Active energy ray-curable composition, cured product, and film

Abstract

An object of the present invention is to provide an active energy ray-curable composition capable of forming a cured coating film having excellent anti-glare properties and transparency, a cured product, and a film.SOLUTION: The present invention relates to an active energy ray-curable composition containing an epoxy (meth) acrylate (A), a polyfunctional (meth) acrylate (B), a bifunctional (meth) acrylate (C), organic fine particles (D), a quaternary ammonium salt monomer (E), and a mixed solvent (F), wherein the polyfunctional (meth) acrylate (B) excludes the epoxy (meth) acrylate (A) and the bifunctional (meth) acrylate (C). In addition, the bifunctional (meth) acrylate (C) is other than the epoxy (meth) acrylate (A)), the quaternary ammonium salt monomer (E) is at least one of a quaternary salt of dimethylaminopropylacrylamide-methyl chloride and a quaternized product of dimethylaminoethyl (meth) acrylate, and a ratio of the quaternary ammonium salt monomer (E) to 100 parts by mass of a total of the epoxy (meth) acrylate (A), the polyfunctional (meth) acrylate (B), and the bifunctional (meth) acrylate (C) is: 0.5 to 10 parts by mass, and a ratio of the proton solvent to the non-proton solvent in the mixed solvent (F) is 50 mass% to 85 mass% / 15 mass% to 50 mass%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an active energy ray-curable composition capable of forming a hard coat layer, a cured product thereof, and a film thereof. [Background technology]

[0002] Resin films are used in a variety of applications, such as scratch-prevention films for the surfaces of flat panel displays (FPDs) such as liquid crystal displays (LCDs), organic light-emitting diode (OLED) displays, and plasma displays (PDPs), decorative films (sheets) for the interior and exterior of automobiles, and low-reflection and heat-blocking films for windows. However, because the surface of a resin film is soft and has low scratch resistance, to compensate for this, it is common practice to coat the film surface with a hard coating agent made of an active energy ray-curable composition or the like and cure it to form a hard coating layer on the film surface.

[0003] In particular, in the field of optical components, typified by display applications, high gloss on the display surface can result in excessive light reflection on the product surface, causing defects. Therefore, it is necessary to place an anti-glare film or an anti-glare anti-reflection film having anti-glare functionality on the outermost surface of the display. For anti-glare films, a technique is known in which an active energy ray-curable composition containing particles with an average particle size of microns is used to form appropriate irregularities on the surface of the coating film obtained after curing, thereby diffusing light.

[0004] Known examples of such anti-glare films include those produced by hardening a coating liquid containing fine particles (surface-protruding particles) with a convex shape on the surface of a core particle, and a resin, etc. (Patent Document 1).

[0005] The surface-convex particles described in Patent Document 1 use inorganic fine particles for at least one of the core particles and the microparticles, which has been thought to pose problems with the affinity between the cured resin layer and the particle interface and with the transparency of the film. Therefore, an active energy ray-curable resin composition was developed that can impart excellent antiglare properties by using organic fine particles, and also has little deterioration in transparency and adhesion to the substrate (Patent Document 2).

[0006] However, the cured coating film obtained from the composition described in the examples of Patent Document 2 has a minimum haze value of 2.4%, but the transmission clarity is not disclosed. Furthermore, in order to achieve antiglare properties, it is necessary to add 8% by mass or more of water to the solvent, which poses a problem of coating film defects being easily caused by uneven drying during coating. Therefore, with conventional technology, it has been difficult to achieve both transparency and antiglare properties while suppressing coating film defects caused by uneven drying during coating. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-4163 [Patent Document 2] Japanese Patent Application Laid-Open No. 2005-272582 Summary of the Invention [Problem to be solved by the invention]

[0008] The problem to be solved by the present invention is to provide an active energy ray-curable composition, a cured product, and a film that are capable of forming a cured coating film that suppresses uneven drying during coating, has excellent antiglare properties and transparency, and is also excellent in abrasion resistance. [Means for solving the problem]

[0009] The present inventors conducted extensive research to solve the above-mentioned problems and found that antiglare properties are achieved by phase separation due to the difference in polarity between hydrophobic organic particles and hydrophilic epoxy (meth)acrylate. However, specific quaternary ammonium salt monomers are particularly hydrophilic and have the effect of promoting this phase separation. For this quaternary ammonium salt monomer to function effectively, it must be suspended in the coating composition, and the hydrophilic component, a protic solvent, must be at least 50% by mass. Specifically, they discovered that by using a specific quaternary ammonium salt monomer and further adjusting the ratio of protic solvent to aprotic solvent in the mixed solvent to a specific range, an active energy ray-curable composition capable of forming a cured coating film with excellent antiglare properties and transparency can be obtained, thereby completing the present invention.

