Curable composition, polarizer protective film, and polarizing plate

Abstract

To provide a curable composition whereby, in a laminate such as a polarizer protective film having a hard coat layer on a substrate of any type, it is possible to improve adhesion to the substrate while generally keeping the antiglare properties of the hard coat layer; a polarizer protective film that is a laminate with a hard coat layer being a cured product of the curable composition formed on a substrate film; and a polarizing plate having the polarizer protective film bonded to a polarizer.SOLUTION: A curable composition contains a methacrylate (M) having three or more radical-polymerizable double bonds, an acrylic polymer (P1) having a hydroxy group, and an acrylic polymer (P2) different from (P1).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a curable composition for forming a hard coating layer that imparts scratch resistance to the surface of a plastic substrate, a cured product thereof, a laminate having a hard coating layer made of the cured product on the surface of a substrate film, a polarizer protective film made of the laminate, and a polarizing plate obtained by bonding the polarizer protective film to a polarizer. [Background technology]

[0002] Polarizing plates used in liquid crystal displays and the like have a polarizer with a polarizer protective film laminated on it. Conventionally, triacetyl cellulose (hereinafter referred to as TAC) film has been used as the polarizer protective film. Since TAC film generally has low surface hardness, a hard coat layer is laminated on the surface to prevent scratches.

[0003] In recent years, as liquid crystal display devices have become larger and thinner, the use of various plastic films, such as acrylic polymers, which have higher moisture-proofing properties than TAC, polyethylene terephthalate (hereinafter referred to as PET), cyclic olefin polymers (hereinafter referred to as COP), and cyclic olefin copolymers (hereinafter referred to as COC), as polarizer protective films has been considered.

[0004] Furthermore, in electronic devices having liquid crystal display devices, such as mobile phones and smartphones, with the progress of diversifying designs, thinning, and increasing screen size, there is an increasing demand for the covers of the liquid crystal display devices themselves to be thinner, lighter, less expensive, etc. Glass substrates are generally used for such display covers, but with the demand for thinner, lighter, less expensive, etc. display covers themselves, the use of various plastic sheets, similar to the polarizer protective film described above, is currently being considered.

[0005] Such polarizer protective films and display covers also require a hard coating layer on their surfaces to prevent scratches. Some hard coating layers tend to reflect external light, which reduces the visibility of liquid crystal display devices. Therefore, particles that impart antiglare properties are sometimes blended into the hard coating agent. For example, Patent Document 1 describes an antiglare laminate film in which a cured product of a curable composition containing urethane acrylate, polyol (meth)acrylate, and a (meth)acrylic polymer having an alkyl group containing two or more hydroxyl groups is laminated on the surface of a triacetyl cellulose resin film, and a polarizing plate in which the laminate film is laminated on a polarizer. Furthermore, Patent Documents 2 and 3 describe an antiglare laminate film in which a cured product of a curable composition containing a (meth)acrylate having a hydroxyl group in the molecule and a (meth)acrylate not having a hydroxyl group in the molecule is laminated on the surface of a resin film, and a polarizing plate in which the laminate film is laminated on a polarizer. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-047722 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-081118 [Patent Document 3] International Publication No. 2010 / 035761 Summary of the Invention [Problem to be solved by the invention]

[0007] However, there is a concern that the layers formed from the cured products of the curable compositions described in Patent Documents 1 to 3 may have a problem with adhesion depending on the material of the substrate. The present invention aims to provide a curable composition that can improve adhesion to a substrate while largely maintaining the antiglare properties of the hard coat layer in laminates such as polarizer protective films having a hard coat layer on the surface of various substrates; a polarizer protective film consisting of a laminate having a hard coat layer made of a cured product of this curable composition on the surface of a substrate film; and a polarizing plate obtained by bonding this polarizer protective film to a polarizer. [Means for solving the problem]

[0008] The above-mentioned problems are solved by the present invention. The gist of the present invention is as follows [1] to

[15] . [1] A curable composition comprising a (meth)acrylate (M) having three or more radically polymerizable double bonds, an acrylic polymer (P1) having a hydroxyl group, and an acrylic polymer (P2) different from (P1). [2] The curable composition according to [1], further comprising a photopolymerization initiator (I). [3] The curable composition according to [1] or [2], wherein the (meth)acrylate (M) has 4 or more and 15 or less radically polymerizable double bonds. [4] The curable composition according to any one of [1] to [3], wherein the acrylic polymer (P1) has a hydroxyl value of 10 mgKOH / g or more. [5] The curable composition according to any one of [1] to [4], wherein the acrylic polymer (P2) has a weight average molecular weight of 1,000 or more and 100,000 or less. [6] The curable composition according to any one of [1] to [5], wherein the acrylic polymer (P2) is a polymer having 30% or more by mass of structural units derived from methyl methacrylate. [7] The curable composition according to any one of [1] to [6], further comprising particles (G) that impart antiglare properties. [8] The curable composition according to any one of [1] to [7], wherein the particles (G) that impart antiglare properties are organic particles. [9] The curable composition according to any one of [1] to [8], further comprising inorganic fine particles (S).

[10] A cured product comprising the curable composition according to any one of [1] to [9].

[11] A laminate having a substrate layer and a layer made of the cured product according to

[10] .

[12] The laminate according to

[11] , wherein the substrate layer contains at least one selected from the group consisting of triacetyl cellulose, (meth)acrylic, polyethylene terephthalate, and cyclic polyolefin.

[13] The laminate according to

[11] or

[12] , which has a surface functional layer on the cured product.

[14] A polarizer protective film comprising the laminate according to

[13] .

[15] A polarizing plate obtained by laminating the surface of the polarizer protective film according to

[14] that does not have a hard coat layer to a polarizer. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a curable composition that can improve adhesion to a substrate while generally maintaining the antiglare properties of the hard coat layer in laminates such as polarizer protective films having a hard coat layer on the surface of various substrates, a cured product thereof, a laminate having a hard coat layer made of the cured product on the surface of a substrate film, a polarizer protective film made of the laminate, and a polarizing plate obtained by bonding the polarizer protective film to a polarizer. DETAILED DESCRIPTION OF THE INVENTION

[0010] In the present invention, when the expression "(meth)acrylate" is used, it means one or both of "acrylate" and "methacrylate". When the expression "(meth)acryloyl" is used, it means one or both of "acryloyl" and "methacryloyl". When the expression "(meth)acrylic" is used, it means one or both of "acrylic" and "methacrylic".

[0011] The present invention relates to a curable composition (hereinafter also referred to as the composition of the present invention) containing a (meth)acrylate (M) having three or more radically polymerizable double bonds, an acrylic polymer (P1), and an acrylic polymer (P2) different from (P1).

[0012] The composition of the present invention can be used to form a cured layer that has good adhesion to various substrates. This cured layer also has good scratch resistance, making it suitable as a hard coat layer.

[0013] [(Meth)acrylate (M)] The (meth)acrylate (M) having three or more radically polymerizable double bonds that constitutes the composition of the present invention contributes to the curability of the curable composition.

[0014] Examples of the (meth)acrylate (M) include trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris-2-hydroxyethyl isocyanurate tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and ditrimethylolpropane hexa(meth)acrylate. Examples of the polyfunctional (meth)acrylate include tri- or higher functional polyfunctional (meth)acrylates such as (meth)acrylates; modified polyfunctional (meth)acrylate compounds in which part of these tri- or higher functional polyfunctional (meth)acrylates is substituted with an alkyl group or ε-caprolactone; polyfunctional (meth)acrylates having a nitrogen atom-containing heterocyclic structure such as an isocyanurate structure; polyfunctional (meth)acrylates having a multi-branched resinous structure such as polyfunctional (meth)acrylates having a dendrimer structure and polyfunctional (meth)acrylates having a hyperbranched structure; and urethane (meth)acrylates in which a (meth)acrylate having a hydroxyl group, such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, or dipentaerythritol penta(meth)acrylate, is added to an isocyanate, triisocyanate, or isocyanurate. Among these, compounds containing a hydroxyl group are preferred in order to improve antiglare properties, and examples thereof include pentaerythritol triacrylate and dipentaerythritol pentaacrylate.Furthermore, in terms of compatibility with the acrylic polymer (P), pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferred, and in terms of the curability of the curable composition, dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate are more preferred.

[0015] The number of radically polymerizable double bonds in the (meth)acrylate (M) is preferably 4 or more and 15 or less, more preferably 5 or more and 10 or less, from the viewpoint of the curability of the curable composition.

[0016] The composition of the present invention may contain monofunctional or bifunctional (meth)acrylates other than the (meth)acrylate (M) in order to adjust the appearance of the cured layer and the viscosity of the composition liquid.

[0017] Examples of monofunctional (meth)acrylates include alkyl (meth)acrylates such as methyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, and isobornyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, methoxypropyl (meth)acrylate, and ethoxypropyl (meth)acrylate; acrylate and other alkoxyalkyl (meth)acrylates; aromatic (meth)acrylates such as benzyl (meth)acrylate and phenoxyethyl (meth)acrylate; amino group-containing (meth)acrylates such as diaminoethyl (meth)acrylate and diethylaminoethyl (meth)acrylate; ethylene oxide-modified (meth)acrylates such as methoxyethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate and phenylphenol ethylene oxide-modified (meth)acrylate; and heterocycle-containing (meth)acrylates such as glycidyl (meth)acrylate and tetrahydrofurfuryl (meth)acrylate.

[0018] Examples of bifunctional (meth)acrylates include alkanediol di(meth)acrylates such as 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, and tricyclodecanedimethylol di(meth)acrylate; bisphenol-modified di(meth)acrylates such as bisphenol A ethylene oxide-modified di(meth)acrylate and bisphenol F ethylene oxide-modified di(meth)acrylate; polyalkylene glycol di(meth)acrylates such as polyethylene glycol di(meth)acrylate and polypropylene glycol di(meth)acrylate; urethane di(meth)acrylate; and epoxy di(meth)acrylate.

[0019] [Acrylic polymer (P1)] The hydroxyl group-containing acrylic polymer (P1) constituting the composition of the present invention contributes to the cohesion of the particles contained in the cured product layer that impart antiglare properties and to the adhesion to various substrates.

