JP2012057177A - Organic particle for light diffusing medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide organic particles which are dispersed stably without flocculation when preparing a composition containing the organic particles by being mixed with a solvent or the like, and which form secondary particles by flocculating by interaction of the organic particles without adding an additive such as a flocculant, when the solvent is vaporized from the composition containing the organic particles.SOLUTION: In the organic particles obtained by polymerizing a monomer composition, the variation coefficient of the particle size is ≤20%, and the hydrophobic index is 35-65.

Description

  The present invention relates to organic particles and an organic particle-containing composition using the same.

  Organic particles mainly composed of resin are anti-blocking agents for resin films, additives for toners, powder paints, water-dispersible paints, additives for decorative plates, additives for artificial marble, fillers for cosmetics, chromatography It is applied to a wide range of applications such as column fillers and matting agents. It is known that such organic particles can be produced from polydisperse particles having a broad particle size distribution to monodisperse particles having a uniform particle size by production methods such as suspension polymerization, emulsion polymerization, seed polymerization, and dispersion polymerization. .

  When such organic particles are used for applications such as decorative board additives and matting agents, the refractive index of the organic particles is important. In addition, when the organic particles as described above are used for actual applications, the organic particles are dispersed in a solvent such as water or an organic solvent and used as a dispersion, or a resin component such as a binder resin is further added to the dispersion. In addition, it is often used as a paint. Therefore, when organic particles are mixed with a solvent or a binder resin to prepare a dispersion such as a dispersion or paint, it is possible to maintain a uniform dispersion state without aggregation of organic particles in the dispersion. It is extremely important from the viewpoint of stability and handleability.

  On the other hand, when the dispersion containing the above organic particles is applied to the surface of the substrate, the organic particles are deposited on the surface of the substrate as the solvent evaporates. The state was reflected in the dispersed state of the particles on the substrate surface. In general, as a means for aggregating organic particles, a method of adding an aggregating agent to a dispersion is known (for example, Patent Documents 1 to 5). There was a problem that sedimentation of particles became remarkable and a dispersion having a uniform particle concentration could not be obtained.

  Patent Document 6 discloses a light diffusion sheet including a transparent base material and a light diffusion layer laminated on at least one surface of the transparent base material, and the light diffusion layer includes a transparent binder resin and a resin. And a crosslink obtained by copolymerizing a monomer composition in which the resin particles contain a (meth) acrylic acid ester having a cyclic saturated hydrocarbon group in the molecule and a crosslinkable monomer. A light diffusing sheet characterized by being resin particles is disclosed. According to this technique, it is known that a light diffusing sheet including a light diffusing layer containing resin particles that hardly causes scratches on the light diffusing layer and hardly causes coating unevenness when the light diffusing layer is formed is known. However, the crosslinked resin particles described in Patent Document 6 have a problem that secondary particles cannot be formed by aggregating particles on the surface of the substrate.

JP-A-5-40366 Japanese Patent Laid-Open No. 5-178912 JP-A-6-256438 JP-A-8-183807 JP 2001-114902 A JP 2008-185813 A

  The present invention has been made in view of the above circumstances, and the object of the present invention is to stably disperse the organic particles-containing composition without mixing when the organic particle-containing composition is prepared by mixing with a solvent or the like. When the solvent is volatilized from the particle-containing composition, organic particles that aggregate by the interaction of organic particles to form secondary particles without adding an additive such as an aggregating agent, and such organic particles are contained. An object is to provide a composition containing organic particles.

  The organic particles of the present invention that were able to solve the above problems are organic particles obtained by polymerizing the monomer composition, have a particle size variation coefficient of 20% or less, and a hydrophobicity index of 35. It is characterized by being -65.

  When organic particles having a hydrophobicity index in the above range are mixed with a solvent or the like to prepare an organic particle-containing composition, almost all organic particles are stably dispersed as primary particles in the solvent without aggregation. Nevertheless, when the solvent is volatilized from the organic particle-containing composition, the organic particles self-aggregate due to the interaction between the organic particles to form secondary particles, and the primary particles are almost absent. . Moreover, if the variation coefficient of a particle diameter is 20% or less, the self-aggregation property between organic particles will become favorable. As a result, the organic particles of the present invention can aggregate to form secondary particles by the interaction of the organic particles without adding an additive such as an aggregating agent.

  The organic particles of the present invention are non-crosslinkable (meth) acrylic monomers having at least one selected from the group consisting of linear alkyl groups having 4 to 10 carbon atoms, branched alkyl groups and cyclic alkyl groups. What is obtained by polymerizing a monomer composition containing s is preferable. At least one selected from the group consisting of a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group, and a cyclic alkyl group in 100% by mass of all monomers contained in the monomer composition; The content of the non-crosslinkable (meth) acrylic monomer is preferably 5% by mass or more. The organic particles preferably have an organic polymer skeleton and a polysiloxane skeleton. The organic particles of the present invention preferably have an average particle size of 0.5 μm to 40 μm.

  Moreover, the organic particle containing composition containing the said organic particle and a solvent is also contained in this invention. The organic particle-containing composition preferably further contains a binder resin.

  According to the present invention, when an organic particle-containing composition is prepared by mixing with a solvent or the like, it is stably dispersed without agglomeration. When the solvent is volatilized from the organic particle-containing composition, the organic particles interact with each other. Organic particles that aggregate to form secondary particles are obtained.

It is a microscope observation photograph after the solvent drying of the organic particle containing composition using the organic particle 1 of this invention. It is the microscope observation photograph after the solvent drying of the organic particle containing composition using the organic particle 12 for a comparison.

  The organic particles of the present invention are organic particles obtained by polymerizing a monomer composition, and have a particle diameter variation coefficient of 20% or less and a hydrophobicity index of 35 to 65. .

  The organic particles are not particularly limited as long as they are obtained by polymerizing a monomer composition, and examples thereof include organic polymer particles and organic-inorganic composite particles.

  Examples of the organic polymer particles include linear polymers such as polystyrene, polymethyl methacrylate, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polysulfone, polycarbonate, and polyamide; divinylbenzene, hexatriene, divinyl ether, divinylsulfone, and diallyl. Carbinol, alkylene diacrylate, polyalkylene glycol diacrylate, polyalkylene glycol dimethacrylate, alkylene triacrylate, alkylene tetraacrylate, alkylene trimethacrylate, alkylene tetramethacrylate, alkylene bisacrylamide, alkylene bismethacrylamide, both end acrylic modified polybutadiene oligomer Etc. alone or other polymerizable Reticulated polymer obtained by mer polymerization; and the like made of such particles; amino compound (e.g., benzoguanamine, melamine or urea, etc.) organic polymer comprising an amino resin obtained by polycondensation reaction of formaldehyde.

  Examples of organic / inorganic composite particles include particles formed by combining metalloxane chains (molecular chains including “metal-oxygen-metal” bonds) such as (organo) polysiloxanes and polytitanoxanes with organic molecules at the molecular level; methyltrimethoxysilane, etc. Particles such as polymethylsilsesquioxane obtained by hydrolysis of organoalkoxysilane, and condensation reaction; polysiloxane and hydrolyzable silicon group-containing polysiloxane and polymerizable group (for example, vinyl group, ( And particles obtained by reacting with a polymerizable monomer having a (meth) acryloyl group).

