Resin composition

Abstract

A resin composition according to the present invention includes component (A-1) and component (C) or includes component (A-2), component (B), and component (C).　Component (A-1): A polymer that has a structural unit represented by formula (1), a structural unit represented by formula (2), and a structural unit represented by formula (3). Component (A-2): A polymer that has a structural unit represented by formula (1) and a structural unit represented by formula (3) (excluding component (A-1)). Component (B): A polymer that has a structural unit represented by formula (2) (excluding component (A-1)). Component (C): An organic solvent. (In formula (1) and formula (2), R0 is a hydrogen atom or a methyl group, Ar is an aromatic group that has at least two benzene rings and may have a heteroatom, R1 is a single bond or a C1–5 alkylene group, and R2 is a blocked isocyanate group.)

Description

resin composition

[0001] The present invention relates to a resin composition, a cured film obtained from the composition, and an electronic device equipped with the cured film.

[0002] In recent years, resin compositions employing polymer materials with excellent transparency in the visible light range have been widely used in the fields of electronic devices such as liquid crystal displays, organic EL displays, light-emitting diodes, solar cells, and CCD / CMOS image sensors for optical components such as protective films, planarization films, insulating films, anti-reflective films, refractive index control films, microlenses, intralayer lenses, optical waveguides, and film substrates. Such optical components require not only transparency but also excellent heat resistance and light resistance. Furthermore, these optical components often require a high refractive index to improve light extraction efficiency and light focusing.

[0003] Generally, methods for increasing the refractive index of polymer materials include introducing, for example, aromatic rings, halogen atoms other than fluorine atoms, sulfur atoms, metal atoms, or hydrogen bonds into the molecules of the polymer material. Regarding the introduction of aromatic rings, the introduction of fused cyclic hydrocarbon groups such as naphthalene rings and anthracene rings is a more effective means of increasing the refractive index of polymer materials than the introduction of monocyclic hydrocarbon groups such as phenyl groups (Patent Documents 1 and 2).

[0004] For example, a thermosetting resin composition has been proposed that can form a cured film having a high refractive index, as well as excellent transparency, heat resistance, light resistance, solvent resistance, flatness, and a dry etching rate equivalent to that of a resist (see Patent Document 3).

[0005] Japanese Patent Publication No. Hei 8-53517, International Publication No. 2008 / 143095, International Publication No. 2020 / 105458

[0006] Polymers contained in resin compositions used in the manufacture of optical components for electronic devices are preferably solvent-soluble, which is desirable for wastewater treatment in electronic device manufacturing. On the other hand, the cured film obtained from the resin composition is required to have good heat resistance and solvent resistance.

[0007] In view of the above circumstances, the object of the present invention is to provide a resin composition, a cured film obtained from the composition, and an electronic device equipped with the cured film, which has good solvent solubility of the contained polymer and can form a cured film that has good heat resistance and solvent resistance while having a high refractive index.

[0008] The inventors of the present invention conducted diligent research to solve the aforementioned problems and, as a result, found that they could solve the aforementioned problems, and completed the present invention having the following gist. That is, the present invention encompasses the following.

[0009] [1] A resin composition comprising the following components (A-1) and (C), or comprising the following components (A-2), (B), and (C). (A-1) component: A polymer having structural units represented by the following formula (1), the following formula (2), and the following formula (3). (A-2) component: A polymer having structural units represented by the following formula (1) and the following formula (3) (excluding the aforementioned component (A-1)). (B) component: A polymer having structural units represented by the following formula (2) (excluding the aforementioned component (A-1)). (C) component: An organic solvent. [In equations (1) and (2), R ０ represents a hydrogen atom or a methyl group, Ar represents an aromatic group having at least two benzene rings and possibly containing a heteroatom, and R １ R represents a single bond or an alkylene group with 1 to 5 carbon atoms. ２ represents a blocked isocyanate group. ] [2] The resin composition according to [1], wherein the aromatic group is a naphthyl group, anthracenyl group, phenanthryl group, carbazole group, biphenylyl group, or pyrenyl group. [3] The resin composition according to [1] or [2], wherein the structural unit represented by formula (2) is a structural unit represented by the following formula (2-1) or a structural unit represented by the following formula (2-2). [In equations (2-1) and (2-2), R ０ R is in equation (2) ０ This is synonymous with the definition of R １ R is in equation (2) １is synonymous with the definition. ] [4] The resin composition according to any one of [1] to [3], further comprising at least one component selected from the group consisting of the following (D) component, the following (E) component, the following (F) component, and the following (G) component. (D) component: A crosslinking agent having at least two polymerizable groups in one molecule. (E) component: An ultraviolet absorber. (F) component: A surfactant. (G) component: An antioxidant. [5] The resin composition according to any one of [1] to [4], wherein the weight average molecular weights of the polymer of the (A-1) component and the polymer of the (A-2) component are 3,000 to 50,000. [6] The resin composition according to any one of [1] to [5], which is a non-photosensitive resin composition. [7] A cured film obtained from the resin composition according to any one of [1] to [6]. [8] The cured film according to [7], having a glass transition temperature of 165 ° C or higher. [9] An electronic device provided with the cured film according to [7] or [8].

[0010] According to the present invention, a resin composition capable of forming a cured film having good solvent solubility of the contained polymer, high refractive index, and good heat resistance and solvent resistance, a cured film obtained from the composition, and an electronic device provided with the cured film can be obtained.

[0011] (Resin Composition) The resin composition of the present invention contains the following (A-1) component and the following (C) component. Alternatively, the resin composition of the present invention contains the following (A-2) component, the following (B) component, and the following (C) component. The resin composition may further contain other components.