[0010] The present invention relates to the following inventions. [1] An active energy ray-curable composition comprising an epoxy (meth)acrylate (A), a polyfunctional (meth)acrylate (B), a bifunctional (meth)acrylate (C), organic fine particles (D), a quaternary ammonium salt monomer (E), and a mixed solvent (F) (wherein the polyfunctional (meth)acrylate (B) excludes the epoxy (meth)acrylate (A) and the bifunctional (meth)acrylate (C), and the bifunctional (meth)acrylate (C) excludes the epoxy (meth)acrylate (A)), the quaternary ammonium salt monomer (E) is at least one of a quaternary salt of dimethylaminopropylacrylamide methyl chloride and a quaternary product of dimethylaminoethyl (meth)acrylate; the proportion of the quaternary ammonium salt monomer (E) is 0.5 to 10 parts by mass relative to 100 parts by mass in total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C), An active energy ray-curable composition in which the proportions of protonic solvent / aprotonic solvent in the mixed solvent (F) are 50% by mass to 85% by mass / 15% by mass to 50% by mass. [2] The active energy ray-curable composition according to [1], wherein the proportion of the epoxy (meth)acrylate (A) is 20 to 50 parts by mass, the proportion of the polyfunctional (meth)acrylate (B) is 30 to 70 parts by mass, and the proportion of the bifunctional (meth)acrylate (C) is 0.5 to 20 parts by mass, relative to 100 parts by mass in total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C). [3] The active energy ray-curable composition according to [1] or [2], which contains a photopolymerization initiator (G). [4] The active energy ray-curable composition according to any one of [1] to [3], wherein the epoxy (meth)acrylate (A) is a reaction product of polyglycidyl methacrylate and acrylic acid. [5] The active energy ray-curable composition according to any one of [1] to [4], wherein the bifunctional (meth)acrylate (C) is a compound having a nurate skeleton and a hydroxyl group in the molecule. [6] The active energy ray-curable composition according to any one of [1] to [5], wherein the organic fine particles (D) are an acrylic-styrene copolymer. [7] The active energy ray-curable composition according to any one of [1] to [6], wherein the refractive index (n) of the organic fine particles (D) is from 1.51 to 1.53. [8] The active energy ray-curable composition according to any one of [1] to [7], wherein the organic fine particles (D) have an average primary particle size of 0.5 to 3 μm. [9] The active energy ray-curable composition according to any one of [1] to [8], wherein the proportion of the organic fine particles (D) is 1 to 10 parts by mass per 100 parts by mass of the total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C).

[10] A cured product of the active energy ray-curable composition according to any one of [1] to [9].

[11] A film having a cured coating film of the active energy ray-curable composition according to any one of [1] to [9]. [Effects of the Invention]

[0011] The active energy ray-curable composition of the present invention can form a cured coating film that suppresses uneven drying during coating, has excellent antiglare properties and transparency, and is also excellent in abrasion resistance.

[0012] Therefore, a film having a hard coat layer formed from a cured coating film of the active energy ray-curable composition of the present invention can be suitably used as an optical film for flat panel displays (FPDs) such as liquid crystal displays (LCDs), organic light-emitting diode displays (OLEDs), and plasma displays (PDPs). DETAILED DESCRIPTION OF THE INVENTION

[0013] <Active energy ray-curable composition> The active energy ray-curable composition of the present invention (hereinafter sometimes simply referred to as "composition") contains, as essential components, an epoxy (meth)acrylate (A), a polyfunctional (meth)acrylate (B), a bifunctional (meth)acrylate (C), organic fine particles (D), a quaternary ammonium salt monomer (E), and a mixed solvent (F). However, the polyfunctional (meth)acrylate (B) excludes the epoxy (meth)acrylate (A) and the bifunctional (meth)acrylate (C). Furthermore, the bifunctional (meth)acrylate (C) excludes the epoxy (meth)acrylate (A). The quaternary ammonium salt monomer (E) is at least one of a quaternary salt of dimethylaminopropylacrylamide methyl chloride and a quaternary product of dimethylaminoethyl (meth)acrylate, the proportion of the quaternary ammonium salt monomer (E) is 0.5 to 10 parts by mass relative to 100 parts by mass of the total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C), and the proportions of the protonic solvent / aprotonic solvent in the mixed solvent (F) are 50% by mass to 85% by mass / 15% by mass to 50% by mass. In the present invention, "(meth)acrylate" refers to either or both of acrylate and methacrylate, "(meth)acryloyl" refers to either or both of acryloyl and methacryloyl, and "(meth)acrylic" refers to either or both of acrylic and methacrylic. Furthermore, all compounds having a polymerizable functional group in the composition, including the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C), may be collectively referred to as "radical polymerizable compounds."

[0014] [Epoxy (meth)acrylate (A)] The epoxy (meth)acrylate (A) may be, for example, an addition reaction product of an unsaturated monocarboxylic acid and an epoxy compound. The epoxy (meth)acrylate (A) may be used alone or in combination of two or more kinds.

[0015] Examples of the unsaturated monocarboxylic acid that can be used include (meth)acrylic acid, crotonic acid, and cinnamic acid. These compounds may be used alone or in combination of two or more. Among these, it is preferable to use (meth)acrylic acid from the viewpoint of scratch resistance.

[0016] Examples of the epoxy compound include epoxy compounds having a bisphenol A skeleton, such as bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, and brominated bisphenol A diglycidyl ether; epoxy compounds having a bisphenol F skeleton, such as bisphenol F diglycidyl ether; epoxy compounds having a hydrogenated phthalic acid skeleton; and compounds having an epoxy group and a (meth)acryloyl group, such as glycidyl (meth)acrylate, 4-hydroxybutyl acrylate glycidyl ether, and 3,4-epoxycyclohexylmethyl (meth)acrylate. These compounds may be used alone or in combination, or polymers thereof may be used. Among these, from the viewpoint of scratch resistance, it is preferable to use an epoxy group and a (meth)acrylic compound, and it is more preferable to use a polymer of glycidyl (meth)acrylate.

