JP6134592B2 - Resin particle solvent dispersion and use thereof - Google Patents

Description

  The present invention is a resin particle solvent dispersion comprising an organic solvent and resin particles dispersed in the organic solvent, and is used for anti-reflection of a film such as a light diffusion film or an antiglare film used for a flat panel display or the like. The present invention relates to a resin particle solvent dispersion suitably used for a blocking agent and its use (paint).

  A film such as a light diffusing film or an antiglare film used for a flat panel display is usually one side of a base material layer (thin layer film) based on a resin such as polyethylene terephthalate (hereinafter abbreviated as “PET”). On the top or both sides, a laminated film is formed by forming a hard coat layer for preventing the film from being scratched by coating or the like. Since a laminated film formed by forming a hard coat layer on one side or both sides of such a thin layer film is usually stored in multiple rolls, the laminated film of the outer part is laminated on the laminated film of the inner part. And the hard coat layer of the laminated film of one part of the inner part and the outer part comes into contact with the base material layer or the hard coat layer of the laminated film of the other part. At that time, between the hard coat layer and the hard coat layer, or between the hard coat layer and the base material layer, an adhesive force or a chemical adhesive force acts, so that the laminated film of the outer part becomes the laminated film of the inner part. It may be in an attached state and it may be difficult to peel the laminated film of the outer part from the laminated film of the inner part. Such a phenomenon that the surfaces of the laminated films adhere to each other is called blocking.

  In order to prevent blocking between the surfaces of the laminated films provided with such a hard coat layer, inorganic fine particles having a particle diameter of 1 μm or less made of an inorganic substance such as mica, synthetic mica, silica, alumina, and titania are kneaded in the hard coat paint. There is a technique for forming a hard coat layer containing inorganic fine particles by applying a coating material on the base material layer. Thereby, irregularities derived from the inorganic fine particles are formed on the surface of the hard coat layer, and the contact area between the hard coat layer and the hard coat layer or between the hard coat layer and the base material layer becomes small. Blocking can be prevented. In the above technique, the inorganic fine particles in the hard coat layer function as an antiblocking agent.

  As the above technique, for example, in Patent Document 1, a hard coat layer containing inorganic fine particles, particularly inorganic fine particles having an average particle diameter of 10 to 300 nm and having at least one of a scaly shape and an irregular flake shape is a base material. A hard coat film formed thereon is disclosed.

JP 2004-042653 A

  However, when inorganic fine particles are used as an anti-blocking agent and added to the hard coat layer of the laminated film, the laminated film is wound in multiple rolls so that the hard coat layer of one part of the laminated film abuts the other part of the laminated film. In this case, since the protrusions derived from the inorganic fine particles present on the surface of the hard coat layer of one part of the laminated film easily damage the surface of the other part of the laminated film, the surface of the laminated film is easily damaged. In addition, a laminated film having a hard coat layer to which inorganic fine particles are added also has a drawback that glare or the like due to light reflection on the surface of the inorganic fine particles occurs. In the case where the laminated film surface is a thin film that requires transparency, if the laminated film surface is scratched, the transparency is lowered and the optical properties may be impaired.

  Therefore, a method of adding resin particles softer than inorganic fine particles as particles having a particle diameter of 1 μm or less as an antiblocking agent to the hard coat layer of a laminated film is known. As a method of adding the resin particles to the hard coat layer, resin particles are dispersed in an organic solvent to prepare a resin particle solvent dispersion, or the resin particle solvent dispersion is added to a solvent containing a binder resin, Alternatively, there is a method of adding a binder resin to the resin particle solvent dispersion.

  The resin particles having a particle diameter of 1 μm or less are likely to agglomerate because of their large specific surface area. Therefore, in the resin particle solvent dispersion, depending on the composition of the resin particles and the type of the organic solvent, the affinity between the resin particles and the organic solvent is low, and the resin particles may aggregate. When the resin particles are aggregated, the resin film has poor scratch resistance when the resin particle solvent dispersion is used as an antiblocking agent for the resin film. Further, when the resin particles are aggregated, workability is deteriorated and coating unevenness is likely to occur when applying a paint formed by blending the resin particle solvent dispersion.

  In the resin particle solvent dispersion, the resin particles may swell depending on the composition of the resin particles. Even when the resin particles swell, when the resin particle solvent dispersion is used as an antiblocking agent for the resin film, the scratch resistance of the resin film is deteriorated. In addition, when the resin particles swell, when applying a paint formed by blending the resin particle solvent dispersion, workability is deteriorated and uneven coating tends to occur.

  The present invention has been made in view of such circumstances, and the object thereof is to disperse well in an organic solvent without agglomeration or swelling, and to be used as an antiblocking agent for a resin film. The present invention provides a resin particle solvent dispersion capable of realizing a resin film having good scratch resistance and a coating material using the resin particle solvent dispersion.

  In the resin particle solvent dispersion containing the organic solvent and the crosslinked methacrylate ester resin particles dispersed in the organic solvent, the inventors of the present application have a structure derived from isobutyl methacrylate and / or tert-butyl methacrylate. Cross-linked methacrylic acid containing a unit and a structural unit derived from a polyfunctional vinyl monomer at a specific ratio, and having an average particle diameter in the range of 0.1 to 1.0 μm in the resin particle solvent dispersion Resin particle solvent dispersion in which acid ester resin particles are used and organic solvent having a solubility parameter within a specific range is used, and resin particles are well dispersed in organic solvent without agglomeration or swelling If the resin particle solvent dispersion is used as an anti-blocking agent for resin films, it is a resin with good scratch resistance. It found that can realize Irumu, and have completed the present invention.

  That is, the resin particle solvent dispersion of the present invention is a resin particle solvent dispersion containing an organic solvent and resin particles dispersed in the organic solvent, and the resin particles in the resin particle solvent dispersion. The average particle diameter is 0.1 to 1.0 μm, and the resin particles are structural units 60 to 85% by weight derived from isobutyl methacrylate and / or tert-butyl methacrylate, and polyfunctional vinyl. And 15 to 40% by weight of structural units derived from a monomer, and the solubility parameter of the organic solvent is in the range of 8.0 to 12.5.

  According to the said structure, resin particle contains 60 weight% or more of the structural unit derived from isobutyl methacrylate and / or tert-butyl methacrylate, and content of the structural unit derived from the polyfunctional vinyl-type monomer in a resin particle Is 40% by weight or less, the affinity between the resin particles and the organic solvent is increased, and the resin particles are well dispersed in the organic solvent without agglomeration. Moreover, according to the said structure, when the solubility parameter of the said organic solvent exists in the range of 8.0-12.5, the affinity of a resin particle and an organic solvent becomes high, and resin particles are in an organic solvent. Disperses well without agglomeration.

