JP6522135B2 - Composite particle, method for producing the same, and use thereof - Google Patents

Description

  The present invention provides a composite particle comprising a polymer particle and a hydrophilic metal oxide particle attached to the surface of the polymer particle, a method for producing the same, and a use thereof (coating agent, optical film resin composition, molded article, And external preparations).

  The polymer particles having an average particle size of 0.01 to 100 μm are, for example, additives for coating agents such as paints (eg, matting agents), additives for ink (eg, matting agents), main components of adhesives Or additives, additives for artificial marble (such as low-shrinkage agents), paper treatment agents, fillers for external preparations such as cosmetics (fillers for improving slipperiness), column fillers used in chromatography, static It is used in applications such as additives for toners used for charge image development, antiblocking agents for films, and light diffusing agents for light diffusers (light diffusing films etc.).

  By the way, in recent years, compounding hydrophilic metal oxide particles such as silica particles with polymer particles is one of the methods for imparting new properties to polymer particles or improving the properties of polymer particles. Is considered. It is thought that the hydrophilicity of the particle surface can be improved by attaching hydrophilic metal oxide particles such as silica particles to the surface of the polymer particles. Since particles having hydrophilicity on the surface are easily dispersed in an aqueous medium, additives for water-based coating agents, for example, light diffusing agents used in water-based coating agents for forming coatings of optical films such as light diffusion films Can be suitably used.

  Patent Document 1 discloses a method for producing composite particles including polymer particles and silica particles attached to the polymer particles, wherein the polymerizability is obtained in the presence of silica particles having a water-soluble cellulose adsorbed on the surface. A method of producing composite particles is described which comprises a polymerization step of aqueous suspension polymerization of monomers to obtain composite particles.

  Further, in Comparative Example 4 of Patent Document 2, a mixture obtained by mixing an emulsion obtained by absorbing a vinyl monomer containing a polymerization initiator into seed particles in an aqueous medium, and colloidal silica, is obtained. There is described a method for producing polymer particles in which the vinyl monomer is polymerized by heating.

International Publication No. 2015/071984 Patent No. 5281781 gazette

  However, since the composite particles produced by the production method described in Patent Document 1 have relatively few surface irregularities derived from silica particles etc., the surface irregularities derived from silica particles etc significantly improve particle fluidity. It is not possible to exert the effect as it does, and there is room for improvement in the particle fluidity (see Comparative Example 5 in the present specification). The particle flowability of the composite particles can be improved by improving the handling of the composite particles when producing a product using the composite particles, for example, an optical film such as a light diffusion film, or in an aqueous dispersion medium such as an aqueous binder. It contributes to the suppression of generation of lumps (lumps formed by aggregation of composite particles).

  Further, according to the study by the inventor of the present application, in the production method of Comparative Example 4 of Patent Document 2, the silica particles contribute as a dispersant, but adhesion to the surface of the polymer particles is scarce (the silica particles It was found that hydrophilicity can not be imparted to the polymer particles, and that the particle fluidity of the polymer particles can not be improved (see Comparative Example 3 of the present specification).

  The present invention has been made in view of such a situation, and has hydrophilicity, and as a result, it is excellent in dispersion stability in an aqueous dispersion medium such as an aqueous binder, and is excellent in particle fluidity. It is an object of the present invention to provide a composite particle and a method for producing the same, and a use thereof.

The composite particle of the present invention is a composite particle including a polymer particle composed of a polymer of a vinyl-based monomer and a hydrophilic metal oxide particle attached to the surface of the polymer particle, and the shape of the composite particle From the volume average particle diameter D (μm) and the density ((g / cm ³ ) of the composite particle, assuming that を is a true sphere, the following equation (calculated value of specific surface area) = 6 / (ρ × D)
Ratio of the calculated specific surface area (m ² / g) to the actual measured value of the specific surface area of the composite particles (m ² / g) obtained by the actual measurement (actual value of the specific surface area) / (Calculated value of specific surface area) is characterized by being 1.20 or more.

  The composite particles of the present invention are hydrophilic due to the hydrophilicity of the hydrophilic metal oxide particles attached to the surface of the polymer particles, and as a result, the dispersion stability in an aqueous dispersion medium such as an aqueous binder is excellent. ing. The improvement of the dispersion stability in the aqueous dispersion medium contributes, for example, to the suppression of the defects generated in the coating (coating film) when the composite particles are mixed with the aqueous binder and used as a coating agent.

  Further, the numerical value of (measured value of specific surface area) / (calculated value of specific surface area) represents how large the specific surface area is with respect to the case of a true sphere, and thus represents the number of surface irregularities. The composite particles of the present invention have a large number of surface irregularities because (measured value of specific surface area) / (calculated value of specific surface area) is 1.20 or more. The composite particles of the present invention are excellent in particle flowability because they have many surface irregularities. The particle flowability of the composite particles can be improved by improving the handling of the composite particles when producing a product using the composite particles, for example, an optical film such as a light diffusion film, or in an aqueous dispersion medium such as an aqueous binder. It contributes to suppression of generation of lumps (lumps formed by aggregation of composite particles) and formation of a good coating by the coating agent containing the aqueous binder.

  The method for producing a composite particle of the present invention is a method for producing a composite particle comprising a polymer particle comprising a polymer of a vinyl-based monomer, and a hydrophilic metal oxide particle attached to the polymer particle, After the vinyl-type monomer is absorbed by the seed particles, the vinyl-type monomer in an aqueous medium is present in the presence of the hydrophilic metal oxide particles in which the water-soluble cellulose is adsorbed on the surface and the reactive surfactant. The method is characterized by including a polymerization step of obtaining composite particles by seed polymerization to be polymerized.

  According to the above method, the vinyl monomer is polymerized in the aqueous medium in the presence of the hydrophilic metal oxide particles on the surface of which the water-soluble cellulose is adsorbed, the water-soluble cellulose and the reactive surfactant. From the above, it is possible to improve the adhesion of the surface of the polymer particle during polymerization by the action of the reactive surfactant and attach more hydrophilic metal oxide particles to the surface of the polymer particle, and also hydrophilicity. The hydrophilic metal oxide particles can be firmly attached to the surface of the polymer particles by the action of the water-soluble celluloses adsorbed on the surface of the metal oxide particles. For this reason, the hydrophilic metal oxide particles attached to the surface of the polymer particles have hydrophilicity, and as a result, they are excellent in the dispersion stability in the aqueous dispersion medium such as the aqueous binder, and the hydrophilic metal oxide Particle flowability is excellent because surface irregularities derived from particle etc. are large (measured value of specific surface area) / (calculated value of specific surface area) is large (eg 1.20 or more) and moreover from the surface of polymer particles Composite particles in which hydrophilic metal oxide particles are less likely to come off can be obtained.

  Further, according to the above-mentioned method, a seed particle is made to absorb a vinyl monomer, and then the seed is polymerized in an aqueous medium in the state where the dispersion stability is improved by a reactive surfactant. Since composite particles are obtained by polymerization, composite particles having a smaller variation coefficient of particle diameter (for example, 15% or less) and high uniformity of particle diameter (monodispersity) can be obtained.

  Furthermore, the coating agent of the present invention is characterized by including the composite particles of the present invention.

  Since the coating agent of the present invention contains the composite particles of the present invention, it can impart light diffusion to the coating (coating film) formed from the coating agent. In addition, when the above-mentioned coating agent contains an aqueous solvent, generation of spoils is caused by the excellent particle fluidity of the composite particles and the hydrophilicity of the hydrophilic metal oxide particles attached to the surface of the polymer particles. Thus, good dispersibility of the composite particles can be obtained. Therefore, the coating agent can form a good coating.

  The optical film of the present invention is an optical film comprising a base film and a coating formed thereon, wherein the coating comprises the composite particles of the present invention.

  The optical film of the present invention has light diffusibility because it contains the composite particle of the present invention.

  According to the present invention, a composite particle having hydrophilicity and, as a result, excellent dispersion stability in an aqueous dispersion medium such as an aqueous binder and the like, and excellent particle flowability, and a method for producing the same, and the same The application can be provided.

1 is a scanning electron microscope (SEM) image showing composite particles obtained in Example 1. 1 is a transmission electron microscope (TEM) image showing a cross section of a composite particle obtained in Example 1. It is a scanning electron microscope (SEM) image which shows the composite particle obtained by the comparative example 1. FIG. It is a figure which shows the infrared absorption spectrum of the extract of the composite particle obtained in Example 1 with the infrared absorption spectrum of hydroxypropyl methylcellulose.

Hereinafter, the present invention will be described in more detail.
[Composite particles]
The composite particle of the present invention is a composite particle including a polymer particle composed of a polymer of a vinyl-based monomer and a hydrophilic metal oxide particle attached to the surface of the polymer particle, and the shape of the composite particle From the volume average particle diameter D (μm) and the density ((g / cm ³ ) of the composite particle, assuming that を is a true sphere, the following equation (calculated value of specific surface area) = 6 / (ρ × D)
Ratio of the calculated specific surface area (m ² / g) to the actual measured value of the specific surface area of the composite particles (m ² / g) obtained by the actual measurement (actual value of the specific surface area) / (Calculated value of specific surface area) is 1.20 or more.

  The (measured value of specific surface area) / (calculated value of specific surface area) is more preferably 1.30 or more, still more preferably 1.40 or more, and most preferably 1.50 or more. preferable. By these, the particle fluidity of composite particles can be further improved. Further, the above (measured value of specific surface area) / (calculated value of specific surface area) is more preferably 50 or less, and still more preferably 40 or less. Composite particles within these ranges are easy to manufacture.

  The composite particles of the present invention exhibit particle fluidity, and the value of the avalanche energy change AE (Avalanche Energy) before and after avalanche is preferably in the range of 10 to 50 kJ / kg. Thereby, composite particles with high particle fluidity can be realized.

  The composite particle of the present invention has a coefficient of variation of particle diameter of 15% or less. Thereby, composite particles with high uniformity in particle diameter can be realized.

  The composite particles of the present invention preferably have a volume average particle size of 1 to 20 μm. Thereby, composite particles suitable for applications such as a coating agent, an optical film, a molded product, a resin composition, and an external preparation which will be described in detail later can be realized.

  In the composite particle of the present invention, it is preferable that at least a part of the polymer particle is coated with a layer composed of a plurality of silica particles.

(Vinyl monomer)
The polymer particles are polymers of vinyl monomers. The vinyl-based monomer is a compound having a group (ethylenically unsaturated group (vinyl group in a broad sense)) containing a polymerizable carbon-carbon double bond (ethylenically unsaturated bond; vinyl bond in a broad sense) .

  The vinyl-based monomer may be a monofunctional vinyl-based monomer having an ethylenically unsaturated group (vinyl group in a broad sense), and two or more ethylenically unsaturated groups (vinyl group in a broad sense) It may be a vinyl-based monomer.

  Examples of the monofunctional vinyl monomer include, for example, α-methylene aliphatic monocarboxylic acid ester; styrene; o-methylstyrene, m-methylstyrene, p-methylstyrene, p-ethylstyrene, 2,4-dimethylstyrene Styrene, p-n-butylstyrene, p-tert-butylstyrene, p-n-hexylstyrene, p-n-octylstyrene, p-n-nonylstyrene, p-n-decylstyrene, p-n-dodecylstyrene Derivatives of styrene such as p-methoxystyrene, p-phenylstyrene, p-chlorostyrene and 3,4-dichlorostyrene; vinyl carboxylates such as vinyl acetate, vinyl propionate and vinyl butyrate; acrylonitrile, acrylamide and the like Acrylic acid derivatives other than acrylic acid esters; methacrylonitrile, methacrylic Methacrylic acid derivatives other than methacrylic acid esters such as amide and the like.

  As the α-methylene aliphatic monocarboxylic acid ester, methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-octyl acrylate, dodecyl acrylate, 2-ethylhexyl acrylate Stearyl acrylate, lauryl acrylate, 2-chloroethyl acrylate, phenyl acrylate, 2- (dimethylamino) ethyl acrylate, 2- (diethylamino) ethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxy acrylate Acrylic esters such as propyl; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-octyl methacrylate, dodecyl methacrylate, 2-ethyl methacrylate Methacrylic acid such as xyl, stearyl methacrylate, lauryl methacrylate, phenyl methacrylate, 2- (dimethylamino) ethyl methacrylate, 2- (diethylamino) ethyl methacrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate and the like Esters and α-haloacrylic acid esters such as methyl α-chloroacrylate and the like can be mentioned.

  In some cases, α, β-unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, fumaric acid and the like can also be used as monofunctional vinyl monomers. Furthermore, two or more of these may be used in combination. And vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinylpyrrole, N-vinylcarbazole, N-vinylindole, An N-vinyl compound such as N-vinyl pyrrolidone and the like; a vinyl naphthalene salt and the like can also be used as a monofunctional vinyl-based monomer in combination of one or two or more species within the range that does not impair the effects of the present invention.

  In the present invention, the above-mentioned monofunctional vinyl monomers may be used alone or in combination of two or more. Further, among the above monofunctional vinyl monomers, styrene, methyl methacrylate and the like are more preferable as the monofunctional vinyl monomer to be used in the present invention since they are inexpensive.

  Examples of the polyfunctional vinyl-based monomers include divinylbenzene; ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate (the number of repeating units is 2 to 10), propylene glycol di (meth) acrylate, and polypropylene glycol di (Meth) acrylate (the number of repeating units is 2 to 10), 1,3-butylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, alkoxylated neopentyl glycol di (meth) acrylate, propoxylated neopentyl Bifunctional alkylene glycol di (meth) acrylates such as glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate hydroxypivalate, dioxane glycol di (meth) acrylate; Dichlorodi (meth) acrylate, hexanediol di (meth) acrylate, alkoxylated hexanediol di (meth) acrylate, cyclohexanediol di (meth) acrylate, dodecanediol di (meth) acrylate, tricyclodecanediol di (meth) acrylate, etc. Bifunctional alkylene diol di (meth) acrylates; ethoxylated (the number of repeating units is 2 to 10) bifunctional ethoxylated bisphenol A di (meth) acrylates such as bisphenol A di (meth) acrylate; trimethylolpropane tri (meth) Trifunctional trimethylol such as acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate and triacryloyloxyethyl phosphate Lopant tri (meth) acrylates; tetrafunctional tetra (meth) acrylates such as pentaerythritol tetra (meth) acrylate and ditrimethylolpropane tetra (meth) acrylate; and hexafunctional dipentaerythritol hexa (such as dipentaerythritol hexa (meth) acrylates (Meth) acrylates; octafunctional pentaerythritol (meth) acrylates such as poly (pentaerythritol) acrylate; trifunctional nitrogen atom-containing cyclic (meth) acrylates such as ethoxylated isocyanurate tri (meth) acrylate Be In the present application, "(meth) acrylate" means methacrylate or acrylate.

