WO2018055786A1 - Polymer particle dispersion, and polymer particles, dispersant, and dispersion medium used therein, as well as uses of these - Google Patents

Abstract

Provided are: a polymer particle dispersion having exceptional redispersibility; polymer particles, a dispersant, and a dispersion medium used therein; and the uses of these. Provided is a polymer particle dispersion in which polymer particles are dispersed in an aqueous medium, wherein: the concentration of the polymer particles is 50% by weight or less; an amino-based silane coupling agent, and a surfactant that has a polyoxyethylene chain and/or a phosphoric acid ester moiety, are bonded to the polymer particle surface; the bonded surfactant content per unit surface area of the polymer particle surface is 0.6-15.0 mg/m²; and the bonded amino-based silane coupling agent content per unit surface area of the polymer particle surface is 0.05-3.0 mg/m². Also provided is a dispersant that contains the reaction product of an amino-based silane coupling agent and a surfactant that has a polyoxyethylene chain and/or a phosphoric acid ester moiety.

Description

Polymer particle dispersion, polymer particles used therefor, dispersant and dispersion medium, and uses thereof

The present invention relates to a polymer particle dispersion in which polymer particles are dispersed in a dispersion medium such as an aqueous medium, polymer particles used in the polymer particle dispersion, and a dispersant used in the polymer particle dispersion. In addition, the present invention relates to a dispersion medium, a coating agent using the polymer particle dispersion, an antiblocking agent, and a pore former, and an optical film using the polymer particles.

Conventionally, polymer particle dispersions in which polymer particles are dispersed in an aqueous medium have been used as coating agents such as optical film coating agents and antiblocking agents. For example, conventionally, as a method for producing an optical film provided with a coating containing polymer particles, a polymer particle dispersion in which polymer particles are uniformly dispersed in a mixed solution containing an aqueous medium and a binder resin is used as a coating agent. A method of manufacturing an optical film by coating on a base film is used. Such polymer particle dispersions may be used after being stored for a long period (for example, several months), so that the dispersion stability is such that the polymer particles do not become difficult to disperse during a long storage period. Therefore, it is required that the polymer particles have properties capable of being redispersed to a uniform concentration during use.

The polymer particle dispersion is preferably excellent in dispersion stability and excellent in redispersibility, which is a property of dispersing at a uniform concentration during redispersion. A polymer particle dispersion that forms a strong deposit or a polymer particle dispersion that is highly cohesive will greatly impair the redispersibility.

The sedimentation rate of the polymer particles in the polymer particle dispersion can be calculated according to the following Stokes theorem, and tends to increase in proportion to the particle diameter of the polymer particles and the density of the polymer particles. Therefore, especially when this sedimentation rate is high, if the polymer particle dispersion is stored in a storage container, a deposit of polymer particles is formed on the bottom surface of the storage container, and the concentration of the polymer particles is uneven. Phenomenon that tends to occur. As a means for re-homogenizing (re-dispersing) the concentration of the polymer particles, a mixing method using a homogenizer or the like can be mentioned.

Particularly in the case of polymer particles having a low uniformity of particle diameter (for example, polymer particles having a coefficient of variation of particle diameter of more than 15%), it is easy to form a strong polymer particle deposit during sedimentation. Dispersion / pulverization unevenness may occur, and a polymer particle dispersion in which polymer particles are dispersed at a uniform concentration may not be obtained.

Usually, polymer particles having a particle size in the sub-micron region (several hundred nm or more and less than 1 μm) have a slow sedimentation rate and a Brownian motion action. Therefore, polymer particles in which such polymer particles are dispersed The dispersion is easy to ensure dispersion stability. However, since it is impossible to reduce the sedimentation rate of the polymer particles to zero, a polymer in which polymer particles having a particle diameter of such a submicron region (several hundred nm to 1.0 μm) are dispersed is used. Even in the case of a particle dispersion, the polymer particles gradually settle with time and form polymer particle deposits. Further, when the polymer particles in the submicron region are deposited, the deposition density is high and a stronger polymer particle deposit is formed.

Regarding the cohesiveness of the polymer particle dispersion liquid, it may aggregate over time depending on the type (polarity, SP (solubility parameter) value, viscosity, etc.) of the aqueous medium used as the dispersion medium and the storage environment (temperature, etc.). In some cases, redispersion during mixing or the like is difficult. For example, when the temperature of the polymer particle dispersion containing a surfactant is low, the surfactant is precipitated and tends to aggregate.

Examples of techniques for imparting dispersion stability to the polymer particle dispersion include addition of organic and inorganic dispersants and surfactants, and modification with a coupling agent.

By adding the surfactant, it is possible to obtain an effect of imparting dispersion stability to the polymer particle dispersion and suppressing aggregation of the polymer particles due to the electrostatic repulsion action and steric hindrance of the surfactant. . However, once the polymer particles settle and deposit in the polymer particle dispersion, the surfactant firmly adheres between the polymer particles, making it difficult to redisperse the polymer particles. There is a problem.

As the coupling agent, a silanol-based silane coupling agent is generally exemplified. The silane coupling agent can impart dispersion stability by a condensation reaction (chemical modification) with the polymer particle surface.

Patent Document 1 describes a spacer for a liquid crystal display element, the surface of which is coated with a thin film made of a silane coupling agent having a group having a dipole moment of 1 to 5 debyes, and the spacer is made of a polymer. Is described.

In Patent Document 2, polymer particles are contained in 2 to 30% by weight of a surfactant, 5 to 20% by weight of an emulsified wax, 0.2 to 1.0% by weight of a base, 30 to 80% by weight of an additive, and 5% by weight of water. % Or less and less than 40% by weight, and an silane coupling agent is described as an example of the additive.

Patent Document 3 discloses conductive fine particles comprising spherical core particles, an elastic coating layer formed on the surface of the spherical core particles, and a conductive thin film layer formed on the surface of the elastic coating layer. A method for producing conductive microparticles, the layer of which is formed by the following process, is described.
(A) A step of imparting a hydrophobic functional group to the surface of a spherical core particle made of a metal oxide or a resin by a silane coupling agent treatment (b) The hydrophobic spherical core particle is made into water and / or an organic solvent. A step of preparing a dispersion of hydrophobic spherical core particles by dispersing (c) a step of adding a surfactant to the hydrophobic spherical core particle dispersion (d) a dispersion of hydrophobic spherical core particles to which a surfactant has been added From the hydrolytic polycondensation product of the organosilicon compound on the surface of the hydrophobic spherical core particles by adding one or a mixture of two or more of the organosilicon compounds represented by the following formula (2) to the liquid and further adding an alkali A step of forming an elastic covering layer R ¹ _n Si (OR ² ) _4-n (2)
(Wherein n is an integer of 1 to 3, R ¹ is a hydrocarbon having 1 to 10 carbon atoms selected from a substituted or unsubstituted hydrocarbon group, and R ² is a hydrogen atom, having 1 to 5 carbon atoms. An alkyl group or an acyl group having 2 to 5 carbon atoms)

In Patent Document 4, 10 to 45 parts by weight of a monomer mixture containing 50% by weight or more of methyl methacrylate is emulsion-polymerized in the presence of at least water, a surfactant and a polymerization initiator, and then the reaction product is subjected to emulsion polymerization. Coating composition containing 55 to 90 parts by weight of a monomer mixture containing 35 to 70% by weight of cyclohexyl (meth) acrylate and / or methyl methacrylate and 0.1 to 3% by weight of a silane coupling agent. A method for producing an aqueous polymer dispersion is described.

JP-A-6-180456 JP-T-3-504393 Japanese Patent No. 4860587 JP 2002-12601 A

However, according to the study of the present inventor, as in Patent Document 1, it is not possible to obtain polymer particles excellent in redispersibility simply by chemically modifying the polymer particles with a silane coupling agent. I understood.

In addition, Patent Document 2 does not disclose or suggest what kind of compound should be used as a coupling agent for silanes. According to the study of the present inventor, a polymer having excellent redispersibility by using a general silane coupling agent (for example, a vinyl silane coupling agent such as vinyltrimethoxysilane) together with a surfactant. It turned out that particles could not be obtained.

Patent Documents 3 and 4 describe vinyl-based silane coupling agents such as vinyltrimethoxysilane as silane coupling agents. According to the study of the present inventor, it has been found that polymer particles excellent in redispersibility cannot be obtained only by using a vinyl silane coupling agent together with a surfactant.

The present invention has been made in view of the above-described conventional problems, and the object thereof is a polymer particle dispersion excellent in redispersibility, polymer particles used in the polymer particle dispersion, and the polymer particle dispersion. It is an object to provide a dispersing agent and a dispersion medium used in the above, a coating agent using the polymer particle dispersion, an antiblocking agent, a pore-forming agent, and an optical film using the polymer particles.

The inventor of the present application has studied the improvement of redispersibility of the polymer particle dispersion using a silane coupling agent, and as a result, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety and an amino-based silane coupling. By adding an agent, polymer particles are coated with an appropriate amount of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety and an amino silane coupling agent, and exhibits excellent redispersibility. The present inventors have found that a polymer particle dispersion can be obtained and have completed the present invention.

The polymer particle dispersion according to the first aspect of the present invention is a polymer particle dispersion in which polymer particles are dispersed in an aqueous medium, and the concentration of the polymer particles is 50% by weight or less. Yes, a surface active agent having at least one of a polyoxyethylene chain and a phosphate ester site and an amino-based silane coupling agent are attached to the surface of the polymer particle, and per unit surface area of the polymer particle surface. The content of the surfactant adhering to the surface is 0.6 to 15.0 mg / m ² , and the content of the amino silane coupling agent adhering per unit surface area of the polymer particle surface The amount is 0.05 to 3.0 mg / m ² .

In the polymer particle dispersion having the above-described structure, 0.6 to 15.0 mg / m ² of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site per unit surface area of the polymer particle surface is adhered. In addition, since the amino silane coupling agent is adhered to 0.05 to 3.0 mg / m ² per unit surface area of the polymer particle surface, aggregation of the polymer particles is sufficiently suppressed. The polymer particle surface is sufficiently hydrophilized. Therefore, the polymer particle dispersion having the above-described configuration is easily redispersed by general mixing such as mixing by a homomixer without forming a strong polymer particle deposit even if it settles. . Therefore, the polymer particle dispersion having the above-described configuration is excellent in redispersibility.

In the polymer particle dispersion according to the second aspect of the present invention, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety is added in an amount of 0.7 to 5.5 based on 100 parts by weight of the polymer particles. It is characterized by containing 0 part by weight and 0.05 to 4.0 parts by weight of an amino silane coupling agent with respect to 100 parts by weight of the polymer particles.

The polymer particle dispersion liquid having the above-described structure contains 0.7 to 5.0 parts by weight of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site with respect to 100 parts by weight of the polymer particles, and By including 0.05 to 4.0 parts by weight of the amino silane coupling agent with respect to 100 parts by weight of the polymer particles, aggregation of the polymer particles is sufficiently suppressed and the surface of the polymer particles is sufficiently Hydrophilized. Therefore, the polymer particle dispersion having the above-described configuration is easily redispersed by general mixing such as mixing by a homomixer without forming a strong polymer particle deposit even if it settles. . Therefore, the polymer particle dispersion having the above-described configuration is excellent in redispersibility.

The dispersant of the present invention is characterized in that it contains a reaction product of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent.

The dispersant of the present invention is a substance that disperses a target substance (dispersoid) that does not mix and disperse in a hydrophilic dispersion medium (medium in which the target substance is to be dispersed) alone. It has a function of assisting in uniform dispersion without agglomeration in the dispersion medium. Therefore, the dispersing agent of the present invention is prepared by dispersing polymer particles in a dispersion medium of at least one of water and a polar organic solvent (an organic solvent such as alcohol) to produce a polymer particle dispersion. It has a useful function for the purpose of uniforming the dispersion and stabilizing the dispersion without agglomerating the polymer particles during the polymerization reaction.

The dispersion medium of the present invention is characterized by containing at least one of water and a polar organic solvent and the dispersant of the present invention.

The dispersion medium of the present invention has a useful function for the purpose of uniformly dispersing polymer particles to produce a polymer particle dispersion and for stabilizing the dispersion without agglomerating the polymer particles during the polymerization reaction. ing. In the present application documents, “polar organic solvent” means an organic compound having a solubility parameter calculated by the Fedors method of 20.5 (MPa) ^1/2 (10 (cal / cm ³ ) ^1/2 ) or more. It shall refer to the solvent.

The polymer particle dispersion according to the third aspect of the present invention is characterized in that polymer particles are dispersed in the dispersion medium of the present invention. The polymer particle dispersion having the above-described configuration uses the dispersion medium of the present invention containing a reaction product of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent. Therefore, aggregation of the polymer particles is suppressed and the surface of the polymer particles is hydrophilized. Therefore, the polymer particle dispersion having the above-described configuration is easily redispersed by general mixing such as mixing by a homomixer without forming a strong polymer particle deposit even if it settles. . Therefore, the polymer particle dispersion having the above-described configuration is excellent in redispersibility.

The coating agent of the present invention is characterized by containing the polymer particle dispersion according to any one of the first to third aspects of the present invention and a binder. Since the coating agent having the above-described configuration contains the polymer particle dispersion of the present invention, it is excellent in redispersibility.

The anti-blocking agent of the present invention is characterized by containing the polymer particle dispersion according to any one of the first to third aspects of the present invention. Since the anti-blocking agent having the above-described configuration contains the polymer particle dispersion of the present invention, it is excellent in redispersibility.

The pore former of the present invention is characterized by containing the polymer particle dispersion according to any one of the first to third aspects of the present invention. Since the anti-blocking agent having the above-described configuration contains the polymer particle dispersion of the present invention, it is excellent in redispersibility.

In the polymer particle of the present invention, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent are attached to the surface of the polymer particle. The content of the surfactant attached per unit surface area of the particle surface is 0.6 to 15.0 mg / m ² , and the amino group attached per unit surface area of the polymer particle surface The content of the silane coupling agent is 0.05 to 3.0 mg / m ² .

In the polymer particles having the above structure, 0.6 to 15.0 mg / m ² of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site is attached per unit surface area of the polymer particle surface, In addition, since the amino silane coupling agent is adhered to 0.05 to 3.0 mg / m ² per unit surface area of the polymer particle surface, aggregation of the polymer particles is sufficiently suppressed and the polymer The particle surface is sufficiently hydrophilic. For this reason, the polymer particles having the above-described structure are easily redispersed by general mixing such as mixing by a homomixer without forming a strong polymer particle deposit even when precipitated in an aqueous medium. ing. Therefore, the polymer particles having the above structure are excellent in redispersibility in an aqueous medium.

The optical film of the present invention includes a film substrate and a coating formed on the film, and the coating includes the polymer particles of the present invention and a binder.

The optical film having the above structure can be produced by applying the coating agent of the present invention having excellent redispersibility on a film substrate and drying it, so that a polymer particle uniformly dispersed can be easily produced. .

According to the present invention, polymer particle dispersion excellent in redispersibility, polymer particles used in the polymer particle dispersion, dispersant and dispersion medium used in the polymer particle dispersion, and the polymer particle dispersion It is possible to provide a coating agent, an antiblocking agent and a pore-forming agent using a liquid, and an optical film using the polymer particles.

