JP5763874B2 - Coating composition and optical film using the same - Google Patents

Description

  The present invention relates to a coating composition excellent in coatability and an optical film using the same.

  2. Description of the Related Art Conventionally, in a liquid crystal display device used for a personal computer or the like, a backlight unit is arranged behind the liquid crystal display panel so that the display image can be easily seen, and light from the backlight unit is supplied to the liquid crystal display panel side. In general, an image is displayed by doing so. As one of the components of a backlight unit used in a liquid crystal display device, a light diffusing member that supplies as much light as possible to the liquid crystal display panel side is used.

  Various light diffusing members used as components of the backlight unit have been proposed. For example, a light diffusing plate formed from an optical resin composition containing fine particles made of an organic material or an inorganic material, There has been proposed a light diffusion film in which inorganic fine particles or resin fine particles are coated on the surface of a transparent or translucent substrate via a binder resin.

  As an optical resin composition used as the material of the light diffusing plate, for example, in Patent Document 1, 0.5 to 10 weight of a light diffusing agent having a weight average particle diameter of 1 to 20 μm is added to 100 parts by weight of a methyl methacrylate resin. And a methyl methacrylate-based light diffusing resin composition obtained by adding and dispersing a part and a surfactant in a ratio of 0.005 to 0.5 by weight with respect to the light diffusing agent 1. Patent Document 1 describes that when a specific amount of a surfactant is dispersed with respect to a light diffusing agent dispersed in a base resin, whitening does not occur during stretching.

Further, an anti-glare member that diffuses surface reflected light and prevents reflection of external light is used on the surface of the liquid crystal display device in order to improve the visibility of the image. As such an antiglare member, an antiglare film in which inorganic fine particles or resin fine particles are coated on a transparent or translucent substrate surface via a binder resin has been proposed (for example, Patent Document 2). .
JP 2001-11277 A JP-A-10-020103

  However, the optical resin composition described in Patent Document 1 has been developed on the assumption that a light diffusion sheet is formed by extrusion molding or injection molding using the optical resin composition. Therefore, when the optical resin composition described in Patent Document 1 is used to produce a light diffusion film or an antiglare film by coating the optical resin composition on the surface of a transparent or translucent substrate, The applicability of the optical resin composition has not been studied.

  The present invention has been made in view of the above circumstances, and an object of the present invention is a coating composition containing organic particles and a surfactant and having excellent coating properties, and It is to provide organic particles useful for obtaining such a coating composition.

The coating composition of the present invention that has solved the above problems is a coating composition containing organic particles and a surfactant, and the content of the surfactant is relative to the organic particles. 550 ppm to 2000 ppm . By setting the surfactant content in the coating composition within a predetermined range, the viscosity characteristics of the coating composition can be adjusted, and the coating properties of the coating composition can be improved.

  The organic particles are preferably organic polymer particles obtained by polymerizing the monomer composition. The monomer composition preferably includes a monomer mixture containing a vinyl monomer, and the monomer mixture preferably contains 1% by mass to 50% by mass of a crosslinkable monomer. . As the organic particles, organic-inorganic composite particles having an organic polymer skeleton and a polysiloxane skeleton are also suitable.

  The surfactant contained in the coating composition of the present invention is preferably an anionic surfactant. Moreover, it is preferable that the said surfactant remains in the said organic particle. The coating composition of the present invention preferably further contains a binder resin, and further preferably contains a crosslinking agent component.

Furthermore, the present invention includes organic particles used in the coating composition. Such organic particles preferably contain 550 ppm to 2000 ppm of a surfactant. Further, an antiglare film having a substrate film and an antiglare layer formed from the coating composition on at least one surface of the substrate film, and a substrate film and at least one surface of the substrate film A light diffusion film having a light diffusion layer formed from the coating composition is a preferred embodiment of the present invention.

  According to the present invention, a coating composition having excellent coating properties and organic particles useful for such a coating composition can be obtained. Moreover, the anti-glare film which has a uniform anti-glare layer, or the light-diffusion film which has a uniform light-diffusion layer is obtained by using the coating composition of this invention.

  The coating composition of the present invention is a coating composition containing organic particles and a surfactant, wherein the content of the surfactant is 500 ppm to 2000 ppm with respect to the organic particles. It is said. In addition, in this invention, ppm shall show the mass parts per million.

Surfactant The surfactant used in the coating composition of the present invention will be described. Examples of the surfactant include an anionic surfactant; a cationic surfactant; an amphoteric surfactant; a nonionic surfactant; and a water-soluble polymer.

  Examples of anionic surfactants include fatty acid oils such as sodium oleate and castor oil potassium; alkyl sulfate salts such as sodium lauryl sulfate and ammonium lauryl sulfate; polyoxyethylene distyryl phenyl ether sulfate ammonium salt and polyoxyethylene distyryl Polyoxyethylene distyryl phenyl ether sulfate such as phenyl ether sulfate sodium salt; Alkyl benzene sulfonate such as sodium dodecylbenzene sulfonate; Alkyl naphthalene sulfonate, alkane sulfonate, dialkyl sulfosuccinate, alkyl phosphate Ester salt, naphthalenesulfonic acid formalin condensate, polyoxyethylene alkylphenyl ether sulfate ester salt, polyoxyethylene alkyl Such ester salts.

  Examples of the cationic surfactant include alkylamine salts such as laurylamine acetate and stearylamine acetate; quaternary ammonium salts such as lauryltrimethylammonium chloride. Examples of the zwitterionic surfactant include lauryl dimethylamine oxide. Nonionic surfactants include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin fatty acid ester, oxyethylene- Examples thereof include oxypropylene block polymers. Examples of the water-soluble polymer include polyvinyl alcohol, gelatin, tragacanth, starch, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, sodium polyacrylate, and sodium polymethacrylate.

  The said surfactant may be used independently and may use 2 or more types together. Among these, alkyl sulfate esters such as sodium lauryl sulfate and ammonium lauryl sulfate; polyoxyethylene distyryl phenyl ether sulfate such as polyoxyethylene distyryl phenyl ether sulfate ammonium salt and polyoxyethylene distyryl phenyl ether sulfate sodium salt Anionic surfactants such as ester salts are preferred.

The content of the surfactant, 550 ppm or more with respect to organic particles, good Mashiku is 650ppm or more, more preferably 1000ppm or more. By setting the content of the surfactant to 550 ppm or more with respect to the organic particles, it is possible to prevent sedimentation of the organic particles in the coating composition, so that the storage stability of the coating composition is improved and the coating composition is improved. When the composition is applied to a substrate film or the like, a uniform coated surface can be obtained without unevenness. Moreover, content of the said surfactant is 2000 ppm or less with respect to the said organic particle, Preferably it is 1800 ppm or less, More preferably, it is 1600 ppm or less. By setting the content of the surfactant to 2000 ppm or less with respect to the organic particles, the leveling property of the coating composition is improved. Therefore, when the coating composition is applied to a base film or the like, unevenness occurs. A uniform coated surface can be obtained.

  The surfactant may be added when preparing the coating composition. However, when organic polymer particles or organic-inorganic composite particles as described later are used as the organic particles constituting the coating composition, these surfactants are used. Surfactant used as a dispersion stabilizer, emulsifier, etc. when polymerizing organic polymer particles or organic-inorganic composite particles of the present invention, and the surfactant remaining in the produced organic particles as it is, constitutes the coating composition as it is It is preferable to use as. In particular, it is preferable to use only the surfactant remaining in the organic particles as the surfactant constituting the coating composition.

  The surfactant content relative to the organic particles in the coating composition can be measured by ion chromatography or the like. As described above, when only the surfactant remaining in the organic particles is used as the surfactant that constitutes the coating composition, the surfactant content of the organic particles remains as it is in the coating composition. This is the surfactant content relative to the particles.

Organic Particles The organic particles used in the coating composition of the present invention will be described. The organic particles used in the coating composition of the present invention are not particularly limited as long as they contain an organic component. Organic polymer particles made of an organic polymer or organic / inorganic made of a material in which organic and inorganic materials are combined. Any of the composite particles can be used.

Organic polymer particles Examples of the organic polymer particles include vinyl polymer particles, ester polymer particles, ether polymer particles, and amide polymer particles. These organic polymer particles may be used alone or in combination of two or more. Among these organic polymer particles, the organic polymer particles used in the present invention include a vinyl polymer obtained by polymerizing a monomer composition containing a monomer mixture containing a vinyl monomer. Particles are preferred.

  The vinyl monomer contained in the monomer mixture is a non-crosslinkable monomer having one vinyl group in one molecule, and a crosslinkable monomer having two or more vinyl groups in one molecule. Any of the bodies can be used.

  Examples of the non-crosslinkable monomer include (meth) acrylic acid; (meth) methyl acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) Isobutyl acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, (meth) (Meth) acrylic acid esters such as dodecyl acrylate, glycidyl (meth) acrylate, cyclohexyl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate; (meth) acrylic acid 2 -Hydroxyethyl, 2-hydroxypropyl (meth) acrylate, 2-hydroxy (meth) acrylate (Meth) acrylic monomers such as (meth) acrylic acid such as chill; methacrylic monomers such as: styrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, α-methylstyrene, p-methoxystyrene, p -Styrenic monomers such as tert-butylstyrene, p-phenylstyrene, o-chlorostyrene, m-chlorostyrene, p-chlorostyrene, parahydroxystyrene: 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, etc. Hydroxyl group-containing vinyl ethers: Examples include hydroxyl group-containing allyl ethers such as 2-hydroxyethyl allyl ether and 4-hydroxybutyl allyl ether. These non-crosslinkable monomers may be used alone or in combination of two or more. Among these non-crosslinkable monomers, (meth) acrylic monomers such as methyl (meth) acrylate, n-butyl (meth) acrylate, hexyl (meth) acrylate; styrene-based monomers such as styrene A mer is preferred.

  Examples of the crosslinkable monomer include trimethylolpropane triacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, decaethylene glycol dimethacrylate, pentadecaethylene glycol dimethacrylate, pentacontact ethylene glycol dimethacrylate. Polyfunctional (meth) acrylates such as methacrylate, 1,3-butylene dimethacrylate, allyl methacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate; aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene, and derivatives thereof; N, N-divinylaniline, divinyl ether, divinyl sulfide, divinyl sulfonic acid What crosslinking agent; polybutadiene, poly isoprene unsaturated polyesters. These crosslinkable monomers may be used alone or in combination of two or more. Among these, polyfunctional (meth) acrylates such as ethylene glycol dimethacrylate and diethylene glycol dimethacrylate are preferable.

