CN117777774A - Active energy ray curable composition, cured product and film - Google Patents

Abstract

An object to be solved by the present invention is to provide an active energy ray curable composition, a cured product and a film capable of forming a cured coating film having excellent anti-glare properties and transparency. The present invention provides an active energy ray curable composition, a cured product using the same, and a film. The active energy ray curable composition contains organic fine particle dispersion (A) and epoxy (meth)acrylate (B). ), the organic fine particle dispersion (A) contains organic fine particles (a-1) and a dispersant (a-2), and the dispersant (a-2) is an alkanolamine compound.

Description

Active energy ray-curable composition, cured product and film

Technical Field

The present invention relates to an active energy ray-curable composition capable of forming a hard coating layer, a cured product and a film.

Background Art

Resin films can be used in various applications such as anti-scratch films on the surface of flat panel displays (FPD) such as liquid crystal displays (LCD), organic electroluminescence displays (OLED), plasma displays (plasma display panels (PDP)), decorative films (sheets) for interior and exterior decoration of automobiles, low-reflection films for windows, or heat-ray cut-off films. However, since the surface of the resin film is soft and has low scratch resistance, in order to compensate for the above disadvantages, the following operation is usually performed: a hard coating agent including an active energy ray-curable composition is applied to the film surface and hardened to provide a hard coating layer on the film surface.

In particular, in the field of optical parts represented by display applications, if the glossiness of the display surface is high, the light on the product surface will be reflected too much, which may cause problems. Therefore, it is required to arrange an anti-glare film or an anti-glare anti-reflection film with an anti-glare function on the outermost surface of the display. As an anti-glare film, the following technology is known: using an active energy ray-curable composition containing particles with an average particle size of micrometers, the surface of the coating obtained after curing is formed with appropriate concavities and convexities, thereby diffusing light.

As such an anti-glare film, there is known a film obtained by curing a coating liquid containing microparticles (surface convex particles) and a resin, wherein the microparticles (surface convex particles) are obtained by fixing tiny particles on the surface of core particles and the surface has a convex shape. (Patent Document 1)

The surface convex particles described in Patent Document 1 use inorganic microparticles in at least one of the core particles and the microparticles, so it is believed that there are problems in the affinity between the cured resin layer and the particle interface or the transparency of the film. Therefore, an active energy ray-curable resin composition that can provide excellent anti-glare properties and has little reduction in transparency or adhesion to the substrate by using organic microparticles has been developed. (Patent Document 2)

However, the minimum haze value of the cured coating obtained from the composition described in the examples of Patent Document 2 is 2.4%, and the transparent clarity is not disclosed. Therefore, there is a further problem in achieving both transparency and anti-glare properties.

[Prior art literature]

[Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2005-4163

[Patent Document 2] Japanese Patent Application Publication No. 2005-272582

Summary of the invention

[Problems to be solved by the invention]

The problem to be solved by the present invention is to provide an active energy ray-curable composition, a cured product, and a film capable of forming a cured coating film having excellent anti-glare properties and transparency.

[Technical means to solve the problem]

The present inventors have conducted intensive studies to solve the above problems and have found that an active energy ray-curable composition capable of forming a cured coating film having excellent antiglare properties and transparency can be obtained by blending a compound having a specific structure and organic fine particles, thereby completing the present invention.

That is, the present invention relates to the inventions described in the following [1] to [8].

The present invention includes the following contents.

[1] An active energy ray-curable composition comprising: an organic fine particle dispersion (A) and epoxy (meth)acrylate (B);

The organic fine particle dispersion (A) contains organic fine particles (a-1) and a dispersant (a-2).

The dispersant (a-2) is an alkanolamine compound.

[2] The active energy ray-curable composition according to [1], wherein the average primary particle diameter of the organic fine particles (a-1) is in the range of 0.5 μm to 3 μm.

[3] The active energy ray-curable composition according to [1] or [2], wherein the dispersant (a-2) has an amine value of 80 mgKOH/g or more.

[4] The active energy ray-curable composition according to any one of [1] to [3], wherein the epoxy (meth)acrylate (B) 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], further comprising a polyfunctional (meth)acrylate (C) different from the epoxy (meth)acrylate (B).

[6] The active energy ray-curable composition according to [5], wherein the polyfunctional (meth)acrylate (C) is a compound having a urate skeleton in the molecule.

