryloyloxyethyl succinate accounted for 3 mass%, 8 mass%, and 7 mass%, respectively, of the total amount of the coated zirconium oxide particles (100 mass%). The coated ZrO2 particles 1 (7 g) obtained above, methyl ethyl ketone (3 g), and DISPER BYK-111 (0.14 g) were mixed and stirred uniformly to obtain zirconia particle dispersion 1. The number average primary particle diameter of the coated ZrO2 particles 1 measured with an electron microscope was 12 nm. Production Example 3 (Preparation of Zirconia Particle Dispersion 2) Zirconium oxide nanoparticles (coated ZrO) coated with 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid and 2-acryloyloxyethyl succinate 2 Production of particles 2) The coated zirconium oxide nanoparticles (10 g) obtained in Production Example 1 and 2-acryloyloxyethyl succinate (1.5 g) were mixed and stirred in propylene glycol monomethyl ether acetate (12 g, hereinafter referred to as "PGMEA") until uniformly dispersed. Next, n-hexane (36 g) was added to aggregate the dispersed particles, making the solution cloudy. The aggregated particles were separated from the cloudy solution using filter paper. The separated aggregated particles were then added to n-hexane (36 g) and stirred for 10 minutes. After that, the aggregated particles were separated using filter paper. The obtained particles were dried in vacuum at room temperature to prepare zirconium oxide nanoparticles (coated ZrO2 particles 2) surface-treated with 2-ethylhexanoic acid and / or a carboxylate derived from 2-ethylhexanoic acid and 2-acryloyloxyethyl succinate. The obtained coated ZrO2 particles 2 were dispersed in deuterated chloroform to prepare a measurement sample, which was then analyzed by H-NMR. As a result, it was found that the molar ratio of 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid to 2-acryloyloxyethyl succinate was 24:76. Furthermore, the mass loss rate of the coated ZrO2 particles 2, measured according to the above-mentioned "(6) Measurement of mass loss rate," was 18% by mass. Therefore, it was found that the amount of 2-ethylhexanoic acid and / or carboxylate derived from 2-ethylhexanoic acid, and 2-acryloyloxyethyl succinate coating the coated zirconium oxide particles was 18% by mass of the entire coated zirconium oxide particles. The coated ZrO2 particles 2 (7 g) obtained above, methyl ethyl ketone (3 g), and DISPER BYK-111 (manufactured by BYK-Chemie Japan, 0.14 g) were mixed and stirred uniformly to obtain zirconia particle dispersion 2. The number average primary particle diameter of the coated ZrO2 particles 2 measured with an electron microscope was 12 nm. Production Example 4 (Preparation of Zinc Oxide Particle Dispersion 3) The zinc oxide (ZnO2) particles used were powder with a primary particle diameter of 35 nm (TAYCA, MT-100TV). Production Example 5 (Preparation of Silica Particle Dispersion 4) Silica (SiO2) particles were used in a fine particle dispersion with a primary particle diameter of 12 nm (dispersion medium: propylene glycol monomethyl ether (Nissan Chemicals, PGM-AC-2140Y)).