[0017] When the polymer of the epoxy compound is used as a raw material for the epoxy (meth)acrylate (A), a solvent may be used in combination to adjust the viscosity. Examples of the solvent that can be used include methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, and butyl acetate. These solvents may be used alone or in combination of two or more. When the solvent is used, the content is preferably in the range of 50 to 150 parts by mass per 100 parts by mass of the epoxy (meth)acrylate (A).

[0018] When a polymer of the epoxy compound is used as a raw material for the epoxy (meth)acrylate (A), the viscosity of the epoxy (meth)acrylate (A) containing a solvent is preferably in the range of 300 to 20,000 mPa·s, more preferably in the range of 700 to 6,000 mPa·s, in order to further improve the coating stability when forming a hard coat layer. The viscosity is a value measured using a B-type viscometer.

[0019] The content of the epoxy (meth)acrylate (A) is preferably 20 to 50% by mass, more preferably 23 to 45% by mass, and particularly preferably 25 to 40% by mass, based on 100% by mass of the total of the epoxy (meth)acrylate (A), polyfunctional (meth)acrylate (B), and bifunctional (meth)acrylate (C). Furthermore, the content of the epoxy (meth)acrylate (A) is preferably 18 to 45% by mass, more preferably 20 to 40% by mass, and particularly preferably 25 to 35% by mass, based on 100% by mass of the total of the radically polymerizable compounds. By setting the content within this range, particle aggregation of the organic fine particles (D) progresses efficiently during the coating and drying process, enabling a well-balanced improvement in both the suppression of drying unevenness and the antiglare properties of the cured coating film.

[0020] [Multifunctional (meth)acrylate (B)] The polyfunctional (meth)acrylate (B) is a compound having three or more (meth)acryloyl groups in the molecule, or a mixture containing a plurality of such compounds, which does not fall under the category of the epoxy (meth)acrylate (A) or the bifunctional (meth)acrylate (C). The polyfunctional (meth)acrylate (B) may be used alone or in combination of two or more.

[0021] Examples of the polyfunctional (meth)acrylate (B) that can be used include trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol hexa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, and tripentaerythritol octa(meth)acrylate.

[0022] Among these, in terms of obtaining even better scratch resistance, it is more preferable to use one or more compounds selected from the group consisting of tripentaerythritol octa(meth)acrylate, tripentaerythritol hepta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, dipentaerythritol penta(meth)acrylate, pentaerythritol tetra(meth)acrylate, and pentaerythritol tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate and pentaerythritol tri(meth)acrylate are more preferable.

[0023] The content of the polyfunctional (meth)acrylate (B) is preferably 30 to 70% by mass, more preferably 40 to 65% by mass, and particularly preferably 50 to 60% by mass, based on 100% by mass of the total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C). The content of the polyfunctional (meth)acrylate (B) is preferably 30 to 65% by mass, more preferably 35 to 60% by mass, and particularly preferably 40 to 55% by mass, based on 100% by mass of the total of the radically polymerizable compounds. By adjusting the content within this range, a good balance of transparency, antiglare properties, and scratch resistance of the cured coating film can be achieved.

[0024] [Bifunctional (meth)acrylate (C)] Examples of the bifunctional (meth)acrylate (C) include 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, Examples of the di(meth)acrylate include dihydric alcohol di(meth)acrylates such as pyrene glycol di(meth)acrylate and tripropylene glycol di(meth)acrylate; polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, di(meth)acrylate of tris(2-hydroxyethyl)isocyanurate; di(meth)acrylates of diols obtained by adding 4 moles or more of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol; and di(meth)acrylates of diols obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A.

[0025] As the bifunctional (meth)acrylate (C), it is preferable to use a compound having a nurate skeleton and a hydroxyl group in the molecule, rather than the above. Examples of such a compound having a nurate skeleton include tris(2-hydroxyethyl)isocyanurate di(meth)acrylate, bis(2-hydroxyethyl)isocyanurate di(meth)acrylate, and isocyanuric acid derivatives such as compounds in which the starting material for these compounds, hydroxyethyl (meth)acrylate, is replaced with ethylene oxide (EO), propylene oxide, or ε-caprolactone-modified hydroxyethyl (meth)acrylate. Among these, tris(2-hydroxyethyl)isocyanurate di(meth)acrylate is particularly preferred. Because tris(2-hydroxyethyl)isocyanurate di(meth)acrylate has a polar structure consisting of a hydroxyl group and a nurate skeleton, it can promote aggregation of the hydrophobic organic fine particles (D) and further improve antiglare properties.

[0026] The content of the bifunctional (meth)acrylate (C) is preferably in the range of 0.5 to 20% by mass, more preferably 2.0 to 15% by mass, and particularly preferably 3.0 to 12% by mass, based on 100% by mass of the total of the epoxy (meth)acrylate (A), polyfunctional (meth)acrylate (B), and bifunctional (meth)acrylate (C). Furthermore, the content of the bifunctional (meth)acrylate (C) is preferably in the range of 0.3 to 15% by mass, more preferably 0.5 to 12% by mass, and particularly preferably 2.0 to 10% by mass, based on 100% by mass of the total of the radically polymerizable compounds. By adjusting the content within these ranges, both the transparency and antiglare properties of the cured coating film can be improved in a balanced manner.

