Curable composition, cured product, polymer, and polymer for resist

Abstract

The purpose of the present invention is to provide a curable composition which can be developed with an environmentally friendly developer solution. A curable composition according to the present invention is characterized by containing a polymer (A) that comprises a repeating structural unit (a1) having a polyoxyalkylene structure and / or a monomer (B) having a polyoxyalkylene structure.

Description

Curable compositions, cured products, polymers, and resist polymers

[0001] The present invention relates to a curable composition, a cured product, a polymer, and a resist polymer.

[0002] Photosensitive resin compositions are widely used for forming circuit patterns in large-scale integrated circuits (LSIs), for forming photospacers in liquid crystal displays (LCDs), for forming color filter partition walls and for forming ITO (indium tin oxide) electrode partition walls, and for forming overcoat films, planarizing films and protective films in organic light-emitting diode (OLED) elements.

[0003] For example, Patent Document 1 proposes a photosensitive resin composition comprising: (A) a first copolymer including (a1) structural units derived from an ethylenically unsaturated carboxylic acid, an ethylenically unsaturated carboxylic acid anhydride, or a combination thereof; (a2) structural units derived from an ethylenically unsaturated compound containing an alicyclic epoxy group; (a3) ​​structural units derived from an ethylenically unsaturated compound containing an acyclic epoxy group; and (a4) structural units derived from an ethylenically unsaturated compound different from (a1) to (a3); (B) a second copolymer including a specific repeating unit having a carboxy group; (C) a photopolymerizable compound; (D) a photopolymerization initiator; and (E) a solvent.

[0004] JP 2022-81464 A

[0005] However, conventional photosensitive resin compositions require development using organic solvents or strongly alkaline developers that have a high environmental impact, which has disadvantages in terms of the environment, ease of handling, waste liquid treatment costs, etc.

[0006] The present invention has been made in view of the above-mentioned problems, and aims to provide a curable composition that can be developed with (1) a developer that uses an organic solvent that has a low environmental impact, (2) a developer that does not contain a material that has a high environmental impact or is difficult to handle, or in which the content of such a material is reduced compared to conventional developers, and (3) a developer such as a neutral or weakly alkaline developer (hereinafter, these are collectively referred to as "environmentally friendly developers").

[0007] The present inventors have conducted extensive research to solve the above-mentioned problems and have found that the above-mentioned problems can be solved by using a polymer (A) containing a repeating structural unit (a1) having a polyoxyalkylene structure or a monomer (B) having a polyoxyalkylene structure. Based on this finding, the present invention has been completed through further research.

[0008] That is, the present invention provides the following aspects. <1> A curable composition containing a polymer (A) including a repeating structural unit (a1) having a polyoxyalkylene structure, and / or a monomer (B) having a polyoxyalkylene structure. <2> The curable composition according to <1>, in which the polymer (A) further includes a repeating structural unit (a2) having an alkoxysilyl group. <3> The curable composition according to <2>, in which the polymer (A) further includes a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group. <4> The curable composition according to any one of <1> to <3>, which is a resist material. <5> A cured product obtained from the curable composition according to any one of <1> to <4>. <6> The cured product according to <5>, which is a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an overcoat film, an optical waveguide, or a planarizing film. <7> A polymer comprising a repeating structural unit (a1) having a polyoxyalkylene structure, a repeating structural unit (a2) having an alkoxysilyl group, and a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group. <8> A resist polymer comprising a repeating structural unit (a1) having a polyoxyalkylene structure and a repeating structural unit (a2) having an alkoxysilyl group. <9> The resist polymer according to <8>, wherein the resist polymer further comprises a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group. <10> Use of a polymer comprising a repeating structural unit (a1) having a polyoxyalkylene structure and a repeating structural unit (a2) having an alkoxysilyl group for the production of a resist polymer. <11> Use of the polymer according to <10>, wherein the polymer further comprises a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group.

[0009] The curable composition of the present invention contains the polymer (A) including the repeating structural unit (a1) having a polyoxyalkylene structure and / or the monomer (B) having a polyoxyalkylene structure, and therefore has the advantage that it can be developed even with an environmentally friendly developer.

[0010] In the present invention, (meth)acrylate means acrylate and / or methacrylate, (meth)acrylic means acrylic and / or methacrylic, (meth)acryloyl means acryloyl and / or methacryloyl, and (meth)acrylic acid means acrylic acid and / or methacrylic acid.

[0011] 1. Curable Composition The curable composition of the present invention is characterized by containing a polymer (A) containing a repeating structural unit (a1) having a polyoxyalkylene structure, and / or a monomer (B) having a polyoxyalkylene structure. The curable composition of the present invention will be described in detail below.

[0012] [Polymer (A)] The polymer (A) contains at least a repeating structural unit (a1) having a polyoxyalkylene structure. The repeating structural unit (a1) having a polyoxyalkylene structure is contained in the polymer (A) in order to impart the property of being developable with a developer to the curable composition.