  It is preferable that the said vinyl-type monomer contains both a monofunctional vinyl-type monomer and a polyfunctional vinyl-type monomer. Thereby, a favorable crosslinked structure can be formed in a polymer particle, and favorable solvent resistance can be provided to composite particle | grains. The amount of the polyfunctional vinyl monomer used is preferably in the range of 0.5 to 50% by weight, and more preferably in the range of 1 to 40% by weight, based on the total amount of the vinyl monomer used. It is more preferable that As a result, a more favorable crosslinked structure can be formed in the polymer particles, and further excellent solvent resistance can be imparted to the composite particles.

(Hydrophilic metal oxide particles)
In the present application, the term "hydrophilic metal oxide particles" means metal oxide particles that can be dispersed in water, and more specifically, it exhibits hydrophilic behavior when introduced into water and stirred. Metal oxide particles are meant, ie, metal oxide particles dispersed in water, the surface of which is completely wetted by water and thus has a contact angle to water of less than 90 °. Whether the metal oxide particles attached to the surface of the polymer particles in the composite particles are hydrophilic or not is whether sedimentation of the composite particles starts immediately as a result of conducting a hydrophilicity test (see the examples) of the composite particles It can also be confirmed indirectly depending on whether or not it is. The hydrophilic metal oxide particle is not particularly limited as long as it is a metal oxide particle having hydrophilicity (having a number of hydroxyl groups having a degree of exhibiting hydrophilicity), but silica particles and silica other than silica And a composite oxide particle comprising at least one of tin oxide and zinc oxide doped with at least one of phosphorus and antimony.

  As the silica particles, colloidal silica can be preferably used. Examples of the colloidal silica include powdery colloidal silica such as precipitated silica powder and fumed silica powder, and a sol of colloidal silica stably dispersed to a primary particle level in a medium. Among these, colloidal silica sols stably dispersed to the primary particle level in the medium are more suitable for use in the production method of the present invention.

  As the sol of colloidal silica, aqueous silica sol, organosilica sol, etc. can be suitably used. In particular, in the production method of the present invention, since vinyl monomers are polymerized in an aqueous medium, it is most preferable to use aqueous colloidal silica from the viewpoint of dispersion stability of the colloidal silica sol. The silica concentration (solids concentration) in the colloidal silica sol is preferably 5 to 50% by weight, since it is generally commercially available and easily available.

  Commercial products of the colloidal silica include Snowtex (registered trademark) series manufactured by Nissan Chemical Industries, Ltd., for example, general-purpose type Snowtex (registered trademark) (alkaline, which is spherical particles having an average primary particle diameter of 5 to 100 nm) : "ST-XS", "ST-30", "ST-50", "ST-30L", "ST-ZL", acidity: "ST-OXS", "ST-O", "ST-O- 40 "," ST-OL "," ST-OZL 35 "), large particle type Snowtex (registered trademark) having spherical particles with an average primary particle diameter of 70 to 480 nm (alkaline:" ST-MP-2040 "," ST-MP-4540M "), an elongated primary chain particle type Snowtex (registered trademark) having an average primary particle size of 40 to 100 nm (alkaline:" ST-UP ", acidic:" "T-OUP"), pearl necklace-like type Snowtex (registered trademark) in which spherical particles having an average primary particle diameter of 10 to 25 nm are linked (alkaline: "ST-PS-S", "ST-PS-M", Acidic: "ST-PS-SO", "ST-PS-MO") etc. can be mentioned.

  When silica-coated metal oxide particles are used as the hydrophilic metal oxide particles, particularly when the metal oxides other than silica are metal oxides having high photocatalytic activity such as titanium oxide and zinc oxide, silica When silica coating particles of metal oxides other than silica deactivates the photocatalytic activity of metal oxides other than silica, metal oxides other than silica and other components are deteriorated by photocatalytic reaction by ultraviolet light (for example, yellow) Can be effectively suppressed. As a result, it is possible to effectively improve the weather resistance of the composite particle and the product using it.

  The content of silica in the silica-coated metal oxide particles is preferably 10% by weight or more. When the content of silica in the silica-coated metal oxide particles is less than 10% by weight, the effect of suppressing deterioration (for example, yellowing) of composite particles by silica and a product using the same is reduced. The content of silica in the silica-coated metal oxide particles is more preferably 10% by weight or more and 50% by weight or less. When the content of silica in the silica-coated metal oxide particles is more than 50% by weight, imparting of properties (for example, ultraviolet shielding properties) to composite particles by metal oxides other than silica is not remarkable.

  Examples of metal oxides other than silica constituting the silica-coated metal oxide particles include titanium oxide, zinc oxide, cerium oxide, iron oxide, zirconium oxide and the like, and at least one of titanium oxide and zinc oxide is preferable. When the metal oxide other than silica is at least one of titanium oxide and zinc oxide, it can impart excellent ultraviolet shielding properties to the composite particles, and can be suitably used for external preparations such as light diffusion plates and cosmetics. In addition, titanium oxide and zinc oxide have high photocatalytic activity, but in the composite particle of the present invention, titanium oxide and zinc oxide, and other components are obtained by inactivating the photocatalytic activity of titanium oxide and zinc oxide. Deterioration (for example, yellowing) due to photocatalytic reaction by ultraviolet light can be effectively suppressed. As a result, it is possible to improve the weatherability of composite particles containing at least one of titanium oxide and zinc oxide as metal oxides other than silica and products using the same.

  The silica-coated metal oxide particles are at least one of silica-coated titanium oxide particles in which titanium oxide particles are coated with silica and silica-coated zinc oxide particles in which zinc oxide particles are coated with silica preferable. As said silica-coated titanium oxide particle, the commercial item of a silica-coated titanium oxide particle or its water dispersion can be used. As a commercial item of the said silica coating titanium oxide particle | grains or its water dispersion, for example, "Maxlite (trademark) TS-01", "Maxlight (trademark) TS-04", "Maxlight (trademark)" “TS-043”, “Max Light (registered trademark) F-TS 20” (above, made by Showa Denko KK), “MT-100 HP”, “MT-100 WP”, “MT-500 SA”, “WT-PF01” Water dispersion having a solid content of 40% by weight (above, manufactured by Tayca Corporation), “STR-100A”, “STR-100W”, “GT-10W” (water dispersion having a solid content of 40% by weight) (above, 堺Chemical Industry Co., Ltd.), "ST-455WS" (manufactured by Titanium Industry Co., Ltd.) and the like.

  A commercial item of silica-coated zinc oxide particles can be used as the silica-coated zinc oxide particles. Examples of commercially available products of the silica-coated zinc oxide particles include “Maxlight (registered trademark) ZS-032” and “Maxlight (registered trademark) ZS-032-D” (all manufactured by Showa Denko Corporation), Examples include FINEX (registered trademark) -30W and "FINEX (registered trademark) -50W" (all manufactured by Sakai Chemical Industry Co., Ltd.).

  The above-mentioned composite oxide particles comprising at least one of tin oxide and zinc oxide doped with at least one of phosphorus and antimony include, for example, tin oxide doped with phosphorus (phosphorus-doped tin oxide) particles, antimony-doped Zinc oxide particles, mixtures thereof, and the like. Since the material containing antimony is concerned about environmental load, the complex oxide particle may be composed of at least one of phosphorus-doped tin oxide and zinc oxide (for example, phosphorus-doped tin oxide) More preferable. Examples of commercially available products of the phosphorus-doped tin oxide (phosphorus-doped tin oxide) particles include “CELNAX (registered trademark) CX-S301H” (water dispersion, manufactured by Nissan Chemical Industries, Ltd.). Examples of antimony-doped zinc oxide particles include "CELNAX (registered trademark) CX-Z330H" (water dispersion, manufactured by Nissan Chemical Industries, Ltd.).

  The average primary particle diameter of the hydrophilic metal oxide particles is preferably in the range of 5 to 200 nm. When the average primary particle size is larger than 200 nm, the dispersion stability at the time of producing the composite particles is lowered, which is not preferable. The average primary particle diameter of the hydrophilic metal oxide particles is preferably as small as possible, more preferably in the range of 5 to 150 nm, and still more preferably in the range of 8 to 100 nm.

The density (specific gravity) of the hydrophilic metal oxide particles is preferably in the range of 1.5 to 10.0 g / cm ³ . If the density is more than 10.0 g / cm ³ , it is not preferable because the dispersion stability at the time of producing composite particles is lowered.

  Further, the content of the hydrophilic metal oxide particles in the composite particles of the present invention is not particularly limited, but is preferably in the range of 0.5 to 10% by weight. Thus, the hydrophilicity of the composite particles can be further improved, and (the measured value of the specific surface area) / (the calculated value of the specific surface area) can be further increased to further improve the particle fluidity.

(Water soluble celluloses)
The composite particles of the present invention preferably further contain water-soluble celluloses. In this case, since the hydrophilic metal oxide particles are firmly attached to the surface of the polymer particles due to the inclusion of the water-soluble celluloses, the hydrophilic metal oxide particles are less likely to come off from the surface of the polymer particles.

  In the composite particles further containing water-soluble celluloses, the hydrophilic metal oxide particles may be attached to the surface of the polymer particles via the water-soluble celluloses, or on the surface of the polymer particles It may be attached directly. In other words, the water-soluble celluloses may be attached to both the hydrophilic metal oxide particles and the polymer particles, or only to one of the hydrophilic metal oxide particles and the polymer particles. It may be done.

  The water-soluble celluloses are not particularly limited. For example, alkylcelluloses such as methylcellulose; Hydroxyalkylcelluloses such as hydroxymethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose; Hydroxyalkylalkyls such as hydroxyethyl methylcellulose, hydroxypropyl methylcellulose Compounds such as celluloses can be mentioned. Among these compounds, hydroxyalkyl celluloses and hydroxyalkyl alkyl celluloses are preferable, and hydroxypropyl cellulose (HPC) and hydroxypropyl methyl cellulose (HPMC) are more preferable. Also, these compounds may be used alone or in combination of two or more.

  Hydroxypropyl cellulose (HPC) is generally known to have a lower limit critical solution temperature (LCST) of 45 ° C. As a commercial product, for example, NISSO (registered trademark) manufactured by Nippon Soda Co., Ltd. HPC series ("SSL", "SL", "L", "M", "H", etc.) can be mentioned.

  In addition, as a commercially available product of hydroxypropyl methylcellulose (HPMC), the Metrose (registered trademark) series manufactured by Shin-Etsu Chemical Co., Ltd., more specifically, the Metrose (registered trademark) 60 SH series having a cloud point of 60 ° C. (“ SH60-50 "," 60SH-4000 "," 60SH-10000 "), Metros (registered trademark) 65SH series (" 65SH-50 "," 65SH-400 "," 65SH-500 ") having a cloud point of 65 ° C , "65 SH-4000", and Metrose (registered trademark) 90 SH series ("90 SH-100", "90 SH-400", "90 SH-4000", "90 SH-15000") having a cloud point of 90.degree. C., etc. are listed. be able to.

[Method of producing composite particles]
The method for producing a composite particle of the present invention is a method for producing a composite particle comprising a polymer particle comprising a polymer of a vinyl-based monomer, and a hydrophilic metal oxide particle attached to the polymer particle, After the vinyl-type monomer is absorbed by the seed particles, the vinyl-type monomer in an aqueous medium is present in the presence of the hydrophilic metal oxide particles in which the water-soluble cellulose is adsorbed on the surface and the reactive surfactant. The polymerization step is carried out to obtain composite particles by seed polymerization.

(Hydrophilic metal oxide particles with water-soluble cellulose adsorbed on the surface)
The adsorption amount of the water-soluble celluloses to the hydrophilic metal oxide particles is not particularly limited, and can be appropriately set according to the specific surface area of the hydrophilic metal oxide particles used in the present invention, but The amount is preferably 0.05 g to 0.5 g per 1 g of the hydrophilic metal oxide particles.

  In addition, the adsorption amount of water-soluble celluloses to hydrophilic metal oxide particles is, for example, Japanese Journal of Polymer Science and Technology, Vol. 40, no. 10, pp. It can measure using the method described in 697-702 (Oct, 1983). For example, it can be measured by [Method of measuring amount of adsorption of water-soluble cellulose to hydrophilic metal oxide particles] described in the section of Examples described later.

  In the production method of the present invention, before the polymerization step, the hydrophilic metal oxide particles are treated with the water-soluble celluloses to adsorb the water-soluble celluloses onto the surface of the hydrophilic metal oxide particles. It is preferred to include an adsorption step.

  The method for treating the hydrophilic metal oxide particles with the water-soluble celluloses is not particularly limited, and a known method may be used to adsorb the water-soluble celluloses onto the surface of the hydrophilic metal oxide particles. For example, a method of causing hydrophilic metal oxide particles and water-soluble cellulose to coexist in an aqueous medium and physically adsorbing water-soluble cellulose on the surface of the hydrophilic metal oxide particles (as a specific example) Rheological and Interfacial Properties of Silicone Oil Emulsions Prepared by Polymer Pre-adsorbed onto Silica Particles, Colloids Surfaces A: Physicochem. Eng. A pects, 328,2008,114-122 method described in. the literature) are preferred. The water-soluble celluloses adsorbed to the hydrophilic metal oxide particles by this treatment method are in a stable state, hardly desorbing from the hydrophilic metal oxide particles in the polymerization step.

  In addition, the temperature condition of (T-15) ° C (T means the lower limit critical solution temperature (° C) or cloud point (° C) of the water-soluble cellulose) of the water-soluble celluloses is more than that Preferably, by causing the hydrophilic metal oxide particles and the water-soluble cellulose to coexist under the temperature condition of (T-15) ° C. or more and (T + 20) ° C. or less, the hydrophilic metal can be more effective. Water-soluble celluloses can be physically adsorbed on the surface of the oxide particles. The water-soluble celluloses have only one of the lower limit critical solution temperature and the cloud point depending on their properties.

  In the adsorption step, the water-soluble celluloses which are not adsorbed to the hydrophilic metal oxide particles may be removed by centrifugation or the like before the polymerization step, or obtained by the polymerization step after the polymerization step. It may be removed by washing in the purification step of purifying the composite particles.

