S硬化性組成物、硬化物及び積層体

Abstract

To provide a curable composition capable of stably obtaining a cured product that is hardly affected by temperature when an uneven structure is formed by curing, and excellent in delustering properties; and to provide the cured product formed by curing the curable composition, and a laminate formed by having the cured product laminated on a surface of a base material.SOLUTION: Provided is a curable composition including a polymer (A) having an active group that generates radicals by irradiation with active energy rays, and methacrylate (B). Provided is a cured product formed by curing the curable composition. Provided is a laminate formed by having the cured product laminated on a surface of a base material.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a cured product having an uneven surface structure, a laminate obtained by laminating the cured product on the surface of a substrate, and a curable composition capable of forming the cured product. [Background technology]

[0002] Known methods for improving design and visibility by forming a fine uneven structure on the surface of a substrate to impart an iridescent color or matte finish, in which the color changes depending on the observation angle, include, for example, a method in which a curable composition having fine particles dispersed therein is applied to the substrate and cured, a method in which a thin metal film is vapor-deposited onto the substrate, and a method in which a curable composition is applied to a substrate and cured to produce a cured product with fine wrinkles on the surface. For example, Patent Document 1 describes a technology in which a curable composition is applied to a substrate, and then irradiated with active energy rays to form a fine uneven structure on the surface of the cured product, thereby imparting rainbow color and matte finish. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2019-131717 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, according to the study by the present inventors, it was found that the arithmetic mean roughness (Ra) of the uneven surface structure of the curable composition used in the method described in Patent Document 1 changes significantly when the temperature during curing changes. Since the temperature during curing is affected by the external environment, it is difficult to industrially produce products of consistent quality. The present invention aims to provide a curable composition that is less affected by temperature when forming a concave-convex structure by curing and can stably give a cured product with excellent matte properties, a cured product obtained by curing the curable composition, and a laminate in which the cured product is laminated on the surface of a substrate. [Means for solving the problem]

[0005] [1] A curable composition comprising a polymer (A) having an active group that generates radicals upon irradiation with active energy rays, and a methacrylate (B). [2] The curable composition according to [1], wherein the polymer (A) contains a structural unit derived from a (meth)acrylic acid ester having an active group. [3] The curable composition according to [1] or [2], wherein the active group that generates radicals upon irradiation with active energy rays is one or more selected from the group consisting of a benzophenone group, an acetophenone group, a benzoin group, an α-hydroxyketone group, an α-aminoketone group, an α-diketone group, an α-diketone dialkyl acetal group, an anthraquinone group, a thioxanthone group, and a phosphine oxide group. [4] The curable composition according to any one of [1] to [3], wherein the polymer (A) further comprises a structural unit derived from an alkyl (meth)acrylate ester having an alkyl group having 4 or more carbon atoms. [5] The curable composition according to any one of [1] to [4], wherein the polymer (A) has a structural unit derived from a (meth)acrylic acid ester having a hydrogen-donor functional group. [6] The curable composition according to any one of [1] to [5], wherein the polymer (A) has a weight average molecular weight of 1,000 to 500,000. [7] The curable composition according to any one of [1] to [6], wherein the methacrylate (B) contains a di- or higher functional methacrylate. [8] The curable composition according to any one of the above [1] to [7], further comprising an acrylate (C). [9] The curable composition according to any one of the above [1] to [8], further comprising an organic solvent (D).

[10] A cured product obtained by curing the curable composition according to any one of the above [1] to [9].

[11] The cured product according to

[10] , which is a film-like product having an uneven surface structure.

[12] A laminate comprising a substrate and the cured product according to

[10] or

[11] laminated on the surface of the substrate. Effect of the Invention

[0006] The curable composition of the present invention is less affected by temperature when forming a concave-convex structure by curing, and can stably give a cured product with excellent matte finish; a cured product obtained by curing the curable composition; and a laminate in which the cured product is laminated on the surface of a substrate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] Hereinafter, an embodiment of the present invention will be described in detail. In the present invention, "(meth)acrylate" is a general term for acrylate or methacrylate, and "(meth)acrylic" is a general term for acrylic and methacrylic. The symbol "~" indicating a range of values ​​means that the values ​​before and after it are included as the lower and upper limits.

[0008] <Curable composition> The curable composition of the present invention contains a polymer (A) having an active group that generates radicals upon irradiation with active energy rays (hereinafter referred to as polymer (A)), and a methacrylate (B). The curable composition may comprise an acrylate (C). The curable composition may optionally contain an organic solvent (D). The curable composition may contain other components in addition to those described above, if necessary.

[0009] <Polymer (A)> The polymer (A) has an active group (hereinafter, referred to as an active group) that generates radicals when irradiated with active energy rays. The active group is a group having a structure that generates radicals when irradiated with active energy rays, in other words, a structure having photopolymerization initiation. Examples of the structure having photopolymerization initiation include hydrogen abstraction type, electron transfer type, and intramolecular cleavage type. In the present invention, the radical generated from the active group reacts with the methacrylate (B) to form a crosslinked structure. (active group) Examples of active groups include benzophenone groups, acetophenone groups, benzoin groups, α-hydroxyketone groups (e.g., a group in which one hydrogen atom has been removed from the "hydroxyl group in 2-hydroxyethoxy" of 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-methylpropanone), α-aminoketone groups, α-diketone groups, α-diketone dialkyl acetal groups, anthraquinone groups, thioxanthone groups, and phosphine oxide groups. Among these, benzophenone groups, acetophenone groups, and α-hydroxyketone groups are preferred because they are less susceptible to oxygen inhibition during curing and provide good surface curing properties when forming a concave-convex layer.

[0010] The active group may be present at the terminal of the main chain of the polymer (A), or may be present in a constituent unit derived from a monomer constituting the polymer (A). It is preferable that the polymer (A) has multiple active groups in the molecule, because this makes it possible to increase the concentration of active groups near the coating film surface, the coating film is less susceptible to oxygen inhibition and thus has improved curability, and the cured surface is more likely to have an uneven structure such as a wrinkled structure.

[0011] The polymer (A) having a plurality of active groups is preferably a polymer having a structural unit derived from a monomer having an active group. The monomer having an active group may be a compound having an active group and a radically polymerizable group. The radically polymerizable group may be a functional group containing a radically polymerizable unsaturated bond such as a carbon-carbon double bond. (Monomer having active group) As the monomer having an active group, a (meth)acrylic acid ester is preferable from the viewpoint of ease of synthesis of the polymer (A) and ease of adjustment of the amount of the active group introduced. Examples of such a (meth)acrylic acid ester include 4-methacryloyloxybenzophenone and 2-[4-(2-hydroxy-2-methyl-1-oxopropyl)phenoxy]ethyl methacrylate.

[0012] The proportion of the constituent units derived from monomers having active groups relative to the total mass of all units constituting the polymer (A) is preferably in the range of 1 to 90 mass%, more preferably 5 to 80 mass%, further preferably 15 to 70 mass%, and particularly preferably 30 to 60 mass%. If this proportion is within the above range, the curability can be improved and an uneven structure can be effectively formed.