[0012] (A-1) component: A polymer having a structural unit represented by the following formula (1), a structural unit represented by the following formula (2), and a structural unit represented by the following formula (3). (A-2) component: A polymer having a structural unit represented by the following formula (1) and a structural unit represented by the following formula (3) (excluding the (A-1) component). (B) component: A polymer having a structural unit represented by the following formula (i) (excluding the (A-1) component). (C) component: An organic solvent. [In formula (1) and formula (2), R ０ represents a hydrogen atom or a methyl group, Ar represents an aromatic group having at least two benzene rings and may contain heteroatoms, and R １R represents a single bond or an alkylene group with 1 to 5 carbon atoms. ２ This represents a blocked isocyanate group.

[0013] A resin composition can be obtained in which the polymer contained in the resin composition has structural units represented by formula (1), formula (2), and formula (3), thereby having good solvent solubility of the contained polymer and being able to form a cured film with good heat resistance and solvent resistance while having a high refractive index. The polymer may be a single copolymer or a blend of two or more polymers, as long as it has structural units represented by formula (1), formula (2), and formula (3). In the case of a blend of two or more polymers, these polymers may include homopolymers.

[0014] The resin composition of the present invention may contain component (A-1) and component (A-2), or component (A-1) and component (B), or component (A-1), component (A-2), and component (B).

[0015] <Components (A-1), (A-2), and (B)> Component (A-1): A polymer having structural units represented by the following formula (1), the following formula (2), and the following formula (3). Component (A-2): A polymer having structural units represented by the following formula (1) and the following formula (3) (excluding component (A-1)). Component (B): A polymer having structural units represented by the following formula (2) (excluding component (A-1)). [In equations (1) and (2), R ０ represents a hydrogen atom or a methyl group, Ar represents an aromatic group having at least two benzene rings and possibly containing a heteroatom, and R １ R represents a single bond or an alkylene group with 1 to 5 carbon atoms. ２ This represents a blocked isocyanate group.

[0016] <<Formula (1)>> In formula (1), Ar represents an aromatic group having at least two benzene rings and which may also contain heteroatoms. In the present invention, an aromatic fused ring has multiple aromatic monorings. That is, a naphthalene ring has two benzene rings. An anthracene ring has three benzene rings. A pyrene ring has four benzene rings.

[0017] Examples of aromatic groups include naphthyl, anthracenyl, phenanthryl, carbazole, biphenylyl, and pyrenyl groups.

[0018] The aromatic group in Ar may have substituents. Examples of substituents include C1-C6 alkyl groups, C1-C6 alkoxy groups, hydroxyl groups, and halogen atoms. Examples of halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. When the aromatic group has substituents, the number of substituents is not particularly limited, for example, 1 to 3.

[0019] Specific examples of compounds (monomers) that form the structural unit represented by formula (1) include 1-vinylnaphthalene, 2-vinylnaphthalene, 6-methyl-2-vinylnaphthalene, 5,8-dimethyl-2-vinylnaphthalene, 6-methoxy-2-vinylnaphthalene, 5,8-dimethoxy-2-vinylnaphthalene, 6-hydroxy-2-vinylnaphthalene, 5,8-dihydroxy-2-vinylnaphthalene, 6-bromo-2-vinylnaphthalene, 5,8-dibromo-2-vinylnaphthalene, 1-vinylanthracene, 2-vinylanthracene, 9-vinylanthracene, 9-vinylcarbazole, 4-vinylbiphenyl, 2-vinylfluorene, and 1-vinylpyrene. These compounds may be used individually or in combination of two or more.

[0020] <<Equation (2)>> R in Equation (2) １ This represents a single bond or an alkylene group having 1 to 5 carbon atoms. Examples of alkylene groups having 1 to 5 carbon atoms include the methylene group, 1,2-ethylene group, 1,3-propylene group, 1,4-butylene group, and 1,5-pentylene group.

[0021] R in equation (2) ２ This represents a blocked isocyanate group. A blocked isocyanate group is a group in which an isocyanate group (-N=C=O) is blocked by an appropriate protecting group. Examples of blocking agents for blocking isocyanate groups include alcohols such as methanol, ethanol, isopropanol, n-butanol, 2-ethoxyhexanol, 2-N,N-dimethylaminoethanol, 2-ethoxyethanol, and cyclohexanol; phenols such as phenol, o-nitrophenol, p-chlorophenol, o-cresol, m-cresol, and p-cresol; lactams such as ε-caprolactam; oximes such as acetone oxime, methyl ethyl ketone oxime, methyl isobutyl ketone oxime, cyclohexanone oxime, acetophenone oxime, and benzophenone oxime; pyrazoles such as pyrazole, 3,5-dimethylpyrazole, and 3-methylpyrazole; and thiols such as dodecanethiol and benzenethiol.

[0022] The structural unit represented by formula (2) is preferably the structural unit represented by formula (2-1) or formula (2-2) below. [In equations (2-1) and (2-2), R ０ R is in equation (2) ０ This is synonymous with the definition of R １ R is in equation (2) １ This is synonymous with the definition of [this].

[0023] Specific examples of compounds (monomers) that form the structural unit represented by formula (2) include, for example, 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate and 2-[O-(1'-methylpropyleneamino)carboxyamino]ethyl methacrylate.

[0024] The compounds (monomers) that form the structural unit represented by formula (2) may be commercially available products. Examples of commercially available products include Karenz® MOI-BP and MOI-BM (manufactured by Resonac Co., Ltd.).