(Reactive surfactant)
As the reactive surfactant, any of anionic reactive surfactants, cationic reactive surfactants, amphoteric ionic reactive surfactants, and nonionic reactive surfactants can be used. Although it can be used, it is preferable to use a nonionic reactive surfactant. When an anionic reactive surfactant is used as the reactive surfactant, aggregation of hydrophilic metal oxide particles is likely to occur because the reactive surfactant contains metal ions such as sodium ions. As a result, the dispersion stability of the composite particles may be reduced and the uniformity of the particle size of the composite particles may be reduced. When a nonionic reactive surfactant is used as the reactive surfactant, aggregation of the hydrophilic metal oxide particles is less likely to occur because metal ions are not contained in the reactive surfactant. As the dispersion stability of the composite particles is improved, the uniformity of the particle size of the composite particles can be improved.

  Examples of the nonionic reactive surfactants include Adekaria Soap (registered trademark) ER-10 (100 wt.% Pure content) manufactured by ADEKA Corporation, Adekaria Soap (registered trademark) ER-20 (pure composition) 75% by weight) Adekaria soap (registered trademark) ER-30 (65 wt.% Pure, Adekaria soap (registered trademark) ER-40 (60 wt.% Pure), Adekaria soap (registered trademark) NE-10 (Pure weight 100% by weight), Adekaria soap (registered trademark) NE-20 (net weight 80% by weight), Adekaria soap (registered trademark) NE-30 (net weight 80% by weight), and Adekaria soap (registered weight) Trademark: NE-40 (pure 40% by weight); Aqualon (registered trademark) RN-20 (pure 100), which is polyoxyethylene nonylpropenyl phenyl ether manufactured by Daiichi Kogyo Seiyaku Co., Ltd. %), Aqualon® RN-2025 (25% by weight pure), Aqualon® RN-30 (100% by weight pure), and Aqualon® RN-50 (65% by weight pure) Latem® PD-420 (100% by weight pure) which is a polyoxyalkylene alkenyl ether manufactured by Kao Corporation, Latemru® PD-430 (100% by weight pure), and Latemul (100% by weight pure) (Registered trademark) PD-450 (pure 100% by weight), etc. The above-mentioned reactive surfactants may be used alone or in combination of two or more.

  The type of the reactive surfactant is appropriately selected in consideration of the diameter of the composite particle to be obtained, the dispersion stability of the vinyl monomer at the time of polymerization, and the like, and the amount used is appropriately adjusted. The amount of the reactive surfactant used is preferably in the range of 0.01 to 5 parts by weight, preferably 0.1 to 2.0 parts by weight, with respect to 100 parts by weight of the vinyl monomer. It is more preferable that it is inside. When the amount of the reactive surfactant used is smaller than the above range, the polymerization stability may be lowered. In addition, when the amount of the reactive surfactant used is larger than the above range, the cost of the reactive surfactant is deteriorated.

(Non-reactive surfactant)
In the polymerization step of the production method of the present invention, the polymerization of the vinyl monomer in the aqueous medium may be carried out in the presence of a non-reactive surfactant in order to further improve the dispersion stability. . Examples of the non-reactive surfactant include an anionic non-reactive surfactant, a cationic non-reactive surfactant, an amphoteric non-reactive surfactant and a nonionic non-reactive surfactant. In the case of using a nonionic reactive surfactant as the reactive surfactant, an anionic nonreactive surfactant may be used as the nonreactive surfactant. It is preferred to use.

  Non-Reactive Surfactant Reactive Surfactant The reactive surfactant includes, for example, sodium oleate; fatty acid soap such as castor oil potassium soap; alkyl sulfate ester salt such as sodium lauryl sulfate and ammonium lauryl sulfate; sodium dodecyl benzene sulfonate Alkyl benzene sulfonates such as: alkyl naphthalene sulfonates; alkane sulfonates; dialkyl sulfosuccinates such as sodium dioctyl sulfosuccinate; alkyl phosphate ester salts; naphthalene sulfonic acid formalin condensates; polyoxyethylene alkyl phenyl ether sulfates Salts; polyoxyethylene alkyl sulfate ester salts and the like.

  As the nonionic non-reactive surfactant, for example, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid ester, polyoxyethylene alkylamine, glycerin Fatty acid ester, oxyethylene-oxypropylene block polymer etc. are mentioned.

  Examples of cationic non-reactive surfactants include alkylamine salts such as laurylamine acetate and stearylamine acetate; and quaternary ammonium salts such as lauryltrimethylammonium chloride.

  Examples of the zwitterionic non-reactive surfactant include lauryl dimethyl amine oxide, phosphate ester surfactants, phosphite ester surfactants and the like. These non-reactive surfactants may be used alone or in combination of two or more.

  The type of the non-reactive surfactant is appropriately selected in consideration of the diameter of the composite particle to be obtained, the dispersion stability of the vinyl monomer at the time of polymerization, and the like, and the amount used is appropriately adjusted. The amount of the non-reactive surfactant used is preferably in the range of 0.01 to 5 parts by weight with respect to 100 parts by weight of the vinyl monomer. When the amount of non-reactive surfactant used is smaller than the above range, the polymerization stability may be lowered. When the amount of non-reactive surfactant used is larger than the above range, the cost of the non-reactive surfactant is deteriorated.

(Aqueous medium)
Examples of the aqueous medium used in the polymerization step of the production method of the present invention include water or a mixed medium of water and a water-soluble medium (for example, an alcohol such as methanol or ethanol). The amount of the aqueous medium used is preferably 100 to 1000 parts by weight with respect to 100 parts by weight of the vinyl-based monomer in order to stabilize the composite particles.

(Polymerization initiator)
In the polymerization step of the production method of the present invention, the polymerization of the vinyl monomer in the aqueous medium is preferably performed in the presence of a polymerization initiator.

  As the polymerization initiator, an oil-soluble peroxide-based polymerization initiator or an azo-based polymerization initiator generally used for polymerization in an aqueous medium can be suitably used.

  Examples of the peroxide-based polymerization initiator include benzoyl peroxide, lauroyl peroxide, octanoyl peroxide, orthochlorobenzoyl peroxide, orthomethoxybenzoyl peroxide, methyl ethyl ketone peroxide, diisopropyl peroxydicarbonate, and cumene hydroperoxide. And cyclohexanone peroxide, t-butyl hydroperoxide, diisopropylbenzene hydroperoxide and the like.

  Examples of the azo polymerization initiator include, for example, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), and 2,2′-azobis (2,3-) Dimethylbutyronitrile), 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (2,3,3-trimethylbutyronitrile), 2,2'-azobis (2-isopropyl) Butyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), (2-carbamoylazo) isobutyronitrile , 4,4'-azobis (4-cyanovaleric acid), dimethyl-2,2'-azobisisobutyrate and the like.

  Among the above-mentioned polymerization initiators, from the viewpoint of decomposition rate etc., 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitrile), benzoyl peroxide, peroxide Lauroyl is preferred as a polymerization initiator which can be used in the process of the present invention.

  The amount of the polymerization initiator used is preferably 0.01 to 10 parts by weight, and 0.1 to 5.0 parts by weight with respect to 100 parts by weight of the vinyl monomer used. Is more preferred. When the amount of the polymerization initiator used is less than 0.01 parts by weight with respect to 100 parts by weight of the vinyl monomer, it is difficult to sufficiently perform the function of initiating polymerization, and 10 parts by weight Is not preferable because the effect corresponding to the amount used can not be obtained and the cost is uneconomical.

  The polymerization initiator may be mixed with the vinyl monomer, and then the obtained mixture may be dispersed in an aqueous medium, or both of the polymerization initiator and the vinyl monomer may be separately made aqueous. What was disperse | distributed to the medium may be mixed.

(Polymerization inhibitor)
In the polymerization step of the production method of the present invention, the polymerization of the vinyl monomer in the aqueous medium is water soluble in order to suppress the generation of emulsified particles (polymer particles having too small a particle diameter) in an aqueous system. It may be carried out in the presence of a polymerization inhibitor of

  Examples of the water-soluble polymerization inhibitor include nitrites, sulfites, hydroquinones, ascorbic acids, water-soluble vitamin Bs, citric acid, polyphenols and the like. It is preferable that the addition amount of the said polymerization inhibitor exists in the range of 0.02-0.2 weight part with respect to 100 weight part of vinyl monomers for seed polymerization.

(Other additives)
In the polymerization step of the production method of the present invention, the polymerization of the vinyl monomer in the aqueous medium does not impair the effects of the present invention, and other additives such as pigments, dyes, antioxidants , And may be performed in the presence of a UV absorber and the like.

  Examples of the pigment include inorganic pigments such as lead white, red lead, yellow lead, carbon black, ultramarine blue, zinc oxide, cobalt oxide, titanium dioxide, iron oxide, titanium yellow, titanium black, etc .; navels yellow, naphthol yellow S Yellow pigments such as Hansa yellow 10G, benzidine yellow G, benzidine yellow GR, quinoline yellow lake, permanent yellow NCG, tartrazine lake, etc .; orange pigments such as molybdenum orange, permanent orange RK, benzidine orange G, indanth brilliant orange GK, etc. Permanent red 4R, resole red, pyrazolone, red 4R, watching red calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, alizarin lake, brilia Red pigments such as tocarmine B etc .; purple pigments such as fast violet B, methyl violet lake, dioxane violet etc .; alkali blue lake, victoria blue lake, phthalocyanine blue, metal free phthalocyanine blue, phthalocyanine blue partial chloride; fast sky blue, indance Blue pigments such as Ren Blue BC; green pigments such as pigment green B, malachite green lake, and fanal yellow green G; isoindolinone pigments, quinacridone pigments, perinone pigments, perylene pigments, insoluble azo pigments, soluble azo pigments, dyed lakes Organic pigments such as pigments can be mentioned.

  Examples of the dye include nitroso dyes, nitro dyes, azo dyes, stilbene azo dyes, diphenylmethane dyes, triphenylmethane dyes, xanthene dyes, acridine dyes, quinoline dyes, methine dyes, polymethine dyes, thiazole dyes, indamine dyes, Phenol dyes, azine dyes, oxazine dyes, thiazine dyes, sulfur dyes and the like can be mentioned.

  Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol (BHT) and n-octadecyl-3 ′-(3 ′, 5′-di-t-butyl-4′-hydroxyphenyl ) Propionate, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-tert-butyl-4- 4 Hydroxybenzyl) isocyanurate, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 3,9-bis [2- {3- (3-t-Butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-pheno such as tetraoxaspiro [5.5] undecane -Based antioxidants; distearyl pentaerythritol diphosphite, tris (2,4-di-t-butylphenyl) phosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, tetrakis (2,4-di-t-butylphenyl) 4,4′-biphenylene diphosphonite, bis (2-t-butyl-4-methylphenyl) pentaerythritol diphosphite, 2,4,8,10- Phosphorus such as tetra-t-butyl-6- [3- (3-methyl-4-hydroxy-5-t-butylphenyl) propoxy] dibenzo [d, f] [1,3,2] dioxaphosphepin Antioxidants: phenyl-1-naphthylamine, octylated diphenylamine, 4,4-bis (α, α-dimethylbenzyl) diphenylamine N, can be mentioned N'- di-2-naphthyl -p- amine antioxidants such as phenylenediamine.

  Examples of the UV absorber include benzophenone UV absorbers, benzotriazole UV absorbers (for example, "ADEKA STAB (registered trademark) LA-31" manufactured by ADEKA Co., Ltd.), hydroxyphenyl triazine UV absorbers, and the like. .

(Method of polymerization)
In seed polymerization, seed particles are added to an emulsion containing the vinyl monomer and an aqueous medium. The above emulsion can be prepared by a known method. For example, adding a vinyl-based monomer and a reactive surfactant (and a non-reactive surfactant) to an aqueous medium and dispersing with a homogenizer, a sonicator, a micro-emulsifier such as Nanomizer (registered trademark), etc. Thus, an emulsion can be obtained.

  The seed particles may be added to the emulsion as it is, or may be added to the emulsion in the form of being dispersed in an aqueous medium. After the seed particles are added to the emulsion, the vinyl-based 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 addition, the emulsion may be heated to about 30 to 50 ° C. in order to promote absorption of the vinyl-based monomer to the seed particles.

  The seed particles swell by absorbing the vinyl monomer. The mixing ratio of the vinyl-based monomer to the seed particles is preferably such that the vinyl-based monomer for seed polymerization is in the range of 5 to 300 parts by weight with respect to 1 part by weight of the seed particles, More preferably, it is in the range of 250 parts by weight. When the mixing ratio of the vinyl-based monomer is smaller than the above range, the increase in particle size due to polymerization is reduced, and the production efficiency is reduced. On the other hand, when the mixing ratio of the vinyl-based monomer for seed polymerization to be absorbed is larger than the above range, the vinyl-based monomer for seed polymerization is not completely absorbed by the seed particles, and the emulsion polymerization is independently performed in the aqueous medium. As a result, polymer particles with an unusually small particle size may be produced. In addition, completion | finish of absorption of the vinyl-type monomer to seed particle | grain can be determined by confirming expansion of a particle diameter by observation of an optical microscope.

  When the particle diameter of the vinyl monomer droplet existing in the obtained emulsion is smaller than the particle diameter of the seed particle, the vinyl monomer is efficiently absorbed by the seed particle. So preferred.

  And the composite particle which concerns on this invention can be obtained by polymerizing the vinyl-type monomer absorbed by the seed particle.

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

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

  Thus, the composite particles obtained by polymerizing the vinyl-based monomer absorbed by the seed particles are removed from the aqueous medium by filtration, centrifugation, etc. as necessary after the polymerization is completed, and water and After being washed with a solvent, it is dried and isolated. Although the drying method is not particularly limited, for example, a spray drying method represented by a spray dryer, a method of adhering to a heated rotating drum represented by a drum dryer and drying, a method such as a lyophilization method Can be mentioned.

(Seed particle)
The seed particles are polymers of vinyl monomers for the seed particles. The vinyl-based monomer for seed particles may be the same as or different from the vinyl-based monomer used for seed polymerization.