[0013] (Monomers having an alkyl group with 4 or more carbon atoms) The polymer (A) preferably has a structural unit derived from a monomer having an alkyl group having 4 or more carbon atoms in addition to a structural unit derived from a monomer having an active group. If the polymer (A) has this unit, when a coating film of the curable composition is formed, the polymer (A) is likely to segregate to the surface side of the coating film. This segregation makes the curing reaction inside the coating film (substrate side) less susceptible to oxygen inhibition, improving the curability. For example, it can be cured with a low exposure dose, and even a thin coating film that tends to be easily inhibited by oxygen can be cured well.

[0014] The alkyl group having 4 or more carbon atoms may be linear, branched, or cyclic. The cyclic alkyl group may be monocyclic or polycyclic. From the viewpoint of more effectively segregating the polymer (A) on the surface of the coating film, the alkyl group is preferably linear. The carbon number of the alkyl group having 4 or more carbon atoms is preferably in the range of 4 to 30, more preferably in the range of 6 to 20, and even more preferably in the range of 12 to 18, from the viewpoint of more effectively segregating the polymer (A) on the surface of the coating film.

[0015] Examples of monomers having an alkyl group having 4 or more carbon atoms include compounds having an alkyl group having 4 or more carbon atoms and a radical polymerizable group. Examples of such compounds include (meth)acrylic acid alkyl esters, fumaric acid dialkyl esters, maleic acid dialkyl esters, and aliphatic olefins. From the viewpoints of ease of synthesis and ease of adjusting the amount of the alkyl group having 4 or more carbon atoms introduced, (meth)acrylic acid alkyl esters are preferred.

[0016] Examples of such (meth)acrylic acid alkyl esters include butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, decyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, and isodecyl (meth)acrylate. (meth)acrylate, dodecyl (meth)acrylate, myristyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, tridecyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tricyclodecane (meth)acrylate, dicyclopentanyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, and the like. Among these, it is preferable to include a (meth)acrylic acid alkyl ester having a linear alkyl group having 4 or more carbon atoms. As the (meth)acrylic acid alkyl ester having a linear alkyl group having 4 or more carbon atoms, it is preferable that the number of carbon atoms in the alkyl group is within the above-mentioned preferred range, and taking into consideration ease of production, etc., 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, dodecyl (meth)acrylate, and stearyl (meth)acrylate are more preferable, and stearyl (meth)acrylate is particularly preferable. These (meth)acrylic acid alkyl esters may be used alone or in combination of two or more.

[0017] The proportion of the constituent units derived from monomers having an alkyl group having 4 or more carbon atoms relative to the total mass of all units constituting the polymer (A) is preferably 80 mass% or less, more preferably 1 to 55 mass%, further preferably 5 to 50 mass%, and particularly preferably 8 to 40 mass%. If this proportion is within the above range, the curability can be improved and an uneven structure can be effectively formed.

[0018] (Monomers containing fluorine or silicon atoms) In order to more effectively segregate polymer (A) on the surface of the coating film, polymer (A) may contain a structural unit derived from a monomer containing a fluorine atom or a silicon atom in addition to or instead of a structural unit derived from a monomer having an alkyl group having 4 or more carbon atoms. The fluorine atom-containing monomer is preferably a (meth)acrylic acid ester containing a fluorine atom, more preferably a (meth)acrylic acid ester having a perfluoroalkyl group, the number of carbon atoms of which is preferably 4 or more. The silicon atom-containing monomer is preferably a (meth)acrylic acid ester containing a silicon atom, and more preferably a (meth)acrylic acid ester having a polydimethylsiloxane chain.

[0019] The proportion of the constituent units derived from monomers containing fluorine atoms or silicon atoms to the total mass of all units constituting the polymer (A) is preferably 80 mass% or less, more preferably 1 to 55 mass%, further preferably 5 to 50 mass%, and particularly preferably 8 to 40 mass%. If this proportion is within the above range, the curability can be improved and an uneven structure can be effectively formed.

[0020] (Monomers Having Hydrogen Donor Functional Groups) The polymer (A) may have a structural unit derived from a monomer having a hydrogen donor functional group, if necessary. In particular, when the active group contains a hydrogen abstraction type, it is preferable to contain a structural unit derived from a monomer having a hydrogen donor functional group. If the polymer (A) has this unit, the coating film of the curable composition is effectively cured from the surface, so that the curability is improved and the uneven structure is easily formed. Examples of the hydrogen donating functional group include a hydroxyl group, an amino group, a mercapto group, and an amide group. Among these, a hydroxyl group, an amino group, or an amide group is preferred from the viewpoint of the curing reaction proceeding particularly efficiently, improving the curability, or facilitating the formation of an uneven structure.

[0021] Examples of the monomer having a hydrogen donor functional group include a compound having a hydrogen donor functional group and a radical polymerizable group. From the viewpoints of ease of synthesis of the compound and ease of adjustment of the amount of hydrogen donor functional group to be introduced, a (meth)acrylic acid ester having a hydrogen donor functional group is preferred. Examples of monomers having a hydrogen donating functional group include hydroxyl group-containing monomers such as 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, monobutyl hydroxyl fumarate, and monobutyl hydroxy itaconate; N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, N-vinyl caprolactam, N-vinyl pyrrolidone, and N-isopropyl (meth)acrylamide. Examples of the monomers include amino group- or amide group-containing monomers such as N,N-dimethylaminoethyl (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylate, 2-[(butylamino)carbonyl]oxy]ethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylamide, N,N-diethylaminopropyl (meth)acrylamide, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N,N-diethylaminopropyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylamide, N,N-diethylaminoethyl (meth)acrylamide, (meth)acryloylmorpholine, and vinylacetamide. Among these, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, (N,N-dimethylacrylamide, N,N-dimethylaminoethyl (meth)acrylate, and N,N-diethylaminoethyl (meth)acrylate are preferred because they have an excellent curing acceleration effect when used in combination with an active group, and N,N-diethylaminoethyl (meth)acrylate is more preferred because it is easy to enlarge the uneven structure. These compounds may be used alone or in combination of two or more.

[0022] The proportion of the constituent units derived from the monomer having a hydrogen donor functional group relative to the total mass of all units constituting the polymer (A) is preferably 80 mass% or less, more preferably 1 to 40 mass%, further preferably 3 to 35 mass%, and particularly preferably 5 to 30 mass%. If this proportion is within the above range, the curability can be improved and an uneven structure can be effectively formed.

[0023] (Weight average molecular weight) The weight average molecular weight (Mw) of the polymer (A) is preferably in the range of 1000 to 500000, more preferably 3000 to 50000, and further preferably 5000 to 30000. When Mw is within the above range, the coatability and curability of the curable composition tend to be further improved, and the ease of forming an uneven structure tends to be further improved. The Mw of the polymer (A) is a value calculated in terms of standard polystyrene as measured by gel permeation chromatography (GPC). Detailed measurement conditions are as described in the Examples below.