[0025] The polymer that is component (A-1) may have structural units other than the structural units represented by formula (1), formula (2), and formula (3). The polymer that is component (A-2) (excluding component (A-1)) may have structural units other than the structural units represented by formula (1) and formula (3). The polymer that is component (B) (excluding component (A-1)) may have structural units other than the structural units represented by formula (2). The polymer that is component (B) may have structural units other than the structural units represented by formula (3), as long as it does not fall under component (A-1). Specific examples of compounds that form such "other structural units" (hereinafter sometimes referred to as "other monomers") include, for example, styrene, acenaphthylene, (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, isopropyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, benzyl (meth)acrylate, and γ-butyrolactone (meth)acrylate. Examples include ether, indene, N-methylmaleimide, N-ethylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N-benzylmaleimide, N-(4-hydroxyphenyl)maleimide, 2-hydroxyethyl vinyl ether, 3-hydroxypropyl vinyl ether, 4-hydroxybutyl vinyl ether, 5-hydroxypentyl vinyl ether, 6-hydroxyhexyl vinyl ether, 4-hydroxycyclohexyl vinyl ether, 1,4-cyclohexanedimethanol monovinyl ether, diethylene glycol monovinyl ether, and dipropylene glycol monovinyl ether.

[0026] The proportion of structural units represented by formula (1) in component (A-1) is not particularly limited, but from the viewpoint of obtaining a cured film with a higher refractive index, it is preferably 30 mol% or more, and more preferably 40 mol% or more, relative to the total structural units in component (A-1). The proportion of structural units represented by formula (1) in component (A-1) is preferably 80 mol% or less, and more preferably 70 mol% or less, relative to the total structural units in component (A-1). The proportion of structural units represented by formula (2) in component (A-1) is not particularly limited, but from the viewpoint of improving the solvent resistance of the cured film, it is preferably 3 mol% or more, and more preferably 5 mol% or more, relative to the total structural units in component (A-1). The proportion of structural units represented by formula (2) in component (A-1) is preferably 40 mol% or less, and more preferably 30 mol% or less, relative to the total structural units in component (A-1). The proportion of structural units represented by formula (3) in component (A-1) is not particularly limited, but from the viewpoint of improving the solvent solubility of component (A-1), it is preferably 5 mol% or more, and more preferably 10 mol% or more, relative to the total structural units in component (A-1). The proportion of structural units represented by formula (3) in component (A-1) is preferably 50 mol% or less, and more preferably 40 mol% or less, relative to the total structural units in component (A-1). The molar ratio of structural units represented by formula (2) to structural units represented by formula (3) in component (A-1) (structural units represented by formula (2):structural units represented by formula (3)) is not particularly limited, but it is preferably 1:5 to 3:1, and more preferably 1:4 to 2:1. The total proportion of structural units represented by formula (1), formula (2), and formula (3) in component (A-1) is not particularly limited, but is preferably 70 mol% to 100 mol%, more preferably 80 mol% to 100 mol%, and particularly preferably 90 mol% to 100 mol% relative to the total structural units in component (A-1).

[0027] The proportion of structural units represented by formula (1) in component (A-2) is not particularly limited, but from the viewpoint of obtaining a cured film with a higher refractive index, it is preferably 40 mol% or more, and more preferably 50 mol% or more, relative to the total structural units in component (A-2). The proportion of structural units represented by formula (1) in component (A-2) is preferably 90 mol% or less, and more preferably 80 mol% or less, relative to the total structural units in component (A-2). The proportion of structural units represented by formula (3) in component (A-2) is not particularly limited, but from the viewpoint of improving the solvent solubility of component (A-2), it is preferably 10 mol% or more, and more preferably 15 mol% or more, relative to the total structural units in component (A-2). The proportion of structural units represented by formula (3) in component (A-2) is preferably 50 mol% or less, and more preferably 40 mol% or less, relative to the total structural units in component (A-2). The total ratio of structural units represented by formula (1) and structural units represented by formula (3) in component (A-2) is not particularly limited, but is preferably 70 mol% to 100 mol%, more preferably 80 mol% to 100 mol%, and particularly preferably 90 mol% to 100 mol% relative to the total structural units in component (A-2).

[0028] The proportion of structural units represented by formula (2) in component (B) is not particularly limited, but is preferably 70 mol% to 100 mol%, more preferably 80 mol% to 100 mol%, and particularly preferably 90 mol% to 100 mol% relative to the total structural units in component (B).

[0029] The weight-average molecular weights of components (A-1), (A-2), and (B) are typically 1,000 to 100,000, preferably 3,000 to 50,000, and more preferably 6,000 to 40,000, respectively. The weight-average molecular weights are values ​​obtained using polystyrene as a standard sample by gel permeation chromatography (GPC).

[0030] When the resin composition contains the component (A-1), the content of the component (A-1) in the resin composition is not particularly limited, but is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 75% by mass or more based on the film constituent components of the resin composition. When the resin composition contains the component (A-2) and the component (B), the total content of the component (A-2) and the component (B) in the resin composition is not particularly limited, but is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 75% by mass or more based on the film constituent components of the resin composition. The film constituent components refer to the components other than the solvent (organic solvent) in the resin composition.

[0031] When the resin composition contains the component (A-2) and the component (B), the mass ratio of the component (A-2) to the component (B) [(A-2) component:(B) component] in the resin composition is not particularly limited, but is preferably 10:1 to 2:1, and more preferably 7:1 to 3:1.

[0032] The method for obtaining component (A-1) is not particularly limited. For example, component (A-1) can be obtained by polymerizing compounds (monomers) that form structural units represented by formulas (1), (2), and (3), and optionally other compounds (other monomers), in a solvent in the presence of a polymerization initiator at a temperature of usually 50°C to 120°C. The polymer obtained in this way is usually in a solution state dissolved in the solvent and can be used in the resin composition of the present invention without isolation in this state. Alternatively, the polymer solution obtained as described above can be added to a poor solvent such as stirred diethyl ether, toluene, methanol, ethanol, isopropanol, acetonitrile, or water to reprecipitate the polymer, the resulting precipitate can be decanted or filtered, and after washing as necessary, the polymer can be dried at room temperature or heated under atmospheric pressure or reduced pressure to obtain an oily substance or powder. Such operations can remove polymerization initiators and unreacted compounds coexisting with the polymer. In the present invention, the oily or powdery polymer may be used as is, or the oily or powdery polymer may be redissolved in a solvent, for example, as described later, and used in a solution. Examples of polymerization initiators include azo initiators and peroxide initiators. Examples of azo initiators include azobisisobutyronitrile and azobis(2,4-dimethylvaleronitrile). The method for obtaining component (A-2) and component (B) is the same as the method for obtaining component (A-1).