Hereinafter, the present invention will be described in detail.
(Polymer particle dispersion)
The polymer particle dispersion according to the first aspect of the present invention is a polymer particle dispersion in which polymer particles are dispersed in an aqueous medium, and the concentration of the polymer particles is 50% by weight or less. Yes, a surface active agent having at least one of a polyoxyethylene chain and a phosphate ester site and an amino-based silane coupling agent are attached to the surface of the polymer particle, and per unit surface area of the polymer particle surface. The content of the surfactant adhering to the surface is 0.6 to 15.0 mg / m ² , and the content of the amino silane coupling agent adhering per unit surface area of the polymer particle surface The amount is 0.05 to 3.0 mg / m ² .

The polymer particle dispersion according to the second aspect of the present invention is a polymer particle dispersion in which polymer particles are dispersed in an aqueous medium, and the concentration of the polymer particles is 50% by weight or less. A surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety is contained in an amount of 0.7 to 5.0 parts by weight with respect to 100 parts by weight of the polymer particles, and an amino-based silane coupling agent is added It is contained in an amount of 0.05 to 4.0 parts by weight based on 100 parts by weight of the coalesced particles.

The aqueous medium has water or a solubility parameter (hereinafter referred to as “SP value”) calculated by the Fedors method of 20.5 (MPa) ^1/2 (10 (cal / cm ³ ) ^1/2 ) or more. This is a mixed medium of an organic solvent and water. The specific gravity of the aqueous medium is larger than the specific gravity of the polymer particles (ρ _p > ρ _f ). The organic solvent SP value of 20.5 ^{(MPa) 1/2,} specifically, for example, SP value ^{24.3 (MPa) 1/2 (11.9 (} cal / cm 3) 1 / ² ) isopropyl alcohol, SP value 28.2 (MPa) ^1/2 (13.8 (cal / cm ³ ) ^1/2 ) methyl alcohol, SP value 26.2 (MPa) ^1/2 And ethyl alcohol which is (12.6 (cal / cm ³ ) ^1/2 ).

The polymer particles are at least one of (meth) acrylic polymer, styrene polymer, (meth) acryl-styrene copolymer, polyurethane polymer, polyethylene terephthalate polymer, and silicone polymer. It is preferable that it is comprised.

When the polymer particles are composed of at least one of these, the polymer particles themselves are hydrophobic and difficult to adapt to an aqueous medium. However, in the polymer particle dispersion of the present invention, the polymer particles Since the surface is modified with an amino-based silane coupling agent to be hydrophilized, the polymer particles are easily adapted to an aqueous medium and have excellent redispersibility. Therefore, the effect of the present invention becomes remarkable when the polymer particles are composed of at least one of them.

The polymer constituting the polymer particles is, for example, a vinyl monomer polymer. Examples of the vinyl monomer include a monofunctional vinyl monomer having one ethylenically unsaturated group and a polyfunctional vinyl monomer having two or more ethylenically unsaturated groups. .

Examples of the monofunctional vinyl monomer include, for example, (meth) acrylate monomers; styrene monomers (aromatic vinyl monomers); vinyl acetate, vinyl propionate, vinyl versatate, etc. Saturated fatty acid vinyl monomers; vinyl cyanide monomers such as acrylonitrile and methacrylonitrile; ethylenic unsaturation such as acrylic acid, methacrylic acid, crotonic acid, citraconic acid, itaconic acid, maleic acid and fumaric acid Carboxylic acid; Ethylenically unsaturated carboxylic acid anhydride such as maleic anhydride; Ethylenically unsaturated dicarboxylic acid monoalkyl ester such as monobutylmaleic acid; Ethylenically unsaturated carboxylic acid and ethylenically unsaturated dicarboxylic acid monoalkyl ester Ethylenically unsaturated carboxylates such as ammonium salts or alkali metal salts of Ethylenically unsaturated carboxylic acid amides such as amide, methacrylamide and diacetone acrylamide; N-methylol acrylamide, N-methylol methacrylamide, methylolated diacetone acrylamide, and these monomers and alcohols having 1 to 8 carbon atoms And methylolates of ethylenically unsaturated carboxylic acid amides such as etherified products (eg, N-isobutoxymethylacrylamide) and derivatives thereof.

Examples of the (meth) acrylate monomer include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, isononyl acrylate, acrylic acid Alkyl acrylate monomers such as lauryl and stearyl acrylate; alkyl methacrylate monomers such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-ethylhexyl methacrylate and stearyl methacrylate; glycidyl acrylate (Meth) acrylic acid ester having an epoxy group (glycidyl group) such as glycidyl methacrylate; hydroxyalkyl (meth) acrylate such as 2-hydroxyethyl methacrylate and 2-hydroxypropyl acrylate; dimethyl Amino ethyl methacrylate, having an amino group such as diethylaminoethyl methacrylate (meth) acrylic acid ester. The (meth) acrylic acid ester monomer preferably contains at least one of an alkyl acrylate monomer and an alkyl methacrylate monomer. In this application document, “(meth) acrylate” means acrylate or methacrylate, and “(meth) acryl” means acryl or methacryl.

Examples of the styrenic monomer include styrene, α-methylstyrene, vinyl toluene, and ethyl vinyl benzene.

Examples of the polyfunctional vinyl monomer include allyl (meth) acrylate, divinylbenzene, diallyl phthalate, triallyl cyanurate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, propylene glycol di ( Examples include meth) acrylate, triethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate.

The above-mentioned vinyl monomers may be used alone or in combination of two or more.

The polymer particles are preferably composed of at least one of a (meth) acrylic polymer, a styrene polymer, and a (meth) acryl-styrene copolymer. Thereby, a polymer particle with high light transmittance is realizable. The (meth) acrylic polymer is a polymer of a (meth) acrylic acid ester monomer, or a (meth) acrylic acid ester monomer, a (meth) acrylic acid ester monomer, and styrene. It is a copolymer with a vinyl monomer other than the monomer. The styrene polymer is a polymer of a styrene monomer or a copolymer of a styrene monomer and a vinyl monomer other than a (meth) acrylate monomer and a styrene monomer. It is a polymer. The (meth) acrylic-styrene copolymer is a copolymer of a (meth) acrylic acid ester monomer and a styrene monomer, or a (meth) acrylic acid ester monomer. A copolymer of a styrene monomer and a vinyl monomer other than the (meth) acrylic acid ester monomer and the styrene monomer.

The polymer constituting the polymer particles is preferably a copolymer (crosslinked polymer) of the monofunctional vinyl monomer and the polyfunctional vinyl monomer. Therefore, the polymer particles are particularly preferably composed of at least one of a crosslinked (meth) acrylic polymer, a crosslinked styrene polymer, and a crosslinked (meth) acryl-styrene copolymer. The amount of the structural unit derived from the polyfunctional vinyl monomer in the crosslinked polymer is preferably in the range of 5 to 50% by weight with respect to 100% by weight of the crosslinked polymer. When the quantity of the structural unit derived from the said polyfunctional vinyl-type monomer is less than the said range, the crosslinking degree of the said crosslinked polymer will become low. As a result, when the polymer particle dispersion is mixed with a binder and applied as a resin composition, the polymer particles may swell and increase the viscosity of the resin composition, which may reduce the coating workability. . Furthermore, as a result of the low degree of crosslinking of the crosslinked polymer, the polymer particles dispersion is mixed with a binder and molded (so-called kneading application) when the polymer particles are heated during mixing or molding. The polymer particles are easily dissolved or deformed. When the amount of the structural unit derived from the polyfunctional vinyl monomer is larger than the above range, the improvement in the effect commensurate with the use amount of the polyfunctional vinyl monomer is not recognized, and the production cost increases. There is.

The concentration of the polymer particles in the polymer particle dispersion is 50% by weight or less. When the concentration of the polymer particles is more than 50% by weight, the polymer particles are too much to disperse and the dispersibility and redispersibility are poor. The concentration of the polymer particles in the polymer particle dispersion is more preferably in the range of 1 to 50% by weight, further preferably in the range of 3 to 50% by weight, and 10 to 50% by weight. Most preferably within the range.

[Surfactant]
The surfactant having at least one of the polyoxyethylene chain and the phosphate ester moiety is preferably at least one of an anionic surfactant having a polyoxyethylene chain and a nonionic surfactant having a polyoxyethylene chain. The anionic surfactant having a polyoxyethylene chain and the nonionic surfactant having a polyoxyethylene chain are sufficiently adsorbed on the surface of the polymer particle by being adsorbed on the surface of the polymer particle. As a result, the redispersibility can be further improved.

Further, as the surfactant having at least one of the polyoxyethylene chain and the phosphate ester moiety, a surfactant having a phosphate ester moiety is preferable, and the surfactant having both the polyoxyethylene chain and the phosphate ester moiety. An agent is more preferable. Thereby, redispersibility can further be improved. When the surfactant has a phosphate ester moiety, the phosphate ester moiety of the surfactant attached to the polymer particle surface and the amino group of the amino silane coupling agent are ionically bonded to form an amino silane coupling. It is considered that the agent can be fixed on the surface of the polymer particles.

Examples of the surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety include an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, and a phosphor having a polyoxyethylene chain and a phosphate ester moiety. Anionic surfactant having no acid ester moiety, Anionic surfactant having a phosphoric ester moiety and no polyoxyethylene chain, Nonionic surfactant having a polyoxyethylene chain, Phosphate ester moiety Examples include amphoteric surfactants.

Examples of the anionic surfactant having both the polyoxyethylene chain and the phosphate ester moiety include polyoxyethylene alkylphenyl such as polyoxyethylene nonylphenyl ether phosphate (for example, polyoxyethylene nonylphenyl ether sodium phosphate). Examples thereof include ether phosphates; polyoxyethylene styrenated phenyl ether phosphates; polyoxyethylene alkyl ether phosphates.

As the anionic surfactant having a polyoxyethylene chain and not having a phosphoric acid ester moiety, any known anionic surfactant such as a fatty acid salt type, a sulfate ester salt type, or a sulfonate type may be used. For example, polyoxyethylene alkyl phenyl ether sulfate ester salt; polyoxyethylene alkyl ether sulfate salt such as sodium polyoxyethylene lauryl ether sulfate; polyoxyethylene alkyl sulfate ester; polyoxyethylene styrenated phenyl ether sulfate ammonium salt, etc. Examples include polyoxyethylene styrenated phenyl ether sulfate salts.

Examples of the anionic surfactant having a phosphate ester moiety and no polyoxyethylene chain include alkyl phosphate ester salts such as sodium alkyl (C4) phosphate.

As the nonionic surfactant having a polyoxyethylene chain, any known nonionic surfactant such as an ester type, an ether type, and an ester / ether type can be used. For example, polyoxyethylene tridecyl ether Polyoxyethylene alkyl ethers such as polyoxyethylene alkyl phenyl ethers such as polyoxyethylene octyl phenyl ether, polyoxyethylene styrenated phenyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acids such as polyoxyethylene sorbitan monolaurate Examples thereof include esters, polyoxyethylene alkylamines, and oxyethylene-oxypropylene block polymers. One of these surfactants having at least one of a polyoxyethylene chain and a phosphate ester moiety may be used alone, or two or more thereof may be used in combination.

Examples of the amphoteric surfactant having a phosphate ester moiety include a phosphate ester-based amphoteric surfactant.

The polymer particle dispersion according to the first aspect of the present invention is a content of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site attached per unit surface area of the polymer particle surface. Is 0.6 to 15.0 mg / m ² , preferably 1.0 to 10.0 mg / m ² . When the content of the surfactant having at least one of a polyoxyethylene chain and a phosphate ester site attached per unit surface area of the polymer particle surface is less than 0.6 mg / m ² , the polyoxyethylene chain In addition, the surfactant having at least one of the phosphate ester sites cannot adhere the amino silane coupling agent to the surface of the polymer particles. When the content of the surfactant having at least one of a polyoxyethylene chain and a phosphate ester site attached per unit surface area of the polymer particle surface is more than 15.0 mg / m ² , A surfactant having at least one of an oxyethylene chain and a phosphate ester site strongly adheres between the polymer particles, resulting in poor redispersibility.

The content of the surfactant having at least one of the polyoxyethylene chain and the phosphate ester moiety in the polymer particle dispersion according to the second aspect of the present invention is 0.7 parts by weight with respect to 100 parts by weight of the polymer particles. Although it is ˜5.0 parts by weight, it is more preferably 1.0 to 3.0 parts by weight. When the content of the surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety in the polymer particle dispersion is less than 0.7 parts by weight, at least one of the polyoxyethylene chain and the phosphate ester moiety The surface active agent having the property cannot attach the amino silane coupling agent to the surface of the polymer particles. When the content of the surfactant having at least one of the polyoxyethylene chain and the phosphate ester moiety in the polymer particle dispersion is more than 5.0 parts by weight, the excess polyoxyethylene chain and phosphate ester moiety The surfactant having at least one of the above adheres firmly between the polymer particles, resulting in poor redispersibility.

A surfactant having neither a polyoxyethylene chain nor a phosphate ester group may further adhere to the polymer particle surface. Examples of the surfactant having neither polyoxyethylene chain nor phosphate ester group include anionic surfactants having neither polyoxyethylene chain nor phosphate ester group, nonionic surfactants having no polyoxyethylene chain, Either a cationic surfactant having no oxyethylene chain or an amphoteric surfactant having neither a polyoxyethylene chain nor a phosphate group can be used.

As the anionic surfactant having neither the polyoxyethylene chain nor the phosphate group, any known anionic surfactant such as a fatty acid salt type, a sulfate ester type, and a sulfonate type can be used. For example, fatty acid soap such as sodium oleate and castor oil potassium soap; alkyl sulfate ester salt such as lauryl sulfate (for example, sodium lauryl sulfate, ammonium lauryl sulfate); alkylbenzene sulfonate such as sodium dodecylbenzenesulfonate; alkylnaphthalene Dialkylsulfosuccinates such as sulfonate, alkanesulfonate, di (2-ethylhexyl) sulfosuccinate (sodium salt), dioctylsulfosuccinate (sodium salt); alkenyl succinate (dipotassium salt); naphthalenesulfonic acid Ho Marine condensate, and the like.

As the nonionic surfactant having no polyoxyethylene chain, any known nonionic surfactant such as an ester type, an ether type, an ester / ether type, and the like can be used. For example, the carbon number of an alkylene group And polyoxyalkylene alkyl ethers such as polyoxyalkylene tridecyl ether having 3 or more, sorbitan fatty acid ester, glycerin fatty acid ester and the like.

As the cationic surfactant having no polyoxyethylene chain, any known cationic surfactants such as amine salt type and quaternary ammonium salt type can be used. An activator is advantageous for its handling. Specific examples of the cationic surfactant having no polyoxyethylene chain include alkylamine salts such as laurylamine acetate and stearylamine acetate; lauryltrimethylammonium chloride, hexadecyltrimethylammonium chloride, cocoyltrimethylammonium chloride, dodecyltrimethyl. Examples thereof include alkyltrimethylammonium chlorides such as ammonium chloride; alkyldimethylbenzyl chlorides such as hexadecyldimethylbenzylammonium chloride and lauryldimethylbenzylammonium chloride.

