TWI850326B - Curable composition for glare proof hard coating - Google Patents

Abstract

The present invention provides a material for forming a hard coating layer that has excellent anti-glare and scratch resistance and exhibits high initial water repellency. The present invention provides a curable composition and a hard coating film having a hard coating layer formed of the curable composition. The curable composition comprises (a) 100 parts by weight of an active energy ray-curable multifunctional monomer, (b) 0.05 to 10 parts by weight of a perfluoropolyether containing a poly(oxyperfluoroalkylene) group, wherein both ends of the molecular chain of the perfluoropolyether have an active energy ray polymerizable group through a urethane bond (but excluding a perfluoropolyether having a poly(oxyperfluoroalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond), (c) 5 to 40 parts by weight of microparticles having an average particle size of 0.2 μm to 15 μm, and (d) 1 to 20 parts by weight of a polymerization initiator that generates free radicals by active energy rays.

Description

Curable composition for anti-glare hard coating

The present invention relates to a curable composition useful as a material for forming a hard coating layer on the surface of various display elements such as touch panels and liquid crystal displays, and more particularly to a curable composition capable of forming a hard coating layer having excellent scratch resistance and anti-glare properties (anti-glare function) and also excellent initial water repellency.

Products equipped with touch panels such as personal computers, mobile phones, portable game consoles, and ATMs have been commercialized in large quantities. In particular, due to the launch of smart phones and touch panel PCs, the number of electrostatic capacitive touch panels with touch functions has exploded.

In order to prevent the visibility of the touch panel display from being reduced due to the reflection of external light into the screen, a method of laminating an anti-glare hard coating film having a hard coating layer with a surface roughness of several μm is used. As a method of forming roughness on the surface, a method of containing microparticles with a particle size of several μm in the hard coating layer is generally used.

However, electrostatic capacitive touch panels are operated by touching with human fingers. Therefore, there is a risk that fingerprints will be attached to the surface of the touch panel every time an operation is performed, which may significantly damage the image visibility of the display or the appearance of the display. Fingerprints contain moisture from sweat and oil from sebum. In order to make it difficult for these to adhere, it is strongly desired to give the hard coating layer on the surface of the display water repellency and oil repellency. However, since electrostatic capacitive touch panels are touched by people every day, even if the initial anti-fouling property reaches a considerable level, there are many cases where scratches are generated during use, which reduces the image visibility and anti-fouling function of the display. Especially for the anti-glare hard coating, since its surface is uneven, it is easy to get stuck and scratched. Therefore, the durability of anti-fouling during use is a problem.

So far, a hard coating having anti-glare and scratch resistance has been disclosed, in which a surface modifier having a poly(oxyperfluoroalkylene) structure and a (meth)acrylic group in the molecule is used as a component for imparting anti-fouling and scratch resistance to the hard coating surface, and a technology for using methyl methacrylate-styrene copolymer (MS) resin microparticles as a component for imparting anti-glare to the hard coating (Patent Document 1). On the other hand, a technology for using polymethyl methacrylate particles as a component for imparting anti-glare to the hard coating using a perfluoropolyether having an active energy line polymerizable group via a urethane bond at both ends of the molecular chain containing a poly(oxyperfluoroalkylene) group as a surface modifier is disclosed (Patent Document 2). [Prior Technical Document] [Patent Document]

[Patent Document 1] Japanese Patent Publication No. 2013-257359 [Patent Document 2] International Publication No. 2016/163478

[Problems to be solved by the invention]

The method specifically described in Patent Document 1 has a low fluorine content in the surface modifier having a poly(oxyperfluoroalkylene) structure and a (meth)acrylic group in the molecule, and there is a problem that sufficient antifouling and scratch resistance cannot be obtained. In addition, when the amount of MS resin particles added is reduced in order to obtain scratch resistance, there is a problem that sufficient antiglare properties cannot be obtained, and when MS resin particles are added to a level that obtains sufficient antiglare properties, there is a problem that the scratch resistance is significantly reduced. Furthermore, the resin particles in the hard coating layer have poor dispersibility, and there is also a problem that the resin particles become agglomerates and damage the appearance of the coating. Furthermore, the method specifically described in Patent Document 2 achieves scratch resistance and sufficient anti-glare properties, but the initial water contact angle is insufficient and there is a problem of low water repellency. That is, a hard coating layer having excellent anti-glare and scratch resistance and exhibiting high initial water repellency is sought. [Means for solving the problem]

As a result of repeated and active studies to achieve the above-mentioned purpose, the inventors of the present invention have found that by using a perfluoropolyether containing a poly(oxyperfluoroalkylene) group, and a perfluoropolyether having an active energy line polymerizable group interposed by a urethane bond instead of a poly(oxyalkylene) group at both ends of the molecular chain as a fluorine-based surface modifier, and then adding a curable composition containing microparticles, a hard coating layer having excellent anti-glare properties, high abrasion resistance and high initial water repellency can be formed, thereby completing the present invention.

