TWI534159B - Resin particle and use thereof - Google Patents

Description

Resin particles and their uses

The present invention relates to a resin particle having excellent dispersibility for a solvent and a binder, and is mainly applicable to a matting agent for a coating material, a light diffusing agent (a light diffusing agent for an antiglare film, a light diffusing agent for an optical diffusion film, etc.), and the like Uses (coating composition, optical film, external preparation, and light diffusing resin composition).

Conventionally, crosslinked resin particles such as propylene-based crosslinked resin particles and styrene-based crosslinked resin particles are generally used as a matting agent for paints, an optical diffusing film constituting a lighting cover, a liquid crystal display device, an antiglare film, a light diffusing plate, and the like. A light diffusing agent of the light diffusing member. In order to provide the resin particles with functions such as a matting function, an anti-glare function, and a light-diffusing function, when the resin particles are used as a matting agent for a coating, a light diffusing agent for an optical diffusion film, or a light diffusing agent for an anti-glare film, The coating material obtained by dispersing the resin particles in the binder solution is coated on the substrate, causing irregularities on the surface of the coating layer by the resin particles.

When resin particles are used as these coating materials, it is required to be able to well ensure the pot life of the coating material and to maintain the surface state of the coating material after the coating. Therefore, the solvent and binder resin as a raw material of the coating material must have good affinity with the resin particles.

In order to solve the above problems, Patent Document 1 discloses a resin particle in which at least a hydroxyl group and/or a carboxyl group are present on the surface.

Further, although the above problem is not solved, Patent Document 2 discloses a functional propylene-based polymer shaped particle in which a functional group such as a carboxyl group, a hydroxyl group or an amino group is limited to the surface of the particle.

Further, Patent Document 3 discloses a beaded crosslinked polymer obtained by suspension polymerization of a mixture containing a non-crosslinkable monomer mixture and a crosslinkable monomer, the non-crosslinkable monomer mixture containing an alkane a hydroxyalkyl (meth) acrylate having 1 to 8 carbon atoms and an alkyl methacrylate having 1 to 13 carbon atoms in the alkyl group, the crosslinkable monomer having 2 in the molecule The above double keys.

Prior art literature Patent literature

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2002-249525

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2005-29766

[Patent Document 3] Japanese Patent Laid-Open No. Hei 7-105052

The resin particles of the prior art disclosed in the above Patent Documents 1 to 3 are all obtained by copolymerizing a monomer having a hydrophilic functional group, and thus have a hydrophilic portion. However, since the hydrophilic portion has only one functional group such as a hydroxyl group, a carboxyl group or an amino group at the terminal end, and the chain length is short, the thickness of the hydrophilic region on the surface of the particle is insufficient, and sufficient hydrophilicity cannot be imparted to the resin particle. Further, since the hydrophilic portion of the resin particles of the prior art has a short chain length, when the resin particles are mixed with other components such as a binder solution to form a composition, the resin particles cannot be sufficiently improved, for example, for substances contained in other components. Affinity, such as a binder having a hydrophilic functional group such as a hydroxyl group, an aqueous solvent, or the like. As a result, the dispersion stability of the resin particles of the prior art is not sufficient for the other components such as the binder solution.

An object of the present invention is to provide a resin particle excellent in hydrophilicity and excellent in dispersion stability when mixed with other components such as a binder solution, and a coating composition, an optical film, an external preparation, and light diffusibility using the resin particle. Resin composition.

The present inventors have made intensive studies to solve the above problems, and finally found that by using a (meth) acrylate having a specific structure in a specific ratio in a monomer mixture, it is possible to obtain excellent hydrophilicity and dispersion stability to a binder solution or the like. Excellent resin particles and achieve the present invention.

In order to solve the above problems, a resin particle of the present invention is obtained by polymerizing a monomer mixture having an oxygen-extended ethyl chain having a chain length of 1 to 50 and a chain length of 1 in an aqueous medium. a monofunctional (meth) acrylate having at least one of an oxygen propyl chain of 50, a monofunctional vinyl monomer other than the above monofunctional (meth) acrylate, and a crosslinkable monomer, The total length of the chain length of the oxygen-extended ethyl chain and the chain length of the oxygen-extended propyl chain is 2 or more, and the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 weight. The amount of the above monofunctional (meth) acrylate is in the range of 0.1 to 20 parts by weight.

Since the resin particles of the present invention are obtained by polymerizing a monomer mixture in an aqueous medium, the monomer mixture contains 100 parts by weight of a monofunctional vinyl monomer and a crosslinkable monomer, and has 0.1 or more parts by weight of a monofunctional (meth)acrylate having at least one of an oxygen-extended ethyl chain and an oxygen-extended propyl chain having a chain length of 2 or more, so that a sufficient amount of chain length is long on the surface of the resin particle The hydrophilic portion is at least one of an oxygen-extended ethyl chain and an oxygen-extended propyl chain having a total chain length of 2 or more. Therefore, the resin particles of the present invention have a hydrophilic portion at the central portion of the molecular chain (the portion excluding the end portion), and have a hydrophilic region having a sufficiently large thickness direction (radial direction), so that the hydrophilicity is excellent. . Further, since the resin particles of the present invention have a sufficient amount of such a hydrophilic portion having a long chain length, when mixed with other components such as a binder solution, hydrophilic substances contained in other components (for example, hydrophilic groups such as hydroxyl groups) The functional group-based binder, aqueous solvent, and the like have high affinity and excellent dispersibility for the hydrophilic substance. As a result, when the resin particles having the above-described composition are mixed with other components such as a binder solution, it is possible to maintain excellent dispersion stability (for other components) not only chemically but also physically. Further, by the hydrophilic portion having a long chain length, even if the coating composition for dispersing the resin particles of the present invention in the binder solution is coated and hardened, the cured coating composition The dispersibility of the resin particles in the (coating film) can also be improved.

Further, in the resin particles of the present invention, the chain length of the oxygen-extended ethyl chain and the oxygen-extended propyl chain is 50 or less. Therefore, the polymerization stability of the monomer mixture at the time of polymerization is good, and it can be easily produced.

In the resin particles of the present invention, when the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the amount of the monofunctional (meth) acrylate is 20 parts by weight or less. Therefore, the monomer mixture has good polymerization stability at the time of polymerization, and can be easily produced.

Further, the resin particles of the present invention are obtained by polymerizing a monomer mixture containing a monofunctional monomer (monofunctional (meth) acrylate and monofunctional vinyl monomer) and a crosslinkable monomer. Therefore, it is a crosslinked resin particle and has good solvent resistance.

In addition, in the present specification, "(meth)acryl" means propylene or methacryl, and "(meth)acryl" means acrylic or methacryl.

Since the resin particles of the present invention have the above-described excellent properties, they can be applied to a light diffusing agent for an optical film such as an optical diffusing film or an antiglare film, a matting agent for a coating material, a cosmetic raw material, or the like.

A coating composition according to the present invention, which comprises the resin particles of the present invention. Since the composition for a coating composition of the present invention contains the resin particles of the present invention having excellent dispersion stability, the resin particles are highly dispersed, and thus optical properties such as light diffusibility and light permeability are excellent.

An optical film of the present invention is obtained by applying the composition for a coating of the present invention onto a substrate film. Since the optical film of the present invention is obtained by coating a coating composition of the present invention in which the resin particles are highly dispersed, the optical properties such as light diffusibility and light transmittance are excellent.

An external preparation of the present invention is characterized by comprising the resin particles of the present invention. Since the coating composition of the present invention contains the resin particles of the present invention having excellent dispersion stability, the resin particles are highly dispersed, so that the coating property is excellent, smooth and non-sticky, and redispersibility in the aqueous liquid external preparation. Also excellent.

A light diffusing resin composition of the present invention contains the resin particles of the present invention and a transparent substrate resin. Since the composition for a coating composition of the present invention contains the resin particles of the present invention having excellent dispersion stability, the resin particles are highly dispersed in the transparent base resin, and therefore optical properties such as light diffusibility and coating properties are excellent.

As described above, according to the present invention, it is possible to provide a resin particle which is excellent in hydrophilicity and excellent in dispersion stability when mixed with other components such as a binder solution, and a coating composition, an optical film, an external preparation, and the like which use the resin particle. And a light diffusing resin composition.

[resin particles]

The resin particles of the present invention are explained in more detail below.

A resin particle of the present invention obtained by polymerizing a monomer mixture containing an oxygen-extended ethyl chain having a chain length of 1 to 50 and an oxygen extension having a chain length of 1 to 50 in an aqueous medium Monofunctional (meth) acrylate having at least one of a propyl chain (hereinafter referred to as "hydrophilic monofunctional (meth) acrylate"), monofunctionality other than the above monofunctional (meth) acrylate The vinyl monomer and the crosslinkable monomer are characterized in that the chain length of the oxygen-extended ethyl chain and the chain length of the oxygen-extended propyl chain are 2 or more, and the monofunctional vinyl monomer When the total amount of the crosslinkable monomer is 100 parts by weight, the amount of the monofunctional (meth) acrylate is in the range of 0.1 to 20 parts by weight.