[0020] The acrylic polymer (P1) is a compound having a hydroxyl group of an acrylic polymer. Methods for introducing the hydroxyl group include, for example, a method of generating a hydroxyl group by reacting an acrylic polymer having an epoxy group with a compound having a carboxyl group (Method 1), a method of generating a hydroxyl group by reacting an acrylic polymer having a carboxyl group with a compound having an epoxy group (Method 2), a method of generating a hydroxyl group by hydrolysis of an acrylic polymer having an ester group (Method 3), a method of reacting an acrylic polymer having a carboxyl group with a compound having two or more hydroxyl groups (Method 4), and a method of obtaining the hydroxyl group by polymerizing a (meth)acrylic acid alkyl ester having a hydroxyl group (Method 5). The above methods may be used in combination. In the following, a radically polymerizable monomer having a hydroxyl group may be referred to as a vinyl monomer.

[0021] In the above-mentioned method 1, examples of the vinyl monomer having an epoxy group used to obtain an acrylic polymer having an epoxy group include glycidyl (meth)acrylate, 3,4-epoxycyclohexyl (meth)acrylate, and 3,4-epoxycyclohexylmethyl (meth)acrylate. Among these, glycidyl (meth)acrylate is preferred, and glycidyl methacrylate is particularly preferred, in consideration of good reactivity and ease of use of the material. These may be used alone or in combination of two or more.

[0022] In addition, from the viewpoint of curability, the compound having a carboxyl group in Method 1 preferably also has a double bond. Examples of compounds having a double bond and a carboxyl group include (meth)acrylic acid, carboxyethyl (meth)acrylate, an adduct of glycerin di(meth)acrylate and succinic anhydride, an adduct of pentaerythritol tri(meth)acrylate and succinic anhydride, and an adduct of pentaerythritol tri(meth)acrylate and phthalic anhydride. Among these, (meth)acrylic acid and an adduct of pentaerythritol tri(meth)acrylate and succinic anhydride are preferred, (meth)acrylic acid is more preferred, and acrylic acid is particularly preferred in consideration of reactivity during hard coat layer formation. Note that the compound having a double bond and a carboxyl group may be used alone or in combination of two or more.

[0023] In the method 2, examples of the vinyl monomer having a carboxyl group used to obtain an acrylic polymer having a carboxyl group include (meth)acrylic acid, carboxyethyl (meth)acrylate, and polybasic acid-modified (meth)acrylate. Among these, (meth)acrylic acid is preferred. These may be used alone or in combination of two or more.

[0024] In addition, from the viewpoint of curability, the compound having an epoxy group in Method 2 preferably also has a double bond. Examples of compounds having a double bond and an epoxy group include glycidyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate glycidyl ether. Among these, glycidyl (meth)acrylate is preferred. These may be used alone or in combination of two or more.

[0025] In the method 3, examples of the vinyl monomer having an ester group used to obtain an acrylic polymer having an ester group include vinyl acetate, allyl acetate, etc. These may be used alone or in combination of two or more.

[0026] In the above-mentioned method 3, an aqueous solution of sodium hydroxide, an aqueous solution of potassium hydroxide, or the like can be used for hydrolysis of the acrylic polymer having an ester group.

[0027] In the method 4, the same acrylic polymer having a carboxyl group as in the method 2 can be used.

[0028] In the method 4, examples of the compound having two or more hydroxyl groups include 2,3-dihydroxypropyl(meth)acrylate.

[0029] In the method 5, examples of the vinyl monomer used as the (meth)acrylic acid alkyl ester having a hydroxyl group include hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, and 2,3-dihydroxypropyl (meth)acrylate.

[0030] Among the above methods, Method 1 is preferred because the reaction is easy to control and the product is easy to handle. In Method 1, the hydroxyl group is introduced by a ring-opening addition reaction between the epoxy group of the acrylic polymer having an epoxy group and the carboxyl group of the compound having a carboxyl group.

[0031] In the method 1, the amount of the epoxy group-containing monomer in the epoxy group-containing acrylic polymer is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, and particularly preferably 50% by mass or more, based on the total amount of monomers constituting the epoxy group-containing acrylic polymer. There is no particular upper limit, but the amount is preferably 99.9% by mass or less. By using the amount in this range, it is possible to achieve improved antiglare properties and improved adhesion to the substrate.

[0032] In the method 1, the ratio of the compound having a carboxyl group to the epoxy groups in the acrylic polymer having an epoxy group is preferably 10 mol % or more and 150 mol % or less, more preferably 30 mol % or more and 130 mol % or less, and even more preferably 50 mol % or more and 110 mol % or less. Using the compound within this range is preferable from the viewpoint of introducing a sufficient amount of hydroxyl groups into the acrylic polymer having an epoxy group and also from the viewpoint of reducing the residue of the raw material.

[0033] Furthermore, the acrylic polymer, such as the above-mentioned acrylic polymer having an epoxy group, may be a copolymer of (meth)acrylates other than those mentioned above or other vinyl monomers. The polymerization reaction of these raw materials is usually radical polymerization, and can be carried out under conventionally known conditions.

[0034] Monomers that can be used in combination as raw materials include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, cyclohexyl (meth)acrylate, phenyl (meth)acrylate, methoxy(poly)ethylene glycol (meth)acrylate, methoxy(poly)propylene glycol (meth)acrylate, methoxy(poly)ethylene glycol (poly)propylene glycol (meth)acrylate, octoxy(poly)ethylene glycol (meth)acrylate, octoxy(poly)propylene glycol (meth)acrylate, (meth)acrylates such as octoxytetramethylene glycol (meth)acrylate, lauroxy(poly)ethylene glycol (meth)acrylate, and stearoxy(poly)ethylene glycol (meth)acrylate; acrylamides such as ethyl(meth)acrylamide, n-butyl(meth)acrylamide, i-butyl(meth)acrylamide, t-butyl(meth)acrylamide, N-hydroxyethyl(meth)acrylamide, N-hydroxypropyl(meth)acrylamide, and N,N-dihydroxyethyl(meth)acrylamide; and styrene-based monomers such as styrene, p-chlorostyrene, and p-bromostyrene. These may be used alone or in combination of two or more.

[0035] The acrylic polymer can be produced by radical polymerization using the above-mentioned vinyl monomer as the raw material. The radical polymerization reaction is preferably carried out in an organic solvent in the presence of a radical polymerization initiator.

[0036] Examples of organic solvents used in radical polymerization include ketone solvents such as acetone and methyl ethyl ketone (MEK); alcohol solvents such as ethanol, methanol, isopropyl alcohol (IPA), and isobutanol; ether solvents such as ethylene glycol dimethyl ether and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, propylene glycol monomethyl ether acetate, and 2-ethoxyethyl acetate; and aromatic hydrocarbon solvents such as toluene. These organic solvents may be used alone or in combination of two or more.

[0037] Examples of radical polymerization initiators used in radical polymerization include organic peroxides such as benzoyl peroxide and di-t-butyl peroxide; and azo compounds such as 2,2'-azobisbutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile). These radical polymerization initiators may be used alone or in combination of two or more. The radical polymerization initiator is preferably used in an amount of 0.01% by mass or more and 5% by mass or less relative to 100% by mass of the total of the vinyl monomers used as raw materials.

[0038] In addition, during radical polymerization, a chain transfer agent can be used for the purpose of controlling the weight average molecular weight of the acrylic polymer, etc. Examples of the chain transfer agent include butanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, octyl 2-mercaptopropionate, octyl 3-mercaptopropionate, 2-ethylhexyl mercaptopropionate, 2-ethylhexyl thioglycolate, butyl-3-mercaptopropionate, mercaptopropyltrimethoxysilane, methyl-3-mercaptopropionate, 2,2-(ethylenediaminetetraacetic acid)-2-methylpropanol, methyl-3-mercaptopropionate ... Examples of the thiol-based compounds include (oxy)diethanethiol, ethanethiol, 4-methylbenzenethiol, octanoic acid 2-mercaptoethyl ester, 1,8-dimercapto-3,6-dioxaoctane, decantrithiol, dodecyl mercaptan, diphenyl sulfoxide, dibenzyl sulfide, 2,3-dimethylcapto-1-propanol, mercaptoethanol, thiosalicylic acid, thioglycerol, thioglycolic acid, 3-mercaptopropionic acid, thiomalic acid, mercaptoacetic acid, mercaptosuccinic acid, and 2-mercaptoethanesulfonic acid. These may be used alone or in combination of two or more.

[0039] The amount of the chain transfer agent used is preferably 0.1% by mass to 25% by mass, more preferably 0.5% by mass to 20% by mass, and even more preferably 1.0% by mass to 15% by mass, based on 100% by mass of the total of the raw vinyl monomers.

[0040] The reaction time for radical polymerization is preferably from 1 to 20 hours, more preferably from 3 to 12 hours, and the reaction temperature is preferably from 40 to 120°C, more preferably from 50 to 100°C.

[0041] To react a carboxyl group-containing compound with an acrylic polymer, the carboxyl group-containing compound is added to the acrylic polymer obtained as described above and reacted in the presence of one or more catalysts, such as triphenylphosphine, tetrabutylammonium bromide, tetramethylammonium chloride, or triethylamine, typically at a temperature of 90°C to 140°C, preferably 100°C to 120°C, for typically 3 to 9 hours. The catalyst is preferably used in an amount of 0.5 to 3% by mass relative to 100% by mass of the combined raw materials (meth)acrylic acid ester polymer and the carboxyl group-containing compound. This reaction may be carried out immediately after the acrylic polymer is produced by polymerization, or may be carried out by first separating the acrylic polymer from the reaction system and then adding the carboxyl group-containing compound.

[0042] The hydroxyl value of the acrylic polymer (P1) is preferably 10 mgKOH / g or more, more preferably 30 mgKOH / g or more and 400 mgKOH / g or less, even more preferably 50 mgKOH / g or more and 300 mgKOH / g or less, and particularly preferably 70 mgKOH / g or more and 250 mgKOH / g or less. By using it in this range, the antiglare properties of the cured product layer are improved and the adhesion to various substrates is good.