Hydrophobic index It is essential that the organic particles of the present invention have a hydrophobic index of 35 or more and 65 or less. If the hydrophobicity index is 65 or less, when the organic particle-containing composition is prepared by mixing the organic particles with a solvent or the like, the dispersion stability of the organic particles in the organic particle-containing composition is increased, and 35 or more. If so, the interaction between the organic particles is enhanced and self-aggregation is exhibited.

  Here, in the present invention, self-aggregation refers to a coagulant or the like when an organic particle is mixed with a solvent to prepare an organic particle-containing composition and then the solvent is volatilized from the organic particle-containing composition. Even if the additive is not added, the secondary particles are formed by agglomeration due to the interaction between organic particles. In the present application, the state in which secondary particles are formed means a state in which substantially all organic particles are aggregated in units of 5 or more and are present on the surface of the substrate.

  The hydrophobicity index of the organic particles is preferably 37 or more, more preferably 40 or more, and preferably 63 or less, more preferably 60 or less. The hydrophobicity index of the organic particles is an index indicating the hydrophobicity of the organic particles and can be measured by a method described later. The hydrophobicity index of the organic particles can be adjusted as appropriate by controlling the type and composition ratio of the monomers constituting the organic particles and the average particle diameter of the organic particles.

Monomer composition The monomer composition used in the present invention will be described. The monomer composition contains a monomer as an essential component.

  The monomer composition is a non-crosslinkable (meth) acrylic monomer having at least one selected from the group consisting of a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group and a cyclic alkyl group. It is preferable that the body (hereinafter, also referred to as “specific organic group-containing monomer”) is included. Here, non-crosslinkable is a monomer that does not have two or more polymerizable groups such as vinyl groups in one molecule.

  By including the specific organic group-containing monomer, the hydrophobicity index of the obtained organic particles can be easily adjusted. In addition, since the specific organic group-containing monomer is non-crosslinkable, a skeleton of a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group, or a cyclic alkyl group to be introduced is present in the organic particles. It is hard to receive restraint. As a result, the intermolecular interaction necessary for the expression of self-aggregation works effectively.

  Examples of the linear alkyl group having 4 to 10 carbon atoms include an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, and an n-decyl group. Etc. Examples of the branched alkyl group having 4 to 10 carbon atoms include t-butyl group, isobutyl group, isopentyl group, t-pentyl group, neopentyl group, isohexyl group, isoheptyl group, isooctyl group, isononyl group, and isodecyl group. Is mentioned. Examples of the cyclic alkyl group having 4 to 10 carbon atoms include a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, an isobornyl group, and a 4-t-butylcyclohexyl group. Any of these alkyl groups has an effect on the expression of the self-aggregation property of the present invention, but a linear alkyl group and a branched alkyl group are preferred in order to make the intermolecular interaction work more effectively.

  Examples of the specific organic group-containing monomer include (meth) acrylic acid having at least one selected from the group consisting of a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group, and a cyclic alkyl group. Mention may be made of esters. Specifically, t-butyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate , (Meth) acrylic acid alkyl esters such as nonyl (meth) acrylate, decyl (meth) acrylate, 2-ethylhexyl (meth) acrylate; cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cycloheptyl (meth) (Meth) acrylic acid cycloalkyl esters such as acrylate, cyclooctyl (meth) acrylate, isobornyl (meth) acrylate, and 4-t-butylcyclohexyl (meth) acrylate. These specific organic group-containing monomers may be used alone or in combination of two or more. These specific organic group-containing monomers are all effective for the self-aggregation of the present invention, but in the organic particle production method described later, the specific organic group-containing monomer is stably contained in the organic particles. T-butyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate in that the body can be incorporated and the intermolecular interaction works more effectively. Is preferred. In the present application, (meth) acrylic acid refers to acrylic acid, methacrylic acid and a mixture thereof, and (meth) acrylate refers to acrylate, methacrylate and a mixture thereof.

  When the specific organic group-containing monomer is used, the content of the specific organic group-containing monomer in 100% by mass of all monomers contained in the monomer composition is preferably 5% by mass or more, more preferably. Is 10% by mass or more, preferably 90% by mass or less, and more preferably 85% by mass or less. By setting the content of the specific organic group-containing monomer to 5% by mass or more, the interaction between the obtained organic particles can be further increased, the self-aggregation property can be improved, and 90% by mass or less. By doing this, it is possible to further suppress the aggregation between particles during the polymerization reaction when producing the organic particles.

  The monomer composition preferably contains a non-crosslinkable styrenic monomer. By containing a styrene-based monomer, the refractive index of the organic particles can be controlled, and the resulting organic particles can be suitably used for applications such as decorative board additives and matting agents. Examples of the styrene monomer include styrene, o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, p-methoxy styrene, pt-butyl styrene, p-phenyl styrene, o-Chlorostyrene, m-chlorostyrene, p-chlorostyrene, p-hydroxystyrene and the like can be mentioned. These styrene monomers may be used alone or in combination of two or more. Of these, styrene is preferred.

  When the styrene monomer is used, the content of the styrene monomer in 100% by mass of the total monomer contained in the monomer composition is preferably 5% by mass or more, more preferably 10% by mass. As mentioned above, More preferably, it is 15 mass% or more, 90 mass% or less is preferable, More preferably, it is 85 mass% or less, More preferably, it is 80 mass% or less. By setting the content of the styrene monomer to 5% by mass or more, the refractive index of the organic particles can be easily controlled, and by setting it to 90% by mass or less, the interaction between the organic particles decreases. Without self-aggregation.

  The monomer composition preferably contains a silane monomer. By containing a silane monomer, a polysiloxane skeleton can be introduced into the organic particles. The silane monomer is not particularly limited as long as it can form a siloxane bond, and examples thereof include hydrolyzable silicon compounds represented by the following formula (1) and derivatives thereof. .

R ' _m SiX _4-m (1)
(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.)

  Examples of the silane monomer represented by the formula (1) include tetrafunctional silane monomers such as tetramethoxysilane and tetraethoxysilane; trifunctional monomers such as methyltrimethoxysilane and methyltriethoxysilane. Silane-based monomers; bifunctional silane-based monomers such as dimethyldimethoxysilane and dimethyldiethoxysilane; monofunctional silane-based monomers such as trimethylmethoxysilane and trimethylethoxysilane.

  The derivative of the silicon compound represented by the formula (1) 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. Examples thereof include a compound and a low condensate obtained by partially hydrolyzing the silane compound.

  As the silane monomer, a crosslinkable silane monomer having a polymerizable reactive group capable of forming an organic polymer skeleton is preferable. Examples of the polymerizable reactive group possessed by the crosslinkable silane monomer include radical polymerizable groups, epoxy groups, hydroxyl groups, amino groups represented by the following formulas (2), (3) and (4): Can be mentioned.

^{_{CH 2 = C (-R a)}} -COOR b - (2)
(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)}} - (3)
(In the formula, R ^c represents a hydrogen atom or a methyl group.)

^{_{CH 2 = C (-R d)}} -R e - (4)
(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 represented by the formula (2) include an acryloxy group and a methacryloxy group. Examples of the radical polymerizable group of the formula (3) include a vinyl group and an isopropenyl group. Examples of the radical polymerizable group of the formula (4) include a vinylphenyl group and an isopropenylphenyl group.