The above hydrophilic monofunctional (meth) acrylate is a compound having one polymerizable alkenyl group (generalized vinyl group) in one molecule, and the compound has an oxygen-extended ethyl chain having a chain length of 1 to 50. The following general formula

-(C ₂ H ₄ O) _m -

(m is a number from 1 to 50)

The molecular chain and the oxygen-extended propyl chain having a chain length of 1 to 50, that is, the following formula

-(C ₃ H ₆ O) _n -

(n is a number from 1 to 50)

At least one of the molecular chains to be represented, and the total chain length m of the oxygen-extended ethyl chain and the chain length n of the oxygen-extended propyl chain are 2 or more in total.

When the chain length n of the oxygen-extended ethyl chain or the chain length n of the oxygen-extended propyl chain exceeds 50, the polymerization stability is lowered, and it is difficult to obtain the resin particles, which is not preferable. When the total chain length m of the oxygen-extended ethyl chain and the chain length n of the oxygen-extended propyl chain are less than 2, the chain length of the hydrophilic portion is too short, and the wettability of the resin particles to the aqueous medium is deteriorated. At the same time, the dispersibility of the resin particles to the binder resin having a hydrophilic functional group such as a hydroxyl group and the solvent is deteriorated, which is not preferable. Preferably, the chain length m of the oxygen-extended ethyl chain and the chain length n of the oxygen-extended propyl chain are each in the range of 1 to 30. Therefore, the polymerization stability can be further improved, and the resin particles can be obtained more easily.

The hydrophilic monofunctional (meth) acrylate is, for example, a compound represented by the following formula (1).

(wherein R ₁ represents H or CH ₃ , m is a number from 1 to 50, n is a number from 1 to 50 (wherein the total of m and n is 2 or more), and R ₂ represents H or CH ₃ )

As the compound represented by the above formula (1), poly(ethylene glycol-propylene glycol) monomethacrylate, polypropylene glycol monomethacrylate, methoxypolyethylene glycol monomethacrylate is preferably used. Wait.

As the compound represented by the above formula (1), a commercially available product can be used. For example, the "Brenmar (registered trademark)" series manufactured by Nippon Oil Co., Ltd. can be cited as the commercially available product. In addition, in the "Brenmar (registered trademark)" series, one type of poly(ethylene glycol-propylene glycol) monomethacrylate is used, that is, "Brenmar (registered trademark) 70PEP-350B" (containing the above formula (1) a mixture of a plurality of compounds, wherein R ₁ is CH ₃ , m is about 5 on average, n is about 2 on average, R ₂ is H), and poly(ethylene glycol-propylene glycol) monomethacrylate is one of "Brenmar (registered trademark) 50PEP-300" (containing a mixture of a plurality of compounds represented by the above formula (1), R ₁ is CH ₃ , m is about 3.5 on average, n is about 2.5 on average, and R ₂ is H) One type of polyethylene glycol monomethacrylate, that is, "Brenmar (registered trademark) PE-200" (containing a mixture of a plurality of compounds represented by the above formula (1), R ₁ is CH ₃ , m is about It is 4.5, n is about 0 on average, R ₂ is H), and one type of polypropylene glycol monomethacrylate is "Brenmar (registered trademark) PP-500" (containing a plurality of compounds represented by the above formula (1) a mixture, R ₁ is CH ₃ , m is 0, n is about 9 on average, and R ₂ is H), "Brenmar (registered trademark) PP-1000" (containing a plurality of compounds represented by the above formula (1) The mixture, R ₁ is CH ₃ m is 0, n on average about 4 to about 6, R ₂ is H), methoxy polyethylene glycol monomethacrylate one kind i.e. "Brenmar (registered trademark) PME-400" (contains the formula (1) A mixture of a plurality of compounds represented by R ₁ being CH ₃ , m having an average of about 9, n being 0, and R ₂ being CH ₃ ). These hydrophilic monofunctional (meth) acrylates may be used alone or in combination of two or more.

When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the hydrophilic monofunctional (meth) acrylate is used in an amount of 0.1 to 20 parts by weight. When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the hydrophilic monofunctional (meth) acrylate is used in an amount of less than 0.1 part by weight, and it is difficult to obtain the above hydrophilicity. Effect of a monofunctional (meth) acrylate (improving the wettability of the resin particles to an aqueous medium while improving the dispersibility of the resin particles to a binder resin having a functional group such as a hydroxyl group and a solvent), and thus good. When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, when the hydrophilic monofunctional (meth) acrylate is used in an amount exceeding 20 parts by weight, the polymerization stability is lowered. Sex, it is difficult to obtain resin particles, so it is not good.

The monofunctional vinyl monomer is a compound having one polymerizable alkenyl group (generalized vinyl group) in one molecule, and is a compound different from the above monofunctional (meth) acrylate. As the monofunctional vinyl monomer, an aromatic vinyl monomer such as styrene or α-methylstyrene; methyl (meth)acrylate, ethyl (meth)acrylate or (meth)acrylic acid can be used. a (meth) acrylate monomer such as propyl ester, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate or t-butyl (meth) acrylate; halogenated ethylene Monomer; vinyl cyanide monomer. These monofunctional vinyl monomers may be used singly or in combination of two or more.

As the monofunctional vinyl monomer, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, (A) are preferably used. An alkyl (meth)acrylate having an alkyl group having 1 to 4 carbon atoms, such as n-butyl acrylate, isobutyl (meth)acrylate or t-butyl (meth)acrylate, and selected from styrene A mixture of at least one styrenic monomer in a group consisting of α-methylstyrene. Therefore, it is possible to achieve high light transmittance and to have resin particles suitable for the refractive index of the light diffusing agent (particularly, the refractive index in the range of 1.505 to 1.580).

The crosslinkable monomer is a compound having a plurality of polymerizable alkenyl groups (generalized vinyl groups) in one molecule. Examples of the crosslinkable monomer include divinylbenzene, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, and triethylene glycol tri(meth)acrylate. Trimethylolpropane tri(meth)acrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, and the like. The crosslinkable monomer used in the present invention is preferably at least selected from the group consisting of ethylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, and divinylbenzene. 1 species. Since these crosslinkable monomers have a short chain length, the amount thereof is small and the solvent resistance can be improved, and since the hydrophobicity is high, it is easy to obtain the resin particles by adding a hydrophilic monofunctional (meth) acrylate. Dispersion stabilization effect. These crosslinkable monomers may be used singly or in combination of two or more.

The amount of the crosslinkable monomer to be used is not particularly limited, and when the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the amount of the crosslinkable monomer is preferably It is in the range of 1 to 50 parts by weight. When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the amount of the crosslinkable monomer used is less than 1 part by weight, and the solvent resistance of the resin particles is lowered. Not good. When the solvent resistance of the resin particles is lowered, when mixed with other components containing a solvent such as a binder solution, the resin particles absorb the solvent, and the viscosity of the mixture (for example, a coating composition) is increased, and the usability of the mixture is lowered. In addition, when the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, and the amount of the crosslinkable monomer used exceeds 50 parts by weight, the resin particles hardly absorb the solvent. Therefore, when the crosslinkable monomer is added in an amount of more than 50 parts by weight, the production cost is not only increased, but also the effect of increasing the crosslinkable monomer (the effect of improving the solvent resistance of the resin particles) is hardly exhibited. Not good.

In the polymerization for obtaining the resin particles of the present invention, the above monomer mixture is dispersed in an aqueous medium and then polymerized. The aqueous medium is not particularly limited, and examples thereof include a mixed medium of water, water, and a water-soluble organic medium (lower alcohol such as methanol or ethanol (an alcohol having 5 or less carbon atoms). In order to stabilize the resin particles, the above When the monomer mixture is 100 parts by weight, the aqueous medium is usually used in an amount of from 100 to 1,000 parts by weight.

The polymerization temperature of the above monomer mixture is preferably in the range of from 30 to 100 °C. The time for maintaining the polymerization temperature is preferably in the range of from 0.1 to 20 hours. After the completion of the polymerization, if necessary, the resin particles are separated by centrifugation to remove the aqueous medium, and after washing with water and a solvent, drying is performed to separate the resin particles.

In the polymerization of the above monomer mixture, a polymerization initiator is usually added to the above monomer mixture. Examples of the polymerization initiator include peroxides such as benzammonium peroxide, lauric acid peroxide, and third butyl peroxyisobutyrate; 2,2'-azobisisobutyronitrile, 2,2 , azo such as azobis(2,4-dimethylvaleronitrile) and 2,2-azobis-(2-methylpropionate); peracids such as potassium persulfate or ammonium persulfate Salt and so on. These polymerization initiators may be used alone or in combination of two or more.