[0043] The weight average molecular weight of the acrylic polymer (P1) is preferably from 1,000 to 100,000, more preferably from 3,000 to 80,000, even more preferably from 5,000 to 60,000, and particularly preferably from 7,000 to 50,000. By using it within this range, the surface hardness and smoothness of the cured product layer can be ensured.

[0044] The glass transition temperature (Tg) of the acrylic polymer (P1) is preferably from 0° C. to 120° C., more preferably from 5° C. to 110° C., even more preferably from 10° C. to 100° C., and particularly preferably from 15° C. to 95° C. By using the acrylic polymer (P1) within this range, the surface hardness and smoothness of the cured product layer can be ensured. The glass transition temperature (Tg) can be calculated from the type and mass fraction of the monomer units constituting the acrylic polymer (P1) by the following Fox formula. 1 / Tg=Σ(Wi / Tgi) In this formula, Tg is the glass transition temperature (unit: K) of the acrylic polymer (P1), Wi is the mass fraction of the monomer units derived from monomer i constituting the acrylic polymer (P1), and Tgi is the glass transition temperature (unit: K) of the homopolymer of monomer i. The value of Tgi can be the value described in POLYMER HANDBOOK Volume 1 (WILEY-INTERSCIENCE).

[0045] [Acrylic polymer (P2)] The acrylic polymer (P2) different from (P1) that constitutes the composition of the present invention contributes to improving the adhesion between the cured product layer and various substrates.

[0046] The acrylic polymer (P2) is a polymer whose main structural unit is a (meth)acrylic acid alkyl ester, and is a polymer other than the acrylic polymer (P1) having a hydroxyl group. Examples of the (meth)acrylic acid alkyl ester include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, n-pentyl (meth)acrylate, and n-hexyl (meth)acrylate. These may be used alone or in combination of two or more. Among these, methyl (meth)acrylate is preferred from the viewpoints of the compatibility of the acrylic polymer (P2) with the (meth)acrylate (M) and the heat resistance of the hard coat layer.

[0047] The proportion of structural units derived from alkyl (meth)acrylate, particularly methyl methacrylate, constituting the acrylic polymer (P2) is preferably 30% or more by mass, more preferably 50% or more, even more preferably 70% or more, and particularly preferably 80% or more and 99.9% or less. By using within this range, the surface hardness and adhesion of the cured product layer are improved.

[0048] The weight-average molecular weight of the acrylic polymer (P2) is preferably from 1,000 to 100,000, more preferably from 2,000 to 80,000, even more preferably from 3,000 to 50,000, and particularly preferably from 5,000 to 20,000. By using it within this range, the smoothness and adhesion of the cured product layer are improved.

[0049] The glass transition temperature (Tg) of the acrylic polymer (P2) is preferably 0°C or higher and 150°C or lower, more preferably 20°C or higher and 130°C or lower, even more preferably 40°C or higher and 110°C or lower, and particularly preferably 50°C or higher and 100°C or lower. By using it within this range, the mechanical properties of the cured product layer are improved, and the processability of the laminate obtained by laminating the cured product layers is also improved. The glass transition temperature (Tg) can be calculated by the Fox formula as in the case of the acrylic polymer (P1).

[0050] Examples of methods for producing the acrylic polymer (P2) include solution polymerization, suspension polymerization, and emulsion polymerization. The weight-average molecular weight of the acrylic polymer (P2) can be adjusted by the polymerization initiator, chain transfer agent, solids concentration, reaction conditions, etc.

[0051] The composition of the present invention may contain an organic solvent. In this case, it is preferable to use a particulate acrylic polymer (P2) because it can be easily dissolved in the organic solvent. The particulate acrylic polymer (P2) is preferably produced by suspension polymerization.

[0052] Examples of the method for producing the acrylic polymer (P2) by the suspension polymerization method include a method in which a polymerization initiator is added to an aqueous suspension containing water, a dispersant, and a monomer, and the resulting suspension is heated to carry out polymerization, and then the aqueous suspension containing the particulate acrylic polymer (P2) is filtered, washed, dehydrated, and dried.

[0053] Examples of dispersants used in suspension polymerization include poly(alkali metal (meth)acrylate), copolymers of alkali metal (meth)acrylate and methyl (meth)acrylate, polyvinyl alcohol with a saponification degree of 70% or more and 100% or less, and methyl cellulose. These may be used alone or in combination of two or more.

[0054] The amount of dispersant added in the suspension polymerization method is preferably 0.005% by mass or more and 5% by mass or less, and more preferably 0.01% by mass or more and 1% by mass or less, relative to 100% by mass of all monomers to be polymerized, from the viewpoint of improving dispersion stability in the suspension polymerization and the washability, dewaterability, drying property, and flowability of the resulting particulate polymer.

[0055] In the suspension polymerization method, electrolytes such as sodium carbonate, sodium sulfate, manganese sulfate, etc. may be added to the aqueous suspension for the purpose of improving dispersion stability.

[0056] Examples of polymerization initiators used in suspension polymerization include azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(2-methylbutyronitrile), and 2,2'-azobis(2,4-dimethylvaleronitrile); organic peroxides such as benzoyl peroxide, lauroyl peroxide, t-butylperoxy 2-ethylhexanoate, t-hexylperoxy 2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, and t-hexyl hydroperoxide; and inorganic peroxides such as hydrogen peroxide, sodium persulfate, and ammonium persulfate. These may be used alone or in combination of two or more.

[0057] A chain transfer agent can be used when producing the acrylic polymer (P2). Examples of chain transfer agents include mercaptans such as n-dodecyl mercaptan, thioglycolic acid esters such as octyl thioglycolate, cobalt metal complexes such as bis(boron difluorodiphenyl glyoximate)cobalt(II), α-methylstyrene dimer, and terpinolene. These may be used alone or in combination of two or more. Among these, cobalt metal complexes such as bis(boron difluorodiphenyl glyoximate)cobalt(II) are preferred from the viewpoints of the odor of the composition of the present invention and the weather resistance of the cured product of the composition of the present invention.

[0058] The polymerization temperature when producing the acrylic polymer (P2) is preferably 50° C. or higher and 130° C. or lower, more preferably 60° C. or higher and 100° C. or lower, from the viewpoints of short-term polymerization and polymerization stability.

[0059] [Composition ratio of curable composition] The proportion of the (meth)acrylate (M) in the composition of the present invention is preferably 5% by mass or more and 90% by mass or less, more preferably 10% by mass or more and 80% by mass or less, even more preferably 20% by mass or more and 70% by mass or less, and particularly preferably 30% by mass or more and 60% by mass or less, based on all components excluding the solvent. By using it within this range, good surface hardness can be obtained.

[0060] The proportion of the acrylic polymer (P1) in the composition of the present invention is preferably 2% by mass to 80% by mass, more preferably 3% by mass to 70% by mass, even more preferably 5% by mass to 50% by mass, and particularly preferably 8% by mass to 30% by mass, based on all components excluding the solvent. Using it in this range makes it easier to achieve both antiglare properties and adhesion between the cured product and the substrate.

[0061] The proportion of the acrylic polymer (P2) in the composition of the present invention is preferably 5% by mass to 80% by mass, more preferably 10% by mass to 70% by mass, even more preferably 15% by mass to 60% by mass, and particularly preferably 20% by mass to 50% by mass, based on all components excluding the solvent. By using it within this range, good adhesion between the cured product layer and the substrate can be obtained.

[0062] [Photopolymerization initiator (I)] The composition of the present invention preferably further contains a photopolymerization initiator (I). The photopolymerization initiator (I) has a catalytic action of inducing a polymerization reaction by light irradiation, and is therefore expected to improve the curability of the composition of the present invention. Examples of the photopolymerization initiator (I) include 2-ethylanthraquinone, 2,4-diethylthioxanthone, benzophenone and benzophenone derivatives thereof, 1-hydroxycyclohexyl phenyl ketone [e.g., trade name "Omnirad (registered trademark) 184", manufactured by IGM], 2,2-dimethoxy-1,2-diphenylethan-1-one [e.g., trade name "Omnirad (registered trademark) 651", manufactured by IGM], bis(2,4,6-trimethylisothiazolinone), and methylisothiazolinone. Examples of such compounds include 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (e.g., trade name "Omnirad® 819" manufactured by IGM), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one (e.g., trade name "Omnirad® 907" manufactured by IGM), and 2-hydroxy-2-methyl-1-phenylpropan-1-one (e.g., trade name "Darocure® 1173" manufactured by IGM). These compounds may be used alone or in combination of two or more. Among these, compounds having a maximum absorption wavelength in the wavelength range of 200 nm or more but less than 280 nm in the light absorption spectrum are preferred because, when a curable composition applied to a substrate is irradiated with active energy rays to form a cured layer, the curing of the deeper parts of the coating film is delayed compared to the surface, thereby enhancing adhesion between the cured layer and the substrate. Examples of such compounds include benzophenone.

[0063] The content of the photopolymerization initiator (I) in the composition of the present invention is preferably 0.1% by mass to 15% by mass, more preferably 0.5% by mass to 10% by mass, and even more preferably 1.0% by mass to 7% by mass, based on all components excluding the solvent. By using it within this range, the curability of the composition is improved and the stability of the composition is also improved.

[0064] [Particles that provide anti-glare properties (G)] Examples of the particles (G) used in the present invention that impart antiglare properties include organic particles such as acrylic particles (refractive index 1.49), acrylic-styrene copolymer particles (refractive index 1.49 to 1.59), polystyrene particles (refractive index 1.59), polycarbonate particles (refractive index 1.58), melamine particles (refractive index 1.66), epoxy particles (refractive index 1.58), polyurethane particles (refractive index 1.55), nylon particles (refractive index 1.50), polyethylene particles (1.50 to 1.56), polypropylene particles (refractive index 1.49), silicone particles (refractive index 1.43), polytetrafluoroethylene particles (refractive index 1.35), polyvinylidene fluoride particles (refractive index 1.42), polyvinyl chloride particles (refractive index 1.54), and polyvinylidene chloride particles (refractive index 1.62), as well as glass particles (refractive index 1.48) and silica particles (refractive index 1.43). These particles (G) that impart antiglare properties may be used alone or in combination of two or more. Among them, organic particles are preferred, and it is more preferred to use acrylic particles, acrylic-styrene copolymer particles, or polystyrene particles, and it is even more preferred to use crosslinked particles of these from the viewpoint of antiglare durability.