  Examples of the crosslinkable silane monomer include 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 1-hexenyltrimethoxysilane, 1- Having radically polymerizable groups such as hexenyltriethoxysilane; containing epoxy groups such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane And the like; those containing a hydroxyl group such as 3-hydroxypropyltrimethoxysilane; those containing an amino group such as 3-aminopropyltrimethoxysilane and 3-aminopropyltriethoxysilane; These crosslinkable silane monomers may be used alone or in combination of two or more. Among these crosslinkable silane monomers, those having a radical polymerizable group are preferred.

  The silane monomer may be used alone or in combination of two or more. Among these, since polysiloxane particles having a more uniform particle diameter can be obtained when producing seed particles using a silane-based monomer, m = 1 in the formula (1), and X A trifunctional silane monomer in which is a methoxy group or an ethoxy group is preferred. Therefore, as the silane monomer, trifunctional silane monomers such as methyltrimethoxysilane and phenyltrimethoxysilane; 3- (meth) acryloxypropyltrimethoxysilane, vinyltrimethoxysilane, β- (3 , 4-epoxycyclohexyl) ethyltrimethoxysilane and other trifunctional crosslinkable silane monomers are preferred, particularly 3- (meth) acryloxypropyltrimethoxysilane, vinyltrimethoxysilane and the like having a polymerizable reactive group. Trifunctional crosslinkable silane monomers are preferred.

  In addition, if only the silicon compound and its derivative in which m = 3 in the formula (1) is used as the silane monomer, a polysiloxane skeleton cannot be obtained. Therefore, when it is desired to introduce a polysiloxane skeleton into the organic particles, it is necessary to contain a silicon compound in which m = 0, 1, 2 in the formula (1) and a derivative thereof as a silane monomer.

When the silane monomer is used, the content of SiO _{2 in} the finally obtained organic particles is preferably 0.1% by mass or more with respect to the total mass of the organic particles, more preferably 1 It is at least mass%, preferably at most 25 mass%, more preferably at most 10 mass%. If the content of SiO ₂ in the organic particles is in the above range, organic particles having a narrow particle size distribution can be obtained, and the solvent resistance is excellent, and the self-aggregation property of the organic particles by the specific organic group-containing monomer. Can be efficiently exhibited. Incidentally, SiO ₂ content in the organic particles is a mass percentage determined by measuring the mass before and after firing at at 800 ° C. or higher temperatures in an oxidizing atmosphere such as an organic particulate air.

  The monomer composition preferably includes a crosslinkable vinyl monomer. The crosslinkable vinyl monomer is a crosslinkable monomer having two or more vinyl groups in one molecule. Specifically, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) ) Acrylate, trimethylolpropane tri (meth) acrylate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, decaethylene glycol di (meth) acrylate, pentadecaethylene glycol di (Meth) acrylate, Penta contactor ethylene glycol di (meth) acrylate, 1,3-butylene di (meth) acrylate, allyl (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythri Polyfunctional (meth) acrylates such as tetral (meth) acrylate and dipentaerythritol hexa (meth) acrylate; aromatic divinyl compounds such as divinylbenzene, divinylnaphthalene and derivatives thereof; N, N-divinylaniline, divinyl ether And crosslinking agents such as divinyl sulfide and divinyl sulfonic acid. These crosslinkable vinyl monomers may be used alone or in combination of two or more. Among these, polyfunctional (meth) acrylates and aromatic divinyl compounds are preferable, and ethylene glycol di (meth) acrylate and divinylbenzene are particularly preferable.

  When the crosslinkable monomer is used, the content of the crosslinkable monomer in 100% by mass of the total monomer contained in the monomer composition is preferably 5% by mass or more, more preferably 10% by mass or more. More preferably, it is 15 mass% or more, 65 mass% or less is preferable, More preferably, it is 55 mass% or less, More preferably, it is 45 mass% or less. By setting the content of the crosslinkable monomer to 5% by mass or more, the solvent resistance of the obtained organic particles is improved, and the organic particles swell when mixed with a solvent to prepare an organic particle-containing composition. It becomes difficult to suppress the aggregation of organic particles in the organic particle-containing composition, and by setting it to 65% by mass or less, the density of the obtained organic particles does not become too high, and the organic particle-containing composition Sedimentation of organic particles in can be suppressed. The crosslinkable monomer is preferably the crosslinkable silane monomer or the crosslinkable vinyl monomer.

  The monomer composition contains a monomer other than the specific organic group-containing monomer, the non-crosslinkable styrene monomer, the silane monomer, and the crosslinkable vinyl monomer. However, it is most preferable that the monomer contains only the specific organic group-containing monomer, the non-crosslinkable styrene monomer, the silane monomer, and the crosslinkable vinyl monomer. .

  Examples of the other monomer used in the monomer composition include (meth) acrylic acid; methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, undecyl (meth) acrylate, dodecyl (meth) ) (Meth) acrylic acid alkyl ester having a linear alkyl group having 1 to 3 carbon atoms or 11 or more carbon atoms such as acrylate; cyclopropyl (meth) acrylate, cycloundecyl (meth) acrylate, cyclododecyl (meth) (Meth) acrylic acid cycloalkyl ester having a cyclic alkyl group having 3 or 11 carbon atoms such as acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) ) (Meth) ax such as acrylate Le hydroxyalkyl ester; phenyl (meth) acrylate, benzyl (meth) acrylate, tolyl (meth) acrylate, and aromatic acrylate monomers, such as phenethyl (meth) acrylate. These other monomers may be used alone or in combination of two or more.

  The monomer composition may contain various additives as necessary, for example, pigments, plasticizers, fluorescent brighteners, magnetic powders, ultraviolet absorbers, antistatic agents, flame retardants, and the like. May be added. The amount of these additives used is preferably 0.01 to 10 parts by mass, more preferably 0.1 parts by mass with respect to 100 parts by mass of all monomers contained in the monomer composition. -5 parts by mass, more preferably 0.5-3 parts by mass.

  The organic particles of the present invention preferably have an organic polymer skeleton and a polysiloxane skeleton.

  As the form of the organic polymer skeleton, a polymer having a main chain composed of a repeating unit represented by the following formula (5) (so-called vinyl polymer) because the hardness of the organic particles can be appropriately controlled. ) Is preferable. The organic polymer skeleton includes a radical polymerizable group possessed by a specific organic group-containing monomer, a non-crosslinkable styrene monomer, a crosslinkable vinyl monomer, and a crosslinkable silane monomer. Those obtained by polymerization are preferred.

  The polysiloxane skeleton is a skeleton formed by continuously chemically bonding siloxane units represented by the following formula (6). The polysiloxane skeleton is preferably obtained by a hydrolytic condensation reaction of a silicon compound having a hydrolyzable group.

  Organic particles having an organic polymer skeleton and a polysiloxane skeleton (hereinafter sometimes referred to as “composite particles”) are particles having a polysiloxane skeleton using a silane monomer (hereinafter referred to as “polysiloxane particles”). And using the polysiloxane particles as seed particles, the specific organic group-containing monomer, the non-crosslinkable styrene monomer, the crosslinkable vinyl monomer, and other single monomers. The monomer composition containing a monomer can be obtained by seed polymerization in which polymerization is performed after the polysiloxane particles have absorbed the monomer composition.