[0013] The developer capable of developing the curable composition of the present invention is not particularly limited, and conventionally used developers such as organic solvents or strong alkaline aqueous solutions (e.g., a 2.38% TMAH (tetramethylammonium hydroxide) aqueous solution, pH 13.3) may be used. However, from the viewpoints of environmental considerations and wastewater treatment costs, it is preferable to use an environmentally friendly developer. The pH of the environmentally friendly developer is preferably neutral (pH 6-8) or weakly alkaline (pH 8-11), more preferably pH 7-10, and even more preferably pH 7-9. The materials for the environmentally friendly developer are not particularly limited, but it is preferable to use an organic solvent or water that has a low environmental impact as the main component. Examples of organic solvents that have a relatively low environmental impact include alcohols such as methanol and ethanol. Specific examples of environmentally friendly developers include water, mixtures of water and the above alcohols, aqueous Na2CO3 solutions (typically pH 10 or less), and aqueous TMAH solutions with a concentration of 0.1% or less. By including the polymer (A), the curable composition of the present invention can obtain sufficient development performance even when using an environmentally friendly developer.

[0014] <Repeating structural unit (a1) having a polyoxyalkylene structure> The monomer (a1′) forming the repeating structural unit (a1) having a polyoxyalkylene structure is not particularly limited as long as it has a functional group containing an ethylenically unsaturated double bond (hereinafter also referred to as a “radical polymerizable functional group”) and a polyoxyalkylene structure.

[0015] The radically polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. From the viewpoint of polymerizability with monomers that form other structural units, a (meth)acryloyl group or a (meth)acryloyloxy group is preferred.

[0016] The polyoxyalkylene structure is not particularly limited as long as the curable composition containing the polymer (A) having the polyoxyalkylene structure can be developed with an environmentally friendly developer, and examples thereof include those containing at least one alkylene oxide having 2 to 6 carbon atoms, such as ethylene oxide, propylene oxide, and butylene oxide. When the polyoxyalkylene structure contains two or more alkylene oxides, the two or more alkylene oxides may be randomly added or block added. Specific examples of the polyoxyalkylene structure include a polyoxyethylene structure, a polyoxypropylene structure, a polyoxybutylene structure, a polyoxyethylene polyoxypropylene structure, a polyoxyethylene polyoxybutylene structure, a polyoxypropylene polyoxybutylene structure, and a polyoxyethylene polyoxypropylene polyoxybutylene structure. The polyoxyalkylene structure is preferably a polyoxyethylene structure or a polyoxypropylene structure, more preferably a polyoxyethylene structure, from the viewpoint of excellent developability when the curable composition is developed with an environmentally friendly developer.

[0017] The average number of moles of alkylene oxide added in the polyoxyalkylene structure is not particularly limited and is, for example, 2 to 100. From the viewpoint of improving the developability when the curable composition is developed with an environmentally friendly developer and from the viewpoint of improving the patterning properties (lithography properties) of the curable composition, it is preferably 4 to 80, more preferably 6 to 60, even more preferably 7 to 40, and still more preferably 8 to 30.

[0018] The atom or group at the end of the polyoxyalkylene structure (i.e., the atom or group at the end bonded to the oxygen atom) is not particularly limited, and examples thereof include a hydrogen atom, an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, and an aryl group, preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, and still more preferably an alkyl group having 1 to 4 carbon atoms. The alkyl group and alkenyl group may be linear or branched.

[0019] The radical polymerizable functional group and the polyoxyalkylene structure may be bonded directly or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched aliphatic saturated or aliphatic unsaturated hydrocarbon groups, alicyclic saturated or alicyclic unsaturated hydrocarbon groups (including bridged rings and fused rings), aromatic hydrocarbon groups, organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.), and organic groups in which two or more of these are bonded. In addition, the hydrocarbon group and the organic group may have various substituents (e.g., halogen groups, hydroxy groups, alkyl groups, alkenyl groups, alkoxy groups, aryl groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.).

[0020] The polymer (A) may contain one type of the polyoxyalkylene structure or two or more types thereof.

[0021] In the polymer (A), the content of the repeating structural unit (a1) having a polyoxyalkylene structure is not particularly limited and is, for example, 5 to 100 mol %, and from the viewpoint of improving the developability when the curable composition is developed with an environmentally friendly developer and improving the patterning properties (lithography properties) of the curable composition, the content is preferably 10 to 90 mol %, more preferably 15 to 70 mol %, even more preferably 20 to 60 mol %, and particularly preferably 20 to 50 mol %.

[0022] <Repeating structural unit (a2) having an alkoxysilyl group> The polymer (A) preferably further contains a repeating structural unit (a2) having an alkoxysilyl group. When the polymer (A) contains the repeating structural unit (a2) having an alkoxysilyl group, it is possible to form a cured product having excellent solvent resistance even when cured at low temperatures (for example, 100 ° C or less), and it is also possible to improve the patterning properties (lithography properties) of the curable composition. The reason why the polymer (A) contains the repeating structural unit (a2) having an alkoxysilyl group is able to achieve the above-mentioned effect is not limited by theory, but is thought to be because, when the curable composition is cured, even at low temperatures, siloxane bonds are formed by hydrolysis and dehydration condensation of the alkoxysilyl group, causing crosslinking between polymers (A), or a crosslinked structure is formed by the reaction of the alkoxysilyl group of the polymer (A) with a compound having a hydroxyl group, etc.