[7] A cured product, which is a cured product of the active energy ray-curable composition according to any one of [1] to [6].

[8] A film comprising a cured coating film of the active energy ray-curable composition according to any one of [1] to [6].

[Effects of the Invention]

The active energy ray-curable composition of the present invention can form a cured coating film having excellent coating stability, coating film appearance, antiglare properties and transparency on various substrates including polymethyl methacrylate substrates.

Therefore, a film having a hard coat layer comprising a cured coating film of the active energy ray-curable composition of the present invention can be suitably used as an optical film used in flat panel displays (FPD) such as liquid crystal displays (LCDs), organic EL displays (OLEDs), and plasma displays (PDPs).

DETAILED DESCRIPTION

<Active energy ray-curable composition>

The active energy ray-curable composition of the present invention (hereinafter, sometimes simply referred to as “composition”) contains an organic fine particle dispersion (A) and epoxy (meth)acrylate (B) as essential components.

In the present invention, "(meth)acrylate" refers to one or both of acrylate and methacrylate, "(meth)acryloyl" refers to one or both of acryloyl and methacryloyl, and "(meth)acrylic" refers to one or both of acrylic and methacrylic. In addition, the organic fine particle dispersion (A) is sometimes referred to as the (A) component, and the same applies to other components.

＜＜Organic fine particle dispersion (A)＞＞

The organic fine particle dispersion (A) in the composition of the present invention contains at least organic fine particles (a-1) and a dispersant (a-2), and the dispersant (a-2) is an alkanolamine compound.

＜＜＜Organic fine particles (a-1)＞＞＞

The organic fine particles (a-1) used in the present invention are used to impart anti-glare properties to the surface of the cured coating film by making it uneven. They are not particularly limited as long as they are insoluble in any of the solvent and the radical polymerizable compound in the active energy ray-curable composition of the present invention and have a lower affinity for water than the radical polymerizable compound. However, in terms of having low affinity for both the radical polymerizable compound and water and uniformly dispersing the aggregates of the polymerized resin fine particles in the radical polymerizable compound, preferably, they are polymerized resin fine particles obtained by polymerizing in water in the presence of a surfactant such as a dispersant, a stabilizer, or an emulsifier, or polymerized resin fine particles having a surfactant attached to the particle surface obtained by separating and drying the dispersion. The polymerized resin fine particles obtained by these methods are generally washed away by the surfactant, but the surfactant cannot be completely washed away and remains on the particle surface, so the affinity for water is lower than that of the radical polymerizable compound.

As the organic microparticles (a-1), for example, spherical microparticles formed of cross-linked polymers such as polyurethane microparticles, (meth)acrylic resin microparticles, styrene resin microparticles, benzoguanine resin microparticles, melamine resin microparticles, and formaldehyde resin microparticles can be used. Among them, (meth)acrylic microparticles are preferred from the viewpoint of excellent solvent resistance and hardness.

In the present invention, since the organic fine particles (a-1) aggregate into secondary particles and form a concavoconvex surface, the average primary particle size thereof is not particularly limited as long as it is less than the film thickness of the cured coating film containing the composition of the present invention. In particular, when the cured film thickness is considered, it is 0.1 μm to 30 μm, but when the cured film thickness is assumed to be a normal cured film thickness, for example, a cured film thickness of about 5 μm to 30 μm, it is preferably 0.1 μm to 15 μm, more preferably 0.2 μm to 10 μm, and most preferably 0.5 μm to 3 μm. By setting the average primary particle size to these ranges, an active energy ray-curable composition capable of forming a cured coating film having excellent transparency and anti-glare properties can be obtained.

In addition, the organic microparticles (a-1) may be transparent microparticles, turbid microparticles, colored microparticles, etc. as needed. In addition, even when the film thickness of the hardened coating film containing the active energy ray-curable composition is thinner than the average particle size of the organic microparticles (a-1), the organic microparticles having a particle size smaller than the film thickness of the hardened coating film will aggregate to form secondary particles and appear on the surface of the coating film, thereby enhancing the effect of making the coating film surface uneven and reducing the reduction in transparency.

In the present invention, the average primary particle size of the organic fine particles (a-1) refers to an average primary particle size measured by a laser diffraction particle size distribution measuring apparatus using a laser analysis scattering method.