When the above monomer mixture is 100 parts by weight, the polymerization initiator is preferably used in an amount of from 0.01 to 10 parts by weight, more preferably from 0.01 to 5 parts by weight. When the monomer mixture is used in an amount of 100 parts by weight, if the amount of the polymerization initiator used is less than 0.01 parts by weight, it is difficult to achieve a function of initiating polymerization of the polymerization initiator. In addition, when the monomer mixture is 100 parts by weight, the polymerization initiator is used in an amount exceeding 10 parts by weight, which is uneconomical in terms of cost, and thus is not preferable.

Further, when the surfactant concentration of the reaction liquid (emulsion) is equal to or higher than the critical micelle concentration, it is preferred to use benzamidine peroxide or 2,2'-azo two as the polymerization initiator. An oil-soluble polymerization initiator such as isobutyronitrile. When the concentration of the surfactant in the reaction liquid (emulsion) is equal to or higher than the critical cell concentration, if a water-soluble polymerization initiator such as potassium persulfate is used as the polymerization initiator, new particles other than the target resin particles are formed, and thus good.

In the polymerization of the above monomer mixture, a dispersion stabilizer may be used as needed. The dispersion stabilizer is not particularly limited, and a known one can be used. Examples of the dispersion stabilizer include water-soluble polymers such as polyvinyl alcohol and polyvinylpyrrolidone; and poorly water-soluble inorganic salts such as tricalcium phosphate, calcium carbonate, and magnesium pyrophosphate. These dispersion stabilizers may be used alone or in combination of two or more.

In the polymerization of the above monomer mixture, it is preferred that the aqueous medium contains a surfactant. The surfactant is not particularly limited, and any of an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant can be used.

Examples of the anionic surfactant include fatty acid oils such as sodium oleate and castor oil; alkyl sulfates such as sodium lauryl sulfate and ammonium lauryl sulfate; and alkylbenzenesulfonic acids such as sodium dodecylbenzenesulfonate. Salt; alkylnaphthalene sulfonate; alkane sulfonate; dialkyl sulfosuccinate such as sodium dioctyl sulfonate; polyoxyethylene alkyl phenyl ether sodium phosphate, polyoxyalkylene aryl Phosphate salts such as sodium ether phosphate; naphthalenesulfonic acid formaldehyde condensate; polyoxyethylene alkyl phenyl ether sulfate; polyoxyethylene alkyl sulfate.

Examples of the nonionic surfactant include polyoxyethylene alkyl ethers such as tridecethoxyethylene ether, polyoxyethylene alkyl phenyl ethers, styrene phenol polyoxyethylene ethers, and carbon atoms of alkylene groups. a polyalkylene oxide such as a tridecyl polyoxyalkylene ether having a number of 3 or more, a polyoxyethylene fatty acid ester, a sorbitan fatty acid ester, or a polyoxyethylene sorbitan monolaurate An oxyethylene sorbitan fatty acid ester, a polyoxyethylene alkylamine, a glycerin fatty acid ester, and an oxyethylene-propylene oxide block copolymer.

The cationic surfactant may, for example, be an alkylamine salt such as laurylamine acetate or octadecylamine acetate; or a fourth-order ammonium salt such as dodecyltrimethylammonium chloride.

The zwitterionic surfactant may, for example, be a dodecyl dimethylamine oxide, a phosphate ester or a phosphite surfactant.

Among these surfactants, at least one of an anionic surfactant and a nonionic surfactant is preferably used. These surfactants may be used alone or in combination of two or more.

When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100% by weight, it is preferred that the amount of the surfactant used in the polymerization of the monomer mixture be in the range of 0.01 to 5 parts by weight. When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the amount of the surfactant used is less than 0.01 part by weight, and it is difficult to maintain polymerization stability, which is not preferable. In addition, when the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, when the amount of the surfactant used exceeds 5 parts by weight, new particles other than the target resin particles are formed and reduced. It is not preferable as a function of a light diffusing agent or the like.

In the polymerization for obtaining the resin particles of the present invention, a chain transfer agent, an antioxidant, or the like may be added to the reaction system in order to improve the heat resistance of the resin particles. Examples of the chain transfer agent include mercaptans such as n-octyl mercaptan (1-octyl mercaptan), n-dodecyl mercaptan, and tridecyl mercaptan; γ-terpinene, dipentene, and the like. Anthraquinone; halogenated hydrocarbon such as chloroform or tetrabasic carbon, α-methylstyrene dimer, and the like.

The polymerization method for obtaining the monomer mixture of the resin particles of the present invention is not particularly limited as long as it is a method of performing polymerization in an aqueous medium, and an emulsion polymerization method, a dispersion polymerization method, a seed polymerization method, or the like can be used. method. Among these polymerization methods, the seed polymerization method is preferred. The seed crystal polymerization method is preferable because it can obtain resin particles having a narrow particle size distribution which can be applied to various applications. In addition, the particle diameter of the resin particles which can be obtained by the seed polymerization method is suitable as a constituent element of a coating composition for coating a base film or the like. Therefore, it is particularly suitable to use the resin particles as a constituent element of a coating composition.

The above seed polymerization method is a method of absorbing a monomer mixture from a resin seed particle in an aqueous medium and polymerizing the above monomer mixture. In the above seed polymerization method, oil droplets in which the monomer mixture is absorbed in the seed crystal particles are dispersed in an emulsified state in an aqueous medium to prepare an aqueous emulsion, and the monomer mixture is polymerized. The aqueous emulsion can be produced by, for example, a method of treating a mixture of the above monomer mixture and an aqueous medium with a fine emulsifier such as a homogenizer, an ultrasonic processor or a Nanomizer. The above monomer mixture may be added after the seed particles are added to the aqueous medium, or the seed particles may be added to the mixed liquid of the monomer mixture and the aqueous medium.

When the monomer mixture is absorbed by the seed particles, a method of stirring the aqueous latex after adding the seed particles at room temperature (about 20 ° C) for 1 to 12 hours can be usually employed. Further, absorption can be promoted by heating the latex to a temperature of about 30 to 50 °C.

It is preferred to carry out the polymerization reaction by raising the temperature after the seed particles completely absorb the above monomer mixture. It is preferred to carry out polymerization of the above monomer mixture in an aqueous medium by stirring the aqueous monomer emulsion in which the monomer mixture is dispersed in a spherical form. This agitation can be carried out slowly to prevent, for example, the occurrence of floating of the spherical droplets and the sedimentation of the particles after the polymerization.

The composition of the seed crystal particles used in the above-described seed polymerization method is not particularly limited, and examples thereof include styrene resin particles, styrene/butadiene resin particles, and individual polymerization containing a (meth) acrylate monomer. (meth)acrylic resin particles, vinyl acetate resin particles, (meth)acrylic resin particles containing a copolymer of a (meth) acrylate monomer (for example, containing styrene monomer and (a) a group of particles of a copolymer of a propylene monomer). Among them, (meth)acrylic resin particles containing a single polymer or a copolymer of a (meth) acrylate monomer are preferable. Further, the seed particles for seed polymerization are preferably non-crosslinked resin particles, more preferably non-crosslinked (meth) propylene resin particles. As the (meth) acrylate monomer, a compound exemplified as the monofunctional vinyl monomer or the like can be used, and as the styrene monomer, styrene or α-methyl styrene can be used. The seed particles are preferably particles having a volume average particle diameter in the range of 0.1 to 10 μm.

When the monomer mixture is 100 parts by weight, the above seed particles are preferably used in the range of 0.1 to 10 parts by weight, more preferably 0.2 to 5 parts by weight. When the monomer mixture is used in an amount of less than 0.1 part by weight, the monomer mixture is not completely absorbed by the seed particles, and is polymerized by itself in an aqueous medium to form abnormal particles. When the amount of the above-mentioned monomer mixture is more than 10 parts by weight, the amount of the seed crystal particles used is too large, so that the production efficiency is deteriorated, which is not preferable.

The seed particles can be obtained by polymerizing a vinyl monomer, preferably a (meth) acrylate. As the vinyl monomer for obtaining the seed particles, a compound exemplified as the above monofunctional vinyl monomer or the like can be used. The polymerization method of the vinyl monomer for obtaining the seed particles is not particularly limited, but a soap-free polymerization method (emulsion polymerization method without using a surfactant), an emulsion polymerization method, a suspension polymerization method, or a dispersion polymerization can be used. Methods such as methods and seed polymerization methods.

