JP7589764B2 - Curable composition, cured product and laminate - Google Patents

Description

The present invention relates to a curable composition, and a cured product and a laminate obtained by using the curable composition. More specifically, the present invention relates to a curable composition that has excellent storage stability, a high degree of freedom in coating conditions, and is capable of obtaining a cured product under various coating conditions, and that can obtain a laminate having excellent anti-blocking properties, transparency, recoating properties, scratch resistance, curl resistance, etc., and that can easily control the refractive index of the obtained cured product, as well as a cured product and a laminate of the curable composition, and a hard coat film.

A hard coating with excellent hardness and slipperiness may be applied to the surface of a thermoplastic resin film, such as a polyethylene terephthalate (PET) film. Films with such hard coatings may be wound into rolls during storage for the purposes of securing storage space, ease of handling during molding, and prevention of dirt. When a hard-coated film is wound into a roll, it is necessary to prevent blocking between the films.

As a method for preventing blocking of a film, a method is disclosed in which a hard coat layer is formed on the film surface, and organic fine particles having a specific particle size and a dispersant are blended into the hard coat layer to form irregularities on the surface of the hard coat layer (Patent Document 1). Also, a method is disclosed in which a hard coat layer is formed on the film surface, and a large amount of reactive fine particles are blended into the hard coat layer to form irregularities on the surface of the hard coat layer to prevent blocking (Patent Document 2). Also, a method is disclosed in which a resin composition for forming a hard coat layer is applied to a substrate, and then precipitated through phase separation in a drying process and an ultraviolet (UV) irradiation process to form irregularities on the surface of the hard coat layer to prevent blocking (Patent Document 3). Furthermore, a method is disclosed in which large irregularities are formed by using a hard coat layer formed of a polyfunctional polymerizable unsaturated compound, a radical polymerization initiator, monodispersed inorganic particles, a particle flocculant, etc. as the hard coat layer to be applied to the film surface (Patent Document 4).

Japanese Patent Application Publication No. 2013-75955 Japanese Patent Application Publication No. 2014-16608 Japanese Patent Application Publication No. 2013-209516 Japanese Patent Application Publication No. 2011-29175

Through detailed studies by the present inventors, it has been found that the techniques disclosed in the above Patent Documents 1 to 4 have the following problems. In the technique disclosed in Patent Document 1, the particles mixed have a large average primary particle diameter of 0.5 to 1.5 μm, and the internal haze increases, resulting in insufficient transparency. In the technique disclosed in Patent Document 2, the particles mixed are small, resulting in good transparency, but the technique contains a large amount of two types of particles with different shapes and reactive groups, resulting in poor storage stability. In the technique disclosed in Patent Document 3, particles such as inorganic particles are not essential, but the shape of the unevenness on the hard coat layer surface changes depending on the drying conditions and UV irradiation conditions, resulting in low flexibility in coating conditions. In the technique disclosed in Patent Document 4, the particle diameter of the aggregated particles is large, resulting in low transparency of the coating film.

Furthermore, various materials are usually laminated before and after the hard coat layer, which requires anti-blocking properties. In this case, adjusting the refractive index between each layer is important for various optical applications. For this reason, it is necessary to control the refractive index of the hard coat layer over a wide range without compromising the anti-blocking properties or transparency.

The present invention aims to solve these problems of the conventional technology. That is, the present invention aims to provide a curable composition that has excellent storage stability, has a high degree of freedom in coating conditions, can produce a cured product under various coating conditions, can produce a laminate that is excellent in anti-blocking properties, transparency, recoating properties, scratch resistance, curl resistance, etc., and can easily control the refractive index of the resulting cured product.

As a result of intensive research conducted by the present inventors in consideration of the above problems, it was found that a curable composition containing an ethylenically unsaturated compound and particles having a specific particle size, and in which the blending amounts of these are within a specific range, can solve the above problems. That is, the gist of the present invention is as follows: [1] to [17].

[1] A curable composition comprising the following components (A) and (B), wherein the component (B) is 0.01 to 150 parts by weight per 100 parts by weight of the component (A):
Component (A): A compound having an ethylenically unsaturated bond. Component (B): A group of particles having an average primary particle size of 1 to 100 nm and a d90 value of 100 to 2,000 nm as measured by a laser diffraction particle size distribution analyzer.

[2] The curable composition according to [1], wherein the value of [average primary particle size]/[d90] of component (B) is 0.01 to 0.40.
[3] The curable composition according to [1] or [2], wherein component (B) has a d10 of 10 to 500 nm and a d50 of 30 to 1,000 nm, as measured by a laser diffraction particle size distribution analyzer.
[4] The curable composition according to any one of [1] to [3], wherein the weight average molecular weight of component (A) is less than 2,100, and the composition contains the following component (C) in an amount of 0.01 to 20 parts by weight per 100 parts by weight of component (A):
Component (C): an organic polymer compound having a weight average molecular weight (Mw) of 2,100 to 200,000. [5] The curable composition according to [4], wherein the solubility parameter (SP value) of component (C) is 9.3 to 12.6.

[6] The curable composition according to [4] or [5], comprising a (meth)acrylic resin as component (C).
[7] The curable composition according to any one of [1] to [6], comprising a polyfunctional (meth)acrylate as component (A).
[8] The curable composition according to [7], wherein the polyfunctional (meth)acrylate comprises at least one selected from the group consisting of polyfunctional (meth)acrylates having a nitrogen atom-containing heterocyclic structure, polyfunctional (meth)acrylates having a dendrimer structure, and polyfunctional (meth)acrylates having a hyperbranched polymer structure, and the total content of the polyfunctional (meth)acrylates is 1 to 65% by weight based on the total weight of component (A).

[9] The curable composition according to any one of [1] to [8], which contains an organic solvent and has a solid content concentration of 5 to 95 wt %.
[10] The curable composition according to [9], wherein the organic solvent is at least one selected from the group consisting of saturated hydrocarbon solvents, ester solvents, ether solvents, alcohol solvents, and ketone solvents.
[11] The curable composition according to any one of [1] to [10], which contains a polymerization initiator and has a content of 0.01 to 20 parts by weight relative to 100 parts by weight of the component (A).

[12] A cured product obtained by irradiating the curable composition according to any one of [1] to [11] with active energy rays.
[13] A laminate having a substrate and a hard coat layer, the hard coat layer being a layer formed by applying the curable composition according to any one of claims [1] to [10] onto the substrate and irradiating the applied composition with active energy rays.
[14] The laminate according to [13], wherein the substrate is a plastic substrate.

[15] The laminate according to [14], wherein the plastic substrate is at least one selected from the group consisting of a polycarbonate resin, a polyethylene terephthalate resin, and a polymethyl methacrylate resin.
[16] A laminate having a substrate layer and a hard coat layer, the hard coat layer containing the following component (B), and having a haze value measured according to JIS K7136 (2000) of less than 0.6%:
Component (B): A group of particles having an average primary particle size of 1 to 100 nm and a d90 of 100 to 2,000 nm as measured by a laser diffraction particle size distribution meter. [17] A hard coat film comprising the following component (B) and having a content of 0.01 to 55% by weight based on the entire hard coat film:
Component (B): A group of particles having an average primary particle size of 1 to 100 nm and a d90 of 100 to 2,000 nm as measured by a laser diffraction particle size distribution analyzer.

According to the present invention, there is provided a curable composition that has excellent storage stability, has a high degree of freedom in coating conditions, can produce a cured product under various coating conditions, produces a laminate that is excellent in anti-blocking properties, transparency, recoating properties, scratch resistance, curl resistance, etc., and allows easy control of the refractive index of the resulting cured product. In addition, according to the present invention, there are provided a cured product and a laminate, as well as a hard coat film, obtained using this curable composition.

The following description is an example of an embodiment of the present invention, and the present invention is not limited to the following description as long as it does not deviate from the gist of the invention. In this specification, when the expression "~" is used, it is used as an expression including the numerical value or physical property value before and after it. In this invention, when the expression "(meth)acrylate" is used, it means one or both of "acrylate" and "methacrylate", and the same applies to the use of expressions such as "(meth)acryloyl" and "(meth)acrylic".

The curable composition of the present invention contains the following components (A) and (B), and contains 0.01 to 150 parts by weight of component (B) per 100 parts by weight of component (A).
Component (A): A compound having an ethylenically unsaturated bond. Component (B): A group of particles having an average primary particle size of 1 to 100 nm and a d90 value of 100 to 2,000 nm as measured by a laser diffraction particle size distribution analyzer.

[Component (A)]
The component (A) used in the present invention is a compound having an ethylenically unsaturated bond. The curable composition of the present invention is provided with curability and scratch resistance by containing the component (A).

The type of ethylenically unsaturated bond contained in the compound of component (A) is not particularly limited, but examples include (meth)acryloyl groups, (meth)acrylamide groups, styryl groups, allyl groups, etc. Among these, it is preferable that component (A) contains a compound having a (meth)acryloyl group. In component (A), the number of ethylenically unsaturated bonds in one molecule is not particularly limited, but is usually 1 to 15. Two or more compounds of component (A) having different numbers of ethylenically unsaturated bonds may be mixed and used.

Among the components (A), compounds having a (meth)acryloyl group include monofunctional (meth)acrylates having one (meth)acryloyl group and polyfunctional (meth)acrylates having two or more (meth)acryloyl groups. These can be used alone or in combination of two or more, but it is preferable to include a polyfunctional (meth)acrylate.