That is, the first aspect of the present invention is related to a curable composition, which comprises (a) 100 parts by weight of an active energy ray-curable multifunctional monomer, (b) 0.05 to 10 parts by weight of a perfluoropolyether containing a poly(oxyperfluoroalkylene) group, the molecular chain of which has an active energy ray-polymerizable group via a urethane bond at both ends (but excluding a perfluoropolyether having a poly(oxyperfluoroalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond), (c) 5 to 40 parts by weight of microparticles having an average particle size of 0.2 μm to 15 μm, and (d) 1 to 20 parts by weight of a polymerization initiator that generates free radicals by active energy rays. As a second aspect, the curable composition related to the first aspect, wherein the perfluoropolyether (b) has at least two active energy ray polymerizable groups via urethane bonds at both ends of its molecular chain. As a third aspect, the curable composition related to the second aspect, wherein the perfluoropolyether (b) has at least three active energy ray polymerizable groups via urethane bonds at both ends of its molecular chain. As a fourth aspect, the curable composition related to any one of the first to third aspects, wherein the poly(oxyperfluoroalkylene) group has both repeating units -[OCF ₂ ]- and repeating units -[OCF ₂ CF ₂ ]-, and the repeating units are groups bonded by block bonding, random bonding, or block bonding and random bonding. As a fifth aspect, there is provided a curable composition related to the fourth aspect, wherein the perfluoropolyether (b) has a partial structure represented by the following formula [1]: (In the above formula [1], n represents the total number of the number of repeating units -[OCF ₂ CF ₂ ]- and the number of repeating units -[OCF ₂ ]- and is an integer from 5 to 30, and the repeating units -[OCF ₂ CF ₂ ]- and the repeating units -[OCF ₂ ]- are bonded by block bonding, random bonding, or any one of block bonding and random bonding.) As a sixth aspect, the curable composition according to any one of the first to fifth aspects, wherein the microparticles of the component (c) are organic microparticles. As a seventh aspect, the curable composition according to the sixth aspect, wherein the organic microparticles of the component (c) are polymethyl methacrylate microparticles. As an eighth aspect, it is related to the curable composition of any one of the first to seventh aspects, which further contains (e) a solvent. As a ninth aspect, it is related to a cured film obtained from the curable composition of any one of the first to eighth aspects. As a tenth aspect, it is related to a hard coating film, which is a hard coating film having a hard coating layer on at least one side of a film substrate, and the hard coating layer is formed by the cured film of the ninth aspect. As an eleventh aspect, it is related to the hard coating film of the tenth aspect, wherein the hard coating layer has a layer thickness of 1 μm to 20 μm. As a twelfth aspect, it is related to the hard coating film of the eleventh aspect, wherein the hard coating layer has a layer thickness of 3 μm to 15 μm. As a 13th aspect, it is a method for manufacturing a hard coating film, which is a method for manufacturing a hard coating film having a hard coating layer on at least one side of a film substrate, and the hard coating layer is obtained by the following steps: a step of applying a curable composition of any one of the 1st aspect to the 8th aspect on the film substrate to form a coating film, and a step of irradiating the coating film with active energy rays to cure it. As a 14th aspect, it is a display, which has a hard coating film of any one of the 10th aspect to the 12th aspect. As a 15th aspect, it is a polarizing plate, which has a hard coating film of any one of the 10th aspect to the 12th aspect. [Effect of the invention]

According to the present invention, a curable composition can be provided, which can be used to form a film having a thickness of about 1 μm to 20 μm, which not only has excellent scratch resistance and high anti-glare properties and excellent appearance, but also exhibits high initial water repellency. According to the present invention, a hard coating film having a hard coating layer formed by a hard coating film obtained from the above-mentioned curable composition or formed thereby on the surface can be provided, and a hard coating film having excellent anti-glare properties and appearance and excellent initial water repellency can be provided.

＜Hardening composition＞

The curable composition of the present invention is specifically related to a curable composition, which comprises (a) 100 parts by weight of an active energy ray-curable multifunctional monomer, (b) 0.05 to 10 parts by weight of a perfluoropolyether containing a poly(oxyperfluoroalkylene) group, the molecular chain of which has an active energy ray polymerizable group via a urethane bond at both ends (but excluding a perfluoropolyether having a poly(oxyperfluoroalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond), (c) 5 to 40 parts by weight of microparticles having an average particle size of 0.2 μm to 15 μm, and (d) 1 to 20 parts by weight of a polymerization initiator that generates free radicals by active energy rays. Below, each of the above components (a) to (e) will be described first.

[(a) Active energy ray-curable multifunctional monomer] The so-called active energy ray-curable multifunctional monomer refers to a monomer that undergoes a polymerization reaction and cures by irradiating active energy rays such as ultraviolet rays. In the curable composition of the present invention, a preferred (a) active energy ray-curable multifunctional monomer is, for example, a monomer selected from the group consisting of multifunctional (meth)acrylate compounds. In addition, the so-called (meth)acrylate compound in the present invention means both an acrylate compound and a methacrylate compound. For example, (meth)acrylic acid refers to acrylic acid and methacrylic acid.

Examples of the polyfunctional (meth)acrylate compound include trihydroxymethylpropane tri(meth)acrylate, di(trihydroxymethylpropane) tetra(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, glycerol tri(meth)acrylate, ethoxylated trihydroxymethylpropane tri(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, ethoxylated dipentaerythritol hexa(meth)acrylate, ethoxylated glycerol tri(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, 1,3-propylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, (Meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, bis(2-hydroxyethyl)isocyanurate di(meth)acrylate, tris(2-hydroxyethyl)isocyanurate tri(meth)acrylate, tricyclo[5.2.1.0 ^2,6 ] decanedimethanol di(meth)acrylate, dioxanediol di(meth)acrylate, 2-hydroxy-1-acryloyloxy-3-methacryloyloxypropane, 2-hydroxy-1,3-di(meth)acryloyloxypropane, 9,9-bis[4-(2-(meth)acryloxyethoxy)phenyl]fluorene, bis[4-(meth)acryloylthiophenyl]sulfide, bis[2-(meth)acryloylthioethyl]sulfide, 1,3-adamantanediol di(meth)acrylate, 1,3-adamantanedimethanol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate. Preferred multifunctional (meth)acrylate compounds include pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, and dipentaerythritol hexa(meth)acrylate.

In addition, as a multifunctional (meth)acrylate compound, a multifunctional urethane (meth)acrylate compound can be exemplified. The above-mentioned multifunctional urethane (meth)acrylate compound is a compound having multiple acryloyl groups or methacryloyl groups in one molecule and having one or more urethane bonds (-NHCOO-). As the above-mentioned multifunctional urethane (meth)acrylate compound, for example, a compound obtained by reacting a multifunctional isocyanate with a (meth)acrylate having a hydroxyl group, and a compound obtained by reacting a multifunctional isocyanate with a (meth)acrylate having a hydroxyl group and a polyol, but the multifunctional urethane (meth)acrylate compound that can be used in the present invention is not limited to the exemplified ones.

Examples of the above-mentioned multifunctional isocyanates include toluene diisocyanate, isophorone diisocyanate, xylene diisocyanate, and hexamethylene diisocyanate. Another example of the above-mentioned (meth)acrylate having a hydroxyl group includes 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, tripentaerythritol hepta(meth)acrylate, etc. Examples of the polyols include glycols such as ethylene glycol, propylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, and dipropylene glycol; polyester polyols obtained by reacting these glycols with aliphatic dicarboxylic acids or carboxylic anhydrides such as succinic acid, maleic acid, and adipic acid; polyether polyols; and polycarbonate diols.