  Moreover, according to the said structure, the resin particle contains 15 weight% or more of the structural unit derived from a polyfunctional vinyl-type monomer, The structural unit derived from isobutyl methacrylate and / or tert-butyl methacrylate in a resin particle When the content is 85% by weight or less, the resin particles are well dispersed in the organic solvent without swelling in the organic solvent.

  As a result of these, when the resin particle solvent dispersion is used as an antiblocking agent for a resin film, the scratch resistance of the resin film is improved. Therefore, the resin particle solvent dispersion of the present invention is suitable as an antiblocking agent for resin films.

  The coating material of this invention is characterized by including the resin particle solvent dispersion of this invention, and binder resin.

  According to the said structure, since the said resin particle solvent dispersion is used, the coating material which can form a coating film with favorable scratch resistance is realizable.

  According to the present invention, a resin film having good scratch resistance can be realized when the resin particles are dispersed well in an organic solvent without being aggregated or swollen and used as an antiblocking agent for a resin film. A resin particle solvent dispersion and a paint using the same can be provided.

  The present invention is described in detail below.

[Resin particles]
First, the resin particles used in the resin particle solvent dispersion of the present invention will be described. The resin particles contain 60 to 85% by weight of structural units derived from isobutyl methacrylate and / or tert-butyl methacrylate and 15 to 40% by weight of structural units derived from a polyfunctional vinyl monomer. .

  The resin particles include a structural unit derived from a monofunctional vinyl monomer containing isobutyl methacrylate and / or tert-butyl methacrylate, and a structural unit derived from the polyfunctional vinyl monomer. . The monofunctional vinyl monomer is a compound having one ethylenically unsaturated group (broadly-defined vinyl group) per molecule.

  Ratio of the amount of structural units derived from isobutyl methacrylate and / or tert-butyl methacrylate relative to the whole of the resin particles (the resin particles are formed by participating in the polymerization reaction among the raw materials used for the production of the resin particles (Corresponding to the proportion of the amount of isobutyl methacrylate and / or tert-butyl methacrylate) to the amount of all components to be) is in the range of 60 to 85% by weight. Here, among the raw materials used for the production of the resin particles, the components involved in the polymerization reaction include a monofunctional vinyl monomer, a polyfunctional vinyl monomer, and a commonly used polymerization initiator. And an additive (reactive surfactant or the like) involved in the polymerization reaction used as necessary.

  When the proportion of the amount of structural units derived from isobutyl methacrylate and / or tert-butyl methacrylate is less than 60% by weight with respect to the entire resin particles, the resin particles aggregate in the resin particle solvent dispersion. As a result, a resin particle aggregate having a large particle diameter is generated, and the viscosity of the resin particle solvent dispersion is increased. As a result of the formation of a resin particle aggregate having a large particle size, when the resin particle solvent dispersion is used as an antiblocking agent for a resin film, the protrusions formed on the resin film surface due to the resin particles are high. Become. Therefore, when the resin films are wound in multiple rolls and the surfaces of the resin films are brought into contact with each other, the protrusions present on one surface easily damage the other surface, so the scratch resistance of the resin film is poor. Become. Further, as a result of the increase in the viscosity of the resin particle solvent dispersion, workability is deteriorated and coating unevenness is likely to occur when applying a paint formed by blending the resin particle solvent dispersion.

  On the other hand, when the proportion of the amount of the structural unit derived from isobutyl methacrylate and / or tert-butyl methacrylate exceeds 85% by weight with respect to the entire resin particles, a remarkable effect of improving the solvent dispersibility cannot be obtained. . In that case, the resin particles swell in the organic solvent in the resin particle solvent dispersion to increase the particle diameter of the resin particles, and the viscosity of the resin particle solvent dispersion increases. As a result of an increase in the particle diameter of the resin particles, when the resin particle solvent dispersion is used as an antiblocking agent for a resin film, protrusions formed on the resin film surface due to the resin particles become high. Therefore, when the resin films are wound in multiple rolls and the surfaces of the resin films are brought into contact with each other, the protrusions present on one surface easily damage the other surface, so the scratch resistance of the resin film is poor. Become. Further, as a result of the increase in the viscosity of the resin particle solvent dispersion, workability is deteriorated and coating unevenness is likely to occur when applying a paint formed by blending the resin particle solvent dispersion.

  The ratio of the amount of structural units derived from isobutyl methacrylate and / or tert-butyl methacrylate to the entire resin particles is more preferably 65 to 80% by weight. Thereby, aggregation and swelling of the resin particles in the particle solvent dispersion can be further suppressed.

  The polyfunctional vinyl monomer is a compound having a plurality of ethylenically unsaturated groups (broadly defined vinyl groups) in one molecule. Examples of the polyfunctional vinyl monomer include styrene polyfunctional vinyl monomers such as divinylbenzene; alkylene glycol di (meth) acrylate (for example, ethylene glycol di (meth) acrylate), trimethylolpropane tri ( And (meth) acrylic acid ester-based polyfunctional vinyl monomers such as (meth) acrylate. The polyfunctional vinyl monomer is preferably at least one monomer of divinylbenzene, alkylene glycol di (meth) acrylate, and trimethylolpropane tri (meth) acrylate. Thereby, aggregation of the resin particles in the resin particle solvent dispersion can be further suppressed, and the strength, heat resistance, and solvent resistance of the resin particles can be improved. The alkylene group of the alkylene glycol di (meth) acrylate is preferably an alkylene group having 2 to 4 carbon atoms. In the present specification, “(meth) acrylate” means acrylate or methacrylate.

  Ratio of the amount of structural units derived from the polyfunctional vinyl-based monomer to the entire resin particles (all the raw materials used for the production of the resin particles are involved in the polymerization reaction to form the resin particles (Corresponding to the ratio of the amount of the polyfunctional vinyl monomer to the amount of the component) is in the range of 15 to 40% by weight.

  When the ratio of the amount of the structural unit derived from the polyfunctional vinyl monomer to the whole resin particles is less than 15% by weight, the resin particles swell in the organic solvent in the resin particle solvent dispersion. As the particle diameter of the resin particles increases, the viscosity of the resin particle solvent dispersion increases. As a result of an increase in the particle diameter of the resin particles, when the resin particle solvent dispersion is used as an antiblocking agent for a resin film, protrusions formed on the resin film surface due to the resin particles become high. Therefore, when the resin films are wound in multiple rolls and the surfaces of the resin films are brought into contact with each other, the protrusions present on one surface easily damage the other surface, so the scratch resistance of the resin film is poor. Become. Further, as a result of the increase in the viscosity of the resin particle solvent dispersion, workability is deteriorated and coating unevenness is likely to occur when applying a paint formed by blending the resin particle solvent dispersion.