  The content of the crosslinkable monomer in the monomer mixture is preferably 1% by mass or more, more preferably 5% by mass or more, still more preferably 10% by mass or more, and 50% by mass or less. More preferably, it is 40 mass% or less, More preferably, it is 30 mass% or less. By setting the content of the crosslinkable monomer in the monomer mixture to 1% by mass or more, it is possible to prevent the organic particles from swelling in the solvent in the coating composition and the coating composition from solidifying into a gel. Moreover, sedimentation of organic particles in the coating composition can be prevented by setting the content of the crosslinkable monomer to 50% by mass or less.

  Further, when the monomer composition is polymerized, a polymerization initiator or a dispersion stabilizer may be used as necessary.

  As the polymerization initiator, any of those usually used for polymerization can be used. For example, a peroxide initiator, an azo initiator, or the like can be used. Examples of the peroxide initiator include hydrogen peroxide, peracetic acid, benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, orthochlorobenzoyl peroxide, orthomethoxybenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide. Oxide, t-butylperoxy-2-ethylhexanoate, di-t-butyl peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, methyl ethyl ketone peroxide, diisopropyl Examples include peroxydicarbonate, cumene hydroperoxide, cyclohexanone peroxide, t-butyl hydroperoxide, and diisopropylbenzene hydroperoxide. Examples of the azo initiator include dimethyl 2,2-azobisisobutyronitrile, azobiscyclohexacarbonitrile, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethyl). Valeronitrile), 2,2′-azobis (2,3-dimethylbutyronitrile), 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,3,3-trimethyl) Butyronitrile), 2,2′-azobis (2-isopropylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (4-methoxy-2,4- Dimethylvaleronitrile), 2- (carbamoylazo) isobutyronitrile, 2,2′-azobis (2-amidinopropane) dihydrochloride, 4,4′-azobis (4-cyanope) Tan acid), 4,4'-azobis (4-cyanovaleric acid), dimethyl-2,2'-azo-bis-isobutyrate and the like.

  These polymerization initiators may be used alone or in combination of two or more. The addition amount of these polymerization initiators is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, and 5 parts by mass or less with respect to 100 parts by mass of the monomer mixture. It is preferable that it is 3 parts by mass or less.

  The dispersion stabilizer is used to stabilize the droplet diameter of the monomer composition during the polymerization reaction when the monomer composition is polymerized using a suspension polymerization method or the like. . The dispersion stabilizer may be dissolved or dispersed in a solvent (for example, an aqueous solvent) as a dispersion medium without being contained in the monomer composition. Examples of the dispersion stabilizer include those exemplified as the surfactant constituting the coating composition. The said dispersion stabilizer may be used independently and may use 2 or more types together. Among these, as the dispersion stabilizer, an anionic surfactant is preferable.

  What is necessary is just to adjust the addition amount of the said dispersion stabilizer suitably according to the size of the desired organic polymer particle. For example, if it is desired to obtain organic polymer particles having an average particle diameter of 3 μm or more and 30 μm or less, the amount of dispersion stabilizer added is preferably 0.1 parts by mass or more with respect to 100 parts by mass of the monomer mixture. More preferably, it is 0.5 parts by mass or more, more preferably 1 part by mass or more, and preferably 10 parts by mass or less, more preferably 5 parts by mass or less, still more preferably 3 parts by mass or less.

  Furthermore, pigments, plasticizers, polymerization stabilizers, fluorescent brighteners, magnetic powders, ultraviolet absorbers, antistatic agents, flame retardants and the like may be added to the monomer composition. The amount of these additives used is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and still more preferably 0.5 parts by mass or more with respect to 100 parts by mass of the monomer mixture. It is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and still more preferably 3 parts by mass or less.

Method for Producing Organic Polymer Particles Next, a method for producing organic polymer particles will be described. The method for producing organic polymer particles used in the present invention polymerizes a monomer composition containing the monomer mixture as described above. In addition, as a polymerization method, well-known polymerization methods, such as suspension polymerization, seed polymerization, and emulsion polymerization, can be employ | adopted, Among these, suspension polymerization and seed polymerization are preferable.

  When employing the suspension polymerization method, the solvent used is not particularly limited as long as it does not completely dissolve the monomer composition, but an aqueous medium is preferably used. These solvents can be appropriately used within a range of usually 20 parts by mass or more and 10,000 parts by mass or less with respect to 100 parts by mass of the monomer composition. As a method for producing organic polymer particles, a monomer composition containing the monomer mixture and the polymerization initiator is suspended in an aqueous solvent in which the dispersion stabilizer is dissolved or dispersed and polymerized. The method is preferred.

  The polymerization temperature of the suspension polymerization is preferably 50 ° C. or higher, more preferably 55 ° C. or higher, further preferably 60 ° C. or higher, preferably 95 ° C. or lower, more preferably 90 ° C. or lower, Preferably it is 85 degrees C or less. The polymerization time for the suspension polymerization is preferably 1 hour or more, more preferably 2 hours or more, further preferably 3 hours or more, and preferably 10 hours or less, more preferably 8 hours. Hereinafter, it is more preferably 5 hours or less. In order to control the particle diameter of the organic polymer resin to be produced, it is preferable that the polymerization reaction is performed after regulating the droplet diameter of the monomer composition or while regulating the droplet diameter. . The regulation of the droplet diameter of the monomer composition is, for example, that a suspension in which the monomer composition is dispersed in an aqueous medium is changed to T.P. K. It can be carried out by stirring with a high-speed stirrer such as a homomixer or a line mixer. And the organic polymer particle produced | generated by the polymerization reaction may be used for processes, such as drying and classifying as needed. In addition, it is preferable to perform drying at 150 degrees C or less, More preferably, it is 120 degrees C or less, More preferably, it is 100 degrees C or less.

  When employing the seed polymerization method, it is preferable to use a styrene-based or (meth) acrylic acid ester-based polymer as the seed particle, and it is more preferable that the seed particle be non-crosslinked. The average particle diameter of the seed particles is preferably 0.1 μm to 10 μm, and the value (Cv value) represented by 100 × particle diameter standard deviation / average particle diameter is preferably 10 or less. As a method for producing such seed particles, a conventionally used method can be employed, and examples thereof include soap-free emulsion polymerization and dispersion polymerization.

  The charged amount of the monomer composition in the seed polymerization is preferably 0.5 to 50 parts by mass with respect to 1 part by mass of the seed particles. If the charged amount of the monomer composition is too small, the increase in the particle size due to polymerization is small, and if it is too large, the monomer composition is not completely absorbed by the seed particles and polymerizes independently in the medium. May produce abnormal particles. In addition, about the polymerization temperature and the drying conditions of the obtained particle | grains, the conditions similar to the said suspension polymerization are applicable.

Organic-inorganic composite particles Organic-inorganic composite particles are particles comprising an organic part and an inorganic part. As an aspect of the organic-inorganic composite particles, an aspect in which inorganic fine particles such as metal oxides such as silica, alumina and titania, metal nitrides, metal sulfides and metal carbides are dispersed and contained in an organic resin; (organo ) A mode in which a metalloxane chain (a molecular chain containing a “metal-oxygen-metal” bond) such as polysiloxane and polytitanoxane and an organic molecule are combined at the molecular level; hydrolysis and condensation of an organoalkoxysilane such as methyltrimethoxysilane An aspect like silicone-based particles such as polymethylsilsesquioxane obtained by the progress of the reaction; having a polysiloxane made from a silicon compound having a hydrolyzable silyl group and a polymerizable group (for example, vinyl group) Includes an organic polymer skeleton obtained by reacting with a polymerizable monomer and the like, and a polysiloxane skeleton Such embodiments consisting machine and inorganic composite materials. Among these, an embodiment comprising an organic polymer skeleton and a polysiloxane skeleton is particularly preferable.

  Hereinafter, organic-inorganic composite particles (hereinafter, simply referred to as “composite particles”) made of an organic-inorganic composite material containing an organic polymer skeleton and a polysiloxane skeleton will be described in detail.

  The organic polymer skeleton may have a side chain, a branched structure, or a crosslinked structure. The molecular weight, composition, structure, presence / absence of functional groups, etc. of the organic polymer forming the skeleton are not particularly limited. Examples of the organic polymer include (meth) acrylic resins, vinyl polymers such as polystyrene and polyolefin, polyamides such as nylon, polyimide, polyester, polyether, polyurethane, polyurea, polycarbonate, phenol resin, melamine resin, In addition, at least one selected from the group consisting of urea resins is preferable.

  As the form of the organic polymer skeleton, a polymer having a main chain composed of a repeating unit represented by the following formula (1) (so-called vinyl polymer) because the hardness of the composite particles can be appropriately controlled. ) Is preferable.

  The polysiloxane skeleton is defined as a compound in which a siloxane unit represented by the following formula (2) is continuously chemically bonded to form a network of a network structure.

The amount of SiO ₂ constituting the polysiloxane skeleton is preferably 0.1% by mass or more, more preferably 1% by mass or more, and preferably 25% by mass or less based on the weight of the composite particles. More preferably, it is 10 mass% or less. When the amount of SiO ₂ in the polysiloxane skeleton is in the above range, the hardness of the composite particles can be easily controlled. The amount of SiO ₂ constituting the polysiloxane skeleton is a mass percentage obtained by measuring the mass before and after firing the particles at a temperature of 800 ° C. or higher in an oxidizing atmosphere such as air.

  The composite particles can be arbitrarily adjusted by appropriately changing the ratio of the polysiloxane skeleton portion or the organic polymer skeleton portion with respect to each of mechanical properties such as hardness and breaking strength. The polysiloxane skeleton in the composite particles is preferably obtained by a hydrolysis condensation reaction of a silicon compound having a hydrolyzable group.

  Although it does not specifically limit as said silicon compound which has the hydrolysability, For example, the silicon compound represented by following General formula (3), its derivative (s), etc. are mentioned.

R ' _m SiX _4-m (3)
(In the formula, R ′ may have a substituent and represents at least one group selected from the group consisting of an alkyl group, an aryl group, an aralkyl group and an unsaturated aliphatic group, and X represents a hydroxyl group, an alkoxy group. And represents at least one group selected from the group consisting of a group and an acyloxy group, and m is an integer from 0 to 3.)

  The silicon compound represented by the general formula (3) is not particularly limited, but examples of m = 0 include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, and the like. Functional silanes: those with m = 1 include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, phenyltrimethoxysilane, benzyltrimethoxy Silane, naphthyltrimethoxysilane, methyltriacetoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, 3- (meth) acryloxy Trifunctional silanes such as propyltrimethoxysilane and 3,3,3-trifluoropropyltrimethoxysilane; m = 2 include dimethyldimethoxysilane, dimethyldiethoxysilane, diacetoxydimethylsilane, and diphenylsilanediol. Examples of bifunctional silanes such as m = 3 include monofunctional silanes such as trimethylmethoxysilane, trimethylethoxysilane, and trimethylsilanol.