In the present invention, as the above-mentioned (a) active energy ray-curable multifunctional monomer, one selected from the group consisting of the above-mentioned multifunctional (meth)acrylate compounds (compounds not containing urethane bonds) and the above-mentioned multifunctional urethane (meth)acrylate compounds can be used alone or in combination of two or more. From the viewpoint of the abrasion resistance of the obtained hardened material, it is preferred to use a multifunctional (meth)acrylate compound (compounds not containing urethane bonds) and a multifunctional urethane (meth)acrylate compound. In addition, as the above-mentioned multifunctional (meth)acrylate compound, it is preferred to use a multifunctional (meth)acrylate compound having more than five functions and a multifunctional (meth)acrylate compound having less than four functions (in this case, regardless of the presence or absence of urethane bonds, the same applies below). Furthermore, when the above-mentioned multifunctional (meth)acrylate compound (compound without urethane bond) and the above-mentioned multifunctional urethane (meth)acrylate compound are used in combination, the multifunctional urethane (meth)acrylate compound is preferably used in an amount of 20 to 100 parts by mass, and more preferably 30 to 70 parts by mass, relative to 100 parts by mass of the multifunctional (meth)acrylate compound (compound without urethane bond). Furthermore, among the above-mentioned multifunctional (meth)acrylate compounds, when the above-mentioned multifunctional (meth)acrylate compounds with more than five functions and the above-mentioned multifunctional (meth)acrylate compounds with less than four functions are used in combination, the multifunctional (meth)acrylate compounds with less than four functions are preferably used in an amount of 10 to 100 parts by mass, and more preferably 20 to 60 parts by mass, relative to 100 parts by mass of the multifunctional (meth)acrylate compounds with more than five functions. Furthermore, it is preferred that the multifunctional urethane (meth)acrylate compound is used in an amount of 20 to 100 parts by mass relative to 100 parts by mass of the multifunctional (meth)acrylate compound (compounds not containing urethane bonds), and that the multifunctional (meth)acrylate compound is used in an amount of 10 to 100 parts by mass relative to 100 parts by mass of the multifunctional (meth)acrylate compound having more than 5 functions, and that the multifunctional (meth)acrylate compound having less than 4 functions is used. It is preferred that the multifunctional urethane (meth)acrylate compound is used in an amount of 20 to 100 parts by mass relative to 100 parts by mass of the multifunctional (meth)acrylate compound (compounds not containing urethane bonds), and that the multifunctional (meth)acrylate compound is used in an amount of 20 to 60 parts by mass relative to 100 parts by mass of the multifunctional (meth)acrylate compound having more than 5 functions, and that the multifunctional (meth)acrylate compound having less than 4 functions is used. Parts by weight, Relative to 100 parts by weight of the multifunctional (meth)acrylate compound (compounds without urethane bonds), 30 to 70 parts by weight of the multifunctional urethane (meth)acrylate compound is used, and relative to 100 parts by weight of the multifunctional (meth)acrylate compound with more than 5 functions, 10 to 100 parts by weight of the multifunctional (meth)acrylate compound with less than 4 functions is used, Relative to 100 parts by weight of the multifunctional (meth)acrylate compound (compounds without urethane bonds), 30 to 70 parts by weight of the multifunctional urethane (meth)acrylate compound is used, and relative to 100 parts by weight of the multifunctional (meth)acrylate compound with more than 5 functions, 20 to 60 parts by weight of the multifunctional (meth)acrylate compound with less than 4 functions is used.

[(b) Perfluoropolyether containing poly(oxyperfluoroalkylene) groups, having active energy ray polymerizable groups via urethane bonds at both ends of the molecular chain (but excluding perfluoropolyethers having poly(oxyperfluoroalkylene) groups between the aforementioned poly(oxyperfluoroalkylene) groups and the aforementioned urethane bonds)] In the present invention, perfluoropolyether containing poly(oxyperfluoroalkylene) groups is used as component (b), which is a perfluoropolyether having active energy ray polymerizable groups via urethane bonds instead of poly(oxyalkylene) groups at both ends of the molecular chain (hereinafter also referred to as "(b) perfluoropolyether having polymerizable groups at both ends of the molecular chain"). Component (b) acts as a surface modifier in the hard coating layer of the curable composition to which the present invention is applied. In addition, the compatibility of component (b) and component (a) is excellent, thereby suppressing the generation of white turbidity in the hard coating layer and forming a hard coating layer with a transparent appearance. In addition, the above-mentioned poly(oxyalkylene) group is intended to mean a group in which the number of repeating units of the oxyalkylene group is 2 or more and the alkylene group in the oxyalkylene group is an unsubstituted alkylene group.

The carbon number of the alkylene group in the poly(oxyperfluoroalkylene) group is not particularly limited, but preferably has 1 to 4 carbon atoms. That is, the poly(oxyperfluoroalkylene) group refers to a group having a structure in which a divalent fluorocarbon group having 1 to 4 carbon atoms and an oxygen atom are alternately linked, and the oxyperfluoroalkylene group refers to a group having a structure in which a divalent fluorocarbon group having 1 to 4 carbon atoms and an oxygen atom are linked. Specific examples include -[OCF ₂ ]-(oxyperfluoromethylene), -[OCF ₂ CF ₂ ]-(oxyperfluoroethylene), -[OCF ₂ CF ₂ CF ₂ ]-(oxyperfluoropropane-1,3-diyl), -[OCF ₂ C(CF ₃ )F]-(oxyperfluoropropane-1,2-diyl) and the like. The above-mentioned oxyperfluoroalkylene groups may be used alone or in combination of two or more. In this case, the bonding of the plural oxyperfluoroalkylene groups may be either block bonding or random bonding.

Among them, from the viewpoint of obtaining a cured film with good abrasion resistance, a group having both -[OCF ₂ ]-(oxyperfluoromethylene) and -[OCF ₂ CF ₂ ]-(oxyperfluoroethylene) as repeating units is preferably used as the poly(oxyperfluoroalkylene) group. The poly(oxyperfluoroalkylene) group is preferably a group having a repeating unit of -[OCF ₂ ]- and -[OCF ₂ CF ₂ ]- in a ratio of [repeat unit: -[OCF ₂ ]-]:[repeat unit: -[OCF ₂ CF ₂ ]-]=2:1 to 1:2 in terms of molar ratio. A group containing these groups in a ratio of about 1:1 is more preferred. The bonding of these repeating units may be either block bonding or random bonding. The total number of repeating units of the oxyperfluoroalkylene group is preferably in the range of 5 to 30, more preferably in the range of 7 to 21. The weight average molecular weight (Mw) of the poly(oxyperfluoroalkylene) group measured by gel permeation chromatography in terms of polystyrene is 1,000 to 5,000, preferably 1,500 to 3,000.

Examples of the active energy ray polymerizable group include a (meth)acryl group and a vinyl group.

(b) The perfluoropolyether having polymerizable groups at both ends of the molecular chain is not limited to one having one active energy ray polymerizable group such as a (meth)acryl group at both ends of the molecular chain, and may also be one having two or more active energy ray polymerizable groups at both ends of the molecular chain. For example, examples of terminal structures containing active energy ray polymerizable groups include structures of formulas [A1] to [A5] shown below, and structures in which the acryl group in these structures is substituted with a methacryl group.