  As an aspect of the composite particle, an aspect in which at least one carbon atom in the organic polymer skeleton and a silicon atom in the polysiloxane skeleton are bonded to each other is preferable. Specifically, the organic group of the silicon atom in the polysiloxane skeleton and the carbon atom in the organic polymer skeleton are bonded to each other, so that the polysiloxane skeleton and the organic polymer skeleton have a three-dimensional network structure. The aspect which comprises is preferable. That is, a polysiloxane skeleton containing a radical polymerizable group is formed using a crosslinkable silane monomer having a radical polymerizable group as a silane monomer, and the radical polymerizable group that the polysiloxane skeleton has, What is obtained by polymerizing the specific organic group-containing monomer and the like is preferable.

  Specifically, using a crosslinkable silane monomer, a polysiloxane particle containing a radical polymerizable group is prepared, and using the obtained radical polymerizable group-containing polysiloxane particle as a seed particle, the specific organic group containing Obtained by seed polymerization, in which a monomer composition containing a monomer, a non-crosslinkable styrene monomer, a crosslinkable vinyl monomer, and another monomer is absorbed by polysiloxane particles and then polymerized. Are preferred.

Particle Physical Properties The shape of the organic particles of the present invention is not particularly limited. For example, the shape may be any of a spherical shape, a spheroid shape, a confetti shape, a thin plate shape, a needle shape, and an eyebrow shape. A spherical shape is preferred. The average particle size of the organic particles is preferably 0.5 μm or more, more preferably 1.0 μm or more, further preferably 1.5 μm or more, preferably 40 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. It is. By making the average particle diameter of the organic particles 0.5 μm or more, the organic particles can be more uniformly dispersed when preparing the organic particle-containing composition by mixing the organic particles and the solvent, and is 40 μm or less. By setting it as this, sedimentation of the organic particle in the organic particle containing composition after preparation can be suppressed. Here, the “average particle size” in the present invention refers to the number average particle size, and is a precision particle size distribution measuring apparatus using the Coulter principle (for example, trade name “Coulter Multisizer III type”, Beckman Coulter, Inc. The value measured by

The variation coefficient in the particle diameter of the organic particles of the present invention is preferably 20% or less, more preferably 15% or less, still more preferably 10% or less, and most preferably 8% or less. When the variation coefficient of the particle diameter exceeds 20%, the self-aggregation property between the organic particles may be lowered. The reason why the self-aggregation property of the organic particles decreases due to the increase in the coefficient of variation of the particle diameter is not necessarily clear, but if the variation of individual organic particles is large, the surface area of the organic particles also varies. It is considered that the interaction between the organic particles becomes non-uniform and the self-aggregation property is lowered. Here, in the present invention, the variation coefficient of the particle diameter is obtained by applying the average particle diameter of organic particles measured by a precision particle size distribution measuring apparatus using the Coulter principle and the standard deviation of the particle diameter of organic particles to the following equation. This is the value obtained by
Coefficient of variation of organic particles (%) = 100 × standard deviation of particle diameter / average particle diameter

  The refractive index of the organic particles of the present invention is preferably 1.50 or more, preferably 1.62 or less, more preferably 1.60 or less. If the refractive index of the organic particles is within the above range, for example, the organic particles can obtain better light scattering characteristics for optical applications.

  The true specific gravity of the organic particles of the present invention is preferably 1.00 (g / cc) to 1.50 (g / cc), more preferably 1.00 (g / cc) to 1.40 (g). / Cc), more preferably 1.00 (g / cc) to 1.35 (g / cc). If the true specific gravity is less than 1.00 (g / cc), the self-aggregation effect by the alkyl group may be insufficient due to the influence of buoyancy on the particles in the composition containing the particles. On the other hand, when the true specific gravity exceeds 1.50 (g / cc), the self-aggregation effect may be insufficient due to the influence of particle sedimentation due to gravity.

Manufacturing method of organic particle The manufacturing method of the organic particle of this invention is demonstrated. The method for producing organic particles of the present invention includes a step of polymerizing the monomer composition. As the polymerization mode of the monomer, hydrolysis condensation is suitable for the polymerization of the silane monomer, and the specific organic group-containing monomer, non-crosslinkable styrene monomer, crosslinkable vinyl monomer. Radical polymerization is suitable for the polymerization of the radical polymerizable group possessed by the monomer and the crosslinkable silane monomer. As the polymerization method, conventionally known polymerization methods such as suspension polymerization, seed polymerization, dispersion polymerization, and emulsion polymerization can be employed. Among these, organic particles having a narrow particle size distribution are obtained, and the specific organic group Seed polymerization is preferable because the monomer can be efficiently incorporated into the particles.

Seed Polymerization Method A method for producing organic particles when the seed polymerization method is employed will be described. The production method by the seed polymerization method has a seed particle production process, an absorption process, and a polymerization process.

  The seed particle manufacturing step is a step of manufacturing seed particles used in the seed polymerization method using a part of the monomer used in the monomer composition.

  As the seed particles, for example, polysiloxane particles obtained from the silane monomer, polystyrene particles obtained from the non-crosslinkable styrene monomer, and the like are preferably used. Among these, polysiloxane particles are preferred because the polysiloxane skeleton can be easily introduced into the obtained organic particles, and in particular, organic particles in which the polysiloxane skeleton and the organic polymer skeleton constitute a three-dimensional network structure are produced. Since it can do, the radically polymerizable group containing polysiloxane particle obtained from a crosslinkable silane monomer is suitable.

  The polysiloxane particles used as seed particles can be obtained by hydrolyzing the silane monomer in a solvent containing water to cause a condensation polymerization reaction. 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, and 1,4-butanediol; acetone And 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.

  When performing hydrolysis and condensation, an emulsifier may be used in combination. Examples of the emulsifier include water-soluble polymers, anionic surfactants, cationic surfactants, zwitterionic surfactants and nonionic surfactants. Examples of the anionic surfactant include fatty acid oils such as sodium oleate and castor oil potassium; alkyl sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate; polyoxyethylene distyryl phenyl ether sulfate ammonium salt, polyoxyethylene disulfide Polyoxyethylene distyryl phenyl ether sulfate such as sodium styryl phenyl ether sulfate; alkyl benzene sulfonate such as sodium dodecylbenzene sulfonate; alkyl naphthalene sulfonate, alkane sulfonate, dialkyl sulfosuccinate, alkyl phosphorus Acid ester salt, naphthalenesulfonic acid formalin condensate, polyoxyethylene alkylphenyl ether sulfate ester salt, polyoxyethylene alcohol Such as Le sulfate 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. Examples of the nonionic surfactant 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 -An oxypropylene block polymer etc. are mentioned. Examples of the water-soluble polymer include polyvinyl alcohol, gelatin, tragacanth, starch, methyl cellulose, carboxymethyl cellulose, hydroxyethyl cellulose, sodium polyacrylate, and sodium polymethacrylate. These emulsifiers may be used alone or in combination of two or more. Among these, an anionic surfactant is preferable because stability between particles during polymerization can be further increased.

  Hydrolysis and condensation are performed at a temperature of 0 ° C. or higher and 100 ° C. or lower, preferably 0 ° C. or higher and 70 ° C. or lower, after mixing the raw material silane monomer and a solvent containing a catalyst, water, and an organic solvent for 30 minutes. It can be performed by stirring for 100 hours or less.