Examples of monofunctional (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, glycidyl (meth)acrylate, (meth)acryloylmorpholine, tetrahydrofurfuryl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isobornyl (meth)acrylate, isodecyl (meth)acrylate, and lauryl (meth)acrylate. acrylate, tridecyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, benzyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethyl carbitol (meth)acrylate, phosphate (meth)acrylate, ethylene oxide modified phosphate (meth)acrylate, phenoxy (meth)acrylate, ethylene oxide modified phenoxy (meth)acrylate, propylene oxide modified phenoxy (meth)acrylate, nonylphenol (meth)acrylate, ethylene oxide modified nonylphenoxy (meth)acrylate, propylene oxide modified nonylphenol (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hydrogen phthalate, 2-(meth)acryloyloxypropyl hexahydro Examples of the mono(meth)acrylates include hydrogen phthalate, 2-(meth)acryloyloxypropyl tetrahydrohydrogen phthalate, dimethylaminoethyl (meth)acrylate, trifluoroethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, hexafluoropropyl (meth)acrylate, octafluoropropyl (meth)acrylate, octafluoropropyl (meth)acrylate, and adamantane derivative mono(meth)acrylates such as adamantyl (meth)acrylate having a monovalent mono(meth)acrylate derived from 2-adamantane and adamantanediol. These may be used alone or in combination of two or more.

Examples of polyfunctional (meth)acrylates include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, butanediol di(meth)acrylate, hexanediol di(meth)acrylate, nonanediol di(meth)acrylate, ethoxylated hexanediol di(meth)acrylate, propoxylated hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, Bifunctional (meth)acrylates such as ethoxylated neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, and hydroxypivalic acid neopentyl glycol di(meth)acrylate; 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, Polyfunctional (meth)acrylates having three or more functional groups, such as propane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, ditrimethylolpropane penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and ditrimethylolpropane hexa(meth)acrylate; modified products of polyfunctional (meth)acrylate compounds in which a part of these (meth)acrylates is substituted with an alkyl group or ε-caprolactone; polyfunctional (meth)acrylates having an isocyanurate structure, such as tetra(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; modified products of polyfunctional (meth)acrylate compounds in which a part of these (meth)acrylates is substituted with an alkyl group or ε-caprolactone; Examples of such urethane (meth)acrylates include polyfunctional (meth)acrylates having a nitrogen atom-containing heterocyclic structure such as polyfunctional (meth)acrylates having a dendrimer structure and polyfunctional (meth)acrylates having a hyperbranched dendritic structure such as polyfunctional (meth)acrylates having a dendrimer structure and polyfunctional (meth)acrylates having a hyperbranched polymer structure; urethane (meth)acrylates in which a (meth)acrylate having a hydroxyl group is added to a diisocyanate or triisocyanate, and urethane (meth)acrylates in which a (meth)acrylate having a hydroxyl group is added to a reaction product having an isocyanate group at the end obtained by reacting an isocyanate compound with a diol compound. These may be used alone or in combination of two or more.

Among the polyfunctional (meth)acrylates that can be used as component (A), it is preferable to include at least one of a polyfunctional (meth)acrylate having a nitrogen atom-containing heterocyclic structure and a polyfunctional (meth)acrylate having a multi-branched dendritic structure. From the viewpoint of hardness, the total content of the polyfunctional (meth)acrylate having a nitrogen atom-containing heterocyclic structure and the polyfunctional (meth)acrylate having a multi-branched dendritic structure is preferably 65% by weight or less, more preferably 50% by weight or less, even more preferably 35% by weight or less, particularly preferably 20% by weight or less, and most preferably 10% by weight or less, based on the entire component (A). On the other hand, from the viewpoint of improving curl resistance, the total content of the polyfunctional (meth)acrylate having a nitrogen atom-containing heterocyclic structure and the polyfunctional (meth)acrylate having a multi-branched dendritic structure is preferably 1% by weight or more, more preferably 3% by weight or more, and even more preferably 5% by weight or more, based on the entire component (A).

As the polyfunctional (meth)acrylate having a nitrogen atom-containing heterocyclic structure, one in which a (meth)acryloyl group is linked to the nitrogen atom-containing heterocyclic structure directly or via a hydrocarbon group having 1 to 10 carbon atoms or an alkylene oxide structure having 1 to 10 carbon atoms is preferred, and specific examples include polyfunctional (meth)acrylates having an isocyanurate structure. Examples include isocyanuric acid ethylene oxide (EO) modified diacrylate (e.g., Aronix M-215 manufactured by Toagosei Co., Ltd.), ε-caprolactone modified tris(acryloxyethyl)isocyanurate (e.g., Aronix M-327, A-9300-1CL manufactured by Toagosei Co., Ltd.), isocyanuric acid EO modified di- and triacrylate (e.g., Aronix M-313, Aronix M-315, A-9300 manufactured by Toagosei Co., Ltd.), etc.

Examples of polyfunctional (meth)acrylates having a multi-branched dendritic structure include polyfunctional (meth)acrylates having a dendrimer structure and polyfunctional (meth)acrylates having a hyperbranched polymer structure. Polyfunctional (meth)acrylates having a dendrimer structure are compounds having a structure branched with high regularity, while polyfunctional (meth)acrylates having a hyperbranched polymer structure are compounds having a structure branched with low regularity, and have low viscosity and excellent solvent solubility compared to linear polymers. Examples of polyfunctional (meth)acrylates having a dendrimer structure include Viscoat #1000 manufactured by Osaka Organic Chemical Industry Co., Ltd. Examples of polyfunctional (meth)acrylates having a hyperbranched polymer structure include STAR-501, SIRIUS-501, SUBARU-501, and the like, all of which are manufactured by Osaka Organic Chemical Industry Co., Ltd.

From the viewpoint of improving the handling and coating properties of the curable composition, it is preferable that the weight average molecular weight (Mw) of component (A) is less than 2,100. From the viewpoint of improving this effect, it is preferable that the Mw of component (A) is 1,600 or less, and more preferably 1,100 or less. On the other hand, it is also possible to use as component (A) of the present invention a compound having a low molecular weight and in a range where the molecular weight is not usually measured as a weight average molecular weight. In component (A), the weight average molecular weight (molecular weight) of such a low molecular weight compound is usually 50 or more. The Mw of component (A) can be measured by gel permeation chromatography (GPC) as shown in the examples below.

[Component (B)]
The component (B) used in the present invention is a particle group having an average primary particle size of 1 to 100 nm and a d90 (particle size value at which the cumulative value is 90% in the results measured by a laser diffraction particle size distribution analyzer) of 100 to 2,000 nm, as measured by a laser diffraction particle size distribution analyzer. Here, the fact that d90 is in a predetermined range different from the value of the average primary particle size indicates that the component (B) is in the form of an aggregate. That is, in the component (B), particles having an average primary particle size in a specific range are present in a specific aggregated state. In the curable composition of the present invention, the component (B) mainly contributes to anti-blocking properties. It is presumed that the reason why the cured product and laminate obtained by using the curable composition of the present invention are particularly excellent in anti-blocking properties and transparency is that, since the component (B) has an average primary particle size in the above range but is in the form of a specific aggregate, when the curable composition is cured, the component (B) forms unevenness on the surface to express anti-blocking properties, while allowing sufficient light transmission.

From the viewpoint of anti-blocking properties of the coating film, the content of component (B) is 0.01 parts by weight or more, preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, even more preferably 2 parts by weight or more, and particularly preferably 3 parts by weight or more, relative to 100 parts by weight of component (A). On the other hand, from the viewpoint of transparency, the content of component (B) is 150 parts by weight or less, preferably 130 parts by weight or less, more preferably 110 parts by weight or less, even more preferably 90 parts by weight or less, particularly preferably 70 parts by weight or less, and most preferably 45 parts by weight or less, relative to 100 parts by weight of component (A).

Component (B) has an average primary particle size of 1 to 100 nm, and a d90 measured by a laser analysis type particle size distribution meter of 100 to 2,000 nm, which provides good anti-blocking properties and transparency. From the viewpoint of anti-blocking properties, the average primary particle size of component (B) is 1 nm or more, preferably 5 nm or more, more preferably 10 nm or more, even more preferably 20 nm or more, and most preferably 30 nm or more, while from the viewpoint of transparency, it is 100 nm or less, more preferably 75 nm or less, and even more preferably 50 nm or less. Also, from the viewpoint of anti-blocking properties, the d90 of component (B) is 100 nm or more, preferably 150 nm or more, more preferably 200 nm or more, even more preferably 250 nm or more, and particularly preferably 300 nm or more, while from the viewpoint of transparency, it is 2,000 nm or less, preferably 1,500 nm or less, and more preferably 1,000 nm or less. In particular, from the viewpoint of controlling the refractive index when the curable composition is cured, the d90 of component (B) is preferably 575 nm or less, more preferably 550 nm or less, even more preferably 525 nm or less, particularly preferably 500 nm or less, and most preferably 475 nm or less.

In addition, from the viewpoint of obtaining good antiblocking properties and transparency, it is preferable that the value of [average primary particle size]/[d90] of component (B) is 0.01 to 0.40. From this viewpoint, the value of [average primary particle size]/[d90] is more preferably 0.02 or more, more preferably 0.35 or less, even more preferably 0.30 or less, particularly preferably 0.25 or less, and most preferably 0.20 or less.