[0024] (Other monomers) The polymer (A) may further contain a structural unit derived from a monomer other than the above, if necessary. Examples of the other monomer include a compound having a radical polymerizable group but not having an active group, an alkyl group having 4 or more carbon atoms, a fluorine atom, a silicon atom, or a hydrogen donor functional group. Examples of other monomers include carboxyl group-containing monomers such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, citraconic acid, and salts thereof; (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, and propyl (meth)acrylate; nitrogen-containing monomers such as (meth)acrylonitrile; styrene-based compounds such as styrene, α-methylstyrene, divinylbenzene, and vinyltoluene; vinyl esters such as vinyl propionate and vinyl acetate; silicon-containing monomers such as γ-methacryloxypropyltrimethoxysilane and vinyltrimethoxysilane; phosphorus-containing vinyl monomers; vinyl halides such as vinyl chloride and vinylidene chloride; and conjugated dienes such as butadiene.

[0025] The content of active groups per gram of polymer (A) is preferably in the range of 0.1 to 3.5 mmol / g, more preferably 0.3 to 3.0 mmol / g, further preferably 0.5 to 2.7 mmol / g, and particularly preferably 1.0 to 2.5 mmol / g. When the content of active groups is within the above range, curability is excellent and unevenness can be formed more effectively.

[0026] (glass transition temperature) The glass transition temperature (Tg) of the polymer (A) is preferably in the range of −30 to 150° C., more preferably 0 to 120° C., and further preferably 25 to 100° C. When Tg is within the above range, curability tends to be improved and the ease of forming a concave-convex structure tends to be improved.

[0027] (Production of Polymer (A)) Typically, the polymer (A) can be produced by polymerizing the raw material monomer in the presence of a polymerization initiator. If necessary, a chain transfer agent may be used in the polymerization. Examples of the polymerization method include solution polymerization, suspension polymerization, bulk polymerization, and emulsion polymerization, and among these, solution polymerization is preferred because of its simple operation and high productivity.

[0028] (Content of polymer (A)) The content of polymer (A) in the curable composition of the present invention is preferably from 0.5 to 25.0 mass%, more preferably from 0.7 to 20.0 mass%, even more preferably from 1.0 to 15.0 mass%, particularly preferably from 2.0 to 12.0 mass%, and most preferably from 3.0 to 10.0 mass%, relative to the non-volatile content, from the viewpoints of imparting an uneven structure to the surface of the cured product and achieving good active energy ray curability. The non-volatile content of the curable composition is the total mass of components other than the solvent such as the organic solvent. The proportion of the non-volatile content in the curable composition can be measured by a conventionally known method, and can be calculated from the change in weight when, for example, 1 g of the composition is spread and heated at 100° C. for 1 hour to volatilize the organic solvent.

[0029] <Methacrylate (B)> The methacrylate (B) is not particularly limited as long as it is a methacrylic acid ester, and may be any of monofunctional methacrylate, bifunctional methacrylate, and trifunctional or higher polyfunctional methacrylate. As the methacrylate (B), a commercially available active energy ray curable resin material containing one or more methacrylic acid esters may also be used. The methacrylate (B) is a component that contributes to the ease of forming an uneven structure on the surface of the cured product, improving scratch resistance, and improving hardness.

[0030] Examples of monofunctional methacrylates include, but are not limited to, alkyl methacrylates such as methyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, and isobornyl methacrylate; hydroxyalkyl methacrylates such as hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate; alkoxyalkyl methacrylates such as methoxyethyl methacrylate, ethoxyethyl methacrylate, methoxypropyl methacrylate, and ethoxypropyl methacrylate; aromatic methacrylates such as benzyl methacrylate and phenoxyethyl methacrylate; amino group-containing methacrylates such as diaminoethyl methacrylate and diethylaminoethyl methacrylate; ethylene oxide-modified methacrylates such as methoxyethylene glycol methacrylate, phenoxypolyethylene glycol methacrylate, and phenylphenol ethylene oxide-modified methacrylate; glycidyl methacrylate, tetrahydrofurfuryl methacrylate, and methacrylic acid.

[0031] The bifunctional methacrylate is not particularly limited, but examples thereof include alkanediol dimethacrylates such as 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, and tricyclodecane dimethylol dimethacrylate; bisphenol-modified dimethacrylates such as bisphenol A ethylene oxide-modified dimethacrylate and bisphenol F ethylene oxide-modified dimethacrylate; polyethylene glycol dimethacrylate; polypropylene glycol dimethacrylate; urethane dimethacrylate; and epoxy dimethacrylate. Among these, in consideration of the ease of forming a wrinkled uneven structure, a structure without branching is preferable, alkyldiol dimethacrylate is more preferable, and alkyldiol dimethacrylate having 4 to 18 carbon atoms is even more preferable.

[0032] Examples of the trifunctional or higher polyfunctional methacrylate include, but are not limited to, ethylene oxide-modified methacrylates such as dipentaerythritol hexamethacrylate, pentaerythritol tetramethacrylate, ditrimethylolpropane tetramethacrylate, pentaerythritol trimethacrylate, trimethylolpropane trimethacrylate, ethylene oxide-modified dipentaerythritol hexamethacrylate, and ethylene oxide-modified pentaerythritol tetramethacrylate, isocyanuric acid-modified trimethacrylates such as ε-caprolactone-modified tris(acryloxyethyl)isocyanurate, and urethane methacrylates such as pentaerythritol trimethacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol trimethacrylate toluene diisocyanate urethane prepolymer, and dipentaerythritol pentamethacrylate hexamethylene diisocyanate urethane prepolymer. Among these, in consideration of the ease of forming a wrinkled uneven structure, ethylene oxide modified types and trifunctional methacrylates such as pentaerythritol trimethacrylate and trimethylolpropane trimethacrylate are preferred. The above methacrylates may be used alone or in combination of two or more kinds.

[0033] The content of the methacrylate (B) in the curable composition of the present invention is preferably 0.5% by mass or more and 70.0% by mass or less, more preferably 0.7% by mass or more and 65.0% by mass or less, even more preferably 1.0% by mass or more and 60.0% by mass or less, particularly preferably 2.0% by mass or more and 50.0% by mass or less, and most preferably 3.0% by mass or more and 30.0% by mass or less, based on the non-volatile content of the curable composition, from the viewpoint of good curability. By using it within this range, the hardness of the cured product becomes sufficient and the scratch resistance is improved. In addition, the effect of the temperature during curing can be suppressed, and the uneven structure can be stably formed even if the temperature changes.

[0034] <Acrylate (C)> The curable composition of the present invention may contain an acrylate (C). The acrylate (C) is not particularly limited as long as it is an acrylic acid ester, and may be any of a monofunctional acrylate, a difunctional acrylate, and a multifunctional acrylate having three or more functional groups. As the acrylate (C), a commercially available active energy ray curable resin material containing one or more acrylic acid esters may also be used.