[0023] The monomer (a2') that forms the repeating structural unit (a2) having an alkoxysilyl group is not particularly limited as long as it has a radically polymerizable functional group and an alkoxysilyl group.

[0024] The radically polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. From the viewpoint of polymerizability with monomers that form other structural units, a (meth)acryloyl group or a (meth)acryloyloxy group is preferred.

[0025] The alkoxysilyl group is a group having at least one alkoxy group, and examples thereof include a group having three alkoxy groups, a group having two alkoxy groups and one hydrocarbon group, and a group having one alkoxy group and two hydrocarbon groups. From the viewpoint of forming a cured product having excellent solvent resistance even when the curable composition is cured at low temperatures, and from the viewpoint of further improving the patterning properties (lithography properties) of the curable composition, the alkoxysilyl group is preferably a group having three alkoxy groups, or a group having two alkoxy groups and one hydrocarbon group, and more preferably a group having three alkoxy groups. The number of carbon atoms in the alkoxy group is not particularly limited, but is, for example, 1 to 10. From the above viewpoint, it is preferably 1 to 6, more preferably 1 to 4, and even more preferably 1 or 2. The hydrocarbon group is not particularly limited, and examples thereof include a linear or branched aliphatic saturated or aliphatic unsaturated hydrocarbon group, an alicyclic saturated or alicyclic unsaturated hydrocarbon group, and an aryl group, with a linear aliphatic saturated hydrocarbon group being preferred. The number of carbon atoms in the hydrocarbon group is not particularly limited, but is, for example, 1 to 10, and from the above viewpoint, is preferably 1 to 6, more preferably 1 to 4, and even more preferably 1 or 2.

[0026] The radically polymerizable functional group and the alkoxysilyl group may be bonded directly or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched aliphatic saturated or aliphatic unsaturated hydrocarbon groups, alicyclic saturated or alicyclic unsaturated hydrocarbon groups (including bridged rings and fused rings), aromatic hydrocarbon groups, organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.), and organic groups in which two or more of these are bonded. The hydrocarbon group and the organic group may also have various substituents (e.g., halogen groups, hydroxy groups, alkyl groups, alkenyl groups, alkoxy groups, aryl groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.). The linking group is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 2 to 6 carbon atoms.

[0027] The polymer (A) may contain one type of the alkoxysilyl group or two or more types of the alkoxysilyl group.

[0028] In the polymer (A), the content of the repeating structural unit (a2) having an alkoxysilyl group is not particularly limited and is, for example, 5 to 90 mol %, and from the viewpoint of forming a cured product that has excellent solvent resistance even when cured at low temperature, and from the viewpoint of improving the patterning properties (lithography properties) of the curable composition, the content is preferably 10 to 80 mol %, more preferably 30 to 80 mol %, and even more preferably 40 to 70 mol %.

[0029] <Repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group> In addition to the repeating structural unit (a2), the polymer (A) preferably includes a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group. The repeating structural unit (a3) ​​has an acid-dissociable protecting group at its terminal and generates a hydroxyl group upon deprotection. The protecting group can be removed, for example, by an acid generated by an acid generator contained in the curable composition. By including the repeating structural unit (a3) ​​in addition to the repeating structural unit (a2), the polymer (A) can form a cured product that has excellent solvent resistance even when cured at a low temperature (e.g., 100°C or less), and can further improve the patterning properties (lithography properties) of the curable composition. Without being bound by theory, the reason why the above effect is obtained when the polymer (A) contains the repeating structural unit (a3) ​​in addition to the repeating structural unit (a2) is thought to be that the alkoxysilyl group of the repeating structural unit (a2) reacts rapidly with the hydroxyl group generated by deprotection of the repeating structural unit (a3) ​​even at low temperatures, resulting in crosslinking of the polymers (A) together.

[0030] The monomer (a3′) that forms the repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group is not particularly limited as long as it has a radically polymerizable functional group and a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group.

[0031] The radically polymerizable functional group is not particularly limited, and examples thereof include a vinyl group, an allyl group, a (meth)acryloyl group, a (meth)acryloyloxy group, and a (meth)acrylamide group. From the viewpoint of polymerizability with monomers that form other structural units, a (meth)acryloyl group or a (meth)acryloyloxy group is preferred.

[0032] Examples of groups other than alkoxysilyl groups that dissociate with an acid to generate a hydroxyl group include groups having a protecting group such as a tetrahydropyranyl group, a t-butyldimethylsilyl group, a methoxymethyl group, a methoxyethoxymethyl group, an acetyl group, a pivaloyl group, a benzoyl group, and a benzyl group.