Therefore, the content of the organic fine particles (a-1) is preferably in the range of 0.5% to 20% by mass, more preferably in the range of 1% to 15% by mass, and particularly preferably in the range of 3% to 10% by mass in the solid content of the composition. By setting it in these ranges, an active energy ray-curable composition capable of forming a cured coating film having excellent transparency and anti-glare properties can be obtained.

In addition, the solid content of the composition refers to the total of all components in the composition except the solvent.

＜＜＜Dispersant (a-2)＞＞＞

The dispersant (a-2) is not particularly limited as long as it is an alkanolamine compound containing all of an alkyl group, a hydroxyl group, and an amino group in one molecule, and various known compounds can be used.

Examples of the dispersant (a-2) include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, methylethanolamine, methylisopropanolamine, methyldiethanolamine, methyldiisopropanolamine, diethanolisopropanolamine, diisopropanolethanolamine, tetrahydroxyethylethylenediamine, N,N-bis(2-hydroxyethyl)2-propanolamine, N,N-bis(2-hydroxypropyl)-N-(hydroxyethyl)amine, N,N-bis(2-hydroxyethyl)-N-(2-hydroxypropyl)amine, N,N,N',N'-tetrakis(2-hydroxypropyl)- Alkanolamines such as ethylenediamine and tri(2-hydroxybutyl)amine; alkanolamines having an amide bond which are reaction products of any alkanolamine and an unsaturated fatty acid; alkanolamines having a structure in which a part of an alkanolamine is bonded to a polymer, such as a polymer having a triisopropanolamine skeleton; alkanolamine salts such as (meth)acrylic acid, crotonic acid, phosphate ester, vinyl sulfonate, (meth)allyl sulfonate, 2-methylpropanesulfonic acid (meth)acrylamide, styrenesulfonic acid (for example, alkanolamine salts such as ethanolamine salts, diethanolamine salts, triethanolamine salts, dibutylaminoethanol salts, and triisopropanolamine salts), etc.

The amine value of the dispersant (a-2) is preferably 80 mgKOH/g or more and 200 mgKOH/g or less, more preferably 85 mgKOH/g or more and 180 mgKOH/g or less, and particularly preferably 90 mgKOH/g or more and 150 mgKOH/g or less. By setting the amine value in these ranges, an active energy ray-curable composition capable of forming a cured coating film having excellent transparency and anti-glare properties can be obtained.

The active energy ray-curable composition of the present invention can improve both anti-glare properties and transparency by adjusting the balance of the hydrophilicity of each component. More specifically, it is believed that phase separation is promoted between the hydrophobic organic microparticles (a-1) and the hydrophilic dispersant (a-2) which is an alkanolamine compound, and the organic microparticles (a-1) are easily aggregated into secondary particles, and the dispersant (a-2) is adsorbed on the surface of the secondary aggregates, thereby improving the transparency and anti-glare properties of the cured coating film.

＜＜Epoxy (meth)acrylate (B)＞＞

As epoxy (meth)acrylate (B), for example, an addition reaction product of an unsaturated monocarboxylic acid and an epoxy compound can be used.

As the unsaturated monocarboxylic acid, for example, (meth)acrylic acid, crotonic acid, cinnamic acid, etc. can be used. These compounds can be used alone or in combination of two or more. Among these, (meth)acrylic acid is preferably used in terms of scratch resistance.

As the epoxy compound, for example, epoxy compounds having a bisphenol A skeleton such as bisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, and brominated bisphenol A diglycidyl ether can be used; epoxy compounds having a bisphenol F skeleton such as bisphenol F diglycidyl ether; epoxy compounds having a hydrogenated phthalic acid skeleton; compounds having an epoxy group and a (meth)acryloyl group such as (meth) glycidyl acrylate, 4-hydroxybutyl acrylate glycidyl ether, and (meth) acrylate 3,4-epoxycyclohexylmethyl ester, etc. These compounds can be used alone, or two or more can be used in combination, and polymers of these can also be used. Among these, in terms of scratch resistance, it is preferred to use a compound having an epoxy group and a (meth)acryloyl group, and it is more preferred to use poly (meth) glycidyl acrylate as a polymer of (meth) glycidyl acrylate.

When the polymer of the epoxy compound is used as the raw material of the epoxy (meth) acrylate (B), a solvent may be used in combination in terms of adjusting the viscosity. As the solvent, for example, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, etc. may be used. These solvents may be used alone or in combination of two or more. The content of the solvent when used is preferably in the range of 50 to 150 parts by mass relative to 100 parts by mass of epoxy (meth) acrylate (B).