  On the other hand, when the ratio of the amount of the structural unit derived from the polyfunctional vinyl monomer to the entire resin particles exceeds 40% by weight, the aggregation and swelling of the resin particles in the resin particle solvent dispersion is remarkable. The suppression effect cannot be obtained. In that case, the amount of structural units derived from isobutyl methacrylate and / or tert-butyl methacrylate is less than the required amount, and the affinity with the solvent deteriorates. Therefore, the resin particles aggregate in the resin particle solvent dispersion to form a resin particle aggregate having a large particle size, and the viscosity of the resin particle solvent dispersion is increased. As a result of the formation of a resin particle aggregate having a large particle size, when the resin particle solvent dispersion is used as an antiblocking agent for a resin film, the protrusions formed on the resin film surface due to the resin particles are high. Become. Therefore, when the resin films are wound in multiple rolls and the surfaces of the resin films are brought into contact with each other, the protrusions present on one surface easily damage the other surface, so the scratch resistance of the resin film is poor. Become. Further, as a result of the increase in the viscosity of the resin particle solvent dispersion, workability is deteriorated and coating unevenness is likely to occur when applying a paint formed by blending the resin particle solvent dispersion.

  The ratio of the amount of structural units derived from the polyfunctional vinyl monomer to the entire resin particles is more preferably 15 to 30% by weight. Thereby, aggregation of the resin particle at the time of superposition | polymerization can further be suppressed.

  In addition to the structural unit derived from isobutyl methacrylate and / or tert-butyl methacrylate as the structural unit derived from the monofunctional vinyl-based monomer, the resin particles are other than isobutyl methacrylate and tert-butyl methacrylate. A structural unit derived from another monofunctional vinyl monomer may be included.

  Examples of the other monofunctional vinyl monomers include, for example, aromatic vinyl monomers; (meth) acrylic acid ester monomers other than isobutyl methacrylate and tert-butyl methacrylate, vinyl halide monomers, A vinyl cyanide monomer can be used. Examples of the aromatic vinyl monomer that can be used include styrenes (styrene monomers) such as styrene and α-methylstyrene. Examples of (meth) acrylic acid ester monomers other than the isobutyl methacrylate and tert-butyl methacrylate include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, ( Alkyl (meth) acrylates such as n-butyl methacrylate, isobutyl acrylate, tert-butyl acrylate, n-pentyl (meth) acrylate, and n-hexyl (meth) acrylate can be used. These other monofunctional vinyl monomers may be used alone or in combination of two or more. Among these other monofunctional vinyl monomers, at least one monomer selected from styrenes and alkyl (meth) acrylates (excluding isobutyl methacrylate and tert-butyl methacrylate) is preferable, and styrene and At least one monomer selected from alkyl (meth) acrylates (excluding isobutyl methacrylate and tert-butyl methacrylate) in which the alkyl group has 1 to 4 carbon atoms is more preferred. Thereby, the resin particle which has a favorable total light transmittance is realizable. When the monofunctional vinyl monomer is an alkyl (meth) acrylate having an alkyl group having 5 or more carbon atoms, the resin particles are easily fused, and the resin particles become primary particles in the resin particle solvent dispersion. Since it becomes difficult to become, it is not preferable. In the present specification, “(meth) acryl” means acryl or methacryl, “(meth) acrylate” means acrylate or methacrylate, and “(meth) acryloyl” means acryloyl or methacryloyl. To do.

  The monofunctional vinyl monomer is included in the second vinyl monomer when the homopolymer has a glass transition temperature (however, when the resin particles are produced by a seed polymerization method described later). The glass transition temperature of the homopolymer of the monofunctional vinyl monomer is preferably in the range of −60 to 110 ° C., more preferably in the range of 30 to 110 ° C., and 40 to 110 More preferably, it is within the range of ° C. When the glass transition temperature of the homopolymer of the monofunctional vinyl monomer is less than −60 ° C., the resin particle solvent dispersion tends to swell in the resin particle solvent dispersion, and the resin particle solvent dispersion There is a possibility that the scratch resistance of the hard coat layer formed by using this will deteriorate. When the glass transition temperature of the homopolymer of the monofunctional vinyl monomer exceeds 110 ° C., the resin particles become hard, so that the hard coat layer formed using the resin particle solvent dispersion has scratch resistance. There is a risk of getting worse.

[Production method of resin particles]
The polymerization method for obtaining the resin particles is not particularly limited, but seed polymerization method, emulsion polymerization method, soap-free emulsion polymerization method (emulsion polymerization method not using a surfactant), suspension polymerization method, dispersion polymerization method, etc. This method can be used. Among these polymerization methods, a method other than the suspension polymerization method in which the particle size distribution is generally wide is preferable, and an average particle size of 0.1 to 1.0 μm having a preferable particle size distribution (a variation coefficient of the particle size is 20% or less). Since the resin particles can be easily obtained, a seed polymerization method, an emulsion polymerization method, or a soap-free emulsion polymerization method is more preferable.

[Method of producing resin particles by seed polymerization method]
In the method for producing resin particles by the seed polymerization method, the second vinyl monomer is absorbed into the seed particles made of the polymer of the first vinyl monomer, and the second vinyl monomer is polymerized. Is the method.

  The seed particles preferably have a weight average molecular weight (Mw) of 50000 or less. When the weight average molecular weight of the seed particles exceeds 50,000, the seed particles hardly absorb the second vinyl monomer, and the particle size distribution of the obtained resin particles is widened. When the particle size distribution of the resin particles is widened, the resin particles are difficult to disperse into primary particles or a state close thereto.

  The seed particles are preferably non-crosslinked particles or finely crosslinked particles (particles crosslinked to such an extent that they can be dissolved in a solvent). When the seed particles are cross-linked so as not to dissolve in the solvent, the amount of the second vinyl monomer absorbed by the seed particles is reduced, and furthermore, the resin particles become a core-shell shape (the seed particles keep a spherical shape). ), The resin particles are deformed, etc., which is not preferable in order to obtain spherical resin particles having a uniform particle interior.

  The ratio of the seed particles to the total weight of the raw materials constituting the resin particles, that is, the ratio of the seed particles to the total weight of the resin particles is preferably 10% by weight or less. When the seed particles are non-crosslinked or microcrosslinked, when the ratio of the seed particles to the total weight of the resin particles exceeds 10% by weight, the seed particles having a low glass transition temperature are melted when the resin particles are dried, and the resin particles Since it becomes a factor which fuses each other, it is not preferable. The ratio of the seed particles to the total weight of the resin particles can be analyzed by dissolving the seed particles in the resin particles with a solvent.