In addition, in terms of achieving both antiblocking properties and transparency, it is preferable that the particle diameter value (d10) at which the cumulative value becomes 10% and the particle diameter value (d50) at which the cumulative value becomes 50% are in the following ranges in the results measured by the laser analysis particle size distribution meter. That is, the d10 of component (B) is preferably 10 nm or more, more preferably 20 nm or more, even more preferably 30 nm or more, particularly preferably 40 nm or more, and most preferably 50 nm or more, while it is preferably 500 nm or less, more preferably 300 nm or less, even more preferably 200 nm or less, and particularly preferably 150 nm or less. In addition, the d50 of component (B) is preferably 30 nm or more, more preferably 50 nm or more, even more preferably 70 nm or more, and particularly preferably 90 nm or more, while it is preferably 1,000 nm or less, more preferably 750 nm or less, and even more preferably 500 nm or less.

The average primary particle diameter of component (B) is a value measured using a scanning electron microscope or a transmission electron microscope. When the primary particles of component (B) have a shape other than spherical, the average primary particle diameter is calculated as the average of the major axis diameter and the minor axis diameter. The particle diameter measured using a laser diffraction particle size distribution analyzer is specifically a value calculated using a Microtrack UPA (manufactured by Nikkiso Co., Ltd.).

Component (B) may have an average primary particle size and d90 within the above ranges, and the particle size may be adjusted by crushing aggregated particles, by generating aggregated particles using a sol-gel method or the like, or by aggregating dispersed particles using an aggregating agent to adjust the particle size.

The type of component (B) is not particularly limited as long as the average primary particle size and d90 satisfy the above ranges, and it may be any of inorganic particles, organic particles, and organic-inorganic composite particles. Only one type of these may be used, or two or more types may be used in combination. When the particles of component (B) are inorganic particles, they are preferred because the heat resistance and hardness tend to be high when made into a hard coat, and the anti-blocking properties tend to be better.

Examples of inorganic particles include oxide particles such as silica, alumina, titania, zirconia, zeolite, mica, synthetic mica, calcium oxide, zirconium oxide, zinc oxide, magnesium fluoride, smectite, synthetic smectite, vermiculite, ITO (indium oxide/tin oxide), ATO (antimony oxide/tin oxide), tin oxide, indium oxide, and antimony oxide. Among these, at least one oxide particle selected from the group consisting of silica, alumina, titania, zirconia, zinc oxide, magnesium fluoride, ITO, tin oxide, and antimony oxide is preferred, and oxide particles containing at least silica are more preferred.

Oxide particles containing silica are commercially available. Examples of such commercially available products include SIRMIBK15WT%-H58, SIRMIBK15WT%-M18, SIRMIBK15WT%-E83, SIRMIBK15WT%-M05, SIRMIBK15WT%-H84, SIRMIBK15WT%-H94, and SIRMIBK15 Examples include WT%-M36, SIRMIBK15WT%-M06, SIRMIBK15WT%-M44, SIRMIBK15WT%-M46, SIRMIBK15WT%-M42, SIRMIBK15WT%-M47, SIRMIBK15WT%-M61, SIRMIBK15WT%-M62, etc.

Specific examples of organic particles include organic cross-linked polymer particles, such as (meth)acrylic cross-linked polymer particles, styrene cross-linked polymer particles, urethane cross-linked polymer particles, polyester cross-linked polymer particles, silicone cross-linked polymer particles, polyimide cross-linked polymer particles, and fluorine cross-linked polymer particles. In particular, acrylic crosslinked polymer particles are preferred, and specific examples thereof include (meth)acrylic crosslinked polymer particles obtained by polymerization methods such as suspension polymerization, emulsion polymerization, soap-free emulsion polymerization, mini-emulsion polymerization, dispersion polymerization, seed polymerization, etc., of (meth)acrylic monofunctional monomers such as methyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate (herein, "(meth)acrylic monofunctional monomer" is a general term for (meth)acrylic acid monomers, (meth)acrylate monomers having one unsaturated double bond, and (meth)acrylamide monomers having one unsaturated double bond), and (meth)acrylic polyfunctional monomers such as trimethylolpropane tri(meth)acrylate, allyl (meth)acrylate, and ethylene glycol di(meth)acrylate (herein, "(meth)acrylic polyfunctional monomer" is a general term for (meth)acrylate monomers having two or more unsaturated double bonds, and (meth)acrylamide monomers having two or more unsaturated double bonds). In addition, the (meth)acrylic crosslinked particles may be styrene-(meth)acrylic crosslinked polymer particles in which a styrene-based monofunctional monomer such as styrene or α-methylstyrene, or a styrene-based polyfunctional monomer such as divinylbenzene is further copolymerized during polymerization.

Examples of organic-inorganic composite particles include particles having an organic polymer skeleton and a polysiloxane skeleton having an organosilicon in which a silicon atom is directly chemically bonded to at least one carbon atom in the skeleton, and particles in which a vinyl polymer is included in the structure of polysiloxane particles having (meth)acryloxy groups.

As long as the average primary particle size and d90 of component (B) satisfy the above ranges, the shape of the aggregated state is not particularly limited, and may be any shape, such as spherical, chain-like, needle-like, plate-like, scaly, crushed, bale-like, cocoon-like, or confetti-like. The shape of component (B) is preferably spherical or chain-like, and is particularly preferably spherical. When the shape of component (B) is spherical or chain-like, the uniformity of the antiblocking properties of the surface of the obtained cured product tends to be higher, and better antiblocking properties tend to be obtained.

The curable composition of the present invention may contain only one type of particle as component (B) as described above, or may contain two or more types.

[Component (C)]
From the viewpoint of further improving antiblocking properties and coating film appearance, the curable composition of the present invention preferably contains the following component (C).
Component (C): an organic polymer compound having a weight average molecular weight (Mw) of 2,100 to 200,000

By having the Mw of component (C) of 2,100 or more, it is possible to suppress the bleeding out of component (C) from the surface of the cured product after the curable composition is cured, and the antiblocking property also tends to be improved. From these viewpoints, the Mw of component (C) is preferably 2,200 or more, more preferably 2,300 or more, and even more preferably 2,400 or more. On the other hand, by having the Mw of component (C) of 200,000 or less, component (C) tends to segregate easily on the surface of the cured product when cured, and the antiblocking property tends to be better. From this viewpoint, the Mw of component (C) is preferably 150,000 or less, more preferably 100,000 or less, even more preferably 70,000 or less, and particularly preferably 40,000 or less. The Mw of the organic polymer compound of component (C) can be measured by gel permeation chromatography (GPC) as shown in the examples below.

In the present invention, it is preferable that the solubility parameter (SP value) of component (C) is 9.3 to 12.6. If the SP value is 9.3 or more, the compatibility with other components tends to be good, and if the SP value is 12.6 or less, the slipperiness of the cured surface when the curable composition is cured tends to be good and the antiblocking property tends to be better. From these viewpoints, the SP value is more preferably 9.4 or more, and even more preferably 9.5 or more, while it is more preferably 12.6 or less, even more preferably 12.0 or less, and particularly preferably 11.5 or less. The solubility parameter (SP value) is a Solubility Parameter. This SP value is a measure of solubility, and the larger the value, the higher the polarity, and conversely, the smaller the value, the lower the polarity. The solubility parameter (SP value) of component (C) is a value calculated by the method proposed by Fedors et al. Specifically, it can be found by referring to "POLYMER ENGINEERING AND SCIENCE, FEBRUARY, 1974, Vol. 14, No. 2, ROBERT F. FEDORS. (pages 147-154)".

In the present invention, it is preferable that the glass transition temperature (Tg) of component (C) is 35°C or less from the viewpoint of handleability since it can be handled in a liquid state. From this viewpoint, the glass transition temperature (Tg) is more preferably 25°C or less, even more preferably 15°C or less, and particularly preferably 0°C or less. On the other hand, the lower limit of the glass transition temperature is not particularly limited, but is usually -125°C. The glass transition temperature of component (C) can be measured according to JIS K7121 "Method of measuring transition temperature of plastics", but as in the examples shown later, when it is in a liquid state at room temperature (23 to 25°C), it can also be visually confirmed that the glass transition temperature is room temperature or less.

Component (C) may be of any type, as long as its Mw satisfies the above range, and may be a natural or synthetic polymer compound. Examples of natural polymer compounds include regenerated cellulose polymer compounds such as cellophane and triacetyl cellulose. Examples of synthetic polymer compounds include addition polymerization polymer compounds such as polyolefin resins, vinyl chloride resins, vinyl acetate resins, (meth)acrylic resins, epoxy resins, and polyurethane resins; polycondensation polymer compounds such as amide resins, polycarbonate resins, polyester resins, alkyd resins, and polyimide resins; and addition condensation polymer compounds such as phenol resins, urea resins, and melamine resins. Among these, synthetic polymer compounds are preferred as component (C), and addition polymerization polymer compounds are more preferred, with polyolefin resins and (meth)acrylic resins being even more preferred. In particular, (meth)acrylic resins are most preferred because there are many options for the constituent monomers, making it easy to control the chemical structure and easy to control the SP value within the above range. The organic polymer compounds listed above may be used alone or in combination of two or more.