It is also possible to carry out seed polymerization in multiple stages. That is, the seed polymerization may include, for example, the seed polymerization of the first stage, which is obtained by absorbing the monomer mixture into the first seed particles obtained by the polymerization of the amorphous polymerization and polymerizing to obtain the second crystal. Seed particles; and seed polymerization in the final stage, which are obtained by absorbing the monomer mixture into the second seed particles and polymerizing to obtain the crosslinked resin particles of the present invention. Further, the seed crystal polymerization may further include seed crystal polymerization in the first stage, and a second stage seed crystal polymerization of the third seed crystal particles by absorbing the monomer mixture into the second seed crystal particles and polymerizing. ... and seed polymerization of the final stage of obtaining the crosslinked resin particles of the present invention. The method of repeatedly performing seed polymerization in a plurality of stages is suitable for increasing the particle diameter of the resin particles.

As a method of polymerizing the vinyl monomer for obtaining seed crystal particles (first seed particles) for seed crystal polymerization in the first stage, a soap-free polymerization method is preferred. The polymerization of the vinyl monomer for obtaining the seed crystal for the seed polymerization of the first stage can be carried out in the same manner as the polymerization of the above monomer mixture for obtaining the resin particles of the present invention, but it is preferred not to use a surfactant. Further, the polymerization of the vinyl monomer for obtaining the seed particles (the second and subsequent seed particles) for the seed crystal polymerization after the second stage is the same as the seed polymerization of the final stage of obtaining the resin particles of the present invention. For the seed crystal polymerization, it is preferred to use a surfactant, and a dispersion stabilizer may be used as needed.

The resin particles of the present invention preferably have a structure in which the refractive index is in the range of 1.505 to 1.580, and 0.1 g of the resin particles float on the liquid surface of 50 ml of distilled water, so that vortex and turbulence do not occur on the liquid surface. When methanol was dropped onto the above liquid surface under stirring, all the resin particles were wetted with a mixed solution of distilled water and methanol, and completely settled into the above mixed liquid, and the amount of methanol added A (ml) at this time was measured, according to the measured The amount of methanol added A, using the following formula:

Wetability value = {(14.49 × A) + (23.43 × 50)} / (A + 50)

The calculated wettability value is 20.5 (cal/cm ³ ) ^1/2 or more (using the following formula:

Wetability value = {(29.65 × A) + (47.94 × 50)} / (A + 50)

The calculated wettability value was 41.95 (J/cm ³ ) ^1/2 or more).

When the refractive index of the resin particles is less than 1.505 or the refractive index is more than 1.580, when used for an optical film such as an anti-glare film or a light-diffusing resin composition, the wide-angle scattering component which is scattered at a wide angle in the resin particle interface increases. As a result, the front brightness and the front contrast are lowered. On the other hand, since the refractive index of the resin particles having the above-described configuration is in the range of 1.505 to 1.580, the wide-angle scattering component scattered at a wide angle in the resin particle interface is reduced, and as a result, the optical film or the light diffusing resin can be suppressed. The front side brightness and front side contrast of the composition are lowered. In addition, the conventional resin particles having a refractive index in the range of 1.505 to 1.580 are generally low-hydrophilic resin particles such as cross-linked styrene resin particles, and therefore have a low wettability value, but the wettability of the resin particles having the above-described constitution The value is 20.5 (cal/cm ³ ) ^1/2 or more. Therefore, the resin particles having the above-described composition have high dispersibility with respect to other components such as a binder solution, and particularly have high dispersibility for a binder having a hydrophilic functional group such as a hydroxyl group or a binder solution containing an aqueous solvent or the like.

The volume average particle diameter of the resin particles of the present invention is preferably in the range of 0.1 to 5 μm. Therefore, when the resin particles of the present invention are mixed with other components, characteristics such as good light diffusibility and matting can be obtained.

Further, the coefficient of variation of the particle diameter of the resin particles of the present invention is preferably 16% or less. Therefore, when the resin particles of the present invention are mixed with other components, the dispersibility and the dispersion stability are improved, and the properties such as light diffusibility and matting of the resin particles become uniform. The resin particles of the present invention preferably have a volume average particle diameter in the range of 0.1 to 5 μm and a coefficient of variation of the particle diameter of 16% or less.

[Coating composition]

The resin particles of the present invention can be contained in the coating composition as a matting agent for a coating material, a light diffusing agent for an optical diffusion film, a light diffusing agent for an antiglare film, and the like. The composition for coating of the present invention contains the resin particles of the present invention.

The above coating composition may contain a binder resin as needed. As the above binder resin, a resin which is soluble in an organic solvent or water or a latex type water-based resin which can be dispersed in water can be used. Examples of such a binder resin include an acrylic resin, an alkyd resin, a polyester resin, a polyurethane resin, a chlorinated polyolefin resin, an amorphous polyolefin resin, and the like. These binder resins can be appropriately selected depending on the tightness to the substrate of the coating, the use environment, and the like. The amount of the binder resin and the resin particles to be added varies depending on the use, the film thickness of the formed coating film, the average particle diameter of the resin particles, and the coating method.

The above coating composition may contain a solvent as needed. The solvent constituting the composition for a coating layer is not particularly limited, and a solvent capable of dissolving or dispersing the binder resin is preferably used. For example, when the coating composition is an oil-based paint, a hydrocarbon solvent such as toluene or xylene; a ketone solvent such as methyl ethyl ketone or methyl isobutyl ketone; or an ester solvent such as ethyl acetate or n-butyl acetate; ;two An ether solvent such as an alkane, ethylene glycol diethyl ether or ethylene glycol mono-n-butyl ether is used as the above solvent. When the coating composition is an aqueous coating material, an aqueous solvent (aqueous medium) such as water or alcohol can be used as the solvent. These solvents may be used singly or in combination of two or more. The solvent content in the coating composition is usually in the range of 20 to 60% by weight with respect to the total amount of the coating composition.

The coating composition may also contain well-known coating surface conditioners, fluidity regulators, ultraviolet absorbers, light stabilizers, hardening catalysts, extender pigments, coloring pigments, metallic pigments, mica powder pigments, dyes, organics, as needed. Solvents, etc.

The method for forming the coating film using the coating composition is not particularly limited, and any well-known method can be used. Examples of the method for forming the coating film include a spray coating method, a roll coating method, a gravure coating method, a comma coating method, a cast coating method, and a brush coating method. In order to adjust the viscosity as needed, the coating composition may be diluted with a diluent. Examples of the diluent include a hydrocarbon solvent such as toluene or xylene; a ketone solvent such as methyl ethyl ketone or methyl isobutyl ketone; and an ester solvent such as ethyl acetate or butyl acetate; An ether solvent such as an alkane or ethylene glycol diethyl ether; water; an alcohol solvent; These diluents may be used alone or in combination of two or more.

[Optical film]

The optical film of the present invention is obtained by applying the coating composition of the present invention onto a substrate film. The optical film of the present invention can be used as an antiglare film, an optical diffusion film, or the like.

The material of the base film is not particularly limited as long as it is transparent, and examples thereof include polyester resins such as polyethylene terephthalate, triacetone cellulose resin, and polystyrene. Resin, polycarbonate resin, cycloolefin resin, and the like.

The thickness of the above substrate film is preferably in the range of 5 to 300 μm. When the thickness of the base film is less than 5 μm, it is difficult to handle during coating, printing, and secondary processing, and workability is lowered. Further, when the thickness of the base film is more than 300 μm, the visible light transmittance of the base film itself may be lowered.

The optical film of the present invention can be obtained by a method of forming a layer of the coating composition of the present invention on at least one side of a base film by means of coating or the like. Examples of the coating method include a roll coating method, a spray coating method, and the like.

[external agent]

Further, the resin particles of the present invention can also be used as a raw material for an external preparation. The external preparation of the present invention contains the resin particles of the present invention. Although the content of the resin particles in the external preparation can be appropriately set depending on the kind of the external preparation, it is preferably in the range of 1 to 80% by weight, more preferably in the range of 5 to 70% by weight. When the content of the resin particles is less than 1% by weight based on the total amount of the external preparation, it is difficult to confirm the remarkable effect of the resin particles. Further, if the content of the resin particles is more than 80% by weight, a remarkable effect corresponding to an increase in the content cannot be exhibited, and thus it is not preferable in terms of production cost.

Examples of the external preparation include a cosmetic material, a pharmaceutical for external use, and the like.

The cosmetic material is not particularly limited as long as it is obtained by containing the resin particles, and examples thereof include a men's shaving liquid, a body lotion, a lotion, an emulsion, an emulsion, a body wash, an antiperspirant, and the like. Liquid cosmetic materials; cosmetics for washing soaps, facial scrubs, etc.; moisturizing creams; emulsions for shaving; powders; foundation creams; lipsticks; lip balms; rouge; eyebrow cosmetics; nail cosmetics; Cosmetics; hair dye materials; hairdressing materials; aromatic cosmetics; toothbrushes; bathing agents; sunscreen products; sunbathing products; body powder, baby powder and other body cosmetics.