  Among these, in the general formula (3), a silicon compound having a structure in which m is 1, X is a methoxy group or an ethoxy group, and a refractive index is 1.30 or more and 1.60 or less is an optical application. It is preferable because composite particles having a refractive index suitable for the above can be obtained. Specifically, methyltrimethoxysilane, phenyltrimethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3,3,3-trifluoro And propyltrimethoxysilane.

  The derivative of the silicon compound represented by the general formula (3) is not particularly limited. For example, a part of X is substituted with a group capable of forming a chelate compound such as a carboxyl group and a β-dicarbonyl group. And low condensates obtained by partially hydrolyzing the silane compound.

  The silicon compound having hydrolyzability may be used alone or in combination of two or more. In the general formula (3), composite particles cannot be obtained when only the silicon compound with m = 3 and its derivatives are used as raw materials.

  When the composite particle has a polysiloxane skeleton having an organic silicon atom in which a silicon atom is directly bonded to at least one carbon atom in the organic polymer skeleton, the hydrolyzable silicon compound. It is necessary to use those having an organic group containing a polymerizable reactive group capable of forming an organic polymer skeleton. Examples of the reactive group include a radical polymerizable group, an epoxy group, a hydroxyl group, and an amino group. Is mentioned.

  Examples of the organic group containing the radical polymerizable group include radical polymerizable groups represented by the following general formulas (4), (5), and (6).

^{_{CH 2 = C (-R a)}} -COOR b - (4)
(In the formula, R ^a represents a hydrogen atom or a methyl group, and R ^b represents a C 1-20 divalent organic group which may have a substituent.)
^{_{CH 2 = C (-R c)}} - (5)
(In the formula, R ^c represents a hydrogen atom or a methyl group.)
^{_{CH 2 = C (-R d)}} -R e - (6)
(In the formula, R ^d represents a hydrogen atom or a methyl group, and R ^e represents a C 1-20 divalent organic group which may have a substituent.)

  Examples of the radical polymerizable group-containing organic group of the general formula (4) include an acryloxy group and a methacryloxy group. Examples of the silicon compound of the general formula (3) having the organic group include γ- Methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropyltriethoxysilane, γ-methacryloxypropyltriacetoxysilane, γ-methacryloxyethoxypropyltri Methoxysilane (or γ-trimethoxysilylpropyl-β-methacryloxyethyl ether), γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxypropylmethyl Examples thereof include rudimethoxysilane. These may be used alone or in combination of two or more.

  Examples of the radical polymerizable group-containing organic group of the general formula (5) include a vinyl group and an isopropenyl group. Examples of the silicon compound of the general formula (3) having the organic group include vinyl. Examples include trimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, and vinylmethyldiacetoxysilane. These may be used alone or in combination of two or more.

  Examples of the radical polymerizable group-containing organic group of the general formula (6) include a 1-alkenyl group or a vinylphenyl group, an isoalkenyl group, an isopropenylphenyl group, and the like. Examples of the silicon compound 3) include 1-hexenyltrimethoxysilane, 1-hexenyltriethoxysilane, 1-octenyltrimethoxysilane, 1-decenyltrimethoxysilane, γ-trimethoxysilylpropyl vinyl ether, ω- Examples include trimethoxysilylundecanoic acid vinyl ester, p-trimethoxysilylstyrene, 1-hexenylmethyldimethoxysilane, 1-hexenylmethyldiethoxysilane, and the like. These may be used alone or in combination of two or more.

  Examples of the silicon compound having an organic group containing an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane and the like. These may be used alone or in combination of two or more. Examples of the silicon compound having an organic group containing a hydroxyl group include 3-hydroxypropyltrimethoxysilane. These may be used alone or in combination of two or more.

  Examples of the silicon compound having an organic group containing an amino group include N-β (aminoethyl) γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, and N-β. (Aminoethyl) γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane and the like can be mentioned. These may be used alone or in combination of two or more.

  The organic polymer skeleton contained in the composite particle is (I) after a polymerizable monomer having a polymerizable reactive group is absorbed in a particle having a polysiloxane skeleton obtained by hydrolysis condensation reaction of a silicon compound. Can be obtained by polymerization. In particular, when the silicon compound has an organic group containing a polymerizable reactive group such as a radically polymerizable group together with a hydrolyzable group, (II) the polymer is polymerized after the hydrolysis condensation reaction of the silicon compound. You can get it.

  The composite particles are (i) a form (chemical bond type) in which the polysiloxane skeleton has an organosilicon atom in which a silicon atom is directly chemically bonded to at least one carbon atom in the organic polymer skeleton. There may be (ii) the form (IPN type) which does not have such an organosilicon atom in a molecule | numerator, Although it does not specifically limit, the form of (i) is preferable. When the organic polymer skeleton is obtained together with the polysiloxane skeleton by the method (I), composite particles having the form (ii) are obtained. In particular, the silicon compound is radically polymerized together with the hydrolyzable group. If it has an organic group containing a polymerizable reactive group such as a functional group or an epoxy group, composite particles having both the forms of (i) and (ii) can be obtained. Further, when the organic polymer skeleton is obtained together with the polysiloxane skeleton as in (II), composite particles having the form (i) are obtained.

  In the methods (I) and (II), the radical polymerizable monomer that can be absorbed by the particles having a polysiloxane skeleton is a monomer mixture that essentially contains a radical polymerizable vinyl monomer. Preferably there is. The radical polymerizable vinyl monomer is not particularly limited as long as it is a compound containing at least one ethylenically unsaturated group in the molecule, and the physical properties of the desired composite particles are not limited. It can be appropriately selected depending on the case. These may be used alone or in combination of two or more.

  For example, a hydrophobic radical-polymerizable vinyl monomer can generate a stable emulsion in which the monomer mixture is emulsified and dispersed when the monomer mixture is absorbed by particles having a polysiloxane skeleton. Therefore, it is preferable. Further, as the radical polymerizable vinyl monomer, a crosslinkable monomer may be used. If a crosslinkable monomer is used, the mechanical properties of the resulting composite particles can be easily adjusted, The solvent resistance of the composite particles can also be improved. As the crosslinkable monomer, those exemplified as those used for the organic polymer particles can be used.

  The method for producing the composite particles preferably includes a hydrolysis and condensation step and a polymerization step, and includes an absorption step for absorbing the polymerizable monomer after the hydrolysis and condensation step and before the polymerization step. More preferred. By including the absorption step, the content of the organic polymer skeleton component in the organic-inorganic composite particles and the refractive index of the organic polymer skeleton contained can be adjusted, so that the resulting organic-inorganic composite particles in the coating composition Dispersibility and the refractive index of organic-inorganic composite particles can be adjusted. In addition, when the silicon compound used in the hydrolysis and condensation process does not have an element that constitutes an organic polymer skeleton together with an element that can constitute a polysiloxane skeleton structure, the absorption process is indispensable. In the subsequent polymerization step, an organic polymer skeleton is formed.

  The hydrolysis and condensation step is a step of performing a reaction for hydrolyzing and condensing a silicon compound in a solvent containing water. Particles having a polysiloxane skeleton (polysiloxane particles) can be obtained by hydrolysis and condensation processes. Hydrolysis and polycondensation can employ any method such as batch, split or continuous. In the hydrolysis and condensation polymerization, basic catalysts such as ammonia, urea, ethanolamine, tetramethylammonium hydroxide, alkali metal hydroxide, and alkaline earth metal hydroxide can be preferably used as the catalyst.

  In the solvent containing water, an organic solvent can be contained in addition to water and the catalyst. Examples of the organic solvent include alcohols such as methanol, ethanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, pentanol, ethylene glycol, propylene glycol, 1,4-butanediol; acetone, Examples thereof include ketones such as methyl ethyl ketone; esters such as ethyl acetate; (cyclo) paraffins such as isooctane and cyclohexane; aromatic hydrocarbons such as benzene and toluene. These may be used alone or in combination of two or more.

  In the hydrolysis and condensation processes, anionic, cationic and nonionic surfactants and polymer dispersants such as polyvinyl alcohol and polyvinylpyrrolidone can be used in combination. These may be used alone or in combination of two or more.

  In the hydrolysis and condensation, the silicon compound as a raw material is mixed with a solvent containing a catalyst, water and an organic solvent, and then the temperature is 0 ° C. or higher and 100 ° C. or lower, preferably 0 ° C. or higher and 70 ° C. or lower, and 30 minutes or longer and 100 ° C. It can carry out by stirring for less than an hour. Further, after producing particles by performing hydrolysis and condensation reactions to a desired degree, the seed particles may be grown by using this as seed particles and further adding a silicon compound to the reaction system.

  The absorption step is not particularly limited as long as it proceeds in a state where a polymerizable monomer is present in the presence of polysiloxane particles. Therefore, the polymerizable monomer may be added to the solvent in which the polysiloxane particles are dispersed, or the polysiloxane particles may be added to the solvent containing the polymerizable monomer. In particular, as in the former case, it is preferable to add a polymerizable monomer in a solvent in which polysiloxane particles are dispersed in advance. Furthermore, the polysiloxane particles obtained in the hydrolysis and condensation steps are reacted with a reaction solution ( A method of adding a polymerizable monomer to the reaction solution without removing it from the polysiloxane particle dispersion) is preferable because the process is not complicated and the productivity is excellent.

  In the absorption step, the polymerizable monomer is absorbed in the structure of the polysiloxane particle, but the polysiloxane particle and the polymerizable monomer are so absorbed that the polymerizable monomer proceeds rapidly. Set each concentration, mixing ratio of polysiloxane and polymerizable monomer, mixing treatment method and means, temperature and time during mixing, treatment method and means after mixing, etc. under the conditions It is preferred to do so.

  The necessity of these conditions may be appropriately considered depending on the type of polysiloxane particles and polymerizable monomers used. These conditions may be applied singly or in combination of two or more.

  The addition amount of the polymerizable monomer in the absorption step is preferably 0.01 to 100 times by mass with respect to the mass of the silicon compound used as the raw material for the polysiloxane particles. More preferably, they are 0.5 times or more and 30 times or less, More preferably, they are 1 time or more and 20 times or less. When the addition amount is less than the above range, the amount of the polymerizable monomer of the polysiloxane particles absorbed is decreased, and it may be difficult to obtain the mechanical characteristics of the organic-inorganic composite particles to be generated, which exceeds the above range. In such a case, it is difficult to completely absorb the added polymerizable monomer into the polysiloxane particles, and unabsorbed polymerizable monomers remain, so that aggregation between particles may occur in the subsequent polymerization stage. May occur easily.