Examples of the amphoteric surfactant having neither the polyoxyethylene chain nor the phosphate group include lauryl dimethylamine oxide, phosphite ester amphoteric surfactant and the like. These surfactants having neither a polyoxyethylene chain nor a phosphate group may be used singly or in combination of two or more.

The content of the surfactant adhering per unit surface area of the polymer particle surface is, for example, the content of the surfactant measured using liquid chromatography mass spectrometry (LC-MS-MS). , By dividing by the specific surface area of the polymer particles measured using the BET method (nitrogen adsorption method).

In the present invention, an amino silane coupling agent is used as the silane coupling agent. The amino-based silane coupling agent has good compatibility with a surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety, and is physically used as a surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety. By fixing by fixing chemically or chemically, the effect of suppressing aggregation of the polymer particles and making the surface of the polymer particles hydrophilic is sufficiently exhibited.

The amino-based silane coupling agent is a silane coupling agent having an amino group (—NH ₂ ) or a substituted amino group. Examples of the amino silane coupling agent include 3- (2-aminoethyl) aminopropyltrimethoxysilane (for example, “XIAMETER (registered trademark) OFS-6020 SILANE” manufactured by Toray Dow Corning Silicone Co., Ltd., “SILQUEST (registered trademark) A-1120 SILANE” “SILQUEST (registered trademark) A-1122 SILANE” manufactured by Momentive Performance Materials, “KBM-603” manufactured by Shin-Etsu Silicone Co., Ltd., Momentive Performance Materials “TSL8340” manufactured by JNC, “Syraace (registered trademark) S310” manufactured by JNC, etc.), 3- (2-aminoethyl) aminopropylmethyldimethoxysilane (for example, Toray Dow Corning Silicone Co., Ltd.) “DOW CORNING (registered trademark) Z-6023 SILANE” manufactured by the company, “KBM-602” manufactured by Shin-Etsu Silicone Co., Ltd., “TSL8345” manufactured by Momentive Performance Materials, Inc., “Syra Ace (registered) by JNC Corporation (Trademark) S310 ")," DOW CORNING (registered trademark) Z-6026 SILANE "(special aminosilane) manufactured by Toray Dow Corning Silicone Co., Ltd., N-β- (N-vinylbenzylaminoethyl) -γ-amino Propyltrimethoxysilane hydrochloride (for example, “DOW CORNING (registered trademark) Z-6032 SILANE” manufactured by Toray Dow Corning Silicone Co., Ltd.), “DOW CORNING (registered trademark) manufactured by Toray Dow Corning Silicone Co., Ltd. Z- 050 SILANE ”(special aminosilane), γ-anilinopropyltrimethoxysilane (for example,“ DOW CORNING (registered trademark) Z-6883 SILANE ”manufactured by Toray Dow Corning Silicone Co., Ltd.,“ KBM ”manufactured by Shin-Etsu Silicone Co., Ltd. -573 ", etc.), 3-aminopropyltriethoxysilane (for example," SILQUEST (registered trademark) A-1100 SILANE "" SILQUEST (registered trademark) A-1102 SILANE "manufactured by Momentive Performance Materials, Shin-Etsu Silicone "KBE-903" manufactured by JNC Corporation, "Syra Ace (registered trademark) S330" manufactured by JNC Corporation, etc.), 3-aminopropyltrimethoxysilane (for example, "KBM-903" manufactured by Shin-Etsu Silicone Co., Ltd.), JNC Corporation “Silaace (registered trademark) S360” manufactured by the company), 3- (trihydroxysilyl) propan-1-amine (for example, “SILQUEST (registered trademark) A-1106 SILANE” manufactured by Momentive Performance Materials) 3-ureidopropyltriethoxysilane (for example, “SILQUEST (registered trademark) A-1160 SILANE” manufactured by Momentive Performance Materials), N-aminoethyl-γ-aminopropylethyldimethoxysilane, N-aminoethyl -Γ-aminopropylpropyldimethoxysilane, N-aminoethyl-γ-aminopropylbutyldimethoxysilane, aminopropylmethyldimethoxysilane, aminopropylethyldimethoxysilane, aminopropylbutyldimethoxysilane , Aminopropyl phenyl dimethoxy silane, N- aminoethyl -γ- aminopropyl phenyl dimethoxy silane, aminoethyl methyl dimethoxy silane, amino ethyl propyl dimethoxy silane, aminoethyl butyl dimethoxysilane include aminoethyl phenyl dimethoxy silane. As the amino-based silane coupling agent, one having an amino group (—NH ₂ ), that is, a primary amine is more preferable. These amino-based silane coupling agents may be used alone or in combination of two or more.

The amino silane coupling agent is preferably an amino silane coupling agent having a solubility in water of 1.0% by weight or more. By using an amino silane coupling agent having a solubility in water of 1.0% by weight or more, the surface of the polymer particles can be made more hydrophilic, so that the redispersibility can be further improved. Examples of amino silane coupling agents having a water solubility of 1.0% by weight or more include “XIAMETER (registered trademark) OFS-6020 SILANE”, “DOW CORNING (registered trademark) Z-6023 SILANE”, and “DOW CORNING”. (Registered trademark) Z-6026 SILANE "," DOW CORNING (registered trademark) Z-6050 SILANE "(both have a solubility in water of 5% by weight or more).

In the polymer particle dispersion according to the first aspect of the present invention, the content of the amino silane coupling agent attached per unit surface area of the polymer particle surface is 0.05 to 3.0 mg / m ² but preferably 0.05 to 2.0 mg / m ² . When the content of the amino silane coupling agent attached per unit surface area of the polymer particle surface is less than 0.05 mg / m ^2, it is sufficient because the amount of the amino silane coupling agent is too small. The amount of coupling reaction is not performed, and the modification of the polymer particle surface with the amino silane coupling agent becomes insufficient. As a result, the redispersibility is deteriorated. When the content of the amino silane coupling agent adhering per unit surface area of the polymer particle surface is more than 3.0 mg / m ² , the amino silane coupling agent is too much, so the amino type The condensation reaction between the silane coupling agent and water occurs, and the product of the condensation reaction binds the polymer particles to generate aggregation of the polymer particles, so that the dispersibility is impaired.

The content of the amino silane coupling agent in the polymer particle dispersion according to the second aspect of the present invention is 0.05 to 4.0 parts by weight with respect to 100 parts by weight of the polymer particles. More preferably, it is 1 to 3.0 parts by weight. When the content of the amino silane coupling agent in the polymer particle dispersion is less than 0.05 parts by weight, a sufficient amount of coupling reaction is not performed because the amount of the amino silane coupling agent is too small. Further, the modification of the polymer particle surface with the amino silane coupling agent becomes insufficient. As a result, the redispersibility is deteriorated. When the content of the amino silane coupling agent in the polymer particle dispersion is more than 4.0 parts by weight, the amount of the amino silane coupling agent is too large, so the amino silane coupling agent and water The condensation reaction occurs, and the product of the condensation reaction binds the polymer particles to cause aggregation of the polymer particles, so that the dispersibility is impaired.

The volume average particle diameter of the polymer particles is preferably from 0.1 to 30 μm, and more preferably from 0.1 to 5.0 μm. Thereby, when polymer particle dispersion liquid is used for manufacture of optical members, such as an anti-glare film and a light diffusion film, optical characteristics, such as anti-glare property and light diffusibility, of an optical member can be improved. In addition, by setting the volume average particle diameter of the polymer particles to the above upper limit or less, it is possible to realize a polymer particle dispersion liquid in which the polymer particles are less likely to settle and have good redispersibility. In the present application document, the volume average particle diameter of the polymer particles refers to the arithmetic average of the volume-based particle size distribution measured by the Coulter method, for example, the method described in the Examples section.

The coefficient of variation of the volume-based particle diameter of the polymer particles is preferably 20% or less, and more preferably 15% or less. Thereby, a polymer particle dispersion having further improved redispersibility can be realized.

The polymer particles may be obtained by polymerizing in the presence of a surfactant, or may be obtained by adding a surfactant after polymerization. The polymer particles are more preferably obtained by absorbing a vinyl monomer into seed particles and polymerizing the polymer particles (that is, seed polymerization). Since the polymer particles obtained by seed polymerization have little variation in particle diameter, when the polymer particle dispersion is used for the production of an optical member such as an antiglare film or a light diffusing film, Optical properties such as glare and light diffusibility can be improved.

[Method for producing polymer particle dispersion]
In the polymer particle dispersion of the present invention, for example, when the polymer particles are composed of a vinyl monomer polymer, the vinyl monomer is polymerized in the presence of a surfactant in an aqueous medium. It can be manufactured by a method of adding a silane coupling agent later or a method of adding a surfactant after polymerizing a vinyl monomer in an aqueous medium and further adding a silane coupling agent.

When the vinyl monomer is polymerized in the presence of a surfactant, the amount of the surfactant used is in the range of 0.01 to 5 parts by weight with respect to 100 parts by weight of the vinyl monomer. It is preferable that When the amount of the surfactant used is less than the above range, the polymerization stability may be lowered. Moreover, when there is more usage-amount of surfactant than the said range, it is uneconomical in terms of cost.

The polymerization method of the vinyl monomer is not particularly limited as long as it is a known polymerization method using an aqueous medium, and examples thereof include seed polymerization, emulsion polymerization, and suspension polymerization. Of these polymerization methods, seed polymerization is most preferred because the resulting polymer particles have the least variation in particle diameter.

The above-mentioned emulsion polymerization is a method in which an aqueous medium, a vinyl monomer that is difficult to dissolve in this medium, and a surfactant (emulsifier) are mixed, and a polymerization initiator that is soluble in an aqueous medium is added thereto for polymerization. The polymerization method to be performed. The emulsion polymerization is characterized in that there is little variation in the particle diameter of the polymer particles obtained. The suspension polymerization is a polymerization method in which a vinyl monomer and an aqueous medium are mechanically stirred to suspend the vinyl monomer in an aqueous medium for polymerization. The suspension polymerization is characterized in that polymer particles having a small particle size and a relatively uniform particle size can be obtained.

The seed polymerization is a method in which, when starting polymerization of a vinyl monomer, seed (seed) particles made of a polymer of a vinyl monomer prepared separately are put into the polymerization. More specifically, in the seed polymerization, polymer particles made of a vinyl monomer polymer are used as seed particles, the vinyl particles are absorbed in the seed particles in an aqueous medium, This is a method of polymerizing a vinyl monomer. In this method, polymer particles having a larger particle diameter than the original seed particles can be obtained by growing the seed particles. As described above, seed polymerization is the most preferable polymerization method for vinyl monomers.

Hereinafter, a general method of seed polymerization will be described, but the polymerization method is not limited to this method.

In seed polymerization, first, seed particles are added to an emulsion containing a vinyl monomer and an aqueous medium. The emulsion can be prepared by a known method. For example, an emulsion can be obtained by adding a vinyl-based monomer to an aqueous medium and dispersing it with a fine emulsifier such as a homogenizer, an ultrasonic processor, or a nanomizer (registered trademark).

In the seed polymerization, it is preferable to use 0.01 to 5 parts by weight of a surfactant with respect to 100 parts by weight of the vinyl monomer. When the amount of the surfactant used is less than the above range, the polymerization stability may be lowered. Moreover, when there is more usage-amount of surfactant than the said range, it is uneconomical in terms of cost.

The seed particles may be added to the emulsion as it is, or may be added to the emulsion in a form dispersed in an aqueous medium. After the seed particles are added to the emulsion, the vinyl monomer is absorbed by the seed particles. This absorption can usually be performed by stirring the emulsion at room temperature (about 20 ° C.) for 1 to 12 hours. In order to promote the absorption of the vinyl monomer into the seed particles, the emulsion may be heated to about 30 to 50 ° C.

The seed particles swell by absorbing the vinyl monomer. The mixing ratio of the vinyl monomer to the seed particles is preferably within the range of 5 to 300 parts by weight of the vinyl monomer and 1 to 50 parts by weight with respect to 1 part by weight of the seed particles. More preferably, it is within. When the mixing ratio of the vinyl monomer is smaller than the above range, the increase in particle diameter due to polymerization is small, and thus the production efficiency is lowered. On the other hand, when the mixing ratio of the vinyl monomer is larger than the above range, the vinyl monomer is not completely absorbed by the seed particles, and it is uniquely emulsion-polymerized in an aqueous medium, resulting in an abnormal particle size that is not intended. Of polymer particles may be produced. In addition, the completion | finish of absorption of the vinyl-type monomer to a seed particle can be determined by confirming expansion of a particle diameter by observation with an optical microscope.

Next, a polymer particle dispersion is obtained by polymerizing the vinyl monomer absorbed by the seed particles. In addition, you may obtain a polymer particle dispersion by repeating the process of making a seed particle absorb and polymerize a vinyl-type monomer in multiple times.

A polymerization initiator may be added to the vinyl monomer as necessary. The polymerization initiator may be obtained by mixing the polymerization initiator with the vinyl monomer, and then dispersing the obtained mixture in an aqueous medium, or combining both the polymerization initiator and the vinyl monomer. Those separately dispersed in an aqueous medium may be mixed. The particle size of the vinyl monomer droplets present in the resulting emulsion is preferably smaller than the particle size of the seed particles because the vinyl monomer is efficiently absorbed by the seed particles.

The polymerization initiator is not particularly limited. For example, benzoyl peroxide, lauroyl peroxide, benzoyl peroxide, o-methoxybenzoyl peroxide, 3,5,5-trimethylhexanoyl peroxide Organic peroxides such as oxide, t-butylperoxy-2-ethylhexanoate, di-tert-butyl peroxide; 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) 3-trimethylbutyronitrile), 2,2′-azobis (2-isopropylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonite) ), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), (2-carbamoylazo) isobutyronitrile, 4,4′-azobis (4-cyanovaleric acid), dimethyl-2 Azo compounds such as 2,2′-azobisisobutyrate. The polymerization initiator is preferably used within a range of 0.1 to 1.0 part by weight with respect to 100 parts by weight of the vinyl monomer.

The polymerization temperature of the seed polymerization can be appropriately selected according to the type of vinyl monomer and the type of polymerization initiator used as necessary. Specifically, the polymerization temperature of the seed polymerization is preferably 25 to 110 ° C., and more preferably 50 to 100 ° C. The polymerization time for the seed polymerization is preferably 1 to 12 hours. The polymerization reaction of the seed polymerization may be performed in an atmosphere of an inert gas (for example, nitrogen) that is inert to the polymerization. The seed polymerization is preferably carried out by raising the temperature after the vinyl monomer and the polymerization initiator used as necessary are completely absorbed by the seed particles.

In the seed polymerization, a polymer dispersion stabilizer may be added to the polymerization reaction system in order to improve the dispersion stability of the polymer particles. Examples of the polymer dispersion stabilizer include polyvinyl alcohol, polycarboxylic acid, celluloses (such as hydroxyethyl cellulose and carboxymethyl cellulose), and polyvinylpyrrolidone. Moreover, the polymer dispersion stabilizer and an inorganic water-soluble polymer compound such as sodium tripolyphosphate may be used in combination. Of these polymer dispersion stabilizers, polyvinyl alcohol and polyvinyl pyrrolidone are preferred. The addition amount of the polymer dispersion stabilizer is preferably in the range of 1 to 10 parts by weight with respect to 100 parts by weight of the vinyl monomer.