[0035] The monofunctional acrylate is not particularly limited, but examples thereof include alkyl acrylates such as methyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, cyclohexyl acrylate, and isobornyl acrylate; hydroxyalkyl acrylates such as hydroxyethyl acrylate, hydroxypropyl acrylate, and hydroxybutyl acrylate; alkoxyalkyl acrylates such as methoxyethyl acrylate, ethoxyethyl acrylate, methoxypropyl acrylate, and ethoxypropyl acrylate; aromatic acrylates such as benzyl acrylate and phenoxyethyl acrylate; amino group-containing acrylates such as diaminoethyl acrylate and diethylaminoethyl acrylate; ethylene oxide-modified acrylates such as methoxyethylene glycol acrylate, phenoxypolyethylene glycol acrylate, and phenylphenol ethylene oxide-modified acrylate; glycidyl acrylate, tetrahydrofurfuryl acrylate, and acrylic acid.

[0036] The bifunctional acrylate is not particularly limited, but examples thereof include alkanediol diacrylates such as 1,4-butanediol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, and tricyclodecane dimethylol diacrylate; bisphenol-modified diacrylates such as bisphenol A ethylene oxide-modified diacrylate and bisphenol F ethylene oxide-modified diacrylate; polyethylene glycol diacrylate, polypropylene glycol diacrylate, urethane diacrylate, and epoxy diacrylate. Among these, in consideration of the ease of forming a wrinkled uneven structure, a structure without branching is preferable, alkyldiol diacrylate is more preferable, and alkyldiol diacrylate having 4 to 18 carbon atoms is even more preferable.

[0037] The trifunctional or higher polyfunctional acrylate is not particularly limited, but examples thereof include ethylene oxide-modified acrylates such as dipentaerythritol hexaacrylate, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, ethylene oxide-modified dipentaerythritol hexaacrylate, and ethylene oxide-modified pentaerythritol tetraacrylate, isocyanuric acid-modified triacrylates such as ε-caprolactone-modified tris(acryloxyethyl)isocyanurate, and urethane acrylates such as pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer, pentaerythritol triacrylate toluene diisocyanate urethane prepolymer, and dipentaerythritol pentaacrylate hexamethylene diisocyanate urethane prepolymer. Among these, ethylene oxide modified type and trifunctional acrylate are preferred in consideration of the ease of forming a wrinkled uneven structure. Also, in consideration of the hardness and scratch resistance of the cured film, it is preferred to contain a hexafunctional or higher acrylate, such as dipentaerythritol hexaacrylate and ethylene oxide modified dipentaerythritol hexaacrylate, and further preferred is a modified type dipentaerythritol hexaacrylate such as ethylene oxide modified, since it is easier to form unevenness. The above acrylates may be used alone or in combination of two or more kinds.

[0038] The content of the acrylate (C) in the curable composition of the present invention is preferably 5.0% by mass or more and 99.0% by mass or less, more preferably 15.0% by mass or more and 98.6% by mass or less, even more preferably 25.0% by mass or more and 98.0% by mass or less, particularly preferably 38.0% by mass or more and 96.0% by mass or less, and most preferably 60.0% by mass or more and 94.0% by mass or less, based on the non-volatile content of the curable composition, from the viewpoint of good curability. By using it within this range, the hardness of the cured product becomes sufficient and the scratch resistance is improved. In particular, the hardness of the cured product can be increased by making the acrylate having hexafunctional or higher 30.0% by mass or more, more preferably 50.0% by mass or more, and even more preferably 70.0% by mass or more.

[0039] <Organic solvent (D)> The curable composition of the present invention may contain an organic solvent (D). By containing the organic solvent (D), the workability when applying the curable composition of the present invention to a substrate is improved. Examples of the organic solvent (D) include aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone, acetone, methyl isobutyl ketone, and cyclohexanone; ether solvents such as diethyl ether, isopropyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol monomethyl ether, anisole, and phenetole; ester solvents such as ethyl acetate, butyl acetate, isopropyl acetate, and ethylene glycol diacetate; amide solvents such as dimethylformamide, diethylformamide, and N-methylpyrrolidone; cellosolve solvents such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve; alcohol solvents such as methanol, ethanol, propanol, isopropanol, and butanol; and halogen solvents such as dichloromethane and chloroform. The organic solvent (D) may be used alone or in combination of two or more kinds. Among these solvents, ester-based solvents, ether-based solvents, alcohol-based solvents and ketone-based solvents are preferred in terms of improving workability during coating.

[0040] The content of the organic solvent (D) in the curable composition of the present invention is preferably from 10 parts by mass to less than 1,900 parts by mass, and more preferably from 40 parts by mass to less than 400 parts by mass, relative to 100 parts by mass of the nonvolatile content of the curable composition, in terms of improving operability in a coating operation.

[0041] <Photopolymerization initiator> When the curable composition of the present invention is irradiated with active energy rays, radicals are generated from the active groups of the polymer (A), so that the composition has photocurability even without a separate photopolymerization initiator. However, a photopolymerization initiator may be included to promote curing. As the photopolymerization initiator, a compound having a molecular weight of less than 1000 is preferable. As the photopolymerization initiator, for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzyl diphenyl disulfide, dibenzyl, diacetyl, anthraquinone, naphthoquinone, 3,3'-dimethyl-4-methoxybenzophenone, benzophenone, p,p'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, pivaloin ethyl ether, benzyl dimethyl ketal, 1,1-dichloroacetophenone, pt-butyl dichloroacetophenone, benzoin methyl ether, benzoin ethyl ... Examples of suitable acetophenones include cetophenone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-diethylthioxanthone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-dichloro-4-phenoxyacetophenone, phenylglyoxylate, α-hydroxyisobutylphenone, dibenzosparone, 1-(4-isopropylphenyl)-2-hydroxy-2-methyl-1-propanone, 2-methyl-[4-(methylthio)phenyl]-2-morpholino-1-propanone, tribromophenyl sulfone, and tribromomethylphenyl sulfone.

[0042] The photopolymerization initiator is preferably added to an extent that it does not cure preferentially to the polymer (A). The amount of the photopolymerization initiator added is preferably 3% by mass or less, more preferably 2% by mass or less, even more preferably 1% by mass or less, and particularly preferably 0.5% by mass or less, based on 100 parts by mass of the nonvolatile content of the curable composition.

[0043] <Leveling agent> The curable composition of the present invention may contain a suitable amount of a leveling agent to improve the appearance of the cured product. Examples of the leveling agent include acrylic leveling agents, silicone leveling agents, and fluorine leveling agents. The leveling agent may be used alone or in combination of two or more types.

[0044] <Inorganic particles> The curable composition of the present invention may contain an appropriate amount of inorganic particles in order to further improve the matte property of the cured product. The average primary particle diameter of the inorganic particles is preferably 0.01 to 10 μm. The inorganic particles may be particles whose surfaces are modified with a silane coupling agent having a reactive group such as a (meth)acryloyl group. The surface-modified particles can be produced, for example, by reacting a silane coupling agent having a reactive group such as a (meth)acryloyl group with inorganic particles in the presence of a silane coupling reaction catalyst such as an acid, a base, or aluminum acetylacetonate at 25 to 120° C. for about 1 to 24 hours. Examples of the inorganic particles include silica, alumina, and zirconia. Among them, silica is preferred.