[0033] <(C) Component: Organic Solvent> The organic solvent contained in the resin composition is not particularly limited as long as it dissolves the polymer and other components contained in the resin composition. Examples of such organic solvents include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol mono Examples include butyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, 2-heptanone, γ-butyrolactone, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-ethyl-2-pyrrolidone. These organic solvents may be used individually or in combination of two or more.

[0034] Among these organic solvents, from the viewpoint of improving the leveling property of the coating film formed by applying the resin composition onto a substrate, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether, propylene glycol monopropyl ether, 2-heptanone, ethyl lactate, butyl lactate, methyl pyruvate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, cyclopentanone, cyclohexanone, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and γ-butyrolactone are preferred.

[0035] The content of the organic solvent in the resin composition is not particularly limited, but is preferably 20% by mass to 90% by mass, more preferably 40% by mass to 85% by mass, and particularly preferably 60% by mass to 80% by mass.

[0036] <Other Components> The resin composition may further contain at least one component selected from the group consisting of, for example, the following component (D), the following component (E), the following component (F), and the following component (G) as other components. Component (D): A crosslinking agent having at least two polymerizable groups in one molecule. Component (E): An ultraviolet absorber. Component (F): A surfactant. Component (G): An antioxidant.

[0037] <<Component (D): A Crosslinking Agent Having at Least Two Polymerizable Groups in One Molecule>> The resin composition can also contain a crosslinking agent having at least two polymerizable groups in one molecule (hereinafter sometimes referred to as "crosslinking agent"). The crosslinking agent is a compound that forms a bond with a polymer or a bond between crosslinking agents by the action of heat or an acid. Examples of the crosslinking agent include polyfunctional (meth)acrylate compounds, epoxy compounds, hydroxymethyl group-substituted phenol compounds, and compounds having an alkoxyalkylated amino group. These crosslinking agents can be used alone or in combination of two or more.

[0038] Examples of polyfunctional (meth)acrylate compounds include trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, glycerin tri(meth)acrylate, tris(2-hydroxyethyl) isocyanurate tri(meth)acrylate, Examples include ethylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and bis(2-hydroxyethyl) isocyanurate di(meth)acrylate.

[0039] As an epoxy compound, for example, a compound represented by the following general formula (10) can be used. (In the formula, k is an integer from 2 to 10, m is an integer from 0 to 4, and R3 represents a k-valent organic group.)

[0040] Specific examples of compounds having a cyclohexene oxide structure where m is 2 in the compound represented by formula (10) above include the compounds represented by formulas (11) and (12) below, as well as the commercially available products listed below, but are not limited to these examples. Examples of commercially available products include Epolide® GT-401, GT-403, GT-301, GT-302, Celoxide® 2021, and 3000 (all manufactured by Daicel Corporation).

[0041] Furthermore, as epoxy compounds, compounds represented by the following general formula (13) can also be used. (In the formula, k represents an integer from 2 to 10, and R4 represents a k-valent organic group.) Specific examples of compounds having the oxirane structure represented by the above formula (13) include, but are not limited to, the following commercially available products. Examples of epoxy resins having an aliphatic ring include Denacol® EX-252 (manufactured by Nagase Chemtex Co., Ltd.), EPICLON® 200, 400 (both manufactured by DIC Corporation), and jER® 871, 872 (both manufactured by Mitsubishi Chemical Corporation). Examples of bisphenol A type epoxy resins include jER® 828, 834, 1001, 1004 (all manufactured by Mitsubishi Chemical Corporation), and EPICLON® 850, 860, 4055 (all manufactured by DIC Corporation). Examples of bisphenol F type epoxy resins include jER® 807 (manufactured by Mitsubishi Chemical Corporation) and EPICLON® 830 (manufactured by DIC Corporation). Examples of phenol novolac type epoxy resins include EPICLON® N-740, N-770, N-775 (all manufactured by DIC Corporation), jER® 152, and 154 (all manufactured by Mitsubishi Chemical Corporation). Examples of cresol novolac type epoxy resins include EPICLON® N-660, N-665, N-670, N-673, N-680, N-695, N-665-EXP, and N-672-EXP (all manufactured by DIC Corporation). Examples of glycidylamine-type epoxy resins include EPICLON® 430 and 430-L (both manufactured by DIC Corporation), TETRAD®-C and TETRAD®-X (both manufactured by Mitsubishi Gas Chemical Company, Inc.), jER® 604 and 630 (both manufactured by Mitsubishi Chemical Corporation), SumiEpoxy® ELM120, ELM100, ELM434, and ELM434HV (all manufactured by Sumitomo Chemical Co., Ltd.), and Epotote® YH-434 and YH-434L (both manufactured by Nippon Steel Chemical & Material Co., Ltd.).

[0042] Of these, the compounds represented by formulas (11) and (12), Epolid® GT-401, GT-403, GT-301, GT-302, Celoxide® 2021, and 3000, which have a cyclohexene oxide structure, are preferred as component (D) from the viewpoint of heat resistance, solvent resistance, process resistance such as resistance to long-term firing, and transparency.

[0043] Examples of hydroxymethyl group-substituted phenol compounds include 2-hydroxymethyl-4,6-dimethylphenol, 1,3,5-trihydroxymethylbenzene, and 3,5-dihydroxymethyl-4-methoxytoluene [2,6-bis(hydroxymethyl)-p-cresol].