  The polystyrene particles used as seed particles are obtained by polymerizing a non-crosslinkable styrene monomer, and as the polymerization method, a conventionally used method can be adopted, for example, soap-free polymerization, dispersion Polymerization etc. are mentioned.

  The absorption step is a step of causing the seed particles to absorb the remaining monomer composition excluding the monomer used for producing the seed particles. The method for absorbing the monomer composition is not particularly limited as long as the absorption proceeds in the presence of the monomer composition in the presence of the seed particles. For example, the monomer composition may be added to a solvent in which seed particles are dispersed, or the seed particles may be added to a solvent containing the monomer composition. In particular, when polysiloxane particles are used as seed particles, the monomer composition is added to the reaction liquid without removing the polysiloxane particles obtained by hydrolysis and condensation reaction from the reaction liquid (polysiloxane particle dispersion). The method of adding is preferable because the process is not complicated and the productivity is excellent.

  In the absorption step, the monomer composition is absorbed in the structure of the seed particles. The concentration of the seed particles and the monomer composition is set so that the absorption of the monomer composition proceeds promptly. In addition, it is preferable to set the processing method and means for mixing, the temperature and time at the time of mixing, the processing method and means after mixing, and the like under the conditions. The necessity of these conditions may be appropriately considered depending on the seed particles to be used and the kind of monomer contained in the monomer composition. These conditions may be applied singly or in combination of two or more.

  The charging amount of the monomer composition in the absorption step is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and 50 parts by mass or less with respect to 1 part by mass of the seed particles. Is preferable, more preferably 40 parts by mass or less, still more preferably 30 parts by mass or less. 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 the absorption step, the timing of addition of the monomer composition is not particularly limited, and the monomer composition 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 monomer composition, it may be added only by the monomer composition, or a solution of the monomer composition may be added. It is preferable to mix the monomer emulsion emulsified and dispersed in an aqueous medium with the seed particles because absorption into the seed particles is more efficiently performed.

  Although the said emulsifier is not specifically limited, For example, the thing similar to the emulsifier used when performing the said hydrolysis and condensation can be used. Among these, anionic surfactants and nonionic surfactants are preferable because they can stabilize the dispersion state of seed particles and seed particles that have absorbed the monomer composition. These emulsifiers may be used alone or in combination of two or more.

  The amount of the emulsifier used is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, with respect to 100 parts by mass of the total mass of monomers contained in the monomer composition. More preferably, it is 1 mass part or more, It is preferable to set it as 10 mass parts or less, More preferably, it is 8 mass parts or less, More preferably, it is 5 mass parts or less. When the amount of the emulsifier used is less than 0.01 parts by mass, a stable monomer emulsion may not be obtained. When the amount exceeds 10 parts by mass, emulsion polymerization may occur as a side reaction. is there. About the said emulsification dispersion | distribution, it is usually preferable to make the said monomer composition into an emulsion state in water using a homomixer, an ultrasonic homogenizer, etc. with an emulsifier.

  Moreover, when emulsifying and dispersing the monomer composition 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 monomer composition. 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 depending on the seed particles to be used and the type of monomer contained in the monomer composition. These conditions may be used alone or in combination of two or more. Good.

  In the absorption step, for determining whether the monomer composition is absorbed by the seed particles, for example, before adding the monomer composition and after completion of the absorption step, observe the particles with a microscope, and determine the monomer composition. It can be easily determined by confirming that the particle size is increased by absorption of the object.

  The polymerization step is a step in which the monomer composition is subjected to a polymerization reaction. The polymerization reaction is not particularly limited, and for example, any of a method using a polymerization initiator, a method of irradiating ultraviolet rays or radiation, a method of applying heat, and the like can be adopted.

  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-butylperoxide, 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- Dimethylvaleronitrile), 2,2′-azobis (2,3-dimethylbutyronitrile), 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,3,3- Trimethylbutyronitrile), 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-sia Pentanoic 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 amount of the polymerization initiator used is preferably 0.001 parts by mass or more, more preferably 0.01 parts by mass with respect to 100 parts by mass of the total mass of monomers contained in the monomer composition. Part or more, more preferably 0.1 part by weight or more, preferably 20 parts by weight or less, more preferably 10 parts by weight or less, and still more preferably 5 parts by weight or less. When the usage-amount of the said polymerization initiator is less than 0.001 mass part, the polymerization degree of a monomer may not rise. The method of charging the polymerization initiator into the solvent is not particularly limited, and is a method in which the entire amount is charged first (before the start of the reaction) (a mode in which the polymerization initiator is emulsified and dispersed together with the monomer composition, monomer composition) A mode in which a polymerization initiator is charged after the product is absorbed); a method in which a part is charged first, and the rest is continuously fed, or a pulse is added intermittently, or a combination thereof, Any conventionally known method can be employed.

  The reaction temperature during the 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 solvent resistance of the organic particles tends to decrease. On the other hand, if the reaction temperature is too high, aggregation between particles tends to occur during the polymerization. Tend to be. 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 or less, More 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.

  The organic particles produced in the polymerization step can be recovered by cooling the reaction liquid after polymerization and then performing filtration. In addition, you may perform centrifugation as a method of taking out particle | grains. In addition, when a large amount of surfactant remains on the surface of the organic particles, a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group and a cyclic alkyl group derived from the specific organic group-containing monomer. In other words, the effect of self-aggregation, that is, the manifestation of self-aggregation may be insufficient. Therefore, it is preferable to wash the organic particles after production. Water or various organic solvents can be used for washing the organic particles. Among these, it is preferable to wash with water, alcohols such as methanol and ethanol, or a mixed solution thereof.

Organic particle-containing composition The organic particle-containing composition of the present invention will be described. The organic particle-containing composition of the present invention is characterized by containing the organic particles and a solvent.

  Since the organic particles are stably dispersed in the solvent and have self-aggregation properties, the organic particle-containing composition can be obtained by simply volatilizing the solvent without adding a flocculant or the like. Particles can be formed. Specifically, for example, by simply applying the organic particle-containing composition to a substrate and volatilizing the solvent in the organic particle-containing composition, secondary particles of organic particles are spotted on the surface of the substrate. The matte effect by the organic particles can be easily expressed.

  Examples of the solvent include alcohols such as methanol, ethanol, isopropanol, n-butanol, isobutanol, sec-butanol, t-butanol, pentanol, ethylene glycol, propylene glycol, 1,4-butanediol; acetone, Mention may be made of ketones such as methyl ethyl ketone; aromatic hydrocarbons such as toluene. These solvents may be used alone or in combination of two or more.

  Further, the organic particle-containing composition of the present invention may further contain a binder resin in addition to the organic particles and the solvent. The binder resin is not particularly limited, and any binder resin can be used according to required properties such as transparency, organic 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, an organic binder resin such as synthetic rubber or natural rubber, an inorganic binder, or 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, n-butyl (meth) acrylate, isobutyl (meth) ) Acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, cyclododecyl (meth) acrylate, t-butylcyclohexyl (meth) acrylate, lauryl (meth) acrylate, It is a (meth) acrylic polymer containing structural units derived from isobornyl (meth) acrylate, stearyl (meth) acrylate, 2-ethylhexyl (meth) acrylate and the like. 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 thereof include monofunctional monomers such as ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, and N-vinylpyrrolidone; trimethylolpropane 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, neopentyl glycol di ( And polyfunctional monomers such as (meth) acrylate.