  In the absorption step, the timing of addition of the polymerizable monomer is not particularly limited, and the polymerizable monomer may be added all at once, may be added in several times, or any You may feed at a speed. In addition, when adding the polymerizable monomer, it may be added only with the polymerizable monomer, or a solution of the polymerizable monomer may be added. It is preferable to mix the emulsified liquid emulsified and dispersed in an aqueous medium with the polysiloxane particles because the polysiloxane particles can be more efficiently absorbed.

  Although the said emulsifier is not specifically limited, What was illustrated as surfactant which comprises the said coating composition is mentioned, for example. Among these, anionic surfactants and nonionic surfactants are preferable because they can stabilize the dispersion state of polysiloxane particles, polysiloxane particles that have absorbed a polymerizable monomer, and polymer particles. These emulsifiers may be used alone or in combination of two or more.

  The amount of the emulsifier used is not particularly limited. Specifically, the amount is preferably 0.01 parts by mass or more, more preferably 0 with respect to 100 parts by mass of the total mass of the polymerizable monomers. 0.05 parts by mass or more, more preferably 1 part by mass or more, preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and further preferably 5 parts by mass or less. When the amount of the emulsifier used is less than 0.01 parts by mass, an emulsion dispersion of a stable polymerizable monomer may not be obtained. When the amount exceeds 10 parts by mass, emulsion polymerization or the like is a side reaction. May occur together. About the said emulsification dispersion | distribution, it is preferable to usually make the said polymerizable monomer into an emulsion state in water using a homomixer, an ultrasonic homogenizer, etc. with an emulsifier.

  Moreover, when emulsifying and dispersing the polymerizable monomer with an emulsifier, it is preferable to use water or a water-soluble organic solvent that is 0.3 to 10 times the mass of the polymerizable monomer. Examples of the water-soluble organic solvent include alcohols such as methanol, ethanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, pentanol, ethylene glycol, propylene glycol, 1,4-butanediol; acetone And ketones such as methyl ethyl ketone; and esters such as ethyl acetate.

  The absorption step is preferably performed in the temperature range of 0 ° C. to 60 ° C. with stirring for 5 minutes to 720 minutes. These conditions may be set as appropriate according to the type of polysiloxane particles and polymerizable monomers used, and these conditions may be used alone or in combination of two or more.

  In the absorption step, for determining whether the monomer component is absorbed by the polysiloxane particles, for example, before adding the monomer component and after completion of the absorption step, the particles are observed with a microscope. It can be easily determined by confirming that the particle size is increased by absorption.

  The polymerization step is a step of obtaining particles having an organic polymer skeleton by polymerizing a polymerizable reactive group. Specifically, when a silicon compound having a polymerizable reactive group-containing organic group is used, it is a step of polymerizing a polymerizable reactive group of the organic group to form an organic polymer skeleton, and an absorption step. In the process of forming an organic polymer skeleton by polymerizing the polymerizable monomer having an absorbed polymerizable reactive group or the absorbed polymerizable monomer and the polymerizable reactive group of the polysiloxane skeleton. However, if both are applicable, the organic polymer skeleton can be formed by either reaction.

  The polymerization reaction may be performed in the middle of the hydrolysis-condensation step or the absorption step, and may be performed after either or both of the steps, and is not particularly limited, but usually after the hydrolysis-condensation step (the absorption step). If so, start after the absorption step).

  The polymerization reaction is not particularly limited. For example, any of a method using a radical polymerization initiator, a method of irradiating ultraviolet rays or radiation, a method of applying heat, and the like can be adopted. Although it does not specifically limit as said radical polymerization initiator, For example, what is used for superposition | polymerization of the said organic polymer particle can be mentioned. These radical polymerization initiators may be used alone or in combination of two or more.

  The amount of the radical polymerization initiator used is preferably 0.001 part by mass or more, more preferably 0.01 part by mass or more, further preferably 100 parts by mass with respect to the total mass of the polymerizable monomer. Is 0.1 parts by mass or more, preferably 20 parts by mass or less, more preferably 10 parts by mass or less, and still more preferably 5 parts by mass or less. When the usage-amount of the said radical polymerization initiator is less than 0.001 mass part, the polymerization degree of a polymerizable monomer may not rise. The method for charging the radical polymerization initiator into the solvent is not particularly limited, and is a method in which the entire amount is charged first (before the reaction is started) (an embodiment in which the radical polymerization initiator is emulsified and dispersed together with the polymerizable monomer, polymerizable A mode in which a radical polymerization initiator is charged after the monomer has been absorbed); a method in which a part is charged first, and the rest is continuously fed, or intermittently pulsed, or a combination thereof Any conventionally known method such as a method can be employed.

  The reaction temperature for the radical polymerization is preferably 40 ° C. or higher, more preferably 50 ° C. or higher, preferably 100 ° C. or lower, more preferably 80 ° C. or lower. If the reaction temperature is too low, the degree of polymerization does not increase sufficiently and the mechanical properties of the composite particles tend to be difficult to obtain. On the other hand, if the reaction temperature is too high, aggregation between particles occurs during the polymerization. It tends to happen easily. The reaction time for the radical polymerization may be appropriately changed according to the type of polymerization initiator to be used, but is usually preferably 5 minutes or more, more preferably 10 minutes or more, and preferably 600 minutes, Preferably it is 300 minutes or less. When the reaction time is too short, the degree of polymerization may not be sufficiently increased, and when the reaction time is too long, aggregation tends to occur between particles.

When a surfactant is used as a dispersion stabilizer or emulsifier when polymerizing the organic polymer particles or organic-inorganic composite particles, the surfactant remains in the resulting particles. Thus, when using organic particles containing a surfactant as the organic particles constituting the coating composition of the present invention, the surfactant content of the organic particles is preferably 550 ppm or more, more preferably It is 650 ppm or more, More preferably, it is 1000 ppm or more, It is preferable that it is 2000 ppm or less, More preferably, it is 1800 ppm or less, More preferably, it is 1600 ppm or less. When the surfactant content of the organic particles exceeds the above range, it is preferable to adjust the surfactant content by washing the organic particles by the method described later.

  In the present invention, the surfactant content of the organic particles means that the organic particles are dispersed in ion-exchanged water using ultrasonic irradiation or the like, and then the organic particle dispersion is filtered and the obtained filtrate is subjected to an interface. This is a value calculated from the measured value of the ion content by measuring the ion content derived from the activator. The ion content can be measured by using an ion chromatograph (for example, ICS-3000, manufactured by Nihon Dynax). As an analytical column used for the analysis, if the ion content to be detected is a cation, IonPac CS14 (manufactured by Nippon Dynex), if it is an anion, IonPac AS18 (manufactured by Nippon Dynax), IonPac AS4A-SC (manufactured by Nippon Dynax) Etc.) and the eluent, sample introduction amount, etc. may be appropriately selected.

  The washing method for the organic polymer particles and the organic / inorganic composite particles is not particularly limited. For example, the reaction liquid after polymerization is cooled and then filtered to obtain a solid concentration of 45% by mass to 75% by mass. A cake-like or slurry-like recovered product is obtained. A method in which a solvent is added to the obtained recovered product to adjust the solid content concentration to 20% by mass to 60% by mass, and after stirring for 30 minutes to 3 hours, the particles are filtered again by filtration. A method of cooling the reaction liquid after polymerization, adding a solvent to adjust the solid content concentration to 5% by mass to 25% by mass and then filtering to collect particles. In addition, you may perform centrifugation as a method of taking out particle | grains. Moreover, as a solvent used for washing, water and a water / alcohol mixed solution are preferable, and water is particularly preferable.

  The shape of the organic particles used in the present invention is not particularly limited, and may be any of a spherical shape, a spheroid shape, a confetti shape, a thin plate shape, a needle shape, and an eyebrows shape. In addition, for example, in the case of a spherical shape, the average particle diameter is preferably 1 μm or more, more preferably 2 μm or more, further preferably 3 μm or more, preferably 50 μm or less, more preferably 40 μm or less, Preferably it is 30 micrometers or less. When the average particle diameter of the organic particles is 1 μm or more, good light diffusibility is obtained when applied to an optical film. Moreover, sedimentation of the organic particles in the coating composition can be prevented by setting the average particle diameter of the organic particles to 50 μm or less. Here, the “average particle diameter” in the present embodiment refers to a volume average particle diameter, and is a precision particle size distribution measuring apparatus using the Coulter principle (for example, trade name “Coulter Multisizer Type III”, Beckman Coulter Co., Ltd.) The value measured by the company).

  In addition, the coefficient of variation in the particle size of the organic particles used in the present invention is expressed by the following formula: the average particle size of organic particles measured by a precision particle size distribution measuring apparatus using the Coulter principle, and the standard deviation of the particle size of organic particles. This is a value obtained by applying to.

Coefficient of variation of organic particles (%) = 100 × standard deviation of particle diameter / average particle diameter

  The organic particle content in the coating composition of the present invention is preferably 0.5% by mass or more, more preferably 1% by mass or more, still more preferably 2% by mass or more, and 35% by mass or less. More preferably, it is 30 mass% or less, More preferably, it is 25 mass% or less. When the organic particle content in the coating composition is 0.5% by mass or more, when applied to an optical film, an appropriate light scattering property is obtained, and the organic particle content is 35% by mass or less. Thus, when applied to an optical film, it is prevented that the organic particles are present at a high density and the light transmittance is not lowered.

Binder resin The coating composition of the present invention preferably contains a binder resin in addition to the organic particles and the surfactant described above. The binder resin is not particularly limited, and any binder resin can be used according to required properties such as transparency, resin fine particle dispersibility, light resistance, moisture resistance and heat resistance.

  Examples of the binder resin include (meth) acrylic resins; (meth) acrylic urethane resins; urethane resins; polyvinyl chloride resins; polyvinylidene chloride resins; melamine resins; styrene resins; alkyd resins. Phenol resin; epoxy resin; polyester resin; (meth) acryl silicone resin, alkylpolysiloxane resin, silicone resin, silicone alkyd resin, silicone urethane resin, silicone polyester resin, silicone acrylic resin, etc. Modified silicone resins; fluorinated resins such as polyvinylidene fluoride and fluoroolefin vinyl ether polymers. These binder resins may be curable resins such as thermosetting resins, ionizing radiation curable resins, thermoplastic resins, warm air curable resins, ultraviolet curable resins, and electron beam curable resins.

  In addition to the above, organic binder resins such as synthetic rubber and natural rubber, inorganic binders, and the like can be used as the binder resin. Examples of the organic binder resin include ethylene-propylene copolymer rubber, polybutadiene rubber, styrene-butadiene rubber, and acrylonitrile-butadiene rubber. Examples of the inorganic binder binder resin include silica sol, alkali silicate, silicon alkoxide, and their (hydrolyzed) condensates and phosphates. These may be used alone or in combination of two or more. Particularly preferred binder resins are (meth) acrylic resins.