[0045] <Other ingredients> The curable composition of the present invention may contain, for example, a polymerization accelerator such as a compound containing a thiol group, an antistatic agent, a plasticizer, a surfactant, an antioxidant, and an ultraviolet absorber, as long as the effects of the present invention are not impaired.

[0046] <Method of producing curable composition> The curable composition of the present invention can be produced by mixing the polymer (A) and the methacrylate (B), and, if necessary, the acrylate (C), the organic solvent (D), the leveling agent, the inorganic particles, the photopolymerization initiator, and other components.

[0047] <Cured product> The cured product of the present invention can be obtained, for example, by applying the curable composition to a substrate, drying the coating film, and irradiating it with active energy rays. Since the concentration of the polymer (A) is likely to be high on the surface side of the coating film before curing, when the surface side is irradiated with active energy rays, radicals are generated from the active groups of the polymer (A), and the reaction between the methacrylates (B) having radical polymerizable groups proceeds with the generated radicals as the starting point, so that the surface of the coating film is cured first to form a cured coating. After that, the inside of the coating film reacts and shrinks during curing, and it is considered that the shrinkage stress at that time causes the cured coating film to buckle, resulting in the development of a wrinkled uneven structure. Usually, the surface of the obtained film-like cured product (hereinafter also referred to as cured film) has a wrinkled uneven structure (non-smooth structure) and therefore has a matte finish.

[0048] The thickness of the cured film (concave-convex layer) is preferably in the range of 0.1 to 100 μm, more preferably 0.2 to 20 μm, further preferably 0.3 to 10 μm, and particularly preferably 0.3 to 7 μm. If the thickness of the cured product is within the above range, it is easy to achieve a matte finish with sufficiently little reflection of external light. The thickness of the cured film indicates the maximum thickness of the concave-convex layer, and is determined by cross-sectional observation using an electron microscope.

[0049] The arithmetic mean roughness (Ra) of the surface of the cured film is preferably 0.05 μm or more, more preferably 0.08 μm or more, even more preferably 0.10 μm or more, particularly preferably 0.15 μm or more, and most preferably 0.2 μm or more, and although there is no particular upper limit, it is preferably 5 μm. When it is in the above range, it has excellent matte properties.

[0050] The haze of the cured film measured by the method described in the Examples below is preferably 1% or more, more preferably 3% or more, even more preferably 5% or more, particularly preferably 10% or more, and most preferably 20% or more, with the upper limit being, for example, 99%. The larger the haze, the more improved the matte properties tend to be. When the matte property is important, the haze is preferably 40% or more, more preferably 50% or more, and even more preferably 60% or more, with the upper limit being, for example, 99%. Depending on the application of the cured product, the higher the haze, the more preferable it may be. If the haze is equal to or more than the lower limit, it is easy to achieve a high degree of matte property.

[0051] The 60° gloss (60° specular gloss) of the surface of the cured film, measured by the method described in the examples below, is preferably 50 or less, more preferably 40 or less, even more preferably 30 or less, particularly preferably 25 or less, and most preferably 20 or less. The lower the gloss, the more improved the matte properties tend to be. Similarly, the 20° gloss is preferably 30 or less, more preferably 20 or less, even more preferably 15 or less, particularly preferably 10 or less, and most preferably 8 or less, with the lower the better. When the gloss is equal to or less than the upper limit, the matte properties are excellent.

[0052] The cured film is preferably light-transmitting. The total light transmittance measured by the method described in the Examples below is preferably 50% or more, more preferably 60% or more, even more preferably 70% or more, particularly preferably 80% or more, and most preferably 90% or more, and the higher the transmittance, the better (the upper limit is 100%).

[0053] (base material) Examples of the substrate to which the curable composition is applied include various polymer films, plates, and molded articles of other shapes. Examples of the polymer film include triacetyl cellulose (TAC) film, polyethylene terephthalate (PET) film, diacetylene cellulose film, acetate butyrate cellulose film, polyethersulfone film, polyacrylic polymer film, polyurethane polymer film, polycarbonate film, polysulfone film, polyether film, polymethylpentene film, polyetherketone film, (meth)acrylonitrile film, and cycloolefin polymer (COP) film. Examples of the polymer plate and polymer molded article include plates and molded articles made of acrylic, triacetyl cellulose, polyethylene terephthalate, diacetylene cellulose, acetate butyrate cellulose, polyethersulfone, polyurethane, polycarbonate, polysulfone, polyether, polymethylpentene, polyetherketone, and (meth)acrylonitrile. Inorganic materials such as glass can also be used as the substrate. The thickness of the substrate can be appropriately selected depending on the application, but generally, a thickness of about 25 to 10,000 μm is used.

[0054] (Method of producing the cured product) The method for applying the curable composition to the substrate is not particularly limited, and examples thereof include dip coating, air knife coating, curtain coating, spin coating, roller coating, bar coating, wire bar coating, gravure coating, and spray coating.

[0055] The curable composition applied to the substrate is preferably dried before being cured by irradiation with active energy rays. When drying, the drying temperature is preferably 30 to 200°C, more preferably 40 to 150°C. The drying time is preferably 0.01 to 30 minutes, more preferably 0.1 to 10 minutes. By drying in advance, the solvent in the coating film can be effectively removed, and the concentration of the polymer (A) on the surface side of the coating film increases, making it easier for an uneven structure to appear on the surface of the cured product.

[0056] Examples of active energy rays include ultraviolet rays, α rays, β rays, and γ rays, of which ultraviolet rays are preferred. The amount of irradiation of the active energy ray can be appropriately selected depending on the type of the active energy ray to be irradiated. When ultraviolet light is used, the cumulative amount of irradiation is 100 mJ / cm 2 More than 3000mJ / cm 2 Less than 200 mJ / cm is preferable. 2 More than 2000mJ / cm 2 More preferably, the illuminance is 50 mW / cm or less. 2 More than 600mW / cm 2 Less than 75mW / cm is preferable. 2 More than 450mW / cm 2 Less than 100 mW / cm is more preferable. 2 More than 300mW / cm 2 The following are more preferred: Examples of the light source include a medium pressure mercury lamp, a high pressure mercury lamp, an ultra-high pressure mercury lamp, an electrodeless lamp, a metal halide lamp, an electron beam using a scanning or curtain type electron beam acceleration path, a high pressure mercury lamp, and a low pressure mercury lamp.

[0057] When the coating is cured by irradiating it with active energy rays, if the concentration of polymer (A) on the surface side of the coating is made high in advance, the surface of the coating will cure first to form a cured coating. After that, the inside of the coating will cure and shrink, and it is thought that the shrinkage stress at that time causes the cured coating to buckle, resulting in the appearance of a wrinkled uneven structure.

[0058] The arithmetic mean roughness (Ra) of the surface unevenness structure decreases when the curing time inside the coating film is shortened, and increases when the curing time is extended. The curing time can be adjusted by the amount of polymer (A), methacrylate (B), and photopolymerization initiator, the intensity of the active energy rays, etc.