[0027] [Organic fine particles (D)] The organic fine particles (D) used in the present invention are used to create irregularities on the surface of the cured coating film to impart antiglare properties. They are not particularly limited, as long as they are insoluble in both the solvent and the radically polymerizable compound in the composition and are hydrophobic organic fine particles with a lower affinity for water than the epoxy (meth)acrylate (A), polyfunctional (meth)acrylate (B), and bifunctional (meth)acrylate (C). However, polymerized resin fine particle dispersions obtained by polymerization in water in the presence of surfactants such as dispersants, stabilizers, and emulsifiers, and polymerized resin fine particles with surfactants attached to the particle surface obtained by separating and drying this dispersion, are particularly preferred because they allow for uniform dispersion of polymerized resin fine particle aggregates. While surfactants are generally removed by washing, these polymerized resin fine particles have a lower affinity for water than radically polymerizable compounds because they cannot be completely removed by washing and remain on the particle surface.

[0028] Examples of the polymer resin microparticles that can be used include polyurethane-based microparticles, (meth)acrylic resin-based microparticles, styrene resin-based microparticles, benzoguanine resin-based microparticles, melamine resin-based microparticles, formaldehyde resin-based microparticles, and spherical microparticles made of crosslinked polymers such as acrylic-styrene copolymers. Of these, spherical microparticles made of acrylic-styrene copolymers and methyl methacrylate-styrene-ethylene glycol dimethacrylate copolymers are preferred because of their excellent solvent resistance and hardness.

[0029] In the present invention, the organic fine particles (D) aggregate into secondary particles to form an uneven surface. The average primary particle size is not particularly limited, as long as it is equal to or less than the thickness of the cured coating film. Taking into consideration thicker cured film thicknesses, the average particle size is 0.1 to 30 μm. For typical cured film thicknesses, such as 5 to 30 μm, the average particle size is preferably 0.5 to 3 μm. By setting the average primary particle size within this range, it is possible to form minute, finely-pitched unevenness, resulting in an active energy ray-curable composition capable of forming a cured coating film with excellent transparency and antiglare properties. Furthermore, the refractive index (n) of the organic fine particles (D) is preferably in the range of 1.51 to 1.53. This refractive index range reduces the difference in refractive index from the refractive index (n) of the cured coating film, which is in the range of 1.52 to 1.54, thereby significantly improving transparency. The organic fine particles (D) can be transparent, opaque, colored, etc., as required. Even when the thickness of the cured coating film is thinner than the average particle size of the organic fine particles (D), organic fine particles with a particle size smaller than the thickness of the cured coating film aggregate and appear on the coating film surface as secondary particles, thereby improving the effect of generating irregularities on the coating film surface and minimizing the loss of transparency.

[0030] The average primary particle size of the organic fine particles (D) is measured by a laser diffraction particle size distribution analyzer using a laser analysis scattering method. The refractive index (n) can be measured by any method, such as the minimum deviation angle method, the critical angle method (Abbe method or Pulfrich method), or the V-block method.

[0031] Organic fine particles (D) with a refractive index (n) in the range of 1.51 to 1.53 have a refractive index close to that of the cured coating film, making them transparent. However, due to the similar polarity difference between the organic particles and the cured coating film, it is generally difficult to cause the organic fine particles to aggregate in the coating film. The combination of a hydrophilic epoxy (meth)acrylate (A), a bifunctional (meth)acrylate (C), and a quaternary ammonium salt monomer (E) can efficiently aggregate the organic fine particles in the cured coating film.

[0032] The content of the organic fine particles (D) is preferably 1 to 10 parts by mass, more preferably 2 to 8 parts by mass, and particularly preferably 3 to 6 parts by mass, per 100 parts by mass of the total of the epoxy (meth)acrylate (A), polyfunctional (meth)acrylate (B), and bifunctional (meth)acrylate (C). The content of the organic fine particles (D) is preferably 1 to 10 parts by mass, more preferably 2 to 8 parts by mass, and particularly preferably 3 to 6 parts by mass, per 100 parts by mass of the total of the radically polymerizable compounds. By adjusting the content within these ranges, an appropriate uneven shape can be obtained, thereby obtaining an active energy ray-curable composition capable of forming a cured coating film with excellent transparency and antiglare properties.

[0033] [Quaternary ammonium salt monomer (E)] The quaternary ammonium salt monomer (E) is at least one of a quaternary salt of dimethylaminopropylacrylamide methyl chloride and a quaternary product of dimethylaminoethyl (meth)acrylate. Either one of the quaternary salt of dimethylaminopropylacrylamide methyl chloride and the quaternary product of dimethylaminoethyl (meth)acrylate may be used, or both. Antiglare properties are achieved by phase separation due to the difference in polarity between the hydrophobic organic fine particles (D) and the hydrophilic epoxy (meth)acrylate (A). The quaternary ammonium salt monomer (E) is particularly hydrophilic and has the effect of promoting the phase separation. Examples of the quaternary salt of dimethylaminopropylacrylamide methyl chloride include "DMAPAA-Q" manufactured by KJ Chemical Co., Ltd. Examples of the quaternary product of dimethylaminoethyl (meth)acrylate include "DQ-100" manufactured by Kyoeisha Co., Ltd.

[0034] The content of the quaternary ammonium salt monomer (E) is 0.5 to 10 parts by mass, preferably 1.5 to 9.5 parts by mass, per 100 parts by mass of the total of the epoxy (meth)acrylate (A), polyfunctional (meth)acrylate (B), and bifunctional (meth)acrylate (C). By setting the content within this range, an appropriate uneven shape is obtained, and an active energy ray-curable composition capable of forming a cured coating film with excellent antiglare properties is obtained.