Examples of such (b) perfluoropolyethers having polymerizable groups at both ends of the molecular chain include compounds represented by the following formula [2]. (In formula [2], A represents the structures represented by the aforementioned formulas [A1] to [A5] and any one of the structures in which the acryl group in these structures is substituted with a methacryl group, PFPE represents the aforementioned poly(oxyperfluoroalkylene) group (but the side directly bonded to ^L1 is the oxy terminal, and the side bonded to the oxygen atom is the perfluoroalkylene terminal), ^L1 represents an alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms, m independently represents an integer of 1 to 5, and ^L2 represents an m+1 valent residue obtained by removing OH from an m+1 valent alcohol).

Examples of the alkylene group having 2 or 3 carbon atoms substituted with 1 _to 3 fluorine atoms include _-CH2CHF- , _{-CH2CF2- , -CHFCF2- , -CH2CH2CHF- , -CH2CH2CF2-} , _{and -CH2CHFCF2- , preferably -CH2CF2- .}

Examples of the partial structure (A-NHC(=O)O) _m L ² - in the compound represented by the above formula [2] include structures represented by the following formulas [B1] to [B12]. (In formula [B1] to formula [B12], A represents one of the structures represented by the aforementioned formula [A1] to formula [A5] and the structures in which the acryl group in these structures is substituted with a methacryl group.) In the structures represented by the aforementioned formula [B1] to formula [B12], formula [B1] and formula [B2] are equivalent to the case where m=1, formula [B3] to formula [B6] are equivalent to the case where m=2, formula [B7] to formula [B9] are equivalent to the case where m=3, and formula [B10] to formula [B12] are equivalent to the case where m=5. Among these, the structure represented by formula [B3] is preferred, and the combination of formula [B3] and formula [A3] is particularly preferred.

Particularly preferred perfluoropolyethers (b) having polymerizable groups at both ends of the molecular chain include compounds having a partial structure represented by the following formula [1]. The partial structure represented by formula [1] is equivalent to the part in which A-NHC(=O) is removed from the compound represented by formula [2]. In formula [1], n represents the total number of the repeating unit -[OCF ₂ CF ₂ ]- and the number of the repeating unit -[OCF ₂ ]- and is an integer in the range of 5 to 30, preferably an integer in the range of 7 to 21. In addition, the ratio of the number of the repeating unit -[OCF ₂ CF ₂ ]- to the number of the repeating unit -[OCF ₂ ]- is preferably in the range of 2:1 to 1:2, more preferably in the range of about 1:1. The bonding of the repeating units may be either block bonding or random bonding.

In the present invention, (b) the perfluoropolyether having polymerizable groups at both ends of the molecular chain is used in a ratio of 0.05 to 10 parts by mass, for example, 0.1 to 10 parts by mass, preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the aforementioned (a) active energy ray-curable multifunctional monomer. By using (b) the perfluoropolyether having polymerizable groups at both ends of the molecular chain in a ratio of 0.05 parts by mass or more, sufficient scratch resistance can be imparted to the hard coating. In addition, by using (b) the perfluoropolyether having polymerizable groups at both ends of the molecular chain in a ratio of 10 parts by mass or less, it can be fully compatible with (a) the active energy ray-curable multifunctional monomer, and a hard coating with less whiteness can be obtained.

The perfluoropolyether (b) having polymerizable groups at both ends of the molecular chain can be prepared by making the following formula [3] The hydroxyl groups at both ends of the compound represented by (in formula [3], PFPE, ^L1 , ^L2 and m have the same meanings as those in formula [2]) react with an isocyanate compound having a polymerizable group, i.e., a compound having an isocyanate group bonded to a bond in the structures represented by formula [A1] to [A5] and structures in which the acryl group in these structures is substituted with a methacrylic group (e.g., 2-(meth)acryloyloxyethyl isocyanate, 1,1-bis((meth)acryloyloxymethyl)ethyl isocyanate), to form a urethane bond to obtain the compound.

In the curable composition of the present invention, in addition to (b) a perfluoropolyether containing a poly(oxyperfluoroalkylene) group and having an active energy ray polymerizable group via a urethane bond at both ends of the molecular chain (however, there is no poly(oxyperfluoroalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond), a perfluoropolyether containing a poly(oxyperfluoroalkylene) group and having an active energy ray polymerizable group at one end (one end) of the molecular chain via a urethane bond and the other end of the molecular chain may also contain a poly(oxyperfluoroalkylene) group. A perfluoropolyether having a hydroxyl group at its terminal (other terminal) (however, there is no poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond and between the poly(oxyperfluoroalkylene) group and the hydroxyl group), or a perfluoropolyether containing a poly(oxyperfluoroalkylene) group as represented by the above formula [3] and having hydroxyl groups at both terminals of the molecular chain (however, there is no poly(oxyalkylene) group between the poly(oxyperfluoroalkylene) group and the hydroxyl group) [a compound not having an active energy ray-polymerizable group].

[(c) Microparticles with an average particle size of 0.2μm to 15μm] In the curable composition of the present invention, microparticles with an average particle size of 0.2μm to 15μm (hereinafter also referred to as "(c) microparticles") make the surface of the hard coating layer formed by the curable composition into a concave-convex shape and impart anti-glare properties. In the present invention, organic microparticles, inorganic microparticles, and organic-inorganic composite microparticles can be used as the above-mentioned (c) microparticles. Among these microparticles, organic microparticles are preferably used from the perspective of transparency. Organic microparticles can also play a role in controlling the turbidity value of the hard coating layer by controlling the difference between their refractive index and the refractive index of the hard coating layer forming material, that is, the curable resin composition. The shape of the aforementioned (c) microparticles is not particularly limited, but can be, for example, beads or spherical particles, or can be in an irregular shape such as powder. However, spherical particles are preferred, spherical particles with an aspect ratio of 1.5 or less are more preferred, and true spherical particles are the most preferred.

Examples of the aforementioned organic microparticles include polymethyl methacrylate microparticles (PMMA microparticles), silica microparticles, polystyrene microparticles, polycarbonate microparticles, acrylic styrene microparticles, benzoguanidine microparticles, melamine microparticles, polyolefin microparticles, polyester microparticles, polyamide microparticles, polyimide microparticles, and polyvinyl fluoride microparticles. Such organic microparticles may be used alone or in combination of two or more. Among such organic microparticles, polymethyl methacrylate microparticles are preferably used.