The above-mentioned external pharmaceutical preparation is not particularly limited as long as it is suitable for the skin, and examples thereof include a pharmaceutical emulsion, an ointment, a pharmaceutical emulsion, and a pharmaceutical lotion.

Further, in the range which does not impair the effects of the present invention, a main agent or an additive which is generally used may be blended in these external preparations depending on the purpose. Examples of such a main agent or an additive include water, a lower alcohol (an alcohol having 5 or less carbon atoms), fats and oils, a wax, a hydrocarbon, a higher fatty acid (a fatty acid having 12 or more carbon atoms), and a higher alcohol (carbon). Alcohol with 6 or more atoms), sterols, fatty acid esters (ethyl 2-hexadecane, etc.), metal soaps, humectants, surfactants (sorbitan sesquioleate, etc.) , polymer compounds, clay minerals (both physical pigments and adsorbents and other functional components; talc, mica, etc.), color materials (titanium oxide, red iron oxide, yellow iron oxide, black iron oxide, etc.), spices Other anti-corrosive fungicides, antioxidants, ultraviolet absorbers, cerium particles, polystyrene particles, and other resin particles, and special blends.

[Light diffusing resin composition]

By dispersing the resin particles of the present invention in a transparent base resin (transparent resin), it can be used as a raw material (light-diffusing resin composition) of an optical member such as a light-diffusing sheet of a lighting cover or a liquid crystal display device. The light diffusing resin composition of the present invention contains the resin particles of the present invention and a transparent substrate resin.

As the transparent base resin, a thermoplastic resin is usually used. Examples of the thermoplastic resin include (meth)acrylic resin such as polymethyl methacrylate, alkyl (meth)acrylate-styrene copolymer, polycarbonate, polyester, polyethylene, polypropylene, and poly. Styrene and the like. When excellent transparency is required, among these thermoplastic resins, (meth) propylene resin, (meth)acrylic propylene-styrene copolymer, polycarbonate, polyester, and polystyrene are preferable. These thermoplastic resins may be used singly or in combination of two or more.

The addition ratio of the resin particles to the transparent base resin is preferably 0.01 to 100 parts by weight of the resin particles when the transparent base resin is 100 parts by weight. Therefore, it is possible to have good light diffusibility and light transmittance. When the amount of the transparent base resin is 100 parts by weight, the resin particles are less than 0.01 parts by weight, and it is difficult to have light diffusibility. When the amount of the transparent base resin is 100 parts by weight, when the resin particles exceed 100 parts by weight, light diffusibility can be obtained, but light transmittance is lowered. More preferably, the resin particles are added in an amount of from 0.1 to 10 parts by weight based on 100 parts by weight of the transparent base resin.

The method for producing the light-diffusing resin composition is not particularly limited, and the resin particles and the transparent base resin of the present invention may be mixed by a mixing method such as a mechanical pulverization mixing method to produce a light-diffusing resin composition. In the mechanical pulverization mixing method, the resin particles and the transparent substrate resin of the present invention can be mixed and stirred by using, for example, a Henschel mixer, a V-type mixer, a drum mixer, a mixer, a roll mixer, or the like. A light diffusing resin composition is produced.

A light-diffusing resin molded article such as a light-diffusing resin molded sheet (optical sheet) can be produced by forming a light-diffusing resin composition. For example, the resin particles and the transparent base material resin of the present invention are mixed by a mixer, and kneaded by a melt kneader such as an extruder to obtain particles containing the light diffusing resin composition, and then the particles are obtained. After extrusion molding or melt-molding, it is possible to obtain a light-diffusing resin molded body having an arbitrary shape.

The light-diffusing resin molded body can be used, for example, as a lighting cover for a light-emitting diode (LED) illumination, a lighting cover such as a fluorescent lighting cover, a light diffusing plate of a liquid crystal display device, or the like. The configuration of the liquid crystal display device is not particularly limited as long as it contains a light diffusing plate (light diffusing resin molded body). For example, the liquid crystal display device has at least a liquid crystal display panel including a display surface and an inner surface, a light guide plate disposed on the inner surface side of the panel, and a light source that allows light to enter the side surface of the light guide plate. Further, the liquid crystal display device has a light diffusing plate on a surface of the light guiding plate facing the liquid crystal display panel, and a reflecting sheet on the side opposite to the surface of the light guiding plate facing the liquid crystal display panel. Further, a reflection sheet is provided on the opposite surface and the opposite surface side of the light guide plate and the liquid crystal display panel. The configuration of the light source is generally referred to as an edge-lit backlight configuration. As the arrangement of the light sources in the liquid crystal display device, in addition to the above-described sidelight type backlight arrangement, there is also a direct type backlight arrangement. Specifically, the arrangement is such that a light source is disposed on the inner surface side of the liquid crystal display panel, and at least a light diffusion plate disposed between the liquid crystal display panel and the light source is provided.

Example

The present invention will be further specifically described below based on examples, but the present invention is not limited to the examples. In the following examples and comparative examples, the method for measuring the volume average particle diameter of the seed particles, the method for measuring the volume average particle diameter of the resin particles and the coefficient of variation of the particle diameter, the method for measuring the wettability value of the resin particles, and the coating method The evaluation method of the dispersibility of the resin particles in the layer composition is as follows.

[Method for Measuring Volume Average Particle Diameter of Seed Particles]

0.1 g of the seed crystal particles and 10 ml of a 0.1% by weight aqueous solution of the nonionic surfactant were placed in a test tube, and they were mixed by a contact stirrer (trade name "TOUCHMIXER MT-31", manufactured by YAMATO Scientific Co., Ltd.) for 2 seconds. Then, the seed crystal particles in the test tube were pre-dispersed in the above aqueous solution for 10 minutes using a commercially available ultrasonic cleaner (trade name "ULTRA SONIC CLEANER VS-150", manufactured by VELVO-CLEAR Co., Ltd.) to obtain a dispersion liquid. The obtained dispersion liquid was irradiated with ultrasonic waves, and the volume average particle diameter of the seed crystal particles contained in the obtained dispersion liquid was measured using a laser diffraction type particle size distribution measuring apparatus (model "LS230", manufactured by Beckman Coulter Co., Ltd.). (Arithmetic mean diameter of the volume-based particle size distribution). The optical model used to calculate the volume average particle diameter in the laser diffraction type particle size distribution measuring apparatus was adjusted to the refractive index of the seed crystal to be produced.

[Method for Measuring Volume Average Particle Diameter of Resin Particles and Variation Coefficient of Particle Diameter]

According to Reference MANUAL FOR THE COULTER MULTISIZER (1987) issued by Coulter Electronics Limited, a Coulter-type precise particle size distribution measuring apparatus (trade name) is used using an aperture having a size (diameter) of X μm suitable for the particle diameter of the particles to be measured. The collation of "coulter Multisizer III" and Beckman Coulter Co., Ltd. was used to measure the volume average particle diameter and CV value of the resin particles by the Coulter type precise particle size distribution measuring apparatus.

With respect to the resin particles having an average particle diameter of less than 1 μm, the pore size X μm is 20 μm, and the resin particles having a pore size of X μm is 50 μm with respect to the resin particles of 1 μm or more and less than 10 μm, and the resin particles having an average particle diameter of 10 μm or more and less than 30 μm. The resin particle having a size of X μm of 100 μm and having an average particle diameter of 30 μm or more and less than 90 μm has a pore size X μm of 280 μm, and the pore size X μm is 400 μm with respect to the resin particles having an average particle diameter of more than 90 μm.

Specifically, 0.1 g of the resin particles was placed in 10 ml of a 0.1% by weight aqueous solution of a nonionic surfactant, and pre-dispersed by a contact stirrer (trade name "TOUCHMIXER MT-31", manufactured by YAMATO Scientific Co., Ltd.) and ultrasonic waves. , to obtain a dispersion. Then, the dispersion was dripped with a dropper while slowly stirring in a beaker filled with a measurement electrolyte solution ("ISOTON (registered trademark) II", manufactured by Beckman Coulter Co., Ltd.) attached to the main body of the measurement device. The reading of the densitometer on the main screen of the above measuring device is adjusted to about 10%. Next, an aperture size X μm is provided on the main body of the measuring apparatus, and Current (cell current), Gain (gain), and Polarity (polarity of the inner electrode) are set to specified conditions of the corresponding aperture sizes, and the volume average particle diameter and volume reference are measured. The standard deviation of the particle size distribution. During the measurement, the bubbles were slowly stirred so as not to allow the bubbles to enter the beaker, and the measurement was terminated when 100,000 resin particles were measured. As the volume average particle diameter of the resin particles, the arithmetic mean diameter (arithmetic mean diameter of the volume % mode) of the volume-based particle size distribution was calculated.