  Specific examples of the (meth) acrylic resin include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) acrylate n- Butyl, isobutyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, methyl cyclohexyl (meth) acrylate, cyclododecyl (meth) acrylate, (meth) acrylic acid t A (meth) acrylic polymer containing structural units derived from butylcyclohexyl, lauryl (meth) acrylate, isobornyl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, etc. is there. Among these, a (meth) acrylic polymer containing a structural unit derived from methyl acrylate, n-butyl acrylate, isobutyl acrylate, or cyclohexyl acrylate is preferable.

  Specific examples of the ionizing radiation curable resin include those having an acrylate functional group, for example, a relatively low molecular weight polyester resin, polyether resin, acrylic resin, epoxy resin, urethane resin, alkyd resin, spiroacetal resin. , Polybutadiene resin, polythiol polyene resin and the like modified with acrylic; (meth) acrylate oligomer or prepolymer of polyfunctional compound such as polyhydric alcohol; reactive diluent and the like. Specific examples of the reactive diluent include monofunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, and N-vinylpyrrolidone; polymethylolpropane tri (meth) acrylate, hexanediol ( (Meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (meth) acrylate, neo A polyfunctional monomer such as pentyl glycol di (meth) acrylate may be mentioned.

  From the viewpoint of improving the durability of the coating film, the binder resin is preferably a curable resin capable of forming a crosslinked structure by a crosslinking reaction. The binder resin can be cured under various curing conditions. As a curing type, a room temperature curing type, a heat curing type, an ultraviolet ray or an electron beam curing type, or the like can be adopted.

Crosslinking agent component Moreover, the coating composition of this invention may contain crosslinking agent components, such as a hardening | curing agent, a crosslinking agent, and a curing catalyst. By containing a crosslinking agent component in the coating composition, the polymer in the binder resin can be crosslinked by the crosslinking agent component. The amount of the crosslinking agent component used, addition method, dispersion method and the like are not particularly limited.

  When a thermosetting resin is used as the binder resin in the coating composition of the present invention and a crosslinker component is further contained, the binder resin and the crosslinker component may have a plurality of hydroxyl groups in one molecule as the binder resin. It is preferable to contain a polyfunctional isocyanate as the polymer having the cross-linking agent component.

  The weight average molecular weight of the polymer having a plurality of hydroxyl groups in one molecule used for the binder resin is, for example, preferably 1,000 or more, more preferably 2,000 or more, and further preferably 4,000 or more. It is preferable that it is 100,000 or less, More preferably, it is 80,000 or less, More preferably, it is 60,000 or less. The weight average molecular weight is a value measured by polystyrene standard gel permeation chromatography (GPC).

  Further, the content of the monomer having a plurality of hydroxyl groups in one molecule in the polymer having a plurality of hydroxyl groups in one molecule used for the binder resin is preferably 5% by mass or more, more preferably 8% by mass. % Or more, more preferably 10% by mass or more, preferably 40% by mass or less, more preferably 30% by mass or less, and still more preferably 25% by mass or less.

  The hydroxyl value of the polymer having a plurality of hydroxyl groups in one molecule used for the binder resin is preferably 10 mgKOH / g or more, more preferably 20 mgKOH / g or more, and preferably 400 mgKOH / g or less, more preferably 200 mgKOH / g or less. The hydroxyl value of the binder resin containing a polymer having a plurality of hydroxyl groups in one molecule used for the binder resin is preferably 10 mgKOH / g or more, more preferably 20 mgKOH / g or more, and 400 mgKOH / g. The following is preferable, and more preferably 200 mgKOH / g or less. The hydroxyl value of the polymer having a plurality of hydroxyl groups in one molecule and the binder resin can be measured by, for example, an acetylation method according to JIS K1557-1.

  Examples of the polymer having a plurality of hydroxyl groups in one molecule used for the binder resin include (meth) acrylic polymers; urethane polymers; vinyl chloride polymers; vinylidene chloride polymers; styrene heavy polymers. Examples of the polymer include a phenolic polymer, an epoxy polymer, and an ester polymer. Among these, it is preferable to use a (meth) acrylic polymer as a polymer having a plurality of hydroxyl groups in one molecule in the binder resin.

  The (meth) acrylic polymer having a plurality of hydroxyl groups in one molecule used for the binder resin is preferably obtained by polymerizing a monomer composition containing a monomer component having a hydroxyl group. Examples of the monomer component having a hydroxyl group include hydroxyalkyl acrylates such as 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxybutyl acrylate; 2-hydroxyethyl methacrylate, methacrylic acid 2 -Hydroxypropyl, hydroxyalkyl methacrylate such as 2-hydroxybutyl methacrylate; hydroxyl-containing vinyl ethers such as 2-hydroxyethyl vinyl ether and 4-hydroxybutyl vinyl ether; 2-hydroxyethyl allyl ether, 4-hydroxybutyl allyl ether, etc. Hydroxyl-containing allyl ethers; parahydroxystyrene; caprolactone-modified hydroxy (meth) acrylate (for example, product name “Placcel (registered trademark) FM” manufactured by Daicel Chemical Industries, Ltd.) And the like. These hydroxyl group-containing monomer components may be used alone or in combination of two or more. Of these, hydroxyalkyl methacrylate such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, and the like are preferably used, such as 2-hydroxyethyl methacrylate, 2-hydroxybutyl methacrylate, and the like. More preferably used.

  Moreover, the (meth) acrylic-type polymer which has several hydroxyl groups in 1 molecule used for binder resin may be copolymerized with the monomer which has functional groups other than a hydroxyl group. For example, as a copolymerizable monomer, unsaturated monomer having a carboxyl group such as (meth) acrylic acid, itaconic acid, maleic anhydride; acidic phosphorus such as 2- (meth) acryloyloxyethyl acid phosphate Acid ester unsaturated monomers; unsaturated monomers having an epoxy group such as glycidyl (meth) acrylate; (meth) acrylamide, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl ( Unsaturated monomers having nitrogen atoms such as meth) acrylate and imide (meth) acrylate; ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane Tri (meth) acrylate, pentaerythritol Unsaturated monomer having two or more polymerizable double bonds such as tho (meth) acrylate; Unsaturated monomer having halogen atom such as vinyl chloride; Aromatic unsaturation such as styrene and α-methylstyrene Monomers; vinyl esters such as vinyl acetate; vinyl ethers and the like. These may be used alone or in combination of two or more.

  As a polymerization method for producing a (meth) acrylic polymer having a plurality of hydroxyl groups in one molecule used for a binder resin, conventionally known polymerization methods such as solution polymerization, dispersion polymerization, suspension polymerization, emulsion polymerization, etc. Can be adopted. These polymerization methods can be performed using a polymerization initiator. The solvent for performing the solution polymerization is not particularly limited. For example, an aromatic solvent such as toluene or xylene; an alcohol solvent such as isopropyl alcohol, n-butyl alcohol, propylene glycol methyl ether, or dipropylene glycol methyl ether; One or more solvents selected from the group consisting of ester solvents such as butyl acetate, ethyl acetate and cellosolve acetate; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone, and dimethylformamide can be used. What is necessary is just to set the usage-amount of a solvent suitably with polymerization conditions, the mass ratio of a polymer, etc.

  The said polymerization initiator is not specifically limited, A general radical polymerization initiator can be used. Although it does not specifically limit as said radical polymerization initiator, For example, what is used for superposition | polymerization of the said organic polymer particle can be mentioned. These radical polymerization initiators may be used alone or in combination of two or more. What is necessary is just to set the usage-amount of these polymerization initiators suitably from the characteristic value etc. of a desired polymer. A preferred use ratio of the polymerization initiator is, for example, preferably 0.01% by mass or more and 50% by mass or less, and more preferably 0.05% by mass or more and 20% by mass or less with respect to the whole monomer.

  The polymerization conditions in the polymerization method may be appropriately set depending on the polymerization method, and are not particularly limited. For example, the polymerization temperature is preferably from room temperature to 200 ° C., more preferably from 40 ° C. to 140 ° C. The polymerization reaction time may be appropriately set so that the polymerization reaction is completed according to the composition of the monomer component, the type of the polymerization initiator, and the like.

  The weight average molecular weight of the (meth) acrylic polymer having a plurality of hydroxyl groups in one molecule used as the binder resin is, for example, preferably 1,000 or more, more preferably 2,000 or more, Preferably it is 4,000 or more, it is preferable that it is 100,000 or less, More preferably, it is 80,000 or less, More preferably, it is 60,000 or less. The weight average molecular weight is a value measured by polystyrene standard gel permeation chromatography (GPC).

  As polyfunctional isocyanate used as a crosslinking agent component, the blocked polyisocyanate compound which blocked the isocyanate group of the polyisocyanate compound and / or the said polyisocyanate compound with the blocking agent is mentioned, for example.

  The polyisocyanate compound is not particularly limited as long as it is a compound having at least two isocyanate groups in one molecule. For example, tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, 1,6-hexamethylene diisocyanate, isophorone diisocyanate. , 4,4'-methylenebis (cyclohexyl isocyanate), lysine diisocyanate, trimethylhexamethylene diisocyanate, 1,3- (isocyanatomethyl) cyclohexane, 1,5-naphthalene diisocyanate, triphenylmethane triisocyanate, and the like; Polyisocyanate derivatives (modified products) such as polyisocyanate adducts, burettes, and isocyanurates It is.

  The blocked polyisocyanate compound is usually a compound obtained by blocking an isocyanate group of a polyisocyanate compound with a blocking agent. With this blocked polyisocyanate compound, the binder resin can be cross-linked during heating and drying, and the storage stability at room temperature is enhanced. The blocking agent is not particularly limited, and examples thereof include compounds such as ε-caprolactam, phenol, cresol, oxime, and alcohol. These blocked polyisocyanate compounds may be used alone or in combination of two or more.

  As a commercial item of the said polyisocyanate compound or blocked polyisocyanate compound, for example, “Sumijour (registered trademark) N3300, BL3175”, “Desmodule (registered trademark) N3200, N3400, N3600, manufactured by Sumika Bayer Urethane Co., Ltd., VPLS 2102 ”,“ Coronate (registered trademark) HK, HL, HX ”manufactured by Nippon Polyurethane Industry Co., Ltd.,“ Duranate (registered trademark) E-402-90T ”manufactured by Asahi Kasei Kogyo Co., Ltd. and the like. From the viewpoint of preventing yellowing of the binder resin, a non-yellowing polyisocyanate compound having no isocyanate group directly bonded to the aromatic ring is preferable.