[0065] The content of the particles (G) that impart antiglare properties in the composition of the present invention is preferably 0.5% by mass to 30% by mass, more preferably 1% by mass to 20% by mass, and even more preferably 2% by mass to 15% by mass, based on all components excluding the solvent. By using the particles in this range, the cured product layer has good antiglare properties while maintaining adhesion to the substrate.

[0066] [Inorganic fine particles (S)] Furthermore, the composition of the present invention may contain inorganic fine particles (S) to improve the antiglare properties of the cured product and the curing properties of the composition. Inorganic fine particles increase the specific gravity of the cured product layer, thereby improving the antiglare properties by floating particles with low specific gravity that impart antiglare properties to the surface. Furthermore, in terms of improving the curing properties of the composition, it is preferable that the inorganic fine particles be surface-modified with a silane coupling agent having a reactive group such as a (meth)acryloyl group. Surface-modified particles can be produced, for example, by mixing a silane coupling agent having a radically polymerizable double bond such as a (meth)acryloyl group with inorganic fine particles and reacting them at 25°C to 120°C for approximately 1 hour to 24 hours. Examples of inorganic fine particles include silica, alumina, and zirconia, with silica being preferred.

[0067] The inorganic fine particles (S) preferably have an average primary particle size of 0.005 μm or more and 10 μm or less, more preferably 0.01 μm or more and 1 μm or less. Inorganic fine particles (S) within this range, which have a large specific surface area and many reactive groups introduced therein, improve the curability of the composition.

[0068] The content of inorganic fine particles (S) in the composition of the present invention is preferably 80% by mass or less, more preferably 50% by mass or less, and even more preferably 30% by mass or less, based on all components excluding the solvent. By using the inorganic fine particles (S) in this range, the curability of the composition is improved and the antiglare properties of the cured product are improved.

[0069] [Light absorber (H)] In a preferred embodiment, the composition of the present invention further contains a light absorber (H). By incorporating the light absorber (H), deterioration of the cured product layer can be prevented and the adhesion of the cured product layer can be expected to be improved. Examples of the light absorber (H) include ultraviolet absorbers and hindered amine light stabilizers.

[0070] Examples of ultraviolet absorbers include 2-(2-hydroxy-5-tert-butylphenyl)-2H-benzotriazole [e.g., trade name "Tinuvin (registered trademark) PS", manufactured by BASF] and 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bis-butyloxyphenyl)-1,3,5-triazine [e.g., trade name "Tinuvin (registered trademark) 460", manufactured by BASF].

[0071] Examples of the hindered amine light stabilizer include bis[2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidine sebacate [e.g., trade name "Tinuvin (registered trademark) 123", manufactured by BASF] and bis[1,2,2,6,6-pentamethyl-4-piperidine sebacate [e.g., trade name "Tinuvin (registered trademark) 292", manufactured by BASF].

[0072] These light absorbers (H) may be used alone or in combination of two or more. Among these, bis[2,2,6,6-tetramethyl-1-(octyloxy)-4-piperidine] sebacate is preferred because it provides good compatibility between the (meth)acrylate (M) and the acrylic polymer (P).

[0073] The content of the light absorber (H) in the composition of the present invention is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1.0% by mass or more, based on all components excluding the solvent, from the viewpoint of improving the adhesion of the cured layer, and is preferably 15% by mass or less, more preferably 10% by mass or less, and even more preferably 7% by mass or less, from the viewpoint of improving the curability.

[0074] [Other compounds] The composition of the present invention may contain "other components" other than the (meth)acrylate (M), acrylic polymer (P), photopolymerization initiator (I), light absorber (H), and (meth)acrylate (M) described above, provided that the effects of the present invention are not impaired. Examples of other components include organic solvents, fillers, silane coupling agents, antistatic agents, organic pigments, leveling agents, dispersants, thixotropy-imparting agents (thickeners), antifoaming agents, antioxidants, and photoacid generators.

[0075] The organic solvent is not particularly limited and can be appropriately selected in consideration of the types of components contained in the curable composition, etc. Specific examples of the organic solvent 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 (PGM), 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 halogenated solvents such as dichloromethane and chloroform.

[0076] The organic solvent may be used alone or in combination of two or more. Among these, aromatic solvents, alcohol solvents, and ketone solvents are preferred because they provide good compatibility between the (meth)acrylate (M) and the acrylic polymers (P1) and (P2).

[0077] [Method for producing curable composition] The method for producing the composition of the present invention is not particularly limited, and examples thereof include a method of mixing the (meth)acrylate (M), the acrylic polymers (P1) and (P2), and, if necessary, the polymerization initiator (I), the light absorber (H), a (meth)acrylate other than the (meth)acrylate (M), and other components, etc. When mixing, it is preferable to mix uniformly using a disperser, a stirrer, etc.

[0078] [Base material] The substrate on which the cured product layer of the composition of the present invention is laminated may be made of various materials, but plastic substrates are particularly suitable in terms of adhesion to the cured product layer. The substrate may be in the form of a sheet, film, or the like.

[0079] Examples of materials for the plastic substrate include polyester resin, polycarbonate resin, polyurethane resin, polyamide resin, polyimide resin, polyvinyl alcohol resin, polyethylene resin, polypropylene resin, cyclic polyolefin resin, triacetyl cellulose resin, acrylic resin, etc. Among these, triacetyl cellulose resin, acrylic resin, polyester resin, and cyclic polyolefin resin are preferred because of their good transparency and optical properties, and acrylic resin is preferred because of their good mechanical properties and heat resistance.

[0080] Furthermore, portions of the substrate other than the surface on which the cured material layer is directly laminated, such as the interior or opposite surface of the substrate, may be made of a material different from that of the surface. Examples of such different materials include polyester resins, polycarbonate resins, polyurethane resins, polyamide resins, polyimide resins, polyvinyl alcohol resins, polyethylene resins, polypropylene resins, cyclic polyolefin resins, triacetyl cellulose resins, and (meth)acrylic resins. Among these, polyester resins and polycarbonate resins are preferred because of their good transparency and heat resistance, and polyvinyl alcohol resins are preferred because of their good chemical resistance. Therefore, the substrate is preferably one in which a layer of the above-mentioned plastic substrate is laminated on a layer of one of these resins.

[0081] The substrate can be produced by any method, such as a melt extrusion method such as an inflation method or a T-die method, a solution casting method, a calendar method, etc. Furthermore, uniaxial or biaxial stretching treatment may be performed as necessary.

[0082] In addition to the resin, the base material may contain additives such as a functional polymer, an ultraviolet absorber, an antioxidant, a plasticizer, a release agent, a coloring inhibitor, a colorant, an antistatic agent, a flame retardant, a retardation reducing agent, inorganic particles, and organic particles.

[0083] [Primer layer] Although it is envisioned that the layer formed from the curable composition of the present invention will be provided directly on the substrate, a primer layer may be present between the substrate and the layer formed from the curable composition to improve adhesion, etc. A conventionally known resin can be used as the primer layer provided to improve adhesion. Specific examples of resins include acrylic resins, polyester resins, urethane resins, polyvinyl resins (polyvinyl alcohol, vinyl chloride-vinyl acetate copolymers, etc.), etc. Among these, polyester resins, acrylic resins, and urethane resins are preferred in terms of adhesion performance and ease of forming the primer layer. When the substrate layer is a resin film, the resin of the primer layer is preferably the same type of resin as the resin of the resin film from the viewpoint of affinity between the primer layer and the substrate layer. For example, when the substrate layer is a poly(meth)acrylate film, the primer layer preferably contains an acrylic resin, and when the substrate layer is a polyester film, the primer layer preferably contains a polyester resin. It is also possible to impart antistatic properties to the primer layer by using an antistatic agent.

[0084] [Surface functional layer] It is also possible to provide a surface functional layer on the layer formed from the curable composition in order to impart further functionality. Examples of the surface functional layer include an antifouling layer, an antistatic layer, a refractive index adjusting layer (antireflection layer, low reflection layer, etc.), an infrared absorbing layer, an ultraviolet absorbing layer, and a color correcting layer. The antifouling layer is provided to improve the antifouling performance by imparting water repellency and oil repellency to the concave-convex layer. Materials used for the antifouling layer include conventionally known materials such as silicone compounds, fluorine compounds, and long-chain alkyl group-containing compounds. Among these, silicone compounds and fluorine compounds are preferred for achieving stronger antifouling performance, and fluorine compounds and long-chain alkyl group-containing compounds are preferred from the viewpoint of preventing the antifouling layer from contaminating objects that come into contact with it.

[0085] Silicone compounds refer to compounds having a silicone structure in the molecule, such as alkyl silicones such as dimethyl silicone and diethyl silicone, as well as phenyl silicones and methylphenyl silicones having a phenyl group. Silicones having various functional groups can also be used, such as ether groups, hydroxyl groups, amino groups, epoxy groups, carboxylic acid groups, halogen groups such as fluorine, perfluoroalkyl groups, various alkyl groups, and hydrocarbon groups such as various aromatic groups. Other common functional groups include silicones having vinyl groups and hydrogen silicones in which hydrogen atoms are directly bonded to silicon atoms. It is also possible to use both in combination to form an addition-type silicone (a type resulting from the addition reaction of a vinyl group with a hydrogen silane). Another preferred method involves introducing a double bond such as an acryloyl group and reacting at the double bond.

[0086] Furthermore, as the silicone compound, modified silicones such as acrylic-grafted silicone, silicone-grafted acrylic, amino-modified silicone, perfluoroalkyl-modified silicone, etc. In consideration of heat resistance and contamination resistance, it is preferable to use a curable silicone resin, and any curing reaction type such as a condensation type, an addition type, or an active energy ray curable type can be used.