The average particle size of the aforementioned (c) microparticles used in the present invention is in the range of 0.2μm to 15μm, preferably in the range of 1μm to 10μm, for example. The average particle size (μm) here is the 50% volume diameter (median diameter) measured by the laser diffraction and scattering method based on the Mie theory. When the average particle size of the aforementioned (c) microparticles is larger than the above numerical range, the image clarity of the display will be reduced. When it is smaller than the above numerical range, sufficient anti-glare properties cannot be obtained, and the problem of large deviations is likely to occur. In addition, the aforementioned (c) microparticles are not particularly limited in terms of their particle size distribution, but preferably monodispersed microparticles with uniform particle size. The aforementioned (c) microparticles are preferably microparticles having a refractive index difference of 0 to 0.20 with the refractive index of the cured product of the aforementioned (a) active energy ray-curable multifunctional monomer, and more preferably the aforementioned refractive index difference is 0 to 0.10. In addition, the aforementioned (c) microparticles are preferably selected such that their average particle size relative to the film thickness of the cured film obtained from the curable composition of the present invention described later is in the range of average particle size b/film thickness a = 0.1 to 1.0.

The organic microparticles may preferably be commercially available products, for example, Techpolymer (registered trademark) MBX series, Techpolymer SBX series, Techpolymer MSX series, Techpolymer SMX series, Techpolymer SSX series, Techpolymer BMX series, Techpolymer ABX series, Techpolymer ARX series, Techpolymer AFX series, Techpolymer MB series, Techpolymer MBP series, Techpolymer MB-C series, Techpolymer ACX series, Techpolymer ACP series [all manufactured by Sekisui Chemicals Co., Ltd.]; Tospearl (registered trademark) series [manufactured by Momentive Performance Materials Japan Co., Ltd.]; Epostar (registered trademark) series, Epostar MA series, Epostar ST series, Epostar MX series [all manufactured by Nippon Catalyst Co., Ltd.]; Opt beads (registered trademark) series [manufactured by Nissan Chemical Co., Ltd.]; Flow beads series [manufactured by Sumitomo Seika Co., Ltd.]; Toray Pearl (registered trademark) PPS, Toray Pearl PAI, Toray Pearl PES, Toray Pearl EP [manufactured by Toray Co., Ltd.]; 3M (registered trademark) Dyneon TF fine powder series [manufactured by 3M Co., Ltd.]; Chemisnow (registered trademark) MX series, Chemisnow MZ series, Chemisnow MR series, Chemisnow KMR series, Chemisnow KSR series, Chemisnow MP series, Chemisnow SX series, Chemisnow SGP series [manufactured by Soken Chemical Co., Ltd.]; Taftic (registered trademark) AR650 series, Taftic AR-750 series, Taftic FH-S series, Taftic A-20 series, Taftic YK series, Taftic ASF series, Taftic HU series, Taftic F series, Taftic C series, Taftic WS series [all manufactured by Toyobo Co., Ltd.]; Art Pearl (registered trademark) GR series, Art Pearl SE series, Art Pearl G series, Art Pearl GS series, Art Pearl J series, Art Pearl MF series, Art Pearl BE series [all manufactured by Negami Industries Co., Ltd.]; Shin-Etsu Silicon (registered trademark) KMP series [manufactured by Shin-Etsu Chemical Industries Co., Ltd.].

In the present invention, the (c) fine particles are used in a ratio of 5 to 40 parts by mass, for example 5 to 30 parts by mass, preferably 8 to 25 parts by mass, relative to 100 parts by mass of the (a) active energy ray-curable multifunctional monomer.

[(d) Polymerization initiator that generates free radicals by active energy rays] The preferred polymerization initiator that generates free radicals by active energy rays in the curable composition of the present invention (hereinafter also referred to as "(d) polymerization initiator") is a polymerization initiator that generates free radicals by active energy rays such as electron beams, ultraviolet rays, X-rays, etc., especially by ultraviolet irradiation. Examples of the above-mentioned (d) polymerization initiator include benzoins, phenanones; thioxonones, azoles, azides, diazos, o-quinone diazides, acylphosphine oxides, oxime esters, organic peroxides, benzophenones, dicoumarins, diimidazoles, titanocenes, thiols, hydrocarbon halides, trichloromethyltriazines, and anionic salts of iodonium salts, coronium salts, etc. These can be used alone or in combination of two or more. Among them, based on the viewpoints of transparency, surface curability, and film curability, phenanones are preferably used as (d) polymerization initiators in the present invention. By using phenanones, a cured film with improved scratch resistance can be obtained.

Examples of the phenanones include α-hydroxyphenanones such as 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, 2-hydroxy-1-(4-(2-hydroxyethoxy)phenyl)-2-methylpropane-1-one, and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropane-1-one; α-aminophenanones such as 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropane-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butane-1-one; 2,2-dimethoxy-1,2-diphenylethane-1-one; and methyl phenylglyoxylate.

In the present invention, the (d) polymerization initiator is used in a ratio of 1 to 20 parts by mass, preferably 2 to 10 parts by mass, based on 100 parts by mass of the (a) active energy ray-curable multifunctional monomer.

[(e) Solvent] The curable composition of the present invention may further include (e) solvent, and may be in the form of a varnish (film-forming material). As the above-mentioned solvent, it is sufficient to consider the workability during coating in the formation of the cured film (hard coating layer) described later, the drying property before and after curing, etc. Examples include aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, tetrahydronaphthalene, etc.; aliphatic or alicyclic hydrocarbons such as n-hexane, n-heptane, mineral spirits, cyclohexane, etc.; halides such as methyl chloride, methyl bromide, methyl iodide, dichloromethane, chloroform, carbon tetrachloride, trichloroethylene, perchloroethylene, o-dichlorobenzene, etc.; esters or ester ethers such as ethyl acetate, propyl acetate, butyl acetate, methoxybutyl acetate, methyl cellulose acetate, ethyl cellulose acetate, propylene glycol monomethyl ether acetate (PGMEA), etc.; diethyl ether, tetrahydrofuran (THF), 1,4-dioxane, methyl cellulose, ethyl cellulose, butyl cellulose, propylene glycol monomethyl ether (PGMEA), etc. Ethers such as propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, propylene glycol mono-isopropyl ether, propylene glycol mono-n-butyl ether, etc.; ketones such as acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), di-n-butyl ketone, cyclohexanone, etc.; alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol, 2-ethylhexanol, benzyl alcohol, ethylene glycol, etc.; amides such as N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), etc.; sulfoxides such as dimethyl sulfoxide (DMSO), etc., and a mixture of two or more of these solvents.