  The first vinyl monomer and the second vinyl monomer, which are combined together, form the resin particles by participating in a polymerization reaction among the raw materials used in the production of the resin particles. Of the monofunctional vinyl monomer containing 60 to 85% by weight of isobutyl methacrylate and / or tert-butyl methacrylate and the raw materials used for the production of the resin particles. Any composition may be used as long as it is a polymerizable monomer mixture containing 15 to 40% by weight of a polyfunctional vinyl monomer with respect to the amount of all the components involved in the reaction to form the resin particles. . As described above, since the seed particles are preferably non-crosslinked particles or finely crosslinked particles, the first vinyl monomer does not contain a polyfunctional vinyl monomer or the first vinyl monomer. The second vinyl monomer comprises a monofunctional vinyl monomer and a polyfunctional vinyl monomer, while containing a small amount of a polyfunctional vinyl monomer to the extent that finely crosslinked particles can be obtained by polymerization of the monomer. It is preferable that the content of the polyfunctional vinyl monomer is higher than that of the first vinyl monomer.

  The first vinyl monomer is preferably the (meth) acrylic acid ester monomer or the aromatic vinyl monomer, more preferably the alkyl (meth) acrylate or styrene, More preferably, it is an alkyl (meth) acrylate having 1 to 4 carbon atoms.

  The polymerization of the second vinyl monomer is usually performed in a state where seed particles that have absorbed the second vinyl monomer are dispersed in an aqueous medium. The aqueous medium is not particularly limited, and examples thereof include water and a mixed medium of water and a water-soluble organic medium (lower alcohol (alcohol having 5 or less carbon atoms) such as methanol and ethanol). The amount of the aqueous medium used is usually in the range of 100 to 1000 parts by weight with respect to 100 parts by weight of the second vinyl monomer in order to stabilize the resin particles.

  The polymerization of the second vinyl monomer in the aqueous medium is preferably performed by stirring an aqueous suspension in which the second vinyl monomer is dispersed as spherical droplets. The stirring may be performed loosely enough to prevent, for example, floating of spherical droplets and sedimentation of particles after polymerization.

  The polymerization temperature of the second vinyl monomer is preferably in the range of 30 to 100 ° C, and more preferably in the range of 40 to 80 ° C. The time for maintaining this polymerization temperature is preferably within the range of 0.1 to 20 hours.

  In the polymerization of the second vinyl monomer, a polymerization initiator is usually used. Examples of the polymerization initiator include organic peroxides such as benzoyl peroxide, lauroyl peroxide, tert-butyl peroxyisobutyrate, acetyl peroxide, methyl ethyl ketone peroxide, tert-butyl peroxide, and dicumyl peroxide; Azo compounds such as 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (2-methylpropionate), etc. It is done. These polymerization initiators may be used alone or in combination of two or more.

  In the polymerization of the second vinyl monomer, when the surfactant concentration is not less than the critical micelle concentration, the polymerization initiator may be benzoyl peroxide, 2,2′-azobisisobutyronitrile, or the like. It is preferable to use an oil-soluble polymerization initiator. In the polymerization of the second vinyl monomer, when the oil-soluble polymerization initiator is used, the target particle size (0.1%) is compared with the case where a water-soluble polymerization initiator such as potassium persulfate is used. It is possible to suppress the generation of fine resin particles smaller than the resin particles (˜1.0 μm).

  The amount of the polymerization initiator used is preferably in the range of 0.01 to 10 parts by weight and in the range of 0.01 to 5 parts by weight with respect to 100 parts by weight of the second vinyl monomer. It is more preferable that When the usage-amount of the said polymerization initiator is less than 0.01 weight part with respect to 100 weight part of 2nd vinylic monomers, it is difficult for a polymerization initiator to fulfill | perform a polymerization start function. Moreover, when the usage-amount of the said polymerization initiator exceeds 10 weight part with respect to 100 weight part of 2nd vinylic monomers, since it is uneconomical in cost, it is not preferable.

  A surfactant is preferably used for the polymerization of the second vinyl monomer. The surfactant is not particularly limited, and any of an anionic surfactant, a nonionic surfactant, a cationic surfactant, and a zwitterionic surfactant can be used.

  Examples of the anionic surfactant include dialkyl sulfosuccinates such as sodium dioctyl sulfosuccinate; phosphate esters such as sodium polyoxyethylene alkylphenyl ether phosphate and sodium polyoxyalkylene aryl ether phosphate; sodium oleate Fatty acid soap such as castor oil potash soap; alkyl sulfate such as sodium lauryl sulfate and ammonium lauryl sulfate; alkyl benzene sulfonate such as sodium dodecylbenzene sulfonate; alkyl naphthalene sulfonate; alkane sulfonate; alkyl phosphate ester salt Naphthalenesulfonic acid formalin condensate; polyoxyethylene alkylphenyl ether sulfate ester salt; polyoxyethylene alkyl sulfate ester salt and the like.

  Examples of the nonionic surfactant include polyoxyethylene alkyl ethers such as polyoxyethylene tridecyl ether, polyoxyethylene alkyl phenyl ethers, polyoxyethylene styrenated phenyl ethers, and alkylene groups having 3 or more carbon atoms. Polyoxyalkylene alkyl ethers such as polyoxyalkylene tridecyl ether, polyoxyethylene fatty acid esters, sorbitan fatty acid esters such as sorbitan monostearate and sorbitan monopalmitate, polyoxyethylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monolaurate, Polyoxyethylene alkylamine, glycerin fatty acid ester, oxyethylene-oxypropylene block copolymer, sucrose fatty acid ester (eg , Trade name of Mitsubishi Chemical Foods Co., Ltd. "Ryoto (registered trademark) sugar ester"), and the like.

  Examples of the cationic surfactant include alkylamine salts such as laurylamine acetate and stearylamine acetate, and quaternary ammonium salts such as lauryltrimethylammonium chloride.

  Examples of the zwitterionic surfactant include lauryl dimethylamine oxide and phosphate ester or phosphite ester surfactants.

  Of these surfactants, at least one of an anionic surfactant and a nonionic surfactant is preferably used as the surfactant. Further, phosphate ester salts and sulfosuccinates are preferable as the anionic surfactant, and polyoxyethylene alkyl phenyl ether and polyoxyethylene styrenated phenyl ether are preferable as the nonionic surfactant. Moreover, the said surfactant may be used independently and may be used in combination of 2 or more type.

  The amount of the surfactant used in the polymerization of the second vinyl monomer ranges from 1 to 5% by weight with respect to the total amount of the first vinyl monomer and the second vinyl monomer. It is preferable to be within. When the amount of the surfactant used is less than 1% by weight based on the total amount of the first vinyl monomer and the second vinyl monomer, it is difficult to maintain the polymerization stability. Therefore, it is not preferable. Moreover, when the usage-amount of surfactant exceeds 5 weight% with respect to the total amount of a 1st vinylic monomer and a 2nd vinylic monomer, it is intended particle diameter (0.1-0.1). This is not preferable because fine resin particles smaller than 1.0 μm) resin particles are generated and the unblocking performance of the resin particles may be deteriorated.