[0059] Generally, the higher the temperature during curing with active energy rays, the higher the reactivity and the larger the surface unevenness structure, so the cured product has a larger arithmetic mean roughness (Ra), a higher haze, and a lower gloss. Therefore, in order to industrially produce a cured product of a certain quality, it has been necessary to strictly keep the curing temperature constant. However, the curable composition of the present invention has an excellent feature that even if the curing temperature increases, the increase in Ra is slight, or in some cases, Ra does not change or only decreases slightly, so that the cured product can be stably produced as designed.

[0060] (Laminate) The laminate of the present invention has a layer made of a substrate and a layer (uneven layer) made of a cured film of a curable composition. The laminate may further have a primer layer between the substrate and the cured film. In addition, the laminate may have a back functional layer on the surface of the substrate opposite to the cured film side. As long as it does not impair the effects of the present invention, the cured film may have a surface functional layer on the surface opposite to the substrate.

[0061] (Primer layer) The primer layer is appropriately provided between the substrate and the cured film (concave-convex layer) in order to impart various functions. The primer layer may be a single layer having a single or multiple functions, or may be composed of multiple layers.

[0062] In a preferred embodiment, the primer layer is an adhesion improving layer. If the adhesion between the substrate and the uneven layer is insufficient, the laminate may not be usable depending on the application. By having the adhesion improving layer, the adhesion between the substrate and the uneven layer is improved, and the laminate can be used for various applications. From the viewpoint of improving adhesion, it is preferable that the adhesion improving layer contains either one or both of a resin and a compound derived from a crosslinking agent.

[0063] In another preferred embodiment, the primer layer is an antistatic layer. When the primer layer is an antistatic layer, adhesion of dust and the like due to peeling electrification or frictional electrification can be reduced to the outermost surface of the laminate, particularly to the outermost surface on the side where the uneven layer is present relative to the substrate. In order to make the primer layer an antistatic layer, for example, an antistatic agent may be contained in the primer layer.

[0064] The resin contained in the primer layer may be a conventionally known resin. Specific examples of the resin include polyester resin, acrylic resin, urethane resin, polyvinyl resin (polyvinyl alcohol, vinyl chloride-vinyl acetate copolymer, etc.), etc. Among them, polyester resin, acrylic resin, and urethane resin are preferred in terms of adhesion performance and coating properties. When the substrate is a resin film, the resin contained in the primer layer is preferably the same type of resin as that of the resin film from the viewpoint of affinity with the substrate. For example, when the substrate is a polyester film, the primer layer preferably contains a polyester resin. When the substrate is a poly(meth)acrylate film, the primer layer preferably contains an acrylic resin.

[0065] The antistatic agent contained in the primer layer is not particularly limited, and any known antistatic agent can be used. Examples of the antistatic agent include compounds having an ammonium group, polyether compounds, compounds having a sulfonic acid group, betaine compounds, and conductive organic polymers.

[0066] The primer layer may contain particles to improve blocking and slip properties. The primer layer may contain additives such as antifoaming agents, coatability improvers, thickeners, organic lubricants, ultraviolet absorbers, antioxidants, foaming agents, dyes, and pigments, as necessary, within the scope of the present invention.

[0067] The proportion of the resin in 100% by mass of the primer layer is, for example, 5% by mass or more, preferably 10 to 99% by mass, more preferably 20 to 95% by mass, and even more preferably 30 to 90% by mass. If the proportion of the resin is within the above range, the adhesion performance and the appearance of the primer layer are more excellent.

[0068] The thickness of the primer layer depends on the material used in the primer layer and the performance to be achieved, so cannot be generalized, but is preferably in the range of 0.001 to 10 μm, more preferably 0.01 to 4 μm, and even more preferably 0.02 to 1 μm. The primer layer can be formed by a known method.

[0069] (Surface functional layer) The surface functional layer is a layer provided on the surface of the cured film (uneven layer) opposite to the substrate layer to impart various functions. Examples of the surface functional layer include an antifouling layer, an antistatic layer, a refractive index adjustment layer (antireflection layer, low reflection layer, etc.), an infrared absorbing layer, an ultraviolet absorbing layer, and a color correction layer. The surface functional layer may be a single layer having a single or multiple functions, or may be composed of multiple layers.

[0070] The antifouling layer is provided to improve the antifouling performance by imparting water repellency and oil repellency to the cured film. As the material used for the antifouling layer, conventionally known materials such as silicone compounds, fluorine compounds, and long-chain alkyl group-containing compounds can be used. Among these, silicone compounds and fluorine compounds are preferred for exhibiting stronger antifouling performance, and fluorine compounds and long-chain alkyl group-containing compounds are preferred from the viewpoint of not contaminating the other party with which the antifouling layer comes into contact.

[0071] As the antistatic agent used when forming the antistatic layer as the surface functional layer, various conventionally known antistatic agents can be used. In addition, for example, a method of introducing a double bond such as an acryloyl group into a compound having an ammonium group and reacting at the double bond is also preferred.

[0072] Examples of the refractive index adjusting layer include a high refractive index layer, a low refractive index layer, and a laminate thereof.

[0073] The thickness of the surface functional layer is preferably 5 times or less, more preferably 3 times or less, the height from the concave to the convex of the concave-convex structure of the cured film. The smaller this ratio is, the less likely the matte performance of the cured film is to decrease. The thickness of the surface functional layer depends on the height from the concave to the convex of the concave-convex structure of the cured film, so it cannot be generalized, but it is usually in the range of 0.001 to 3 μm, preferably 0.005 to 2 μm, more preferably 0.01 to 1 μm, even more preferably 0.02 to 0.5 μm, and particularly preferably 0.03 to 0.2 μm. By using within the above range, it is possible to achieve both the expression of the function of the surface functional layer and the matte property of the cured film. The surface functional layer can be formed by a known method.

[0074] (Back functional layer) The back functional layer is a layer provided on the surface opposite to the cured film (uneven layer) of the base layer to impart various functions. Examples of the back functional layer include an adhesive layer, an antistatic layer, a refractive index adjustment layer, and an antiblocking layer. The back functional layer may be a single layer having a single or multiple functions, or may be composed of multiple layers. The adhesive layer is provided to bond the laminate to various adherends. The antistatic layer is provided to prevent adhesion of dust and the like due to peeling charge or frictional charge on the outermost surface of the laminate, particularly on the outermost surface opposite to the uneven layer side of the base layer, and to prevent defects and the like caused thereby. The refractive index adjustment layer is provided, for example, to improve the total light transmittance of the laminate. The antiblocking layer is provided to reduce blocking of the laminate.

[0075] Examples of the adhesive for forming the adhesive layer include known adhesives such as acrylic, polyester, urethane and rubber adhesives. Among these, acrylic adhesives are preferred in view of versatility. The components forming the antistatic layer and the refractive index adjusting layer are the same as those explained for the surface functional layer.