In order to suppress the occurrence of emulsion polymerization products (polymer particles having a particle size too small) in the aqueous medium in the polymerization reaction, nitrites such as sodium nitrite, sulfites, hydroquinones, ascorbic acids, Water-soluble polymerization inhibitors such as water-soluble vitamin Bs, citric acid, and polyphenols may be added to the aqueous medium. The addition amount of the polymerization inhibitor is preferably in the range of 0.02 to 0.2 parts by weight with respect to 100 parts by weight of the vinyl monomer.

The polymerization method for obtaining seed particles by polymerizing a vinyl monomer is not particularly limited, but dispersion polymerization, emulsion polymerization, soap-free emulsion polymerization (emulsion polymerization without using a surfactant as an emulsifier). , Seed polymerization, suspension polymerization and the like can be used. In order to obtain polymer particles having a substantially uniform particle size by seed polymerization, it is necessary to first use seed particles having a substantially uniform particle size and grow these seed particles substantially uniformly. Seed particles having a substantially uniform particle size as a raw material can be produced by polymerizing a vinyl monomer by a polymerization method such as soap-free emulsion polymerization (emulsion polymerization without using a surfactant) and dispersion polymerization. Accordingly, emulsion polymerization, soap-free emulsion polymerization, seed polymerization, and dispersion polymerization are preferred as polymerization methods for polymerizing vinyl monomers to obtain seed particles.

Also in the polymerization for obtaining seed particles, a polymerization initiator is used as necessary. Examples of the polymerization initiator include persulfates such as potassium persulfate, ammonium persulfate, sodium persulfate; benzoyl peroxide, lauroyl peroxide, o-chlorobenzoyl peroxide, o-methoxybenzoyl peroxide, 3, 5 , 5-trimethylhexanoyl peroxide, tert-butylperoxy-2-ethylhexanoate, organic peroxides such as di-tert-butyl peroxide; 2,2′-azobisisobutyronitrile, Examples thereof include azo compounds such as 1′-azobiscyclohexanecarbonitrile and 2,2′-azobis (2,4-dimethylvaleronitrile). The amount of the polymerization initiator used is preferably in the range of 0.1 to 3 parts by weight with respect to 100 parts by weight of the vinyl monomer used to obtain seed particles. The weight average molecular weight of the seed particles obtained can be adjusted by adjusting the amount of the polymerization initiator used.

In the polymerization for obtaining seed particles, a molecular weight modifier may be used in order to adjust the weight average molecular weight of the obtained seed particles. Examples of the molecular weight modifier include mercaptans such as n-octyl mercaptan and tert-dodecyl mercaptan; α-methylstyrene dimer; terpenes such as γ-terpinene and dipentene; halogenated hydrocarbons such as chloroform and carbon tetrachloride, etc. Can be used. The weight average molecular weight of the seed particles obtained can be adjusted by adjusting the amount of the molecular weight modifier used.

[Dispersant]
The dispersant of the present invention includes a reaction product of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent. The surfactant and the amino silane coupling agent are the same as the surfactant and amino silane coupling agent in the polymer particle dispersion according to the first and second aspects of the present invention.

The dispersant of the present invention comprises a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent in the presence of a medium such as water or a polar organic solvent, or It can manufacture by mixing and making it react in absence. Although reaction conditions are not specifically limited, For example, reaction temperature can be 30 degreeC and reaction time can be 1 hour.

The dispersant of the present invention disperses solid particles such as inorganic pigments, organic pigments, resin particles, and oil agents such as fats and oils, waxes, hydrocarbons, higher fatty acids, higher alcohols, sterols, and fatty acid esters in a dispersion medium. It can be used as a dispersing agent.

White inorganic pigments such as lead white, zinc oxide and titanium dioxide; yellow inorganic pigments such as yellow lead, titanium yellow and Navels yellow; orange inorganic pigments such as molybdenum orange; red such as red lead and iron oxide Inorganic pigments; blue inorganic pigments such as ultramarine and cobalt oxide; black inorganic pigments such as carbon black and titanium black;

Examples of the organic pigments include yellow organic pigments such as naphthol yellow S, hansa yellow 10G, benzidine yellow G, benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, tartrazine lake; permanent orange RK, benzidine orange GR, indanthrene brilliant. Orange organic pigments such as orange GK; red organic pigments such as permanent red 4R, resol red, pyrazolone red, watching red calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, alizarin lake, brilliant carmine BS; Purple organic pigments such as Fast Violet B, Methyl Violet Lake, Dioxane Violet; Alkaline Blue Lake, Victoria Blue Lake Blue organic pigments such as phthalocyanine blue, metal-free phthalocyanine blue, phthalocyanine blue partial chloride, fast sky blue and indanthrene blue BC; green organic pigments such as Pigment Green B, Malachite Green Lake, and Fanal Yellow Green G Is mentioned. Examples of the organic pigment include isoindolinone pigment, quinacridone pigment, perinone pigment, perylene pigment, insoluble azo pigment, soluble azo pigment, and dyed lake pigment.

The dispersant of the present invention includes (meth) acrylic polymer particles, styrene polymer particles, (meth) acrylic-styrene copolymer particles, vinyl ester polymer particles, polyurethane polymer particles, polyethylene terephthalate. Particularly suitable as a dispersant for dispersing at least one solid particle selected from the group consisting of polymer polymer particles, silicone polymer particles, and fluorine resin particles.
Further, the dispersant of the present invention exhibits a great effect when the average particle size of the solid particles is 0.1 to 50 μm, particularly 0.1 to 30 μm.

The dispersant of the present invention is, for example, for the purpose of homogenizing the dispersion of polymer particles when preparing a polymer particle dispersion by dispersing polymer particles in at least one dispersion medium of water and a polar organic solvent. Can be added to the dispersion medium. The dispersant of the present invention can be added to the reaction system for the purpose of stabilizing the dispersion without agglomerating the polymer particles during a polymerization reaction such as suspension polymerization, emulsion polymerization, dispersion polymerization, or seed polymerization.

[Dispersion medium]
The dispersion medium of the present invention contains at least one of water and a polar organic solvent and the dispersant of the present invention.

The dispersion medium of the present invention is a reaction in which a surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety and an amino silane coupling agent are mixed in the presence of at least one of water and a polar organic solvent. It can also be produced by dispersing the dispersant of the present invention in at least one of water and a polar organic solvent. Although the reaction conditions in the former production method are not particularly limited, for example, the reaction temperature may be 30 ° C. and the reaction time may be 1 hour.

Specific examples of the polar organic solvent include isopropyl alcohol, methyl alcohol, and ethyl alcohol.

The dispersion medium of the present invention is used, for example, for the purpose of preparing a polymer particle dispersion by uniformly dispersing polymer particles, or for polymer particles during a polymerization reaction such as suspension polymerization, emulsion polymerization, dispersion polymerization, or seed polymerization. It can be used for the purpose of stabilizing the dispersion without agglomeration.

(Polymer particle dispersion)
The polymer particle dispersion according to the third aspect of the present invention is a dispersion of polymer particles in the dispersion medium of the present invention. The polymer particles are the same as the polymer particles in the polymer particle dispersion according to the first and second aspects of the present invention.

[Polymer particles and production method thereof]
In the polymer particle of the present invention, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent are attached to the surface of the polymer particle. The content of the surfactant attached per unit surface area of the particle surface is 0.6 to 15.0 mg / m ² , and the amino group attached per unit surface area of the polymer particle surface The content of the silane coupling agent is 0.05 to 3.0 mg / m ² .

The polymer particles of the present invention are obtained by drying the polymer particle dispersion according to the first aspect of the present invention to obtain polymer particle aggregates, and then dispersing the obtained polymer particle aggregates in primary particles. It can be manufactured by the method. As the drying method, for example, spray drying can be used. As a method of dispersing the polymer particle aggregates in the primary particles, a method of pulverizing and dispersing the polymer particle aggregates with an airflow pulverizer can be used.

[Use of polymer particle dispersion]
The polymer particle dispersion according to any one of the first to third aspects of the present invention and the polymer particles of the present invention can be used as a coating agent, an antiblocking agent, a pore forming agent and the like.

[Anti-blocking agent]
The polymer particle dispersion according to any one of the first to third aspects of the present invention and the polymer particles of the present invention peel off when the resin film surfaces in contact with each other are in close contact with each other when the resin film is wound up. In order to prevent disappearance (blocking), it can be used as an anti-blocking agent that imparts irregularities to the surface of the resin film.

Examples of the resin film include polyester resins such as polyethylene terephthalate and polyethylene naphthalate; polyolefin resins such as polyethylene resins and polypropylene resins; (meth) acrylic resins, polystyrene resins, polyethersulfone resins, and polyurethanes. Resin, polycarbonate resin, polysulfone resin, polyether resin, polymethylpentene resin, polyether ketone resin, (meth) acrylonitrile resin, norbornene resin, amorphous polyolefin resin, polyamide resin, polyimide Examples of the resin film include a resin and a resin such as a triacetyl cellulose resin.

[Pore former]
The polymer particle dispersion according to any one of the first to third aspects of the present invention and the polymer particles of the present invention can be used as a pore-forming agent for forming pores when producing a ceramic porous body. The ceramic raw materials for producing the ceramic porous body include kaolin, talc, alumina, zirconia, magnesia, silica, mullite, cordierite, silicon carbide, silicon nitride, clay, mica, porcelain stone, feldspar, silica stone, lime carbonate, etc. Is mentioned.

The method for producing the ceramic porous body is not particularly limited, and any known method can be used. For example, a polymer particle dispersion containing 5 to 100 parts by weight of polymer particles is added to 100 parts by weight of a ceramic raw material, or 5 to 100 parts by weight of polymer particles and a medium such as water are added and then kneaded. And dredged. This clay is molded by pressing into a desired shape, then dried, degreased by holding at 400 to 600 ° C. for 1 to 5 hours, and then fired at 1000 to 2200 ° C. for 1 to 5 hours. A ceramic porous body can be produced.

〔Coating agent〕
The coating agent of the present invention contains the polymer particle dispersion according to any one of the first to third aspects of the present invention or the polymer particles of the present invention and a binder. The coating agent of this invention can be used conveniently for manufacture of an optical film.

The binder is not particularly limited as long as it is used in the field according to required properties such as transparency, polymer particle dispersibility, light resistance, moisture resistance and heat resistance. Examples of the binder 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; silicone resin such as alkylpolysiloxane resin; (meth) acrylic-silicone resin, silicone-alkyd resin, silicone-urethane resin, silicone-polyester resin, etc. Modified silicone resins; binder resins such as fluororesins such as polyvinylidene fluoride and fluoroolefin vinyl ether polymers.

The binder resin is preferably a curable resin capable of forming a crosslinked structure by a crosslinking reaction from the viewpoint of improving the durability of the coating resin composition. The curable resin can be cured under various curing conditions. The curable resin is classified into an ionizing radiation curable resin such as an ultraviolet curable resin and an electron beam curable resin, a thermosetting resin, a hot air curable resin, and the like depending on the type of curing.

Examples of the thermosetting resin include thermosetting urethane resin composed of acrylic polyol and isocyanate prepolymer, phenol resin, urea melamine resin, epoxy resin, unsaturated polyester resin, and silicone resin.

As the ionizing radiation curable resin, synthesized from polyfunctional (meth) acrylate resin such as polyhydric alcohol polyfunctional (meth) acrylate; diisocyanate, polyhydric alcohol, and (meth) acrylic acid ester having a hydroxy group And polyfunctional urethane acrylate resins. The ionizing radiation curable resin is preferably a polyfunctional (meth) acrylate resin, and more preferably a polyhydric alcohol polyfunctional (meth) acrylate having three or more (meth) acryloyl groups in one molecule. As polyhydric alcohol polyfunctional (meth) acrylate having 3 or more (meth) acryloyl groups in one molecule, specifically, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, 1,2,4-cyclohexane tri (meth) acrylate, pentaglycerol triacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetra (Meth) acrylate, dipentaerythritol hexa (meth) acrylate, tripentaerythritol triacrylate, tripentaerythritol hexaacrylate, etc. . Two or more kinds of the ionizing radiation curable resins may be used in combination.

As the ionizing radiation curable resin, besides these, polyether resins having an acrylate functional group, polyester resins, epoxy resins, alkyd resins, spiroacetal resins, polybutadiene resins, polythiol polyene resins, and the like can also be used.

When using an ultraviolet curable resin among the above ionizing radiation curable resins, a photopolymerization initiator is added to the ultraviolet curable resin to form a binder. Although what kind of thing may be used for the said photoinitiator, it is preferable to use what was suitable for the ultraviolet curable resin to be used.

Examples of the photopolymerization initiator include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, α-hydroxyalkylphenones, α-aminoalkylphenones, anthraquinones, thioxanthones, azo compounds, peroxides (Described in JP-A No. 2001-139663), 2,3-dialkyldione compounds, disulfide compounds, fluoroamine compounds, aromatic sulfoniums, onium salts, borate salts, active halogen compounds, α-acyloximes Examples include esters.

Examples of the acetophenones include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, 1-hydroxydimethylphenyl ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-4-methylthio-2-morpholinopropio. Examples include phenone and 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone. Examples of the benzoins include benzoin, benzoin benzoate, benzoin benzene sulfonate, benzoin toluene sulfonate, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether. Examples of the benzophenones include benzophenone, 2,4-dichlorobenzophenone, 4,4'-dichlorobenzophenone, p-chlorobenzophenone, and the like. Examples of the phosphine oxides include 2,4,6-trimethylbenzoyldiphenylphosphine oxide. Examples of the ketals include benzylmethyl ketals such as 2,2-dimethoxy-1,2-diphenylethane-1-one. Examples of the α-hydroxyalkylphenones include 1-hydroxycyclohexyl phenyl ketone. Examples of the α-aminoalkylphenones include 2-methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) -1-propanone.

Commercially available radical photopolymerization initiators include trade names “Irgacure (registered trademark) 651” (2,2-dimethoxy-1,2-diphenylethane-1-one) manufactured by BASF Japan Ltd., manufactured by BASF Japan Ltd. Trade name “Irgacure (registered trademark) 184”, and trade name “Irgacure (registered trademark) 907” (2-methyl-1- [4- (methylthio) phenyl] -2- (4-morpholinyl) manufactured by BASF Japan Ltd. ) -1-propanone) and the like.

The amount of the photopolymerization initiator used is usually in the range of 0.5 to 20% by weight, preferably in the range of 1 to 5% by weight with respect to 100% by weight of the binder.

As the binder resin, a thermoplastic resin can be used in addition to the curable resin. Examples of the thermoplastic resin include cellulose derivatives such as acetylcellulose, nitrocellulose, acetylbutylcellulose, ethylcellulose, and methylcellulose; homopolymers and copolymers of vinyl acetate, homopolymers and copolymers of vinyl chloride, and vinylidene chloride. Vinyl resins such as homopolymers and copolymers; acetal resins such as polyvinyl formal and polyvinyl butyral; homopolymers and copolymers of acrylate esters, homopolymers and copolymers of methacrylate esters, etc. ) Acrylic resin; polystyrene resin; polyamide resin; linear polyester resin; polycarbonate resin.