[0035] [Mixed solvent (F)] The ratio of the mixed solvent (F) in the composition is protonic solvent / aprotonic solvent = 50% to 85% by mass / 15% to 50% by mass. This ratio is more preferably protonic solvent / aprotonic solvent = 55% to 80% by mass / 20% to 55% by mass. By increasing the ratio within this range, the proportion of the protonic solvent, which is a hydrophilic component in the solvent, can be made into a suspension state with good compatibility, making it easier to achieve the effect of phase separation due to the difference in polarity of the quaternary ammonium salt monomer (E).

[0036] Examples of the protonic solvent include alcohols such as methanol, ethanol, propanol, butanol, diacetone alcohol, isopropyl alcohol, diacetone alcohol, and dimethyl carbitol, as well as acetic acid, nitromethane, and formic acid. Examples of the aprotonic solvent include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl acetate, dimethyl carbonate, methyl ethyl ketone, methyl isobutyl ketone, acetone, acetylacetone, acetonitrile, propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether, tetrahydrofuran, N-methylpyrrolidone, dichloromethane, dimethyl sulfoxide, and toluene. Preferred protonic solvents are methanol, ethanol, propanol, and butanol, and preferred aprotonic solvents are propyl acetate, butyl acetate, methyl ethyl ketone, and methyl isobutyl ketone. These protonic and aprotonic solvents may be used alone or in combination. In addition to the organic solvents listed above, water having an ion exchange number may be added as a mixed solvent (F).

[0037] The content of the mixed solvent (F) is, for example, 30 to 80 mass %, and preferably 40 to 70 mass %, relative to 100 mass % of the composition.

[0038] [Photopolymerization initiator (G)] The composition preferably contains a photopolymerization initiator (G). Examples of the photopolymerization initiator (G) include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, oligo{2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone}, benzyl dimethyl ketal, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenyl ketone, Acetophenone compounds such as 2-methyl-2-morpholino(4-thiomethylphenyl)propan-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone; benzoin compounds such as benzoin, benzoin methyl ether, and benzoin isopropyl ether; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoindiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide; benzyl compounds such as benzyl (dibenzoyl), methylphenylglyoxyester, oxyphenylacetic acid 2-(2-hydroxyethoxy)ethyl ester, and oxyphenylacetic acid 2-(2-oxo-2-phenylacetoxyethoxy)ethyl ester; benzophenone, o-benzoylbenzoic acid methyl-4-phenylbenzophenone, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylated benzophenone, 3,3',4 Benzophenone compounds such as 4'-tetra(t-butylperoxycarbonyl)benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 2,4,6-trimethylbenzophenone, and 4-methylbenzophenone; thioxanthone compounds such as 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, and 2,4-dichlorothioxanthone; aminobenzophenone compounds such as Michler's ketone and 4,4'-diethylaminobenzophenone;Examples of photopolymerization initiators that can be used include 10-butyl-2-chloroacridone, 2-ethylanthraquinone, 9,10-phenanthrenequinone, camphorquinone, and 1-[4-(4-benzoylphenylsulfanyl)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propan-1-one. These photopolymerization initiators (G) may be used alone or in combination of two or more.

[0039] The content of the photopolymerization initiator (G) is preferably 0.5 to 10 parts by mass, more preferably 1 to 8 parts by mass, per 100 parts by mass of the total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C). The content of the photopolymerization initiator (G) is preferably 0.5 to 10 parts by mass, more preferably 1 to 8 parts by mass, per 100 parts by mass of the total of the radical polymerizable compounds.

[0040] [Other ingredients] In addition to the above, the active energy ray-curable composition of the present invention may contain, if necessary, a photosensitizer, a radical polymerizable compound such as a monofunctional (meth)acrylate compound that does not fall under the category of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), or the bifunctional (meth)acrylate (C), other additives, and the like.

[0041] The active energy ray-curable composition of the present invention can be appropriately mixed and applied to a substrate as a coating material, and then irradiated with active energy rays to form a cured coating film. The active energy rays include ionizing radiation such as ultraviolet rays, electron beams, α-rays, β-rays, and γ-rays. When irradiating ultraviolet rays as active energy rays to form a cured coating film, it is preferable to add the above-mentioned photopolymerization initiator to the composition to improve curability. Furthermore, if necessary, a photosensitizer can also be added to improve curability.

[0042] Examples of photosensitizers that can be used include tertiary amine compounds such as diethanolamine, N-methyldiethanolamine, and tributylamine; urea compounds such as o-tolylthiourea; and sulfur compounds such as sodium diethyldithiophosphate and s-benzylisothiuronium-p-toluenesulfonate.

[0043] When a photosensitizer is used, the amount used is preferably 0.05 to 20 parts by mass, and more preferably 0.5 to 10 parts by mass, when the total amount of the radical polymerizable compounds is 100 parts by mass.