  The polymerization method for polymerizing the vinyl-based monomer for seed particles to obtain seed particles is not particularly limited, but dispersion polymerization, emulsion polymerization, soap-free emulsion polymerization, seed polymerization, suspension polymerization Etc. can be used. In order to obtain polymer particles having a substantially uniform particle size by seed polymerization, it is necessary to use seed particles having a substantially uniform particle size and to grow these seed particles approximately uniformly. The seed particles having a substantially uniform particle size, which is a raw material, are produced by polymerizing vinyl monomers for the seed particles by a polymerization method such as soap-free emulsion polymerization (emulsion polymerization without using a surfactant) and dispersion polymerization. can do. Therefore, as a polymerization method for obtaining seed particles, emulsion polymerization, soap-free emulsion polymerization, seed polymerization and dispersion polymerization are preferable.

  A polymerization initiator is also used in the polymerization of the vinyl-based monomer for the seed particle to obtain the seed particle, if necessary. Examples of the polymerization initiator include persulfates such as potassium persulfate, ammonium persulfate, sodium persulfate, potassium persulfate and the like; benzoyl peroxide, lauroyl peroxide, o-chlorobenzoyl peroxide, o-methoxyperoxide Organic peroxides such as benzoyl, 3,5,5-trimethylhexanoyl peroxide, tert-butylperoxy-2-ethylhexanoate, di-tert-butylperoxide, etc .; Examples include azo compounds such as ronitrile, 1,1′-azobiscyclohexanecarbonitrile, 2,2′-azobis (2,4-dimethylvaleronitrile) and the like. 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 for seed polymerization. The weight average molecular weight of the obtained seed particles 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 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 dimers; terpenes such as γ-terpinene and dipentene; halogenated hydrocarbons such as chloroform and carbon tetrachloride Can be used. The weight average molecular weight of the obtained seed particles can be adjusted by adjusting the amount of the molecular weight modifier used.

  The seed particle uses the seed particle as a primary seed particle, makes the primary seed particle absorb a vinyl monomer, and then polymerizes the vinyl monomer in an aqueous medium one or more times of seed polymerization Seed particles obtained by carrying out (secondary seed particles when obtained by carrying out a single seed polymerization) may be used. This seed polymerization is similar to the seed polymerization for obtaining composite particles except that hydrophilic metal oxide particles, water-soluble celluloses and reactive surfactants are not required.

〔Coating agent〕
The composite particles of the present invention can be contained in a coating agent as a coating (softening) softener, a paint matting agent, a light diffusing agent and the like. The coating agent of the present invention contains the composite particles of the present invention.

  The coating agent optionally contains a binder resin. As the binder resin, an organic solvent or a resin soluble in water, or an emulsion-type aqueous resin that can be dispersed in water can be used, and any known binder resin can be used. As the binder resin, for example, a product manufactured by Mitsubishi Rayon Co., Ltd. under the trade name "Dianal (registered trademark) LR-102" or "Dianal (registered trademark) BR-106", or a product manufactured by Dainichi Seika Kogyo Co., Ltd. Acrylic resin such as “medium VM”; alkyd resin; polyester resin; polyurethane resin such as “E-5221P” manufactured by Daido Chemical Industries, Ltd .; chlorinated polyolefin resin; amorphous polyolefin resin; silicone resin etc. Be These binder resins may be appropriately selected depending on the adhesion of the coating agent to the substrate to be coated, the environment to be used, and the like.

  The compounding amount of the composite particles is appropriately adjusted according to the thickness of the coating (coating film) formed by the coating agent containing the binder resin, the average particle diameter of the composite particles, the coating method, the use to be used, etc. It is preferably in the range of 1 to 300 parts by weight, and more preferably in the range of 5 to 100 parts by weight with respect to the parts by weight. When the compounding amount of the composite particles is less than 1 part by weight with respect to 100 parts by weight of the binder resin, the matting effect may not be sufficiently obtained. In addition, if the compounding amount of the composite particles exceeds 300 parts by weight with respect to 100 parts by weight of the binder resin, the viscosity of the coating agent may become too high, which may cause dispersion failure of the composite particles. Poor appearance of the coating (coating film) surface, such as micro cracks occurring on the surface of the coating (coating film) obtained by coating the coating agent, or roughness on the surface of the resulting coating (coating film), etc. It can happen.

  The coating agent optionally contains a medium. It is preferable to use, as the medium, a solvent (solvent) capable of dissolving the binder resin, or a dispersion medium capable of dispersing the binder resin. Both an aqueous medium and an oily medium can be used as the dispersion medium or solvent. Examples of oily media include hydrocarbon solvents such as toluene, xylene and cyclohexane; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; ester solvents such as ethyl acetate and butyl acetate; dioxane, ethylene glycol diethyl ether, ethylene glycol mono Ether solvents such as butyl ether may, for example, be mentioned. Aqueous media include water, alcohols (eg, isopropanol), and the like. These media may be used alone or in combination of two or more. The content of the medium in the coating agent is usually in the range of 20 to 60% by weight based on the total amount of the coating agent.

  Furthermore, as the coating agent, a curing agent, a coloring agent (body pigment, color pigment, metal pigment, mica powder pigment, dye, etc.), an antistatic agent, a leveling agent, a fluidity regulator, an ultraviolet light absorber, a light stabilizer, etc. And other additives may be included.

  It does not specifically limit as a to-be-coated base material of a coating agent, The base material according to a use can be used.

  For example, in optical applications, a glass substrate, a transparent substrate made of a transparent substrate resin, and the like are used as a substrate to be coated. A light diffusing film or a light diffusing film is formed by using a transparent substrate as a substrate to be coated and coating a colorant-free coating agent (coating agent for light diffusion) on the transparent substrate to form a transparent coating film. An optical film such as an antiglare film can be produced. In this case, the composite particles function as a light diffusing agent.

  Moreover, a matte paper can be manufactured by using paper as a to-be-coated base material, and coating the coating agent (coating agent for paper) which does not contain a coloring agent, and forming a transparent coating film.

  The coating method of the coating agent is not particularly limited, and any known method can be used. Examples of the coating method include comma direct method, spin coating method, spray coating method, roll coating method, dipping method, knife coating method, curtain flow method, laminating method and the like. The coating agent may be diluted with a diluent to adjust the viscosity as needed. Diluents include hydrocarbon solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; ester solvents such as ethyl acetate and butyl acetate; ether solvents such as dioxane and ethylene glycol diethyl ether; water Alcohol solvents and the like can be mentioned. These diluents may be used alone or in combination of two or more. When manufacturing an optical film, it is preferable to use the method in which the unevenness | corrugation originating in composite particle | grains is formed in a coating-film surface as a coating method.

  Since the coating agent of the present invention contains the composite particles of the present invention, it can impart light diffusion to the coating (coating film) formed from the coating agent. Further, in the above-mentioned coating agent, the hardness of the composite particles is ensured by the hydrophilic metal oxide particles adhering to the surface of the polymer particles, so that the scratch resistance of the coating (coating film) formed from the coating agent is improved. Can be expected. In addition, when the above-mentioned coating agent contains an aqueous solvent, generation of spoils is caused by the excellent particle fluidity of the composite particles and the hydrophilicity of the hydrophilic metal oxide particles attached to the surface of the polymer particles. Thus, good dispersibility of the composite particles can be obtained. Therefore, the coating agent can form a good coating.

[Optical film]
The optical film of the present invention is an optical film comprising a substrate film and a coating formed thereon, wherein the coating comprises the composite particles of the present invention. The optical film of the present invention can be produced by a method of applying the coating agent of the present invention on a substrate film to form a coating (coated film). As a specific example of an optical film, a light-diffusion film, an anti-glare film, etc. can be mentioned.

  As a specific example of the constituent material of the said base film, glass, transparent resin, etc. can be mentioned. Examples of the transparent resin include acrylic resin such as polymethyl methacrylate, alkyl (meth) acrylate-styrene copolymer, polycarbonate, polyester such as polyethylene terephthalate (hereinafter abbreviated as "PET"), polyethylene, polypropylene, polystyrene Etc. Among these transparent resins, acrylic resins, alkyl (meth) acrylate-styrene copolymers, polycarbonates, polyesters, and polystyrenes are preferable when excellent transparency is required for the transparent resins. These transparent resins can be used alone or in combination of two or more.

  The thickness of the coating is preferably in the range of 5 to 100 μm.

[Resin composition]
The composite particles of the present invention can be used in a resin composition containing a base resin. The resin composition of the present invention contains the composite particles of the present invention and a base resin. The resin composition contains the composite particles of the present invention, and is excellent in light diffusibility, so that a light cover (a light cover for light emitting diode (LED) lighting, a light cover for fluorescent lamp lighting, etc.), a light diffusion sheet, light diffusion It can be used as a raw material of light diffusers such as plates.

  As the base resin, usually, a thermoplastic resin different from the component of the polymer constituting the composite particles is used. Examples of the thermoplastic resin used as the base resin include (meth) acrylic resin, alkyl (meth) acrylate-styrene copolymer, polycarbonate, polyester, polyethylene, polypropylene, polystyrene and the like. Among these thermoplastic resins, acrylic resins, alkyl (meth) acrylate-styrene copolymers, polycarbonates, polyesters, and polystyrenes are preferable when excellent transparency is required for the base resin. These thermoplastic resins can be used alone or in combination of two or more.

  The addition ratio of the composite particles to the base resin is preferably in the range of 0.1 to 70 parts by weight and preferably in the range of 1 to 50 parts by weight with respect to 100 parts by weight of the base resin. Is more preferred. When the addition ratio of the composite particles to the base resin is less than 0.1 parts by weight with respect to 100 parts by weight of the base resin, it may be difficult to give the light diffuser a light diffusing property. When the addition ratio of the composite particles to the base resin is more than 70 parts by weight with respect to 100 parts by weight of the base resin, the above-described light diffuser can be provided with light diffusivity but the light transmission of the light diffuser The sex may be low.

  The method for producing the resin composition is not particularly limited, and the resin composition can be produced by mixing the composite particles and the base resin according to a conventionally known method such as a mechanical grinding and mixing method. In the mechanical pulverizing and mixing method, for example, a resin composition is obtained by mixing and stirring the composite particles and the base resin using an apparatus such as a Henschel mixer, a V-type mixer, a tabra mixer, a hybridizer, a rocking mixer and the like. Can be manufactured.

[Molded body]
The resin composition of the present invention can be molded into a molded body. The molded article of the present invention comprises the resin composition of the present invention. Specific examples of the molded body include light diffusers such as a light cover (a light cover for light emitting diode (LED) lighting, a light cover for fluorescent lamp lighting, etc.), a light diffusion sheet, a light diffusion plate and the like.

  For example, after the composite particles and the base resin are mixed by a mixer and kneaded by a melt kneader such as an extruder to obtain pellets comprising the resin composition, the pellets are extruded or formed, or the pellets After melting, it is possible to obtain a molded product of any shape by injection molding.

[External use agent]
The composite particle of the present invention is an external use agent as an additive for improving the feeling of use such as slippery, or an additive for making the skin defects such as pores, spots and wrinkles inconspicuous by the light diffusion effect. Can be contained in The external preparation contains the composite particle of the present invention. When the external preparation is a liquid external preparation such as a lotion or the like, the redispersibility of the composite particles is extremely good, and the feeling in use is excellent.

  The content of the composite particles in the external preparation can be appropriately set according to the type of external preparation, but is preferably in the range of 1 to 80% by weight, and more preferably in the range of 3 to 70% by weight preferable. When the content of the composite particles with respect to the total amount of the external preparation is less than 1% by weight, a clear effect due to the content of the composite particles may not be recognized. In addition, when the content of the composite particles exceeds 80% by weight, a remarkable effect commensurate with the increase in the content may not be recognized, which is not preferable in terms of production cost.

  The external preparation can be used, for example, as an external medicine, a cosmetic and the like. The external preparation is not particularly limited as long as it is applied to the skin, and specific examples include creams, ointments, emulsions and the like. Examples of cosmetics include cosmetics for cleaning soaps, body shampoos, face wash creams, scrub face cleansers, toothpastes, etc .; powders, face powders (loose powder, pressed powder, etc.), foundations (powder foundation, liquid foundation, emulsion type) Foundations etc.), lipsticks, lip balms, blushers, eye cosmetics, eye shadows, eyeliners, mascaras etc., manicures etc. makeup cosmetics; pre-shave lotions, body lotions etc. body powders, baby powders etc. Skin care agents such as lotions, creams, emulsions (cosmetic emulsions), antiperspirants (liquid antiperspirants, solid antiperspirants, cream antiperspirants etc.), packs, hair wash cosmetics, dyes Hair, hair setting, aromatic cosmetics, bath preparation, day Only protection products, suntan products, include the shaving cream and the like.

  The composite particles to be blended in the external preparation may be treated with a surface treatment agent such as oil agent, silicone compound and fluorine compound, organic powder, inorganic powder and the like.

  The oil agent may be any one generally used for external preparations, for example, hydrocarbon oil such as liquid paraffin, squalane, vaseline, paraffin wax; lauric acid, myristic acid, palmitic acid, stearic acid, olein Higher fatty acids such as acid, behenic acid, undecylenic acid, oxystearic acid, linoleic acid, lanolin fatty acid, synthetic fatty acids; glyceryl trioctanoate, propylene glycol dicaprate, cetyl 2-ethylhexanoate, ester oils such as isocetyl stearate; , Waxes such as persimmon wax, lanolin, carnauba wax, candelilla wax; Oils such as linseed oil, cottonseed oil, castor oil, egg yolk oil, coconut oil etc. Metal soaps such as zinc stearate, zinc laurate etc; cetyl alcohol, stearyl Alcohol, oleyla Higher alcohols such as call, and the like. Further, the method of treating the composite particles with the above-mentioned oil agent is not particularly limited, but, for example, a dry method of adding an oil agent to the composite particles and coating the oil agent by stirring with a mixer etc. After heating and dissolving in a suitable solvent such as hexane, and adding composite particles thereto and stirring them, the solvent may be removed under reduced pressure or removed by heating to use a wet method of coating an oil agent.

  Any silicone compound may be used as the silicone compound as long as it is generally used for external preparations, and examples thereof include dimethylpolysiloxane, methylhydrogenpolysiloxane, methylphenylpolysiloxane, acrylic-silicone graft polymer, and partial cross-linking of organic silicone resin. Type organopolysiloxane polymers and the like. The method for treating the composite particles with the silicone compound is not particularly limited, and for example, the above-mentioned dry method or wet method can be used. If necessary, a baking treatment may be carried out, or in the case of a reactive silicone compound, a reaction catalyst may be added as appropriate.