In addition to the binder resin, a rubber binder such as synthetic rubber or natural rubber, an inorganic binder, or the like can be used as the binder. Examples of the rubber binder resin include ethylene-propylene copolymer rubber, polybutadiene rubber, styrene-butadiene rubber, and acrylonitrile-butadiene rubber. These rubber-based binder resins may be used alone or in combination of two or more.

Examples of the inorganic binder include silica sol, alkali silicate, silicon alkoxide, and phosphate. As the inorganic binder, an inorganic or organic-inorganic composite matrix obtained by hydrolysis and dehydration condensation of metal alkoxide or silicon alkoxide can also be used. As the inorganic or organic-inorganic composite matrix, a silicon oxide matrix obtained by hydrolysis and dehydration condensation of a silicon alkoxide such as tetraethoxysilane can be used. These inorganic binders may be used alone or in combination of two or more.

The amount of the polymer particles in the coating agent is preferably 2 parts by weight or more, more preferably 4 parts by weight or more, and 6 parts by weight or more with respect to 100 parts by weight of the solid content of the binder. More preferably. By making the amount of the polymer particles 2 parts by weight or more with respect to 100 parts by weight of the solid content of the binder, it becomes easy to make the matte property of the coating (coating film) formed by the coating agent sufficient. Therefore, for example, when an optical film is produced by applying a coating agent on a film substrate, the optical properties such as antiglare property and light diffusibility of the optical film can be easily obtained. The amount of the polymer particles in the coating agent is preferably 300 parts by weight or less, more preferably 200 parts by weight or less, and 100 parts by weight or less with respect to 100 parts by weight of the solid content of the binder. More preferably. By making the amount of the polymer particles 300 parts by weight or less with respect to 100 parts by weight of the solid content of the binder, it becomes easy to make the linear permeability of the coating formed by the coating agent sufficient.

The coating agent may contain an organic solvent in addition to the polymer particle dispersion or the polymer particles and the binder. The organic solvent is not particularly limited as long as it can be easily applied to the base material by containing it in the coating agent. Examples of the organic solvent include aromatic solvents such as toluene and xylene; alcohol solvents such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, and propylene glycol monomethyl ether; Ester solvents such as ethyl acetate and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone; 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, ethylene glycol dimethyl ether, ethylene Glycol ethers such as glycol diethyl ether, diethylene glycol dimethyl ether, and propylene glycol methyl ether; 2-methoxyethyl acetate Salts, glycol ether esters such as 2-ethoxyethyl acetate (cellosolve acetate), 2-butoxyethyl acetate, propylene glycol methyl ether acetate; chlorinated solvents such as chloroform, dichloromethane, trichloromethane, and methylene chloride Ether solvents such as tetrahydrofuran, diethyl ether, 1,4-dioxane and 1,3-dioxolane; amide solvents such as N-methylpyrrolidone, dimethylformamide, dimethyl sulfoxide and dimethylacetamide can be used. These organic solvents may be used alone or in combination of two or more.

[Use of polymer particles]
The polymer particles of the present invention are suitable for optical films such as antiglare films and light diffusion films, and optical members such as light diffusers, and particularly suitable for antiglare members.

[Optical film]
The optical film of the present invention includes a film substrate and a coating formed on the film, and the coating includes the polymer particles of the present invention and a binder. The optical film of the present invention can be produced by applying the coating agent of the present invention on a film substrate and drying it.

The film substrate is preferably transparent. Examples of transparent film base materials include polyester polymers such as polyethylene terephthalate (PET) and polyethylene naphthalate, cellulose polymers such as diacetyl cellulose and triacetyl cellulose (TAC), polycarbonate polymers, and polymethyl methacrylate. And a film made of a polymer such as a (meth) acrylic polymer. In addition, as a transparent film base material, polystyrene, styrene polymer such as acrylonitrile / styrene copolymer, polyethylene, polypropylene, polyolefin having cyclic or norbornene structure, olefin polymer such as ethylene / propylene copolymer, chloride A film made of a polymer such as a vinyl polymer or an amide polymer such as nylon or aromatic polyamide may also be mentioned. Further, as transparent film base materials, imide polymers, sulfone polymers, polyether sulfone polymers, polyether ether ketone polymers, polyphenyl sulfide polymers, vinyl alcohol polymers, vinylidene chloride. Examples thereof include films made of polymers such as polymers, vinyl butyral polymers, arylate polymers, polyoxymethylene polymers, epoxy polymers and blends of the above polymers. As the film substrate, those having a particularly low birefringence are preferably used. Further, a film in which an easy-adhesion layer such as (meth) acrylic resin, copolymerized polyester resin, polyurethane resin, styrene-maleic acid grafted polyester resin, acrylic grafted polyester resin, etc. is further provided on these films is also used as the film substrate. Can be used.

The thickness of the film substrate can be determined as appropriate, but is generally within the range of 10 to 500 μm and within the range of 20 to 300 μm from the viewpoints of strength, workability such as handling, and thin layer properties. It is preferable that it is within a range of 30 to 200 μm.

In addition, an additive may be added to the film substrate. Examples of the additive include an ultraviolet absorber, an infrared absorber, an antistatic agent, a refractive index adjuster, and an enhancer.

As a method of applying the coating agent on the film substrate, bar coating, blade coating, spin coating, reverse coating, die coating, spray coating, roll coating, gravure coating, micro gravure coating, lip coating, air knife coating, A known coating method such as a dipping method may be used.

When the binder contained in the coating agent is an ionizing radiation curable resin, the ionizing radiation curable resin is dried by applying an active energy ray after the aqueous agent or organic solvent is dried as necessary after the coating agent is applied. Can be cured.

Examples of the active energy rays include ultraviolet rays emitted from light sources such as xenon lamps, low-pressure mercury lamps, high-pressure mercury lamps, ultra-high pressure mercury lamps, metal halide lamps, carbon arc lamps, tungsten lamps, etc .; Electron beams, α rays, β rays, γ rays and the like extracted from electron beam accelerators such as a type, a resonant transformation type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type can be used.

The thickness of the coating formed by application (and curing) of the coating agent is not particularly limited and is appropriately determined depending on the particle diameter of the polymer particles, but is preferably in the range of 1 to 10 μm. More preferably, it is in the range of 7 μm.

The optical film of the present invention described above can be suitably used for light diffusion or antiglare, that is, as a light diffusion film or antiglare film.

Hereinafter, although an example and a comparative example explain the present invention, the present invention is not limited to this. Before explaining the examples and comparative examples, each evaluation of the polymer particle dispersions in the examples and comparative examples (measurement of solid content concentration, volume average particle diameter of polymer particles and variation in volume-based particle diameter) Measurement of coefficient, measurement of surfactant coating amount of polymer particles, measurement of surfactant content of polymer particles, measurement of specific surface area of polymer particles, measurement of silane coupling agent content of polymer particles, Evaluation of redispersibility after sedimentation and evaluation of redispersibility after powder reslurry), adjustment method of solid content concentration of polymer particle dispersion, and measurement method of volume average particle diameter of seed particles This will be described below.

[Method for measuring the concentration of solid content (polymer particles) of polymer particle dispersion]
10 g of the polymer particle dispersion is weighed into a pre-weighed measuring vessel and dried in an oven at 70 ° C. for 10 hours to recover the evaporated dry matter. The weight of the measurement container containing the recovered evaporated dry solid (solid content) (= the weight of the measurement container + the weight of the evaporated dry solid) is measured. From the weight of the measurement container and the weight of the measurement container containing the evaporated and dried product, the concentration [wt%] of the solid content of the polymer particle dispersion (stock solution) is calculated by the following formula.
Concentration of solid content of polymer particle dispersion [wt%]
= {Weight of measuring container containing evaporated dry matter-Weight of measuring container}
÷ Weight of polymer particle dispersion (10 g)} × 100

[Method of adjusting the solid content concentration of the polymer particle dispersion]
In the silane coupling treatment steps of the following examples and comparative examples, when the solid content concentration of the polymer particle dispersion obtained in the polymerization step is higher than the desired solid content concentration, By adding a dispersion medium, the solid content concentration of the polymer particle dispersion is adjusted to a desired solid content concentration. In the measurement of the surfactant content and the measurement of the silane coupling agent content, which will be described later, since a polymer particle dispersion having a solid content of 20% by weight is used, it is obtained in Examples and Comparative Examples. When the solid content concentration of the polymer particle dispersion liquid is higher than 20% by weight, the solid content concentration of the polymer particle dispersion liquid is adjusted to 20% by weight by adding a dispersion medium to the polymer particle dispersion liquid. Then, the surfactant content and the silane coupling agent content are measured.

The amount of the dispersion medium added to adjust the concentration of the solid content of the polymer particle dispersion is determined by the weight of the polymer particle dispersion (before the addition of the dispersion medium) and the polymer particle dispersion (before the addition of the dispersion medium). It can be calculated by the following formula from the solid content concentration of the liquid and the desired solid content concentration.
Addition amount of dispersion medium = {(weight of polymer particle dispersion × concentration of solid content of polymer particle dispersion)
/ Concentration of desired solid content}
-Weight of polymer particle dispersion

In the silane coupling treatment steps of the following examples and comparative examples, when the solid content concentration of the polymer particle dispersion obtained in the polymerization step is lower than the desired solid content concentration, it is concentrated by an ultrafiltration device. By doing so, the solid content concentration of the polymer particle dispersion is adjusted to a desired solid content concentration. In the measurement of the surfactant content and the measurement of the silane coupling agent content, which will be described later, since a polymer particle dispersion having a solid content of 20% by weight is used, it is obtained in Examples and Comparative Examples. When the solid content concentration of the polymer particle dispersion liquid is lower than 20% by weight, the solid content concentration of the polymer particle dispersion liquid is adjusted to a predetermined concentration by concentrating with an ultrafiltration device. The surfactant content and the silane coupling agent content are measured.

[Measurement method of coefficient of variation of volume average particle diameter and volume-based particle diameter of polymer particles]
The volume average particle diameter of the polymer particles is measured using a laser diffraction / scattering particle size distribution measuring device (“LS 13 320” manufactured by Beckman Coulter, Inc.) and a universal liquid sample module.

Specifically, 0.1 g of the polymer particle dispersion is added to 10 ml of a 0.1% by weight nonionic surfactant aqueous solution by touch mixer (manufactured by Yamato Kagaku Co., Ltd., “TOUCHMIXER MT-31”) and ultrasonic cleaner ( Dispersed using “ULTRASONIC CLEANER VS-150” manufactured by VervoCrea Co., Ltd., and used as a dispersion.

The volume-based particle size distribution of the polymer particles is measured in a state where the polymer particles are dispersed by performing pump circulation in the universal liquid sample module and the ultrasonic unit (ULM ULTRASONIC MODULE) is activated. From the volume-based particle size distribution, the volume average particle diameter of the polymer particles (the arithmetic average diameter in the volume-based particle size distribution) is calculated. The measurement conditions are shown below.

Medium = Water Refractive index of medium = 1.333
Refractive index of solid = refractive index of polymer particles (when polymer particles are polymethyl methacrylate particles, 1.495)
PIDS relative concentration: about 40-55%

The variation coefficient (CV value) of the volume-based particle diameter of the polymer particles is calculated by the following mathematical formula.
Variation coefficient of volume-based particle diameter of polymer particles = (standard deviation of volume-based particle size distribution of polymer particles ÷ volume average particle diameter of polymer particles)
× 100

[Method for measuring volume average particle diameter of seed particles]
The volume average particle size of the seed particles is measured in the same manner as the measurement of the volume average particle size of the polymer particles in the polymer particle dispersion, except that a seed particle slurry is used instead of the polymer particle dispersion. To do.

[Measurement Method of Polymer Particle Surfactant Coating Amount (Content of Surfactant Adhering Per Unit Surface Area of Polymer Particle Surface)]
For the polymer particle dispersion, the surfactant content A [μg / g] and specific surface area B [m ² / g] per 1 g of polymer particles are measured by the method described later, and the interface is calculated from A and B according to the following formula. The surfactant coating amount [μg / m ² ] is calculated, and this is converted into mg / m ² unit (multiplied by 10 ³ ) to calculate the surfactant coating amount [mg / m ² ].
Surfactant coating amount = A / B

[Method for measuring surfactant content of polymer particles]
The surfactant content per 1 g of the polymer particles is measured using a liquid chromatograph mass spectrometer (LC / MS / MS apparatus) after extracting the recovered polymer particle powder with a solvent.

In addition, for the measurement of the content of the surfactant in the polymer particles of Examples and Comparative Examples described later, as a LC / MS / MS apparatus, “UHPLC ACCELA” manufactured by Thermo Fisher Scientific and “manufactured by Thermo Fisher Scientific” "Linear Ion Trap LC / MS ⁿ LXQ" was used.

In addition, polymer particles in Examples and Comparative Examples to be described later are polyoxyethylene nonylphenyl ether phosphate, polyoxyethylene distearate, di (2-ethylhexyl) sulfosuccinate, and dodecylbenzene as surfactants. At least one sulfonate was used, and the surfactant content in the polymer particles of Examples and Comparative Examples was measured by the following method.

20 g of polymer particle dispersion liquid having a solid content adjusted to 20% by weight is placed in a centrifuge tube having an inner diameter of 24 mm and subjected to solid-liquid separation using a centrifuge. As a result, the supernatant liquid containing the surfactant not adhering to the polymer particle surface and the silane coupling agent not adhering to the polymer particle surface is removed, and an amount of ion-exchanged water corresponding to the removed amount is newly added. It put into the centrifuge tube and re-dispersed using the ultrasonic disperser, using instruments, such as a medicine spoon, suitably. Thereafter, solid-liquid separation was performed again using a centrifuge, and the supernatant was removed. This process was repeated once more and the supernatant was removed in the same procedure. The sediment after removing the supernatant was collected and dried in an oven at 80 ° C. for 10 hours to obtain a dry powder.

Into a test tube, 0.50 g of a dry powder of polymer particles obtained by drying and 5 ml of methanol are added, 50 μL of a 1000 ppm concentration of pyrene in methanol as an internal standard is added, and the silane coupling agent is further released. 0.5 ml of an aqueous hydrochloric acid solution (concentration 20% by weight) was added. Thereafter, by treating with an ultrasonic disperser for 20 minutes, the surfactant and the silane coupling agent are extracted into methanol, and solid-liquid separation is performed using a centrifuge. The supernatant obtained by solid-liquid separation was collected and filtered through a non-aqueous 0.45 μm chromatodisc to prepare a test solution.

Measure the surfactant concentration in the test solution using an LC / MS / MS apparatus. The measured surfactant concentration [μg / ml] in the test solution, the weight of the polymer particle powder used as the sample (sample weight [g]), and the amount of the extract (extract solution amount [ml] ]), The surfactant content [μg / g] per 1 g of polymer particles and the surfactant content [wt%] in the polymer particles are determined by the following calculation formula. The amount of the extract is 5 ml.