[0033] Furthermore, examples of groups other than alkoxysilyl groups that dissociate with an acid to generate a hydroxyl group include groups represented by the following formulas (1) to (4). (In the formula, R 1 are each independently an alkyl group having 1 to 10 carbon atoms. (In the formula, R 2 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a phenyl group, or a cyclohexyl group. (In the formula, R 3 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a phenyl group, and R 4 is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms which may be substituted with a phenyl group, or a phenyl group.

[0034] In the groups represented by the formulas (1), (2) and (4), the alkyl group preferably has 1 to 6 carbon atoms, more preferably 1 to 4 carbon atoms, and even more preferably 1 or 2 carbon atoms.

[0035] The radical polymerizable functional group and the group other than the alkoxysilyl group that dissociates with an acid to generate a hydroxyl group may be bonded directly or via a linking group. The linking group is not particularly limited, and examples thereof include linear or branched aliphatic saturated or aliphatic unsaturated hydrocarbon groups, alicyclic saturated or alicyclic unsaturated hydrocarbon groups (including bridged rings and fused rings), aromatic hydrocarbon groups, organic groups in which some of the carbon atoms constituting the hydrocarbon group are substituted with heteroatoms (e.g., oxygen atoms, nitrogen atoms, sulfur atoms, etc.), and organic groups in which two or more of these are bonded. In addition, the hydrocarbon group and the organic group may have various substituents (e.g., halogen groups, hydroxy groups, alkyl groups, alkenyl groups, alkoxy groups, aryl groups, etc.) or functional groups (e.g., ester bonds, amide bonds, ether bonds, thioether bonds, urethane bonds, etc.). The linking group is preferably an alkylene group having 1 to 15 carbon atoms, more preferably an alkylene group having 1 to 10 carbon atoms, and even more preferably an alkylene group having 2 to 8 carbon atoms, in which some of the carbon atoms may be substituted with heteroatoms and hydrogen atoms may be substituted with the above-mentioned substituents.

[0036] The polymer (A) may contain one or more types of groups other than alkoxysilyl groups that dissociate with an acid to generate hydroxyl groups.

[0037] In the polymer (A), the content of the repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group is not particularly limited and is, for example, 1 to 90 mol %, and from the viewpoint of forming a cured product that has excellent solvent resistance even when cured at low temperature, and from the viewpoint of improving the patterning properties (lithography properties) of the curable composition, the content is preferably 1 to 70 mol %, more preferably 5 to 50 mol %, and even more preferably 5 to 35 mol %.

[0038] <Repeating structural units derived from copolymerized monomers (other structural units)> The polymer (A) may contain repeating structural units derived from copolymerizable monomers such as alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, lauryl (meth)acrylate, and stearyl (meth)acrylate; hydroxyl group-containing (meth)acrylates such as hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate; alkoxy group-containing (meth)acrylates such as ethoxyethyl (meth)acrylate; epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate; alicyclic (meth)acrylates such as cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and dicyclopentenyl (meth)acrylate; maleimides such as cyclohexylmaleimide, phenylmaleimide, methylmaleimide, ethylmaleimide, n-butylmaleimide, and laurylmaleimide; and styrene, provided that the effects of the present invention are not impaired. These repeating structural units may be contained alone or in combination of two or more.

[0039] However, in order to prevent the deterioration of the storage stability of the curable composition, the content of the repeating structural unit having an acid group in the polymer (A) is preferably 1 mol% or less, more preferably 0.5 mol% or less, even more preferably 0.1 mol% or less, and particularly preferably 0 mol%, that is, it is particularly preferable that the polymer (A) does not contain a repeating structural unit having an acid group. Examples of the acid group include a carboxy group, a sulfonic acid group, and a phosphate group. In particular, when the polymer (A) has a repeating structural unit (a2) having an alkoxysilyl group, the reaction between the repeating structural unit (a2) and the repeating structural unit having an acid group may deteriorate the storage stability. Therefore, by having the content of the repeating structural unit having an acid group within the above range, a curable composition having excellent storage stability can be obtained. Furthermore, since the curable composition of the present invention contains a polymer (A) containing a repeating structural unit (a1) having a developable polyoxyalkylene structure and / or a monomer (B) having a polyoxyalkylene structure, the curable composition has developability even when the content of repeating structural units having an acid group in the polymer (A) is low, particularly even when the polymer (A) does not contain a structural unit having an acid group, and in particular has high developability that allows development even with an environmentally friendly developer. Thus, the curable composition of the present invention can achieve both high developability that allows development even with an environmentally friendly developer and high storage stability.

[0040] <Weight-average molecular weight of polymer (A)> The weight-average molecular weight (MW) of the polymer (A) is not particularly limited, but when the curable composition is used as a resist material, from the viewpoint of obtaining good exposure sensitivity and good developability, it is preferably 2,000 to 50,000, more preferably 3,000 to 30,000, even more preferably 4,000 to 15,000, still more preferably 4,000 to 10,000, and particularly preferably 4,000 to 8,000. The weight-average molecular weight is determined by gel permeation chromatography (GPC) in accordance with JIS K 7252-1:2016 and is a value converted using standard polystyrene.