[0100] The following alkali-soluble polymers were used: Production Example 6 (Production of alkali-soluble polymer 1) A separable flask equipped with a condenser was charged with 637 parts of propylene glycol monomethyl ether acetate (PGMEA) as a reaction vessel, and after purging with nitrogen, the temperature was raised to 90°C. Meanwhile, 120 parts of N-benzylmaleimide, 125 parts of acrylic acid, and 223 parts of PGMEA were mixed in dropping vessel 1. Furthermore, 235 parts of vinyltoluene (m- and p-vinyltoluene, 60:40 mixture), 9.6 parts of t-butylperoxy-2-ethylhexanoate (Perbutyl O, product name, manufactured by NOF Corporation), and 13.4 parts of n-dodecyl mercaptan were mixed in dropping vessel 2. While maintaining the reaction temperature at 90°C, the mixture was added dropwise from dropping vessels 1 and 2 to the reaction vessel at a constant rate over 4.0 hours. After completion of the dropwise addition, the temperature was maintained at 90°C for 30 minutes, after which 2.4 parts of Perbutyl O were added, and the reaction was continued at 90°C for another 30 minutes. The reaction temperature was then raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 76 parts of glycidyl methacrylate, 0.8 parts of 6-t-butyl-2,4-xylenol, and 1.7 parts of triethylamine were added, and the temperature was raised to 110°C while bubbling a nitrogen-air mixed gas adjusted to an oxygen concentration of 7%, and the reaction was carried out for 12 hours. After cooling to room temperature, polymer solution 1 was obtained. The various physical properties of the obtained polymer solution 1 were measured, and the weight average molecular weight was 12,800, the solid content was 32.1%, the acid value per solid content determined by titration was 129 mg KOH / g, and the double bond equivalent was 1,073 g / mol. Production Example 7 (Production of alkali-soluble polymer 2) A separable flask equipped with a condenser was charged with 394 parts of PGMEA and 394 parts of propylene glycol monomethyl ether (PGME) as a reaction vessel, and the temperature was raised to 90°C under a nitrogen atmosphere. Meanwhile, 251 parts of cyclohexyl methacrylate, 5 parts of methyl methacrylate, 50 parts of N-benzylmaleimide, 194 parts of methacrylic acid, 10 parts of Perbutyl O, 25 parts of PGMEA, and 25 parts of PGME were mixed in dropping vessel 1. 30 parts of n-dodecyl mercaptan, 45 parts of PGMEA, and 45 parts of PGME were mixed in dropping vessel 2. Each was continuously fed over 3 hours. After the completion of the dropwise addition, the temperature was maintained at 90°C for 30 minutes, after which 2.4 parts of Perbutyl O were added, and the reaction was continued at 90°C for another 30 minutes. The reaction temperature was then raised to 115°C, and the reaction was continued for 1.5 hours. After cooling to room temperature, 123 parts of glycidyl methacrylate, 0.9 parts of 6-t-butyl-2,4-xylenol, and 1.9 parts of triethylamine were added, and the temperature was raised to 110°C while bubbling a nitrogen-air mixed gas adjusted to an oxygen concentration of 7%, and the reaction was carried out for 2 hours. Thereafter, the temperature was raised to 115°C and the reaction was carried out for 5 hours, at which point the reaction was completed and the mixture was cooled to room temperature, yielding polymer solution 2. The various physical properties of the obtained polymer solution 2 were measured, and the weight average molecular weight was 8100, the solid content was 38.5%, the acid value per solid content determined by titration was 131 mgKOH / g, and the double bond equivalent was 754 g / mol. Production Example 8 (Production of alkali-soluble polymer 3) A separable flask equipped with a condenser was charged with 449 parts of PGMEA and 91 parts of PGME as a reaction vessel, and the temperature was raised to 90 ° C under a nitrogen atmosphere. Meanwhile, 198 parts of cyclohexyl methacrylate, 5 parts of methyl methacrylate, 150 parts of N-benzylmaleimide, 148 parts of methacrylic acid, 10 parts of Perbutyl O, 213 parts of PGMEA, and 91 parts of PGME were mixed in dropping vessel 1. 