[0076] The thickness of the back functional layer depends on the material used in the back functional layer and the performance to be achieved, so it cannot be generally stated, but is, for example, 0.001 to 30 μm. When the back functional layer is an adhesive layer, the thickness is preferably 0.01 to 30 μm, more preferably 0.1 to 20 μm. When the back functional layer is an antistatic layer, the thickness is preferably 0.001 to 10 μm, more preferably 0.01 to 5 μm. The back surface functional layer can be formed by a known method.

[0077] (Formation of surface functional layer and back functional layer) The front surface functional layer and the back surface functional layer can be formed, for example, by coating a liquid prepared by dispersing the above-mentioned components in a solution or solvent so that the solid content is approximately 0.1 to 80% by mass onto a specified surface, followed by drying and curing.

[0078] Examples of the coating method include conventionally known coating methods such as gravure coating, reverse roll coating, die coating, air doctor coating, blade coating, rod coating, bar coating, curtain coating, knife coating, transfer roll coating, squeeze coating, impregnation coating, kiss coating, spray coating, calendar coating, and extrusion coating.

[0079] The drying and curing conditions when forming the front functional layer and the back functional layer are not particularly limited, but the drying temperature of the solvent such as water used in the coating liquid is usually in the range of 50 to 150°C, preferably 80 to 130°C, and more preferably 90 to 120°C. The drying time is generally in the range of 3 to 200 seconds, preferably 5 to 120 seconds. In addition, in order to improve the strength of the front functional layer and the back functional layer, it is preferable to perform a heat treatment after drying at a temperature of usually 150 to 270°C, preferably 170 to 230°C, and more preferably 180 to 210°C. The heat treatment time is generally in the range of 3 to 200 seconds, and preferably 5 to 120 seconds. Such a heat treatment is suitable when the laminate is a film.

[0080] The cured product having a concave-convex structure obtained by the present invention can be used for building materials, interior decoration of vehicles, glass decoration, and for improving the design of housings for electric and electronic devices by utilizing its matte property. In addition, the iridescent property, which changes color depending on the observation angle, can be used for anti-counterfeiting cards and design articles. EXAMPLES

[0081] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these. The measurement and evaluation methods used in the present invention are as follows.

[0082] <Weight average molecular weight> The weight average molecular weight of the polymer (A) can be measured under the following measurement conditions. (GPC measurement conditions) Columns: "TSK-gel superHZM-M", "TSK-gel HZMM", "TSK-gel HZ2000" Eluent:THF Flow rate: 0.35mL / min Injection volume: 10μL Column temperature: 40℃ Detector: UV-8020

[0083] <Arithmetic mean roughness (Ra) of surface unevenness> The arithmetic mean roughness (Ra) of the surface unevenness structure of the cured product was measured using a surface shape measurement system (Hitachi High-Tech Science Corporation's scanning white light interference microscope "VS1330"). The magnification of the objective lens during measurement was set to 20x. The surface unevenness structure in an area of ​​236.87μm x 177.60μm on the uneven layer surface was measured using optical interference, and interpolation and baseline correction were performed to calculate the arithmetic mean roughness Ra of the uneven cross section.

[0084] <Total light transmittance / haze> The laminate in which the cured film was formed on the substrate was used as the measurement subject. The total light transmittance and haze were measured using a Nippon Denshoku Industries haze meter "SH7000" in accordance with JIS Z8722:2009 (geometric conditions of irradiation and reception of a transmitting object), JIS K7361-1:1997 (test method for total light transmittance of plastic transparent materials), and JIS K7136:2000 (method of determining haze of plastic transparent materials). Regarding the haze, the haze of only the substrate was measured and subtracted from the measured haze value of the laminate to evaluate the haze of only the uneven layer (cured film).

[0085] <20° and 60° gloss> The laminate having a cured film formed on a substrate was used as the measurement subject. The 20° and 60° gloss (20° and 60° specular gloss) were measured using a gloss meter "VG2000" manufactured by Nippon Denshoku Industries Co., Ltd. in accordance with JIS Z 8741-1997. The lower the gloss value, the better the matte property.

[0086] <Temperature dependence> To calculate the slope (μm / ℃) at a temperature of 60℃ when plotting a graph with temperature (℃) on the horizontal axis and Ra (μm) on the vertical axis, the slope of the line passing through two points, Ra when cured at a low temperature below 60℃ (58-59℃) and Ra when cured at a high temperature above 60℃ (65-71℃), was calculated, and the temperature dependency during curing was evaluated according to the following criteria. ○: Tilt is 0.02μm / ℃ or less ×: The slope is greater than 0.02 μm / °C.

[0087] (Synthesis Example 1: Synthesis of Monomer (i-1)) Methacrylic anhydride (Tokyo Chemical Industry Co., Ltd.) was distilled under reduced pressure, and the fraction with a purity of 99.8% or more was collected to obtain a distillate of methacrylic anhydride. The reduced pressure distillation was carried out by gradually increasing the temperature from room temperature to 90°C at a pressure of 30 Pa. Separately, 22.4 g (0.1 mol) of 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one (manufactured by Tokyo Chemical Industry Co., Ltd.) and 30.4 g (0.3 mol) of triethylamine (manufactured by Tokyo Chemical Industry Co., Ltd.) were dissolved in 500 mL of methylene chloride (manufactured by Tokyo Chemical Industry Co., Ltd.) to which 23.1 g (0.15 mol) of the above-mentioned distillate of methacrylic anhydride was added dropwise at room temperature and stirred for 12 hours. The reaction solution was washed three times with 500 mL of ion-exchanged water, and then the organic phase was concentrated to remove the solvent. The residue was purified by column chromatography (ethyl acetate / hexane = 10 / 90 (volume ratio)) to obtain 21.6 g of the target compound (yield 74%). 1 H-NMR analysis confirmed that the compound obtained was 2-[4-(2-hydroxy-2-methyl-1-oxopropyl)phenoxy]ethyl methacrylate. 1 H NMR (300MHz, chloroform-d): δ8.06(d,J=9.0Hz,2H),6.96(d,J=9.0Hz,2H),6.13(d,J=0.6Hz,1H),5.5 9(s,1H),4.50(d,J=5.1Hz,2H),4.29(dd,J=5.5,4.1Hz,3H),1.94(dd,J=1.6,1.0Hz,3H),1.61(s,6H).

[0088] (Synthesis Example 2: Synthesis of Polymer A-1) In a flask equipped with a stirrer, a cooling tube and a thermometer, 78.0 parts of methyl isobutyl ketone (hereinafter referred to as MIBK) were placed and stirred. Next, the inside of the flask was replaced with nitrogen and heated to 65°C, and a mixed solution of 10.0 parts of stearyl methacrylate (manufactured by Mitsubishi Chemical Corporation, trade name: Acrylate (registered trademark) S), 10.0 parts of N,N-diethylaminoethyl methacrylate (manufactured by Mitsubishi Chemical Corporation, trade name: Acrylate DE), 30.0 parts of 3,3,5-trimethylcyclohexyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., trade name: Viscoat (registered trademark) #196), 25.0 parts of 4-methacryloyloxybenzophenone (manufactured by MCC Unitech Co., Ltd.), 25.0 parts of the monomer (i-1) obtained in Synthesis Example 1, 1.0 part of azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd., trade name: V-65), and 78.0 parts of MIBK was added dropwise over 2 hours. After another 2 hours, in order to increase the polymerization rate, a mixture of 0.5 parts of azobis(2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd., product name: V-65) and 0.6 parts of MIBK was added and held for 5 hours. Thereafter, the reaction solution was cooled to 40°C to polymerize a polymer (A)-1 (hereinafter referred to as A-1) having an active group that generates radicals when irradiated with active energy rays. The non-volatile content of A-1 was 40%, and the weight average molecular weight (Mw) was 16700. The composition and evaluation results are shown in Table 1.