  A chain transfer agent may be added to the second vinyl monomer polymerization 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, tert-octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, n-hexyl mercaptan; terpenes such as γ-terpinene and dipentene; chloroform, Halogenated hydrocarbons such as carbon tetrachloride, dichloromethane and dibromomethane; α-methylstyrene dimer; phenolic compounds such as 2,6-di-tert-butyl-4-methylphenol and styrenated phenol; allyl such as allyl alcohol Compounds and the like. Further, an additive such as an antioxidant may be added to the second vinyl monomer polymerization system in order to improve the heat resistance of the resin particles.

  The seed particles are obtained by polymerizing the first vinyl monomer. The polymerization method of the first vinyl monomer is not particularly limited, and a soap-free emulsion polymerization method, an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, a seed polymerization method, and the like can be used. Among these polymerization methods, a soap-free emulsion polymerization method or an emulsion polymerization method using a reactive surfactant (a surfactant having an ethylenically unsaturated group) is preferable.

  The polymerization temperature of the first vinyl monomer is preferably in the range of 30 to 100 ° C, and more preferably in the range of 40 to 80 ° C. The time for maintaining this temperature is preferably in the range of 1 to 30 hours.

  In the polymerization of the first vinyl monomer, a polymerization initiator is usually used. As the polymerization initiator used for the polymerization of the first vinyl monomer, the same polymerization initiator as that used for the second vinyl monomer can be used, but potassium persulfate, ammonium persulfate, etc. The water-soluble polymerization initiator is preferably used.

  The polymerization initiator is preferably used in an amount of 0.01 to 10 parts by weight, based on 100 parts by weight of the first vinyl monomer. More preferably within the range. When the usage-amount of the said polymerization initiator is less than 0.01 weight part with respect to 100 weight part of 1st vinylic monomers, the said polymerization initiator is hard to fulfill | perform a polymerization start function. Moreover, when the usage-amount of the said polymerization initiator exceeds 10 weight part with respect to 100 weight part of 1st vinylic monomers, since it is uneconomical in cost, it is not preferable.

  In the case of producing seed particles by polymerizing the first vinyl monomer by the emulsion polymerization method, the surfactant used for the polymerization of the first vinyl monomer is the second vinyl monomer. Various surfactants listed as those that can be used for polymerization may be used, and anionic surfactants having an ethylenically unsaturated group (hereinafter referred to as “reactive anionic surfactants”) are used. May be. Since the specific example and preferable usage amount of the reactive anionic surfactant are the same as the method for producing resin particles by the emulsion polymerization method described later, the description thereof is omitted here.

  A chain transfer agent can be added to the polymerization of the first vinyl monomer in order to adjust the molecular weight. As the chain transfer agent, those used for the polymerization of the second vinyl monomer can be used.

[Method of producing resin particles by emulsion polymerization method]
The method for producing resin particles by the emulsion polymerization method is based on 60 to 85% by weight of methacrylic acid based on the amount of all the components involved in the polymerization reaction among the raw materials used for the production of the resin particles. Among the monofunctional vinyl-based monomer containing isobutyl acrylate and / or tert-butyl methacrylate and the raw materials used for the production of the resin particles, the amount of all components involved in the polymerization reaction to form the resin particles A method of emulsifying a polymerizable monomer mixture containing 15 to 40% by weight of a polyfunctional vinyl monomer in a medium in the presence of a surfactant and polymerizing in the presence of a polymerization initiator It is.

  Examples of the polymerization initiator include organic peroxides such as benzoyl peroxide, lauroyl peroxide, acetyl peroxide, methyl ethyl ketone peroxide, tert-butyl peroxide, and dicumyl peroxide; 2,2′-azobisisobutyl Ronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis [2- (2-imidazolin-2-yl) propane] dihydrochloride, 2,2′-azobis [ 2- (2-Imidazolin-2-yl) propane] disulfate dihydrate, 2,2′-azobis (2-amidinopropane) dihydrochloride, 2,2′-azobis [N- (2-carboxy) Ethyl) -2-methylpropionamidine] hydrate, 2,2′-azobis {2- [1- (2-hydroxyethyl) -2-imidazolin-2-yl] propyl Pan} dihydrochloride, 2,2′-azobis [2- (2-imidazolin-2-yl) propane], 2,2′-azobis (1-imino-1-pyrrolidino-2-methylpropane) dihydrochloride 2,2′-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2′-azobis [2-methyl-N- (2- Hydroxyethyl) propionamide], azo compounds such as 4,4-azobis (4-cyanopentanoic acid); and persulfates such as potassium persulfate, ammonium persulfate, and sodium persulfate. These polymerization initiators may be used alone or in combination of two or more. Moreover, you may use what combined the said persulfate or organic peroxide, and a reducing agent as a polymerization initiator. Such a combination of polymerization initiators is called a redox polymerization initiator. Examples of the reducing agent include sodium sulfoxylate formaldehyde, sodium bisulfite, ammonium bisulfite, sodium thiosulfate, ammonium thiosulfate, hydrogen peroxide, sodium hydroxymethanesulfinate, L-ascorbic acid or a salt thereof, cuprous copper Examples thereof include salts and ferrous salts. These reducing agents may be used alone or in combination of two or more.

  The polymerization initiator varies depending on the type thereof, but it is preferably used within a range of 0.1 to 5 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture, and 0.3 to 3 parts by weight. More preferably, it is used within the range of parts.

  Further, a chain transfer agent may be added to the polymerization system in the emulsion polymerization method. As said chain transfer agent, the various chain transfer agents mentioned as what is used for superposition | polymerization of the 2nd vinyl-type monomer in the said seed polymerization method can be used. The chain transfer agent is preferably used within a range of 0.1 to 5 parts by weight, and is used within a range of 0.3 to 3 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture. It is more preferable.

  As a medium used for the emulsion polymerization method, it is preferable to use an aqueous medium. As the aqueous medium, water alone or a mixture of water and lower alcohol (methanol, ethanol, isopropyl alcohol, etc.) can be used, but water alone is preferable from the viewpoint of waste liquid treatment.

  The amount of the aqueous medium used is preferably in the range of 200 to 2000 parts by weight and more preferably in the range of 300 to 1500 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture. . When the amount of the aqueous medium used is less than 200 parts by weight, the stability of the particles during the polymerization is deteriorated, and an aggregate of resin particles may be formed after the polymerization, which is not preferable. When the amount of the aqueous medium used is more than 2000 parts by weight, productivity may be deteriorated, which is not preferable.

  The stirring rotation speed of the polymerization system is preferably 100 to 500 rpm, for example, when a reaction vessel having an internal volume of 5 L is used. Moreover, although superposition | polymerization temperature changes with kinds of monomer to be used and the kind of polymerization initiator, it is preferable to exist in the range of 30-100 degreeC. The polymerization time is preferably 2 to 10 hours.