3.5 parts of n-dodecyl mercaptan and 42 parts of PGMEA were mixed in dropping vessel 2. Each was continuously fed over 3 hours. After maintaining the temperature at 90 ° C for 30 minutes, 2.5 parts of Perbutyl O were added, and the reaction was continued at 90 ° C for another 30 minutes. The temperature was then raised to 115 ° C, and polymerization was continued for 1.5 hours. After cooling to room temperature, 41 parts of glycidyl methacrylate, 0.8 parts of 6-t-butyl-2,4-xylenol, and 1.6 parts of triethylamine were added, and the temperature was raised to 110°C while bubbling a nitrogen-air mixed gas adjusted to an oxygen concentration of 7%, and the reaction was carried out for 1 hour.The temperature was then raised to 115°C and the reaction was carried out for 6 hours, at which point the reaction was completed and the mixture was cooled to room temperature, yielding polymer solution 3. The various physical properties of the obtained polymer solution 3 were measured, and the weight average molecular weight was 18,900, the solid content was 34.7%, the acid value per solid content determined by titration was 149 mg KOH / g, and the double bond equivalent was 1,884 g / mol. Production Example 9 (Production of alkali-soluble polymer 4) A separable flask equipped with a condenser was charged with 557 parts of PGMEA and 247 parts of PGME as a reaction vessel, and the temperature was raised to 90 ° C under a nitrogen atmosphere. Meanwhile, 275 parts of benzyl methacrylate, 5 parts of methyl methacrylate, 50 parts of N-benzylmaleimide, 170 parts of methacrylic acid, 10 parts of Perbutyl O, 35 parts of PGMEA, and 15 parts of PGME were mixed in dropping vessel 1. 24 parts of n-dodecyl mercaptan, 67 parts of PGMEA, and 29 parts of PGME were mixed in dropping vessel 2. Each was continuously fed over 3 hours. After maintaining the temperature at 90 ° C for 30 minutes, 2.5 parts of Perbutyl O were added, and the reaction was continued at 90 ° C for another 30 minutes. The temperature was then raised to 115 ° C, and polymerization was continued for 1.5 hours. After cooling to room temperature, 83 parts of glycidyl methacrylate, 0.90 parts of 6-t-butyl-2,4-xylenol, and 1.7 parts of triethylamine were added, and the temperature was raised to 110°C while bubbling a nitrogen-air mixed gas adjusted to an oxygen concentration of 7%, and the reaction was carried out for 1 hour. Thereafter, the temperature was raised to 115°C and the reaction was carried out for 8 hours, at which point the reaction was completed and the mixture was cooled to room temperature, yielding polymer solution 4. The various physical properties of the obtained polymer solution 4 were measured, and the weight average molecular weight was 7,600, the solid content was 36.0%, the acid value per solid content determined by titration was 142 mg KOH / g, and the double bond equivalent was 1,049 g / mol. Production Example 10 (Production of Alkali-Soluble Polymer 5) A separable flask equipped with a condenser was charged with 513 parts of PGMEA and 513 parts of PGME as a reaction vessel, and the temperature was raised to 90 ° C under a nitrogen atmosphere. Meanwhile, 270 parts of cyclohexyl methacrylate, 5 parts of methyl methacrylate, 50 parts of N-benzylmaleimide, 175 parts of acrylic acid, 10 parts of Perbutyl O, 25 parts of PGMEA, and 25 parts of PGME were mixed in dropping vessel 1. 30 parts of n-dodecyl mercaptan, 45 parts of PGMEA, and 45 parts of PGME were mixed in dropping vessel 2. Each was continuously fed over 3 hours. After maintaining the temperature at 90 ° C for 30 minutes, 2.5 parts of Perbutyl O were added, and the reaction was continued at 90 ° C for another 30 minutes. The temperature was then raised to 115 ° C, and polymerization was continued for 1.5 hours. After cooling to room temperature, 148 parts of glycidyl methacrylate, 1.0 part of 6-t-butyl-2,4-xylenol, and 1.9 parts of triethylamine were added, and the temperature was raised to 110°C while bubbling a nitrogen-air mixed gas adjusted to an oxygen concentration of 7%, and the reaction was carried out for 1 hour. Thereafter, the temperature was raised to 115°C and the reaction was carried out for 7 hours, at which point the reaction was completed and the mixture was cooled to room temperature to obtain polymer solution 5. The various physical properties of the obtained polymer solution 5 were measured, and the weight average molecular weight was 6,500, the solid content was 34.4%, the acid value per solid content determined by titration was 132 mg KOH / g, and the double bond equivalent was 654 g / mol. Production Example 11 (Production of Alkali-Soluble Polymer 6) A separable flask equipped with a condenser was charged with 633 parts of PGMEA and 322 parts of PGME as a reaction vessel, and the temperature was raised to 90 ° C under a nitrogen atmosphere. Meanwhile, 189 parts of cyclohexyl methacrylate, 217 parts of 2-ethylhexyl acrylate, 6 parts of methyl methacrylate, 30 parts of N-benzylmaleimide, 158 parts of acrylic acid, 12 parts of Perbutyl O, 151 parts of PGMEA, and 44 parts of PGME were mixed in dropping vessel 1. 