[0041] <Method for Producing Polymer (A)> The polymer (A) can be produced by a known method, for example, by radical polymerization of a monomer composition containing the monomer (a1'), optionally the monomer (a2'), the monomer (a3'), and the copolymerizable monomer. When the polymer (A) is a copolymer, it may be a random copolymer, a block copolymer, an alternating copolymer, or a periodic copolymer.

[0042] [Monomer (B)] The monomer (B) having a polyoxyalkylene structure is the same as the monomer (a1') forming the repeating structural unit (a1) having a polyoxyalkylene structure in the repeating structural unit (a1) having a polyoxyalkylene structure described above, and therefore a description thereof will be omitted. However, when the curable composition of the present invention contains both a polymer (A) and a monomer (B), the monomer (B) contained in the curable composition may be a monomer (B1) having a radical polymerizable functional group and a polyoxyalkylene structure, or a monomer (B2) having a polyoxyalkylene structure without a radical polymerizable functional group, or may contain both a monomer (B1) and a monomer (B2). Furthermore, when the curable composition of the present invention does not contain a polymer (A), the monomer (B) contained in the curable composition may contain a monomer (B1) as an essential component and further contain a monomer (B2). Examples of the monomer (B2) include 2,10-dimethyl-3,5,7,9-tetraoxaundecane, 3,5,7,9,11,13,15,17-octaoxanonadecane, and 1-phenyl-2,4,6,8-tetraoxanonane.

[0043] [Composition of Curable Composition] The curable composition of the present invention may contain a polymer (A) containing a repeating structural unit (a1) having a polyoxyalkylene structure, or may contain a monomer (B) having a polyoxyalkylene structure, or may contain a polymer (A) containing a repeating structural unit (a1) having a polyoxyalkylene structure and a monomer (B) having a polyoxyalkylene structure.

[0044] In the curable composition of the present invention, the content of the polymer (A) is usually about 20 to 99 mass % based on the total solid content of the curable composition, and from the viewpoint of further improving the effects of the present invention, it is preferably 30 to 90 mass %, more preferably 40 to 80 mass %, and even more preferably 50 to 70 mass %.

[0045] In the curable composition of the present invention, the content of the monomer (B) is usually about 20 to 99 mass % based on the total solid content of the curable composition, and from the viewpoint of further improving the effects of the present invention, it is preferably 20 to 90 mass %, more preferably 20 to 60 mass %, and even more preferably 20 to 40 mass %.

[0046] The curable composition of the present invention may contain a polymerizable monomer other than the monomer (B) as long as the effects of the present invention are not impaired. Examples of the polymerizable monomer include, in addition to the copolymerizable monomers listed in the above section <Repeating structural units derived from copolymerizable monomers (other structural units)>, monofunctional monomers such as nonylphenylcarbitol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-ethylhexylcarbitol (meth)acrylate, N-vinylpyrrolidone, and ethoxylated-o-phenylphenol (meth)acrylate; polyfunctional aromatic vinyl monomers such as divinylbenzene, diallyl phthalate, and diallylbenzene phosphonate; (di)ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, trimethylolpropane di(meth)acrylate, and bisphenol A ethylene oxide. Examples of the polymerizable monomer include polyfunctional (meth)acrylates such as addition di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and tris(hydroxyethyl)isocyanurate tri(meth)acrylate; and polyfunctional epoxy monomers such as bisphenol diglycidyl ether, phthalic acid diglycidyl ester, 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, and triglycidyl isocyanurate. These polymerizable monomers may be used alone or in combination of two or more.

[0047] The curable composition of the present invention may also contain polymers and oligomers used in resist materials other than the polymer (A), as long as the effects of the present invention are not impaired.

[0048] The curable composition of the present invention may also contain a photopolymerization initiator, a photopolymerization initiation aid, an acid generator, a thermal polymerization initiator, and the like.

[0049] The photopolymerization initiator is not particularly limited, and examples thereof include benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone; anthraquinones such as 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzophenones such as benzophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides, and xanthones. These photopolymerization initiators may be used alone or in combination of two or more.

[0050] In the curable composition of the present invention, the content of the photopolymerization initiator is not particularly limited, but is preferably 1 to 10 mass %, more preferably 3 to 5 mass %, when the total solid content of the curable composition is taken as 100 mass %.

[0051] The photopolymerization initiator aid is not particularly limited, and examples thereof include trifunctional thiol compounds such as 1,3,5-tris(3-mercaptopropionyloxyethyl)isocyanurate, 1,3,5-tris(3-mercaptobutyloxyethyl)isocyanurate (Karenz MT (registered trademark) NR1, manufactured by Showa Denko K.K.), and trimethylolpropane tris(3-mercaptopropionate); tetrafunctional thiol compounds such as pentaerythritol tetrakis(3-mercaptopropionate) and pentaerythritol tetrakis(3-mercaptobutyrate) (Karenz MT (registered trademark) PEI, manufactured by Showa Denko K.K.); and polyfunctional thiols such as hexafunctional thiol compounds such as dipentaerythritol hexakis(3-propionate). These photopolymerization initiator aids may be used alone or in combination of two or more.