In order to control the dispersion of the aforementioned microparticles during drying after coating, a high boiling point solvent can also be used. Examples of such solvents include cyclohexyl acetate, propylene glycol diacetate, 1,3-butanediol diacetate, 1,4-butanediol diacetate, 1,6-hexanediol diacetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol methyl ether acetate, 3-methoxybutyl acetate, ethylene glycol, diethylene glycol, propylene glycol, 1,3-butanediol, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, tripropylene glycol monomethyl ether, tripropylene glycol monoethyl ether, tripropylene glycol monopropyl ether, tripropylene glycol monobutyl ether, 3-methoxybutanol, dipropylene glycol dimethyl ether, and dipropylene glycol-methylpropyl ether.

The amount of the (e) solvent used is not particularly limited, but is used, for example, at a solid concentration of 1 to 70 mass %, preferably 5 to 50 mass %, in the curable composition of the present invention. The solid concentration (also referred to as non-volatile concentration) herein refers to the content of solids (excluding the solvent component from all components) of the curable composition of the present invention relative to the total mass (total mass) of the aforementioned components (a) to (d) (and other additives as desired).

[Other additives] In addition, the curable composition of the present invention may be appropriately formulated with commonly used additives as needed, such as polymerization accelerators, polymerization inhibitors, photosensitizers, leveling agents, surfactants, adhesion enhancers, plasticizers, ultraviolet absorbers, light stabilizers, antioxidants, storage stabilizers, antistatic agents, inorganic fillers, pigments, and dyes, as long as the effects of the present invention are not impaired. In addition, inorganic microparticles such as titanium oxide may also be formulated for the purpose of suppressing the haze value of the cured film. Furthermore, for the purpose of improving the hardness or scratch resistance of the cured film, inorganic microparticles such as silicon dioxide (silicon oxide) and silicon dioxide (silicon oxide) having reactive groups such as active energy ray curable groups may be formulated. In addition, the inorganic microparticles as the above other additives may be nanoparticles with an average particle size of less than 0.2 μm.

<Cured film> The curable composition of the present invention is coated on a substrate to form a coating, and the coating is irradiated with active energy rays to polymerize (cure) to form a cured film. The cured film is also the object of the present invention. The hard coating layer in the hard coating film described later can be formed by the cured film. In this case, the aforementioned substrate may be, for example, various resins (polycarbonate, polymethacrylate, polystyrene, polyesters such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyurethane, thermoplastic polyurethane (TPU), polyolefin, polyamide, polyimide, epoxy resin, melamine resin, triacetyl cellulose (TAC), acrylonitrile-butadiene-styrene copolymer (ABS), acrylonitrile-styrene copolymer (AS), norbornene-based resins, etc.), metal, wood, paper, glass, slate. The substrates may be in the form of a plate, a film, or a three-dimensional molded body.

As the coating method on the aforementioned substrate, for example, cast coating, rotary coating, doctor blade coating, dip coating, roll coating, spray coating, rod coating, die nozzle coating, inkjet method, printing method (letterpress printing, gravure printing, lithography, screen printing, etc.) can be appropriately selected. Among these methods, letterpress printing, particularly flexographic printing, is desirable from the viewpoint of being able to utilize a roll-to-roll method and thin film coating properties. It is also preferred to filter the curable composition in advance using a filter having a pore size of about 0.2 μm, etc., before applying. During coating, a solvent may be further added to the curable composition as needed. As the solvent in this case, various solvents listed in the aforementioned [(e) Solvent] may be used. After the curable composition is coated on the substrate to form a coating, the coating is pre-dried to remove the solvent using a heating mechanism such as a heating plate or an oven as needed (solvent removal step). The preferred heating and drying conditions at this time are, for example, 40°C to 120°C for about 30 seconds to 10 minutes. After drying, the coating is cured by irradiating with active energy rays such as ultraviolet rays. Examples of active energy rays include ultraviolet rays, electron beams, and X-rays, and ultraviolet rays are particularly preferred. As the light source used for ultraviolet irradiation, for example, sunlight, chemical lamp, low-pressure mercury lamp, high-pressure mercury lamp, metal halogen lamp, xenon lamp, UV-LED can be used. Then, by post-baking, specifically, by heating using a heating mechanism such as a heating plate or an oven to complete the polymerization. In addition, the thickness of the formed cured film is usually 0.01μm to 50μm, for example, 0.05μm to 20μm, preferably 1μm to 20μm, and more preferably 3μm to 15μm after drying and curing.

<Hard coating film> Using the curable composition of the present invention, a hard coating film having a hard coating layer on at least one side (surface) of a film substrate can be manufactured. The hard coating film is also the object of the present invention, and the hard coating film can be preferably used to protect the surface of various display elements such as touch panels or liquid crystal displays.

The hard coating layer in the hard coating film of the present invention can be formed by a method comprising the following steps: a step of applying the aforementioned curable composition of the present invention on a film substrate to form a coating film, and a step of irradiating the coating film with active energy rays such as ultraviolet rays to cure the coating film. A method of manufacturing a hard coating film having a hard coating layer on at least one side (surface) of a film substrate comprising these steps is also the object of the present invention.

As the film substrate, various transparent resin films that can be used for optical purposes can be used among the substrates exemplified in the aforementioned <cured film>. Preferred examples of resin films include films of polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), polyurethane, thermoplastic polyurethane (TPU), polycarbonate, polymethacrylate, polystyrene, polyolefin, polyamide, polyimide, triacetyl cellulose (TAC), etc. In addition, the method of coating the curable composition on the film substrate (film formation step) and the method of irradiating the film with active energy rays (curing method) can use the method exemplified in the aforementioned <cured film>. In the case where the curable composition of the present invention contains a solvent (in the form of a varnish), after the coating film forming step, a step of drying the coating film to remove the solvent may be included as needed. In this case, the coating film drying method (solvent removal method) exemplified in the aforementioned <cured film> can be used. The thickness (film thickness) of the hard coating layer thus obtained is preferably set to a thickness of 1 to 10 times the average particle size of the aforementioned (c) microparticles. For example, the thickness of the aforementioned hard coating layer is preferably 1 μm to 20 μm, and more preferably 3 μm to 15 μm.

The hard coating film of the present invention can be used as a hard coating film for a display or a polarizing plate. The display and polarizing plate having the hard coating film are also the objects of the present invention. [Example]

The following examples are given to illustrate the present invention in more detail, but the present invention is not limited to the following examples. In addition, in the examples, the apparatus and conditions used for sample preparation and physical property analysis are as follows.