In component (C), the (meth)acrylic resin is an organic polymer compound obtained by polymerizing a (meth)acrylic monomer having a radically polymerizable double bond. The (meth)acrylic resin preferably has a hydrocarbon group on the side chain, and the number of carbon atoms in this hydrocarbon group is usually 1 to 24, but is preferably 2 or more, more preferably 4 or more, and is preferably 22 or less, more preferably 18 or less, even more preferably 12 or less, and particularly preferably 8 or less. Within the above range, the longer the carbon number of the alkyl group on the side chain of component (C), the more likely it is to segregate on the coating surface when cured, and the more likely the anti-blocking properties are to be improved, and the shorter the chain, the more likely the surface hardness is to be improved. The hydrocarbon group on the side chain of the (meth)acrylic resin may be a straight-chain hydrocarbon group, a chain-chain hydrocarbon group, or a cyclic hydrocarbon group, but a chain-chain hydrocarbon group is preferable, and a straight-chain hydrocarbon group is particularly preferable. In the present invention, a hydrocarbon group in a side chain of a (meth)acrylic resin means one that is bonded to a carbon atom in the main chain via at least an atom other than carbon.

The radical polymerizable monomer used as a raw material for the (meth)acrylic resin is not particularly limited, but from the viewpoint of antiblocking properties, it is preferable to use a compound represented by the following formula (1). That is, it is preferable that the (meth)acrylic resin contains a structural unit derived from the compound represented by the following formula (1). By using the compound represented by formula (1), it is possible to easily obtain a (meth)acrylic resin having a hydrocarbon group in the side chain, and it is also preferable because the polymerization of the (meth)acrylic resin is easy.
CH ₂ =C(R ¹ )-C(O)-X-R ² (1)
(R ¹ is a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R ² is an alkyl group having 1 to 24 carbon atoms which may have a hydroxyl group as a substituent, and X is -O- or -NH-.
)

In the above formula (1), R ¹ is more preferably a hydrogen atom or a methyl group. R ² is more preferably a hydrocarbon group having 2 or more carbon atoms, more preferably a hydrocarbon group having 4 or more carbon atoms, more preferably a hydrocarbon group having 22 or less carbon atoms, more preferably a hydrocarbon group having 18 or less carbon atoms, particularly preferably a hydrocarbon group having 12 or less carbon atoms, and most preferably a hydrocarbon group having 8 or less carbon atoms. The longer the carbon number of the hydrocarbon group of R ² is within the above range, the more likely it is to segregate on the coating surface, and the more antiblocking properties tend to be improved, and the shorter the chain, the more likely it is to improve surface hardness. The hydrocarbon group of R ² may be a linear hydrocarbon group, a chain hydrocarbon group, or a cyclic hydrocarbon group, but a chain hydrocarbon group is preferable, and a linear hydrocarbon group is particularly preferable. In addition, when R ² in formula (1) has a hydroxyl group, this hydroxyl group can impart hydrophilicity to component (C), so that the solubility parameter (SP) of component (C) can also be controlled. Furthermore, in formula (1), X is preferably --O--.

A plurality of types of the compound represented by the above formula (1) may be contained during the production of the organic polymer compound of component (C). In other words, a plurality of types of monomers having different structures corresponding to R ¹ , R ² and X may be used to produce the organic polymer compound of component (C).

Examples of compounds represented by formula (1) include (meth)acrylate monomers in which X in formula (1) is -O-, such as alkyl (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, decyl (meth)acrylate, lauryl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, and behenyl (meth)acrylate; hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and glycerin (meth)acrylate, isobornyl (meth)acrylate, cyclohexyl (meth)acrylate, and benzyl (meth)acrylate. Examples of compounds represented by formula (1) include (meth)acrylamide monomers in which X in formula (1) is -NH-, such as alkyl (meth)acrylamides such as ethyl (meth)acrylamide, n-butyl (meth)acrylamide, i-butyl (meth)acrylamide, and t-butyl (meth)acrylamide; and N-hydroxyalkyl (meth)acrylamides such as N-hydroxyethyl (meth)acrylamide, N-hydroxypropyl (meth)acrylamide, and N,N-dihydroxyethyl (meth)acrylamide.

The organic polymer compound of component (C) may be copolymerized with a radical polymerizable monomer other than the compound represented by formula (1). Examples of such monomers include methoxy (poly) ethylene glycol (meth) acrylate, methoxy (poly) propylene glycol (meth) acrylate, methoxy (poly) ethylene glycol (poly) propylene glycol (meth) acrylate, methoxy tetramethylene glycol (meth) acrylate, octoxy (poly) ethylene glycol (meth) acrylate, octoxy (poly) propylene glycol (meth) acrylate, octoxy (poly) ethylene glycol (poly) propylene glycol (meth) acrylate, octoxy tetramethylene glycol (meth) acrylate, lauroxy (poly) ethylene glycol Glycol (meth)acrylic monomers having an alkyl group at the end, such as glycol (meth)acrylate and stearoxy (poly)ethylene glycol (meth)acrylate; (meth)acrylic monomers having a carboxyl group, such as (meth)acrylic acid; (poly)alkylene glycol (meth)acrylates, such as (poly)ethylene glycol (meth)acrylate, (poly)propylene glycol (meth)acrylate, (poly)ethylene glycol/(poly)propylene glycol (meth)acrylate, and tetramethylene glycol (meth)acrylate; and monomers having a phosphate ester group in the molecule, such as 2-(meth)acryloyloxyethyl phosphate. (meth)acrylic monomers having an epoxy group, such as glycidyl (meth)acrylate and methyl glycidyl (meth)acrylate; (meth)acrylic monomers having an oxolane group, such as tetrahydrofurfuryl (meth)acrylate and (meth)acryloyloxypropyl-1,3-dioxolane; (meth)acrylic monomers having an ethylene urea group, such as N-(2-(meth)acryloyloxyethyl)ethylene urea; (meth)acrylic monomers having a dicyclopentyl group, such as dicyclopentenyloxyethyl (meth)acrylate; tetramethylpiperidinyl (meth)acrylate, pentamethylpiperidinyl Examples of the monomers include (meth)acrylic monomers having an amino group such as ethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, (meth)acryloyloxyethyl trimethyl ammonium chloride, (meth)acryloyloxyethyl dimethyl benzyl ammonium chloride, (meth)acrylic monomers having an alkoxy group such as 3-methacryloxypropyl triethoxysilane, 3-acryloxypropyl trimethoxysilane, 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl methyl diethoxysilane, and styrene-based monomers such as styrene, p-chlorostyrene, and p-bromostyrene. In the organic polymer compound of component (C) used in the present invention, the above raw material monomers may be used alone or in combination of two or more.

Furthermore, the (meth)acrylic resin that can be used for component (C) may have an unsaturated double bond such as a (meth)acryloyl group. Examples of the method for introducing a (meth)acryloyl group into a (meth)acrylic resin include a method of reacting a compound having a (meth)acryloyl group and a carboxyl group with a (meth)acrylic resin having an epoxy group, a method of reacting a compound having a (meth)acryloyl group and an epoxy group with a (meth)acrylic resin having a carboxyl group, a method of reacting a compound having a (meth)acryloyl group and a carboxyl group with a (meth)acrylic resin having a hydroxyl group, a method of reacting a compound having a (meth)acryloyl group and a hydroxyl group with a (meth)acrylic resin having a carboxyl group, a method of reacting a compound having a (meth)acryloyl group and a hydroxyl group with a (meth)acrylic resin having an isocyanate group, and a method of reacting a compound having a (meth)acryloyl group and an isocyanate group with a (meth)acrylic resin having a hydroxyl group.

In the (meth)acrylic resin that can be used as component (C), the amount of (meth)acryloyl groups is preferably less than 2.0 mmol/g, more preferably 1.0 mmol/g or less, and even more preferably 0.5 mmol/g or less, from the viewpoint of antiblocking properties. On the other hand, there is no lower limit for the amount of (meth)acryloyl groups, and it is usually 0, i.e., there are no methacryloyl groups.

The reaction time for the radical polymerization reaction in producing the (meth)acrylic resin is usually 1 to 20 hours, and preferably 3 to 12 hours. The reaction temperature is usually 40 to 120°C, and preferably 50 to 100°C.

Examples of organic solvents that can be used in the radical polymerization reaction when producing the (meth)acrylic resin include ketone-based solvents such as acetone, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK); alcohol-based solvents such as ethanol, methanol, isopropyl alcohol (IPA), and isobutanol; ether-based solvents such as ethylene glycol dimethyl ether and propylene glycol monomethyl ether (PGM); ester-based 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. Note that such organic solvents may be left as they are after the synthesis of the (meth)acrylic resin and used as the organic solvent in the curable composition.

The radical polymerization initiator that can be used when producing the (meth)acrylic resin may be any known radical polymerization initiator, including, for example, 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 usually used in an amount of 0.01 to 5 parts by weight per 100 parts by weight of the total of the radical polymerizable monomers as raw materials.

The (meth)acrylic resin that can be used for component (C) can be produced by using the above-mentioned radical polymerizable monomers and a known radical polymerization reaction. The radical polymerization reaction can usually be carried out in an organic solvent in the presence of a radical polymerization initiator. In order to make the weight average molecular weight (Mw) of the (meth)acrylic resin fall within the above range, it is possible to control the polymerization conditions, such as the polymerization temperature, the amount of polymerization initiator, the amount of chain transfer agent, the solids concentration, and the method of adding the monomer.