  As the surfactant, various surfactants listed as those that can be used for polymerization of the second vinyl monomer in the seed polymerization method can be used. It is preferable to use a reactive anionic surfactant (anionic surfactant having an ethylenically unsaturated group), more preferably a reactive anionic surfactant having a polyoxyalkylene moiety. More preferably. Examples of the ethylenically unsaturated group include a vinyl group and a (meth) acryloyl group.

  In the reactive anionic surfactant, the ethylenically unsaturated group is copolymerized with the polymerizable monomer mixture and is taken into the resin particles to be formed, so that the medium in which the resin particles are dispersed (for example, aqueous) It does not remain in the medium). On the other hand, when a general anionic surfactant having no ethylenically unsaturated group is used, the anionic surfactant remains in the medium (for example, an aqueous medium) after the polymerization reaction. There is a possibility that the resulting dispersion of resin particles foams and causes a decrease in handleability.

  In addition, the reactive anionic surfactant having a polyoxyalkylene moiety has a polyoxyalkylene moiety in addition to an ethylenically unsaturated group, and therefore, aggregation and precipitation of resin particles are difficult to occur. Therefore, by using a reactive anionic surfactant having a polyoxyalkylene moiety, this polyoxyalkylene moiety can provide a repulsive action between resin particles after polymerization, thereby suppressing foaming after polymerization. it can.

  The reactive anionic surfactant has sulfonate, sulfate, phosphate, phosphate ester, sulfosuccinate, carboxylate, acylamino acid salt and the like as an anionic site. This anionic site becomes a functional group on the surface of the obtained resin particle. Here, examples of these salts include ammonium salts, sodium salts, potassium salts, and the like.

  Specific examples of the reactive anionic surfactant having a polyoxyalkylene moiety include, for example, polyoxyethylene-1- (allyloxymethyl) alkyl ether sulfate ammonium salt manufactured by Daiichi Kogyo Seiyaku Co., Ltd. AQUALON (registered trademark) KH-10 "(trade name, polyoxyethylene chain length 10) and" AQUALON (registered trademark) KH-1025 "(trade name," AQUALON (registered trademark) KH-10 "25% by weight aqueous solution ); "Aqualon (registered trademark) HS-10" (trade name, polyoxyethylene chain length 10), which is a polyoxyethylene alkylpropenyl phenyl ether sulfate ammonium salt manufactured by Daiichi Kogyo Seiyaku Co., Ltd., "Aqualon (registered trademark) ) HS-20 "(trade name, polyoxyethylene chain length 20)," AQUALON ( Registered trademark) BC-10 "(trade name, polyoxyethylene chain length 10) and" AQUALON (registered trademark) BC-20 "(trade name, polyoxyethylene chain length 20); polyoxyalkylene manufactured by Kao Corporation “Latemul (registered trademark) PD-104” (trade name), which is ammonium alkenyl ether sulfate; α-sulfo-ω- (1-alkoxymethyl-2- (2-propenyloxy) ethoxy) -poly (manufactured by ADEKA Corporation) Oxy-1,2-ethanediyl) ammonium salt “ADEKA rear soap (registered trademark) SR-10” (trade name, polyoxyethylene chain length 10) and “ADEKA rear soap (registered trademark) SR— 20) (trade name, polyoxyethylene chain length 20); polyoxypropylene allyl ether phosphate S manufactured by ADEKA Corporation “Adekalia Soap (registered trademark) PP-70” (trade name); “Antox MS-60” (trade name), a bis (polyoxyethylene phenyl ether) methacrylate sulfate ester salt manufactured by Nippon Emulsifier Co., Ltd. However, it is not limited to these. These anionic surfactants may be used alone or in combination of two or more.

  Examples of the reactive anionic surfactant other than the reactive anionic surfactant having a polyoxyalkylene moiety include sodium p-styrene sulfonate and sodium allyl alkyl sulfonate.

  The amount of the surfactant used is preferably in the range of 0.01 to 5 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture.

  Further, in order to stabilize the dispersion of the polymerizable monomer mixture in the medium, a polymerization dispersant made of a polymer may be added to the polymerization system in the emulsion polymerization method. Examples of the polymerization dispersant made of the polymer include polyvinyl alcohol, methyl cellulose, ethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, carboxyethyl cellulose, and amino-modified silicone. These polymerization dispersants may be used alone or in combination of two or more. The polymerization dispersant is preferably used in an amount of 0.01 to 5 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture.

[Method of producing resin particles by soap-free emulsion polymerization method]
The method for producing resin particles by a soap-free emulsion polymerization method is the same as the method for producing resin particles by an emulsion polymerization method, except that the polymerizable monomer mixture is emulsified in a medium in the absence of a surfactant. .

[Post-treatment of polymerization]
In the above-described polymerization such as seed polymerization, emulsion polymerization, soap-free emulsion polymerization, a slurry containing resin particles is obtained. As a method for isolating the resin particles from the slurry, a known method can be used. For example, a spray drying method, a method of drying by attaching to a heated rotating drum typified by a drum dryer, or freeze drying The law etc. can be used. Of these methods, the spray drying method is preferred.

  The spray drying method is generally a method of drying resin particles by spraying a water dispersion (slurry containing resin particles) together with a gas stream using a spray dryer such as a spray dryer or an air dryer. .

  The temperature (supply temperature) at the slurry inlet of the spray dryer (inlet where the slurry is sprayed and introduced) is preferably in the range of 80 ° C to 220 ° C. When the temperature at the slurry inlet is higher than 220 ° C., the resin particles are likely to be fused with each other, and a resin particle aggregate in which the resin particles are connected to each other may be obtained. When the temperature at the slurry inlet is less than 80 ° C., drying may be insufficient or drying efficiency may be lowered.

  Moreover, it is preferable that the temperature (exhaust temperature) of the powder outlet (exhaust temperature from which the resin particles are discharged) of the spray dryer is within a range of 40 ° C to 100 ° C. Moreover, when the temperature at the powder outlet is lower than 40 ° C., drying may be insufficient. On the other hand, when the temperature at the powder outlet is higher than 100 ° C., the resin particles may be easily fused.

  The resin particles may be classified after polymerization, and the classified resin particles may be spray-dried. Thereby, the coarse particle contained in the resin particle solvent dispersion can be reduced. As a result, when the hard coat paint formed by blending the resin particle solvent dispersion is applied on the base film to form the hard coat layer, streaks are generated in the hard coat layer, or the hard coat layer and the base material are formed. It is possible to prevent bright spots from being generated in a laminated film constituted by films. In addition, the resin particles dried by a spray drying method or the like may be subjected to a treatment for breaking up the aggregates using a pulverizer, a pulverizer, or the like.

[Resin particle solvent dispersion]
The resin particle solvent dispersion of the present invention is a resin particle solvent dispersion containing an organic solvent and the resin particles dispersed in the organic solvent, wherein the resin particles in the resin particle solvent dispersion The average particle diameter is in the range of 0.1 to 1.0 μm, and the solubility parameter (hereinafter referred to as “SP value”) of the organic solvent is in the range of 8.0 to 12.5.