When the polymer of the epoxy compound is used as the raw material of the epoxy (meth) acrylate (B), the viscosity of the epoxy (meth) acrylate (B) including the solvent is preferably in the range of 100 mPa·s to 3,000 mPa·s, and more preferably in the range of 150 mPa·s to 2,000 mPa·s, in order to further improve the coating stability when forming the hard coating layer. In addition, the viscosity represents a value measured using a B-type viscometer.

The content of epoxy (meth)acrylate (B) is preferably in the range of 10% to 80% by mass, more preferably in the range of 15% to 50% by mass, and particularly preferably in the range of 20% to 40% by mass, relative to the total amount of the radical polymerizable compound in the active energy ray-curable composition. By setting it in the above range, both the transparency and the anti-glare property of the cured coating film can be improved in a well-balanced manner.

The active energy ray-curable composition of the present invention may contain a polyfunctional (meth)acrylate (C) other than the epoxy (meth)acrylate (B).

＜＜Multifunctional (meth)acrylate (C)＞＞

By containing the polyfunctional (meth)acrylate (C), the hardness of the cured product is improved.

As the multifunctional (meth)acrylate (C), trimethylolpropane tri(meth)acrylate, ethylene oxide-modified trimethylolpropane tri(meth)acrylate, propylene oxide-modified trimethylolpropane tri(meth)acrylate, di-trimethylolpropane tri(meth)acrylate, di-trimethylolpropane 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, tripentaerythritol octa(meth)acrylate, etc. can be used.

Moreover, as a polyfunctional (meth)acrylate (C), for example, a urethane (meth)acrylate can also be used. As an example of the urethane (meth)acrylate, the reaction product of a polyisocyanate and a (meth)acrylate having a hydroxyl group etc. are mentioned.

As the polyisocyanate, for example, aliphatic polyisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, and lysine triisocyanate; alicyclic polyisocyanates such as norbornane diisocyanate, isophorone diisocyanate, methylenebis(4-cyclohexyl isocyanate), 1,3-bis(isocyanatomethyl)cyclohexane, 2-methyl-1,3-diisocyanatocyclohexane, and 2-methyl-1,5-diisocyanatocyclohexane; aromatic polyisocyanates such as toluene diisocyanate, xylene diisocyanate, and diphenylmethane diisocyanate, etc. can be used. These polyisocyanates can be used alone or in combination of two or more.

The (meth)acrylate having a hydroxyl group is a compound having a hydroxyl group and a (meth)acryloyl group, and examples thereof include: trimethylolpropane di(meth)acrylate, ethylene oxide (EO)-modified trimethylolpropane (meth)acrylate, propylene oxide (PO)-modified trimethylolpropane di(meth)acrylate, glycerol di(meth)acrylate, bis(2-(meth)acryloyloxyethyl)hydroxyethyl isocyanurate and other triol mono- or di(meth)acrylates, or hydroxyl-containing mono- and di(meth)acrylates obtained by modifying a portion of these alcoholic hydroxyl groups with ε-caprolactone; compounds having a monofunctional hydroxyl group and a trifunctional or higher (meth)acryloyl group, such as pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, di-trimethylolpropane tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, or compounds obtained by modifying the above compounds with ε-caprolactone. (meth)acrylates having oxyalkylene chains, such as dipropylene glycol mono(meth)acrylate, diethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, and polyethylene glycol mono(meth)acrylate; (meth)acrylates having oxyalkylene chains, such as polyethylene glycol-polypropylene glycol mono(meth)acrylate and polyoxybutylene-polyoxypropylene mono(meth)acrylate; (meth)acrylates having random oxyalkylene chains, such as poly(ethylene glycol-tetramethylene glycol) mono(meth)acrylate and poly(propylene glycol-tetramethylene glycol) mono(meth)acrylate.

Urethane (meth)acrylate may use polyol as a reaction raw material in addition to polyisocyanate and (meth)acrylate having a hydroxyl group.

As the polyol, for example, polyether polyols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol, polyester polyols, and polycarbonate polyols can be used. These polyols can be used alone or in combination of two or more.