[0087] The fluorine compound is a compound containing fluorine atoms in the compound. As the fluorine compound, an organic fluorine compound is preferably used, for example, a perfluoroalkyl group-containing compound, a polymer of an olefin compound containing a fluorine atom, an aromatic fluorine compound such as fluorobenzene, etc. From the viewpoint of mold releasability, a compound having a perfluoroalkyl group is preferable. Furthermore, as the fluorine compound, a compound containing a long-chain alkyl compound as described below can also be used.

[0088] Examples of compounds having a perfluoroalkyl group include perfluoroalkyl group-containing (meth)acrylates such as perfluoroalkyl(meth)acrylate, perfluoroalkylmethyl(meth)acrylate, 2-perfluoroalkylethyl(meth)acrylate, 3-perfluoroalkylpropyl(meth)acrylate, 3-perfluoroalkyl-1-methylpropyl(meth)acrylate, and 3-perfluoroalkyl-2-propenyl(meth)acrylate, and polymers thereof; and perfluoroalkyl group-containing vinyl ethers such as perfluoroalkylmethylvinylether, 2-perfluoroalkylethylvinylether, 3-perfluoropropylvinylether, 3-perfluoroalkyl-1-methylpropylvinylether, and 3-perfluoroalkyl-2-propenylvinylether, and polymers thereof. Considering heat resistance and stain resistance, polymers are preferred. The polymer may be a single compound or a polymer of multiple compounds. Furthermore, from the viewpoint of stain resistance, the perfluoroalkyl group preferably has from 3 to 11 carbon atoms. Furthermore, the polymer may be a polymer with a compound containing a long-chain alkyl compound, as described below.

[0089] A long-chain alkyl group-containing compound is a compound having a linear or branched alkyl group with a carbon number of typically 6 or more, preferably 8 or more, and more preferably 12 or more. Examples of alkyl groups include hexyl, octyl, decyl, lauryl, octadecyl, and behenyl. Examples of compounds having an alkyl group include various long-chain alkyl group-containing polymeric compounds, long-chain alkyl group-containing amine compounds, long-chain alkyl group-containing ether compounds, and long-chain alkyl group-containing quaternary ammonium salts. In consideration of heat resistance and stain resistance, polymeric compounds are preferred. Furthermore, from the viewpoint of effectively achieving stain resistance, polymeric compounds having a long-chain alkyl group in the side chain are more preferred.

[0090] A polymer compound having a long-chain alkyl group in its side chain can be obtained by reacting a polymer having a reactive group with a compound having an alkyl group capable of reacting with the reactive group. Examples of the reactive group include a hydroxyl group, an amino group, a carboxyl group, and an acid anhydride. Examples of compounds having these reactive groups include polyvinyl alcohol, polyethyleneimine, polyethyleneamine, reactive group-containing polyester resins, and reactive group-containing poly(meth)acrylic resins. Among these, polyvinyl alcohol is preferred in terms of its antifouling properties and ease of handling.

[0091] Examples of compounds having an alkyl group capable of reacting with the reactive group include long-chain alkyl group-containing isocyanates such as hexyl isocyanate, octyl isocyanate, decyl isocyanate, lauryl isocyanate, octadecyl isocyanate, and behenyl isocyanate, long-chain alkyl group-containing acid chlorides such as hexyl chloride, octyl chloride, decyl chloride, lauryl chloride, octadecyl chloride, and behenyl chloride, long-chain alkyl group-containing amines, and long-chain alkyl group-containing alcohols. Among these, in consideration of releasability and ease of handling, long-chain alkyl group-containing isocyanates are preferred, and octadecyl isocyanate is particularly preferred.

[0092] Furthermore, polymeric compounds having long-chain alkyl groups in their side chains can also be obtained by polymerizing long-chain alkyl (meth)acrylates or copolymerizing long-chain alkyl (meth)acrylates with other vinyl group-containing monomers. Examples of long-chain alkyl (meth)acrylates include hexyl (meth)acrylate, octyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, octadecyl (meth)acrylate, and behenyl (meth)acrylate.

[0093] The content of the antifouling material in the surface functional layer required to achieve the above-mentioned antifouling performance depends on the material used and cannot be generalized. However, in the case of silicone compounds or fluorine compounds, it is usually 0.01% by mass or more, more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more, and the upper limit may be 100% by mass. Furthermore, when a long-chain alkyl group-containing compound is used, it is usually 0.1% by mass or more, preferably 1% by mass or more, and even more preferably 3% by mass or more, and the upper limit may be 100% by mass. Using the above range can provide effective antifouling performance.

[0094] Various conventionally known antistatic agents can be used as antistatic agents when forming an antistatic layer as a surface functional layer. Another preferred method involves introducing a double bond, such as an acryloyl group, into a compound having an ammonium group and then reacting the double bond. Specifically, the polymer (T) contains a monomer unit having a quaternary ammonium base, such as a quaternary ammonium salt of an N,N-dialkylamino group-containing monomer. Such a polymer (T) can be produced, for example, by homopolymerizing a monomer having a quaternary ammonium base or copolymerizing it with other monomers.

[0095] Examples of N,N-dialkylamino group-containing monomers include (meth)acrylic acid esters of amino alcohols, specifically N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N,N-diethylaminopropyl (meth)acrylate, N,N-dimethylaminobutyl (meth)acrylate, N,N-diethylaminobutyl (meth)acrylate, and N,N-dihydroxyethylaminoethyl (meth)acrylate, with N,N-dimethylaminoethyl (meth)acrylate being particularly preferred. The two alkyl groups in the N,N-dialkylamino group may be different.

[0096] Examples of quaternary ammonium salts of N,N-dialkylamino group-containing monomers include commercially available quaternized products of N,N-dimethylaminoethyl methacrylate with methyl chloride [for example, trade name "Light Ester (registered trademark) DQ-100", manufactured by Kyoeisha Chemical Co., Ltd.]. Quaternary ammonium salts of N,N-dialkylamino group-containing monomers can also be produced by a quaternization reaction of a (meth)acrylic acid ester of an amino alcohol.

[0097] The polymer (T) may contain polymerizable monomer units other than the monomer having a quaternary ammonium salt group. Examples of such polymerizable monomers include alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, and tridecyl (meth)acrylate; (meth)acrylic acid esters of the above amino alcohols; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and the like. hydroxyalkyl (meth)acrylates such as hydroxybutyl (meth)acrylate; various (meth)acrylates such as benzyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, ethyl carbitol (meth)acrylate, butoxyethyl (meth)acrylate, cyanoethyl (meth)acrylate, and glycidyl (meth)acrylate; styrene; and methylstyrene. These may be used alone or in combination of two or more. Among these, polymerizable monomers having a highly hydrophobic long-chain alkyl group are preferred because they can segregate the polymer (T) at the air interface of the cured material layer, thereby enhancing the antistatic properties of the cured material layer. Examples of such polymerizable monomers having a long chain alkyl group include stearyl (meth)acrylate, lauryl (meth)acrylate, and tridecyl (meth)acrylate.

[0098] The proportion of the quaternary ammonium salt group-containing monomer units in the polymer (T) is preferably from 10 to 90% by mass, more preferably from 20 to 70% by mass. The higher this proportion, the higher the antistatic properties, and the lower this proportion, the more the transparency of the cured product layer tends to improve.

[0099] The weight average molecular weight of the polymer (T) is preferably 800 or more and 120,000 or less, and more preferably 2,000 or more and 60,000 or less.

[0100] The polymer (T) can be produced by a radical polymerization reaction using the above-mentioned raw material monomers. The radical polymerization reaction is preferably carried out in an organic solvent in the presence of a radical polymerization initiator.

[0101] Examples of organic solvents used in radical polymerization reactions include ketone solvents such as acetone and methyl ethyl ketone (MEK); alcohol solvents such as ethanol, methanol, isopropyl alcohol (IPA), and isobutanol; ether solvents such as ethylene glycol dimethyl ether and propylene glycol monomethyl ether; ester solvents such as ethyl acetate, propylene glycol monomethyl ether acetate, and 2-ethoxyethyl acetate; and aromatic hydrocarbon solvents such as toluene. These organic solvents may be used alone or in combination of two or more.

[0102] Examples of radical polymerization initiators used in radical polymerization reactions include organic peroxides such as benzoyl peroxide and di-t-butyl peroxide; and azo compounds such as 2,2'-azobisbutyronitrile, 2,2'-azobis(2,4-dimethylvaleronitrile), and 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile). These radical polymerization initiators may be used alone or in combination of two or more. The radical polymerization initiator is preferably used in an amount of 0.01% by mass or more and 5% by mass or less relative to 100% by mass of the total raw material monomers.

[0103] In addition, during the radical polymerization reaction, a chain transfer agent can be used for the purpose of controlling the weight average molecular weight of the polymer (T). Examples of the chain transfer agent include butanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, octyl 2-mercaptopropionate, octyl 3-mercaptopropionate, 2-ethylhexyl mercaptopropionate, 2-ethylhexyl thioglycolate, butyl-3-mercaptopropionate, mercaptopropyltrimethoxysilane, methyl-3-mercaptopropionate, 2,2-(ethylenediaminetetraacetic acid)-2-methylpropanol, methyl-3-mercaptopropionate ... Examples of the thiol-based compounds include (oxy)diethanethiol, ethanethiol, 4-methylbenzenethiol, octanoic acid 2-mercaptoethyl ester, 1,8-dimercapto-3,6-dioxaoctane, decantrithiol, dodecyl mercaptan, diphenyl sulfoxide, dibenzyl sulfide, 2,3-dimethylcapto-1-propanol, mercaptoethanol, thiosalicylic acid, thioglycerol, thioglycolic acid, 3-mercaptopropionic acid, thiomalic acid, mercaptoacetic acid, mercaptosuccinic acid, and 2-mercaptoethanesulfonic acid. These may be used alone or in combination of two or more.

[0104] The amount of the chain transfer agent used is preferably 0.1% by mass to 25% by mass, more preferably 0.5% by mass to 20% by mass, and even more preferably 1.0% by mass to 15% by mass, based on 100% by mass of the total raw material monomers.

[0105] The reaction time for the radical polymerization reaction is preferably from 1 to 20 hours, more preferably from 3 to 12 hours, and the reaction temperature is preferably from 40 to 120°C, more preferably from 50 to 100°C.