6 parts of n-dodecyl mercaptan and 54 parts of PGMEA were mixed in dropping vessel 2. Each was continuously fed over 3 hours. After maintaining the temperature at 90 ° C for 30 minutes, 3 parts of Perbutyl O were added, and the reaction was continued at 90 ° C for another 30 minutes. The temperature was then raised to 115 ° C, and polymerization was continued for 1.5 hours. After cooling to room temperature, 237 parts of glycidyl methacrylate, 1.3 parts of 6-t-butyl-2,4-xylenol, 2.5 parts of triethylamine, 25 parts of PGMEA, and 11 parts of PGME were added, and the temperature was raised to 110°C while bubbling a nitrogen-air mixed gas adjusted to an oxygen concentration of 7%, and the reaction was carried out for 1 hour. The temperature was then raised to 115°C and the reaction was carried out for 12 hours, at which point the reaction was completed and the mixture was cooled to room temperature to obtain polymer solution 6. The various physical properties of the obtained polymer solution 6 were measured, and the weight average molecular weight was 15,600, the solid content was 39.2%, the acid value per solid content determined by titration was 43 mgKOH / g, and the double bond equivalent was 508 g / mol. Production Example 12 (Production of Alkali-Soluble Polymer 7) A separable flask equipped with a condenser was charged as a reaction vessel with 533 parts of PGMEA and 222 parts of PGME, and the temperature was raised to 90° C. under a nitrogen atmosphere. Separately, a monomer dropping vessel containing 42 parts by mass of dimethyl-2,2′-[oxybis(methylene)]bis-2-propenoate, 252 parts by mass of cyclohexyl methacrylate, 8 parts by mass of methyl methacrylate, 119 parts by mass of methacrylic acid, and 8 parts by mass of perbutyl O was prepared by thoroughly stirring and mixing, and a chain transfer agent dropping vessel containing 7 parts by mass of n-dodecanethiol and 43 parts by mass of PGMEA was prepared by thoroughly stirring and mixing. After the temperature of the reactor stabilized at 90°C, dropwise addition was initiated from the monomer dropping tank and the chain transfer agent dropping tank. The dropwise addition was carried out over 135 minutes, while maintaining the temperature at 90°C. Sixty minutes after the end of the dropwise addition, the temperature was raised to 110°C and maintained at 110°C for 3 hours. After the internal temperature was cooled to room temperature, a gas inlet tube was attached to the separable flask, and bubbling of a 5 / 95 (v / v) oxygen / nitrogen mixed gas began. Next, 69 parts of glycidyl methacrylate, 0.3 parts of 6-t-butyl-2,4-xylenol, and 1.5 parts of triethylamine were charged to the reactor and reacted at 110°C for 12 hours. Then, 96 parts of PGMEA was added and the mixture was cooled to room temperature to obtain Polymer Solution 7. The various physical properties of the obtained polymer solution 7 were measured, and the weight average molecular weight was 11,800, the solid content was 36.1%, the acid value per solid content determined by titration was 118 mg KOH / g, and the double bond equivalent was 1,017 g / mol. Production Example 13 (Production of alkali-soluble polymer 8) A separable flask equipped with a condenser was used as a reaction vessel, and 358 parts of PGMEA and 153 parts of PGME were charged and heated to 90° C. under a nitrogen atmosphere. Separately, a monomer dropping vessel containing 37 parts by mass of dimethyl-2,2′-[oxybis(methylene)]bis-2-propenoate, 201 parts by mass of cyclohexyl methacrylate, 69 parts by mass of methyl methacrylate, 58 parts by mass of methacrylic acid, and 7 parts by mass of perbutyl O was prepared with thorough stirring. A chain transfer agent dropping vessel containing 5 parts by mass of n-dodecanethiol and 50 parts by mass of PGMEA was prepared with thorough stirring. After the temperature of the reaction vessel stabilized at 90°C, dropwise addition was initiated from the monomer dropping vessel and the chain transfer agent dropping vessel. The dropping was carried out over 135 minutes, each while maintaining the temperature at 90°C. 60 minutes after the end of the dropping, the temperature was raised to 110°C and maintained at 110°C for 3 hours. Then, 96 parts of PGMEA was added and the mixture was cooled to room temperature, yielding polymer solution 8. The various physical properties of the obtained polymer solution 8 were measured, and it was found that the weight average molecular weight was 12,200, the solid content was 34.5%, and the acid value per solid content determined by titration was 115 mgKOH / g.