Other Components In addition, the organic particle-containing composition of the present invention contains other components in addition to the organic particles, the solvent, and the binder resin as necessary, as long as the effects of the present invention are not impaired. Also good. Examples of other components include a crosslinking agent, a photopolymerization initiator, a leveling agent, an inorganic filler, a pigment, a dye, a plasticizer, a polymerization stabilizer, an antioxidant, a fluorescent whitening agent, an ultraviolet absorber, and an antistatic agent. It is done. These may use only 1 type and may use 2 or more types together.

  By containing the crosslinking agent, the polymer in the binder resin can be crosslinked by the crosslinking agent. The amount of the crosslinking agent component used, addition method, dispersion method and the like are not particularly limited. As the crosslinking agent, for example, when the binder resin has a hydroxyl group, a polyfunctional isocyanate may be used.

  When an ultraviolet curable resin is used as the binder resin, it is preferable to add a photopolymerization initiator. 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 an organic particle containing composition, it is preferable to use a photosensitizer together. Examples of the photosensitizer include n-butylamine, triethylamine, and poly-n-butylphosphine.

  By adding the leveling agent, when coating the organic particle-containing composition on the base film or during drying, it effectively prevents the inhibition of curing due to oxygen on the coating film surface and improves the scratch resistance. Can be made. 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.

  By adding the inorganic filler, the refractive index of the cured layer formed from the organic particle-containing composition can be increased. When adding an inorganic filler, it is preferable that the addition amount of an inorganic filler shall be 10 mass% or more of the solid content total mass of an organic particle containing composition, More preferably, it is 20 mass% or more, More preferably, it is 30 mass% or more. It is preferably 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.

  The organic particle content in the organic particle-containing composition of the present invention is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, still more preferably 5.0% by mass or more, and 80% by mass or less. Is preferable, more preferably 70% by mass or less, and still more preferably 60% by mass or less. If the organic particle content is 0.5% by mass or more, the organic particle density in the organic particle-containing composition does not become too low, and better secondary particles can be formed by self-aggregation. For example, the organic particle density in the organic particle-containing composition does not become too high, and the organic particles can be more favorably dispersed in the composition preparation stage.

  The secondary particles formed by volatilizing the solvent from the organic particle-containing composition preferably have 5 or more, more preferably 10 or more primary particles constituting each secondary particle. It is. When the number of primary particles constituting the secondary particles is in the above range, the matting effect by the organic particles becomes better. The number of primary particles constituting the secondary particles obtained from the organic particle-containing composition is appropriately adjusted by changing the organic particle content, the type of solvent and binder resin, etc. in the organic particle-containing composition. can do.

Applications The organic particles and organic particle-containing composition of the present invention are suitable for light diffusing media such as cosmetics, matte films, mat films, light diffusing films, light diffusing plates with light diffusing films, reflecting films, and antireflection antiglare films. Used for.

  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.

(1) Average particle diameter The average particle diameter and standard deviation of organic particles were measured using a precision particle size distribution measuring apparatus (trade name “Coulter Multisizer III”, manufactured by Beckman Coulter, Inc.). Moreover, the coefficient of variation of the particle diameter of the organic particles was calculated from the obtained measurement results using the following formula.
Coefficient of variation (%) = 100 × (standard deviation / average particle size)

(2) Refractive index An organic particle dispersion was prepared by dispersing 0.5 g of organic particles in 40 g of carbon disulfide. Next, while stirring the organic particle dispersion using a stirrer, ethanol was added dropwise to the organic particle dispersion, and ethanol was added dropwise until the organic particle dispersion was judged visually transparent. Carbon disulfide--corresponding to the mass ratio of ethanol / carbon disulfide at the time when the organic particle dispersion became transparent, from the mass of ethanol dropped until the organic particles became transparent and the mass of carbon disulfide (40 g) An ethanol mixture was prepared, the refractive index of this mixture was measured with an Abbe refractometer (NAR-1T, manufactured by Atago Co., Ltd.), and the obtained value was taken as the refractive index of the organic particles.

(3) Hydrophobic index 50 ml of ion-exchanged water is put into a 200 ml glass beaker having a stirrer placed at the bottom, and 0.2 g of organic particles are floated on the water surface, and then the stirrer is gently rotated. Thereafter, the tip of the burette is submerged in water in a beaker, and methanol is gradually introduced from the buret 5 minutes after the addition of the organic particles while gently rotating the stirring bar. Methanol was introduced 1 ml at a time, and every 1 ml of methanol was stirred for 3 minutes, and 1 ml was then introduced. Continue to introduce methanol until the total amount of organic particles on the water surface completely sinks into the water (with no organic particles floating on the water surface), and the amount of methanol introduced (ml) when the organic particles completely sink into the water. The hydrophobicity index was determined based on the following equation.
Hydrophobicity index (%) = 100 × methanol introduction amount (ml) / (amount of ion exchange water (ml) + methanol introduction amount (ml))
In addition, before adding methanol from a buret, when the organic particle which floated on the water surface completely settled in water, the hydrophobicity index was determined to be 0.

(4) Dispersion stability in organic particle-containing composition and agglomeration after solvent drying The organic particle-containing composition is observed with a microscope, and the dispersion stability of organic particles in the organic particle-containing composition is as follows. It was evaluated with. Next, the organic particle-containing composition was subjected to bar coater no. 10 was applied onto a polyethylene terephthalate (PET) film and allowed to stand to dry the solvent. After the solvent was dried, the cohesiveness of the organic particles was observed with a microscope and evaluated according to the following criteria.
Dispersion stability in evaluation reference composition ○: Most particles are not aggregated and uniformly dispersed as primary particles, and no sedimentation of particles is observed. Δ: Primary particles and secondary particles are mixed, or some particles are settled.
X: Most particles aggregate to form secondary particles.
Aggregability after drying of solvent ○: Most particles are aggregated to form secondary particles.
X: Most particles are dispersed individually and exist as primary particles.

Production Example 1
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 are added. -Polysiloxane that is added to 20 parts by mass of methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd., KBM-503) from the dropping port, and hydrolyzes and condenses 3-methacryloxypropyltrimethoxysilane to become seed particles Particles were prepared. Two hours after the start of the reaction, an emulsion of the obtained polysiloxane particles was sampled, and the particle size was measured by Coulter Multisizer III (manufactured by Beckman Coulter, Inc.). The number average particle size was 1.2 μm. .

  Subsequently, a monomer obtained by dissolving 2.0 parts by mass of polyoxyethylene styrenated phenyl ether sulfate ammonium salt (Daiichi Kogyo Co., Ltd., Hightenol NF-08) with 175 parts by mass of ion-exchanged water as an emulsifier was used. 165 parts by mass of styrene (St), 65 parts by mass of t-butyl methacrylate (t-BMA), 70 parts by mass of ethylene glycol dimethacrylate (EGDMA), 2,2′-azobis (2,4- Dimethylvaleronitrile) (Wako Pure Chemical Industries, Ltd., V-65) was added to a solution in which 2 parts by mass was dissolved, and a monomer emulsion was prepared by emulsifying and dispersing at 6000 rpm for 5 minutes with a TK homomixer (made by Tokushu Kika Kogyo Co., Ltd.). The resulting monomer emulsion was added to the emulsion of polysiloxane particles and further stirred.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 polysiloxane particles were enlarged by absorbing the monomer composition.