Based on the above-described standard deviation (σ) and the above average particle diameter (D), the coefficient of variation (CV value) of the particle diameter of the resin particles was calculated by the following formula.

CV value (%) = (σ / D) × 100

[Method for Measuring Moisture Value of Resin Particles]

First, 0.1 g of resin particles were spread on a liquid surface of 50 ml of distilled water in a 100 ml glass beaker (having an inner diameter of about 50 mm), and the resin particles were floated on the liquid surface. Next, using a stir bar having a length of 30 mm, the liquid in the glass beaker was slowly stirred by a magnetic stirrer at a speed of about 500 rpm without causing vortex and turbulence on the liquid surface, and methanol was dropped to the above liquid. surface. The amount of methanol added A (ml) at this time was measured by the time when all the resin particles were wetted by the above liquid (mixed liquid of distilled water and methanol) and completely settled into the above liquid. The methanol addition amount A was brought into the following formula, and the wettability value [(cal/cm ³ ) ^1/2 or (J/cm ³ ) ^1/2 ] was calculated. This wettability value corresponds to the solubility parameter value of the above liquid when all the resin particles are completely settled into the above liquid. Therefore, the large wettability value of the resin particles means that the resin particles have high wettability with respect to an aqueous solvent such as water.

Wetability value [(cal/cm ³ ) ^1/2 ]={(14.49×A)+(23.43×50)}/(A+50)

Wetability value [(J/cm ³ ) ^1/2 ]={(29.65×A)+(47.94×50)}/(A+50)

Soluble parameter value of methanol = 14.49 (cal / cm ³ ) ^1/2 = 29.65 (J / cm ³ ) ^1/2

Water solubility parameter value = 23.43 (cal / cm ³ ) ^1/2 = 47.94 (J / cm ³ ) ^1/2

[Method for Evaluating Dispersibility of Resin Particles in Coating Composition]

50 parts by weight of dipentaerythritol hexaacrylate (trade name "KAYARADDPHA", manufactured by Nippon Kayaku Co., Ltd.), 10 parts by weight of resin particles, and an ultraviolet polymerization initiator (trade name "Irgacure 184", manufactured by Ciba Specialty Chemicals Co., Ltd.) 6 parts by weight, 30 parts by weight of cyclohexanone, 90 parts by weight of n-butyl alcohol, and 30 parts by weight of isopropyl alcohol were obtained. The obtained complex was dispersed by a rotation autoclave (manufactured by THINKY Co., Ltd.) for 5 minutes to obtain a coating composition.

A part of the coating composition was placed on the objective glass slide, and the composition for the coating was covered with a glass cover, and the dispersion state of the resin particles in the coating composition was confirmed by a microscope (manufactured by KEYENCE Co., Ltd.). Then, when the resin particles were not aggregated, the dispersibility of the resin particles in the coating composition was evaluated to be good, and when the resin particles were aggregated, the dispersibility of the resin particles in the coating composition was evaluated as poor.

[Example 1] (Manufacture of seed particles)

First, 200 g of methyl methacrylate and 3 g of n-octyl thiol as a chain transfer agent were mixed to prepare a monomer mixture. Further, 1 g of potassium persulfate as a polymerization initiator was dissolved in 19 g of deionized water as an aqueous medium to obtain 20 g of an aqueous potassium persulfate solution.

1000 g of deionized water as an aqueous medium was placed in a polymerization vessel equipped with a stirrer and a thermometer, and the monomer mixture was supplied to the above-mentioned polymerizer, and the air in the polymerization vessel was replaced with nitrogen, and the agitator was stirred by the above-mentioned agitator. The contents were raised to 55 ° C while the internal temperature of the above polymerization vessel was raised. Then, while the above stirring was continued, and 20 g of the potassium persulfate aqueous solution as a polymerization initiator was added to the content of the polymerization vessel while maintaining the internal temperature of the polymerization vessel at 55 ° C, polymerization was carried out for 20 hours. In this way, a latex containing seed particles is obtained. The seed particles contained in the obtained latex had a volume average particle diameter of 0.6 μm.

(Manufacture of resin particles)

Next, 8 g of sodium dodecylbenzenesulfonate as a surfactant was dissolved in 1492 g of ion-exchanged water as an aqueous medium, and 1500 g of a surfactant aqueous solution was prepared. Further, 400 g of styrene as a styrene monomer (monofunctional vinyl monomer), and alkyl (meth)acrylate having 1 to 4 carbon atoms as an alkyl group (monofunctional vinyl type) are mixed. 300 g of methyl methacrylate, 300 g of ethylene glycol dimethacrylate as a crosslinkable monomer, and poly(ethylene glycol-propylene glycol) monomethyl as a hydrophilic monofunctional (meth) acrylate A acrylate (manufactured by Nippon Oil Co., Ltd., trade name "Brenmar (registered trademark) 70PEP-350B", a mixture of a plurality of compounds represented by the above formula (1), that is, R ₁ is CH ₃ , m is about average 5, n is about 2 on average, R ₂ is H) 10 g (when the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, it is 1.0 part by weight), and as a polymerization initiator 10 g of 2,2'-azobisisobutyronitrile was prepared to prepare a monomer mixture.

Then, the monomer mixture liquid was placed in 1500 g of the aqueous surfactant solution, and the mixture obtained by stirring at a speed of 9000 rpm by a high-speed emulsification disperser (trade name "TK Homomixer Mark II 2.5", manufactured by PRIMIX Co., Ltd.) was used. The solution was allowed to stand for 10 minutes to obtain an emulsion.

The emulsion was placed in a polymerization vessel equipped with a stirrer and a thermometer, and 40 g of the latex containing the seed crystal particles produced above was placed in the above emulsion to absorb the monomer mixture into the seed particles. Then, the contents of the above polymerization vessel were stirred at 30 ° C for 5 hours to obtain a dispersion. 3500 g of a 5 wt% aqueous solution of polyvinyl alcohol ("Gohsenol (registered trademark) GH-17" manufactured by Nippon Synthetic Chemical Co., Ltd.) as a dispersion stabilizer was added to the dispersion. Then, resin particles were obtained by polymerizing the monomer mixture in the dispersion at 70 ° C for 10 hours.

The obtained resin particles had a volume average particle diameter of 3.0 μm and a coefficient of variation (CV value) of the particle diameter of 10.2%. Further, the obtained resin particles had a refractive index of 1.535 and a wettability value of 21.3 (cal/cm ³ ) ^1/2 (43.6 (J/cm ³ ) ^1/2 ).

In addition, when the dispersion state of the resin particles in the coating composition is confirmed by the above-described evaluation method, as shown in Fig. 1, the resin particles are well dispersed without agglomeration, and therefore the dispersibility of the resin particles in the coating composition is obtained. For the good.

[Example 2] (Production Example of Resin Particles)

First, 5 g of sodium dioctyl succinate sulfonate as a surfactant was dissolved in 1495 g of ion-exchanged water as an aqueous medium, and 1500 g of an aqueous surfactant solution was prepared. Further, 600 g of styrene, 600 g of α-methylstyrene, and 120 g of methyl methacrylate as an alkyl (meth)acrylic acid alkyl ester having 1 to 4 alkyl groups as a styrene monomer are added. 100 g of divinylbenzene as a crosslinkable monomer, poly(ethylene glycol-propylene glycol) monomethacrylate as a hydrophilic monofunctional (meth) acrylate (manufactured by Nippon Oil Co., Ltd., "Brenmar ( The registered trademark) 50PEP-300", a mixture of a plurality of compounds represented by the above formula (1), that is, R ₁ is CH ₃ , m has an average of about 3.5, n has an average of about 2.5, and R ₂ is H) 150 g (single When the total amount of the functional vinyl monomer and the crosslinkable monomer is 100 parts by weight, it is 18 parts by weight, and 10 g of 2,2'-azobisisobutyronitrile as a polymerization initiator is prepared into a single Body mixture.

Then, the monomer mixture liquid was placed in 1500 g of the aqueous surfactant solution, and the mixture obtained by stirring at a speed of 9000 rpm by a high-speed emulsification disperser (trade name "TK Homomixer Mark II 2.5", manufactured by PRIMIX Co., Ltd.) was used. The solution was allowed to stand for 10 minutes to obtain an emulsion.

First, the emulsion was placed in a polymerization machine equipped with a stirrer and a thermometer, and 40 g of the latex containing the seed particles produced in Example 1 was placed in the above emulsion to absorb the monomer mixture into the seed particles. Then, the contents of the above polymerization vessel were stirred at 30 ° C for 5 hours to obtain a dispersion. 3500 g of a 5 wt% aqueous solution of polyvinyl alcohol ("Gohsenol (registered trademark) GH-17" manufactured by Nippon Synthetic Chemical Co., Ltd.) as a dispersion stabilizer was added to the dispersion. Then, resin particles were obtained by polymerizing the monomer mixture in the dispersion at 70 ° C for 10 hours.