[0044] Examples of the monofunctional (meth)acrylate compound include benzoyloxyethyl (meth)acrylate, benzyl (meth)acrylate, phenylethyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-phenyl-2-(4-acryloyloxyphenyl)propane; 2-phenyl-2-(4-(meth)acryloyloxyphenyl)propane; 2-phenyl-2-(4-(meth)acryloyloxyethoxyphenyl)propane; 2-phenyl-2-(4-(meth)acryloyloxypropoxyphenyl)propane; and chlorophenyl (meth)acrylates, bromophenyl (meth)acrylates, etc. Acrylate, chlorobenzyl (meth)acrylate, bromobenzyl (meth)acrylate, chlorophenylethyl (meth)acrylate, bromophenylethyl (meth)acrylate, chlorophenoxyethyl (meth)acrylate, bromophenoxyethyl (meth)acrylate, 2,4,6-trichlorophenyl (meth)acrylate, 2,4,6-tribromophenyl (meth)acrylate, 2,4,6-trichlorobenzyl (meth)acrylate, 2,4,6-tribromobenzyl (meth)acrylate, 2,4,6-trichlorophenoxyethyl (meth)acrylate, 2 Monofunctional (meth)acrylates having an aromatic ring, such as 4,6-tribromophenoxyethyl (meth)acrylate, o-phenylphenol (poly)ethoxy (meth)acrylate, and p-phenylphenol (poly)ethoxy (meth)acrylate; (meth)acrylates having an alicyclic alkyl group, such as cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, and glycidyl cyclocarbonate (meth)acrylate;(Meth)acrylates having an alkyl group having 1 to 22 carbon atoms, such as methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, octyl (meth)acrylate, dodecyl (meth)acrylate, and stearyl (meth)acrylate; styrene-based compounds such as styrene, α-methylstyrene, and chlorostyrene;

[0045] Examples of the other additives that can be used include polymerization inhibitors, surface conditioners, antistatic agents, antifoaming agents, viscosity modifiers, light stabilizers, weather stabilizers, heat stabilizers, ultraviolet absorbers, antioxidants, leveling agents, organic pigments, inorganic pigments, pigment dispersants, fine particles other than the organic fine particles (D), and inorganic fillers such as silicon oxide, aluminum oxide, titanium oxide, zirconia, and antimony pentoxide. These additives may be used alone or in combination of two or more.

[0046] As the fine particles, for example, inorganic fine particles such as spherical silica and amorphous silica can be used.

[0047] The particle size of the fine particles is preferably in the range of 0.5 to 5 μm, more preferably in the range of 0.8 to 3.5 μm, and even more preferably in the range of 1.0 to 2.5 μm, in order to obtain high cohesive force and even better antiglare properties. The particle size of the fine particles represents the particle size at which the cumulative amount accounts for 50% in the cumulative particle amount curve of the particle size distribution measurement results.

[0048] When the fine particles are used, the amount used is preferably in the range of 0.5 to 15% by mass, more preferably 1 to 7% by mass, in the active energy ray-curable composition, in order to obtain even better antiglare properties.

[0049] <Cured product> The cured product of the present invention is a cured product obtained by irradiating the composition with active energy rays and curing it, and may be in any shape such as a film or a three-dimensional object.

[0050] As described above, the active energy rays for curing the composition include ionizing radiation such as ultraviolet rays, electron beams, α-rays, β-rays, γ-rays, etc. When ultraviolet rays are used as the active energy rays, examples of devices for irradiating the ultraviolet rays include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, electrodeless lamps (fusion lamps), chemical lamps, black light lamps, mercury-xenon lamps, short arc lamps, helium-cadmium lasers, argon lasers, sunlight, and LED lamps.

[0051] <Film> The film of the present invention is obtained by coating at least one surface of a film substrate with the active energy ray-curable composition of the present invention, and then irradiating the coating with active energy rays to form a cured coating film.

[0052] The material of the film substrate used in the film of the present invention is preferably a resin with high transparency, for example, polyester resins such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyolefin resins such as polypropylene, polyethylene, and polymethylpentene-1; and cellulose resins such as cellulose acetate (diacetyl cellulose, triacetyl cellulose, and the like), cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate propionate butyrate, cellulose acetate phthalate, and cellulose nitrate. Examples of the resin include: fats; acrylic resins such as polymethyl methacrylate; vinyl chloride resins such as polyvinyl chloride and polyvinylidene chloride; polyvinyl alcohol; ethylene-vinyl acetate copolymers; polystyrene; polyamides; polycarbonates; polysulfones; polyethersulfones; polyetheretherketones; polyimide resins such as polyimides and polyetherimides; norbornene resins (e.g., "ZEONOR" manufactured by Nippon Zeon Co., Ltd.), modified norbornene resins (e.g., "ARTON" manufactured by JSR Corporation), and cyclic olefin copolymers (e.g., "APEL" manufactured by Mitsui Chemicals, Inc.). Furthermore, substrates made of two or more of these resins may be laminated together.

[0053] By using the active energy ray-curable composition of the present invention, a hard coat layer having excellent antiglare properties and transparency can be formed even when polymethyl methacrylate (hereinafter abbreviated as "PMMA") is used as the film substrate.

[0054] The film substrate may be in the form of a film or a sheet, and its thickness is, for example, in the range of 20 to 500 μm. When a film-shaped substrate film is used, its thickness is preferably in the range of 20 to 200 μm, more preferably in the range of 30 to 150 μm, and even more preferably in the range of 40 to 130 μm. By setting the thickness of the film substrate within this range, curling can be easily suppressed even when a hard coat layer made of a composition is provided on one side of the film.

[0055] Examples of methods for applying the composition to the film substrate include die coating, microgravure coating, gravure coating, roll coating, comma coating, air knife coating, kiss coating, spray coating, dip coating, spinner coating, brush coating, solid coating by silk screen, wire bar coating, and flow coating.

[0056] After the composition is applied to the substrate film, it is preferable to heat or dry it at room temperature to volatilize the solvent before irradiating it with active energy rays. Conditions for heat drying include, for example, a temperature of 50 to 100°C and a time of 0.5 to 10 minutes.