In multifunctional (meth)acrylate (C), compounds with urate skeletons can also be used. For example, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, bis (2-hydroxyethyl) isocyanurate di (meth) acrylate, and the starting materials of these compounds, i.e., hydroxyethyl (meth) acrylate, are changed to ethylene oxide (EO), propylene oxide, or ε-caprolactone modified bodies of hydroxyethyl (meth) acrylate. Compounds such as isocyanuric acid derivatives, urethane (meth) acrylates with urate skeletons, etc. are listed. Among them, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate is particularly preferred. Since tris (2-hydroxyethyl) isocyanurate di (meth) acrylate has a polar structure of hydroxyl and urate skeletons, it can promote the aggregation of hydrophobic organic microparticles (a-1) and further improve anti-glare properties.

These polyfunctional (meth)acrylates (C) may be used alone or in combination of two or more.

The content of the multifunctional (meth)acrylate (C) is preferably in the range of 20% to 85% by mass, more preferably in the range of 30% to 80% by mass, and particularly preferably in the range of 50% to 70% by mass, relative to the total amount of the radical polymerizable compound in the active energy ray-curable composition. By setting the content in the above range, both the transparency and the anti-glare property of the cured coating film can be improved in a well-balanced manner.

[Other ingredients]

The active energy ray-curable composition of the present invention may contain a photopolymerization initiator, a photosensitizer, a monofunctional (meth)acrylate compound, other additives, and the like, in addition to the components (A) to (C), as necessary.

The active energy ray-curable composition of the present invention can be formed into a hardened coating film by irradiating active energy rays after being applied to a substrate. The active energy ray refers to ionizing rays such as ultraviolet rays, electron beams, α rays, β rays, and γ rays. In the case of irradiating ultraviolet rays as active energy rays to form a hardened coating film, it is preferred to add a photopolymerization initiator to the active energy ray-curable composition of the present invention to improve the hardening property. In addition, if necessary, a photosensitizer may be further added to improve the hardening property. On the other hand, when using ionizing rays such as electron beams, α rays, β rays, and γ rays, even if a photopolymerization initiator or photosensitizer is not used, it will cure quickly, so there is no need to specifically add a photopolymerization initiator or photosensitizer.

As the photopolymerization initiator, for example, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropane-1-one, oligo {2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone}, benzyl dimethyl ketal, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-1-one, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenyl ketone, 2-methyl-2-morpholinyl (4-thiophene) phenyl ketone, Acetophenone compounds such as benzoin, benzoin methyl ether, benzoin isopropyl ether, etc.; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoin diphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; benzil (dibenzoyl), methylphenyl glyoxylate, oxyphenylacetic acid 2-(2-hydroxyethoxy)ethyl ester, oxyphenylacetic acid Benzyl compounds such as 2-(2-oxo-2-phenylacetoxyethoxy)ethyl ester; benzophenone, methyl-4-phenylbenzophenone, 4,4'-dichlorobenzophenone, hydroxybenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, acrylated benzophenone, 3,3',4,4'-tetra(tert-butylperoxycarbonyl)benzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 2,4,6-trimethylbenzophenone, 4-methylbenzophenone Benzophenone compounds such as ketone; 2-isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone and other thioxanthone compounds; aminobenzophenone compounds such as michler's ketone and 4,4'-diethylaminobenzophenone; 10-butyl-2-chloroacridone, 2-ethylanthraquinone, 9,10-phenanthrenequinone, camphorquinone, 1-[4-(4-benzoylphenylthio)phenyl]-2-methyl-2-(4-methylphenylsulfonyl)propane-1-one, etc. These photopolymerization initiators may be used alone or in combination of two or more.

Examples of the photosensitizer 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-benzylisothiouronium-p-toluenesulfonate.

The amount of the photopolymerization initiator and photosensitizer used is preferably 0.05 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, based on 100 parts by mass of the total amount of the radical polymerizable compound in the active energy ray-curable composition.

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, chlorophenyl (meth)acrylate, bromophenyl (meth)acrylate, chlorobenzyl (meth)acrylate, bromobenzyl (meth)acrylate, chlorophenyl ethyl (meth)acrylate, bromophenyl ethyl (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 Monofunctional (meth)acrylates having an aromatic ring, such as (meth)acrylate, 2,4,6-tribromobenzyl (meth)acrylate, 2,4,6-trichlorophenoxyethyl (meth)acrylate, 2,4,6-tribromophenoxyethyl (meth)acrylate, o-phenylphenol (poly)ethoxy (meth)acrylate, p-phenylphenol (poly)ethoxy (meth)acrylate; cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, tetrahydrofuran (meth)acrylate (Meth)acrylates having an alicyclic alkyl group such as furfuryl ester 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, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, octyl (meth)acrylate, dodecyl (meth)acrylate, and stearyl (meth)acrylate; styrene compounds such as styrene, α-methylstyrene, and chlorostyrene, etc.