[0044] Examples of compounds having alkoxyalkylated amino groups include nitrogen-containing compounds having multiple active methylol groups in a single molecule, such as (poly)methylolated melamine, (poly)methylolated glycoluryl, (poly)methylolated benzoguanamine, and (poly)methylolated urea, in which at least one hydrogen atom of the hydroxyl group of the methylol group is substituted with an alkyl group such as a methyl group or a butyl group.

[0045] Compounds having alkoxyalkylated amino groups may be mixtures of multiple substituted compounds, and mixtures containing oligomeric components formed by partial self-condensation also exist; such mixtures can also be used. More specifically, examples include products in the CYMEL series such as hexamethoxymethylmelamine (manufactured by Ornex Co., Ltd., CYMEL® 303), tetrabutoxymethylglycoluryl (manufactured by Ornex Co., Ltd., CYMEL® 1170), and tetramethoxymethylbenzoguanamine (manufactured by Ornex Co., Ltd., CYMEL® 1123); products in the Nikalac series such as methylated melamine resin (manufactured by Sanwa Chemical Co., Ltd., Nikalac® MW-30HM, MW-390, MW-100LM, MX-750LM); and methylated urea resin (manufactured by Sanwa Chemical Co., Ltd., Nikalac® MX-270, MX-280, MX-290).

[0046] The content of component (D) in the resin composition is preferably 5% to 30% by mass relative to component (A-1). The content of component (D) in the resin composition is preferably 5% to 30% by mass relative to the sum of components (A-2) and (B).

[0047] <<(E) Component: UV absorber>> The resin composition may also contain a UV absorber for the purpose of improving light resistance. Examples of UV absorbers include triazine-based UV absorbers, benzotriazole-based UV absorbers, benzophenone-based UV absorbers, cyclic iminoester-based UV absorbers, cyanoacrylate-based UV absorbers, malonic acid-based UV absorbers, and phenyl salicylate-based UV absorbers. Among these, triazine-based UV absorbers are preferred.

[0048] Triazine-based ultraviolet absorbers are, for example, compounds comprising a triazine ring and three optionally substituted phenyl groups bonded to the carbon atoms of the triazine ring, wherein at least one of the three phenyl groups is represented by the following formula (4). (In the formula, * represents the bond between the triazine ring and the carbon atom, A ３ and A ４ Each of these independently represents a hydrogen atom or an organic group.

[0049] Examples of triazine-based ultraviolet absorbers include compounds represented by the following formulas (T-1) to (T-15).

[0050] Examples of commercially available triazine-based UV absorbers include Tinuvin® 400, 405, 460, 477, 479, 1577ED, and 1600 (all manufactured by BASF Japan Ltd.), Adeka Stab® LA-46 and LA-F70 (both manufactured by ADEKA Corporation), and KEMISORB® 102 (manufactured by Chemipro Chemical Co., Ltd.). These triazine-based UV absorbers may be used individually or in combination of two or more.

[0051] The amount of ultraviolet absorber contained in the resin composition is preferably 3% to 20% by mass, more preferably 5% to 20% by mass, relative to component (A-1). The amount of ultraviolet absorber contained in the resin composition is preferably 3% to 20% by mass, more preferably 5% to 20% by mass, relative to the sum of components (A-2) and (B).

[0052] <<(F) Component: Surfactant>> The resin composition may also contain a surfactant for the purpose of improving its applicability. Examples of the surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, and polyoxyethylene oleyl ether; polyoxyethylene alkylaryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; polyoxyethylene / polyoxypropylene block copolymers; sorbitan fatty acid esters such as sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan monooleate, sorbitan trioleate, and sorbitan tristearate; and polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan trioleate, and polyoxyethylene sorbitan tristearate. Nonionic surfactants such as rubitan fatty acid esters, F-Top® EF301, EF303, EF352 (all manufactured by Mitsubishi Materials Electronic Chemicals Co., Ltd.), Megafac® F171, F173, R-30, R-40, R-40-LM (all manufactured by DIC Corporation), Florard FC430, FC431 (all manufactured by Sumitomo 3M Limited), Asahiguard® AG710, Surflon® S-382, SC101, SC1 Fluorine-based surfactants such as 02, SC103, SC104, SC105, SC106 (all manufactured by AGC Inc.), DFX-18, FTX-206D, FTX-212D, FTX-218, FTX-220D, FTX-230D, FTX-240D, FTX-212P, FTX-220P, FTX-228P, FTX-240G, etc., Futergent series (all manufactured by Neos Co., Ltd.), organosiloxane polymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow No. 7, No. 36, No. 50E, No. 75, No. 77, No. 85, No. 85HF, No. 90, same No. 90D-50, same No. 95, same No. 99C, PW-95 (above,Examples include non-fluorinated surfactants such as BYK-302, BYK-307, BYK-322, BYK-323, BYK-330, BYK-333, BYK-350, BYK-354, BYK-370, BYK-375, BYK-378, and BYK-399 (all manufactured by BYK-Chemie Co., Ltd.). These surfactants can be used individually or in combination of two or more.

[0053] Furthermore, when the surfactant is used, its content in the resin composition is usually 0.0001% to 3% by mass, preferably 0.001% to 1% by mass, and more preferably 0.01% to 0.5% by mass, based on the solid content of the resin composition.

[0054] <<(G) Component: Antioxidant>> The resin composition may also contain an antioxidant. Examples of antioxidants include phenolic antioxidants and sulfide antioxidants.

[0055] Examples of phenolic antioxidants include IRGANOX® 245, 1010, 1035, 1076, and 1135 (all manufactured by BASF Japan Ltd.), SUMILIZER® GA-80, GP, MDP-S, BBM-S, and WX-R (all manufactured by Sumitomo Chemical Co., Ltd.), and ADEKA STAB® AO-20, AO-30, AO-40, AO-50, AO-60, AO-80, and AO-330 (all manufactured by ADEKA Corporation). Examples of sulfide-based antioxidants include ADEKA STAB® AO-412S and AO-503 (both manufactured by ADEKA Corporation), IRGANOX® PS802 and PS800 (both manufactured by BASF Japan Ltd.), and SUMILIZER® TP-D (manufactured by Sumitomo Chemical Co., Ltd.).