(1) Coating with a rod coater Device: Automatic film coater AB3125 manufactured by TQC Sheen Co. Rod 1: A-Bar OSP-42 manufactured by OSG System Products Co., Ltd., maximum mesh film thickness 42μm (equivalent to wire rod #16) Rod 2: A-Bar OSP-22 manufactured by OSG System Products Co., Ltd., maximum mesh film thickness 22μm (equivalent to wire rod #9) Rod 3: A-Bar OSP-42 manufactured by OSG System Products Co., Ltd., maximum mesh film thickness 42μm (equivalent to wire rod #9) OSP-52, maximum mesh film thickness 52μm (equivalent to wire rod #20) Coating speed: 4m/min (2) Oven Device: 2-layer dust-free oven (upper and lower type) PO-250-45-D manufactured by Tri-Meter Co., Ltd. (3) UV curing Device: CV-110QC-G manufactured by Heraeus Co., Ltd. Lamp: High-pressure mercury lamp H-bulb manufactured by Heraeus Co., Ltd. (4) Film thickness (layer thickness) Device: Digital length measuring machine Digimicro MH-15M + Counter TC-101 manufactured by Nikon Co., Ltd. (5) Gloss measurement Device: Konica Gloss meter GM-268Plus manufactured by Minolta Co., Ltd. Measurement angle: 60 degrees (6) Abrasion resistance test Device: TRIBOGEAR TYPE: 30H reciprocating wear tester manufactured by Shinto Scientific Co., Ltd. Scanning speed: 4,500 mm/min Scanning distance: 50 mm (7) Total light transmittance, turbidity Device: Turbidity meter NDH5000 manufactured by Nippon Denshoku Industries Co., Ltd. (8) Contact angle measurement Device: DropMaster DM-501 manufactured by Kyowa Interface Science Co., Ltd. Measurement temperature: 20°C

In addition, the abbreviations have the following meanings. PFPE1: A perfluoropolyether having two hydroxyl groups without intervening poly(oxyalkylene) groups at both ends of the molecular chain [Fomblin (registered trademark) T4 manufactured by Solvay Specialty Polymers] PFPE2: A perfluoropolyether having a hydroxyl group with intervening poly(oxyalkylene) groups (repeating units 8 or 9) at both ends of the molecular chain [Fluorolink manufactured by Solvay Specialty Polymers 5147X] BEI: 1,1-bis(acryloyloxymethyl)ethyl isocyanate [Showa Denko Co., Ltd., Currants (registered trademark) BEI] DOTDD: Dioctyltin dineodecanoate [Nitto Kasei Co., Ltd., Neostann (registered trademark) U-830] DBTDL: Dibutyltin dilaurate [Tokyo Chemical Industry Co., Ltd.] DPHA: Dipentaerythritol pentaacrylate/dipentaerythritol hexaacrylate mixture [Nippon Kayaku Co., Ltd., KAYALAD (registered trademark) DN-0075] PETA: Pentaerythritol triacrylate/pentaerythritol tetraacrylate mixture [Shin-Nakamura Chemical Industry Co., Ltd., NK ESTER A-TMM-3LM-N] UA: 6-functional aliphatic urethane acrylate oligomer [EBECRYL (registered trademark) 5129 manufactured by DAICEL ALLNEX (Co., Ltd.)] FP1: Cross-linked polymethyl methacrylate true spherical particles [Techpolymer (registered trademark) SSX-105 manufactured by Sekisui Chemicals (Co., Ltd., average particle size 5μm] FP2: Cross-linked polymethyl methacrylate true spherical particles [Techpolymer (registered trademark) SSX-108 manufactured by Sekisui Chemicals (Co., Ltd., average particle size 8μm] FP3: Cross-linked polymethyl methacrylate true spherical particles [Techpolymer (registered trademark) SSX-108 manufactured by Sekisui Chemicals (Co., Ltd., average particle size 8μm] SSX-110, average particle size 10μm] FP4: Cross-linked polymethyl methacrylate true spherical particles [Techpolymer (registered trademark) manufactured by Sekisui Chemicals Co., Ltd. SSX-103, average particle size 3μm] O2959: 2-Hydroxy-1-(4-(2-hydroxyethoxy)phenyl)-2-methylpropane-1-one [OMNIRAD (registered trademark) 2959 manufactured by IGM Resins Co., Ltd.] EPA: ethyl p-dimethylaminobenzoate [KAYACURE (registered trademark) EPA manufactured by Nippon Kayaku Co., Ltd.] PET: polyethylene terephthalate (PET) film with easy bonding on both sides [Lumirror (registered trademark) U403 manufactured by Toray Co., Ltd., thickness 100μm] TAC: cellulose triacetate (TAC) film with easy bonding on both sides [Fuji Film Co., Ltd. manufactured by Fuji Film Co., Ltd. Tac (registered trademark) TD80ULP, thickness 80μm] MEK: methyl ethyl ketone MIBK: methyl isobutyl ketone PGME: propylene glycol monomethyl ether

[Preparation Example 1] Preparation of perfluoropolyether (SM1) having 4 acryl groups at both ends of the molecular chain (without intervening poly(oxyalkylene) groups) and urethane bonds PFPE1 1.19g (0.5 mmol), BEI 0.52g (2.0 mmol), DOTDD 0.017g (0.01 times the total mass of PFPE1 and BEI) and MEK 1.67g were fed into a spiral tube. The mixture was stirred at room temperature (about 23°C) for 24 hours to obtain a 50% by mass MEK solution of the target compound SM1. The weight average molecular weight of the obtained SM1 measured by GPC in terms of polystyrene conversion: Mw was 3,000, and the dispersion: Mw (weight average molecular weight)/Mn (number average molecular weight) was 1.2.

[Preparation Example 2] Preparation of perfluoropolyether (SM2) with acryl groups at both ends of the molecular chain PFPE2 1.05 g (0.5 mmol), BEI 0.26 g (1.0 mmol), DBTDL 0.01 g (0.02 mmol) and MEK 1.30 g were fed into a spiral tube. The mixture was stirred at room temperature (about 23°C) for 24 hours using a stirrer. The reaction mixture was diluted with MEK 3.93 g to obtain a 20 mass% MEK solution of the target compound SM2.