[0089] (Synthesis Example 3: Synthesis of Polymer A-2) Polymerization was carried out under the same conditions as in A-1, except that 30.0 parts of 3,3,5-trimethylcyclohexyl acrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., product name: Viscoat #196) was replaced with 30.0 parts of 2-ethylhexyl methacrylate (manufactured by Mitsubishi Chemical Corporation, product name: Acryester EH). The composition and evaluation results are shown in Table 1.

[0090] [Table 1]

[0091] [Example 1] In a flask equipped with a stirrer, 7.0 parts by mass of A-1 as a polymer (A) having an active group that generates radicals upon irradiation with active energy rays was added as a nonvolatile content, 14.0 parts by mass of trimethylolpropane trimethacrylate (manufactured by Mitsubishi Chemical Corporation, product name: Acrylic Ester TMP, abbreviated as B-1 in the table) as a polyfunctional methacrylate (B) as a nonvolatile content, 79.0 parts by mass of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., product name: KAYARAD (registered trademark) DPHA, abbreviated as C-1 in the table) as a polyfunctional acrylate (C) as a nonvolatile content, 97.7 parts by mass of propylene glycol monomethyl ether (hereinafter referred to as PGM), 41.8 parts by mass of methyl ethyl ketone (hereinafter referred to as MEK), and 10.5 parts by mass of methyl isobutyl ketone (hereinafter referred to as MIBK) as an organic solvent (D) were added, and the mixture was stirred until uniform, to prepare a curable composition.

[0092] The obtained curable composition was applied to a 40 μm thick TAC film (TG40UL, manufactured by Fujifilm Corporation) using a #8 bar coater, and the obtained coating film was dried for 60 seconds in a hot air dryer heated to 70° C. to volatilize the solvent. Next, the coating film was cured in air using a high-pressure mercury lamp using a UV conveyor manufactured by Toshiba Lighting & Technology Corporation to prepare an evaluation sample. The curing was performed when the integrated light amount at wavelengths of 300 to 390 nm was 300 mJ / cm when measured using an illuminometer manufactured by Iwasaki Electric Co., Ltd. (Eye ultraviolet integrated illuminometer "UVPF-A1, PD-365"). 2 (150mW / cm 2 ), and irradiate for about 2 seconds twice (600 mJ / cm 2 )went. A thermocouple was fixed to the film surface to measure the temperature of the coating during curing, and the amount of heat exhausted from the UV conveyor was adjusted to create a difference of 5°C or more between the high and low temperatures. The curable composition was cured under each temperature condition, producing a laminate in which a cured film of the curable composition was laminated on the TAC film. The evaluation results of the obtained cured product are shown in Table 2.

[0093] [Example 2] A curable composition was prepared in the same manner as in Example 1, except that 9.0 parts by mass of trimethylolpropane trimethacrylate (manufactured by Mitsubishi Chemical Corporation, trade name: Acrylic Ester TMP) was added as the multifunctional methacrylate (B) in terms of non-volatile content, and 84.0 parts by mass of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., trade name: KAYARAD DPHA) was added as the multifunctional acrylate (C) in a flask equipped with a stirrer, and a laminate was produced. The evaluation results of the obtained cured product are shown in Table 2.

[0094] [Example 3] A curable composition was prepared in the same manner as in Example 1, except that A-2 was used as the polymer (A) having an active group that generates radicals upon irradiation with active energy rays in a flask equipped with a stirrer, in an amount of 7.0 parts by mass as the polymer nonvolatile content, and a laminate was produced. The evaluation results of the cured product of the obtained coating liquid are shown in Table 2.

[0095] [Comparative Example 1] A curable composition was prepared in the same manner as in Example 1, except that 9.0 parts by mass of trimethylolpropane triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name: NK Ester A-TMPT) was added as the polyfunctional acrylate (C) in a flask equipped with a stirrer, as a non-volatile content, and 84.0 parts by mass of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., product name: KAYARAD DPHA) was added as a non-volatile content, and a laminate was produced. The evaluation results of the cured product of the obtained coating liquid are shown in Table 2.

[0096] [Comparative Example 2] A coating solution of the curable composition was prepared in the same manner as in Example 1, except that 28.0 parts by mass of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (manufactured by Osaka Organic Chemical Industry Co., Ltd., product name: Viscoat #300, abbreviated as C-2 in the table) as the nonvolatile content and 65.0 parts by mass of dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., product name: KAYARAD DPHA) as the nonvolatile content were added to a flask equipped with a stirrer, and a laminate was produced. The evaluation results of the cured product of the obtained coating solution are shown in Table 2.

[0097] [Table 2]

[0098] The curable compositions of Examples 1 to 3 containing the polymer (A) and the methacrylate (B) had a small temperature dependency during curing, whereas the curable compositions of Comparative Examples 1 and 2 not containing the methacrylate (B) had a large temperature dependency during curing.

Claims

1. a polymer (A) having an active group that generates radicals upon irradiation with active energy rays; Methacrylate (B), An acrylate (C); Including, The polymer (A) contains a structural unit derived from a (meth)acrylic acid ester having an active group, The curable composition, wherein the methacrylate (B) contains a di- or higher-functional methacrylate.

2. The curable composition according to claim 1, wherein the active group that generates radicals upon irradiation with active energy rays is at least one selected from the group consisting of a benzophenone group, an acetophenone group, a benzoin group, an α-hydroxyketone group, an α-aminoketone group, an α-diketone group, an α-diketone dialkyl acetal group, an anthraquinone group, a thioxanthone group, and a phosphine oxide group.

3. The curable composition according to claim 1 or 2, wherein the polymer (A) contains a structural unit derived from an alkyl (meth)acrylate ester having an alkyl group having 4 or more carbon atoms.

4. The curable composition according to any one of claims 1 to 3, wherein the polymer (A) has a structural unit derived from a (meth)acrylic acid ester having a hydrogen donor functional group.

5. The curable composition according to any one of claims 1 to 4, wherein the polymer (A) has a weight average molecular weight of 1,000 to 500,000.

6. The curable composition according to any one of claims 1 to 5, further comprising an organic solvent (D).

7. A cured product obtained by curing the curable composition according to any one of claims 1 to 6.

8. The cured product according to claim 7 , which is a film-like product having an uneven structure on its surface.

9. A laminate comprising the cured product according to claim 7 or 8 laminated on a surface of a substrate.

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