  The amount of the polyfunctional isocyanate used is not particularly limited. For example, the polyfunctional isocyanate has 1 mol of hydroxyl groups in a binder resin (preferably a binder resin made of a polymer having a plurality of hydroxyl groups in one molecule). It is desirable that the isocyanate group be 0.6 mol or more and 2 mol or less, more preferably 0.8 mol or more and 1.5 mol or less. When the isocyanate group of the polyfunctional isocyanate is less than 0.6 moles per mole of hydroxyl groups in the binder resin, many unreacted hydroxyl groups remain in the matrix component after curing, so the weather resistance of the resulting coating film May decrease. On the other hand, when the number of isocyanate groups of the polyfunctional isocyanate exceeds 1.5 moles relative to 1 mole of hydroxyl groups in the binder resin, many unreacted isocyanate groups remain in the matrix component, which reacts with moisture in the air. Thus, foaming or whitening may occur in the coating film.

  The glass transition temperature (Tg) of the binder resin is preferably −80 ° C. or higher, more preferably −50 ° C. or higher, still more preferably 0 ° C. or higher, and most preferably 20 ° C. or higher, and 160 ° C. or lower. More preferably, it is 130 degrees C or less, More preferably, it is 110 degrees C or less, Most preferably, it is 100 degrees C or less. If the glass transition temperature of binder resin is said range, the light resistance of binder resin will improve.

Photopolymerization initiator When an ultraviolet curable resin is used as the binder resin, it is preferable to add a photopolymerization initiator to the coating composition.

  The photopolymerization initiator is not particularly limited, and examples thereof include acetophenones, benzophenones, Michler benzoylbenzoate, α-amyloxime ester, tetramethylchuram monosulfide, and thioxanthones. Specific examples of the photopolymerization initiator include “Irgacure (registered trademark) 184” commercially available from Ciba Japan.

  The addition amount of the photopolymerization initiator is preferably 0.1 parts by mass or more, more preferably 3 parts by mass or more, and preferably 10 parts by mass or less, with respect to 100 parts by mass of the polyfunctional monomer in the binder resin. More preferably, it is 7 parts by mass or less.

  In addition, when adding a photoinitiator to a coating composition, it is preferable to use a photosensitizer together. Examples of the photosensitizer include n-butylamine, triethylamine, and poly-n-butylphosphine.

Solvent The coating composition of the present invention preferably contains a solvent. By containing the solvent, the coating on the substrate becomes easy. Examples of the solvent include aromatic solvents such as toluene and xylene; alcohol solvents such as isopropyl alcohol, n-butyl alcohol, propylene glycol methyl ether, and dipropylene glycol methyl ether; ester systems such as butyl acetate, ethyl acetate, and cellosolve acetate. Solvents: ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and dimethylformamide. These solvents may be used alone or in combination of two or more.

Leveling agent The coating composition of the present invention preferably contains a leveling agent. By containing a leveling agent, when applying a coating composition to an optical film, it effectively prevents inhibition of curing by oxygen on the surface of the coating film when applied to the base film or during drying, and is resistant to resistance. Abrasion property can be improved. Examples of the leveling agent include fluorine-based and silicone-based ones. Specific examples of the leveling agent include “BYK320” commercially available from Big Chemie.

  In addition, the coating composition of the present invention may contain other components as necessary as long as the effects of the present invention are not impaired. Examples of other components include pigments, dyes, plasticizers, polymerization stabilizers, antioxidants, fluorescent brighteners, ultraviolet absorbers, and antistatic agents. These may use only 1 type and may use 2 or more types together.

  In particular, when the coating composition of the present invention is used for an antiglare layer film or the like, an inorganic filler may be added to increase the refractive index of the antiglare layer formed from the coating composition of the present invention. When the inorganic filler is added, the amount of the inorganic filler added is preferably 10% by mass or more, more preferably 20% by mass or more, and further preferably 30% by mass or more of the total solid content of the coating composition. 90% by mass or less, more preferably 80% by mass or less, and still more preferably 75% by mass or less.

  The inorganic filler is preferably made of an oxide of at least one metal selected from the group consisting of titanium, zirconium, aluminum, indium, zinc, tin and antimony.

  The average particle size of the inorganic filler is preferably 0.2 μm or less, more preferably 0.1 μm or less, and still more preferably 0.06 μm or less. Inorganic fillers having such an average particle size do not scatter because the particle size is sufficiently smaller than the wavelength of light, and the dispersion in which the inorganic filler is dispersed in the binder resin acts as an optically uniform substance. To do. In addition, the average particle diameter of an inorganic filler shall point out a volume average particle diameter, and shall be a value measured with the particle size distribution measuring apparatus using a dynamic light scattering principle.

Manufacturing method of coating composition The coating composition of the present invention is obtained by mixing the surfactant and organic particles described above with a binder resin, a crosslinking agent component, a photopolymerization initiator, a solvent, a leveling agent, and the like as necessary. Can be produced. In addition, as a manufacturing method of the coating composition of this invention, the aspect using the organic particle by which surfactant content was adjusted to 550 ppm-2000 ppm is preferable.

Use When the coating composition of the present invention contains a binder resin, the resulting coating film is a molded body in which organic particles are dispersed and fixed in the binder resin, so that it has excellent light diffusibility and light transmittance. It has optical characteristics. Therefore, the coating composition containing the binder resin is suitably used for forming a light diffusion layer of a light diffusion film that uniformly diffuses light from a light source on an image display surface in an image display device.

  Further, the coating composition containing the binder resin forms an antiglare layer of an antiglare film that diffuses surface reflected light and prevents reflection of external light in order to improve the visibility of the image display device surface. Is preferably used.

Light Diffusion Film The light diffusion film of the present invention has a base film and a light diffusion layer formed from the coating composition of the present invention on at least one surface of the base film. .

  Here, the specific structural example of the light-diffusion film of this invention is shown in FIG. As shown in FIG. 1, the light-diffusion film 1 has the base film 2 and the light-diffusion layer A obtained from the coating composition of this invention on the surface of the base film 2. As shown in FIG. The light diffusing layer A includes organic particles 4 and a matrix component 3 that is a cured product such as a binder resin in which the organic particles 4 are dispersed.

  In the light diffusing film 1 of the present invention, a material that can be generally used as an optical material is preferably used for the base film 2. Examples of the material of the base film 2 include glass; polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); triacetyl cellulose; olefin resins such as cyclopolyolefin and amorphous polyolefin; polymethyl methacrylate; Examples include (meth) acrylic resins such as (meth) acrylates having a lactone ring; polystyrene; polycarbonates; polyvinyl acetals such as butyral resins; and polyaryl ether resins. As the material of the base film 2, a PET film excellent in surface smoothness and mechanical strength and a (meth) acrylic resin film having a lactone ring structure are particularly preferably used.

  The thickness of the base film 2 is preferably 10 μm or more from the viewpoint of suppressing the warp caused by heat shrinkage and improving the handleability and strength. Moreover, from the viewpoint of increasing the visible light transmittance and improving the front luminance of the backlight unit, the thickness of the base film 2 is preferably 300 μm or less.

  The light diffusion layer A is formed by applying and drying the coating composition of the present invention, and performing a crosslinking treatment as necessary, and has a function of sufficiently diffusing incident light. The thickness of the light diffusion layer A is preferably 1 μm or more, more preferably 10 μm or more, preferably 100 μm or less, and more preferably 30 μm or less. When the thickness of the light diffusion layer A is less than 1 μm, the light incident on the light diffusion layer may not be sufficiently diffused. On the other hand, when the thickness of the light diffusion layer exceeds 100 μm, the amount of light passing through the light diffusion layer decreases, and the total light transmittance and luminance may decrease. The light diffusing layer A may be formed of a single layer or two or more layers, and may be formed of one type of the same single layer or two or more types of different layers. You may be comprised from.

  Here, as for the thickness of the light diffusion layer A, the thickness of the light diffusion layer A was measured at at least five locations arbitrarily selected in the light diffusion film 1, and the average value thereof was taken as the thickness of the light diffusion layer A. Specifically, a part of the light diffusing film 1 is embedded and solidified with an epoxy resin, then cut into a thin piece in the cross-sectional direction of the light diffusing film 1 with a microtome, and this is observed with a transmission electron microscope as a sample To do. The thickness of the light diffusion layer A in the electron microscope image was measured, and the average value measured at least at five locations was taken as the thickness of the light diffusion layer A.

  And as for the light-diffusion layer A formed on the base film 2, the unevenness | corrugation may be formed in the surface, and there may be no unevenness | corrugation on the surface and it may become flat. In addition, in order to obtain the light-diffusion film 1 with higher luminance, it is preferable that the surface of the light diffusion layer A has irregularities. In this case, it is preferable that at least a part of the convex portions formed on the surface of the light diffusion layer A is based on the presence of the organic particles 4. The number of protrusions based on the presence of the organic particles 4 in the protrusions formed on the surface of the light diffusion layer A is preferably 50% or more, more preferably 80% or more, and particularly preferably 90%. That's it.

  As an aspect of the convex portion based on the presence of the organic particles 4, either an aspect in which at least a part of the organic particles 4 is exposed from the matrix component 3 or an aspect in which the organic particles 4 are covered with the matrix component 3 is used. There may be a mixture of these aspects. In addition, it is preferable that all the convex parts based on the presence of the organic particles 4 are in a form in which the organic particles 4 are covered with the matrix component 3.

  Further, the three-dimensional average roughness of the surface of the light diffusion layer A is preferably 1 μm or more, more preferably 1.5 μm or more, further preferably 2 μm or more, preferably 10 μm or less, more preferably 5 μm or less, still more preferably Is 4 μm or less. If the three-dimensional average roughness of the surface of the light diffusion layer A is less than 1 μm, the desired light diffusibility may not be obtained. If the surface roughness exceeds 10 μm, the light diffusibility of the light diffusion layer A becomes too strong. The brightness of the light diffusing film may be reduced.

  The light diffusion film preferably has a haze of 75% or more, more preferably 80% or more, still more preferably 85% or more, and 95% or less, more preferably 90% or less. The total light transmittance of the light diffusion film is preferably as high as possible, preferably 60% or more, more preferably 65% or more, and still more preferably 70% or more. Haze and total light transmittance can be measured by a measuring method based on JIS K7105 using a turbidimeter (for example, NDH-1001DP, manufactured by Nippon Denshoku Industries Co., Ltd.).

Antiglare Film The antiglare film of the present invention is characterized by having a base film and an antiglare layer formed from the coating composition of the present invention on at least one surface of the base film. .