The obtained resin particles had a volume average particle diameter of 2.9 μm and a coefficient of variation (CV value) of the particle diameter of 12.5%. Further, the obtained resin particles had a refractive index of 1.570 and a wettability value of 22.6 (cal/cm ³ ) ^1/2 (46.2 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. For the good.

[Example 3] (Production Example of Resin Particles)

First, 5 g of sodium dodecylbenzenesulfonate as a surfactant was dissolved in 1495 g of ion-exchanged water as an aqueous medium, and 1500 g of a surfactant aqueous solution was prepared. Further, 100 g of styrene as a styrene monomer, 700 g of methyl methacrylate as an alkyl (meth)acrylic acid alkyl group having 1 to 4 alkyl groups, and 1 as a crosslinkable monomer are mixed. 200 g of 6-hexanediol dimethacrylate, and polypropylene glycol monomethacrylate which is a hydrophilic monofunctional (meth)acrylate (manufactured by Nippon Oil Co., Ltd., trade name "Brenmar (registered trademark) PP) -1000", a mixture of a plurality of compounds represented by the above formula (1), that is, R ₁ is CH ₃ , m is 0, n is about 4 to 6 on average, and R ₂ is H) 10 g (monofunctional vinyl) When the total amount of the monomer and the crosslinkable monomer is 100 parts by weight, it is 1.0 part by weight), and 10 g of 2,2'-azobisisobutyronitrile as a polymerization initiator is prepared to prepare a monomer mixture.

Then, the monomer mixture liquid was placed in 1500 g of the aqueous surfactant solution, and the mixture obtained by stirring at a speed of 9000 rpm by a high-speed emulsification disperser (trade name "TKHomomixer Mark II 2.5", manufactured by PRIMIX Co., Ltd.) was used. The solution was allowed to stand for 10 minutes to obtain an emulsion.

The emulsion was placed in a polymerization vessel equipped with a stirrer and a thermometer, and 300 g of the latex containing the seed particles produced in Example 1 was added to the above emulsion to absorb the monomer mixture into the seed particles. Then, the contents of the above polymerization vessel were stirred at 30 ° C for 2 hours to obtain a dispersion. In the dispersion 4,000 g of a 5% by weight aqueous solution of polyvinyl alcohol ("Gohsenol (registered trademark) GH-17" manufactured by Nippon Synthetic Chemical Co., Ltd.) was added as a dispersion stabilizer. Then, resin particles were obtained by polymerizing the monomer mixture in the dispersion at 70 ° C for 10 hours.

The obtained resin particles had a volume average particle diameter of 1.4 μm and a coefficient of variation (CV value) of the particle diameter of 15.6%. Further, the obtained resin particles had a refractive index of 1.505 and a wettability value of 22.8 (cal/cm ³ ) ^1/2 (46.7 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. For the good.

[Example 4] (Production Example of Resin Particles)

First, 5 g of sodium dodecylbenzenesulfonate as a surfactant was dissolved in 1495 g of ion-exchanged water as an aqueous medium, and 1500 g of a surfactant aqueous solution was prepared. Further, 550 g of styrene as a styrene monomer, 300 g of butyl methacrylate as an alkyl (meth)acrylic acid alkyl group having 1 to 4 alkyl groups, and B as a crosslinkable monomer are mixed. 50 g of diol dimethacrylate, and polypropylene glycol monomethacrylate which is a hydrophilic monofunctional (meth) acrylate (manufactured by Nippon Oil Co., Ltd., trade name "Brenmar (registered trademark) PP-1000") 100 g (11 parts by weight when the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight), and 10 g of 2,2'-azobisisobutyronitrile as a polymerization initiator, Prepared into a monomer mixture.

Then, the monomer mixture liquid was placed in 1500 g of the aqueous surfactant solution, and the mixture obtained by stirring at a speed of 9000 rpm by a high-speed emulsification disperser (trade name "TKHomomixer Mark II 2.5", manufactured by PRIMIX Co., Ltd.) was used. The solution was allowed to stand for 10 minutes to obtain an emulsion.

The emulsion was placed in a polymerization vessel equipped with a stirrer and a thermometer, and 20 g of the latex containing the seed particles produced in Example 1 was placed in the above emulsion to absorb the monomer mixture into the seed particles. Then, the contents of the above polymerization vessel were stirred at 30 ° C for 5 hours to obtain a dispersion. 3500 g of a 5 wt% aqueous solution of polyvinyl alcohol ("Gohsenol (registered trademark) GH-17" manufactured by Nippon Synthetic Chemical Co., Ltd.) as a dispersion stabilizer was added to the dispersion. Then, resin particles were obtained by polymerizing the monomer mixture in the dispersion at 70 ° C for 10 hours.

The obtained resin particles had a volume average particle diameter of 4.0 μm and a coefficient of variation (CV value) of the particle diameter of 11.2%. Further, the obtained resin particles had a refractive index of 1.550 and a wettability value of 21.8 (cal/cm ³ ) ^1/2 (44.6 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. For the good.

[Example 5] (Production Example of Resin Particles)

First, 5 g of sodium dodecylbenzenesulfonate as a surfactant was dissolved in 1495 g of ion-exchanged water as an aqueous medium, and 1500 g of a surfactant aqueous solution was prepared. Further, 30 g of styrene as a styrene monomer, 800 g of butyl methacrylate having an alkyl group having 1 to 4 alkyl (meth)acrylate, and 2 as a crosslinkable monomer are mixed. 120 g of vinyl benzene, poly(ethylene glycol-propylene glycol) monomethacrylate (manufactured by Nippon Oil Co., Ltd., trade name "Brenmar 50PEP-300") as a hydrophilic monofunctional (meth) acrylate 50 g ( When the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, it is 5.3 parts by weight, and 10 g of 2,2'-azobisisobutyronitrile as a polymerization initiator is prepared. Monomer mixture.

Then, the monomer mixture liquid was placed in 1500 g of the aqueous surfactant solution, and the mixture obtained by stirring at a speed of 9000 rpm by a high-speed emulsification disperser (trade name "TK Homomixer Mark II 2.5", manufactured by PRIMIX Co., Ltd.) was used. The solution was allowed to stand for 10 minutes to obtain an emulsion.

The emulsion was placed in a polymerization vessel equipped with a stirrer and a thermometer, and 20 g of the latex containing the seed particles produced in Example 1 was placed in the above emulsion to absorb the monomer mixture into the seed particles. Then, the contents of the above polymerization vessel were stirred at 30 ° C for 5 hours to obtain a dispersion. 3500 g of a 5 wt% aqueous solution of polyvinyl alcohol ("Gohsenol (registered trademark) GH-17" manufactured by Nippon Synthetic Chemical Co., Ltd.) as a dispersion stabilizer was added to the dispersion. Then, resin particles were obtained by polymerizing the monomer mixture in the dispersion at 70 ° C for 10 hours.

The obtained resin particles had a volume average particle diameter of 4.0 μm and a coefficient of variation (CV value) of the particle diameter of 11.8%. Further, the obtained resin particles had a refractive index of 1.510 and a wettability value of 22.5 (cal/cm ³ ) ^1/2 (46.0 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. For the good.

[Example 6] (Production Example of Resin Particles)

In addition to the addition amount of poly(ethylene glycol-propylene glycol) monomethacrylate (trade name "Brenmar70PEP-350B", manufactured by Nippon Oil Co., Ltd.) was changed to 50 g (monofunctional vinyl monomer and crosslinkable single) Resin particles were obtained in the same manner as in Example 1 except that the total amount of the particles was 5.0 parts by weight, which was 5.0 parts by weight.

The obtained resin particles had a volume average particle diameter of 3.0 μm and a coefficient of variation (CV value) of the particle diameter of 11.5%. Further, the obtained resin particles had a refractive index of 1.535 and a wettability value of 21.7 (cal/cm ³ ) ^1/2 (44.4 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. For the good.

[Comparative Example 1] (Production Example of Resin Particles)

In addition to the addition amount of poly(ethylene glycol-propylene glycol) monomethacrylate (manufactured by Nippon Oil Co., Ltd., trade name "Brenmar (registered trademark) 70PEP-350B") to 0.5 g (monofunctional vinyl type) Resin particles were obtained in the same manner as in Example 1 except that the total amount of the bulk and crosslinkable monomers was 0.05 parts by weight.

The obtained resin particles had a volume average particle diameter of 3.0 μm and a coefficient of variation (CV value) of the particle diameter of 11.1%. Further, the obtained resin particles had a refractive index of 1.535 and a wettability value of 20.2 (cal/cm ³ ) ^1/2 (41.3 (J/cm ³ ) ^1/2 ).

In addition, when the dispersion state of the resin particles in the coating composition is confirmed by the above-described evaluation method, as shown in Fig. 2, the resin particles are aggregated, so that the dispersibility of the resin particles in the coating composition is poor.