[0056] When an antioxidant is used, its content in the resin composition is usually 0.0001% to 3% by mass, preferably 0.001% to 1% by mass, and more preferably 0.01% to 0.5% by mass, based on the solid content of the resin composition.

[0057] The resin composition is, for example, a non-photosensitive resin composition. The resin composition does not contain a photosensitive agent. An example of a photosensitive agent is a 1,2-naphthoquinone diazide compound. An example of a 1,2-naphthoquinone diazide compound is a compound having hydroxyl groups, wherein 10 to 100 mol% (for example, 20 to 95 mol%) of these hydroxyl groups are esterified with 1,2-naphthoquinone diazide sulfonic acid.

[0058] (Cured Film) The cured film of the present invention is obtained from the resin composition of the present invention. An example of a method for producing the cured film will be described. The resin composition of the present invention is applied to a substrate (for example, PET film, TAC film, semiconductor substrate, glass substrate, quartz substrate, silicon wafer, and substrates on which various metal films or color filters are formed) using an appropriate coating method such as a spinner or coater, and then baked using a heating means such as a hot plate or oven to produce a cured film. The baking conditions are appropriately selected from a baking temperature of 50°C to 300°C and a baking time of 0.1 to 360 minutes. The baking process for producing the cured film may be carried out in two or more steps.

[0059] The thickness of the cured film is, for example, 0.001 μm to 1000 μm, preferably 0.01 μm to 100 μm, and more preferably 0.1 μm to 10 μm.

[0060] The glass transition temperature of the cured film is not particularly limited, but from the viewpoint of the heat resistance of the cured film, it is preferably 165°C or higher, and more preferably 180°C or higher. The upper limit of the glass transition temperature of the cured film is not particularly limited, but for example, it may be 250°C or lower, or 220°C or lower.

[0061] In this invention, the glass transition temperature of the cured film can be determined by the following method. The resin composition is diluted with a solvent (e.g., propylene glycol monomethyl ether acetate) as needed, and then coated onto a silicon wafer using a spin coater. The film is baked on a hot plate at 100°C for 1 minute, and then at 230°C for 10 minutes to form a film with a thickness of 1000 nm. The silicon wafer on which the film has been formed is processed into a 1 cm × 2 cm test piece. The test piece is annealed by heating it from 40°C to 110°C at a heating rate of 10°C / min under a nitrogen atmosphere. Then, the test piece is placed on a hot plate adjusted to heat at a rate of 10°C / min and heated from 40°C to 260°C. The film thickness at each temperature is measured using an optical interferometry film thickness analyzer manufactured by Filmetrics. A film thickness-temperature change curve is created from the obtained data, and the glass transition temperature is calculated from the change in film thickness. Note that annealing is a process to flatten the thermal history. Furthermore, using the obtained data, in a film thickness-temperature change curve with temperature on the x-axis and film thickness on the y-axis, the temperature at the intersection of the regression line obtained from data before the change in film thickness becomes large and the regression line obtained from data after the change in film thickness becomes large is defined as the glass transition temperature. The regression line is determined by the least squares method.

[0062] (Electronic Devices) The electronic devices of the present invention include the cured film of the present invention. Examples of electronic devices include liquid crystal displays, organic EL displays, light-emitting diodes, solar cells, and CCD / CMOS image sensors. In electronic devices, the cured film of the present invention is used, for example, as a protective film, planarization film, insulating film, anti-reflective film, refractive index control film, microlens, intralayer lens, optical waveguide, and film substrate.

[0063] The present invention will be described in more detail below with reference to synthesis examples, examples, and comparative examples, but the present invention is not limited to the following examples.

[0064] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) of the polymers obtained in the synthesis example below were measured under the following conditions: Apparatus: GPC system manufactured by JASCO Corporation Column: Shodex® KL-804L and 803L Column oven: 40°C Flow rate: 1 ml / min Eluent: Tetrahydrofuran

[0065] The compounds used in the following synthesis examples, examples, and comparative examples are as follows: [Solvents] PGMEA: Propylene glycol monomethyl ether acetate PGME: Propylene glycol monomethyl ether EL: Ethyl lactate MEK: Methyl ethyl ketone

[0066] [Raw material monomers] VN: 2-vinylnaphthalene VBP: 4-vinylbiphenyl VC: 9-vinylcarbazole MOIBP: 2-[(3,5-dimethylpyrazolyl)carbonylamino]ethyl methacrylate (Resonac Co., Ltd., product name: Karenz (registered trademark) MOI-BP) MI: maleimide GMA: glycidyl methacrylate BEMA: 1-(butoxy)ethyl methacrylate HEMA: 2-hydroxyethyl methacrylate

[0067] [1] Synthesis of Polymers <Synthesis Example 1> 7.00 g (45.39 mmol) of VN, 1.75 g (6.98 mmol) of MOIBP, 1.69 g (17.46 mmol) of MI, and 0.80 g of azobisisobutyronitrile as a polymerization catalyst were dissolved in 16.8 g of PGMEA and reacted at 70°C for 20 hours to obtain a polymer solution with a solid content of 40% by mass. The obtained polymer solution was gradually added dropwise to 500 g of methanol to precipitate the solid. The precipitated solid was filtered off and dried under reduced pressure to obtain a polymer (A-1) having repeating units represented by the following formula. The obtained polymer had a Mw of 20,300 and a Mn of 7,400.

[0068]

[0069] <Synthesis Examples 2-3> Polymers (A-2) and (A-3) were obtained in the same manner as in Synthesis Example 1, except that the charging ratio of the raw material monomers was changed to the charging ratio shown in Table 1.