  The base film for the antiglare film can be used without particular limitation as long as it does not impair transparency. Examples of film base materials used for such antiglare films include polyester polymers such as polyethylene terephthalate and polyethylene naphthalate; cellulose polymers such as diacetyl cellulose and triacetyl cellulose; polycarbonate polymers; polymethyl methacrylate and the like. Acrylic polymer; Styrene polymer such as styrene and acrylonitrile / styrene copolymer; Olefin polymer such as polyethylene, polypropylene, polyolefin having cyclic or norvolene structure, ethylene / propylene copolymer; Vinyl chloride polymer; Nylon and aromatic Amide polymers such as aromatic polyamides; imide polymers; sulfone polymers; polyethersulfone polymers; polyetheretherketo System polymers; polyphenylene sulfide-based polymers; vinyl alcohol-based polymer; vinylidene chloride polymer; vinyl butyral-based polymers; arylate polymers; polyoxymethylene polymer; mixture of an epoxy-based polymer or the polymer, and the like. Among these, those having a low optical birefringence are particularly preferably used, and cellulose polymers such as diacetyl cellulose and triacetyl cellulose are preferred.

  The antiglare layer can be formed by applying and drying the coating composition of the present invention and further subjecting it to a curing treatment. Examples of the method for applying the coating composition to the base film include a roll coating method, a Miya bar coating method, and a gravure coating method.

  In addition, when applying the coating composition of the present invention to an antiglare film, it is preferable to use an ultraviolet curable resin or an electron beam curable resin as a binder resin, and employ ultraviolet curing or electron beam curing as a curing treatment. .

  Examples of the ultraviolet light source used for ultraviolet curing include an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a black light fluorescent lamp, and a metal halide lamp. As the wavelength of the ultraviolet light, a wavelength range of 190 nm to 380 nm can be used. Examples of electron beam sources used for electron beam curing include various types of electron beam accelerators such as cockcroft-wald type, pandegraft type, resonant transformer type, insulated core transformer type, linear type, dynamitron type, and high frequency type. .

  The refractive index of the antiglare layer is preferably 1.48 or more, more preferably 1.50 or more, further preferably 1.52 or more, preferably 1.70 or less, more preferably 1.65 or less, and further Preferably it is 1.62 or less. In addition, the refractive index of an anti-glare layer can be adjusted by selecting suitably the kind, mass ratio, etc. of binder resin and an inorganic filler.

  The thickness of the antiglare layer is preferably 0.5 μm or more, more preferably 1 μm or more, further preferably 2 μm or more, preferably 10 μm or less, and more preferably 7 μm or less. In addition, what is necessary is just to measure the thickness of an anti-glare layer similarly to the said light-diffusion layer.

  Hereinafter, the present invention will be described in detail based on examples. However, the following examples are not intended to limit the present invention, and all modifications made without departing from the spirit of the preceding and following descriptions are included in the technical scope of the present invention. Various measurements and evaluation methods were performed as follows.

[Average particle size]
Using an accurate particle size distribution analyzer (trade name “Coulter Multisizer III”, manufactured by Beckman Coulter, Inc.), the average particle size of the organic particles was measured under the condition of an aperture of 50 μm, and the coefficient of variation was calculated.

[Surfactant concentration]
After putting 0.2 g of organic particles prepared in Examples or Comparative Examples and 10 g of ion-exchanged water into a washed plastic container, the organic particles were sufficiently dispersed by irradiating ultrasonic waves for 10 minutes. This organic particle dispersion was filtered with a membrane filter (PTFE (polytetrafluoroethylene) membrane filter manufactured by Advantech Toyo Co., Ltd., product name “H100A090C”), and the filtrate was received in a 10 ml capacity plastic container. The obtained filtrate was analyzed using an ion chromatograph under the following conditions to measure the ion content derived from the surfactant. The product obtained by multiplying the measured value of the ion content by the dilution rate (50 times) of the organic particles was used as the surfactant content of the organic particles.
Measuring condition apparatus: Nippon Dionex, ICP-3000,
Column: IonPac CG14 (guard column, dimensions: 4 mm ID × 50 mm, manufactured by Nippon Dionex) and IonPac CS14 (analytical column, dimensions: 4 mm ID × 250 mm, manufactured by Nippon Dionex) were used.
Eluent: methanesulfonic acid 4 mmol / L,
Eluent flow rate: 1.0 ml / min,
Suppressor: Nippon Dainex Co., Ltd., CSRS-ULTRA II (external mode),
Regenerating liquid: ultrapure water,
Column temperature: 40 ° C
Sample introduction volume: 25 μl.

  In the coating compositions prepared in Examples and Comparative Examples, the surfactant contained in the organic particles is substantially brought into the coating composition as it is. The surfactant content relative to the organic particles in the composition was used.

[appearance]
The coated surface of the light diffusing film or the antiglare film prepared in Examples or Comparative Examples was visually observed to evaluate the uniformity of the coated surface.
A: The coated surface coated with the coating composition is uniform over the entire surface and has no unevenness.
○: Slight unevenness is observed on the coated surface coated with the coating composition, but it is uniform over almost the entire surface.
(Triangle | delta): The location where the coating surface coated with the coating composition is uneven and uneven is conspicuous.
X: The coating surface coated with the coating composition is non-uniform and uneven over the entire surface.

Example 1
Organic polymer particles In a flask equipped with a stirrer, inert gas introduction tube, reflux condenser and thermometer, sodium lauryl sulfate as an anionic surfactant (trade name “Emar (registered trademark) 0”, manufactured by Kao Corporation) 150 parts by mass of a solution of deionized water having 2 parts by mass dissolved therein was charged. A monomer mixture consisting of 75 parts by weight of methyl methacrylate (MMA) and 25 parts by weight of ethylene glycol dimethacrylate (EGDMA), and dimethyl 2,2-azobisisobutylate as a polymerization initiator. Charge 2 parts by mass of nitrile, K. The mixture was stirred at 4000 rpm for 5 minutes with a homogenizer (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain a uniform suspension.

  250 parts by mass of deionized water was added to the suspension, and the reaction solution was heated to 75 ° C. while blowing nitrogen gas from an inert gas introduction tube, and the polymerization reaction was continued at this temperature for 4 hours with stirring. .

  The reaction solution (suspension) was cooled and then filtered, and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. Ion exchange water was added to this recovered product to adjust the solid content concentration to 40% by mass, and the mixture was stirred for 30 minutes and then filtered to recover the washed polymerization product. At this time, the solid content concentration of the recovered product after washing was 65% by mass. After washing, the recovered product was dried at 100 ° C. for 6 hours with a dryer to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

Coating composition: Prepare a four-necked flask equipped with a stirrer, thermometer, cooler, dropping funnel and nitrogen gas inlet tube. Put 100 parts by mass of butyl acetate as a solvent in this flask and raise the temperature to the reflux temperature. did. Next, while introducing nitrogen gas from a nitrogen gas introduction tube, 40 parts by mass of methyl methacrylate as a monomer, 32.0 parts by mass of n-butyl methacrylate, 13.0 parts by mass of n-butyl acrylate, 2-hydroxyethyl 13.9 parts by weight of methacrylate and 1.1 parts by weight of methacrylic acid, and tert-butyl peroxy-2-ethylhexanoate (trade name “Perbutyl (registered trademark) O” as a polymerization initiator, manufactured by NOF Corporation) ) A binder resin monomer mixture consisting of 3.0 parts by mass was charged into a dropping funnel. This monomer mixture for binder resin was dropped from the dropping funnel over 3 hours. Furthermore, 0.6 parts by mass of tert-butylperoxy-2-ethylhexanoate was added three times by 0.2 parts by mass at intervals of 30 minutes, and kept at the reflux temperature for 2 hours. The reaction solution after completion of the reaction was cooled to room temperature, concentrated with an evaporator, and then vacuum dried to obtain a binder resin composed of a polymer having a plurality of hydroxyl groups in one molecule.

  Next, 26.8 g of the organic polymer particles and 39.0 g of butyl acetate as a solvent were mixed with a disper to obtain a coating composition. Further, 22.3 g of the binder resin and 2.19 g of an isocyanate compound (trade name “Desmodur (registered trademark) N3200”, manufactured by Sumika Bayer Urethane Co., Ltd.) as a crosslinking agent component are sufficiently added to the coating composition. Mixed. The surfactant concentration in the obtained coating composition was measured. The results are shown in Table 1.

Light Diffusion Film The coating composition obtained above was used as a bar coater No. 6 was applied to the surface of a PET film (trade name “Cosmo Shine (registered trademark) A-4300”, film thickness 100 μm, manufactured by Toyobo Co., Ltd.), dried with hot air at 100 ° C. for 2 minutes, and light diffusion layer A dried coating film was obtained. Then, in order to accelerate | stimulate hardening reaction, it age | cure | ripened at 50 degreeC for 4 hours, and obtained the light-diffusion film. Table 1 shows the appearance evaluation results of the obtained light diffusion film.

Example 2
The anionic surfactant was changed to 2 parts by mass of polyoxyethylene distyryl phenyl ether sulfate ammonium salt (trade name “Hytenol (registered trademark) LA-10”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Except that the blending was changed to 80 parts by weight of butyl methacrylate (BMA) and 20 parts by weight of ethylene glycol dimethacrylate (EGDMA), the polymerization reaction and washing were performed in the same manner as in Example 1 to produce organic polymer particles. The average particle size and the surfactant content were measured.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Example 3
An anionic surfactant was prepared by adding 1 part by mass of sodium lauryl sulfate (trade name “Emar (registered trademark) 0”, manufactured by Kao Corporation), ammonium salt of polyoxyethylene distyryl phenyl ether sulfate (trade name “HITENOL (registered trademark)” ) NF-08 ”(Daiichi Kogyo Seiyaku Co., Ltd.) 1 part by mass, the monomer mixture was changed to 70 parts by mass of butyl methacrylate (BMA) and 30 parts by mass of ethylene glycol dimethacrylate (EGDMA). Except for this, the polymerization reaction was carried out in the same manner as in Example 1.

  After cooling the reaction solution after the reaction, 500 parts by mass of ion-exchanged water was added to 100 parts by mass of the reaction solution and stirred for 30 minutes, followed by filtration to collect a polymerization product. At this time, the solid content concentration of the recovered product was 68% by mass. The recovered material was dried at 100 ° C. for 6 hours with a dryer to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Reference example 4
The anionic surfactant was changed to 0.5 parts by mass of polyoxyethylene distyryl phenyl ether sulfate ammonium salt (trade name “Hytenol (registered trademark) NF-08”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). The polymerization reaction was carried out in the same manner as in Example 1 except that the blend of the monomer mixture was changed to 90 parts by mass of styrene (St) and 10 parts by mass of trimethylolpropane trimethacrylate (TMPTMA). The reaction solution (suspension) was cooled and then filtered, and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. The recovered material was dried at 100 ° C. for 6 hours with a dryer to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Example 5
Organic-inorganic composite particles In a four-necked flask equipped with a cooling tube, a thermometer, and a dropping port, 526 parts by mass of ion-exchanged water, 1.6 parts by mass of a 25 mol% aqueous ammonia solution, and 118 parts by mass of methanol were placed and stirred. 25 parts by mass of 3-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-503) was added to the mixture from the dropping port, and hydrolysis and condensation of 3-methacryloxypropyltrimethoxysilane was performed to prepare an organopoly Siloxane particles were prepared. Two hours after the start of the reaction, the obtained emulsion of organopolysiloxane particles was sampled, and the particle size was measured with a Coulter Multisizer (manufactured by Beckman Coulter, Inc.). The average particle size was 1.8 μm.