[0052] The acid generator is not particularly limited, and examples thereof include diazonium salts; iodonium salts such as diphenyliodohexafluorophosphate; sulfonium salts such as triphenylsulfonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, and triphenylsulfonium methanesulfonate; sulfonate esters such as 1-phenyl-1-(4-methylphenyl)sulfonyloxy-1-benzoylmethane, 1,2,3-trisulfonyloxymethylbenzene, 1,3-dinitro-2-(4-phenylsulfonyloxymethyl)benzene, and 1-phenyl-1-(4-methylphenylsulfonyloxymethyl)-1-hydroxy-1-benzoylmethane; oxathiazole derivatives, s-triazine derivatives, disulfone derivatives such as diphenyldisulfone, imide compounds, oxime sulfonates, diazonaphthoquinone, and benzointrate. These acid generators may be used alone or in combination of two or more.

[0053] In the curable composition of the present invention, the content of the acid generator is not particularly limited, but is preferably 1 to 10 mass %, more preferably 3 to 8 mass %, and even more preferably 3 to 6 mass %, when the total solid content of the curable composition is taken as 100 mass %.

[0054] Examples of the thermal polymerization initiator include organic peroxides such as cumene hydroperoxide, diisopropylbenzene peroxide, di-t-butyl peroxide, lauryl peroxide, benzoyl peroxide, t-butylperoxyisopropyl carbonate, t-butylperoxy-2-ethylhexanoate, and t-amylperoxy-2-ethylhexanoate; and azo compounds such as 2,2'-azobis(isobutyronitrile), 1,1'-azobis(cyclohexanecarbonitrile), 2,2'-azobis(2,4-dimethylvaleronitrile), and dimethyl 2,2'-azobis(2-methylpropionate). These thermal polymerization initiators may be used alone or in combination of two or more.

[0055] The curable composition of the present invention may also contain a solvent. Examples of the solvent include ethers such as tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, and diethylene glycol dimethyl ether; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; esters such as ethyl acetate, butyl acetate, propylene glycol monomethyl ether acetate, and 3-methoxybutyl acetate; alcohols such as methanol, ethanol, isopropanol, n-butanol, ethylene glycol monomethyl ether, and propylene glycol monomethyl ether; aromatic hydrocarbons such as toluene, xylene, and ethylbenzene; chloroform, dimethyl sulfoxide, and the like. These solvents may be used alone or in combination of two or more. The content of the solvent may be appropriately determined depending on the optimal viscosity of the curable composition when used.

[0056] Furthermore, the curable composition of the present invention may contain known additives such as fillers such as aluminum hydroxide, talc, clay, and barium sulfate, crosslinking agents, surface conditioners (surfactants), dyes, pigments, defoamers, coupling agents, leveling agents, sensitizers, release agents, lubricants, plasticizers, antioxidants, ultraviolet absorbers, flame retardants, polymerization inhibitors, thickeners, and dispersants, within ranges that do not impair the effects of the present invention.

[0057] [Uses of Curable Composition] The curable composition of the present invention can be developed using an environmentally friendly developer, and is therefore suitable for use as a resist material. In particular, the curable composition of the present invention is suitable for use as a negative resist material.

[0058] 2. Cured Product The cured product of the present invention is obtained by curing the curable composition. Examples of methods for producing the cured product include coating the curable composition onto a substrate (substrate) or various functional layers to form a desired shape, and then irradiating the curable composition with light (e.g., ultraviolet light) to cure the curable composition. However, the method is not particularly limited to this method, and known methods can be used depending on the purpose and application of forming the cured product. Curing conditions can be adjusted appropriately depending on the curable composition used.

[0059] The cured product of the present invention is suitably used as a cured product having a pattern shape, such as a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an overcoat film, an optical waveguide, or a planarizing film, and is particularly suitably used as an overcoat film in an organic light-emitting diode (OLED) element.

[0060] The method for forming a cured product having a pattern shape is not particularly limited, and for example, the curable composition is applied to a base material (substrate) or various functional layers, dried to form a coating film, and then photolithography can be used to form the cured product having a pattern shape. As a method for forming a cured product having a pattern shape in photolithography, a negative formation method is preferred, and for example, a photomask is placed on the coating film, and the coating film is photocured by irradiating it with ultraviolet rays, and water is sprayed onto the coating film after ultraviolet irradiation as a developer, and the unexposed parts are dissolved and removed, and the remaining exposed parts are washed with water and developed to form a cured product having a pattern shape. Thereafter, post-baking may be performed.

[0061] 3. Polymer The polymer of the present invention is characterized by comprising a repeating structural unit (a1) having a polyoxyalkylene structure, a repeating structural unit (a2) having an alkoxysilyl group, and a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group. The repeating structural unit (a1), repeating structural unit (a2), and repeating structural unit (a3), as well as the properties of the polymer, are as described above in [Polymer (A)], and therefore will not be described here. The polymer of the present invention is suitable for use as a polymer to be incorporated into a resist material.