When obtaining a (meth)acrylic resin, it is preferable to use a chain transfer agent because it is easy to control the weight average molecular weight (Mw). The amount of the chain transfer agent used is preferably 0.1 to 25 parts by weight, more preferably 0.5 to 20 parts by weight, and even more preferably 1.0 to 15 parts by weight, per 100 parts by weight of the total of the radical polymerizable monomers used as raw materials.

As the chain transfer agent that can be used when obtaining the (meth)acrylic resin, known ones can be used. For example, 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, methyl-3-mercaptopropionate, 2,2-(ethylenedioxy)diethanethiol, ethanethiol, 4-methylbenzenethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl thioglycolate, octyl 2-mercaptopropionate, octyl 3-mercaptopropionate, 2-ethylhexyl mercaptopropionate, butyl-3-mercaptopropionate, methyl-3-mercaptopropionate, 2,2-(ethylenedioxy)diethanethiol, ethanethiol, 4-methylbenzenethiol, octadecanethiol, cyclohexyl mercaptan, thiophenol, octyl 2-mercaptopropionate, octyl 3-mercaptopropionate, 2-ethylhexyl mercaptopropionate, butyl-3-mercaptopropionate, methyl-3-mercaptopropionate, 2,2-(ethylenedioxy)diethanethiol, ethanethiol, 4-methylbenzenethiol, octadecanethiol, cyclohexyl mercaptan ... Examples of thiol-based compounds include 2-mercaptoethyl mercaptan, 1,8-dimercapto-3,6-dioxaoctane, decane trithiol, dodecyl mercaptan, diphenyl sulfoxide, dibenzyl sulfide, 2,3-dimethylmercapto-1-propanol, mercaptoethanol, thiosalicylic acid, thioglycerol, thioglycolic acid, 3-mercaptopropionic acid, thiomalic acid, mercaptoacetic acid, mercaptosuccinic acid, 2-mercaptoethanesulfonic acid, 3-mercaptopropyltrimethoxysilane, and 3-mercaptopropylmethyldimethoxysilane.

The (meth)acrylic resin that can be used as component (C) can be produced by the method described above, but commercially available products can also be used as they are. Examples of commercially available products include "Polyflow No. 75", "Polyflow No. 77", "Polyflow No. 90", "Polyflow No. 50EHF", "Polyflow No. 85HF", "Polyflow No. 95", "Polyflow No. 99C", "Polyflow No. 7", "Polyflow No. 54N", "Polyflow KL-800" (all manufactured by Kyoeisha Chemical Co., Ltd.), "LF1984", "LF1983", "LHP90", "LHP95", "UVX -271", "UVX-272", "UVX-190", "UVX-36", "UVX-35", "UVX-3750", "UVX-189" (all manufactured by Kusumoto Chemicals), "BYK-350", "BYK-352", "BYK-354", "BYK-356", "BYK-361N", "BYK-381", "BYK-392", "BYK-394", "BYK-3441", "BYK-3440" (all manufactured by BYK), etc.

The content of component (C) in the curable composition of the present invention is 0.01 parts by weight or more, preferably 0.1 parts by weight or more, relative to 100 parts by weight of component (A), from the viewpoint of improving antiblocking properties, while it is 20 parts by weight or less, preferably 10 parts by weight or less, more preferably 5 parts by weight or less, from the viewpoint of suppressing a decrease in surface hardness.

[Organic solvent]
The curable composition of the present invention preferably contains an organic solvent. When the curable composition of the present invention contains an organic solvent, the solid content concentration is preferably 5 to 95% by weight. A solid content concentration of 5% by weight or more is preferable from the viewpoint of transparency, which makes the dispersibility of the component (B) good, and is also preferable for preventing an unintended curing reaction (gelation, etc.) of the curable composition. A solid content concentration of 95% by weight or less is also preferable from the viewpoint of coatability and storage stability. From these viewpoints, the solid content concentration is more preferably 10% by weight or more, even more preferably 15% by weight or more, more preferably 90% by weight or less, even more preferably 85% by weight or less, and particularly preferably 80% by weight or less. In the present invention, the "solid content" means a component excluding the solvent, and includes not only solid components but also semi-solid and viscous liquid components.

The organic solvent is not particularly limited, and can be appropriately selected in consideration of the types of components (A), (B), and (C), the type of substrate used when forming the hard coat layer, the method of application to the substrate, and the like. Specific examples of organic solvents include saturated hydrocarbon solvents such as n-hexane, n-heptane, n-octane, n-decane, n-dodecane, 2,3-dimethylhexane, 2-methylheptane, 2-methylhexane, 3-methylhexane, and cyclohexane; aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone (MEK), acetone, methyl isobutyl ketone (MIBK), and cyclohexanone; diethyl ether, isopropyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ... Examples of such solvents include ether-based solvents such as ethylene glycol diethyl ether, propylene glycol monomethyl ether, anisole, and phenetole; ester-based solvents such as ethyl acetate, butyl acetate, isopropyl acetate, ethylene glycol diacetate, and propylene glycol monomethyl ether acetate; amide-based solvents such as dimethylformamide, diethylformamide, and N-methylpyrrolidone; cellosolve-based solvents such as methyl cellosolve, ethyl cellosolve, and butyl cellosolve; alcohol-based solvents such as methanol, ethanol, propanol, isopropanol, and butanol; and halogen-based solvents such as dichloromethane and chloroform.

These organic solvents may be used alone or in combination of two or more. Among these, it is preferable to use at least one selected from saturated hydrocarbon solvents, ester solvents, ether solvents, alcohol solvents, and ketone solvents.

[Polymerization initiator]
The curable composition of the present invention preferably contains a polymerization initiator in order to improve the curability. The polymerization initiator is preferably a photopolymerization initiator, and examples thereof include 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide. These polymerization initiators may be used alone or in combination of two or more.

From the viewpoint of enhancing the curability, the content of the polymerization initiator is preferably 0.01 parts by weight or more, more preferably 0.05 parts by weight or more, and even more preferably 0.1 parts by weight or more, per 100 parts by weight of component (A). From the viewpoint of the stability of the curable composition, the content of the polymerization initiator is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, even more preferably 5 parts by weight or less, and particularly preferably 3 parts by weight or less, per 100 parts by weight of component (A).

[Other ingredients]
The curable composition of the present invention may contain other components other than the component (A), the component (B), the component (C), the organic solvent, and the polymerization initiator, as long as the effect of the present invention is not impaired. Examples of other components include ultraviolet absorbers, hindered amine light stabilizers, fillers (excluding those corresponding to the component (B)), silane coupling agents (excluding those corresponding to the component (B)), reactive diluents (excluding those corresponding to the component (A)), antistatic agents, organic pigments, slip agents, dispersants, thixotropic agents (thickeners), defoamers, antioxidants, thermoplastic resins (excluding those corresponding to the component (C)), and the like.

[Method of producing curable composition]
The method for producing the curable composition of the present invention is not particularly limited, and the composition can be obtained, for example, by mixing components (A), (B), and (C) and, if necessary, an organic solvent, a polymerization initiator, other components, etc. When mixing the components, it is preferable to mix them uniformly using a disperser, a stirrer, etc.

[Cured product, laminate and hard-coated film]
A cured product (sometimes referred to as "cured product of the present invention") can be obtained by curing the curable composition of the present invention by irradiating it with active energy rays or the like. A laminate can also be obtained by applying the curable composition onto a substrate and irradiating it with active energy rays to form a hard coat layer. In particular, a hard coat film can be obtained by applying the curable composition onto a substrate or the like and curing it into a film. In the present invention, the term "application" is used as a concept that includes what is generally called "coating". In the present invention, the term "hard coat" refers to a product obtained by applying and curing a curable composition.

Examples of substrates used in the laminate include organic materials such as plastic substrates; inorganic materials such as metal substrates and glass substrates. Examples of plastic substrates include various synthetic resins, such as acrylonitrile-butadiene-styrene copolymer (ABS) resin, polycarbonate (PC) resin, polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin, polymethyl methacrylate (PMMA) resin, polystyrene (PS) resin, polyimide (PI) resin, polyolefin (PO) resin, etc. Examples of metal substrates include, but are not limited to, hot-rolled and cold-rolled steel sheets, hot-dip galvanized steel sheets, electrogalvanized steel sheets, tinplate, tin-free steel, and other various plated or alloy-plated steel sheets, stainless steel sheets, aluminum sheets, and other metal sheets. Furthermore, these may be subjected to various surface treatments such as phosphate treatment, chromate treatment, organic phosphate treatment, organic chromate treatment, and heavy metal replacement treatment such as nickel. As the glass substrate, in addition to ordinary glass, glass that has been subjected to various chemical treatments (for example, Corning Gorilla Glass (registered trademark) and Asahi Glass Dragontrail (registered trademark), etc.) and multi-component glass may be used. The curable composition of the present invention is suitable for plastic substrates and glass substrates, and is particularly suitable for plastic substrates, and among plastic substrates, is particularly suitable for polycarbonate resin, polyethylene terephthalate resin, and polymethyl methacrylate resin. The substrates listed above may be used alone or in combination of two or more.

Methods for applying (coating) the curable composition of the present invention onto a substrate include, for example, reverse coating, gravure coating, rod coating, bar coating, Mayer bar coating, die coating, spray coating, etc. In addition, the form of the cured product is not particularly limited, but in the case of a cured product obtained by curing by irradiating a substrate with active energy rays, it can usually be obtained in the form of a cured coating (cured film) on at least a portion of one side of the substrate.