[0057] The thickness of the cured coating film formed on the film substrate from the composition is preferably 1 to 30 μm, more preferably 3 to 15 μm, and even more preferably 4 to 10 μm, since this ensures sufficient hardness of the cured coating film and can suppress curling of the film due to cure shrinkage of the coating film.

[0058] As described above, the active energy ray-curable composition of the present invention can form a hard coat layer that is excellent in coating stability, coating film appearance, antiglare properties, and transparency on various substrates including polymethyl methacrylate substrates.

[0059] Therefore, a film having a hard coat layer formed from a cured coating film of the active energy ray-curable composition of the present invention can be suitably used as an optical film for flat panel displays (FPDs) such as liquid crystal displays (LCDs), organic light-emitting diode displays (OLEDs), and plasma displays (PDPs). [Example]

[0060] The present invention will be explained in more detail below with reference to examples.

[0061] [Example 1] 55 parts by mass of a polyfunctional monomer [a mixture of pentaerythritol tetraacrylate and pentaerythritol triacrylate, "Aronix M305" manufactured by Toagosei Co., Ltd.], and epoxy acrylate (1) [a reaction product of polyglycidyl methacrylate and acrylic acid, solids content 50%, diluted with methyl isobutyl ketone, viscosity 1,000 mPa s, hereinafter abbreviated as "EA(1)"]. 70 parts by weight of EO-modified isocyanuric acid diacrylate urethane acrylate ("Aronix M215" manufactured by Toagosei Co., Ltd.), 10 parts by weight of dimethylaminopropyl acrylamide methyl chloride quaternary salt ("DMAPAA-Q" manufactured by KJ Chemical Co., Ltd.), 90 parts by weight of mixed alcohol ("Solmix A-7" ​​manufactured by Japan Alcohol Sales Co., Ltd.) (85% ethanol, 10% n-propanol, 5% methanol), 41 parts by weight of n-propyl acetate, and 5 parts by weight of photoinitiator (1-hydroxycyclohexyl phenyl ketone, "RUNTECURE 1104" manufactured by RUNTEC Chemical Co., Ltd.) were thoroughly mixed, and then 4.4 parts by weight of organic fine particles (crosslinked acrylic-styrene copolymer fine particles manufactured by Sekisui Plastics Co., Ltd., particle size 2.0 μm, refractive index 1.515) were added to prepare an active energy ray-curable composition with a nonvolatile content of 34.3% by weight. Thereafter, the following evaluation films were produced and evaluated.

[0062] [Examples 2 to 8 and Comparative Examples 1 to 12] The same procedure as in Example 1 was carried out except that the formulation was changed as shown in Table 1 below, and after preparing an active energy ray-curable composition, a film for evaluation was produced and evaluated.

[0063] [Preparation of evaluation samples] The active energy ray-curable composition was applied to a 60 μm-thick PMMA film using a bar coater to a film thickness of 5 μm, dried at 60°C for 1 minute, and then irradiated with a UV irradiation device (high-pressure mercury lamp, manufactured by Eye Graphics Co., Ltd.) in a nitrogen atmosphere at an irradiation dose of 75 mJ / m 2 The PMMA film having a cured coating was obtained as a sample for evaluation.

[0064] [Evaluation method for transparency and anti-glare properties] (1) Evaluation of haze and total light transmittance The haze and total light transmittance of the obtained evaluation sample were measured in accordance with JIS K7136:2000 using a haze meter ("NDH4000" manufactured by Nippon Denshoku Co., Ltd.) Transparency was evaluated based on the haze and total light transmittance. (2) Evaluation of transmission clarity The obtained evaluation sample was measured in accordance with JIS K7374:2007 using an image clarity measuring device ("ICM-IT" manufactured by Suga Test Instruments Co., Ltd.) at four optical comb widths of 0.125, 0.5, 1.0, and 2.0 mm. The total value of the four measured points was used for evaluation. The anti-glare property was evaluated by transmitted light clarity. Based on the above, films with a haze of 2-3%, a total light transmittance of 90% or more, and a transmission clarity of 360% or less were judged to have excellent transparency and anti-glare properties.On the other hand, films with a haze of 2-3%, a total light transmittance of 90% or more, and a transmission clarity of more than 360% were judged to have excellent transparency but poor anti-glare properties.

[0065] [Scratch resistance of evaluation film] The evaluation film obtained above was cut into a 30 cm × 2 cm rectangle and tested using a crockmeter-type friction tester (circular friction element 1.0 cm in diameter, steel wool #0000, load 200 g, 10 reciprocations). After the test, the surface of the cured coating film was visually observed and the scratch resistance was evaluated as follows: "○": Less than 10 scratches "X": 10 or more scratches, scratches on the entire test piece film.

[0066] [Uneven drying of evaluation film] The evaluation film obtained above was visually evaluated for uneven drying. "○": No uneven drying "×": Uneven drying

[0067] [Evaluation results] The evaluation results are shown in Tables 1 and 2.