Surfactant content [μg / g]
= {Surfactant concentration in test solution [μg / ml] x amount of extract [ml]}
÷ Sample weight [g]
Surfactant content [wt%]
= 100 × 10 ⁻⁶ ×
{Surfactant concentration in test solution [μg / ml] x extract volume [ml]}
÷ Sample weight [g]

The surfactant concentration is calculated from a peak area value on the obtained chromatogram using a calibration curve prepared in advance from a surfactant stock solution using an LC / MS / MS apparatus. Further, when the polymer particles contain a plurality of types of surfactants, for each of these surfactants, create a calibration curve, calculate the surfactant concentration using the created calibration curve, and calculate each The total surfactant concentration of the surfactant is determined as the “surfactant concentration in the test solution [μg / ml]” in the above calculation formula to determine the surfactant content of the polymer particles.

-LC measurement conditions-
Measuring apparatus: UHPLC ACCELA (manufactured by Thermo Fisher Scientific)
Column: Hypersil GOLD C18 1.9 μm (inner diameter 2.1 mm, length 100 mm) manufactured by Thermo Fisher Scientific

-MS measurement conditions-
Measuring device: Linear Ion Trap LC / MS ⁿ LXQ (manufactured by Thermo Fisher Scientific)
Ionization: (ESI / negative)
Sheath gas: 30 arb
Auxiliary gas (AUX Gas): 10arb
Sweep Gas: 0arb
Spray voltage (I Spray Voltage): 5.0 kV
Capillary temperature: 350 ° C.
Capillary voltage: -20V
Tube lens voltage: -100V

[Method for measuring specific surface area of polymer particles]
The polymer particle dispersion is spray-dried with a spray dryer (for example, manufacturer: Sakamoto Giken Co., Ltd., model: atomizer method and take-up type, model: TRS-3WK spray dryer), and collected as a polymer particle aggregate. . Thereafter, the collected polymer particle aggregate is made into primary particles with an airflow crusher (for example, “Current Jet (registered trademark)” of Nissin Engineering Co., Ltd., “Super Jet Mill” of Nisshin Engineering Co., Ltd., etc.) The obtained polymer particle powder is recovered by pulverization and dispersion.

The spray drying conditions were as follows: polymer particle dispersion feed rate: 20 ml / min, atomizer speed: 13000 rpm, air volume: 2.0 m ³ / min, inlet temperature (inlet where polymer particle dispersion was introduced into the machine) Temperature): 150 ° C., outlet temperature (temperature of outlet at which polymer particles are discharged as a powder (polymer particle aggregate)): 70 ° C. The conditions for pulverization and dispersion are as follows: polymer particle aggregate supply rate: 10 to 20 g / min; pulverization pressure: 0.40 to 0.60 MPa.

The specific surface area of the polymer particles is measured by the BET method (nitrogen adsorption method) described in ISO 9277 1st edition JIS Z 8830: 2001. About the collected polymer particle powder, the BET nitrogen adsorption isotherm was measured using an automatic specific surface area / pore distribution measuring device Tristar 3000 manufactured by Shimadzu Corporation, and the ratio of the nitrogen adsorption amount was measured using the BET multipoint method. Calculate the surface area. After performing the pretreatment by the heated gas purge, measurement is performed using the constant volume method under the condition of the adsorbate cross-sectional area of 0.162 nm ² using nitrogen as the adsorbate. Specifically, in the pretreatment, the container containing the recovered polymer particle powder was heated at 65 ° C., purged with nitrogen for 20 minutes, allowed to cool to room temperature, and then cooled to 65 ° C. While heating, vacuum deaeration is performed until the pressure in the container becomes 0.05 mmHg or less.

[Measurement method of silane coupling agent modification amount of polymer particles (content of silane coupling agent adhered per unit surface area of polymer particle surface)]
The silane coupling agent modification amount C [μg / g] per 1 g of polymer particles is measured by the method described later, the specific surface area B [m ² / g] is measured by the above-described method, and the following formula is obtained from C and B by the following formula. The amount of silane coupling agent modification [μg / m ² ] is calculated, and this is converted into mg / m ² units (multiplied by 10 ³ ) to calculate the amount of silane coupling agent modification [mg / m ² ].
Silane coupling agent modification amount = C / B

[Measurement method of silane coupling agent content of polymer particles]
The silane coupling agent content of the polymer particles was measured with a gas chromatograph mass spectrometer (GC / MS) apparatus (“JMS-Q1000GC” manufactured by JEOL Ltd.).

In addition, polymer particles in Examples and Comparative Examples described later have, as silane coupling agents, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropylmethyldimethoxysilane, and At least one of vinyltrimethoxysilane was used, and the content of the silane coupling agent in the polymer particles of Examples and Comparative Examples was measured by the following method.

20 g of polymer particle dispersion liquid having a solid content adjusted to 20% by weight is placed in a centrifuge tube having an inner diameter of 24 mm and subjected to solid-liquid separation using a centrifuge. As a result, the supernatant liquid containing the surfactant not adhering to the polymer particle surface and the silane coupling agent not adhering to the polymer particle surface is removed, and an amount of ion-exchanged water corresponding to the removed amount is newly added. It put into the centrifuge tube and re-dispersed using the ultrasonic disperser, using instruments, such as a medicine spoon, suitably. Thereafter, solid-liquid separation was performed again using a centrifuge, and the supernatant was removed. This process was repeated once more and the supernatant was removed in the same procedure. The sediment after removing the supernatant was collected and dried in an oven at 80 ° C. for 10 hours to obtain a dry powder.

Into a test tube, 0.50 g of a dry powder of polymer particles obtained by drying and 5 ml of methanol are added, 50 μL of a 1000 ppm concentration of pyrene in methanol as an internal standard is added, and the silane coupling agent is further released. 0.5 ml of an aqueous hydrochloric acid solution (concentration 20% by weight) was added. Thereafter, by treating with an ultrasonic disperser for 20 minutes, the surfactant and the silane coupling agent are extracted into methanol, and solid-liquid separation is performed using a centrifuge. The supernatant obtained by solid-liquid separation was collected and filtered through a non-aqueous 0.45 μm chromatodisc to prepare a test solution.

Measure the concentration of the silane coupling agent in this test solution using a GC / MS apparatus. Then, the measured silane coupling agent concentration [μg / ml] in the test solution, the weight of the polymer particle powder used as the sample (sample weight [g]), and the amount of the extract (extract solution amount [ ml]), the silane coupling agent content [μg / g] per 1 g of the polymer particles and the silane coupling agent content [wt%] in the polymer particles are determined by the following calculation formula. The amount of the extract is 5 ml.

Silane coupling agent content per gram of polymer particles [μg / g]
= {Silane coupling agent concentration in test solution [μg / ml]
× Extraction liquid volume [ml]}
÷ Sample weight [g]
Silane coupling agent content in polymer particles [wt%]
= 100 × 10 ⁻⁶
× {Concentration of silane coupling agent in test solution [μg / ml]
× Extraction liquid volume [ml]}
÷ Sample weight [g]

The silane coupling agent concentration is calculated from a peak area value on the obtained chromatogram using a calibration curve prepared in advance from a silane coupling agent stock solution using a GC / MS apparatus. In addition, when the polymer particles contain a plurality of types of silane coupling agents, for each of these silane coupling agents, create a calibration curve, calculate the silane coupling agent concentration by the created calibration curve, The total silane coupling agent concentration of each calculated silane coupling agent is defined as the “silane coupling agent concentration [μg / ml] in the test solution” in the above calculation formula, and the silane coupling agent content of the polymer particles is Ask.

<Measurement conditions>
Column: Phenomenex ZB-1
(Film thickness 1μm, inner diameter 0.25mm, length 60m)
Carrier gas: helium Carrier gas flow rate: 1.0 ml / min
Inlet temperature: 300 ° C

[Evaluation method of redispersibility after sedimentation of polymer particle dispersion]
80 g of the polymer particle dispersion is put into a sample tube having an internal volume of 100 ml, and left to stand for 120 hours at a place where the atmospheric temperature is 20 to 25 ° C. After standing, the polymer particle dispersion is redispersed by dispersing for 10 minutes with an ultrasonic homogenizer. The particle size distribution of the polymer particle dispersion obtained after redispersion is measured in the same manner as the volume-based particle size distribution measurement in the volume average particle size measurement method described above, and is measured by the volume average particle size measurement method described above. It is confirmed whether the particle size distribution has a particle size peak that is at least twice the volume average particle size of the polymer particles. Further, it is visually confirmed whether or not there is a remaining sediment that cannot be dispersed on the bottom surface of the sample tube. And based on these confirmation results, the redispersibility after the sedimentation of the polymer particle dispersion is evaluated according to the following criteria.

×: There is a peak with a particle size that is twice or more of the volume average particle size. Δ: There is no peak with a particle size that is twice or more of the volume average particle size, but there is a residue of undispersed sediment on the bottom of the sample tube. Yes: There is no peak of particle size more than twice the volume average particle size, and there is no residual sediment that cannot be dispersed on the bottom of the sample tube

[Evaluation method of redispersibility after powder reslurry of polymer particle dispersion]
The polymer particle dispersion is spray-dried with a spray dryer, and then pulverized and dispersed to primary particles with an airflow pulverizer, and the resulting polymer particle powder is recovered. The conditions for spray drying and pulverization / dispersion are the same as those in the method for measuring the specific surface area of the polymer particles.

4 g of the recovered polymer particle powder is added to 16 g of the same dispersion medium as that contained in the polymer particle dispersion before spray drying, and dispersed and redispersed for 15 minutes with an ultrasonic homogenizer. The particle size distribution of the polymer particle dispersion obtained after redispersion is measured in the same manner as the volume-based particle size distribution measurement in the volume average particle size measurement method described above, and is measured by the volume average particle size measurement method described above. It is confirmed whether the particle size distribution has a particle size peak that is at least twice the volume average particle size of the polymer particles. Further, it is visually confirmed whether or not there is a remaining sediment that cannot be dispersed on the bottom surface of the sample tube. And based on these confirmation results, the redispersibility after the sedimentation of the polymer particle dispersion is evaluated according to the following criteria.

×: There is a peak with a particle size that is twice or more of the volume average particle size. Δ: There is no peak with a particle size that is twice or more of the volume average particle size, but there is a residue of undispersed sediment on the bottom of the sample tube. Yes: There is no peak of particle size more than twice the volume average particle size, and there is no residual sediment that cannot be dispersed on the bottom of the sample tube

[Seed Particle Production Example 1]
In a separable flask (polymerizer) equipped with a stirrer, a thermometer and a reflux condenser, 1450 g of water as an aqueous medium, 250 g of methyl methacrylate as a (meth) acrylic acid ester monomer, and a molecular weight regulator The n-octyl mercaptan (2.5 g) was charged, the inside of the separable flask was purged with nitrogen while stirring the contents of the separable flask, and the internal temperature of the separable flask was raised to 70 ° C. Further, an aqueous solution obtained by dissolving 1.50 g of potassium persulfate as a polymerization initiator in 50 g of water while keeping the internal temperature of the separable flask at 70 ° C. was added to the contents of the separable flask. The polymerization reaction was performed for a time.

The reaction liquid after polymerization was filtered through a 400 mesh (mesh 32 μm) wire mesh to prepare a slurry containing 14% by weight of seed particles (referred to as seed particles (1)) made of polymethyl methacrylate as a solid content. The seed particles (1) contained in this slurry were true spherical particles having a volume average particle diameter of 0.41 μm.

[Seed Particle Production Example 2]
In a separable flask polymerizer equipped with a stirrer and a thermometer, 1650 g of water as an aqueous medium, 180 g of methyl methacrylate as a (meth) acrylic acid ester monomer, and n-octyl mercaptan as a molecular weight modifier 0 .9 g, and the seed particle (1) slurry produced in Seed Particle Production Example 1 was added to 17.5 g as a solid content (seed particle), and the inside was purged with nitrogen while stirring the contents. The internal temperature of the reactor was raised to 70 ° C. Further, an aqueous solution prepared in advance by dissolving 0.9 g of potassium persulfate as a polymerization initiator in 50 g of water while maintaining the internal temperature of the reactor at 70 ° C. was added to the contents of the separable flask for 12 hours. A polymerization reaction was performed.

The reaction liquid after polymerization was filtered through a 400 mesh (mesh opening 32 μm) wire mesh to prepare a slurry containing 14% by weight of seed particles (hereinafter referred to as seed particles (2)) made of polymethyl methacrylate as a solid content. . The seed particles (2) contained in this slurry were true spherical particles having a volume average particle diameter of 1.05 μm.

[Example 1]
<1> Polymerization process In a separable flask (polymerizer) equipped with a stirrer, a thermometer and a reflux condenser, polyoxyethylene nonylphenyl which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety Sodium ether phosphate (manufactured by Toho Chemical Co., Ltd., product name “Phosphanol (registered trademark) LO-529”) as a pure component of 10 g (2 parts by weight per 100 parts by weight of polymer particles) in 1500 g of ion-exchanged water An aqueous solution prepared in advance by adding and dissolving is added, 350 g of butyl acrylate (BA) as a (meth) acrylic acid ester monomer, and ethylene glycol dimethacrylate (EGDMA) as a polyfunctional vinyl monomer. ) 150 g, 5 g of n-dodecyl mercaptan as a molecular weight regulator, and a polymerization initiator The monomer composition prepared in advance by dissolving 2.5 g of 2,2′-azobisisobutyronitrile was further mixed. A high-speed dispersion / emulsifier (product name “Homomixer MARKII 2.5 type” manufactured by PRIMIX Co., Ltd.) was inserted into the mixed solution, and the mixture was processed at a rotational speed of 8000 rpm for 10 minutes to obtain an emulsion.

An amount (178.6 g) of solid particles (seed particles) of 25.0 g was added to the slurry of seed particles (1) obtained in Seed Particle Production Example 1 and stirred at 30 ° C. for 2 hours. Then, a dispersion liquid in which the monomer composition was absorbed into the seed particles was prepared. Thereafter, the separable flask containing the dispersion was heated, and the polymerization reaction was carried out while stirring for 5 hours at an internal temperature of 50 ° C. and then for 3 hours at 80 ° C. to obtain a polymer particle dispersion. It was.

<2> Silane coupling treatment step The solid content concentration of the polymer particle dispersion obtained by the polymerization reaction was 25% by weight. The solid content concentration was adjusted by the above-described method for the polymer particle dispersion. That is, the solid content concentration was adjusted to 20% by weight by adding an addition amount of ion-exchanged water calculated by the above-described method to the polymer particle dispersion.

100 g of the polymer particle dispersion liquid whose solid content concentration was adjusted to 20% by weight was extracted into a 200 ml beaker containing a stirrer, and the beaker was placed in a water bath kept at 30 ° C. To the polymer particle dispersion in the installed beaker, 3- (2-aminoethyl) aminopropyltrimethoxysilane (manufactured by Toray Dow Corning Silicone Co., Ltd., model number “XIAMETER (registered trademark)” as an amino silane coupling agent ) "OFS-6020 SILANE"; hereinafter abbreviated as "OFS-6020") 0.1g (0.5 parts by weight with respect to 100 parts by weight of the polymer particles) as a pure component, and the contents of the beaker with a stirrer The mixture was subjected to silane coupling treatment for 5 hours at 30 ° C. with stirring.

<3> Filtration (classification) step After cooling the internal temperature of the silane-coupled polymer particle dispersion to 25 ° C., it is filtered through a 400 mesh (mesh opening 32 μm) wire mesh to remove foreign substances such as nonstandard particles (Classification) was performed to obtain a final polymer particle dispersion.