  The average particle diameter of the resin particles in the resin particle solvent dispersion is in the range of 0.1 to 1.0 μm, but is preferably in the range of 0.2 to 0.9 μm. When the average particle diameter of the resin particles in the resin particle solvent dispersion is less than 0.1 μm, the antiblocking performance of the resin particles is deteriorated. When the average particle diameter of the resin particles in the resin particle solvent dispersion exceeds 1.0 μm, a hard coat layer is formed by coating a hard coat paint containing the resin particle solvent dispersion on the substrate. When the is formed, the protrusion formed on the surface of the hard coat layer due to the resin particles becomes high. Therefore, when the laminated film is wound in multiple rolls and the hard coat layer of a part of the laminated film comes into contact with the laminated film of the other part, the protrusions present on the surface of the hard coat layer of the part of the laminated film However, since the surface of the laminated film of other parts is easily damaged, the scratch resistance of the hard coat layer is deteriorated.

  The coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is preferably 20% or less. Thereby, in the resin particle solvent dispersion, the resin particles are easily dispersed into primary particles or a state close thereto. The scratch resistance of the hard coat layer formed with the hard coat layer can be further improved by coating a hard coat paint formed by using the resin particle solvent dispersion on the substrate.

  The organic solvent is an organic solvent having an SP value in the range of 8.0 to 12.5, but is preferably an organic solvent having an SP value in the range of 8.0 to 10.0. When the SP value of the organic solvent is out of the above range, the resin particles aggregate in the resin particle solvent dispersion to form a resin particle aggregate having a large particle diameter, and the viscosity of the resin particle solvent dispersion is high. Become. As a result of the formation of a resin particle aggregate having a large particle size, when the resin particle solvent dispersion is used as an antiblocking agent for a resin film, the protrusions formed on the resin film surface due to the resin particles are high. Become. Therefore, when the resin films are wound in multiple rolls and the surfaces of the resin films are brought into contact with each other, the protrusions present on one surface easily damage the other surface, so the scratch resistance of the resin film is poor. Become. Further, as a result of the increase in the viscosity of the resin particle solvent dispersion, workability is deteriorated and coating unevenness is likely to occur when applying a paint formed by blending the resin particle solvent dispersion.

  Examples of the organic solvent having an SP value in the range of 8.0 to 12.5 include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ethyl acetate, propyl acetate, butyl acetate, ethyl lactate, Esters such as butyl lactate, 3-methyl-3-methoxybutanol, 3-methyl-3-methoxybutyl acetate, ethyl-3-ethoxypropionate; alcohols such as isopropyl alcohol; ethylene glycol monomethyl ether, ethylene glycol mono Ethyl ether, ethylene glycol monopropyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, propylene glycol monomethyl ether, Propylene glycol monoethyl ether, propylene glycol monopropyl ether, and acetate thereof each ether: toluene, toluene such as xylene; dimethylformamide; tetrahydrofuran. These organic solvents may be used alone or in combination of two or more. The solid content concentration of the resin particle solvent dispersion is not particularly limited.

  The organic solvent is preferably an organic solvent having a boiling point in the range of 50 to 150 ° C. If the boiling point of the organic solvent is in the range of 50 to 150 ° C., the drying speed of the organic solvent after application of the paint containing the resin particle solvent dispersion is appropriate, and the organic solvent is uniformly evaporated and dried. Aggregation between particles is difficult to occur and uneven coating is difficult to occur. If the boiling point of the organic solvent is less than 50 ° C., the drying speed is high at the time of drying after coating of the paint containing the resin particle solvent dispersion, and the resin particles are likely to aggregate to cause uneven coating. On the other hand, if the boiling point of the organic solvent is higher than 150 ° C., the drying speed after coating of the paint containing the resin particle solvent dispersion is slowed, and the productivity is lowered.

  The resin particle solvent dispersion has an apparent viscosity of 100 mPa · s or less when the amount of the organic solvent is adjusted so that the solid content concentration is 20% by weight, but the apparent viscosity is 50 mPa · s or less. More preferably, the apparent viscosity is more preferably 20 mPa · s or less. When the apparent viscosity exceeds 100 mPa · s, uneven coating is likely to occur when a hard coat paint formed by blending the resin particle solvent dispersion is applied, and the transparency of the hard coat layer is lowered.

  The resin particle solvent dispersion of the present invention can be suitably used as an antiblocking agent for resin films such as light diffusing films and antiglare films used in flat panel displays and the like, and in particular, coated on one or both surfaces of a resin film. It can be suitably used as a resin particle solvent dispersion added to a paint for forming a film (particularly a hard coat layer).

〔paint〕
The paint of the present invention contains the resin particle solvent dispersion of the present invention and a binder resin. The coating material of the present invention is preferably a coating solution for a hard coat layer. The coating liquid for the hard coat layer contains the resin particle solvent dispersion of the present invention and a binder resin.

  Examples of the binder resin include a thermoplastic resin, a thermosetting resin, a mixture of an ionizing radiation curable resin and an ionizing radiation polymerization initiator.

  Examples of the thermoplastic resin include cellulose derivatives such as acetylcellulose, nitrocellulose, acetylbutylcellulose, ethylcellulose, and methylcellulose; vinyl acetate homopolymers or copolymers, vinyl chloride homopolymers or copolymers, and chlorides. Vinylidene homopolymers or copolymers; acetal resins such as polyvinyl formal and polyvinyl butyral; acrylic resins (polyacrylate esters) and their copolymer resins, methacrylic resins (polymethacrylate esters) and their copolymer resins, etc. (Meth) acrylic resin; polystyrene resin; polyamide resin; linear polyester resin; polycarbonate resin.

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

  The ionizing radiation curable resin may be any resin that can be cured by irradiating with ionizing radiation (ultraviolet rays, electron beams, etc.), such as an ionizing radiation polymerizable monomer or an ionizing radiation polymerizable prepolymer (ionizing radiation). What mixed 1 type (s) or 2 types or more, such as a polymerizable oligomer), can be used. As the ionizing radiation polymerizable monomer or ionizing radiation polymerizable prepolymer, an ionizing radiation polymerizable polyfunctional monomer having two or more ionizing radiation polymerizable functional groups in one molecule, or in one molecule An ionizing radiation polymerizable polyfunctional prepolymer having two or more ionizing radiation polymerizable functional groups is preferred.

  The ionizing radiation polymerizable functional group possessed by the ionizing radiation polymerizable polyfunctional prepolymer or the polyfunctional monomer is a photopolymerizable functional group, an electron beam polymerizable functional group, or a radiation polymerizable functional group. Are preferred, and photopolymerizable functional groups are particularly preferred. Specific examples of the photopolymerizable functional group include unsaturated polymerizable functional groups such as a (meth) acryloyl group, a vinyl group, a styryl group, and an allyl group. ) An acryloyl group is preferred.