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 composition. After the reaction solution was cooled, it was filtered using quantitative filter paper (manufactured by Advantech Toyo Co., Ltd., quantitative filter paper No. 5C), and a cake of the polymerization product was collected by filtration. Next, the obtained cake was washed with methanol, filtered again, and the cake collected by filtration was dried at 100 ° C. for 6 hours. The dried particles were pulverized at a pulverization pressure of 4 kgf / cm ² with a pulverizer (manufactured by Nippon Pneumatic Kogyo Co., Ltd., “Supersonic Jet Crusher for Laboratory LJ Type”) to obtain organic particles 1. The monomer composition of the obtained organic particles 1 and each evaluation result are shown in Table 1.

Production Example 2
Organic particles 2 were obtained in the same manner as in Production Example 1, except that ion-exchanged water was changed to 426 parts by mass and methanol was changed to 218 parts by mass.

Production Example 3
Organic particles 3 were obtained in the same manner as in Production Example 1, except that ion-exchanged water was changed to 376 parts by mass and methanol was changed to 268 parts by mass.

Production Example 4
Organic as in Production Example 1 except that the monomer was changed to 190 parts by mass of styrene (St), 40 parts by mass of t-butyl methacrylate (t-BMA), and 70 parts by mass of ethylene glycol dimethacrylate (EGDMA). Particle 4 was produced. Table 1 shows the monomer composition of the obtained organic particles 4 and the evaluation results.

Production Example 5
Organic in the same manner as in Production Example 1 except that the monomer was changed to 210 parts by mass of styrene (St), 20 parts by mass of t-butyl methacrylate (t-BMA), and 70 parts by mass of ethylene glycol dimethacrylate (EGDMA). Particle 5 was produced. The monomer composition of the obtained organic particles 5 and each evaluation result are shown in Table 1.

Production Example 6
Organic as in Production Example 1 except that the monomer was changed to 165 parts by mass of styrene (St), 65 parts by mass of n-butyl methacrylate (n-BMA), and 70 parts by mass of ethylene glycol dimethacrylate (EGDMA). Particle 6 was prepared. The monomer composition of the obtained organic particles 6 and each evaluation result are shown in Table 1.

Production Example 7
Except that the monomer was changed to 103 parts by mass of styrene (St), 175 parts by mass of cyclohexyl methacrylate (CHMA), and 22 parts by mass of divinylbenzene (manufactured by Nippon Steel Chemical Co., Ltd., DVB960), the same as in Production Example 1 Thus, organic particles 7 were produced. The monomer composition of the obtained organic particles 7 and the evaluation results are shown in Table 1.

Production Example 8
Production Example 1 except that the monomers were changed to 103 parts by mass of styrene (St), 175 parts by mass of 2-ethylhexyl acrylate (2EHA), and 22 parts by mass of divinylbenzene (manufactured by Nippon Steel Chemical Co., Ltd., DVB960). In the same manner, organic particles 8 were produced. The monomer composition of the obtained organic particles 8 and each evaluation result are shown in Table 1.

Production Example 9
The same procedure as in Production Example 1 except that the monomer was changed to 103 parts by mass of styrene (St), 175 parts by mass of lauryl methacrylate (LMA), and 22 parts by mass of divinylbenzene (manufactured by Nippon Steel Chemical Co., Ltd., DVB960). Thus, organic particles 9 were produced. Table 1 shows the monomer composition of the obtained organic particles 9 and the evaluation results.

Production Example 10
In a four-necked flask equipped with a condenser, thermometer, and dripping port, 90 parts by mass of ion-exchanged water, 10 parts by mass of styrene, 0.5 parts by mass of n-decyl mercaptan, and 0.1 parts by mass of NaCl were added for 1 hour. To replace the nitrogen in the reactor. Thereafter, the temperature of the reaction solution was raised to 70 ° C., and then an ion exchange aqueous solution in which 0.1 part by mass of potassium persulfate was dissolved was poured into the reaction solution using a syringe. Then, reaction was performed at 70 degreeC for 24 hours. After completion of the reaction, the obtained emulsion was subjected to solid-liquid separation, and the obtained cake was washed with ion-exchanged water and methanol to prepare polystyrene particles serving as seed particles. When the obtained polystyrene particles were measured by Coulter Multisizer III (manufactured by Beckman Coulter, Inc.), the average particle diameter was 1.2 μm, and the coefficient of variation of the particles was 8.9%.

  To a four-necked flask equipped with a condenser, a thermometer, and a dropping port, add 0.5 parts by mass of the polystyrene particles obtained above, 50 parts by mass of ion-exchanged water, and 0.05 parts by mass of sodium lauryl sulfate, and uniformly disperse them. It was. Furthermore, 20 mass parts of 3 mass% aqueous solution of polyvinyl alcohol was added and stirred to prepare a dispersion of polystyrene particles.

  Subsequently, 3.80 parts by mass of styrene (St) as a monomer and t-butyl methacrylate (t-BMA) were dissolved in a solution in which 0.1 part by mass of sodium lauryl sulfate as an emulsifier was dissolved in 50 parts by mass of ion-exchanged water. 8.68 parts by mass, ethylene glycol dimethacrylate (EGDMA) 1.41 parts by mass, a solution prepared by dissolving 0.70 parts by mass of benzoyl peroxide as a polymerization initiator was added and emulsified and dispersed with a homogenizer to prepare a monomer emulsion. The obtained monomer emulsion was added to the polystyrene particle dispersion prepared above and further stirred.

  Next, the reaction solution was heated to 70 ° C. in a nitrogen atmosphere and held at 70 ° C. for 2 hours to perform radical polymerization of the monomer composition. After the reaction solution was cooled, it was filtered using a quantitative filter paper (manufactured by Advantech Toyo Co., Ltd., quantitative filter paper No. 5C), and the polymerization product was collected by filtration. The obtained cake was washed with ion-exchanged water and methanol, and vacuum-dried at 80 ° C. for 12 hours to obtain organic particles 10. Table 1 shows the monomer composition of the obtained organic particles 10 and the evaluation results.

Production Example 11
Except for changing monomers to 1.80 parts by mass of styrene (St), 8.86 parts by mass of cyclohexyl methacrylate (CHMA), and 1.41 parts by mass of divinylbenzene (manufactured by Nippon Steel Chemical Co., Ltd., DVB960). Organic particles 11 were produced in the same manner as in Production Example 9. The monomer composition of the obtained organic particles 11 and each evaluation result are shown in Table 1.

Production Example 12
The organic particles 12 were produced in the same manner as in Production Example 1 except that the monomers were changed to 165 parts by mass of styrene (St), 65 parts by mass of methyl methacrylate (MMA), and 70 parts by mass of ethylene glycol dimethacrylate (EGDMA). did. The monomer composition of the obtained organic particles 12 and each evaluation result are shown in Table 1.