<4> Evaluation Step For the obtained polymer particle dispersion, each evaluation (measurement of solid content concentration, measurement of volume average particle diameter of polymer particles and coefficient of variation of volume-based particle diameter, ratio of polymer particles) Measurement of surface area, measurement of surfactant content of polymer particles, measurement of surfactant coating amount of polymer particles, measurement of silane coupling agent content of polymer particles, modification of polymer particles with silane coupling agent Measurement of the amount, evaluation of redispersibility after settling, and evaluation of redispersibility after powder reslurry) were performed by the methods described above. The results of each evaluation are the composition of the monomer mixture used in the polymerization step, the dispersion medium used, the type of surfactant added before polymerization, the type of surfactant added after polymerization, and the type of silane coupling agent. And the amount added (parts by weight with respect to 100 parts by weight of polymer particles). The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 0.81 μm, and the variation coefficient of the volume-based particle diameter was 13.1%.

[Example 2]
Instead of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino silane coupling agent, 3- (2-aminoethyl) aminopropylmethyldimethoxysilane (Toray Dow Corning Silicone Co., Ltd., model number “DOW” Polymer particle dispersions were produced and evaluated in the same manner as in Example 1 except that CORNING (registered trademark) Z-6023 SILANE (hereinafter abbreviated as “Z-6023”) was used.

Example 3
Instead of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino-based silane coupling agent, 3-aminopropyltriethoxysilane (manufactured by Momentive Performance Materials, product name “SILQUEST (registered trademark) A-” A polymer particle dispersion was prepared and evaluated in the same manner as in Example 1 except that “1100 SILANE” (abbreviated as “A-1100” in the table) was used.

Example 4
Except for changing the amount of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino-based silane coupling agent to 0.02 g (0.1 part by weight with respect to 100 parts by weight of polymer particles), In the same manner as in Example 1, polymer particle dispersions were produced and evaluated.

Example 5
Except for changing the amount of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino silane coupling agent to 0.4 g (2.0 parts by weight with respect to 100 parts by weight of polymer particles), In the same manner as in Example 1, polymer particle dispersions were produced and evaluated.

Example 6
Example 1 except that the amount of ion-exchanged water added at the time of adjusting the solid content concentration after the polymerization reaction was changed to change the solid content concentration of the polymer particle dispersion to 10% by weight. In the same manner, polymer particle dispersions were produced and evaluated.

Example 7
At the time of adjusting the solid content concentration after the polymerization reaction, the polymer particle dispersion after the polymerization reaction is concentrated by an ultrafiltration device (manufactured by NGK Corporation), and the solid content concentration of the polymer particle dispersion is 50 wt. A polymer particle dispersion was produced and evaluated in the same manner as in Example 1 except that the amount was adjusted so as to adjust to%.

Example 8
<1> Polymerization process In a separable flask polymerization apparatus equipped with a stirrer, a thermometer, and a reflux condenser, 1200 g of water as an aqueous medium, 60 g of methyl methacrylate as a (meth) acrylate monomer, and molecular weight adjustment Then, 0.60 g of n-octyl mercaptan as an agent was charged, the inside of the separable flask was purged with nitrogen while stirring the contents of the separable flask, and the internal temperature of the separable flask was raised to 70 ° C. Further, an aqueous solution prepared in advance by dissolving 0.32 g of potassium persulfate as a polymerization initiator in 50 g of water while keeping the internal temperature of the separable flask at 70 ° C. was added to the contents of the separable flask. The polymerization reaction was performed for a time. Thereby, a polymerization reaction liquid containing seed particles was obtained.

Thereafter, 230 g of methyl methacrylate as a new (meth) acrylic acid ester monomer, 10 g of allyl methacrylate (AMA) as a polyfunctional vinyl monomer, and n-octyl mercaptan as a molecular weight regulator. A mixture prepared by dissolving 40 g was added to the polymerization reaction solution, the inside of the separable flask was again purged with nitrogen, and the internal temperature of the separable flask was raised to 70 ° C. While maintaining the internal temperature of the separable flask at 70 ° C., 1.28 g of potassium persulfate as a polymerization initiator was dissolved in 50 g of water, and an aqueous solution prepared in advance was added to the contents of the separable flask, followed by polymerization for 12 hours. Reaction was performed to obtain a polymer particle dispersion.

<2> Silane coupling treatment process (including surfactant coating treatment process in this embodiment)
The concentration of the solid content of the polymer particle dispersion obtained by the polymerization reaction was 20% by weight. 100 g of this polymer particle dispersion having a solid concentration of 20% by weight was extracted into a 200 ml beaker containing a stirrer, and the beaker was placed in a water bath kept at 30 ° C. Polyoxyethylene nonylphenyl ether sodium phosphate (product name, manufactured by Toho Chemical Co., Ltd.), an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, in the polymer particle dispersion in the installed beaker 0.4% of “Phosphanol (registered trademark) LO-529”) (2 parts by weight with respect to 100 parts by weight of polymer particles) was added, and the contents of the beaker were stirred with a stirrer for 1 hour The active agent is coated.

Thereafter, 0.1 g (0.5 part by weight with respect to 100 parts by weight of polymer particles) of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino silane coupling agent as a pure component was placed in a 200 ml beaker. Then, the contents of the beaker were stirred with a stirrer and subjected to silane coupling treatment at an internal temperature of 30 ° C. for 5 hours.

Then, a polymer particle dispersion was produced by carrying out a filtration (classification) step in the same manner as in Example 1, and the polymer particle dispersion was evaluated in the same manner as in Example 1. The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 0.51 μm, and the variation coefficient of the volume-based particle diameter was 14.1%.

Example 9
Example 3 except that 3- (2-aminoethyl) aminopropylmethyldimethoxysilane (Z-6023) was used in place of 3- (2-aminoethyl) aminopropyltrimethoxysilane as the amino-based silane coupling agent. In the same manner as in No. 8, polymer particle dispersions were produced and evaluated.

Example 10
Instead of polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both polyoxyethylene chain and phosphate ester moiety, an anionic interface having polyoxyethylene chain and no phosphate ester moiety Except that polyoxyethylene distearic acid ester (made by Daiichi Kogyo Seiyaku Co., Ltd., product name “Neugen (registered trademark) DS-601”), which is a nonionic surfactant as an activator, was used. Similarly, the polymer particle dispersion was evaluated.

Example 11
The polymer particle dispersion was evaluated in the same manner as in Example 1 except that methyl methacrylate (MMA) was used as the (meth) acrylic acid ester monomer instead of butyl acrylate. The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 0.82 μm, and the variation coefficient of the volume-based particle diameter was 14.8%.

Example 12
From the mixture of 350 g of butyl acrylate and 150 g of ethylene glycol dimethacrylate, 480 g of styrene (St) as a styrenic monomer and 20 g of divinylnylbenzene (DVB) as a polyfunctional vinyl monomer. The polymer particle dispersion was evaluated in the same manner as in Example 1 except that the mixture was changed to a mixture of The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 0.84 μm, and the variation coefficient of the volume-based particle diameter was 15.0%.

Example 13
Except that the monomer mixture was changed from a mixture of 350 g of butyl acrylate and 150 g of ethylene glycol dimethacrylate to a mixture of 300 g of methyl methacrylate, 100 g of styrene and 100 g of ethylene glycol dimethacrylate, the same as in Example 1. The polymer particle dispersion was evaluated. The volume average particle size of the polymer particles in the obtained polymer particle dispersion was 0.83 μm, and the variation coefficient of the volume-based particle size was 14.4%.

Example 14
<1> Polymerization process In a separable flask equipped with a stirrer, a thermometer and a reflux condenser, di (2-ethylhexyl) sulfosuccinate sodium (day) which is an anionic surfactant having neither a polyoxyethylene chain nor a phosphate ester site 500 g of ion-exchanged water with 5 g (1 part by weight per 100 parts by weight of polymer particles) added as a pure component (product name “Rapisol (registered trademark) A-80” manufactured by Oil Co., Ltd.) was added and (meth) acrylic 400 g of butyl acrylate (BA) as an acid ester monomer, 100 g of ethylene glycol dimethacrylate (EGDMA) as a polyfunctional vinyl monomer, and 2,2′-azobisisobutyrate as a polymerization initiator A monomer composition prepared in advance by dissolving 2.5 g of ronitrile was further mixed. A high-speed dispersion / emulsifier (product name “Homomixer MARKII 2.5 type” manufactured by PRIMIX Co., Ltd.) was inserted into the mixed solution, and the mixture was processed at a rotational speed of 8000 rpm for 10 minutes to obtain an emulsion.

An amount (1850.0 g) of solid particles (seed particles) of 185.0 g was added to the slurry of seed particles (2) obtained in Seed Particle Production Example 2 and stirred at 30 ° C. for 3 hours. Then, a dispersion liquid in which the monomer composition was absorbed into the seed particles was prepared.

In the dispersion liquid in which the monomer composition is absorbed in the seed particles, pure polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, is used. An aqueous solution prepared in advance by adding and dissolving 10 g (2 parts by weight with respect to 100 parts by weight of polymer particles) in 500 g of ion-exchanged water was added and mixed. Thereafter, the separable flask was heated, and the polymerization reaction was carried out while stirring for 5 hours at an internal temperature of 50 ° C. and then for 3 hours at 80 ° C. to obtain a polymer particle dispersion.

<2> Silane coupling treatment step The solid content concentration of the polymer particle dispersion obtained by the polymerization reaction was 20% by weight. A silane coupling treatment was performed in the same manner as in the silane coupling treatment step of Example 1 except that the addition of ion exchange water for adjusting the solid content concentration to 20% by weight was omitted.

Then, a polymer particle dispersion was produced by carrying out a filtration (classification) step in the same manner as in Example 1, and the polymer particle dispersion was evaluated in the same manner as in Example 1. The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 3.02 μm, and the variation coefficient of the volume-based particle diameter was 10.2%.

Example 15
Ion exchange water in which the addition amount of the seed particle (2) slurry is changed to an amount (240.0 g) at which the solid content (seed particles) is 24.0 g, and sodium polyoxyethylene nonylphenyl ether phosphate is further dissolved. A polymer particle dispersion was produced and evaluated in the same manner as in Example 14 except that the amount of was changed to 1400 g. The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 6.00 μm, and the variation coefficient of the volume-based particle diameter was 9.1%.

Example 16
Polymer particles in the same manner as in Example 15, except that the amount of sodium polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester site, was changed to 20 g. Dispersions were prepared and evaluated. The volume average particle size of the polymer particles in the obtained polymer particle dispersion was 6.01 μm, and the variation coefficient of the volume-based particle size was 9.3%.

Example 17
In the same manner as in Example 1, except that the amount of sodium polyoxyethylene nonylphenyl ether phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester site, was changed to 4.0 g. Combined particle dispersions were prepared and evaluated. The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 0.82 μm, and the variation coefficient of the volume-based particle diameter was 14.3%.

Example 18
A mixed liquid of 500 g of ion-exchanged water and 500 g of isopropyl alcohol (IPA) as an aqueous medium is added to 100 g of the polymer particle dispersion prepared according to Example 1, and the concentration of solids is reduced by an ultrafilter device. Concentration to 20% by weight gave a solvent-based polymer particle dispersion. The volume average particle diameter of the polymer particles in the obtained polymer particle dispersion was 0.84 μm, and the variation coefficient of the volume-based particle diameter was 14.6%.

[Comparative Example 1]
Instead of polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, an anionic surfactant having neither a polyoxyethylene chain nor a phosphate ester moiety Polymer particle dispersion in the same manner as in Example 1 except that sodium di (2-ethylhexyl) sulfosuccinate (manufactured by NOF Corporation, product name “Lapisol (registered trademark) A-80”) is used. Were manufactured and evaluated. The volume average particle size of the polymer particles in the obtained polymer particle dispersion was 0.81 μm, and the variation coefficient of the volume-based particle size was 13.5%.

[Comparative Example 2]
A polymer particle dispersion was produced and evaluated in the same manner as in Example 1 except that the silane coupling treatment with an amino silane coupling agent was not performed.

[Comparative Example 3]
The amount of sodium polyoxyethylene nonylphenyl ether phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, is 3.0 g (0.6 parts by weight based on 100 parts by weight of polymer particles). The polymer particle dispersion was produced and evaluated in the same manner as in Example 1 except that the change was made to).

The volume average particle size of the polymer particles in the obtained polymer particle dispersion was 0.83 μm, and the variation coefficient of the volume-based particle size was 13.9%. Further, the obtained polymer particle dispersion was difficult to redisperse, and the evaluation of redispersibility was “x” (poor). This is presumably because a sufficient amount of coupling reaction was not performed in the silane coupling treatment step because the amount of the surfactant coated on the polymer particles was small.

[Comparative Example 4]
The amount of sodium polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, was changed to 30 g (6 parts by weight relative to 100 parts by weight of polymer particles). Except for this, polymer particle dispersions were produced and evaluated in the same manner as in Example 1.

The volume average particle size of the polymer particles in the obtained polymer particle dispersion was 6.04 μm, and the variation coefficient of the volume-based particle size was 8.8%. Further, the obtained polymer particle dispersion was difficult to redisperse, and the evaluation of redispersibility was “x” (poor). This is presumably because if the amount of the surfactant adhering to the surface of the polymer particles is too large, the surfactant strongly binds the polymer particles after sedimentation.

[Comparative Example 5]
Instead of amino silane coupling agent (3- (2-aminoethyl) aminopropyltrimethoxysilane), vinyltrimethoxysilane (manufactured by Dow Corning Silicone Co., Ltd., model number), which is a non-amino silane coupling agent A polymer particle dispersion was produced and evaluated in the same manner as in Example 8 except that “DOW CORNING (registered trademark) Z-6300 SILANE” was used.

[Comparative Example 6]
Instead of polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, an anionic surfactant having neither a polyoxyethylene chain nor a phosphate ester moiety A polymer particle dispersion was produced in the same manner as in Example 8, except that sodium dodecylbenzenesulfonate (product name “Neogen (registered trademark) S-20F” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was used. And evaluated.

[Comparative Example 7]
Instead of polyoxyethylene nonylphenyl ether sodium phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety, an anionic surfactant having neither a polyoxyethylene chain nor a phosphate ester moiety Sodium dodecylbenzenesulfonate (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name “Neogen (registered trademark) S-20F”), and 3- (2-aminoethyl) aminopropyl as an amino silane coupling agent A polymer particle dispersion was produced and evaluated in the same manner as in Example 8 except that 3- (2-aminoethyl) aminopropylmethyldimethoxysilane (Z-6023) was used instead of trimethoxysilane.

[Comparative Example 8]
A polymer in the same manner as in Example 8, except that the surfactant is not coated with sodium polyoxyethylene nonylphenyl ether phosphate, which is an anionic surfactant having both a polyoxyethylene chain and a phosphate ester moiety. Particle dispersions were produced and evaluated.

[Comparative Example 9]
Except for changing the amount of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino silane coupling agent to 0.002 g (0.01 parts by weight with respect to 100 parts by weight of polymer particles), In the same manner as in Example 1, polymer particle dispersions were produced and evaluated.