  The fluorine compound may be any compound as long as it is usually blended in an external preparation, and examples thereof include perfluoroalkyl group-containing esters, perfluoroalkylsilanes, perfluoropolyethers, polymers having perfluoro groups, and the like. The method for treating the composite particles with a fluorine compound is not particularly limited, but, for example, the above-mentioned dry method or wet method can be used. In addition, if necessary, a baking treatment may be performed, or in the case of a reactive fluorine compound, a reaction catalyst or the like may be added as appropriate.

  Examples of the organic powder include natural polymer compounds such as gum arabic, tragacanth gum, guar gum, locust bean gum, karaya gum, iris moss, quince seed, gelatin, shellac, rosin, casein, etc .; sodium carboxymethylcellulose, hydroxyethylcellulose, methylcellulose, Semi-synthetic polymer compounds such as ethyl cellulose, sodium alginate, ester gum, nitrocellulose, hydroxypropyl cellulose, crystalline cellulose; polyvinyl alcohol, polyvinyl pyrrolidone, sodium polyacrylate, carboxyvinyl polymer, polyvinyl methyl ether, polyamide resin, silicone oil, Nylon particles, polymethyl methacrylate particles, crosslinked polystyrene particles, silicone particles, urethane particles, poly Styrene particles include resin particles such as fluorine resin particles. Moreover, as the inorganic powder, for example, iron oxide, ultramarine, conjo, chromium oxide, chromium hydroxide, carbon black, manganese violet, titanium oxide, zinc oxide, talc, kaolin, mica, calcium carbonate, magnesium carbonate, silicic acid Aluminum, barium silicate, calcium silicate, magnesium silicate, silica, zeolite, barium sulfate, calcined calcium sulfate (gypsum gypsum), calcium phosphate, hydroxyapatite, ceramic powder and the like can be mentioned. In addition, these organic powders and inorganic powders may be subjected to surface treatment in advance. As the surface treatment method, known surface treatment techniques as described above can be used.

  Moreover, the main agent or additive generally used can be mix | blended with the said external preparation in the range which does not impair the effect of this invention according to the objective. As such main agent or additive, for example, water, lower alcohol (alcohol having 5 or less carbon atoms), fats and oils and waxes, hydrocarbon, higher fatty acid, higher alcohol, sterol, fatty acid ester, metal soap, moisturizing agent, Surfactants, polymer compounds, coloring materials, perfumes, clay minerals, preservatives / bactericidal agents, anti-inflammatory agents, antioxidants, UV absorbers, organic-inorganic composite particles, pH adjusters (such as triethanolamine), Specific compounded additives, active pharmaceutical ingredients, etc. may be mentioned.

  Specific examples of the fats and oils and waxes are avocado oil, almond oil, olive oil, cacao butter, beef tallow, sesame oil, wheat germ oil, safflower oil, shea butter, turtle oil, soy sauce, parsic oil, castor oil, grape oil , Macadamia nut oil, mink oil, egg yolk oil, rice bran oil, coconut oil, rosehip oil, hydrogenated oil, silicone oil, orange raffe oil, carnauba wax, candelilla wax, persimmon wax, jojoba oil, montan wax, beeswax, lanolin etc. Be

  Specific examples of the hydrocarbon include liquid paraffin, petrolatum, paraffin, ceresin, microcrystalline wax, squalane and the like.

  Specific examples of the higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, undecylenic acid, oxystearic acid, linoleic acid, lanolin fatty acid, fatty acid having 11 or more carbon atoms such as synthetic fatty acid Can be mentioned.

  Specific examples of the higher alcohol include lauryl alcohol, cetyl alcohol, cetostearyl alcohol, stearyl alcohol, oleyl alcohol, behenyl alcohol, lanolin alcohol, hydrogenated lanolin alcohol, hexyl decanol, octyl decanol, isostearyl alcohol, jojoba alcohol. And alcohols having 6 or more carbon atoms such as decyl tetradecanol.

  Specific examples of the sterols include cholesterol, dihydrocholesterol, phytocholesterol and the like.

  Specific examples of the fatty acid ester include linoleic acid esters such as ethyl linoleate; lanolin fatty acid esters such as lanolin fatty acid isopropyl; lauric acid esters such as hexyl laurate; isopropyl myristate, myristyl myristate, cetyl myristate, myristic acid Myristic acid esters such as octyl decyl and octyl dodecyl myristate; oleic acid esters such as decyl oleate and octyl dodecyl oleate; dimethyl octanoate such as hexyl decyl dimethyl octanoate; cetyl isooctanoate (cetyl 2-ethylhexanoate) Isooctanoic acid esters such as decyl palmitate, etc .; palmitic acid esters such as decyl palmitate; glycerin trimyristate, tri (caprylic capric acid) glycerin, propylene dioleate Glycol, triisostearate glycerin, triisooctanoate glycerin, cetyl lactate, myristyl lactate, diisostearyl malate, cholesteryl isostearate, cyclic alcohol fatty acid esters such as 12-hydroxystearic acid cholesteryl, and the like.

  Specific examples of the metal soap include zinc laurate, zinc myristate, magnesium myristate, zinc palmitate, zinc stearate, aluminum stearate, calcium stearate, magnesium stearate, zinc undecylenate and the like.

  Specific examples of the humectant include glycerin, propylene glycol, 1,3-butylene glycol, polyethylene glycol, sodium dl-pyrrolidonecarboxylate, sodium lactate, sorbitol, sodium hyaluronate, polyglycerin, xylitol, maltitol and the like. Be

  Specific examples of the surfactant include anionic surfactants such as higher fatty acid soaps, higher alcohol sulfates, N-acyl glutamates and phosphates; and cationic interfaces such as amines and quaternary ammonium salts Activators; Amphoteric surfactants such as betaine type, amino acid type, imidazoline type, lecithin; fatty acid monoglycerides, polyethylene glycol, propylene glycol fatty acid esters, sorbitan fatty acid esters (eg, sorbitan isostearate etc.), sucrose fatty acid esters, polyglycerin fatty acids Nonionic surfactants such as esters and ethylene oxide condensates can be mentioned.

  Specific examples of the polymer compound include natural polymer compounds such as gum arabic, tragacanth gum, guar gum, locust bean gum, karaya gum, iris moss, quince seed, gelatin, shellac, rosin, casein, etc .; sodium carboxymethylcellulose, hydroxyethyl cellulose, Semi-synthetic polymer compounds such as methyl cellulose, ethyl cellulose, sodium alginate, ester gum, nitrocellulose, hydroxypropyl cellulose, crystalline cellulose; polyvinyl alcohol, polyvinyl pyrrolidone, sodium polyacrylate, carboxyvinyl polymer, polyvinyl methyl ether, polyamide resin, silicone Oil, nylon particles, poly (meth) acrylate particles (eg, polymethyl methacrylate particles), Styrene particles, silicone particles, urethane particles, synthetic polymer compounds such as resin particles and polyethylene particles. In the present application, "(meth) acrylic" means methacryl or acrylic.

  Specific examples of the color material include iron oxide (red iron oxide, yellow iron oxide, black iron oxide, etc.), ultramarine blue, conjo, chromium oxide, chromium hydroxide, carbon black, manganese violet, titanium oxide, zinc oxide, Talc, kaolin, calcium carbonate, magnesium carbonate, mica, aluminum silicate, barium silicate, calcium silicate, magnesium silicate, silica, zeolite, barium sulfate, calcined calcium sulfate (gypsum gypsum), calcium phosphate, hydroxyapatite, ceramic powder And inorganic pigments such as azo dyes, nitro dyes, nitroso dyes, xanthene dyes, quinoline dyes, anthraquinoline dyes, indigo dyes, triphenylmethane dyes, phthalocyanine dyes, and pyrene dyes such as pyrene dyes.

  In addition, the powder raw materials such as the powder raw material of the above-described high molecular compound and the raw material of the color material can be used those which have been subjected to surface treatment in advance. As a method of surface treatment, known surface treatment techniques can be used. For example, oil agent treatment with hydrocarbon oil, ester oil, lanolin, etc., silicone treatment with dimethylpolysiloxane, methylhydrogenpolysiloxane, methylphenylpolysiloxane etc., Treatment of fluorine compounds with perfluoroalkyl group-containing esters, perfluoroalkylsilanes, perfluoropolyethers and polymers having perfluoroalkyl groups, 3-methacryloxypropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, etc. Coupling agent treatment by titanium dioxide, titanium coupling agent treatment by isopropyl triisostearoyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate etc., metal soap treatment, acyl glutamic acid treatment Amino treatment with acid, lecithin treatment with hydrogenated egg yolk lecithin, collagen treatment, polyethylene process, moisture retention treatment, an inorganic compound treatment, and processing methods such as mechanochemical treatment.

  Specific examples of the clay minerals include components having several functions such as an extender and an adsorbent, such as talc, mica, sericite, titanium sericite (cericite coated with titanium oxide), white cloud Mothers include VEEGUM (registered trademark) manufactured by Vanderbilt.

  Specific examples of the above-mentioned perfume include anisaldehyde, benzyl acetate, geraniol and the like. Specific examples of the antiseptic and bactericidal agent include methyl paraben, ethyl paraben, propyl paraben, benzalkonium, benzethonium and the like. Specific examples of the antioxidant include dibutylhydroxytoluene, butylhydroxyanisole, propyl gallate and tocopherol. Specific examples of the anti-inflammatory agent include ε-aminocaproic acid, glycyrrhizinic acid, dipotassium glycyrrhizinate, β-glycyrrhetinic acid, lysozyme chloride, guaiazulene, hydrocortisone and the like. These can be used individually or in mixture of 2 or more types. Specific examples of the ultraviolet absorber include inorganic titanium oxide, zinc oxide particulate, cerium oxide particulate, iron oxide particulate, iron oxide particulate such as zirconium oxide particles, benzoic acid type, para aminobenzoic acid type, anthranilic acid type And organic absorbents such as salicylic acid type, cinnamic acid type, benzophenone type and dibenzoylmethane type.

  Specific examples of the special compound additives include hormones such as estradiol, estrone, ethynyl estradiol, cortisone, hydrocortisone, prednisone, vitamins such as vitamin A, vitamin B, vitamin C, vitamin E, citric acid, tartaric acid, lactic acid Skin astringent such as aluminum chloride, potassium aluminum sulfate, allantoin chlorohydroxyaluminum, zinc paraphenol sulfonate, zinc sulfate, etc., cantaris tinea, chili pepper tincture, apricot tincture, semen extract, garlic extract, hinokitiol, carpronium chloride And pentadecanoic acid glyceride, vitamin E, estrogen, a hair growth promoter such as photosensitizer, and a skin lightening agent such as phosphoric acid-L-ascorbic acid magnesium, kojic acid and the like.

  The external preparation has good slipperiness because it contains the composite particles of the present invention excellent in particle flowability. When the external preparation contains an aqueous solvent, good dispersibility of the composite particles can be obtained by the hydrophilicity of the hydrophilic metal oxide particles attached to the surface of the polymer particles.

  Hereinafter, the present invention will be specifically described by way of examples and comparative examples, but the present invention is not limited by these examples. First, each measuring method in an Example and a comparative example and a detection method of water-soluble cellulose are explained.

[Method of measuring average primary particle size of hydrophilic metal oxide particles]
The average primary particle size of the hydrophilic metal oxide particles (specifically, the Z average particle size calculated by the cumulant analysis method) is, for example, a particle size measuring apparatus by dynamic light scattering method (“Zetasizer Nano ZS manufactured by Malvern Co., Ltd.) Measure by ").

  As a measurement sample, a dispersion obtained by dispersing hydrophilic metal oxide particles to be measured in ion exchange water is used. When the assumed average primary particle diameter of the hydrophilic metal oxide particles is less than 100 nm, the dispersion is prepared so that the concentration of the hydrophilic metal oxide particles is 1% by weight, and the hydrophilic metal oxide particles are prepared. When the assumed average primary particle diameter of the particles is 100 nm or more, the dispersion is prepared such that the concentration of the hydrophilic metal oxide particles is 0.1% by weight. A cell made of polyethylene is set in the measurement section of a particle size measurement apparatus ("Zetasizer Nano ZS" manufactured by Malvern, Inc.) by the above-mentioned dynamic light scattering method, and the above dispersion is dispensed in the cell made of polyethylene to make it hydrophilic. The Z average particle size of the metal oxide particles is measured.

  The Z-average particle size is a value obtained by analyzing measurement data of a particle dispersion or the like by the dynamic light scattering method using a cumulant analysis method.

  In the cumulant analysis method, the average value of the particle size and the polydispersity index (PDI) are obtained, and the average value of the particle size is defined as the Z-average particle size. Strictly speaking, the work of fitting a polynomial to the logarithm of the G1 correlation function obtained by measurement is called a cumulant analysis, and the constant b in the following equation is called a second-order cumulant or Z-average diffusion coefficient.

LN (G1) = A + bt + ct ² + dt ³ + et ⁴ + ...
The value obtained by converting the constant b into the particle diameter using the viscosity of the dispersion and some equipment constants is the Z average particle diameter.

[Method of measuring volume average particle size of seed particles used for producing composite particles or polymer particles]
Measurement of volume average particle diameter of seed particles used for producing composite particles or polymer particles is carried out by a laser diffraction / scattering type particle size distribution measuring apparatus ("LS 13 320" manufactured by Beckman Coulter, Inc.) and a universal liquid sample module Do.

  Specifically, 0.1 g of a seed particle dispersion is added to a touch mixer (manufactured by Yamato Scientific Co., Ltd., "TOUCHMIXER MT-31") in 10 ml of a 0.1 wt% nonionic surfactant aqueous solution, and an ultrasonic cleaner (stock) It disperse | distributes using the company velvocrea company, "ULTRASONIC CLEANER VS-150", and uses what was made into the dispersion.

  The measurement is performed in a state in which the seed particles are dispersed by performing pump circulation in a universal liquid sample module, and in a state in which the ultrasonic unit (ULM ULTRASONIC MODULE) is activated. Calculate the arithmetic mean diameter in the volume-based particle size distribution. The measurement conditions are shown below.

Medium = water refractive index = 1.333
Solid's refractive index = refractive index of seed particle (1.495 if seed particle is polymethyl methacrylate particle)
PIDS relative concentration: about 40 to 55%

[Method of measuring variation coefficient of volume average particle diameter and particle diameter of composite particles or polymer particles]
The volume average particle size of the composite particles or the polymer particles is measured by Coulter Multisizer III (a measuring device manufactured by Beckman Coulter, Inc.). The measurement shall be performed using an aperture calibrated according to the MultisizerTM 3 User's Manual issued by Beckman Coulter, Inc.