The humidity when applying (coating) the curable composition onto a substrate is not particularly limited, and is usually 1 to 100%, and preferably 5 to 95%. In addition, when obtaining a cured product, it is preferable to dry the composition before irradiating it with active energy rays, and the drying temperature at this time is usually 40 to 160°C, and preferably 45 to 150°C.

Activin energy rays that can be used to cure the curable composition include ultraviolet rays, electron beams, X-rays, infrared rays, and visible light. Of these activation energy rays, ultraviolet rays and electron beams are preferred from the viewpoints of curability and prevention of resin deterioration.

When the curable composition is cured by ultraviolet irradiation, various ultraviolet irradiation devices can be used, and as the light source, a xenon lamp, a high-pressure mercury lamp, a metal halide lamp, an LED-UV lamp, etc. can be used. The ultraviolet irradiation amount is usually 10 to 10,000 mJ/ ^cm2 , and from the viewpoints of the curability of the curable composition and the flexibility of the cured product (cured film), it is preferably 30 to 5,000 mJ/ ^cm2 , and more preferably 50 to 3,000 mJ/ ^cm2 . The ultraviolet illuminance is usually 50 to 1,000 mW/ ^cm2 , and preferably 70 to 800 mW/ ^cm2 .

When the curable composition is cured by electron beam irradiation, various electron beam irradiation devices can be used. The dose (Mrad) of the electron beam is usually 0.5 to 20 Mrad, and is preferably 1 to 15 Mrad from the viewpoints of the curability of the curable composition, the flexibility of the cured product, and prevention of damage to the substrate.

The curable composition of the present invention has a high degree of freedom in coating conditions, and as shown in the examples below, various conditions such as humidity during coating, drying temperature, UV exposure amount, and UV illuminance can be selected from a wide range of conditions. Even if these conditions are changed, the cured product and laminate have the advantage of being easy to obtain good physical properties such as anti-blocking properties and transparency.

In another embodiment of the present invention, the laminate has a substrate layer and a hard coat layer, the hard coat layer contains the component (B), and has a haze value of less than 0.6% measured according to JIS K7136 (2000). The lower the haze value, the better the transparency, which is preferable. This laminate can be obtained by curing the curable composition of the present invention on a substrate. The substrates and curing conditions that can be used are as described above.

Furthermore, the hard coat film of the present invention contains the component (B) and the content thereof is 0.01 to 55% by weight based on the entire hard coat film. When the hard coat film contains the component (B) at the above lower limit or more, the antiblocking property is good, and when the content is below the above upper limit, the transparency is good. From these viewpoints, the content of the component (B) in the hard coat film is preferably 0.5% by weight or more, more preferably 1% by weight or more, even more preferably 2% by weight or more, and particularly preferably 3% by weight or more, while it is preferably 48% by weight or less, more preferably 41% by weight or less, even more preferably 34% by weight or less, particularly preferably 27% by weight or less, and most preferably 20% by weight or less. The content of the component (B) is based on the entire hard coat film. This hard coat film can be obtained by curing the curable composition of the present invention. The curing conditions are as described above.

The thickness of the hard coat film is preferably 0.5 μm or more, and more preferably 1 μm or more. On the other hand, the thickness of the hard coat film is preferably 100 μm or less, more preferably 75 μm or less, even more preferably 50 μm or less, particularly preferably 25 μm or less, and most preferably 15 μm or less.

[Application]
The curable composition of the present invention has excellent storage stability, a high degree of freedom in coating conditions, and the cured product and laminate obtained under various coating conditions have excellent antiblocking properties, transparency, recoatability, scratch resistance, curl resistance, etc. Therefore, it can be suitably used in any application where these properties are required, and is suitable as an optical adjustment film such as a retardation film and a brightness improvement film; a protective film used in a polarizing plate; an optical film such as an ITO film used in a touch panel and an electromagnetic wave prevention film. Furthermore, these optical films can be used in display devices (liquid crystal displays, light-emitting diode displays, electroluminescence displays, fluorescent displays, plasma display panels, etc.) installed in facilities such as bank ATMs, vending machines, personal digital assistants (PDAs), copiers, facsimiles, game machines, museums, and department stores, car navigation systems, multimedia stations (multifunctional terminals installed in convenience stores), mobile phones, monitor devices for railway vehicles, smartphones, tablets, etc.

The present invention will be described in more detail below based on examples, but the present invention is not limited to the following examples. Note that the various manufacturing conditions and evaluation result values in the following examples are meant as preferred upper or lower limit values in the embodiments of the present invention, and the preferred range may be a range defined by a combination of the above-mentioned upper or lower limit values and the values of the following examples or values of the examples.

[Evaluation method]
The curable compositions and cured films (hard coat films) produced in the following Examples and Comparative Examples were evaluated as follows.

<Anti-blocking property (AB property)>
Two hard coat films were prepared, and the surfaces on which the curable compositions produced in the hard coat film Examples were cured (the sides opposite the surface coated with the clear hard coat material) were overlapped in an atmosphere of 23°C and 60% relative humidity. After applying a load of about 1 kg with finger pressure, it was confirmed whether the cured film surfaces had easy slippage, and the anti-blocking property was evaluated according to the following criteria.
◎: Can be slid easily. ○: Can be slid without making noise. △: Can be slid but makes noise. ×: Cured film surfaces are in close contact with each other and cannot be slid against each other.

<Transparency>
The hard coat film was left for 12 hours in a thermostatic chamber at 23° C. and a relative humidity of 60%, and then the transparency was evaluated in terms of haze value (H%) according to JIS K7136 (2000), and the evaluation was performed according to the following criteria.
◯: The haze value of the cured film is less than 0.6% △: The haze value of the cured film is 0.6% or more and less than 1.0% ×: The haze value of the cured film is 1.0% or more

<Recoatability>
A line was drawn with an oil-based magic marker (Zebra's Maki Care Extra Fine (black) fine marker) on the surface of the hard coat film where the curable composition produced in each Example had been cured (the side opposite to the surface coated with the clear hard coat material), and 30 seconds after drawing the line, the line was evaluated as follows based on whether or not it repelled. From the viewpoint of recoatability, it is preferable that the line does not repel.
○: Not repelling lines ×: Repelling lines

<Scratch resistance>
Using #0000 steel wool, the surface of the hard coat film on which the curable composition produced in each Example had been cured (the side opposite to the surface coated with the clear hard coat material) was rubbed back and forth 10 times at ^a load of 176 g/cm2, and the degree of damage to the cured film caused by this was evaluated as follows. The fewer the scratches, the better.
○: 0 to 10 scratches △: 11 to 100 scratches ×: 101 or more scratches

<Storage stability>
The curable composition was allowed to stand at 50° C., the time until gelation was measured, and the composition was evaluated according to the following criteria.
◎: No gelation after 90 days ○: No gelation after 30 days, but gelation occurs within 90 days ×: Gelation occurs within 30 days

<Curl resistance>
A curable composition (coating liquid) was applied to a 100 μm thick PET film with four corners fixed to a glass plate using a bar coater so that the coating thickness after drying would be 3 to 5 μm, and the film was dried by heating at 80 ° C. for 1 minute, and cured by irradiating ultraviolet rays using an ultraviolet ray irradiation device manufactured by iGraphics Co. ^, Ltd. Model No.: UB0452-0752 [mercury lamp (with a main wavelength of 365 nm, emitting ultraviolet rays with wavelengths of 254 nm, 303 nm, and 313 nm)] so that the accumulated light amount was 500 mJ / cm 2. Thereafter, the film was cut to 10 cm x 10 cm. The curl value of the four corners was measured as the height from the desk immediately after cutting. The average value of the four measured points was taken as the curl value, and it was evaluated according to the following criteria.
○: Curl value is less than 11 mm △: Curl value is 11 mm or more and less than 25 mm ×: Curl value is 25 mm or more

<Refractive index>
The refractive index of the cured film on the substrate (PET) was measured using a digital Abbe refractometer DR-A1 manufactured by ATAGO.

[Raw materials]
The components (A) to (C) used as raw materials for the curable composition are as follows:

[Component (A)]
A-1: Kayarad DPHA manufactured by Nippon Kayaku Co., Ltd.
Mixture of dipentaerythritol tetraacrylate and dipentaerythritol hexaacrylate, weight average molecular weight (Mw): 700

A-2: Aronix M313 manufactured by Toagosei Co., Ltd.
A mixture of ethylene oxide isocyanurate (EO) modified diacrylate (molecular weight: 369) and ethylene oxide isocyanurate (EO) modified triacrylate (molecular weight: 423)

A-3: Viscoat #1000 manufactured by Osaka Organic Chemical Industry Co., Ltd.
Dendrimer acrylate (branched polyester polyol terminated acrylate),
Mw): 1,900
The method for measuring Mw of A-1 and A-3 is the same as that for component (C) described below.

[Component (B)]
The particles used as component (B) are as shown in the following Table 1. In Table 1, the "shape" and "dispersion state" were confirmed by a scanning electron microscope.