[0062] 4. Resist Polymer The resist polymer of the present invention is characterized by comprising a repeating structural unit (a1) having a polyoxyalkylene structure and a repeating structural unit (a2) having an alkoxysilyl group. Preferably, the resist polymer further comprises a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group. The repeating structural unit (a1), repeating structural unit (a2), and repeating structural unit (a3), as well as the properties of the polymer, are as described above in [Polymer (A)], and therefore further description thereof will be omitted.

[0063] The present invention will be described below with reference to examples, but the present invention is not limited to these examples in any way.

[0064] Production Example 1 [Synthesis of Polymer (A-1)] Polymer (A-1) represented by the following formula was synthesized by the following production method.

[0065] A glass flask equipped with a stirrer, reflux condenser, nitrogen inlet tube, and thermometer was charged with 126.9 g of triethoxy(3-methacryloyloxypropyl)silane, 80.0 g of polyethylene glycol methyl ether methacrylate (average number of moles of ethylene oxide added: 9), 22.3 g of phenoxyethyl methacrylate, and 687.7 g of propylene glycol monomethyl ether (PGM). After replacing the gas phase in the system with nitrogen, 45.0 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was added, heated to 65 ° C, and reacted at the same temperature for 8 hours to obtain a solution containing polymer (A-1). Molecular weight measurement by GPC (standard substance: polystyrene) revealed that the weight average molecular weight (Mw) of polymer (A-1) was 5,100.

[0066] Production Examples 2 to 9 [Synthesis of Polymers (A-2) to (A-6) and Polymers (A'-1) to (A'-3)] Polymers (A-2) to (A-6) and polymers (A'-1) to (A'-3) represented by the following formulas were synthesized and their weight-average molecular weights were measured in the same manner as in Production Example 1, except that the structural units and molar ratios in each polymer were adjusted to those shown in Table 1. The structural units, molar ratios (theoretical values), and weight-average molecular weights in each polymer are shown in Table 1. The monomers forming each structural unit in Table 1 are as follows:

[0067] a1-1: polyethylene glycol methyl ether methacrylate (average number of moles of ethylene oxide added: 9) a'1-1: methacrylic acid a2-1: triethoxy(3-methacryloyloxypropyl)silane a2-2: trimethoxy(3-methacryloyloxypropyl)silane a2-3: diethoxymethyl(3-methacryloyloxypropyl)silane a3-1: phenoxyethyl methacrylate a3-2: ethoxylated-o-phenylphenol methacrylate a3-3: 2-(tert-butyloxycarbonyloxy)ethyl methacrylate a4: dicyclopentanyl methacrylate a5: 3,4-epoxycyclohexylmethyl methacrylate a6: bis(methacryloyloxy)propanol

[0068]

[0069]

[0070] Examples 1 to 15, Comparative Examples 1 and 2 [Preparation of Curable Compositions] Curable compositions were prepared by mixing the components shown in Table 2 in the blending ratios (% by mass) shown in Table 2. Mixing was carried out at room temperature while blocking ultraviolet light to prevent the initiation of polymerization. The components shown in Table 2 are as follows: <Polymerizable monomers> B-1: Aronix M-923 (manufactured by Toagosei, a monomer whose main component has an isocyanuric skeleton and two acrylic groups) B-2: Oxol EA-300 (manufactured by Osaka Gas Chemicals, a bifunctional acrylate monomer) B-3: Light Acrylate DCP-A (manufactured by Kyoeisha Chemical, a bifunctional acrylate monomer) <Silane coupling agent> C-1: KBM-9659 (manufactured by Shin-Etsu Chemical Co., Ltd., tris-(trimethoxysilylpropyl)isocyanurate) <Photopolymerization initiator> D-1: TR-PBG-301 (manufactured by TRONLY) <Acid generator> E-1: SP-606 (manufactured by ADEKA)

[0071] Next, the solvent resistance, patterning ability, and storage stability were evaluated by the following methods using each of the curable compositions prepared in Examples 1 to 15 and Comparative Examples 1 and 2. The results are shown in Table 2.

[0072] [Solvent Resistance] Each of the curable compositions prepared in Examples 1 to 15 and Comparative Examples 1 and 2 was applied to a glass substrate (10 cm × 10 cm square) using a spin coater, dried under reduced pressure at room temperature using a vacuum drying device, and further heated on a hot plate at 70°C for 1 minute to completely remove the solvent, forming a coating film (film thickness: 2.0 μm). Thereafter, the obtained coating film was irradiated with light at 1000 mJ / cm using a projection exposure machine. 2 Irradiated (illuminance at 365 nm: 20 mW / cm 2). The coating films of Examples 1 to 14 and Comparative Examples 1 and 2 were then developed for 60 seconds using a 0.05% aqueous TMAH solution, and the coating film of Example 15 was developed using pure water, followed by post-baking at 100°C for 15 minutes to produce substrates with cured films. The 0.05% aqueous TMAH solution contains significantly less TMAH, which has a high environmental impact, than the 2.38% aqueous TMAH solution commonly used as a developer, and can therefore be considered an environmentally friendly developer.