Production Example 13
The same procedure as in Production Example 1 except that the monomer was changed to 103 parts by mass of styrene (St), 175 parts by mass of methyl methacrylate (MMA), and 22 parts by mass of divinylbenzene (manufactured by Nippon Steel Chemical Co., Ltd., DVB960). Thus, organic particles 13 were produced. The monomer composition of the obtained organic particles 13 and each evaluation result are shown in Table 1.

Production Example 14
The monomer was 165 parts by mass of styrene (St), light ester L-8 (manufactured by Kyoeisha Chemical Co., Ltd., alkyl (12 to 15 carbon atoms) methacrylate) (L-8) 65 parts by mass, ethylene glycol dimethacrylate ( EGDMA) Organic particles 14 were produced in the same manner as in Production Example 1 except that the amount was changed to 70 parts by mass. The monomer composition of the obtained organic particles 14 and the evaluation results are shown in Table 1.

Production Example 15
Monomers are 165 parts by mass of styrene (St), light ester IM-A (manufactured by Kyoeisha Chemical Co., Ltd., isomyristyl acrylate (carbon number 14)) (IMA) 65 parts by mass, ethylene glycol dimethacrylate (EGDMA) 70 parts by mass Organic particles 15 were produced in the same manner as in Production Example 1 except that the above was changed. The monomer composition of the obtained organic particles 15 and each evaluation result are shown in Table 1.

Production Example 16
Except that the monomer was changed to 3.8 parts by mass of styrene (St), 8.86 parts by mass of methyl methacrylate (MMA), and 1.41 parts by mass of ethylene glycol dimethacrylate (EGDMA), the same as in Production Example 9. Thus, organic particles 16 were produced. The monomer composition of the obtained organic particles 16 and each evaluation result are shown in Table 1.

Production Example 17
Except for changing the monomer to 3.8 parts by mass of styrene (St), 8.86 parts by mass of light ester L-8 (manufactured by Kyoei Chemical Co., Ltd.), and 1.41 parts by mass of ethylene glycol dimethacrylate (EGDMA). Organic particles 17 were produced in the same manner as in Production Example 9. The monomer composition of the obtained organic particles 17 and the evaluation results are shown in Table 1.

  The organic particles 1 to 11 are all monomers containing a specific organic group (non-crosslinkable (meth) acrylic having a linear alkyl group, a branched alkyl group or a cyclic alkyl group having 4 to 10 carbon atoms). System monomer). These organic particles 1 to 11 had a hydrophobicity index of 37 to 61. The organic particles 12, 13, and 16 contain a non-crosslinkable methacrylic acid monomer having a linear alkyl group having a carbon number of less than 4 as a monomer. The value was as low as 30. The organic particles 14, 15 and 17 contain a non-crosslinkable (meth) acrylic monomer having a linear alkyl group, branched alkyl group or cyclic alkyl group having more than 10 carbon atoms as a monomer. In all cases, the hydrophobicity index was a high value of 70 to 74.

Production Example 18
The organic particle-containing composition was prepared by sufficiently mixing the organic particles 1 to 17 obtained above, the solvent, and the binder resin so as to have the composition shown in Table 2. For each organic particle-containing composition, the dispersion stability in the organic particle-containing composition and the cohesiveness after solvent drying were evaluated, and the results are shown in Table 3.

MEK: methyl ethyl ketone IPA: isopropyl alcohol TMP-A: trimethylolpropane triacrylate

  The organic particle-containing composition using the organic particles 1 to 11 having a hydrophobicity index of 35 to 65 can stabilize the dispersion of the organic particles in the composition regardless of whether toluene, methyl ethyl ketone, or isopropyl alcohol is used as a solvent. The property was good. Further, the organic particle-containing composition using these organic particles 1 to 11 had good dispersion stability of the organic particles in the composition even when trimethylolpropane triacrylate was further contained as a binder.

  And the organic particle containing composition using said organic particles 1-11 was all good in the cohesiveness of the organic particle after solvent drying. A microscope observation photograph (taken at a magnification of 1000) of the organic particle-containing composition (formulation No. 1-1) using the organic particles 1 after solvent drying is shown in FIG. It was confirmed that most of the organic particles aggregated to form secondary particles.

  The organic particle-containing composition using the organic particles 12, 13, 16 having a hydrophobicity index of less than 35 is a dispersion of the organic particles in the composition regardless of whether toluene, methyl ethyl ketone, or isopropyl alcohol is used as a solvent. Stability was good. In addition, the organic particle-containing composition using these organic particles 12, 13, 16 has good dispersion stability of the organic particles in the composition even when trimethylolpropane triacrylate is further contained as a binder. It was. However, all of the organic particle-containing compositions using these organic particles 12, 13, and 16 have poor aggregation properties of the organic particles after solvent drying. A microscope observation photograph (taken at a magnification of 1000 times) after solvent drying of the organic particle-containing composition (formulation No. 1-1) using the organic particles 12 is shown in FIG. It was confirmed that most organic particles were dispersed individually without agglomeration and existed as primary particles.

  The organic particle-containing composition using the organic particles 14, 15, and 17 having a hydrophobicity index exceeding 65 is a dispersion of the organic particles in the composition regardless of whether toluene, methyl ethyl ketone, or isopropyl alcohol is used as a solvent. Stability was bad. Moreover, the organic particle containing composition using these organic particles 14, 15, and 17 had poor dispersion stability of the organic particles in the composition even when trimethylolpropane triacrylate was further contained as a binder. In addition, the organic particle containing composition using these organic particles 14, 15, and 17 had good cohesiveness of the organic particles after solvent drying.

  The organic particles and organic particle-containing composition of the present invention can be used for light diffusion media such as cosmetics, matte films, mat films, light diffusion films, light diffusion plates with light diffusion films, reflection films, and antireflection antiglare films. .

The present invention relates to organic particles child.

The present invention has been made in view of the above circumstances, and the object of the present invention is to stably disperse the organic particles-containing composition without mixing when the organic particle-containing composition is prepared by mixing with a solvent or the like. When the solvent is volatilized from the particle-containing composition, and to provide an organic particle child to coagulate and form a secondary particle by interaction of the organic particles be additive without adding such flocculants.

Organic particles children of the present invention, the cosmetic, matte film, or matte film, light diffusion film, the light diffusion layer with light diffusing plate, a reflective film, can be used in the light diffusing medium such as an anti-reflection anti-glare film.

Claims (7)

Organic particles obtained by polymerizing the monomer composition,
An organic particle having a coefficient of variation in particle diameter of 20% or less and a hydrophobicity index of 35 to 65.   Non-crosslinkable (meth) acrylic monomer having at least one selected from the group consisting of a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group and a cyclic alkyl group. The organic particle according to claim 1, comprising a body.   At least one selected from the group consisting of a linear alkyl group having 4 to 10 carbon atoms, a branched alkyl group, and a cyclic alkyl group in 100% by mass of all monomers contained in the monomer composition; The organic particles according to claim 1 or 2, wherein the content of the non-crosslinkable (meth) acrylic monomer is 5% by mass or more.   The organic particle according to any one of claims 1 to 3, which has an organic polymer skeleton and a polysiloxane skeleton.   The organic particles according to any one of claims 1 to 4, having an average particle diameter of 0.5 to 40 µm.   The organic particle containing composition characterized by including the organic particle and solvent as described in any one of Claims 1-5.   Furthermore, the organic particle containing composition of Claim 6 containing binder resin.