[Comparative Example 2] (Test example for producing resin particles)

In addition to the addition amount of poly(ethylene glycol-propylene glycol) monomethacrylate (manufactured by Nippon Oil Co., Ltd., trade name "Brenmar (registered trademark) 70PEP-350B") to 400 g (monofunctional vinyl monomer) The resin particles were tried in the same manner as in Example 1 except that the total amount of the crosslinkable monomers was 100 parts by weight, which was 40 parts by weight. As a result, the polymer aggregated and aggregated during the polymerization, and the resin particles could not be obtained.

[Comparative Example 3] (Production Example of Resin Particles)

In addition to using 10 g of 2-hydroxyethyl methacrylate (trade name "Light Ester HOB", manufactured by Kyoeisha Chemical Co., Ltd.) instead of poly(ethylene glycol-propylene glycol) monomethacrylate (made by Nippon Oil Co., Ltd.) Resin particles were obtained in the same manner as in Example 1 except for the trade name "Brenmar (registered trademark) 70PEP-350B".

The obtained resin particles had a volume average particle diameter of 3.0 μm and a coefficient of variation (CV value) of the particle diameter of 11.7%. Further, the obtained resin particles had a refractive index of 1.535 and a wettability value of 21.0 (cal/cm ³ ) ^1/2 (43.0 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. Bad (aggregation occurs).

[Comparative Example 4] (Production Example of Resin Particles)

Resin particles were obtained in the same manner as in Example 1 except that poly(ethylene glycol-propylene glycol) monomethacrylate (trade name "Brenmar (registered trademark) 70PEP-350B") was not added. .

The obtained resin particles had a volume average particle diameter of 3.0 μm and a coefficient of variation (CV value) of the particle diameter of 10.2%. Further, the obtained resin particles had a refractive index of 1.535 and a wettability value of 20.1 (cal/cm ³ ) ^1/2 (41.1 (J/cm ³ ) ^1/2 ), and dispersibility in the coating composition. Bad (aggregation occurs).

[Comparative Example 5] (Test example for producing resin particles)

In addition to the compound represented by the above formula (1), hydroxyethyl 2-methacrylate (wherein R ₁ is CH ₃ , m = 1, n = 0, and R ₂ is H) (trade name, manufactured by Mitsubishi Rayon Co., Ltd.) "ACRYESTERHO") 100 g is the same as that of Example 1 except that 10 g of poly(ethylene glycol-propylene glycol) monomethacrylate (trade name "Brenmar (registered trademark) 70PEP-350B"). The method obtains resin particles. As a result, the polymer aggregated and aggregated during the polymerization, and the resin particles could not be obtained.

The refractive index, volume average particle diameter, and dispersibility in the coating composition of the resin particles obtained in Examples 1 to 6 and Comparative Examples 1 to 5 are collectively shown in Table 1.

From the comparison of Examples 1 to 6 and Comparative Examples 1 to 5, it was found that the dispersibility in the coating composition of the resin particles of the present invention was good.

[Example 7] (Production Example of Coating Composition)

First, 100 parts by weight of a mixture of pentaerythritol triacrylate and pentaerythritol tetraacrylate (KAYARADPET-30, manufactured by Nippon Kayaku Co., Ltd.) as a binder resin, 15 parts by weight of the resin particles produced in Example 1, and ultraviolet polymerization were mixed. 6 parts by weight of an initiator (Irgacure 184, manufactured by Ciba Specialty Chemicals Co., Ltd.) and 140 parts by weight of toluene as a solvent were obtained to obtain a mixture. The mixture was dispersed by a sand mill for 30 minutes to obtain a composition for forming a light-diffusing layer as a coating composition.

[Example 8] (Production Example of Antiglare Film)

The composition for forming a light-diffusing layer obtained in Example 7 was coated on one side of a TAC (triethyl fluorene cellulose) film having a thickness of 80 μm by a gravure trans-coating method, and dried at 100 ° C for 2 minutes. Then, the coating film was irradiated with ultraviolet rays by a 120 W/cm concentrating high-pressure mercury lamp, and a light diffusion layer having a layer thickness of 6 μm as an optical film was obtained by curing the coating film (by forming a composition for forming a light diffusion layer) An anti-glare film of a coating film formed by hardening of a substance.

[Example 9] (Production Example of External Agent)

In this example, a foundation cream containing a powder portion and an oil portion was produced. In other words, first, 21 g of the resin particles obtained in Example 1, 38 g of talc as a clay mineral, 22 g of mica as a clay mineral, and 6 g of titanium oxide as a raw material of a color material were mixed by a Henschel mixer. 0.6 g of red iron oxide as a raw material, 1 g of yellow iron oxide as a raw material of a color material, and 0.1 g of black iron oxide as a raw material of a color material were prepared into the above-mentioned powder part. Further, 10 g of ethyl 2-hexadecane as a fatty acid ester, 1 g of sesquioleic acid sorbitan anhydride as a surfactant, and 0.2 g of a preservative were mixed and dissolved to prepare an oil portion (without fragrance).

Next, the above oil portion (without fragrance) was added to the above powder portion and uniformly mixed. Further, after 0.1 g of the perfume was added to and mixed with the obtained mixture, the obtained mixture was pulverized and passed through a sieve. The mixture passing through the sieve was compression-molded to obtain a foundation cream as an external preparation.

Fig. 1 is a micrograph showing the state of dispersion of the resin particles of Example 1 in the coating composition.

Fig. 2 is a photomicrograph showing the state of dispersion of the resin particles of Comparative Example 1 in the composition for coating.

Since the picture in this case is a photo, it is not a representative figure of this case.

Therefore, there is no designated representative map in this case.

Claims (14)

A resin particle obtained by polymerizing a monomer mixture having an oxygen-extended ethyl chain having a chain length of 1 to 50 and an oxygen-extended propyl chain having a chain length of 1 to 50 in an aqueous medium a monofunctional (meth) acrylate of at least one of the above, a monofunctional vinyl monomer other than the monofunctional (meth) acrylate, and a crosslinkable monomer, and a chain length of the above oxygen extended ethyl chain When the total length of the chain of the above-mentioned oxygen-extended propyl chain is 2 or more, and the total amount of the monofunctional vinyl monomer and the crosslinkable monomer is 100 parts by weight, the monofunctional (meth) acrylate The amount is in the range of 0.1 to 20 parts by weight. The resin particle according to claim 1, wherein the monofunctional (meth) acrylate is represented by the following formula (1); (wherein R ₁ represents H or CH ₃ , m is a number from 1 to 50, n is a number from 1 to 50 (wherein the total of m and n is 2 or more), and R ₂ represents H or CH ₃ ). The resin particles according to claim 1, wherein the refractive index is from 1.505 to 1.580. The resin particles according to claim 1, wherein the refractive index is in the range of 1.505 to 1.580, and 0.1 g of the resin particles are floated on the liquid surface of 50 ml of distilled water, so that vortex does not occur on the liquid surface. Under the stirring of a turbulent degree, when methanol is dropped onto the above liquid surface, all the resin particles are wetted by the mixed solution of distilled water and methanol and completely settled into the above mixed liquid, and the amount of methanol added A (ml) at this time is measured, according to The measured methanol addition amount A was calculated according to the following formula: wettability value = {(14.49 × A) + (23.43 × 50)} / (A + 50) The wettability value was 20.5 (cal / cm ³ ) ^1/2 or more. The resin particle according to claim 1, wherein the monofunctional vinyl monomer is an alkyl (meth)acrylic acid alkyl group having an alkyl group of 1 to 4 and is selected from the group consisting of styrene and α. a mixture of at least one styrene monomer in the group consisting of -methylstyrene. The resin particle according to claim 1, wherein the crosslinkable monomer is selected from the group consisting of ethylene glycol dimethacrylate, 1,6-hexanediol dimethacrylate, and divinyl. At least one monomer of the group consisting of benzene. The resin particle according to claim 1, wherein the monomer mixture is obtained by a seed polymerization method in which the monomer mixture absorbs seed crystal particles composed of a resin and polymerizes the monomer mixture. The resin particles according to claim 1, wherein the volume average particle diameter is in the range of 0.1 to 5 μm, and the coefficient of variation of the particle diameter is 16% or less. A coating composition comprising the resin particles according to any one of claims 1 to 8. An optical film obtained by applying the coating composition according to claim 9 of the invention to a substrate film. The optical film of claim 10, wherein the optical film is an anti-glare film. A cosmetic material comprising the resin particles according to any one of claims 1 to 8. A pharmaceutical composition according to any one of claims 1 to 8, wherein the resin particles according to any one of claims 1 to 8. A light-diffusing resin composition containing a transparent base resin and the resin particles according to any one of claims 1 to 8.