[0073] The prepared substrates with cured films were cut into 5 cm x 5 cm squares to obtain multiple samples. The film thickness at the center of each sample was measured using a stylus profiler. Each sample was then immersed in propylene glycol monomethyl ether acetate (PCMAc) at 25°C for 5 minutes, removed, washed with pure water, and air-blown to remove moisture. The film thickness at the center of each sample was then measured in the same manner as above. The film thickness change rate was calculated from the film thickness of the sample before and after immersion in PCMAc, and the solvent resistance was evaluated according to the following criteria. <Evaluation criteria> A: Film thickness change rate is less than ±5% B: Film thickness change rate is ±5% or more but less than 20% C: Film thickness change rate is ±20% or more but less than 50% D: Film thickness change rate is ±50% or more, or film peeling occurred

[0074] [Patterning Property] Each of the curable compositions prepared in Examples 1 to 15 and Comparative Examples 1 and 2 was applied to a glass substrate (10 cm x 10 cm square) using a spin coater, dried under reduced pressure at room temperature using a vacuum drying device, and further heated on a hot plate at 70°C for 1 minute to completely remove the solvent, forming a coating film (film thickness: 2.0 µm). Thereafter, the obtained coating film was irradiated with light at 40 mJ / cm using a projection exposure machine through a pattern mask on which a plurality of islands of different sizes were formed. 2 Irradiated (illuminance at 365 nm: 20 mW / cm 2). The coating films of Examples 1 to 14 and Comparative Examples 1 and 2 were then developed for 60 seconds using a 0.05% aqueous TMAH solution, and the coating film of Example 15 was developed using pure water, and post-baked at 100°C for 15 minutes to produce a substrate with a cured film pattern. The pattern on the substrate with the cured film pattern was observed with a laser microscope, and the patterning ability was evaluated according to the following criteria. <Evaluation criteria> A: Islands of 50 μm x 100 μm were formed. B: Islands of 1000 μm x 1000 μm or larger were formed. C: Islands of 1000 μm x 1000 μm or larger were not formed (not developed).

[0075] [Storage Stability] Each of the curable compositions prepared in Examples 1 to 15 and Comparative Examples 1 and 2 was divided into two portions and stored for five days at room temperature (25°C) and refrigerated (5°C) conditions, respectively. Substrates with cured film patterns were then prepared from each composition stored under each storage condition using the same method as described above in [Patterning Properties]. Three arbitrary points on a 50 μm × 100 μm island on each of the prepared cured film pattern-bearing substrates in each of the Examples and Comparative Examples were observed, and the pattern shape and finished film thickness were compared between room temperature and refrigerated conditions to evaluate the storage stability of the curable compositions according to the following criteria. For samples where islands could not be formed, only the film thickness was evaluated. <Evaluation Criteria> A: The difference in both the island cross-sectional width and film thickness was less than ±5%. B: The difference in either the island cross-sectional width or film thickness was ±5% or more. C: The difference in both the island cross-sectional width and film thickness was ±5% or more.

[0076]

[0077] As shown in Table 2, the curable compositions (Examples 1 to 15) containing a polymer (A) including a repeating structural unit (a1) having a polyoxyalkylene structure can be developed with good patterning properties even when an environmentally friendly developer is used, and they also have excellent storage stability. On the other hand, the curable composition (Comparative Example 1) containing a polymer including a repeating structural unit having an alkoxysilyl group and the curable composition (Comparative Example 2) containing a polymer including a structural unit having an acid group cannot be developed when an environmentally friendly developer is used.

[0078] The curable composition of the present invention is suitably used as a material for forming photospacers, partition walls, lenses, interlayer insulating films, protective films, overcoat films, optical waveguides, and planarizing films.

Claims

1. A curable composition containing a polymer (A) containing a repeating structural unit (a1) having a polyoxyalkylene structure, and / or a monomer (B) having a polyoxyalkylene structure.

2. The curable composition according to claim 1, wherein the polymer (A) further comprises a repeating structural unit (a2) having an alkoxysilyl group.

3. The curable composition according to claim 2, wherein the polymer (A) further comprises a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group.

4. The curable composition according to claim 1, which is a resist material.

5. A cured product obtained from the curable composition according to any one of claims 1 to 4.

6. The cured product according to claim 5, which is a photospacer, a partition wall, a lens, an interlayer insulating film, a protective film, an overcoat film, an optical waveguide, or a planarizing film.

7. A polymer comprising a repeating structural unit (a1) having a polyoxyalkylene structure, a repeating structural unit (a2) having an alkoxysilyl group, and a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group.

8. A resist polymer comprising a repeating structural unit (a1) having a polyoxyalkylene structure and a repeating structural unit (a2) having an alkoxysilyl group.

9. The resist polymer according to claim 8, further comprising a repeating structural unit (a3) ​​having a group other than an alkoxysilyl group that dissociates with an acid to generate a hydroxyl group.

Images