[0106] The proportion of the polymer (T) in the antistatic agent composition is preferably from 1 to 80% by mass, more preferably from 2 to 60% by mass, even more preferably from 3 to 40% by mass, and particularly preferably from 4 to 30% by mass, based on all components excluding the solvent. By using the polymer (T) in this range, it becomes easier to achieve both antistatic properties and transparency of the cured product layer.

[0107] As a component other than the polymer (T), it is preferable to use a (meth)acrylate having a radically polymerizable double bond in order to improve the hardness of the antistatic layer. For example, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, tris-2-hydroxyethyl isocyanurate tri(meth)acrylate, glycerin tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ditrimethylolpropane hexa(meth)acrylate. modified products of polyfunctional (meth)acrylate compounds in which part of these trifunctional or higher polyfunctional (meth)acrylates is substituted with an alkyl group or ε-caprolactone; polyfunctional (meth)acrylates having a nitrogen atom-containing heterocyclic structure such as an isocyanurate structure; polyfunctional (meth)acrylates having a multi-branched resinous structure such as a polyfunctional (meth)acrylate having a dendrimer structure and a polyfunctional (meth)acrylate having a hyperbranched structure; and urethane (meth)acrylates in which a (meth)acrylate having a hydroxyl group, such as pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, or dipentaerythritol penta(meth)acrylate, is added to an isocyanate, triisocyanate, or isocyanurate. Among these, from the viewpoint of compatibility with the acrylic polymer (P), pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferred, and dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate are more preferred.

[0108] Examples of the refractive index adjusting layer include a high refractive index layer, a low refractive index layer, and a laminate thereof. Materials used to form the refractive index adjusting layer as a surface functional layer, when the purpose is to increase the refractive index, include aromatic compounds such as benzene structures, bisphenol A structures, melamine structures, and fluorene structures, as well as condensed polycyclic aromatic compounds such as naphthalene, anthracene, phenanthrene, naphthacene, benzo[a]anthracene, benzo[a]phenanthrene, pyrene, benzo[c]phenanthrene, and perylene structures, which are considered to be high refractive index compounds among aromatic compounds, metal oxides such as zirconium oxide, titanium oxide, zinc oxide, tin oxide, antimony oxide, yttrium oxide, indium oxide, cerium oxide, ATO (antimony tin oxide), and ITO (indium tin oxide), metal-containing compounds such as metal chelate compounds such as titanium chelate and zirconium chelate, sulfur-containing compounds, and halogen-containing compounds.

[0109] Metal oxides are preferably used in the form of particles, since there is a concern that their adhesion may decrease depending on the form of use. From the viewpoint of coating appearance, the average particle size is preferably 100 nm or less, more preferably 50 nm or less, and even more preferably 25 nm or less.

[0110] When forming a refractive index adjusting layer as a surface functional layer, conventionally known materials can be used if the objective is to lower the refractive index. For example, acrylic resins and urethane resins are generally possible because they have low refractive indices. In particular, compounds in which fluorine atoms are incorporated into the resin, such as fluororesins, compounds containing fluororesins in the main skeleton, and compounds containing perfluoroalkyl groups in the side chain, can be used. In addition, inorganic materials include hollow silica particles, fluorine atom-containing inorganic compounds such as magnesium fluoride and calcium fluoride, and hollow particles and nanoporous particles thereof.

[0111] The thickness of the surface functional layer is not particularly limited, but is usually in the range of 0.001 μm to 10 μm, preferably 0.005 μm to 5 μm, more preferably 0.01 μm to 1 μm, even more preferably 0.02 μm to 0.5 μm, and particularly preferably 0.03 μm to 0.2 μm. By using it in the above range, it is possible to achieve both the function of the surface functional layer and the performance of the layer formed from the curable composition. The surface functional layer can be formed by a conventionally known method.

[0112] [Back functional layer] Furthermore, a back functional layer may be provided on the surface of the substrate opposite to the surface on which the layer formed from the curable composition is provided. Examples of the back functional layer include an adhesive layer, an antistatic layer, a refractive index adjusting layer, and an antiblocking layer.

[0113] The adhesive layer is provided to bond the laminate to various adherends. The antistatic layer is provided to prevent adhesion of surrounding dust and the like due to peeling electrification or frictional electrification to the outermost surface of the laminate, particularly the outermost surface of the base layer opposite the uneven layer side, 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.

[0114] The adhesive layer may be formed from a known adhesive, such as an acrylic adhesive, a polyester adhesive, a urethane adhesive, a rubber adhesive, etc. Among these, an acrylic adhesive is preferred in view of versatility.

[0115] The antistatic layer and the refractive index adjusting layer are similar to the antistatic layer and the refractive index adjusting layer as the surface functional layer, respectively.

[0116] The thickness of the back functional layer cannot be generalized because it depends on the material used in the back functional layer and the performance to be achieved, but it is, for example, 0.001 μm to 30 μm. When the back functional layer is an adhesive layer, it is preferably 0.01 μm to 30 μm, more preferably 0.1 μm to 20 μm. When the back functional layer is an antistatic layer, it is preferably 0.001 μm to 10 μm, more preferably 0.01 μm to 5 μm. The back surface functional layer can be formed by a conventionally known method.

[0117] [Laminate] The method for producing a laminate by laminating a cured product layer of the composition of the present invention on a substrate is not particularly limited, and examples thereof include a method in which the composition of the present invention is applied to the surface of the substrate and cured. Note that the laminate may have a cured product layer formed on only a portion of the surface of the substrate, for example, only one side when the substrate is in the form of a sheet or film, or may have a cured product layer formed on the other side, for example, the back side when the substrate is in the form of a sheet or film. The cured product layer functions as a hard coat layer for the substrate.

[0118] Examples of methods for applying the composition of the present invention to a substrate include reverse coating, gravure coating, rod coating, bar coating, Mayer bar coating, die coating, and spray coating.

[0119] A method for curing the composition applied to a substrate preferably includes drying the composition at a temperature of from 40° C. to 100° C., more preferably from 50° C. to 90° C., followed by irradiation with active energy rays at a temperature of from 40° C. to 100° C. Examples of active energy rays include ultraviolet rays, electron beams, X-rays, infrared rays, and visible light. Of these, ultraviolet rays and electron beams are preferred from the viewpoints of curability and prevention of deterioration of the substrate.

[0120] When ultraviolet rays are used as the active energy rays, various ultraviolet irradiation devices can be used. The light source of the ultraviolet irradiation device can be a xenon lamp, a high-pressure mercury lamp, a metal halide lamp, an LED-UV lamp, or the like.

[0121] The amount of ultraviolet light irradiation is determined appropriately depending on the reaction rate of the (meth)acryloyl group required in the curing process, but is usually 10 mJ / cm 2 More than 10000mJ / cm 2 In view of the curability of the curable composition, the flexibility of the cured product, etc., 2 More than 5000mJ / cm 2 Less than 30 mJ / cm is preferred 2 More than 3000mJ / cm 2 Less than 50 mJ / cm is more preferable. 2 More than 1000mJ / cm 2 It is even more preferable that: Furthermore, when productivity is to be improved, it is preferable to have an even lower irradiation dose, such as 500 mJ / cm 2 Below that, even 400mJ / cm 2 Below, especially 200mJ / cm 2 The following are preferred: The composition of the present invention is characterized in that it easily exhibits its performance even with a small amount of irradiation.

[0122] The ultraviolet irradiance is 50mW / cm 2 More than 600mW / cm 2 Less than 75mW / cm is preferred 2 More than 450mW / cm 2 Less than 100 mW / cm is more preferable. 2 More than 300mW / cm 2 The following is even more preferred:

[0123] When electron beams are used as the active energy rays, various electron beam irradiation devices can be used. The irradiation dose of electron beams is determined appropriately depending on the reaction rate of the (meth)acryloyl group required in the curing step, but is usually 0.5 Mrad or more and 20 Mrad or less. From the viewpoints of the curability of the composition, the flexibility of the cured product, and prevention of damage to the substrate, a dose of 1 Mrad or more and 15 Mrad or less is preferred.

[0124] In forming the cured product layer, the composition of the present invention may be applied and cured only once or multiple times. Repeating the application and curing multiple times can prevent warping of the substrate.

[0125] The thickness of the cured product layer is preferably 1 μm or more, more preferably 1.5 μm or more, and even more preferably 2 μm or more from the viewpoint of surface hardness of the resulting laminate, and is preferably 50 μm or less, more preferably 30 μm or less, even more preferably 10 μm or less, and particularly preferably 5 μm or less from the viewpoint of crack resistance and adhesion.

[0126] The thickness of the substrate is not limited. When the substrate is in the form of a film, the thickness is preferably from 5 μm to 3 mm, more preferably from 10 μm to 2 mm, further preferably from 15 μm to 1 mm, and particularly preferably from 20 μm to 250 μm.

[0127] The thickness of the laminate is also optional. In the case of a film-like laminate, the thickness of the laminate is preferably 6 μm or more, more preferably 10 μm or more, and even more preferably 15 μm or more, because each layer needs to fully exhibit its respective function. Furthermore, in view of the demand for thinner and lighter products to which the laminate is applied, the thickness of the laminate is preferably 3 mm or less, more preferably 2 mm or less, even more preferably 1 mm or less, and particularly preferably 300 μm or less.

[0128] A laminate obtained by laminating a cured product layer of the composition of the present invention as a hard coat layer on a substrate exhibits excellent adhesion between the substrate and the hard coat layer and excellent scratch resistance. Therefore, the laminate can be suitably used for surface covers of a wide range of products, including optical display components for liquid crystal televisions, organic electroluminescent (EL) televisions, electronic paper, touch panels, smartphones, etc.; automobile-related components such as lamp-related products and window-related products (rear windows, side windows, skylights, etc.); and household items such as housings for various electrical devices, decorative panels, and furniture. Among these, the laminate is suitable for optical display components, and particularly suitable for use as a polarizer protective film or display protective film that is attached to a polarizer in the production of a polarizing plate for a display.