As the other additives, for example, solvents, polymerization inhibitors, surface regulators, antistatic agents, defoamers, viscosity regulators, light stabilizers, weather stabilizers, heat stabilizers, ultraviolet light absorbers, antioxidants, leveling agents, organic pigments, inorganic pigments, pigment dispersants, additives such as microparticles other than (a-2) components; inorganic fillers such as silicon oxide, aluminum oxide, titanium oxide, zirconium oxide, antimony pentoxide, etc. can be used. These additives can be used alone or in combination of two or more. Among these, in terms of obtaining a more excellent anti-glare property, microparticles are preferably used.

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

The particle size of the microparticles is preferably in the range of 0.5 μm to 5 μm, more preferably in the range of 0.8 μm to 3.5 μm, and further preferably in the range of 1.0 μm to 2.5 μm, in terms of high cohesion and better anti-glare properties. In addition, the particle size of the microparticles represents the particle size when the cumulative amount accounts for 50% in the cumulative particle amount curve of the particle size distribution measurement result in the particle size distribution.

When the fine particles are used, the amount used is preferably in the range of 0.5 to 15% by mass, more preferably in the range of 1 to 7% by mass, in the active energy ray-curable composition from the viewpoint of obtaining more excellent anti-glare properties.

As the solvent, for example, methanol, ethanol, propanol, butanol, diacetone alcohol, isopropyl alcohol, diacetone alcohol, dimethyl carbitol, methyl acetate, ethyl acetate, propyl acetate, dimethyl carbonate, methyl ethyl ketone, methyl isobutyl ketone, acetone, acetylacetone, propylene glycol monomethyl ether acetate, ethylene glycol monomethyl ether, toluene, etc. can be used. These solvents can be used alone or in combination of two or more. Among these, isopropyl alcohol is preferably used in terms of obtaining more excellent transparency and anti-glare properties.

When the solvent is used, the amount used is preferably in the range of 40% by mass to 80% by mass in the active energy ray-curable composition in terms of coating properties and the like.

＜Hardened material＞

The cured product of the present invention is obtained by irradiating the active energy ray-curable composition of the present invention with active energy rays to cure it, and may be in any shape such as a film or a three-dimensional object.

As described above, the active energy rays for curing the active energy ray-curable composition of the present invention are ionizing rays such as ultraviolet rays, electron beams, α rays, β rays, and γ rays. Here, when ultraviolet rays are used as the active energy rays, the apparatus for irradiating the ultraviolet rays includes, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, an ultrahigh-pressure mercury lamp, a metal halide lamp, an electrodeless lamp (fusion lamp), a chemical lamp, a black light lamp, a mercury-xenon lamp, a short arc lamp, a helium-cadmium laser, an argon laser, sunlight, and a light emitting diode (LED) lamp.

＜Film＞

The film of the present invention is obtained by applying the active energy ray-curable composition of the present invention on at least one surface of a film substrate and then irradiating the substrate with active energy rays to form a cured coating film.

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; cellulose resins such as cellulose acetate (diacetyl cellulose, triacetyl cellulose, etc.), cellulose acetate propionate, cellulose acetate butyrate, cellulose acetate propionate butyrate, cellulose acetate phthalate, and cellulose nitrate; acrylic resins such as polymethyl methacrylate; polyvinyl chloride, polyvinylidene chloride, and the like. Vinyl chloride resins such as ethylene; polyvinyl alcohol; ethylene-vinyl acetate copolymers; polystyrene; polyamide; polycarbonate; polysulfone; polyethersulfone; polyetheretherketone; polyimide resins such as polyimide and polyetherimide; norbornene resins (for example, "Zeonor" manufactured by ZEON Co., Ltd. of Japan), modified norbornene resins (for example, "Arton" manufactured by JSR Co., Ltd.), cyclic olefin copolymers (for example, "Apel" manufactured by Mitsui Chemicals Co., Ltd.), etc. Furthermore, a substrate formed by laminating two or more substrates containing these resins can also be used.