[0101] (Examples 1 to 11 and Comparative Examples 1 to 8) The metal oxide particle dispersion obtained in the above Production Example, an alkali-soluble polymer, a commercially available polymerizable monomer, and a photopolymerization initiator were mixed to produce curable resin compositions K1 to K9 and S1 to S6. The composition (mass ratio) is as follows. PGMEA was added as a solvent to adjust the solid content. In terms of solid content, Alkali-soluble polymer / dipentaerythritol hexaacrylate / metal oxide particles / Irgacure 907 (BASF) = 22.5 / 22.5 / 45 / 5 Thereafter, the adhesion and film remaining rate of the curable resin composition were evaluated according to the above-mentioned "(9) Adhesion of cured film" and "(10) Film remaining rate of cured film." The evaluation results for the obtained curable resin composition and the cured film thereof are shown in Tables 1 and 2.

[0102] [Table 1]

[0103] [Table 2] (Examples 12 to 19, and Comparative Example 9) The metal oxide particle dispersion obtained in the above Production Example, an alkali-soluble polymer, and a commercially available photopolymerization initiator were mixed together to produce curable resin compositions K10 to K17 and S7. The composition (mass ratio) is as follows. MEK was added as a solvent to adjust the solid content. In terms of solid content, Alkali-soluble polymer / metal oxide particles / Irgacure 907 (BASF) =0.53 / 2.1 / 0.016 After that, an evaluation was conducted according to the above-mentioned "(11) Dispersibility" and "(12) Transparency." In the above evaluation, when dipentaerythritol hexaacrylate was further added, the same evaluation results were obtained. The results are shown in Table 3.

[0104] [Table 3] The abbreviations are as follows: Irgacure907: Irgacure907, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one DPHA: Dipentaerythritol hexaacrylate MEK: Methyl ethyl ketone PGMEA: Propylene glycol monomethyl ether acetate TMAH: tetramethylammonium hydroxide BYK-111: Phosphate ester dispersant with phosphate groups at both ends of the copolymer A comparison between the Examples (Table 1) and Comparative Examples (Table 2) confirmed the superiority of the curable resin composition of the present invention. In particular, a comparison between Example 4 and Comparative Example 4, which were performed under strict development conditions, confirmed that the addition of ZrO2 particles enables the formation of a cured film with excellent adhesion without peeling. Furthermore, alkali-soluble polymers containing N-substituted maleimide monomer units or dialkyl-2,2'-(oxydimethylene)diacrylate monomer units were effective in improving the dispersibility of metal oxide particles and the adhesion of cured films obtained by curing compositions containing them. Comparisons between Example 1 and Example 8, and between Example 9 and Example 11, confirmed that a cured film with high adhesion can be obtained by using an alkali-soluble polymer that has a side chain double bond and a polymer with a small double bond equivalent. Note that the smaller the double bond equivalent, the greater the amount of polymerizable double bonds in the side chain, which can increase the crosslink density, making it easier to obtain a cured film with a high refractive index. A comparison between Example 2 and Example 10 shows that the combined use of ZrO2 particles and SiO2 particles as metal oxide particles improves the adhesion and film remaining rate. A comparison between Example 1 and Example 6 showed that the use of metal oxide particles surface-treated with a silane coupling agent tended to result in a cured film with higher adhesion. The effect of controlling the number average primary particle size of metal oxide particles was confirmed from Table 3. Note that, although Table 3 confirms the compatibility of each component in a system that does not contain a polymerizable monomer, in Examples 12 to 19, when a polymerizable monomer such as DPHA is added, high dispersibility and transparency can be maintained. Figures 1 and 2 show the state of the glass substrate after alkali development of the exposed coating film. A grid-like pattern can be seen in the exposed area exposed through a photomask and the unexposed area protected by the photomask. As shown in Figures 1 and 2, a complete pattern was formed in the exposed area by curing the coating film, and there were no defects. In the unexposed area, the coating film was dissolved, and no undissolved residue was observed. It was confirmed that curable resin composition K1 produced a cured film with higher adhesion than K2, as the line width was 33 μm in Figure 1 and 58 μm in Figure 2. [Industrial Applicability]