  In addition, the aperture used for a measurement is suitably selected according to the magnitude | size of particle | grains (composite particle or polymer particle) of measurement object. When an aperture having a size of 50 μm was selected, Current (aperture current) was set to −800, and Gain (gain) was set to 4.

  As a sample for measurement, a touch mixer (manufactured by Yamato Scientific Co., Ltd., “TOUCHMIXER MT-31, in 0.1 ml of a 0.1 wt% nonionic surfactant aqueous solution” is used as 0.1 g of particles (composite particles or polymer particles) to be measured. ) And ultrasonic cleaner (manufactured by Vervochre Co., Ltd., “ULTRONIC CLEANER VS-150”) to be used as a dispersion. During the measurement, the inside of the beaker is gently stirred to such an extent that air bubbles do not enter, and the measurement is ended when 100,000 particles are measured. The volume average particle size of the particles is an arithmetic mean in a volume based particle size distribution of 100,000 particles.

The coefficient of variation (CV value) of the particle diameter of the composite particles or polymer particles is calculated by the following equation.
Coefficient of variation of particle size of composite particles or polymer particles = (standard deviation of particle size distribution based on volume of composite particles or polymer particles
Volume average particle diameter of composite particles or polymer particles) × 100

[Method of measuring specific surface area (measured value)]
The specific surface area of the particles (composite particles or polymer particles) was measured by the BET method (nitrogen adsorption method) described in ISO 9277 1st edition JIS Z 8830: 2001. The BET nitrogen adsorption isotherm of particles (composite particles or polymer particles) to be measured is measured using an automatic specific surface area / pore distribution measuring device Tristar 3000 manufactured by Shimadzu Corporation, and the nitrogen adsorption amount is used to determine the BET multipoint value. The specific surface area was calculated using the method. After the pretreatment by heating gas purge was performed, measurement was performed using a fixed volume method under the conditions of an adsorbent cross section of 0.162 nm ² using nitrogen as an adsorbent. In addition, specifically, the nitrogen purge is performed for 20 minutes while heating the container containing the particles at 65 ° C. for 20 minutes, and after the container is allowed to cool at room temperature, specifically, the container is heated at 65 ° C. It carried out by carrying out vacuum degassing until the pressure in a container became 0.05 mmHg or less.

[(Calculation value of specific surface area) / (Calculation value of specific surface area)]
Assuming that the volume average particle diameter of the particles (composite particles or polymer particles) is D (μm), the density of the particles is ρ (g / cm ³ ), the shape of the particles is a true sphere, and all the particles are Assuming that the particle diameter is equal to the volume average particle diameter D, the calculated value (m ² / g) of the specific surface area of the particles is given by the following equation (calculated value of the specific surface area) = 6 / ( ρ × D)
Calculated by

Therefore, the ratio of the calculated value (m ² / g) of the specific surface area to the actual value (m ² / g) of the specific surface area of the particles obtained by actual measurement (actual value of the specific surface area) / (ratio Calculated surface area)
Is the following equation (measured value of specific surface area) / (calculated value of specific surface area)
= (Measured value of specific surface area) × × × D / 6
Calculated by

[Determination method of density]
Measurement of the density of the particles (composite particles or polymer particles) is carried out according to JIS K 5101-11-1: 2004, “Method for testing pigment-Part 11: Density-Section 1: Pycnometer method” The following apparatus and reference liquid (replacement liquid with known density) were used according to the following equation, and the density of the particles (sample) was calculated according to the following formula.
Equipment: Pycnometer with 50 ml volume Reference solution: 99.5% ethanol
(Density d ¹⁵ = 0.795 g / cm ³ at 15 ° C.)
(a formula)
ρ = m _s × ρ _w (m _a −m _b + m _s )
ρ: density of sample (g / cm ³ )
m _s : weight of sample (g)
_{w w} : density of reference solution at 15 ° C (g / cm ³ )
m _a: weight of the pycnometer filled with reference liquid (g)
m _b : Weight of the pycnometer filled with the sample and the reference solution (g)

[Method of measuring the content of hydrophilic metal oxide particles]
With respect to composite particles or polymer particles obtained in Examples and Comparative Examples described later, the above-mentioned ignition residue is almost equal to the content (% by weight) of hydrophilic metal oxide particles, and therefore the following ignition residue is The ignition residue measured by the measurement method of the amount is defined as the content (% by weight) of the hydrophilic metal oxide particles.

(How to measure the ignition residue)
After weighing 1.0 g of particles (composite particles or polymer particles) to be measured, the weighed particles are burned off at 550 ° C. for 30 minutes in an electric furnace, and the weight (g) of the remaining residue is measured. Then, the weight (g) of the measured residue is divided by the weight (1.0 g) of the particles before the measurement, and it is converted to a percentage to obtain the ignition residue (% by weight).

[Method of measuring evaluation value indicating particle fluidity]
100 g of particles (composite particles or polymer particles) to be measured were weighed and used as a measurement sample. Then, with respect to particles in the measurement sample, an avalanche energy change AE (kJ) before and after avalanche is used as an evaluation value indicating particle flowability using a powder flowability measuring apparatus ("Powder Analyzer REVOLUTION" manufactured by Mercury Scientific). / Kg) was measured under the following measurement conditions. The lower the value of this AE, the higher the particle fluidity.
<Measurement conditions>
Measure 150 Avalanches at 0.3 rpm

[Hydrophilicity test]
100 g of ion exchanged water is added to a beaker, and 0.2 g of particles (composite particles or polymer particles) to be measured is placed on the liquid surface in a state of standing still. When particles are dispersed in water in less than 1 hour, it is judged that the particles have dispersibility in water (has hydrophilicity), and if particles do not precipitate from the liquid surface even after 1 hour or more It was judged that the particles do not have dispersibility in water (no hydrophilicity).

[Method of measuring adsorption amount of water-soluble celluloses to hydrophilic metal oxide particles]
For some examples, using the dispersion medium containing the hydrophilic metal oxide particles adsorbed by the water-soluble cellulose obtained in the production process of the composite particles, using the water-soluble cellulose per 1 g of the hydrophilic metal oxide particles The adsorption amount (g) was measured by the following method.

  After diluting 0.25 g of a dispersion medium containing hydrophilic metal oxide particles to which water-soluble celluloses have been adsorbed, 1 g of ion-exchanged water is added, and then diluted with a centrifuge ("Hitachi high speed cooling centrifuge manufactured by Hitachi High-Technologies Corporation. Centrifuge for 30 minutes at 25000 G using HIMAC CR22 GII "). 1 ml of 5% aqueous phenol solution is added to 1 ml of the supernatant obtained, and after 5 ml of concentrated sulfuric acid is added, it is allowed to stand for 10 minutes and then left in an aqueous solution at 25 ° C. for 10 minutes to obtain a measurement sample . The absorbance at 485 nm of the measurement sample is measured with an ultraviolet-visible spectrophotometer ("UV-visible spectrophotometer UV-2450" manufactured by Shimadzu Corporation), and the relationship between the calibration curve (absorbance and the concentration of water-soluble celluloses) The concentration (g / l) of water-soluble celluloses in the above-mentioned supernatant liquid is determined using a curve representing

  The calibration curve is prepared by the following method. That is, three types of aqueous solutions having different concentrations are prepared by adding 0.01 g, 0.05 g, and 0.1 g of water-soluble celluloses used in preparation of the dispersion medium to 100 g of ion-exchanged water. Each prepared 0.25 g of each aqueous solution is diluted with 0.75 g of ion exchanged water, and the absorbance is measured for each of the diluted aqueous solutions. Then, a calibration curve of a linear curve is created by plotting the weight and the absorbance of the water-soluble celluloses in the aqueous solution.

And the adsorption amount (g) of water-soluble celluloses per 1 g of hydrophilic metal oxide particles is calculated | required by the following formula.
D = (W _H- C x V) ÷ Ws
D: Adsorption amount of water-soluble celluloses per gram of hydrophilic metal oxide particles (g)
C: Concentration of water-soluble celluloses in the above supernatant (g / l)
W _H : Weight of water-soluble cellulose used for producing composite particles (g)
Ws: Weight of hydrophilic metal oxide particles used for producing composite particles (g)
V: Volume (1) of the aqueous medium used to prepare the dispersion medium in the production of the composite particles

[Method for detecting water-soluble cellulose present on the surface of composite particles]
The detection of celluloses present as residues on the surface of the composite particles is carried out by the following method. That is, first, 10 g of the composite particles are precisely weighed in a beaker having an inner volume of 300 ml. Next, about 150 mL of distilled water is added to the contents of the beaker, and while stirring, several drops of methanol are dropped until the composite particles are dispersed throughout the liquid without phase separation, and the mixture is stirred for about 30 minutes. After stirring, the mixture was centrifuged at a rotational speed of 3000 rpm for 20 minutes, and the supernatant was washed with no. Filter through 5 C filter paper. The obtained filtrate is collected in a beaker, concentrated and dried to about 5 ml without being completely dried, and then filtered with “GL Chromatodisc” (manufactured by GL Science, Inc., water system 13A, pore diameter 0.45 μm), and filtrate The reaction mixture was completely dried (solvent evaporation) to obtain a dried solid (extraction with distilled water and methanol). Then, the peak derived from water-soluble cellulose is detected by infrared spectroscopy (single reflection ATR (total reflection) method) with the following apparatus and conditions about the obtained dried and solidified material.

・ Measurement device: Fourier transform infrared spectrophotometer (product name "Nicolet
(Registered trademark) iS10 ", Thermo
SCIENTIFIC) and
Single reflection type horizontal ATR (product name "Smart iTR",
Thermo SCIENTIFIC company)
ATR crystal: Diamond and ZnSe lenses, angle = 42 °
・ Measurement method: One-time ATR method ・ Measurement wave number domain: 4000 cm ^{−1 to} 650 cm ⁻¹
・ Wavenumber dependence of measurement depth: not corrected ・ Detector: Deuterated triglycine sulfate (DTGS) detector
And KBr beam splitter, resolution: 4 cm ^-1
・ Number of integrations: 16 times (same for background measurement)

[Production Example 1 of Seed Particles]
(Production of primary seed particles)
In 3000 g of pure water as an aqueous medium, 520 g of ethyl methacrylate as a vinyl monomer and 9.2 g of n-octylmercaptan as a molecular weight modifier were charged into a 5 L autoclave, and the temperature was raised to 55 ° C. Thereafter, an aqueous solution in which 2.60 g of potassium peroxodisulfate as a polymerization initiator was dissolved in 120 g of pure water was added to the contents of the autoclave and purged with nitrogen. Thereafter, polymerization was carried out at 55 ° C. for 12 hours, and primary seed particles having a volume average particle diameter of 0.75 μm could be obtained in the form of a slurry.

(Production of secondary seed particles)
In 500 g of methyl methacrylate as a vinyl-based monomer, 5.3 g of 2,2'-azobis (2,4-dimethylvaleronitrile) as a polymerization initiator was dissolved to obtain a monomer mixture.

  In a 5 L container, the obtained monomer mixture is mixed with 2000 g of ion exchanged water as an aqueous medium containing 5.3 g of sodium dioctyl sulfosuccinate as a non-reactive surfactant, and a high-speed stirrer The emulsion was obtained by treating it with (trade name “Homomixer MARK II 2.5 type”, Primix Co., Ltd.) for 10 minutes at a number of revolutions of 8000 rpm. 32 g of the slurry of the primary seed particles was added to the emulsion, and the mixture was stirred for 6 hours. It was confirmed by an optical microscope that the monomer mixture in the emulsion was completely absorbed by the primary seed particles.

  Thereafter, this dispersion and 1000 g of an aqueous solution in which 19 g of polyvinyl pyrrolidone (PVP K-90, manufactured by Nippon Shokubai Co., Ltd.) as a polymer dispersion stabilizer is dissolved are put into an autoclave having an inner volume of 5 L and stirred at 60 ° C. The polymerization was performed for 8 hours, and secondary seed particles having a volume average particle diameter of 3.5 μm (hereinafter, referred to as “3.5 μm secondary seed particles”) could be obtained in a slurry state.

[Production Example 2 of Seed Particles]
(Production of primary seed particles)
In an autoclave with an internal volume of 5 L, 520 g of ethyl methacrylate as a vinyl monomer and 5.6 g of n-octylmercaptan as a molecular weight modifier are added to 3000 g of pure water as an aqueous medium, at 70 ° C. The temperature rose to the end. Thereafter, an aqueous solution prepared by dissolving 2.68 g of potassium peroxodisulfate as a polymerization initiator in 125 g of pure water was added to the contents of the autoclave and purged with nitrogen. Then, polymerization was performed at 70 ° C. for 12 hours, and primary seed particles with a volume average particle diameter of 0.45 μm could be obtained in the form of a slurry.

(Production of secondary seed particles)
In an autoclave with an inner volume of 5 L, 360 g of methyl methacrylate as a vinyl monomer, 3.6 g of n-octylmercaptan as a molecular weight modifier and the above primary seed particles (volume average particle) in 3200 g of pure water as an aqueous medium 250 g of slurry having a diameter of 0.45 μm) was charged, and the temperature was raised to 70 ° C. Thereafter, an aqueous solution prepared by dissolving 1.80 g of potassium peroxodisulfate as a polymerization initiator in 125 g of pure water was added to the contents of the autoclave and purged with nitrogen. Then, polymerization was performed at 70 ° C. for 12 hours, and secondary seed particles having a volume average particle diameter of 1.0 μm (hereinafter, referred to as “1.0 μm secondary seed particles”) could be obtained in a slurry state.

[Example 1: Production example of composite particles]
In a 5 L container having a stirrer, 1000 g of ion-exchanged water as an aqueous medium and 5.0 g of sodium dioctyl sulfosuccinate as a non-reactive surfactant were charged. In the contents of this container, 900 g of methyl methacrylate (MMA) as a vinyl monomer and 100 g of ethylene glycol dimethacrylate (EGDMA), and 2,2'-azobis (2,4-dimethyl valero as a polymerization initiator) 0.6 g of nitrile) (ADVN) and 0.6 g of benzoyl peroxide (BPO) were added. The contents of the container were stirred for 10 minutes at a rotation speed of 8000 rpm with a high-speed stirrer (trade name "Homomixer MARK II 2.5", manufactured by Primix Inc.) to obtain an emulsion. To the obtained emulsion, 80 g of the slurry of 3.5 μm secondary seed particles is added, and stirred at 30 ° C. for 3 hours at 100 rpm by the stirring device to make 3.5 μm secondary seed particles a single vinyl type. The body (methyl methacrylate and ethylene glycol dimethacrylate) was absorbed.