Furthermore, in the present invention, by using the active energy ray-curable composition, even when polymethyl methacrylate is used as the film substrate, a hard coating layer having excellent antiglare properties and antistatic properties can be formed.

The polymethyl methacrylate substrate (hereinafter referred to as "PMMA") is a substrate formed of a polymer having polymethyl methacrylate as a main component (preferably 100% by mass), and can be obtained as commercially available products such as "Technolloy S014G", "Technolloy S001G", and "Technolloy S000" manufactured by Sumitomo Chemical Co., Ltd., "Acryplen HBS006", "Acryplen HBXN47", and "Acryplen HBS010" manufactured by Mitsubishi Chemical Co., Ltd., and "Panlite Film PC-2151" manufactured by Teijin Chemicals Co., Ltd.

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 μm to 500 μm. In addition, when a film-like substrate film is used, its thickness is preferably in the range of 20 μm to 200 μm, more preferably in the range of 30 μm to 150 μm, and further preferably in the range of 40 μm to 130 μm. By setting the thickness of the film substrate to the above range, even when a hard coating layer is provided on one side of the film using the active energy ray-curable composition of the present invention, curling is easily suppressed.

Examples of a method for applying the active energy ray-curable composition of the present invention to the film substrate include die coating, micro gravure coating, gravure coating, roll coating, notch wheel coating, air knife coating, kiss coating, spray coating, dip coating, spinner coating, brush coating, full screen coating using a screen, wire bar coating, and flow coating.

In order to volatilize the solvent after applying the active energy ray-curable composition on the substrate film and before irradiating the active energy ray, it is preferably dried by heating or at room temperature. As the conditions for heating and drying, for example, heating and drying at a temperature in the range of 50° C. to 100° C. and for a time in the range of 0.5 minutes to 10 minutes can be cited.

In order to ensure sufficient hardness of the cured coating film and suppress curling of the film due to curing shrinkage of the coating film, the film thickness of the cured coating film when the cured coating film of the active energy ray-curable composition of the present invention is formed on the film substrate is preferably in the range of 1 μm to 30 μm, more preferably in the range of 3 μm to 15 μm, and even more preferably in the range of 4 μm to 10 μm.

As described above, the active energy ray-curable composition of the present invention can form a hard coating layer having excellent coating stability, coating film appearance, and anti-glare properties on various substrates including polymethyl methacrylate substrates.

Therefore, a film having a hard coat layer comprising a cured coating film of the active energy ray-curable composition of the present invention can be suitably used as an optical film used in flat panel displays (FPD) such as liquid crystal displays (LCDs), organic EL displays (OLEDs), and plasma displays (PDPs).

[Example]

Hereinafter, the present invention will be described in more detail with reference to examples.

[Example 1]

55 parts by mass of a multifunctional monomer (a mixture of pentaerythritol tetraacrylate and pentaerythritol triacrylate), 70 parts by mass of an epoxy acrylate (a reaction product of polyglycidyl methacrylate and acrylic acid, solid content 50%, diluted with methyl isobutyl ketone), 10 parts by mass of an isocyanuric acid EO-modified diacrylate urethane acrylate ("Aronix M215" manufactured by Toagosei Co., Ltd.), and a dispersant (a-1) ("DISPERBYK" manufactured by BYK-chemie) were mixed with a molten-crystal column. -109”), 3.0 parts by mass of a mixed solvent (dimethyl carbonate/MIBK/IPA/propyl acetate/methyl acetate/1,3-dioxolane=20.1/22.6/65.4/39.0/9.7/4.5), and 5 parts by mass of a photoinitiator (1-hydroxycyclohexyl phenyl ketone) were fully mixed, and then 4.4 parts by mass of organic microparticles (microparticles composed of polymethyl methacrylate, refractive index 1.51, average particle size 2.0 μm) were mixed to prepare an active energy ray-curable composition having a non-volatile content of 36.8% by mass.

[Example 2 to Example 4 and Comparative Example 2 to Comparative Example 4]

An active energy ray-curable composition was prepared in the same manner as in Example 1 except that the formulation was changed to that shown in Table 1, and then an evaluation film was prepared and evaluated.