[0070] <Synthesis Example 4> 5.00 g (27.74 mmol) of VBP, 2.32 g (9.25 mmol) of MOIBP, 0.90 g (9.25 mmol) of MI, and 0.53 g of azobisisobutyronitrile as a polymerization catalyst were dissolved in 49.6 g of PGMEA and reacted at 70°C for 20 hours to obtain a polymer solution with a solid content of 15% by mass. The obtained polymer solution was gradually added dropwise to 500 g of methanol to precipitate the solid. The precipitated solid was filtered off and dried under reduced pressure to obtain a polymer (A-4) having repeating units represented by the following formula. The obtained polymer had a Mw of 15,200 and a Mn of 6,000.

[0071]

[0072] <Synthesis Example 5> VC 4.50 g (23.29 mmol), MOIBP 4.68 g (18.63 mmol), MI 0.45 g (4.66 mmol), and azobisisobutyronitrile 0.68 g as a polymerization catalyst were dissolved in 58.5 g of PGMEA and reacted at 85°C for 20 hours to obtain a polymer solution with a solid content of 15% by mass. The obtained polymer solution was gradually added dropwise to 500 g of methanol to precipitate the solid. The precipitated solid was filtered off and dried under reduced pressure to obtain a polymer (A-5) having repeating units represented by the following formula. The obtained polymer had a Mw of 7,500 and a Mn of 3,200.

[0073]

[0074] <Synthesis Example 6> 7.00 g (45.39 mmol) of VN, 1.47 g (15.13 mmol) of MI, and 0.70 g of azobisisobutyronitrile as a polymerization catalyst were dissolved in 13.7 g of PGMEA and reacted at 70°C for 20 hours to obtain a polymer solution with a solid content of 40% by mass. The obtained polymer solution was gradually added dropwise to 500 g of methanol to precipitate the solid. The precipitated solid was filtered off and dried under reduced pressure to obtain a polymer (A-6) having repeating units represented by the following formula. The obtained polymer had a Mw of 16,000 and a Mn of 6,200.

[0075]

[0076] <Synthesis Example 7> 10.00 g (39.79 mmol) of MOIBP and 0.78 g of azobisisobutyronitrile as a polymerization catalyst were dissolved in 25.1 g of PGMEA and reacted at 70°C for 20 hours to obtain a polymer solution with a solid content of 30% by mass. The obtained polymer solution was gradually added dropwise to 500 g of methanol to precipitate the solid. The precipitated solid was filtered off and dried under reduced pressure to obtain a polymer (A-7) having repeating units represented by the following formula. The obtained polymer had a Mw of 32,000 and a Mn of 14,000.

[0077]

[0078] <Comparative Synthesis Example 1> 7.00 g (45.39 mmol) of VN, 0.81 g (5.67 mmol) of GMA, 1.05 g (5.67 mmol) of BEMA, and 0.28 g of azobisisobutyronitrile as a polymerization catalyst were dissolved in 13.8 g of PGMEA and reacted at 70°C for 20 hours to obtain a polymer (A-8) solution with a solid content of 40% by mass and having repeating units represented by the following formula. The obtained polymer had a Mw of 16,100 and a Mn of 6,000.

[0079]

[0080] <Comparative Synthesis Example 2> 7.00 g (45.39 mmol) of VN, 1.43 g (5.67 mmol) of MOIBP, 0.74 g (5.67 mmol) of HEMA, and 0.28 g of azobisisobutyronitrile as a polymerization catalyst were dissolved in 14.1 g of PGMEA and reacted at 70°C for 20 hours to obtain a polymer solution with a solid content of 40% by mass. The obtained polymer solution was gradually added dropwise to 500 g of methanol to precipitate the solid. The precipitated solid was filtered off and dried under reduced pressure to obtain a polymer (A-9) having repeating units represented by the following formula. The obtained polymer had a Mw of 20,300 and a Mn of 10,300.

[0081]

[0082] Table 1 summarizes the raw material monomer composition ratios (mol ratio), Mw, and Mn for Synthesis Examples 1-7 and Comparative Examples 1-2.

[0083]

[0084] [2] Preparation of resin composition [Example 1-1] 100 parts by mass of the polymer (A-1) obtained in Synthesis Example 1 was mixed with 5 parts by mass of Tinuvin 479 (manufactured by BASF Japan Ltd.) as an ultraviolet absorber and 0.03 parts by mass of R-30 (manufactured by DIC Corporation) as a surfactant. PGMEA was added as an organic solvent to obtain a solution with a solid content of 27.0% by mass. The obtained solution was then filtered using a PTFE microfilter with a pore size of 0.2 μm to prepare resin composition (B-1).

[0085] [Examples 1-2 to 1-5, Comparative Examples 1-1 to 1-2] Resin compositions (B-2) to (B-5) and (B-7) to (B-8) were prepared using the same formulation and method as in Example 1-1, except that polymers (A-2) to (A-5) and (A-7) to (A-8) were used instead of polymer (A-1).

[0086] [Examples 1-6] 100 parts by mass of the polymer (A-6) obtained in Synthesis Example 6 (based on solid content), 20 parts by mass of the polymer (A-7) obtained in Synthesis Example 7 (based on solid content), 5 parts by mass of Tinuvin 479 (manufactured by BASF Japan Ltd.) as an ultraviolet absorber, and 0.03 parts by mass of R-30 (manufactured by DIC Corporation) as a surfactant were mixed together, and PGMEA was added as an organic solvent to obtain a solution with a solid content concentration of 27.0% by mass. The obtained solution was then filtered using a PTFE microfilter with a pore size of 0.2 μm to prepare resin composition (B-6).