In an autoclave having an internal volume of 5 L, 1800 g of ion-exchanged water, and Snowtex (registered trademark) O-40 (abbreviated as “ST-O-40” as hydrophilic metal oxide particles, colloidal silica manufactured by Nissan Chemical Industries, Ltd., 85 g (SiO ₂ pure weight: 34 g) with an average primary particle diameter of 25 nm, solid content of 40% by weight, and Metroose (registered trademark) 65 SH-50 (abbreviated "HPMC (65 SH-50)" as water-soluble celluloses, Shin-Etsu Chemical Co., Ltd.) 6.8 g of hydroxypropyl methylcellulose manufactured by Co., Ltd. (cloud point 65 ° C.) was added and mixed at a temperature of 60 ° C. for 24 hours. The amount of water-soluble celluloses adsorbed on hydrophilic metal oxide particles (silica particles) was measured using this dispersion medium. As a result, 5.02 mg / m ² of water-soluble celluloses were adsorbed on hydrophilic metal oxide particles. It was The obtained mixture, 16 g of the emulsion, Aqualon (registered trademark) RN 2025 (nonion type, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., pure 25% by weight as a reactive surfactant), 0.6 g of sodium nitrate was added, and polymerization was carried out at 60 ° C. for 5 hours. Thereafter, a solid is obtained by filtration, and after washing with 5 L of water, the solid content is taken out and dried with a vacuum dryer for 12 hours to obtain composite particles.

  When a cross section of the obtained composite particle was confirmed by SEM (scanning electron microscope) and TEM (transmission electron microscope), as shown in FIG. 1 and FIG. It was found that the hydrophilic metal oxide particles (the black spots in the TEM image of FIG. 2) attached to the coalesced particles (the black spots in the TEM image of FIG. 2) were included, and there were many surface convexities derived from the hydrophilic metal oxide particles. Moreover, in this composite particle, it was found that the surface of the polymer particle was coated with a layer composed of hydrophilic metal oxide particles. The convex portion on the surface is presumed to be formed by mixing hydrophilic metal oxide particles and small particles (so-called emulsified product) of a vinyl-based monomer.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.5 μm, the variation coefficient (CV value) of the particle diameter was 11.5%, and the particle size distribution was sharp. Further, the obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.16 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 3.37, The content of the hydrophilic metal oxide particles (ignition residue) was 1.40% by weight, and the AE showing particle fluidity was 30.8 kJ / kg.

  In addition, as a result of conducting a hydrophilicity test, sedimentation starts immediately, so that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity (this means that a hydrophilic metal is formed on the surface of the composite particles). (Indicating the presence of oxide particles).

Moreover, the infrared spectroscopy measurement of the extract was performed by the method described by the term of "the detection method of the water-soluble celluloses which exist on the surface of a composite particle" about the obtained composite particle. In FIG. 1, the infrared absorption spectrum of the extract of the obtained composite particle is shown by a solid line, and the infrared absorption spectrum of hydroxypropyl methylcellulose is shown by a broken line. From the measurement results shown in FIG. 1, in the infrared absorption spectrum of the extract of the composite particle, an absorption peak attributable to the C—O—C bond is observed near wavenumber 1110 to 1000 cm ⁻¹ , CH ₃ bending vibration and − An absorption peak attributable to O-H bending vibration was observed at a wave number of 1500 to 1250 cm ⁻¹ . Since this is an infrared absorption spectrum similar to hydroxypropyl cellulose, it could be inferred that hydroxypropyl methylcellulose is present in the extract of the composite particles.

Example 2 Production Example of Composite Particle
Composite particles were obtained in the same manner as in Example 1 except that 70 g of 1.0 μm secondary seed particles were used instead of 80 g of the slurry of 3.5 μm secondary seed particles.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 4.5 μm, the variation coefficient (CV value) of the particle diameter was 12.0%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 2.58 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 2.32. The content of the hydrophilic metal oxide particles (ignition residue) was 3.20% by weight, and the AE showing particle fluidity was 42.0 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

Example 3 Production Example of Composite Particles
The same procedure as in Example 1 was repeated, except that 4 g of Adekaria Soap (registered trademark) ER-10 (nonion type, manufactured by ADEKA Corporation) was used instead of 16 g of Aqualon (registered trademark) RN 2025 as a reactive surfactant. The composite particles were obtained.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.5 μm, the variation coefficient (CV value) of the particle diameter was 11.4%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.15 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 3.34 The content of the hydrophilic metal oxide particles (ignition residue) was 1.40% by weight, and the AE showing particle fluidity was 30.6 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

Example 4 Production Example of Composite Particles
As hydrophilic metal oxide particles, instead of Snowtex (registered trademark) O-40 85 g (SiO ₂ pure weight 34 g), Snowtex (registered trademark) O (abbreviated as "ST-O", manufactured by Nissan Chemical Industries, Ltd.) Composite particles were obtained in the same manner as Example 1, except that colloidal silica, average primary particle diameter 13 nm, solid content 20% by weight, and 85 g (SiO ₂ pure weight 17 g) were used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.3 μm, the variation coefficient (CV value) of the particle diameter was 11.7%, and the particle size distribution was sharp. Further, the obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.65 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 4.72. The content of the hydrophilic metal oxide particles (ignition residue) was 1.40% by weight, and the AE showing particle fluidity was 30.5 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

Example 5 Production Example of Composite Particles
As water-soluble cellulose, in place of 6.8 g of Metrose (registered trademark) 65SH-50, Metrose (registered trademark) 65 SH-400 (abbreviated "HPMC (65SH-400)", hydroxypropyl methylcellulose manufactured by Shin-Etsu Chemical Co., Ltd.) Composite particles were obtained in the same manner as in Example 1 except that 6.8 g of a cloud point of 65 ° C. was used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.4 μm, the variation coefficient (CV value) of the particle diameter was 11.5%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.17 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 3.37, The content of hydrophilic metal oxide particles (ignition residue) was 1.40% by weight, and the AE exhibiting particle fluidity was 30.2 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

Example 6 Production Example of Composite Particles
As a water-soluble cellulose, in place of 6.8 g of Metrose (registered trademark) 65SH-50, 6.8 g of NISSO HPC M (manufactured by Nippon Soda Co., Ltd., hydroxypropyl cellulose, 45 ° C. lower limit critical solution temperature) was used. In the same manner as in Example 1, composite particles were obtained.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.5 μm, the variation coefficient (CV value) of the particle diameter was 11.6%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.16 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 3.36, The content of the hydrophilic metal oxide particles (ignition residue) was 1.40% by weight, and the AE showing particle fluidity was 30.5 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

Example 7 Production Example of Composite Particles
As a vinyl monomer, 800 g of methyl methacrylate (MMA), 100 g of styrene, and 100 g of ethylene glycol dimethacrylate (EGDMA) were used instead of 900 g of methyl methacrylate (MMA) and 100 g of ethylene glycol dimethacrylate (EGDMA). Composite particles were obtained in the same manner as in Example 2 except for the above.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 4.2 μm, the variation coefficient (CV value) of the particle diameter was 12.1%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 2.62 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 2.20. The content of the hydrophilic metal oxide particles (ignition residue) was 3.20% by weight, and the AE showing particle fluidity was 43.5 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

Example 8 Production Example of Composite Particles
As a vinyl monomer, 350 g of butyl acrylate (BA), 350 g of butyl methacrylate (BMA), and ethylene glycol dimethacrylate (EGDMA) instead of 900 g of methyl methacrylate (MMA) and 100 g of ethylene glycol dimethacrylate (EGDMA) 2.) using 300 g) and replacing it with 0.6 g of 2,2'-azobis (2,4-dimethylvaleronitrile) (ADVN) and 0.6 g of benzoyl peroxide (BPO) as a polymerization initiator; Composite particles were obtained in the same manner as in Example 2 except that 6.0 g of azobis (2,4-dimethylvaleronitrile) (ADVN) and 6.0 g of benzoyl peroxide (BPO) were used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 4.5 μm, the variation coefficient (CV value) of the particle diameter was 11.1%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 2.60 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 2.34, The content of the hydrophilic metal oxide particles (ignition residue) was 3.10% by weight, and the AE exhibiting particle fluidity was 42.1 kJ / kg.

Example 9 Production Example of Composite Particles
An aqueous dispersion GT-10W of ultrafine particle silica-coated titanium oxide particles (manufactured by Sakai Chemical Industry Co., Ltd.) as hydrophilic metal oxide particles, instead of Snowtex (registered trademark) O-40 85 g (SiO ₂ pure weight 34 g) Average primary particle diameter: 115 nm, solid content 40% by weight, silica coating amount (silica content in silica-coated metal oxide particles 20% by weight) 85 g (pure fraction of silica-coated titanium oxide particles 34 g), using In place of 0.6 g of 2,2'-azobis (2,4-dimethylvaleronitrile) (ADVN) and 0.6 g of benzoyl peroxide (BPO) as an initiator, Composite particles were obtained in the same manner as in Example 1 except that 6.0 g of valeronitrile) (ADVN) and 6.0 g of benzoyl peroxide (BPO) were used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.0 μm, the variation coefficient (CV value) of the particle diameter was 11.7%, and the particle size distribution was sharp. Further, the obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 8.61 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 24.11 The content of the hydrophilic metal oxide particles (ignition residue) was 2.45% by weight, and the AE showing particle fluidity was 40.6 kJ / kg.

Example 10 Production Example of Composite Particles
Composite particles were obtained in the same manner as in Example 9 except that 70 g of 1.0 μm secondary seed particles were used instead of 80 g of the slurry of 3.5 μm secondary seed particles.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 4.7 μm, the variation coefficient (CV value) of the particle diameter was 12.1%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 9.57 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 9.00, The content of the hydrophilic metal oxide particles (ignition residue) was 2.10% by weight, and the AE exhibiting particle fluidity was 48.5 kJ / kg.

Example 11 Production Example of Composite Particles
Ultrafine particle silica-coated zinc oxide particles FINEX-30W (Fuji Chemical Industry Co., Ltd.) as a hydrophilic metal oxide particle instead of 85 g of the ultrafine particle silica-coated titanium oxide water dispersion GT-10W (34 g of pure amount of silica-coated titanium oxide particle) Composite particles were obtained in the same manner as in Example 9 except that 34 g of an average primary particle diameter of 137 nm and a coated amount of silica (content by weight of silica in silica-coated metal oxide particles) of 34 g were used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 14.1 μm, the variation coefficient (CV value) of the particle diameter was 13.8%, and the particle size distribution was sharp. Further, the obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 6.63 m ² / g, (an actual value of the specific surface area) / a calculated value of the specific surface area of 18.70, The content of hydrophilic metal oxide particles (ignition residue) was 2.35% by weight, and the AE exhibiting particle fluidity was 38.4 kJ / kg.

Example 12 Production Example of Composite Particles
Ultrafine particle silica-coated titanium oxide water dispersion GT-10W 85 g (34 g of the net weight of the silica-coated titanium oxide particles) as hydrophilic metal oxide particles, an aqueous dispersion of antimony-doped zinc oxide particles “Cell Composite particles were obtained in the same manner as in Example 9 except that 170 g of Nux (registered trademark) CX-Z330H (manufactured by Nissan Chemical Industries, Ltd., average primary particle diameter: 20 nm, solid content 20% by weight) was used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 15.2 μm, the variation coefficient (CV value) of the particle diameter was 11.8%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of specific surface area of 3.03 m ² / g, (an actual value of specific surface area) / (a calculated value of specific surface area) of 9.21, The content of the hydrophilic metal oxide particles (ignition residue) was 2.10% by weight, and the AE exhibiting particle fluidity was 38.0 kJ / kg.

Example 13 Production Example of Composite Particles
Ultrafine particle silica-coated titanium oxide water dispersion GT-10W 85 g (34 g of pure amount of silica-coated titanium oxide particles) as hydrophilic metal oxide particles instead of the aqueous dispersion of phosphorus-doped tin oxide particles “Cenax (registered Composite particles were obtained in the same manner as in Example 9 except that 113 g of "CX-S301H" (trade name, manufactured by Nissan Chemical Industries, Ltd., average primary particle diameter: 20 nm, solid content: 30% by weight) was used.

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 15.2 μm, the variation coefficient (CV value) of the particle diameter was 12.1%, and the particle size distribution was sharp. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 3.11 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 9.45, The content of the hydrophilic metal oxide particles (ignition residue) was 2.12% by weight, and the AE showing particle fluidity was 37.6 kJ / kg.

Comparative Example 1: Comparative Production Example of Composite Particles
Do not use Snowtex (registered trademark) O-40 as hydrophilic metal oxide particles and Metrose (registered trademark) 65SH-400 as water-soluble celluloses, and Aqualon (as a reactive surfactant) Polymer particles were obtained in the same manner as in Example 1 except that 50 g of polyvinyl alcohol as a polymer dispersion stabilizer was used in place of 16 g of RN 2025 (registered trademark).

  When the cross section of the obtained polymer particle was confirmed by SEM (scanning electron microscope), as shown in FIG. 3, it was recognized that there was almost no surface unevenness.

When the particle size distribution of the obtained polymer particles was measured, the volume average particle diameter was 14.5 μm and the variation coefficient (CV value) of the particle diameter was 10.0%. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 0.40 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 1.16, AE showing particle fluidity was 84.6 kJ / kg.

  Further, as a result of conducting a hydrophilicity test, it was confirmed that there was no sedimentation even after 1 hour or more, and that the obtained polymer particles did not have dispersibility in water, that is, did not have hydrophilicity.

Comparative Example 2: Comparative Production Example of Composite Particles
Do not use Snowtex (registered trademark) O-40 as hydrophilic metal oxide particles and Metrose (registered trademark) 65SH-400 as water-soluble celluloses, and Aqualon (as a reactive surfactant) Polymer particles were obtained in the same manner as in Example 2, except that 50 g of polyvinyl alcohol as a polymer dispersion stabilizer was used in place of 16 g of RN 2025 (registered trademark).

When the particle size distribution of the obtained polymer particles was measured, the volume average particle diameter was 4.2 μm and the variation coefficient (CV value) of the particle diameter was 11.0%. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.00 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 0.84 The AE exhibiting particle fluidity was 69.1 kJ / kg.