The obtained polymer particle dispersion was difficult to redisperse, and the evaluation of redispersibility was “x” (poor). This is because in this comparative example, the amount of the amino silane coupling agent is too small, so that a sufficient amount of coupling reaction is not performed, and the modification of the polymer particle surface by the amino silane coupling agent is insufficient. It is thought that it became.

[Comparative Example 10]
Except for changing the amount of 3- (2-aminoethyl) aminopropyltrimethoxysilane as an amino-based silane coupling agent to 1.0 g (5.0 parts by weight with respect to 100 parts by weight of polymer particles), In the same manner as in Example 1, polymer particle dispersions were produced and evaluated.

The obtained polymer particle dispersion was difficult to redisperse, and the evaluation of redispersibility was “x” (poor). This is because, in this comparative example, the amount of the amino silane coupling agent is too large, so that a condensation reaction between the amino silane coupling agent and water occurs, and the product of the condensation reaction binds the polymer particles to each other. It is considered that the dispersibility is impaired because aggregation of the coalesced particles occurs.

[Comparative Example 11]
At the time of adjusting the solid content concentration after the polymerization reaction, the polymer particle dispersion after the polymerization reaction is concentrated by an ultrafiltration device (manufactured by NGK Co., Ltd.), so that the solid content concentration of the polymer particle dispersion is 60 wt. A polymer particle dispersion was produced and evaluated in the same manner as in Example 1 except that the amount was adjusted so as to adjust to%.

The obtained polymer particle dispersion was difficult to redisperse, and the evaluation of redispersibility was “x” (poor). This is thought to be because, in this comparative example, the polymer particle concentration is too high, so that the amount of sediment when settling is large, the deposition density between the polymer particles increases, and a strong deposit is formed. It is done.

In Table 1, POEPS represents sodium polyoxyethylene nonylphenyl ether phosphate, POEDS represents polyoxyethylene distearate ester, DSS represents sodium di (2-ethylhexyl) sulfosuccinate, and DBSS represents dodecylbenzenesulfone. Represents the acid salt.

In Table 1, the surfactant contents and coating amounts of Examples 14 to 16 were determined based on the surfactant (sodium di (2-ethylhexyl) sulfosuccinate) having neither a polyoxyethylene chain nor a phosphate ester moiety. Not only the total surfactant content and coverage, but also the content and coverage of only the surfactant (polyoxyethylene nonylphenyl ether sodium phosphate) having both polyoxyethylene chains and phosphate ester sites Show.

As described above, the polymer particle dispersions of Examples 1 to 18 according to the present invention have a solid content (polymer particle concentration) of 50% by weight or less, per unit surface area of the polymer particle surface. The content of the surfactant having at least one of the adhering polyoxyethylene chain and the phosphate ester site is 0.6 to 15.0 mg / m ² and adheres per unit surface area of the polymer particle surface. When the content of the amino-based silane coupling agent is 0.05 to 3.0 mg / m ² , the polymer particle dispersion of Comparative Example 8 in which no surfactant is used, the unit surface area of the polymer particle surface In Comparative Examples 3 and 4, the content of the surfactant having at least one of a polyoxyethylene chain and a phosphate ester site adhering to the periphery is less than 0.6 mg / m ² or more than 15.0 mg / m ² polymerization Body particle dispersion, polymer particle dispersion of Comparative Examples 1, 6 and 7 using only a surfactant having neither polyoxyethylene chain nor phosphate ester site, Comparative Example 2 using no silane coupling agent The content of the amino silane coupling agent adhering per unit surface area of the polymer particle dispersion and the polymer particle surface is less than 0.05 mg / m ² or 3.0 mg /% with respect to 100% by weight of the polymer particles. Compared to the polymer particle dispersion liquid of Comparative Examples 9 and 10 that exceeds m ² and the polymer particle dispersion liquid that has a solid content (polymer particle concentration) of more than 50% by weight, the redispersibility is improved. I found it excellent.

As described above, the polymer particle dispersions of Examples 1 to 18 according to the present invention have a solid content (polymer particle concentration) of 50% by weight or less, and have polyoxyethylene chains and phosphate ester sites. The surfactant having at least one of the following is contained in an amount of 0.7 to 5.0 parts by weight with respect to 100 parts by weight of the polymer particles, and the amino silane coupling agent is 0.05 to 4 parts by weight with respect to 100 parts by weight of the polymer particles. By containing 0.0 part by weight, the content of the surfactant having at least one of the polymer particle dispersion, the polyoxyethylene chain and the phosphate ester portion of Comparative Example 8 in which no surfactant is used is the polymer particle 100. Less than 0.7 parts by weight or more than 5.0 parts by weight of the polymer particle dispersion of Comparative Examples 3 and 4, using only a surfactant having no polyoxyethylene chain and phosphate site Ratio The polymer particle dispersion of Examples 1, 6, and 7, the polymer particle dispersion of Comparative Example 2 not using a silane coupling agent, and the content of the amino silane coupling agent relative to 100 parts by weight of the polymer particles Polymer particle dispersion of Comparative Examples 9 and 10 which is less than 0.05 parts by weight or more than 4.0 parts by weight, and polymer particle dispersion in which the solid content (polymer particle concentration) is more than 50% by weight It was found that the redispersibility was excellent compared to the liquid.

Example 19
In this embodiment, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino-based silane coupling agent are added to water and reacted with each other to produce these reaction products. Was obtained as a dispersing agent.

That is, first, 80 g of ion-exchanged water is placed in a 200 ml beaker containing a stirrer, and the ion-exchanged water contains at least one of a polyoxyethylene chain and a phosphate ester moiety. 0.4 g of pure oxyethylene nonylphenyl ether phosphate (product name “Phosphanol (registered trademark) LO-529” manufactured by Toho Chemical Co., Ltd.) and 3- ( 0.1 g of 2-aminoethyl) aminopropyltrimethoxysilane (OFS-6020) as a pure component was added, and a beaker was placed in a water bath kept at 30 ° C. While stirring the contents of the beaker with a stirrer, the anionic surfactant and the amino silane coupling agent were reacted at an internal temperature of 30 ° C. for 3 hours. Thereby, the dispersion medium which contains the reaction product of an anionic surfactant and an amino-type silane coupling agent in water as a dispersing agent was obtained.

Example 20
In this example, it was verified whether or not a polymer particle dispersion excellent in redispersibility could be obtained in the same manner as in Example 8 by dispersing polymer particles in the dispersion medium obtained in Example 19.

That is, first, a polymer particle dispersion liquid having a solid content concentration of 20% by weight prepared in the same manner as in the polymerization step <1> of Example 8 was sprayed in the same manner as in the above-mentioned “Method for measuring specific surface area of polymer particles”. The powder was processed by drying and pulverization and dispersion to obtain polymer particle powder. 20 g of the obtained polymer particle powder was added to the dispersion medium obtained in Example 19. After the addition, the mixture was dispersed with an ultrasonic homogenizer for 10 minutes, and the contents of the beaker were stirred with a stirrer for 1 hour at an internal temperature of 30 ° C. to obtain a final product polymer particle dispersion. The amount of the anionic surfactant used for the preparation of the dispersion medium is 2 parts by weight with respect to 100 parts by weight of the polymer particles, and the amount of the amino silane coupling agent used for the preparation of the dispersion medium is the polymer. 0.5 parts by weight per 100 parts by weight of the particles.

As a result of evaluating the redispersibility of the polymer particle dispersion of the final product in the same manner as in Example 1, both “redispersibility after sedimentation” and “redispersibility after powder reslurry” are both “◯”, As in Example 8, it was confirmed that a polymer particle dispersion excellent in redispersibility was obtained.

Example 21
As in Example 19, except that 3- (2-aminoethyl) aminopropylmethyldimethoxysilane was used instead of 3- (2-aminoethyl) aminopropyltrimethoxysilane as the amino silane coupling agent. To obtain a dispersion medium.

[Example 22]
A final product polymer particle dispersion was obtained in the same manner as in Example 20, except that the dispersion medium obtained in Example 21 was used instead of the dispersion medium obtained in Example 19. As a result of evaluating the redispersibility of the polymer particle dispersion of the final product in the same manner as in Example 1, both “redispersibility after sedimentation” and “redispersibility after powder reslurry” are both “◯”, It was confirmed that a polymer particle dispersion excellent in redispersibility was obtained.

Example 23
(Production of dispersant)
In this example, a surfactant containing at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent are mixed and reacted with each other to disperse these reaction products. An agent was obtained.

That is, first, a polyoxyethylene nonylphenyl ether sodium phosphate (Toho Chemical Co., Ltd.) as an anionic surfactant having at least one of a polyoxyethylene chain and a phosphate ester moiety in a 50 ml beaker containing a stirrer. 32 g of pure product (product name “phosphanol (registered trademark) LO-529”) manufactured by the company and 3- (2-aminoethyl) aminopropyltrimethoxysilane (OFS-6020) as an amino-based silane coupling agent ) Was added as a pure component, and a beaker was placed in a water bath kept at 30 ° C. While stirring the contents of the beaker with a stirrer, the anionic surfactant and the silane coupling agent are reacted for 2 hours at an internal temperature of 30 ° C., and the anionic surfactant and the amino silane coupling agent are submerged in water. A dispersant containing the reaction product (hereinafter referred to as “dispersant [1]”) was prepared.

(Analysis of dispersant [1])
Dispersant [1] 0.1 g was added to 50 ml of methanol, treated with an ultrasonic disperser for 10 minutes, and then diluted 10-fold with methanol. Add 5 ml of 10-fold diluted methanol solution to a test tube, add 50 μL of 1000 ppm acetone solution as an internal standard to the test tube, treat with an ultrasonic disperser for 10 minutes, and then use a non-aqueous 0.45 μm chromatodisc. A test evaluation liquid [1] was prepared by filtration.

On the other hand, 0.5 ml of hydrochloric acid with a concentration of 20% by weight as a free liquid was put into 5 ml of the prepared test evaluation liquid [1], treated with an ultrasonic disperser for 10 minutes, and then filtered with a non-aqueous 0.45 μm chromatodisc. As a result, a test evaluation solution [2] was prepared.

The prepared test evaluation liquids [1] and [2] were analyzed by GC / MS in the same manner as GC / MS in [Method for measuring content of silane coupling agent in polymer particles] to obtain a chromatogram. .

(Analytical result of dispersant [1])
The test evaluation liquid [1] before release had a low peak intensity derived from the silane coupling agent, whereas the test evaluation liquid [2] after release had a high peak intensity derived from the silane coupling agent. Thereby, it was confirmed that the dispersant [1] before release contains a reaction product produced by a reaction between the anionic surfactant and the amino silane coupling agent.

Example 24
In this example, by dispersing polymer particles in the dispersant (1) containing the reaction product of the anionic surfactant and amino silane coupling agent prepared in Example 23, Example 8 and Similarly, it was verified whether a polymer particle dispersion excellent in redispersibility could be obtained.

That is, first, 100 g of a polymer particle dispersion having a solid content concentration of 20% by weight prepared in the same manner as in the <1> polymerization step of Example 8 was extracted and placed in a 200 ml beaker containing a stirrer. A beaker was placed in a water bath kept at ℃. To the polymer particle dispersion in the installed beaker, 0.5 g of the dispersant (1) prepared in Example 23 (2.5 parts by weight with respect to 100 parts by weight of the polymer particles) was added, and the beaker was mixed with a stirrer. The contents were stirred for 3 hours at an internal temperature of 30 ° C. to obtain a final polymer particle dispersion.

As a result of evaluating the redispersibility of the polymer particle dispersion of the final product in the same manner as in Example 1, both “redispersibility after sedimentation” and “redispersibility after powder reslurry” are both “◯”, As in Example 8, it was confirmed that a polymer particle dispersion excellent in redispersibility was obtained.

The present invention can be implemented in various other forms without departing from the spirit or main features thereof. For this reason, the above-described embodiment is merely an example in all respects and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not restricted by the text of the specification. Further, all modifications and changes belonging to the equivalent scope of the claims are within the scope of the present invention.

This application claims priority based on Japanese Patent Application No. 2015-185422 filed in Japan on September 23, 2016. By this reference, the entire contents thereof are incorporated into the present application.

Claims (19)

A polymer particle dispersion in which polymer particles are dispersed in an aqueous medium,
The concentration of the polymer particles is 50% by weight or less,
On the surface of the polymer particles, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site, and an amino silane coupling agent are attached,
The content of the surfactant attached per unit surface area of the polymer particle surface is 0.6 to 15.0 mg / m ² ;
A polymer particle dispersion, wherein the content of the amino silane coupling agent adhering per unit surface area of the polymer particle surface is 0.05 to 3.0 mg / m ² . A polymer particle dispersion in which polymer particles are dispersed in an aqueous medium,
The concentration of the polymer particles is 50% by weight or less,
Containing 0.7 to 5.0 parts by weight of a surfactant having at least one of a polyoxyethylene chain and a phosphoric acid ester moiety with respect to 100 parts by weight of the polymer particles;
A polymer particle dispersion comprising 0.05 to 4.0 parts by weight of an amino silane coupling agent with respect to 100 parts by weight of the polymer particles. 3. The polymer particle according to claim 1, wherein the surfactant is at least one of an anionic surfactant having a polyoxyethylene chain and a nonionic surfactant having a polyoxyethylene chain. Dispersion. The polymer particle dispersion according to any one of claims 1 to 3, wherein the surfactant has a phosphate ester moiety. The polymer particle dispersion according to any one of claims 1 to 4, wherein the amino silane coupling agent is an amino silane coupling agent having a solubility in water of 1.0% by weight or more. liquid. The polymer particles are at least one of a (meth) acrylic polymer, a styrene polymer, a (meth) acryl-styrene copolymer, a polyurethane polymer, a polyethylene terephthalate polymer, and a silicone polymer. 6. The polymer particle dispersion according to claim 1, wherein the polymer particle dispersion is composed of: 7. The polymer particle dispersion according to claim 1, wherein the polymer particles have a volume average particle diameter of 0.1 to 50 μm. The polymer particle dispersion according to any one of claims 1 to 7, wherein the volume-based particle diameter variation coefficient of the polymer particles is 20% or less. A dispersant comprising a reaction product of a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site and an amino silane coupling agent. A dispersion medium comprising at least one of water and a polar organic solvent, and the dispersant according to claim 9. A polymer particle dispersion in which polymer particles are dispersed in the dispersion medium according to claim 10. A coating agent comprising the polymer particle dispersion according to any one of claims 1 to 8 and 11, and a binder. An anti-blocking agent comprising the polymer particle dispersion according to any one of claims 1 to 8 and 11. A pore-forming agent comprising the polymer particle dispersion according to any one of claims 1 to 8 and 11. On the surface of the polymer particles, a surfactant having at least one of a polyoxyethylene chain and a phosphate ester site, and an amino silane coupling agent are attached,
The content of the surfactant attached per unit surface area of the polymer particle surface is 0.6 to 15.0 mg / m ² ;
Polymer particles, wherein the content of the amino silane coupling agent attached per unit surface area of the polymer particle surface is 0.05 to 3.0 mg / m ² . A film substrate and a coating formed on the film;
The said coating contains the polymer particle of Claim 15, and a binder, The optical film characterized by the above-mentioned. A coating agent comprising the polymer particles according to claim 15 and a binder. An antiblocking agent comprising the polymer particles according to claim 15. A pore former comprising the polymer particles according to claim 15.