[0068] [Table 1]

[0069] [Table 2]

[0070] The product names in the table are as follows: R-1104: 1-hydroxycyclohexyl phenyl ketone, trade name "RUNTECURE 1104" manufactured by RUNTEC Chemical Co., Ltd. EA(2): Epoxy acrylate(2) [reaction product of polyglycidyl methacrylate and acrylic acid, solids content 50%, diluted with butyl acetate, viscosity 5,000 mPa·s] M305 (PETA): Pentaerythritol tri- and tetraacrylate, trade name "Aronix M305" manufactured by Toagosei Co., Ltd. M215 (THEICDA): Isocyanuric acid EO-modified diacrylate, trade name "Aronix M215" manufactured by Toagosei Co., Ltd. Polymer resin particles: methyl methacrylate-styrene-ethylene glycol dimethacrylate copolymer (particle size 2.0 μm, refractive index 1.515) DMAPAA-Q: Dimethylaminopropylacrylamide methyl chloride quaternary salt, product name "DMAPAA-Q" manufactured by KJ Chemical Co. DQ-100: Dimethylaminoethyl methacrylate quaternary salt, product name "DQ-100" manufactured by Kyoeisha DMAA: Dimethylacrylamide, trade name "DMAA" manufactured by KJ Chemical Co. ACMO: Acryloylmorpholine, trade name "ACMO" manufactured by KJ Chemicals NIPAM: N-isopropylacrylamide, product name "NIPAM" manufactured by KJ Chemical Co. DEAA: Diethylacrylamide, trade name "DEAA" manufactured by KJ Chemical Co. DMAPAA: N-[3-(dimethylamino)propyl]acrylamide, trade name "DMAPAA" manufactured by KJ Chemical Co. 1SX-1055: Quaternary ammonium salt polymer, product name "Acrit 1SX-1055" manufactured by Taisei Fine Chemical Co., Ltd. (solid content 44%, diluted with propylene glycol monomethyl ether / methanol = 90 / 10) Solmix A-7: Trade name "Solmix A-7" ​​manufactured by Japan Alcohol Industry Co., Ltd. (a mixed alcohol solvent of 85% ethanol, 10% normal propanol, and 5% methanol)

[0071] From the evaluation results shown in Tables 1 and 2 above, it was found that the cured coating films of the active energy ray-curable compositions of the present invention in Examples 1 to 8 had low haze, high total light transmittance, excellent transparency, low transmission clarity, excellent anti-glare properties, and also excellent scratch resistance. On the other hand, Comparative Examples 1 and 2 shown in Table 1 did not contain the quaternary ammonium salt monomer (E) or the epoxy (meth)acrylate (A), and therefore had high transmission clarity but poor anti-glare properties. Comparative Example 3 shown in Table 2 contained a large amount of the quaternary ammonium salt monomer (E), at 15 parts by mass, and therefore had poor scratch resistance. Comparative Examples 4 to 9 shown in Table 2 did not contain the quaternary ammonium salt monomer (E) of the present invention, and therefore had high transmission clarity but poor anti-glare properties. Comparative Example 11 shown in Table 2 did not contain a proton solvent, and therefore had high transmission clarity but poor anti-glare properties. Comparative Example 12 shown in Table 2 contained a small amount of epoxy (meth)acrylate (A) and a large amount of polyfunctional (meth)acrylate (B), and had high transmitted light clarity but poor antiglare properties.

Claims

1. An active energy ray-curable composition comprising an epoxy (meth)acrylate (A), a polyfunctional (meth)acrylate (B), a bifunctional (meth)acrylate (C), organic fine particles (D), a quaternary ammonium salt monomer (E), and a mixed solvent (F) (wherein the polyfunctional (meth)acrylate (B) excludes the epoxy (meth)acrylate (A) and the bifunctional (meth)acrylate (C), and the bifunctional (meth)acrylate (C) excludes the epoxy (meth)acrylate (A)); the quaternary ammonium salt monomer (E) is at least one of a quaternary salt of dimethylaminopropylacrylamide methyl chloride and a quaternary product of dimethylaminoethyl (meth)acrylate; the proportion of the quaternary ammonium salt monomer (E) is 0.5 to 10 parts by mass relative to 100 parts by mass in total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C), The active energy ray-curable composition, wherein the ratio of the protonic solvent to the aprotonic solvent in the mixed solvent (F) is 50% by mass to 85% by mass / 15% by mass to 50% by mass.

2. relative to a total of 100 parts by mass of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C), 2. The active energy ray-curable composition according to claim 1, wherein a ratio of the epoxy (meth)acrylate (A) is 20 to 50 parts by mass, a ratio of the polyfunctional (meth)acrylate (B) is 30 to 70 parts by mass, and a ratio of the bifunctional (meth)acrylate (C) is 0.5 to 20 parts by mass.

3. The active energy ray-curable composition according to claim 1 or 2, further comprising a photopolymerization initiator (G).

4. 3. The active energy ray-curable composition according to claim 1, wherein the epoxy (meth)acrylate (A) is a reaction product of polyglycidyl methacrylate and acrylic acid.

5. 3. The active energy ray-curable composition according to claim 1, wherein the bifunctional (meth)acrylate (C) is a compound having a nurate skeleton and a hydroxyl group in the molecule.

6. 3. The active energy ray-curable composition according to claim 1, wherein the organic fine particles (D) are an acrylic-styrene copolymer.

7. 3. The active energy ray-curable composition according to claim 1, wherein the refractive index (n) of the organic fine particles (D) is 1.51 to 1.

53.

8. 3. The active energy ray-curable composition according to claim 1, wherein the organic fine particles (D) have an average primary particle size of 0.5 to 3 μm.

9. 3. The active energy ray-curable composition according to claim 1, wherein a ratio of the organic fine particles (D) is 1 to 10 parts by mass per 100 parts by mass of a total of the epoxy (meth)acrylate (A), the polyfunctional (meth)acrylate (B), and the bifunctional (meth)acrylate (C).

10. A cured product of the active energy ray-curable composition according to claim 1 or 2.

11. A film comprising a cured coating film of the active energy ray-curable composition according to claim 1 or 2.

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