In Table 1, the particle size distribution values for b-2, b-3, and b-4 are smaller than the average primary particle diameter. The reason for this is presumably due to the difference in method, as the average primary particle diameter was confirmed using a scanning electron microscope, while the particle size distribution was measured optically using a laser diffraction particle size distribution meter. In particular, it is presumed that for b-2, an accurate value for the particle size distribution could not be measured due to the fact that the particles are somewhat long and chain-like, and thus aggregated. Also, it is presumed that this is due to the fact that b-3 and b-4 are in a dispersed state, rather than an aggregated state.

[Component (C)]
Commercially available products were used for C-1 to C-5, and those synthesized by the method described below were used for C-6 to C-11. The abbreviations used below are as follows.

MEK: methyl ethyl ketone DT: dodecanethiol EA: ethyl acrylate (a compound represented by the formula (1) in which R ¹ is a hydrogen atom and R ² is an ethyl group)
BMA: butyl methacrylate (a compound represented by the formula (1) in which R ¹ is a methyl group and R ² is a butyl group)
HEA: Hydroxyethyl acrylate (a compound represented by the formula (1) above, in which R ¹ is a hydrogen atom and R ² is a hydroxyethyl group)
BA: butyl acrylate (a compound represented by the formula (1) in which R ¹ is a hydrogen atom and R ² is a butyl group)
LMA: lauryl methacrylate (a compound represented by the formula (1) in which R ¹ is a methyl group and R ² is a dodecyl group)
HEMA: Hydroxyethyl methacrylate (a compound represented by the formula (1) in which R ¹ is a methyl group and R ² is a hydroxyethyl group)
EHA: 2-ethylhexyl acrylate (a compound represented by the formula (1) above, in which R ¹ is a hydrogen atom and R ² is a 2-ethylhexyl group)

C-1: Polyflow No. 36 manufactured by Kyoeisha Chemical Co., Ltd.
Acrylic polymer (liquid at room temperature), Mw: 10,000, SP value: 9.6

C-2: Polyflow No. 50EHF manufactured by Kyoeisha Chemical Co., Ltd.
Acrylic polymer (liquid at room temperature), Mw: 10,000, SP value: 9.7

C-3: Polyflow No. 75 manufactured by Kyoeisha Chemical Co., Ltd.
Acrylic polymer (liquid at room temperature), Mw: 2,400, SP value: 9.9

C-4: Polyflow No. 77 manufactured by Kyoeisha Chemical Co., Ltd.
Acrylic polymer (liquid at room temperature), Mw: 2,200, SP value: 10.3

C-5: Polyflow No. 90 manufactured by Kyoeisha Chemical Co., Ltd.
Acrylic polymer (liquid at room temperature), Mw: 12,000, SP value: 9.6

C-6:
A flask equipped with a thermometer, a stirrer, and a reflux condenser was charged with 250.33 g of MEK, 15.00 g of DT, 25.00 g of EA, 25.00 g of BMA, and 1.20 g of 2,2'-azobis(2,4-dimethylvaleronitrile), and a mixture of 25.00 g of EA, 25.00 g of BMA, and 10.40 g of MEK was added dropwise over 1.5 hours while reacting for 3 hours at 65°C. Thereafter, 0.60 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was further added and reacted for 3 hours, after which 10.80 g of MEK and 0.50 g of p-methoxyphenol were added and heated to 100°C to obtain a (meth)acrylic resin (liquid at room temperature).
Mw: 2,600, SP value: 10.2

C-7:
A flask equipped with a thermometer, a stirrer, and a reflux condenser was charged with 243.33 g of MEK, 15.00 g of DT, 9.00 g of HEA, 20.00 g of BA, 21.00 g of EHA, and 1.20 g of 2,2'-azobis(2,4-dimethylvaleronitrile), and a mixture of 9.00 g of HEA, 20.00 g of BA, 21.00 g of EHA, and 21.40 g of MEK was added dropwise over 1.5 hours, while reacting for 3 hours at 65°C. Thereafter, 0.60 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was further added and reacted for 3 hours, after which 8.97 g of MEK and 0.50 g of p-methoxyphenol were added and heated to 100°C to obtain an acrylic resin (liquid at room temperature).
Mw: 3,400, SP value: 10.8

C-8:
In a flask equipped with a thermometer, a stirrer, and a reflux condenser, 131.67 g of MEK, 5.00 g of DT, 20.00 g of EA, 20.00 g of BMA, 10.00 g of HEMA, and 1.20 g of 2,2'-azobis(2,4-dimethylvaleronitrile) were placed, and a mixture of 20.00 g of EA, 20.00 g of BMA, 10.00 g of HEMA, and 21.40 g of MEK was added dropwise over 1.5 hours, while reacting for 3 hours at 65°C. Thereafter, 0.60 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was further added and reacted for 3 hours, after which 8.90 g of MEK and 0.50 g of p-methoxyphenol were added and heated to 100°C, to obtain a (meth)acrylic resin (liquid at room temperature).
Mw: 6,100, SP value: 11.0

C-9:
Into a flask equipped with a thermometer, a stirrer, and a reflux condenser, 131.67 g of MEK, 5.00 g of DT, 20.00 g of EA, 20.00 g of BMA, 10.00 g of LMA, and 1.20 g of 2,2'-azobis(2,4-dimethylvaleronitrile) were placed, and a mixture of 20.00 g of EA, 20.00 g of BMA, 10.00 g of LMA, and 21.40 g of MEK was added dropwise over 1.5 hours, while reacting for 3 hours at 65°C. Thereafter, 0.60 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was further added and reacted for 3 hours, after which 8.90 g of MEK and 0.50 g of p-methoxyphenol were added and heated to 100°C, thereby obtaining a (meth)acrylic resin (liquid at room temperature).
Mw: 6,400, SP value: 10.2

C-10:
In a flask equipped with a thermometer, a stirrer, and a reflux condenser, 131.67 g of MEK, 9.00 g of HEA, 21.00 g of EHA, 20.00 g of BA, and 1.20 g of 2,2'-azobis(2,4-dimethylvaleronitrile) were placed, and a mixture of 9.00 g of HEA, 21.00 g of EHA, 20.00 g of BA, and 21.40 g of MEK was added dropwise over 1.5 hours while reacting for 3 hours at 65°C. Thereafter, 0.60 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was further added and reacted for 3 hours, after which 8.90 g of MEK and 0.50 g of p-methoxyphenol were added and heated to 100°C to obtain an acrylic resin (liquid at room temperature).
Mw: 21,600, SP value: 11.1

C-11:
A flask equipped with a thermometer, a stirrer and a reflux condenser was charged with 131.67 g of MEK, 25.00 g of BMA, 25.00 g of EA and 1.20 g of 2,2'-azobis(2,4-dimethylvaleronitrile), and a mixture of 25.00 g of BMA, 25.00 g of EA and 21.40 g of MEK was added dropwise over 1.5 hours while reacting for 3 hours at 65°C. Thereafter, 0.60 g of 2,2'-azobis(2,4-dimethylvaleronitrile) was further added and reacted for 3 hours, after which 8.90 g of MEK and 0.50 g of p-methoxyphenol were added and heated to 100°C to obtain a (meth)acrylic resin (liquid at room temperature).
Mw: 19,900, SP value: 10.4

(Method of measuring weight average molecular weight (Mw))
The measurement was carried out by GPC under the following conditions.
Equipment: Tosoh Corporation "HLC-8120GPC"
Column: "TSKgel Super H1000+H2000+H3000" manufactured by Tosoh Corporation
Detector: Differential refractive index detector (RI detector/built-in)
Solvent: Tetrahydrofuran Temperature: 40°C
Flow rate: 0.5mL/min Injection volume: 10μL
Concentration: 0.2% by weight
Calibration sample: Monodisperse polystyrene Calibration method: Polystyrene equivalent

[Polymerization initiator]
Irgacure 184: BASF Corporation, Irgacure (trademark) 184, 1-hydroxy-cyclohexyl-phenyl-ketone

Example 1-1
[Substrate with clear hard coat]
In a four-neck flask, 100 parts by weight of a mixture of dipentaerythritol tetraacrylate and dipentaerythritol hexaacrylate (Kayarad DPHA, manufactured by Nippon Kayaku Co., Ltd.) and 0.5 parts by weight of an acrylic polymer (Polyflow No. 75, manufactured by Kyoeisha Chemical Co., Ltd.) were mixed, and then 5 parts by weight of 1-hydroxy-cyclohexyl-phenyl-ketone (Irgacure (trademark) 184, manufactured by BASF) was added as a polymerization initiator, and further 105.5 parts by weight of methyl ethyl ketone was added to obtain a clear hard coat material. The above-mentioned clear hard coat material was applied to a 125 μm-thick transparent biaxially oriented polyethylene terephthalate (PET) film (Mitsubishi Plastics, Inc., Diafoil (trademark) O321E125) using a bar coater so that the coating thickness after drying would be 1 to 2 μm, and the film was dried by heating at 80° C. for 1 minute, and then cured by irradiating with ultraviolet light so that the accumulated light amount was 300 mJ/cm ^2. Note that the above-mentioned clear hard coat material was applied to compensate for haze caused by the unevenness of the substrate itself.

[Preparation of curable composition]
In a four-neck flask, component (A), component (B), and component (C) were mixed in the amounts shown in Table 2, and then the mixture was diluted with methyl ethyl ketone to a solid content of 50% by weight, thereby obtaining a curable composition.