  Subsequently, 60 masses of styrene was added to a solution in which 2.0 mass parts of polyoxyethylene styrenated phenyl ether sulfate ammonium salt (manufactured by Daiichi Kogyo Co., Ltd., Hightenol NF-08) was dissolved in 175 mass parts of ion-exchanged water as an emulsifier. Part, 1,6-hexanediol dimethacrylate 40 parts by mass, 2,2′-azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd., V-65) dissolved in 2 parts by mass The emulsion is prepared by emulsifying and dispersing at 6000 rpm for 5 minutes using a TK homomixer (manufactured by Koki Kogyo Kogyo Co., Ltd.). went. Two hours after the addition of the monomer emulsion, the reaction solution was sampled and observed with a microscope. As a result, it was confirmed that the organopolysiloxane particles absorbed the monomer and were enlarged.

  Next, the reaction solution was heated to 65 ° C. under a nitrogen atmosphere and held at 65 ° C. for 2 hours to perform radical polymerization of the monomer. The reaction solution was cooled and then filtered, and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. Ion exchanged water was added to the recovered product to a solid content concentration of 40% by mass, stirred for 30 minutes, and then filtered to recover the washed polymerization product. At this time, the solid content concentration of the recovered product after washing was 63% by mass. After washing, the recovered material was dried at 100 ° C. for 6 hours with a dryer to obtain organic-inorganic composite particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). When the average particle diameter of the obtained organic / inorganic composite particles was measured, the average particle diameter was 3.6 μm, and the coefficient of variation was 6.2%. Further, the surfactant content of the organic-inorganic composite particles was measured. The results are shown in Table 1.

Coating Composition A coating composition was prepared by mixing 1 part by mass of the organic-inorganic composite particles, 20 parts by mass of toluene as a solvent, 23 parts by mass of methyl ethyl ketone (MEK), and 2 parts by mass of ethylene glycol monobutyl ether (butyl cellosolve). Further, the coating composition includes 40 parts by mass of an acrylic ionizing radiation curable resin as a binder resin, 2 parts by mass of Irgacure (registered trademark) 907 (manufactured by Ciba Japan, photopolymerization initiator) as a polymerization initiator, and a leveling agent. As BYK320 (by Big Chemie) 0.5 part by mass was added and sufficiently stirred. The surfactant concentration in the obtained coating composition was measured. The results are shown in Table 1.

Anti-glare film The coating composition obtained above was treated with a bar coater No. 6 was applied to one surface of a triacetylcellulose film (trade name “Fujitac (registered trademark)”, film thickness 80 μm, manufactured by Fuji Photo Film Co., Ltd.), and the solvent was evaporated with a dryer at 80 ° C. An anti-glare film was obtained by irradiating ultraviolet light of 300 mJ / cm ² using a mercury lamp. Table 1 shows the appearance evaluation results of the obtained antiglare film.

Comparative Example 1
A polymerization reaction was carried out in the same manner as in Example 1 except that the anionic surfactant was changed to 1 part by mass of sodium lauryl sulfate (trade name “Emar (registered trademark) 0”, manufactured by Kao Corporation). The reaction solution (suspension) was cooled and then filtered, and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. The recovered material was dried at 100 ° C. for 6 hours with a dryer to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Comparative Example 2
The anionic surfactant was changed to 2.0 parts by mass of polyoxyethylene distyrylphenyl ether sulfate ammonium salt (trade name “Hytenol (registered trademark) LA-10”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). A polymerization reaction was carried out in the same manner as in Example 1 except that the blend of the monomer mixture was changed to 80 parts by mass of butyl methacrylate (BMA) and 20 parts by mass of ethylene glycol dimethacrylate (EGDMA).

  The reaction solution was cooled and filtered, and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. Ion exchange water was added to this recovered product to adjust the solid content concentration to 40% by mass, and the mixture was stirred for 30 minutes and then filtered to recover the washed polymerization product. At this time, the solid content concentration of the recovered product after washing was 63% by mass. Subsequently, the same operation as described above was repeated twice, and the washing operation was performed three times in total. The solid content concentrations of the second and third filtration collections were 65% by mass and 62% by mass, respectively. The recovered product after washing three times was dried with a dryer at 100 ° C. for 6 hours to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Comparative Example 3
An anionic surfactant was prepared by adding 1 part by mass of sodium lauryl sulfate (trade name “Emar (registered trademark) 0”, manufactured by Kao Corporation), ammonium salt of polyoxyethylene distyryl phenyl ether sulfate (trade name “HITENOL (registered trademark)” ) NF-08 ”(Daiichi Kogyo Seiyaku Co., Ltd.) 1 part by mass, the monomer mixture was changed to 70 parts by mass of butyl methacrylate (BMA) and 30 parts by mass of ethylene glycol dimethacrylate (EGDMA). Except for this, the polymerization reaction was carried out in the same manner as in Example 1. The reaction solution (suspension) was cooled and then filtered, and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. The recovered material was dried at 100 ° C. for 6 hours with a dryer to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Comparative Example 4
The anionic surfactant was changed to 0.5 parts by mass of polyoxyethylene distyryl phenyl ether sulfate ammonium salt (trade name “Hytenol (registered trademark) NF-08”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.). The polymerization reaction was carried out in the same manner as in Example 1 except that the blend of the monomer mixture was changed to 90 parts by mass of styrene (St) and 10 parts by mass of trimethylolpropane trimethacrylate (TMPTMA).

  After cooling the reaction solution after the reaction, 500 parts by mass of ion-exchanged water was added to 100 parts by mass of the reaction solution and stirred for 30 minutes, followed by filtration to collect a polymerization product. At this time, the solid content concentration of the recovered product was 68% by mass. The recovered material was dried at 100 ° C. for 6 hours with a dryer to obtain organic polymer particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). The obtained organic polymer particles were measured for average particle size and surfactant content. The results are shown in Table 1.

  A coating composition was prepared in the same manner as Example 1 using the obtained organic polymer particles. The surfactant concentration in the coating composition was measured. Subsequently, the light-diffusion film was produced like Example 1, and the external appearance of the obtained light-diffusion film was evaluated. The results are shown in Table 1.

Comparative Example 5
A polymerization reaction was similarly performed using the same raw materials as in Example 5. After cooling the reaction solution, it was filtered and the polymerization product was collected by filtration. At this time, the solid content concentration of the recovered product was 68% by mass. The recovered material was dried with a dryer at 100 ° C. for 6 hours to obtain organic-inorganic composite particles. In addition, all filtration was performed using quantitative filter paper (Advantech Toyo Co., Ltd. make, quantitative filter paper No. 5C). When the average particle diameter of the obtained organic / inorganic composite particles was measured, the average particle diameter was 3.6 μm, and the coefficient of variation was 6.2%. Further, the surfactant content of the organic-inorganic composite particles was measured. The results are shown in Table 1.

  A coating composition was prepared in the same manner as in Example 5 using the obtained organic-inorganic composite particles. The surfactant concentration in the coating composition was measured. Next, an antiglare film was produced in the same manner as in Example 5, and the appearance of the obtained antiglare film was evaluated. The results are shown in Table 1.

MMA: methyl methacrylate BMA: butyl methacrylate St: styrene EGDMA: ethylene glycol dimethacrylate TMPTMA: trimethylolpropane trimethacrylate KBM-503: 3-methacryloxypropyltrimethoxysilane (trade name “KBM-503”, Shin-Etsu Chemical Co., Ltd. Made)
16HX: 1,6-hexanediol dimethacrylate SDS: sodium lauryl sulfate (trade name “Emar (registered trademark) 0”, manufactured by Kao Corporation)
LA-10: Polyoxyethylene distyryl phenyl ether sulfate ammonium salt (trade name “HITENOL (registered trademark) LA-10”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)
NF-08: polyoxyethylene distyryl phenyl ether sulfate ammonium salt (trade name “Hytenol (registered trademark) NF-08”, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.)

As is clear from Table 1, the light diffusion films (Examples 1 to 3 and 5) prepared using the coating composition containing 550 ppm to 2000 ppm of the surfactant all have the coating surface of the coating composition. It was uniform overall. On the other hand, all of the light diffusion films (Comparative Examples 1 to 5) produced using the coating composition having a surfactant concentration of less than 550 ppm or more than 2000 ppm are non-uniform on the coating surface of the coating composition. Some parts were seen.

  The coating composition of this invention can be utilized suitably for the light-diffusion layer of a light-diffusion film.

It is a schematic sectional drawing which shows the structure of a light-diffusion film.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light diffusion film 2 Base film 3 Binder resin 4 Organic particle A Light diffusion layer

Claims (13)

A solvent-based coating composition containing organic particles, a surfactant, and a solvent,
The content of the surfactant is 550 ppm to 2000 ppm with respect to the organic particles,
It said solvent is at least one solvent selected from aromatic solvents, alcohol solvents, ester solvents and ketone-based Solvent O Li Cheng group,
The organic particles are vinyl polymer particles or organic-inorganic composite particles,
The organic particles have a volume average particle diameter of 1 μm or more and 8.5 μm or less as measured by a precision particle size distribution measuring apparatus using the Coulter principle, and a solvent-free coating composition containing no water.   The coating composition according to claim 1, wherein the organic particles are organic polymer particles obtained by polymerizing a monomer composition.   The coating composition according to claim 1, wherein the monomer composition includes a monomer mixture containing a vinyl monomer.   The coating composition according to claim 3, wherein the monomer mixture contains 1% by mass to 50% by mass of a crosslinkable monomer.   The coating composition according to claim 1, wherein the organic particles are organic-inorganic composite particles having an organic polymer skeleton and a polysiloxane skeleton.   The coating composition according to any one of claims 1 to 5, wherein the surfactant is an anionic surfactant.   The coating composition according to any one of claims 1 to 6, wherein the surfactant remains in the organic particles.   Furthermore, the coating composition as described in any one of Claims 1-7 containing binder resin.   Furthermore, the coating composition as described in any one of Claims 1-8 containing a crosslinking agent component.   Organic particles used in the coating composition according to any one of claims 1 to 9.   The organic particles according to claim 10 containing 550 ppm to 2000 ppm of a surfactant.   An antiglare film comprising: a base film; and an antiglare layer formed from the coating composition according to any one of claims 1 to 9 on at least one surface of the base film.   A light diffusion film comprising: a base film; and a light diffusion layer formed from the coating composition according to any one of claims 1 to 9 on at least one surface of the base film.