[Preparation of samples for evaluation]

The active energy ray-curable composition was applied to a PMMA film having a thickness of 60 μm using a bar coater in a manner such that the film thickness became 5 μm. After drying at 60° C. for 1 minute, the film was irradiated twice under a nitrogen atmosphere using an ultraviolet irradiation device (manufactured by Eye Graphics Co., Ltd., a high-pressure mercury lamp) at an irradiation light dose of 75 mJ/m ² to obtain a PMMA film having a cured coating as an evaluation sample.

[Evaluation of haze]

The obtained evaluation film was measured under D65 light source using a haze meter ("NDH4000" manufactured by Nippon Denshoku Co., Ltd.) in accordance with Japanese Industrial Standards (JIS) K7136. The smaller the haze value, the better the anti-glare property, and a range of 2.0% to 3.0% was considered acceptable.

[Evaluation of total light transmittance]

The evaluation film obtained as described above was measured in accordance with JIS K7361-1. The higher the total light transmittance, the higher the transparency, and 90% or more was considered acceptable.

[Through the evaluation of clarity]

According to JIS K7374, the obtained evaluation film was measured using an image writing measuring instrument ("ICM-1T" manufactured by Suga Testing Machine Co., Ltd.) at four points of optical comb width 0.125 mm, 0.5 mm, 1.0 mm, and 2.0 mm. The total value of the measured four points was used for evaluation. If the total value is high, the anti-glare property is weak, and if the total value is low, the anti-glare property is too strong and the visibility of the screen is reduced, so the range of 310%-355% is set as qualified.

[Evaluation results]

Table 1 shows the results.

The abbreviations in the table are as follows.

Organic microparticles (a-1): microparticles composed of polymethyl methacrylate, average primary particle diameter 2.0 μm, refractive index 1.51

DISPERBYK-109: Alkyl alcohol amino amide, manufactured by BYK-chemie

DISPERBYK-180: Alkyl alcohol ammonium salt of a copolymer containing acid groups, manufactured by BYK-chemie

DISPERBYK-U100: Salt of unsaturated polyaminoamide and low molecular weight polyester acid, manufactured by BYK-chemie

DISPERBYK-102: A copolymer with an acidic group, manufactured by BYK-chemie

DISPERBYK-103: A copolymer with affinity for pigments, manufactured by BYK-chemie

Epoxy (meth)acrylate (B): a methyl isobutyl ketone solution of a reaction product of polyglycidyl methacrylate and acrylic acid (solid content 50%), viscosity 1000 mPa·s

M305: Pentaerythritol tetraacrylate (containing 55%-63% pentaerythritol triacrylate), manufactured by Toa Gosei Co., Ltd. under the trade name "Aronix M-305"

M215: Isocyanuric acid EO modified diacrylate, manufactured by Toagosei Co., Ltd. under the trade name "Aronix M-215"

R-1104: 1-Hydroxycyclohexyl phenyl ketone, manufactured by RUNTEC Chemical under the trade name “RUNTECURE 1104”

From the evaluation results shown in Table 1, it is understood that the cured coating films of the active energy ray-curable compositions of the present invention in Examples 1 to 4 have excellent transparency and anti-glare properties.

On the other hand, in Comparative Example 1 shown in Table 1, the dispersant (a-2) was not contained, and the transparency of the cured coating film was reduced.

In addition, Comparative Examples 2 to 4 shown in Table 1 are embodiments in which an alkanolamine compound is not used as a dispersant. In these Comparative Examples, the transparency of the cured coating film is also reduced.

Claims (8)

1. An active energy ray-curable composition comprising: organic microparticle dispersion (A) and epoxy (meth) acrylate (B),

the organic microparticle dispersion (A) contains organic microparticles (a-1) and a dispersant (a-2),

the dispersant (a-2) is an alkanolamine compound.

2. The active energy ray-curable composition according to claim 1, wherein the organic fine particles (a-1) have an average primary particle diameter in the range of 0.5 μm to 3 μm.

3. The active energy ray-curable composition according to claim 1, wherein the dispersant (a-2) has an amine value of 80mgKOH/g or more.

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

5. The active energy ray-curable composition according to claim 1, further comprising a polyfunctional (meth) acrylate (C) different from the epoxy (meth) acrylate (B).

6. The active energy ray-curable composition according to claim 5, wherein the multifunctional (meth) acrylate (C) is a compound having a urethane skeleton in a molecule.

7. A cured product of the composition according to any one of claims 1 to 6.

8. A film, characterized in that: a cured coating film comprising the composition according to any one of claims 1 to 6.