[0105] The cured film formed from the curable resin composition of the present invention allows high definition to be realized, and optical materials such as display device members can be suitably used in the fields of optics and electric / electronics.

Claims

1. Zirconium dioxide particles having a number average primary particle diameter of less than 30 nm, which have been surface-modified with an organic compound having a carboxyl group, which is an organic acid, and a surface modifier including a phosphoric acid surfactant and / or a silane coupling agent; an alkali-soluble polymer having a monomer unit selected from N-substituted maleimide monomers consisting of N-cyclohexylmaleimide, N-phenylmaleimide, and N-benzylmaleimide, and having an acid value of 100 mgKOH / g or more and 250 mgKOH / g or less and a double bond equivalent of 400 g / mol to 1073 g / mol; and a curable resin composition for forming a high refractive index transparent film, the curable resin composition comprising a polymerizable monomer.

2. 2. The curable resin composition for forming a high refractive index transparent film according to claim 1, wherein the alkali-soluble polymer is a polymer further having a structural unit derived from (meth)acrylic acid.

3. 3. The curable resin composition for forming a high refractive index transparent film according to claim 1, wherein the alkali-soluble polymer is a polymer further having a structural unit derived from an alicyclic (meth)acrylate.

4. The curable resin composition for forming a high refractive index transparent film according to any one of claims 1 to 3, wherein the alkali-soluble polymer is a polymer further having a structural unit derived from an aromatic vinyl monomer.

5. 5. The curable resin composition for forming a high refractive index transparent film according to claim 1, wherein the alkali-soluble polymer is a polymer having a glass transition temperature of -10°C or higher and 80°C or lower.

6. The curable resin composition for forming a high refractive index transparent film according to any one of claims 1 to 5, wherein the alkali-soluble polymer is a polymer having a structural unit derived from at least one monomer selected from n-butyl (meth)acrylate, s-butyl (meth)acrylate, t-butyl (meth)acrylate, n-amyl (meth)acrylate, s-amyl (meth)acrylate, t-amyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, tridecyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclohexylmethyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, phenyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, and tricyclodecanyl (meth)acrylate.

7. The curable resin composition for forming a high refractive index transparent film according to any one of claims 1 to 6, further comprising silicon dioxide particles.

8. A curable resin composition for forming a high refractive index transparent film described in any one of claims 1 to 7, which is for forming an interlayer insulating film.

9. 9. The curable resin composition for forming a high refractive index transparent film according to claim 1, wherein the alkali-soluble polymer is a polymer having a weight average molecular weight of 5,000 or more and 8,100 or less.

10. The curable resin composition for forming a high refractive index transparent film according to any one of claims 1 to 9, further comprising a photopolymerization initiator.

11. 11. A method for producing a curable resin composition for forming a high refractive index transparent film according to claim 1, comprising the steps of: dispersing the zirconium dioxide particles in an organic solvent to obtain an organic solvent dispersion of zirconium dioxide particles; surface-modifying the zirconium dioxide particles with a surface modifier before, after, or during the step of obtaining the dispersion; and mixing the dispersion with an alkali-soluble polymer, a polymerizable monomer, and other components that may be contained as needed.

12. A cured film obtained by curing the curable resin composition for forming a high refractive index transparent film according to any one of claims 1 to 10.

13. A member for optical materials, comprising the cured film according to claim 12.

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