[Coating process]
A curable composition was applied to the surface of the PET film opposite to the surface coated with the clear hard coat material using a bar coater so that the coating thickness after drying would be 1 to 2 μm (5 to 10 μm for the film used for refractive index evaluation), and the composition was dried by heating at 80° C. for 1 minute.

[Curing process]
The PET film on which the coating of the curable composition was formed was irradiated with ultraviolet light from a high-pressure mercury lamp with an output density of 120 W/cm at a position 15 cm below the light source using an EYE UV METER UVPF-A1, PD365 manufactured by EYE GRAPHICS, Inc., so that the cumulative light amount was 300 mJ/ ^cm2 (500 mJ/ ^cm2 for the film used to evaluate curl resistance) to obtain a cured film.

[evaluation]
The prepared curable compositions and the formed cured films (hard coat films) were evaluated for antiblocking property (AB property), transparency, refractive index, recoating property, scratch resistance, storage stability and curl resistance, and the results are shown in Table 2.

In Table 2, the parts by weight of each component indicate the amount excluding the solvent, and "-" for each ingredient indicates that the ingredient was not used, and "-" for "storage stability" and "curl resistance" indicates that the evaluation was not performed. These items in Table 2 have the same meaning in Tables 3 to 9.

<Examples 1-2 to 1-51, Comparative Examples 1-1 to 1-17>
Curable compositions were obtained in the same manner as in Example 1-1, except that the formulation of the curable composition was changed as shown in Tables 2 to 9. Each of the obtained curable compositions was subjected to the coating step and the curing step in the same manner as in Example 1-1 to obtain a cured film (hard coat film). The obtained curable compositions and hard coat films were used to evaluate antiblocking property (AB property), transparency, recoating property, and scratch resistance, and the results are shown in Tables 2 to 9. For Examples 1-2 to 1-4, storage stability and curl resistance were evaluated, and the results are shown in Table 2.

[Evaluation result (1)]
As shown in Table 2, all of Examples 1-1 to 1-8, which correspond to the curable composition of the present invention and further contain component (C), were good in antiblocking properties (AB properties), transparency, recoatability, and scratch resistance. In addition, Examples 1-1 to 1-3 used "A-2" corresponding to a polyfunctional (meth)acrylate having a nitrogen atom-containing heterocyclic structure and "A-3" corresponding to a polyfunctional (meth)acrylate having a dendrimer structure as component (A), and therefore had better curl resistance than Example 1-4, which did not use these. Example 1-9 corresponds to the curable composition of the present invention, and all of the AB properties, transparency, recoatability, and scratch resistance were good, but since particles with a relatively small d10 value were used as component (B), the AB properties were slightly inferior compared to Examples 1-1 to 1-8. Moreover, Example 1-10 corresponds to the curable composition of the present invention, and was good in all of the AB property, transparency, recoatability, and scratch resistance, but since component (C) was not used, the AB property was slightly inferior to Examples 1-1 to 1-8.

Examples 1-11 to 1-21 shown in Table 3 are examples in which the type of component (C) was changed from that of Example 1-2, but all of them had good AB properties, transparency, recoatability, and scratch resistance.
Examples 1-22 to 1-26 shown in Table 4 are examples in which the type of component (B) was changed from that of Example 1-4, but all of them had good AB properties, transparency, recoatability, and scratch resistance.
As shown in Tables 6 and 7, the type and amount of each of the components (A), (B) and (C) were changed, and all of them had good AB properties, transparency, Ricoh properties and scratch resistance. In particular, the refractive index can be easily controlled by changing the type and amount of the component (B) as shown in Table 7.

In Table 8, Comparative Example 1-1 is an example in which component (B) was not used compared to Example 1-4, but the antiblocking properties (AB properties) were poor. Comparative Example 1-2 is an example in which "B-5" corresponding to component (B) was used in a large amount, but the transparency was poor. Furthermore, Comparative Examples 1-3 to 1-7 are examples in which particles other than component (B) were used instead of component (B) used in the present invention compared to Example 1-4, but all of them had inferior AB properties to Example 1-4. Comparative Example 1-8 is an example in which particles with a large average primary particle size and d90 were used as particles other than component (B) instead of component (B) used in the present invention compared to Example 1-4, but the transparency was poor. Furthermore, Comparative Example 1-9 is an example in which particles with a larger d90 value than component (B) were used instead of component (B) used in the present invention compared to Example 1-4, but the transparency was poor.

On the other hand, in Table 8, comparing Example 1-10 with Comparative Examples 1-10 to 1-12, which do not use the component (B) used in the present invention and instead use "b-1," "b-3," and "b-5," which do not correspond to component (B), it can be seen that Example 1-10 has good AB properties. In other words, even if component (C) is not essential, by blending components (A) and (B) in predetermined amounts, the AB properties are improved and transparency, recoatability, and scratch resistance are also good.

Comparative examples 1-13 to 1-15 in Table 9 are examples in which, unlike Example 1-30, component (B) used in the present invention was not used, and instead "b-1", "b-4", and "b-5", which do not correspond to component (B), were used, respectively, but either the transparency or the AB properties were poor. In addition, comparative examples 1-16 and 1-17, which did not use component (B) used in the present invention, both had poor AB properties.

[Examples 2-1 to 2-28]
As shown in Tables 10 to 13, the curable compositions having the same formulation as those in Examples 1-1 to 1-3 and Example 1-27 were used, and the coating film thickness after drying was 1 to 2 μm using a bar coater on the opposite side of the clear hard-coat material-coated substrate described above, and then dried. Then, a cured film was obtained by irradiating ultraviolet rays. In the above operations, the humidity during coating, the drying temperature, the ultraviolet (UV) irradiation amount, and the ultraviolet (UV) illuminance were set as shown in Tables 10 to 13. The obtained cured films were evaluated for anti-blocking property (AB property) and transparency, and the results are shown in Tables 10 to 13.

[Evaluation result (2)]
Examples 2-1 to 2-7, 2-8 to 2-14, 2-15 to 2-21, and 2-22 to 2-28 are examples in which the coating conditions were changed to the same formulation as the curable compositions of Examples 1-1, 1-2, 1-3, and 1-27, respectively. As shown in Tables 10 to 13, it can be seen that the antiblocking properties and transparency were excellent under all coating conditions.

The curable composition of the present invention has excellent storage stability, a high degree of freedom in coating conditions, and the cured product and laminate obtained under various coating conditions have excellent antiblocking properties, transparency, recoatability, scratch resistance, curl resistance, etc. Therefore, it can be suitably used in any application where these properties are required, and is suitable as an optical adjustment film such as a retardation film and a brightness improvement film; a protective film used in a polarizing plate; an optical film such as an ITO film used in a touch panel and an electromagnetic wave prevention film. Furthermore, these optical films can be used in display devices (liquid crystal displays, light-emitting diode displays, electroluminescence displays, fluorescent displays, plasma display panels, etc.) installed in facilities such as bank ATMs, vending machines, personal digital assistants (PDAs), copiers, facsimiles, game machines, museums, and department stores, car navigation systems, multimedia stations (multifunctional terminals installed in convenience stores), mobile phones, monitor devices for railway vehicles, smartphones, tablets, etc.

Claims (10)

A curable composition comprising the following components (A), (B) and (C), and containing 0.01 to 110 parts by weight of component (B) per 100 parts by weight of component (A).
Component (A): A compound containing at least one polyfunctional (meth)acrylate selected from the group consisting of polyfunctional (meth)acrylates having a nitrogen atom-containing heterocyclic structure, polyfunctional (meth)acrylates having a dendrimer structure, and polyfunctional (meth)acrylates having a hyperbranched polymer structure. Component (B): Silica particles having an average primary particle size of 10 to 50 nm, and a d90 of 250 to 1,000 nm , a d10 of 20 to 150 nm, and a d50 of 30 to 500 nm, as measured by a laser diffraction particle size distribution meter, with the value of [average primary particle size]/[d90] being 0.02 to 0.20. Component (C): A (meth)acrylic resin having a weight average molecular weight (Mw) of 2,100 to 200,000 and a solubility parameter (SP value) of 9.3 to 12.6. The curable composition according to claim 1 , wherein the weight average molecular weight of component (A) is less than 2,100, and the content of component (C) is 0.01 to 20 parts by weight per 100 parts by weight of component (A). The curable composition according to claim 1 or 2 , wherein the total content of the polyfunctional (meth)acrylate is 1 to 65% by weight based on the total content of component (A). The curable composition according to any one of claims 1 to 3 , which contains an organic solvent and has a solid content concentration of 5 to 95% by weight. The curable composition according to claim 4 , wherein the organic solvent is at least one selected from the group consisting of saturated hydrocarbon solvents, ester solvents, ether solvents, alcohol solvents, and ketone solvents. The curable composition according to any one of claims 1 to 5 , further comprising a polymerization initiator in an amount of 0.01 to 20 parts by weight based on 100 parts by weight of the component (A). A cured product obtained by irradiating the curable composition according to any one of claims 1 to 6 with active energy rays. A laminate having a substrate and a hard coat layer, the hard coat layer being formed by applying the curable composition according to any one of claims 1 to 6 onto the substrate and irradiating the applied composition with active energy rays. The laminate of claim 8 , wherein the substrate is a plastic substrate. The laminate according to claim 9 , wherein the plastic substrate is at least one selected from the group consisting of a polycarbonate resin, a polyethylene terephthalate resin, and a polymethyl methacrylate resin.