[Example 1 to Example 9, Comparative Example 1 to Comparative Example 4] Mix the following components according to Table 1 to prepare a curable composition with a solid content concentration of 40% by mass. In addition, the solid content here refers to the components other than the solvent. In Table 1, "parts" means "parts by mass" and "%" means "% by mass". (1) Multifunctional monomer: 50 parts by mass of DPHA, 30 parts by mass of UA and 20 parts by mass of PETA (2) Surface modifier: The surface modifier listed in Table 1 is in the amount listed in Table 1 (converted into solid content or active ingredient) (3) Organic microparticles: The organic microparticles listed in Table 1 are in the amount listed in Table 1 (4) Polymerization initiator: 5 parts by mass of O2959 (5) Polymerization accelerator: EPA is in the amount listed in Table 1 (6) Solvent: The solvent listed in Table 1 is in the amount listed in Table 1 The curable composition is applied to the film listed in Table 2 of A4 size by a rod applicator using the rod listed in Table 2 to obtain a coating film. The coating film is dried in an oven under the conditions listed in Table 2 to remove the solvent. The obtained film was exposed to UV light in a nitrogen atmosphere at an exposure amount shown in Table 2, thereby producing a hard coating film having a hard coating layer (cured film) with a thickness shown in Table 2.

The obtained hard coating film was evaluated for anti-glare, scratch resistance, water contact angle, turbidity and total light transmittance. The evaluation order of anti-glare, scratch resistance and water contact angle is shown below. The results are also shown in Table 3. [Anti-glare] The obtained hard coating film was covered on a black table with a gloss Gs (60°) of 11.8, and the gloss Gs (60°) of the hard coating layer surface of the hard coating film was measured and evaluated according to the following standards A, B and C. It is also assumed that in the case of actual use as a hard coating layer, at least B is required and A is expected. A: Gs(60°)≦120 B: 120＜Gs(60°)≦125 C: Gs(60°)＞125 [Abrasion resistance] A steel sponge [Liberon #0000 manufactured by Liberon] installed in the aforementioned reciprocating wear tester was used to apply a load of 500g/ ^cm2 to the hard coating surface of the hard coating film and rubbed back and forth 2,000 times. The degree of scratches was visually confirmed under a three-color light source and evaluated according to the following criteria A, B, and C. It is also assumed that in the case of actual use as a hard coating, at least B is required and A is expected. A: No scratches B: Several fine scratches C: All scratches [Contact angle] 1μL of water is attached to the surface of the hard coating layer of the hard coating film, and the contact angle θ is measured at 5 points after 5 seconds. The average value is set as the water contact angle, and the evaluation is performed according to the following standards A and C. It is also assumed that in the case of actual use as a hard coating, the water contact angle (initial water repellency) is required to be A (above 108°). A: Water contact angle value ≧108° C: Water contact angle value <108°

As shown in Tables 1 to 3, the hard coating films prepared by hard coating layers of Examples 1 to 9 using a hard coating layer having a perfluoropolyether SM1 having four acryl groups at both ends of the molecular chain (without intervening poly(oxyalkylene) groups) and intervening urethane bonds and organic microparticles as a surface modifier can obtain hard coating films having a layer thickness of 10 μm to 14 μm and excellent scratch resistance and anti-glare properties. The initial water repellency is also 108° or more, which fully meets the standard in actual use compared with the comparative examples described later.

On the other hand, the hard coating film of Comparative Example 1, which has a hard coating layer made of perfluoropolyether SM2 having an acryl group with a poly(oxyalkylene) group interposed at both ends of the molecular chain as a surface modifier, cannot obtain initial water repellency. And Comparative Examples 2 and 3, which do not contain organic microparticles, cannot obtain the desired anti-glare property. Furthermore, although Comparative Example 4 containing 50 parts by mass of organic microparticles obtains high anti-glare property, the scratch resistance is poor.

Claims (12)

A curable composition comprising (a) 100 parts by weight of an active energy ray-curable multifunctional monomer (excluding the component (b) below), (b) 0.05 to 10 parts by weight of a perfluoropolyether containing a poly(oxyperfluoroalkylene) group, wherein both ends of the molecular chain of the perfluoropolyether have an active energy ray polymerizable group through a urethane bond (but excluding a perfluoropolyether having a poly(oxyperfluoroalkylene) group between the poly(oxyperfluoroalkylene) group and the urethane bond), (c) 5 to 40 parts by weight of organic microparticles having an average particle size of 0.2 μm to 15 μm, and (d) 1 to 20 parts by weight of a polymerization initiator that generates free radicals by active energy rays, wherein the poly(oxyperfluoroalkylene) group has a repeating unit -[OCF ₂ ]- and a repeating unit -[OCF ₂ CF ₂ ]-, the repeating units are groups bonded by block bonding, random bonding, or block bonding and random bonding, the aforementioned (b) perfluoropolyether is a compound represented by the following formula [2],

(In formula [2], A represents the structures represented by the aforementioned formulas [A1] to [A5] and any one of the structures in which the acryl group in these structures is substituted with a methacryl group, PFPE represents the aforementioned poly(oxyperfluoroalkylene) group (however, the side directly bonded to ^L1 is an oxy group terminal, and the side bonded to an oxygen atom is a perfluoroalkylene terminal), ^L1 represents an alkylene group having 2 or 3 carbon atoms substituted with 1 to 3 fluorine atoms, and the partial structure (A-NHC(=O)O) _m ^L2- represents the structure represented by the following formula [B3])

The curable composition of claim 1, wherein the aforementioned (b) perfluoropolyether has at least 3 active energy ray polymerizable groups separated by urethane bonds at both ends of its molecular chain. The curable composition of claim 1 or 2, wherein in the compound represented by the aforementioned formula [2], in the aforementioned formula [2], A is a structure represented by the aforementioned formula [A3] or a structure in which the acryl group in such a structure is replaced by a methacryl group. As in claim 1, the curable composition, wherein the organic microparticles of the aforementioned component (c) are polymethyl methacrylate microparticles. The hardenable composition of claim 1 or 2 further comprises (e) a solvent. A hardened film obtained from a hardening composition as described in any one of claims 1 to 5. A hard coating film, which is a hard coating film having a hard coating layer on at least one side of a film substrate, wherein the hard coating layer is formed by a hardened film as described in claim 6. A hard coating film as claimed in claim 7, wherein the hard coating layer has a layer thickness of 1 μm to 20 μm. A hard coating film as claimed in claim 8, wherein the hard coating layer has a layer thickness of 3 μm to 15 μm. A method for manufacturing a hard coating film, which is a method for manufacturing a hard coating film having a hard coating layer on at least one side of a film substrate, wherein the hard coating layer is obtained by the following steps: a step of applying a curable composition as described in any one of claims 1 to 5 on the film substrate to form a coating film, and a step of irradiating the coating film with active energy rays to harden the coating film. A display having a hard coating film as described in any one of claims 7 to 9. A polarizing plate having a hard coating film as described in any one of claims 7 to 9.