  Further, as a result of conducting a hydrophilicity test, it was confirmed that there was no sedimentation even after 1 hour or more, and that the obtained polymer particles did not have dispersibility in water, that is, did not have hydrophilicity.

Comparative Example 3: Comparative Production Example of Composite Particles
The use amount of Snowtex (registered trademark) O-40 as the hydrophilic metal oxide particles was changed from 85 g (34 g of SiO ₂ net weight) to 480 g (192 g of SiO ₂ net weight), and as water-soluble celluloses The particles were obtained in the same manner as in Example 2 except that the Metroose (registered trademark) 65SH-400 and the aquarone (registered trademark) RN2025 as a reactive surfactant were not used.

When the particle size distribution of the obtained particles was measured, the volume average particle diameter was 4.5 μm and the variation coefficient (CV value) of the particle diameter was 11.0%. The obtained particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 1.02 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 0.92, and a hydrophilicity. The content of pyrolytic metal oxide particles (ignition residue) was less than the lower limit of determination, and the AE showing particle fluidity was 61.2 kJ / kg. The particles obtained were found to contain almost no hydrophilic metal oxide particles because the ignition residue was below the lower limit of quantification, and it was recognized that they were not composite particles but polymer particles.

  Further, as a result of conducting a hydrophilicity test, it was confirmed that there was no sedimentation even after 1 hour or more, and that the obtained polymer particles did not have dispersibility in water, that is, did not have hydrophilicity.

Comparative Example 4: Comparative Production Example of Composite Particles
Due to changes in their Snowtex amount of (R) O-40 as the hydrophilic metal oxide particles from 85 g (SiO ₂ Jun quantity 34g) in 210g (SiO ₂ Jun quantity 84 g), Metolose as a water-soluble cellulose Example 1 except using sodium chloride 72 g which is an alkali metal salt instead of 6.8 g (registered trademark) 65SH-400 and not using Aqualon (registered trademark) RN2025 as a reactive surfactant Seed polymerization was tried in the same manner as in. However, the droplet stability of the monomer mixture in the dispersion medium was low, and composite particles could not be obtained.

Comparative Example 5 Comparative Production Example of Composite Particles
150 g of water as an aqueous medium, Snowtex (registered trademark) O-40 (abbreviated as "ST-O-40", abbreviated as "ST-O-40", colloidal made by Nissan Chemical Industries, Ltd.) in a polymerization vessel having a stirring device Silica, average primary particle diameter 25 nm, solid content 40% by weight 2.75 g (SiO ₂ pure weight 1.1 g), and Metroose (registered trademark) 65SH-400 (abbreviated as HPMC (65SH-400) as water-soluble celluloses ), 0.22 g of hydroxypropyl methylcellulose manufactured by Shin-Etsu Chemical Co., Ltd., and a cloud point of 65 ° C. were added and mixed for 24 hours at a temperature of 60 ° C. Thereby, a hydrophilic metal oxide to which water-soluble celluloses were adsorbed. A dispersion medium containing particles (silica particles) was obtained.

  Separately, 50 g of methyl methacrylate (MMA) as a vinyl monomer and 2.5 g of ethylene glycol dimethacrylate (EGDMA), and 2,2′-azobis (2,4-dimethylvaleronitrile) (a polymerization initiator) 0.5 g of ADVN) was uniformly mixed and dissolved to prepare a monomer mixture containing a polymerization initiator.

  A monomer mixture containing this polymerization initiator is added to the above-mentioned dispersion medium in the above-mentioned polymerization vessel, and it is stirred for about 3 minutes at 9000 rpm with a homomixer (high flex disperser HG-2 manufactured by SMT), and the above-mentioned dispersion medium The above monomer mixture was finely dispersed therein.

  Thereafter, the stirring was continued at a stirring speed of 70 rpm, and polymerization was performed for 6 hours after the temperature of the dispersion medium to which the monomer mixture was added reached 55 ° C.

  Then, while stirring, the reaction liquid in the polymerization vessel was cooled to room temperature. Then, the reaction solution is suction filtered using qualitative filter paper 101 ("Toyo qualitative filter paper" manufactured by Advantec Toyo Kaisha, Ltd.), washed with ion-exchanged water, and then drained, and then dried overnight in an oven at 90 ° C. The composite particles were obtained by

When the particle size distribution of the obtained composite particles was measured, the volume average particle diameter was 7.9 μm and the variation coefficient (CV value) of the particle diameter was 36.3%. The obtained composite particles have a density of 1.2 g / cm ³ , an actual value of the specific surface area of 0.63 m ² / g, (an actual value of the specific surface area) / (a calculated value of the specific surface area) of 1.00, The content of the hydrophilic metal oxide particles (ignition residue) was 1.45% by weight, and the AE showing particle fluidity was 56.8 kJ / kg.

  Moreover, as a result of conducting a hydrophilicity test, since sedimentation immediately began, it was confirmed that the obtained composite particles have dispersibility in water, that is, they have hydrophilicity.

  In Examples 1 to 13 and Comparative Examples 1 to 5, the amounts of the various raw materials used in the production, the measurement results of the average primary particle diameter of the hydrophilic metal oxide particles used in the production, the particles obtained by the production (composite Volume average particle diameter of particles or polymer particles, coefficient of variation of particle diameter (CV value), measured value of specific surface area, (measured value of specific surface area) / (calculated value of specific surface area), hydrophilic metal oxide particles Table 1 and Table 2 show measurement results of AE showing the content of (ignition residue) and particle fluidity.

  As described above, in the manufacturing methods of Comparative Examples 3 and 4 in which the water-soluble cellulose is not used, composite particles including polymer particles and hydrophilic metal oxide particles attached to the surface of the polymer particles are obtained. However, in the production methods of Examples 1 to 13 using water-soluble cellulose, composite particles containing polymer particles and hydrophilic metal oxide particles attached to the surface of the polymer particles are used. I was able to get

  In addition, the polymer particles of Comparative Examples 1 to 3 do not contain hydrophilic metal oxide particles, or do not contain hydrophilic metal oxide particles, whereas the composite particles of Examples 1 to 13 have It has been found that the polymer particles are hydrophilic because they contain hydrophilic metal oxide particles attached to the surface of the polymer particles in addition to the polymer particles.

  In addition, the polymer particles of Comparative Examples 1 to 3 and the composite particles of Comparative Example 5 have less surface unevenness, whereas (measured value of specific surface area) / (calculated value of specific surface area) is less than 1.20. The composite particles of Examples 1 to 13 were found to have many surface irregularities, and (measured value of specific surface area) / (calculated value of specific surface area) was 1.20 or more.

  In addition, the polymer particles of Comparative Examples 1 to 3 and the composite particles of Comparative Example 5 have AE showing particle fluidity of more than 50 kJ / kg, and the particle fluidity is low, while the composite of Examples 1 to 13 The particles were found to have an AE of 50 kJ / kg or less, which exhibits particle fluidity, and high particle fluidity.

  The composite particles of Comparative Example 5 have a variation coefficient of particle diameter of more than 15%, and the uniformity of the particle diameter is low, while the composite particles of Examples 1 to 13 have a variation coefficient of particle diameter of 15 %, And it was found that the uniformity of the particle size was high.

Example 14 Production Example of Optical Film
1.5 g of an aqueous binder resin (made by Daido Chemical Industries, Ltd., trade name "E-5221P", solid content 20% by weight, urethane binder) as a binder resin, and 0.5 g of the composite particles prepared in Example 1 The mixture was mixed, and the composite particles were uniformly dispersed in the aqueous binder resin to prepare a coating agent (resin composition for coating).

  This coating agent was applied onto a 100 μm thick PET film as a base film using a 100 μm applicator (width 8 cm) to form a wet coated film. The coated film on the PET film is dried by heating in a constant temperature bath at 70 ° C. for 10 minutes, and a substrate film and a coating of 8 cm long (applicator width) × 30 cm wide (dry state) formed thereon And a coated film of

  When the aqueous binder resin and the composite particles were mixed, the composite particles were immediately dispersed uniformly in the aqueous binder resin. Moreover, when the fault which generate | occur | produced in the coating (coating film of a dry state) formed on the base film was confirmed visually, there was no fault which generate | occur | produced but the composite particle was in the state disperse | distributed uniformly.

Comparative Example 6: Comparative Production Example of Optical Film
A film was obtained in the same manner as in Example 8 except that the polymer particles produced in Comparative Example 1 were used instead of the composite particles produced in Example 1. When the aqueous binder resin and the composite particles were mixed, it was easy to catch. Moreover, when the fault which generate | occur | produced in the coating (coating film of a dry state) formed on the base film was visually confirmed, there were ten or more faults which generate | occur | produced.

Example 15 Production Example of Light Diffusing Plate
5.0 parts by weight of the composite particles obtained in Example 10, and methacrylic resin (trade name "ACRIPET (registered trademark) MF 001 G200", manufactured by Mitsubishi Rayon Co., Ltd.) 100 which is a transparent resin as a base resin After overnight drying in an oven set at 80 ° C. with parts by weight, the mixture was melt-kneaded at 200 ° C. in an extruder and then pelletized to obtain pellets as a resin composition. The obtained pellet was molded by an injection molding machine under conditions of a cylinder temperature of 230 ° C. to produce a light diffusion plate as a molded body of 2 mm thickness and 50 mm × 100 mm.

[Measurement of total light transmittance and haze of light diffuser]
The haze and the total light transmittance of the light diffusing plate obtained in Example 15 were measured using a haze meter “NDH-4000” manufactured by Nippon Denshoku Kogyo Co., Ltd. The measurement of the total light transmittance was carried out according to JIS K 7361-1 and the measurement of the haze according to JIS K 7136 respectively. The measurement results of total light transmittance and haze of the obtained light diffusion plate are shown in Table 3.

  The haze and the total light transmittance shown in Table 3 are average values of the measured values of three measurement samples (number of measurement samples n = 3). The value of the haze is higher as the diffusivity of the light (transmitted light) transmitted through the light diffusing plate is higher.

[Example 16: Production example of external preparation (lotion)]
0.5 parts by weight of the composite particles obtained in Example 9 was mixed with 65.0 parts by weight of ethanol, 33.0 parts by weight of purified water, and 0.1 parts by weight of a fragrance to prepare a lotion as an external preparation. . The produced lotion had extremely good redispersibility of the composite particles, and the feeling in use was also excellent.

  The composite particle of the present invention is, for example, an additive (glossy) of a coating agent (composition for coating) used as a coating agent for paper, a coating agent for paper, a coating agent for information recording paper, or a coating agent for optical members such as optical films. Erasers, coating film softeners, designability-imparting agents, etc .; light diffusing agents incorporated in light diffusing resin compositions for producing light diffusers (lighting covers, light diffusing plates, light diffusing films, etc.) Anti-blocking agents for films such as food packaging films; Additives for external preparations such as cosmetics (additives for improving slipperiness or correcting defects in the skin such as stains and wrinkles) It can be used as a raw material for

  The present invention can be practiced in other various forms without departing from the spirit or main features thereof. Therefore, the above embodiments are merely illustrative in every point and should not be interpreted in a limited manner. The scope of the present invention is indicated by the claims, and is not limited at all by the text of the specification. Furthermore, all variations and modifications that fall within the equivalent scope of the claims fall within the scope of the present invention.

Moreover, this application claims priority based on Japanese Patent Application No. 2015-171019 filed in Japan on August 31, 2015. By reference to this, the entire content of which is incorporated into the present application.

Claims (15)

A composite particle comprising a polymer particle comprising a copolymer of a vinyl monomer and a reactive surfactant, and a hydrophilic metal oxide particle attached to the surface of the polymer particle,
It further contains water-soluble celluloses,
Assuming that the shape of the composite particle is a true sphere, the following equation (calculated value of specific surface area) = 6 / (ρ ×) from volume average particle diameter D (μm) and density ρ (g / cm ³ ) of the composite particle D)
Ratio between the calculated value of the specific surface area calculated by (m ² / g) and the measured value of the specific surface area (m ² / g) of the composite particles obtained by the actual measurement (measured value of the specific surface area) / (Calculated value of specific surface area)
Are 1.20 or more. A composite particle according to claim 1 , wherein
Composite particle characterized in that the coefficient of variation of particle diameter is 15% or less. A composite particle according to claim 1 or 2 , wherein
Composite particles having a volume average particle size of 1 to 20 μm. A composite particle according to any one of claims 1 to 3 , which is
Content of the said hydrophilic metal oxide particle is in the range of 0.5 to 10 weight%, The composite particle characterized by the above-mentioned. It is a composite particle according to any one of claims 1 to 4 ,
Composite particles characterized in that the average primary particle diameter of the hydrophilic metal oxide particles is in the range of 5 to 200 nm. The composite particle according to any one of claims 1 to 5 , wherein
Composite particle characterized in that the numerical value of avalanche energy change AE before and after avalanche, which shows particle fluidity, is in the range of 10 to 50 kJ / kg. A method for producing composite particles comprising polymer particles comprising a polymer of a vinyl-based monomer, and hydrophilic metal oxide particles attached to the polymer particles,
After the vinyl-type monomer is absorbed by the seed particles, the vinyl-type monomer in an aqueous medium is present in the presence of the hydrophilic metal oxide particles in which the water-soluble cellulose is adsorbed on the surface and the reactive surfactant. A method for producing composite particles, comprising a polymerization step of obtaining composite particles by seed polymerization to be polymerized. It is a manufacturing method of composite particles according to claim 7 .
A method of producing composite particles, wherein hydroxypropyl cellulose and / or hydroxymethyl propyl cellulose is used as the water-soluble cellulose. A method of producing composite particles according to claim 7 or 8 , wherein
Before the polymerization step, the method includes an adsorption step of treating the hydrophilic metal oxide particles with the water-soluble cellulose to cause the water-soluble cellulose to be adsorbed on the surface of the hydrophilic metal oxide particles. Method for producing composite particles. The method for producing composite particles according to any one of claims 7 to 9 , wherein
A method of producing composite particles, wherein a nonionic reactive surfactant is used as the reactive surfactant. A coating agent comprising the composite particle according to any one of claims 1 to 6 . An optical film comprising a substrate film and a coating formed thereon,
An optical film comprising the composite particle according to any one of claims 1 to 6 , wherein the coating. A resin composition comprising the polymer particles according to any one of claims 1 to 6 and a base resin. A molded article comprising the resin composition according to claim 13 . An external preparation comprising the polymer particles according to any one of claims 1 to 6 .