[0129] [Polarizer protection film, polarizing plate] The polarizer protective film of the present invention is a laminate in which a hard coat layer made of a cured product of the composition of the present invention is laminated on only one side of a plastic film. The polarizing plate of the present invention is obtained by bonding the side of the polarizer protective film of the present invention that does not have the hard coat layer to a polarizer. The polarizer protective film can be bonded to one or both sides of the polarizer. An adhesive, a pressure-sensitive adhesive, or the like can be used for bonding. [Example]

[0130] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention.

[0131] [Weight average molecular weight (Mw) of acrylic polymer (P)] The weight-average molecular weight (Mw) of the acrylic polymer (P) was measured using a gel permeation chromatography (GPC) "HLC-8120" (manufactured by Tosoh Corporation). The column used was a TSKgel G5000HXL*GMHXL-L (manufactured by Tosoh Corporation). A calibration curve was prepared using standard polystyrenes F288 / F80 / F40 / F10 / F4 / F1 / A5000 / A1000 / A500 (manufactured by Tosoh Corporation) and styrene. The measurement was carried out using 100 μl of a solution prepared by dissolving the polymer in tetrahydrofuran to a concentration of 0.4%, at a column oven temperature of 40° C. The weight average molecular weight (Mw) was calculated in terms of standard polystyrene.

[0132] The examples and comparative examples were evaluated by the following methods. [Adhesion evaluation] The surface of the laminate on the side of the cured product layer was evaluated according to the JIS K-5400 cross-cut peel test (number of cross-cuts: 100), and the number of squares remaining after the peel test was evaluated. The more squares remaining, the better the adhesion. In particular, for initial adhesion (adhesion without a weather resistance test), it is important that there is no peeling, preferably 96 or more, more preferably 98 or more, and even more preferably 100 (no peeling), and 100 is important for use in various applications.

[0133] [Anti-glare evaluation] Since the antiglare properties of a laminate correlate with haze, the laminate was evaluated based on its haze measurement. Haze was measured using a haze meter "HM-65W" manufactured by Murakami Color Research Laboratory in accordance with JIS Z8722:2009 (Geometric conditions for irradiating and receiving light on a transparent object) and JIS K7136:2000 (Method for determining haze for plastics - transparent materials). The evaluation results indicate that the higher the haze measurement value, the better the antiglare properties, and the haze is preferably 10% or more, more preferably 20% or more, and even more preferably 30% or more. There is no particular upper limit, but it is preferably 90% or less.

[0134] [Evaluation of curability] The curability of the curable composition was evaluated by curing a coating of the curable composition by ultraviolet irradiation as shown below, based on the number of irradiation passes required for sufficient curing. Sufficient curing was determined by touching the coating with a finger after each irradiation pass to check for the presence or absence of tackiness. If tackiness was present, ultraviolet irradiation was repeated until the tackiness disappeared, and the number of irradiation passes required until the tackiness disappeared was recorded. The evaluation results indicated that the fewer the number of irradiation passes, the better the curability, with one pass being preferred.

[0135] [Evaluation of antistatic properties] The laminate was conditioned for 24 hours in a temperature-controlled room at 23°C and 50% RH. After that, in the same temperature-controlled room, a high-resistance resistivity meter ("Hiresta-UP MCP-HT450" manufactured by Mitsubishi Chemical Analytech Co., Ltd.) was used to apply a voltage of 500V to the surface of the cured layer of the laminate, and the surface resistivity was measured, which was used as an index of antistatic properties. The smaller the surface resistivity, the better the antistatic properties, and preferably 10 13 Ω / sq. or less, preferably 10 12 Ω / sq. or less, more preferably 10 11 There is no particular lower limit, but it is preferably 100 Ω or more.

[0136] [(Meth)acrylate (M)] The following commercially available products were used as the (meth)acrylate (M) having three or more radically polymerizable double bonds. (B-1-I) Viscoat (registered trademark) #300 (Osaka Organic Chemical Industry Ltd.) A mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (B-1-II) Kayarad (registered trademark) DPHA (manufactured by Nippon Kayaku Co., Ltd.) Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate (B-1-III) Aronix (registered trademark) M-403 (manufactured by Toagosei Co., Ltd.) Mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate thing ( B-1-V) Aronix (registered trademark) M-510 (manufactured by Toagosei Co., Ltd.) A mixture of succinic anhydride-modified pentaerythritol triacrylate and pentaerythritol tetraacrylate [Other (meth)acrylates] (B-1-IV) Miramer (registered trademark) M200 (Miwon Specialty Chemical Co., Ltd.) 1,6-Hexanediol diacrylate

[0137] [Acrylic polymer (P1)] As the acrylic polymer (P1), polymers (B-2-I) to (B-2-III) produced by the methods described in the following Production Examples 2-1 to 2-3 were used.

[0138] [Production Example 1-1] Production of (B-2-I) A flask equipped with a thermometer, a stirrer, and a reflux condenser was charged with 178 mass% propylene glycol monomethyl ether (PGM), 20 mass% glycidyl methacrylate (GMA), 79 mass% methyl methacrylate (MMA), 1.0 mass% ethyl acrylate (EA), and 0.6 mass% 2,2'-azobis(2,4-dimethylvaleronitrile) (V-65, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), and the mixture was reacted at 65°C for 3 hours. Thereafter, 0.3% by mass of V-65 was further added and reacted for 3 hours, after which 48% by mass of PGM and 0.5% by mass of 4-methoxyphenol (MEHQ) were added and the mixture was heated to 100°C. Next, 10% by mass of acrylic acid (AA) and 1.6% by mass of triphenylphosphine were added and reacted at 110°C for 6 hours to obtain an acrylic polymer (B-2-I). The acrylic polymer (B-2-I) had a glass transition temperature (Tg) of 88°C, a weight average molecular weight (Mw) of 48,800, and a hydroxyl value (OHV) of 91 mgKOH / g.

[0139] [Production Example 1-2] Production of (B-2-II) An acrylic polymer (B-2-II) was obtained in the same manner as in Production Example 1-1, except that the GMA content was 66% by mass, the MMA content was 33% by mass, and the AA content was 33% by mass. The Tg of the acrylic polymer (B-2-II) was 53°C, the Mw was 31,800, and the OHV was 211 mgKOH / g.

[0140] [Production Example 1-3] Production of (B-2-III) A flask equipped with a thermometer, a stirrer, and a reflux condenser was charged with 33.8 mass% xylene, 20 mass% butyl acetate, 10 mass% styrene, 49 mass% n-butyl methacrylate, 15.2 mass% isobutyl methacrylate, 22.8 mass% 2-hydroxyethyl acrylate, 3 mass% monomethyl maleate, 2 mass% 2,2'-azobisisobutyronitrile, and 2.5 mass% t-butylperoxy-2-ethylhexanoate, and the mixture was reacted at 130°C for 4 hours. Then, 12% by mass of xylene and 0.1% by mass of 2,2'-azobisisobutyronitrile were added and reacted for 3 hours to obtain an acrylic polymer (B-2-III). The acrylic polymer (B-2-III) had a Tg of 20°C, an Mw of 8700, and an OHV of 110 mgKOH / g.

[0141] [Acrylic polymer (P2)] As the acrylic polymer (P2) different from (P1), polymers (B-3-I) and (B-3-II) produced by the methods described in the following Production Examples 2-1 to 2-4 were used.

[0142] [Production Example 2-1] Production of Dispersant (X) A flask equipped with a stirrer, condenser, and thermometer was charged with 900% by weight of deionized water, 60% by weight of 2-sulfoethyl sodium methacrylate, 10% by weight of potassium methacrylate, and 12% by weight of MMA. The contents were stirred and the flask was purged with nitrogen while the temperature was raised to 50°C. Next, 0.08% by weight of 2,2'-azobis(2-methylpropionamidine) dihydrochloride was added as a polymerization initiator to the flask, and the temperature was further raised to 60°C. After the temperature was raised, 18 parts of MMA were continuously added dropwise at a rate of 0.24% by weight / min using a dropping pump. The resulting reaction solution was maintained at 60°C for 6 hours and then cooled to room temperature to obtain a transparent aqueous solution of dispersant (X) with a solids content of 10%.

[0143] [Production Example 2-2] Production of chain transfer agent (Y) In a flask equipped with a stirrer, 1.00 g of cobalt(II) acetate tetrahydrate, 1.93 g of diphenylglyoxime, and 80 ml of diethyl ether previously deoxygenated by nitrogen bubbling were placed under a nitrogen atmosphere and stirred at room temperature for 30 minutes. Next, 10 ml of boron trifluoride diethyl ether complex was added, and the mixture was stirred for an additional 6 hours. The resulting reaction mixture was filtered, and the solid was washed with diethyl ether and dried in vacuo for 15 hours to obtain 2.12 g of chain transfer agent (Y) as a reddish-brown solid.

[0144] [Production Example 2-3] Production of Polymer (B-3-I) A flask equipped with a stirrer, a condenser, and a thermometer was charged with 145% by mass of deionized water, 0.1 parts by mass of sodium sulfate, and 0.25 parts by mass of dispersant (X), and the resulting mixture was stirred to form a homogeneous aqueous solution. A monomer mixture of 100% by mass of MMA, 0.005% by mass of chain transfer agent (Y), and 0.4% by mass of 2,2'-azobis(2-methylbutyronitrile) was then added to the flask to form an aqueous suspension. The atmosphere in the flask was then purged with nitrogen, the temperature was raised to 80°C, and the reaction was allowed to proceed for approximately 1 hour. To further increase the polymerization rate, the temperature was raised to 93°C and maintained at this temperature for 1 hour. The reaction solution was then cooled to 40°C to obtain an aqueous polymer suspension. The polymer contained in this aqueous polymer suspension was filtered using a nylon filter cloth with a 45 μm mesh, washed with deionized water, and then dried at 40°C for 16 hours to obtain an acrylic polymer (B-3-I). The acrylic polymer (B-3-I) had a Tg of 82°C and an Mw of 7,800.

[0145] [Production Example 2-4] Production of Polymer (B-3-II) An acrylic polymer (B-3-II) was obtained in the same manner as in Production Example 2-3, except that the GMA content and MMA content were changed to 50% by mass and 50% by mass, respectively. The Tg of the acrylic polymer (B-3-II) was 59°C and the Mw was 6,800.