[0087] [3] Evaluation of Resin Compositions and Films [Solubility] 0.2 g of each resin composition prepared in Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-2 was added dropwise to 1.8 g of each organic solvent (PGME, PGMEA, EL, MEK) shown in Table 2, and the presence or absence of precipitation was visually observed. Solubility was evaluated according to the following criteria. The results are shown in Table 2. <<Evaluation Criteria>> ○: No precipitation occurred ×: Precipitation occurred

[0088] [Solvent Resistance] The resin compositions prepared in Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-2 were each coated onto a silicon wafer using a spin coater, and baked on a hot plate at 100°C for 1 minute, followed by 230°C for 10 minutes, to form a film with a thickness of 3000 nm. The obtained film was immersed in acetone for 10 minutes, dried on a hot plate at 100°C for 30 seconds, and then the film thickness was measured. The residual film percentage was calculated from the film thickness before and after immersion using the following formula. The residual film percentage was then evaluated according to the following criteria. The results are shown in Table 2. Residual film percentage (%) = [[Film thickness after immersion] / [Film thickness before immersion]] × 100 <<Evaluation Criteria>> ○: Residual film percentage of 90% or more ×: Residual film percentage of less than 90%

[0089] [Refractive Index] The resin compositions prepared in Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-2 were each diluted to a predetermined concentration with PGMEA and then coated onto a silicon wafer using a spin coater. The mixtures were baked on a hot plate at 100°C for 1 minute, followed by baking at 230°C for 10 minutes to form a film with a thickness of 1000 nm. The refractive index of these films at a wavelength of 550 nm was measured using a spectroscopic ellipsometer M-2000 (manufactured by J.A. Woolam Japan Co., Ltd.). The results are shown in Table 2.

[0090] [Glass Transition Temperature] The resin compositions prepared in Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-2 were each diluted to a predetermined concentration with PGMEA and then coated onto a silicon wafer using a spin coater. A film with a thickness of 1000 nm was formed by baking on a hot plate at 100°C for 1 minute, followed by 230°C for 10 minutes. The silicon wafers with the formed films were processed into 1 cm × 2 cm test pieces. The test pieces were annealed by heating them in a nitrogen atmosphere from 40°C to 110°C at a heating rate of 10°C / min. After that, the test pieces were placed on a hot plate adjusted to a heating rate of 10°C / min and heated from 40°C to 260°C. The film thickness at each temperature was measured using an optical interferometry film thickness analyzer manufactured by Filmetrics. A film thickness-temperature change curve was created from the obtained data, and the glass transition temperature was calculated from the change in film thickness. The results are shown in Table 2. Furthermore, using the obtained data, the temperature at the intersection of the regression line obtained from data before the change in film thickness became large and the regression line obtained from data after the change in film thickness became large in the film thickness-temperature change curve (with temperature on the x-axis and film thickness on the y-axis) was defined as the glass transition temperature. The regression lines were determined by the least squares method.

[0091] Table 2 summarizes the types of polymers contained in each resin composition and the evaluation results. In Table 2, Tg represents the glass transition temperature.

[0092]

[0093] The resin compositions of Examples 1-1 to 1-6 did not precipitate when mixed with the organic solvents shown in Table 2, demonstrating excellent solubility in those organic solvents. On the other hand, the resin composition of Comparative Example 1-1 precipitated when mixed with a specific organic solvent, resulting in low solubility in that particular organic solvent.

[0094] The films formed from the resin compositions of Examples 1-1 to 1-6 all exhibited high refractive indices and glass transition temperatures of 165°C or higher, demonstrating high heat resistance. On the other hand, the resin compositions of Comparative Examples 1-1 and 1-2 had glass transition temperatures of 153°C or lower, resulting in low heat resistance.

[0095] These experimental findings suggest that the crosslinking mechanism consisting of blocked isocyanate groups and maleimide groups exhibits excellent properties in both solubility and heat resistance after film formation.

Claims

1. A resin composition comprising the following components (A-1) and (C), or comprising the following components (A-2), (B), and (C). (A-1) component: A polymer having structural units represented by the following formula (1), the following formula (2), and the following formula (3). (A-2) component: A polymer having structural units represented by the following formula (1) and the following formula (3) (excluding the aforementioned component (A-1)). (B) component: A polymer having structural units represented by the following formula (2) (excluding the aforementioned component (A-1)). (C) component: An organic solvent. [In equations (1) and (2), R ０ represents a hydrogen atom or a methyl group, Ar represents an aromatic group having at least two benzene rings and possibly containing a heteroatom, and R １ R represents a single bond or an alkylene group with 1 to 5 carbon atoms. ２ This represents a blocked isocyanate group.

2. The resin composition according to claim 1, wherein the aromatic group is a naphthyl group, anthracenyl group, phenanthryl group, carbazole group, biphenylyl group, or pyrenyl group.

3. The resin composition according to claim 1 or claim 2, wherein the structural unit represented by formula (2) is the structural unit represented by the following formula (2-1) or the structural unit represented by the following formula (2-2). [In equations (2-1) and (2-2), R ０ R is in equation (2) ０ This is synonymous with the definition of R １ R is in equation (2) １ This is synonymous with the definition of [this].

4. The resin composition according to claim 1 or claim 2, further comprising at least one component selected from the group consisting of component (D), component (E), component (F), and component (G) below. (D): A crosslinking agent having at least two polymerizable groups in one molecule. (E): A UV absorber. (F): A surfactant. (G): An antioxidant.

5. The resin composition according to claim 1 or claim 2, wherein the weight-average molecular weight of the polymer of component (A-1) and the polymer of component (A-2) is 3,000 to 50,000.

6. The resin composition according to claim 1 or claim 2, which is a non-photosensitive resin composition.

7. A cured film obtained from the resin composition according to claim 1 or claim 2.

8. The cured film according to claim 7, wherein the glass transition temperature is 165°C or higher.

9. An electronic device comprising the cured film described in claim 7.

Images