[0146] [Polymers containing quaternary ammonium salt groups] (T) ] Polymers containing quaternary ammonium salt groups (T) As a result, the method described in the following Production Example 3-1 The solution of the polymer (B-4-I) having quaternary ammonium salt groups prepared in the above step was used.

[0147] [Production Example 3-1] Production of Polymer (B-4-I) A reactor equipped with a stirrer, reflux condenser, and thermometer was charged with 18% by mass of (methacryloyloxyethyl)trimethylammonium chloride (Light Ester (registered trademark) DQ-100, manufactured by Kyoeisha Chemical Co., Ltd.), 7.5% by mass of a mixture of lauryl methacrylate and tridecyl methacrylate (Acryester SL, manufactured by Mitsubishi Chemical Corporation), 4.5% by mass of N,N-dimethylaminoethyl methacrylate (Acryester DM, manufactured by Mitsubishi Chemical Corporation), 20% by mass of methyl ethyl ketone (MEK), and 50% by mass of isopropyl alcohol (IPA). After stirring began, the system was purged with nitrogen and heated to 55°C. 0.6% by mass of V-65 was added, and the system was heated to 65°C and stirred for 3 hours. Another 0.6% by mass of V-65 was then added, and the mixture was stirred at 65°C for 3 hours. The system was heated to 80°C, stirred for 2 hours, and then cooled to room temperature to obtain a solution of polymer (B-4-I). The composition of this solution was polymer (B-4-I) / MEK / IPA = 30 / 20 / 50 (mass ratio). The Mw of polymer (B-4-I) was 45,200.

[0148] As the photopolymerization initiator (I), the following commercially available product was used. (C-1-I) Benzophenone (manufactured by Daido Chemical Industry Co., Ltd.) (C-1-II) 1-Hydroxycyclohexyl phenyl ketone (Omnirad-184, manufactured by BASF)

[0149] The following commercially available products were used as particles (G) that impart antiglare properties. (E-1) Crosslinked acrylic monodisperse particles MX-500 (manufactured by Soken Chemical & Engineering Co., Ltd.)

[0150] [Inorganic fine particles (S)] As the inorganic fine particles (S), inorganic fine particles (D-1) produced by the method described in the following Production Example 4-1 were used. [Production Example 4-1] Production of inorganic fine particles (D-1) A reactor equipped with a stirrer, reflux condenser, and thermometer was charged with 84% by mass of methanol silica sol (average primary particle diameter 0.012 μm, manufactured by Nissan Chemical Co., Ltd.), 16% by mass of 3-methacryloxypropyltrimethoxysilane (KBM-503, manufactured by Shin-Etsu Chemical Co., Ltd.), and 0.002% by mass of MEHQ to prevent polymerization. Air was circulated through the system. After stirring began, the temperature was raised to 60°C, and 2.3% by mass of deionized water was added. The methanol contained in the methanol silica sol and some of the methanol produced by the reaction were distilled off over 2 hours. Heating was stopped, and then 4.3% by mass of toluene and 0.003% by mass of MEHQ were added. The temperature was raised to 90°C, and the methanol was completely distilled off. The solvent was replaced with toluene, yielding a toluene dispersion of inorganic microparticles (D-1) surface-modified with a silane coupling agent having a methacryloyl group. The composition of this dispersion was inorganic fine particles (D-1) / toluene=60 / 40 (mass ratio).

[0151] The following films were used as substrates: (F-1) A film (acrylic resin film) in which a polymethyl methacrylate layer and a polyethylene terephthalate layer are laminated, with the polymethyl methacrylate layer side of 40 μm thick used (F-2) T602E50 (Mitsubishi Chemical Corporation) 50 μm thick PET film (F-3) TG40UL (Fujifilm Corporation) 40 μm thick TAC film

[0152] [Example 1] A curable composition was obtained by mixing 13.9 mass% of "B-1-I" as the (meth)acrylate (M), 32.6 mass% of "B-1-II", 13.9 mass% of "B-2-I" as the acrylic polymer (P1), 32.6 mass% of "B-3-I" as the acrylic polymer (P2), 2.3 mass% of "C-1-I" as the photopolymerization initiator (I), and 4.7 mass% of "E-1" as the particles (G) that impart antiglare properties, and diluting this with toluene as a solvent to a solids concentration of 40 mass%.

[0153] The obtained curable composition was thoroughly stirred with a stirrer, and then coated onto the polymethyl methacrylate layer side of the acrylic resin film "F-1" as the substrate using a bar coater #6 so that the coating thickness after drying would be 3 μm, and then heated and dried at 80° C. for 1 minute. The coating of the curable composition was exposed to UV irradiance of 120 mW / cm using "US5-X0401" manufactured by Iwasaki Electric Co., Ltd., which uses a high-pressure mercury lamp as a light source. 2 , the cumulative light intensity is 200mJ / cm in one irradiation pass 2 The curable composition was cured by irradiating it with ultraviolet light, and a cured product layer was laminated on the surface of the substrate on the side of the polymethyl methacrylate layer, thereby obtaining a laminate.

[0154] The obtained laminate was evaluated for adhesion, antiglare properties, and curability. The evaluation results were all good, with adhesion of 100, antiglare properties (haze) of 33%, and curing with one pass of UV light. The composition of the curable composition (unit: mass%) and the evaluation results are shown in Table 1.

[0155] [Examples 2 to 7] A laminate was obtained by laminating a cured product layer in the same manner as in Example 1, except that the formulation of the curable composition was changed as shown in Table 1. The evaluation results of the obtained laminate are shown in Table 1.

[0156] [Examples 8 to 9] A laminate was obtained by laminating a cured product layer in the same manner as in Example 1, except that the substrate was changed as shown in Table 1. The evaluation results of the obtained laminate are as shown in Table 1.

[0157] [Example 10] An antistatic layer was laminated on the coating film obtained in Example 1. For the antistatic layer, a curable composition was prepared by mixing 38.9 mass% of a solution of "B-4-I" (11.7 mass% of "B-4-I") produced in Production Example 3-1 as a polymer having a quaternary ammonium salt group, 70.8 mass% of (meth)acrylate (M) "(B-1-II)", 6.0 mass% of "(B-1-V)", and 11.5 mass% of Omnirad-184 "C-1-II", and diluting the mixture with solvents IPA, normal butanol (n-BuOH), and MEK to a solids concentration of 3 mass%.

[0158] The obtained curable composition was applied onto the coating film obtained in Example 1 using a bar coater #3 so that the coating film thickness after drying would be 0.1 μm, and then heated and dried at 80° C. for 1 minute. The coating film of the curable composition was then exposed to UV light at a UV irradiance of 120 mW / cm using a high-pressure mercury lamp "US5-X0401" manufactured by Iwasaki Electric Co., Ltd. as a light source. 2 The cumulative light intensity is 200mJ / cm 2 The curable composition was cured by one pass of irradiation with ultraviolet light so that the curable composition satisfies the following conditions, thereby obtaining a laminate having an antistatic layer laminated thereon.

[0159] The obtained laminate was evaluated for adhesion, antiglare property, curability, and antistatic property. The evaluation results were: adhesion: 100, antiglare property (haze): 21%, curing with one pass of ultraviolet light, and surface resistivity: 5.4 × 10 11 The results were good in both Ω / sq. The composition of the curable composition (unit: mass %) and the evaluation results are shown in Table 2.

[0160] [Comparative Examples 1 to 5] A laminate was obtained by laminating a cured product layer in the same manner as in Example 1, except that the composition of the curable composition was changed as shown in Table 3. As shown in Table 3, the evaluation results of the obtained laminate were poor in at least one of adhesion, antiglare property, and curability.

[0161] [Table 1]

[0162] [Table 2]

[0163] [Table 3]

[0164] The abbreviations in Tables 1 to 3 are as follows: PGM: Propylene glycol monomethyl ether IPA: Isopropyl alcohol n-BuOH: normal butanol MEK: Methyl ethyl ketone [Industrial Applicability]

[0165] A laminate obtained by laminating a cured product layer of the composition of the present invention as a hard coat layer on a substrate can be widely used in optical display components such as liquid crystal televisions, organic EL televisions, electronic paper, touch panels, smartphones, etc. In particular, it can be suitably used as a polarizer protective film to be attached to a polarizer in the production of a polarizing plate for a display, or as a display protective film.

Claims

1. The composition comprises a (meth)acrylate (M) having three or more radically polymerizable double bonds, an acrylic polymer (P1) having a hydroxyl group, and an acrylic polymer (P2) other than the acrylic polymer (P1) having a hydroxyl group, the acrylic polymer (P1) is a polymer having a weight average molecular weight of 31,800 or more and 100,000 or less, The curable composition, wherein the acrylic polymer (P2) is a polymer composed of structural units derived from methyl methacrylate in an amount of 70% or more by mass and has a weight average molecular weight of 1,000 or more and 20,000 or less.

2. The curable composition according to claim 1, further comprising a photopolymerization initiator (I).

3. The curable composition according to claim 1 or 2, wherein the (meth)acrylate (M) has 4 or more and 15 or less radically polymerizable double bonds.

4. The curable composition according to any one of claims 1 to 3, wherein the acrylic polymer (P1) has a hydroxyl value of 10 mgKOH / g or more.

5. The curable composition according to any one of claims 1 to 4, further comprising particles (G) that impart antiglare properties.

6. The curable composition according to claim 5 , wherein the particles (G) that impart antiglare properties are organic particles.

7. The curable composition according to any one of claims 1 to 6, further comprising inorganic fine particles (S).

8. A cured product comprising the curable composition according to any one of claims 1 to 7.

9. A laminate comprising a substrate layer and a layer comprising the cured product according to claim 8.

10. The laminate according to claim 9, wherein the substrate layer comprises at least one selected from the group consisting of triacetyl cellulose, (meth)acrylic, polyethylene terephthalate, and cyclic polyolefin.

11. The laminate according to claim 9 or 10, which has a surface functional layer on the cured product.

12. A polarizer protective film comprising the laminate according to claim 11.

13. A polarizing plate obtained by laminating the surface of the polarizer protective film according to claim 12 that does not have the hard coat layer to a polarizer.

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