  The ionizing radiation polymerizable polyfunctional prepolymer is preferably a polyfunctional prepolymer having two or more photopolymerizable functional groups (hereinafter referred to as “photopolymerizable polyfunctional prepolymer”). As the photopolymerizable polyfunctional prepolymer, a (meth) acrylic prepolymer having two or more (meth) acryloyl groups in one molecule is particularly preferably used. Such a (meth) acrylic prepolymer becomes a three-dimensional network structure by crosslinking and curing. Examples of the (meth) acrylic prepolymer include urethane (meth) acrylate, polyester (meth) acrylate, epoxy (meth) acrylate, and melamine (meth) acrylate.

  As the ionizing radiation polymerizable polyfunctional monomer, the above-mentioned polyfunctional vinyl monomers can be used, but a polyfunctional monomer having two or more photopolymerizable functional groups (hereinafter referred to as “photopolymerization”). Preferred polyfunctional monomer ”). Specific examples of the photopolymerizable polyfunctional monomer include alkylene glycol di (meth) acrylates such as neopentyl glycol acrylate, 1,6-hexanediol (meth) acrylate, propylene glycol di (meth) acrylate; Polyoxyalkylene glycol di (meth) acrylates such as ethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate; pentaerythritol di (meta) ) Di (meth) acrylates of trihydric or higher polyhydric alcohols such as acrylate; 2,2-bis [4- (acryloxy-diethoxy) phenyl] propane, 2,2-bis [4- (acryloxy-polypropylene) Di (meth) acrylates of polyhydric alcohol ethylene oxide adducts or polyhydric alcohol propylene oxide adducts such as xyl) phenyl] propane; polyfunctional monomers having 3 or more (meth) acryloyl groups in one molecule be able to.

  The photopolymerizable polyfunctional monomer is preferably an ester of a polyhydric alcohol and (meth) acrylic acid as in these specific examples, and has 3 or more (meth) acryloyl groups in one molecule. The polyfunctional monomer having is more preferable. Specific examples of the polyfunctional monomer having 3 or more (meth) acryloyl groups in one molecule include trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, 1,2,4- Cyclohexanetetra (meth) acrylate, pentaglycerol triacrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol tetra (meth) acrylate, di Examples include pentaerythritol hexa (meth) acrylate, tripentaerythritol triacrylate, and tripentaerythritol hexaacrylate. Two or more kinds of the photopolymerizable polyfunctional monomers may be used in combination.

  Further, the ionizing radiation polymerizable polyfunctional monomer or polyfunctional prepolymer is preferably used as the ionizing radiation polymerizable monomer, but the photopolymerizable monofunctional monomer having one photopolymerizable functional group is used. A monomer may be used in combination. Examples of the photopolymerizable monofunctional monomer include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate. , Isobutyl (meth) acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, isononyl (meth) acrylate, ( Isodecyl (meth) acrylate, isoundecyl (meth) acrylate, n-dodecyl (meth) acrylate, isododecyl (meth) acrylate, isotridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, (meth) acrylic acid n-hexadecyl, n-octadecyl (meth) acrylate, (meth) acrylic acid Sooctadecyl, n-icosyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, 4-tert-butylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, (meta ) Dicyclopentenyloxyethyl acrylate, isobornyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, 2-acetoacetoxyethyl (meth) acrylate, 4-acetoacetoxybutyl (meth) acrylate, (meth ) Alkyl (meth) acrylates such as benzyl acrylate, 2-chloroethyl acrylate, glycidyl (meth) acrylate, 4-hydroxybutyl glycidyl ether (meth) acrylate (alkyl (meth) acrylate, or (meta ) Induction of alkyl acrylate (Which are neither hydroxyalkyl (meth) acrylates nor alkyl (meth) acrylates containing nitrogen atoms); (meth) such as (meth) acrylate oleyl, (meth) acrylate dicyclopentenyl Alkenyl acrylates; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, (meth) acrylic acid Hydroxyalkyl (meth) acrylates such as caprolactone (eg, dicaprolactone-modified 2-hydroxyethyl (meth) acrylate), polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, glyceryl (meth) acrylate; (Meth) acrylic Mido, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-butyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl ( (Meth) acrylamide, N, N-dipropyl (meth) acrylamide, N, N-dibutyl (meth) acrylamide, N-methyl-N-ethyl (meth) acrylamide, N-methyl-N-propyl (meth) acrylamide, N- Methyl-N-butyl (meth) acrylamide, N-ethyl-N-propyl (meth) acrylamide, N-ethyl-N-butyl (meth) acrylamide, N-propyl-N-butyl (meth) acrylamide, N-methylol ( (Meth) acrylamide, N-hydroxyethyl (meth) acryl Mido, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, acryloylmorpholine, diacetone acrylamide, methyl (meth) acrylamide glycolate methyl ether, etc. (Meth) acrylamides; 2,2,6,6-tetramethylpiperidyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylamino (meth) acrylate, carbodiimidoethyl (meth) acrylate , Alkyl (meth) acrylates containing nitrogen atom, such as tert-butylcarbodiimidoethyl (meth) acrylate, N-acryloyloxyethyl hexahydrophthalimide; 2-vinylpyridine, 4-vinyl Nitrogen-containing heterocyclic compounds in which hydrogen on a carbon atom is substituted with a vinyl group, such as pyridine; N-vinylpyrrolidone, N-vinyl-ε-caprolactam, N-vinylformamide, N-vinylacetamide, 1-vinyl N-vinyl compounds such as imidazole; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl pivalate, vinyl caproate, vinyl caprate, vinyl 2-ethylhexanoate, vinyl laurate, vinyl myristate, palmitate Vinyl acetate, vinyl stearate, vinyl versatate (for example, “Beoba (registered trademark)” (trade name) manufactured by Mitsubishi Chemical Corporation), vinyl carboxylates such as vinyl benzoate; 2-acetoacetoxyethyl vinyl ether, 4-acetoacetoxybutyl vinyl ether, propyl vinyl Vinyl ethers such as ether, isopropyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexyl vinyl ether, 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether, cyclohexanedimethanol monovinyl ether; styrene, α-methyl Aromatic vinyls such as styrene, β-methylstyrene, 4-methylstyrene, aminostyrene; 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 3- (meth) Acryloyloxypropyldimethoxymethylsilane, 3- (meth) acryloyloxypropyldiethoxymethylsila , Tetrahydrofurfuryl (meth) acrylate, cyclohexyl maleimide, and isopropyl maleimide, other monofunctional monomers, and the like.

  The ionizing radiation curable resin includes acrylic resin (a homopolymer or copolymer obtained by polymerizing the (meth) acrylic acid ester monomer), rubber resin (polyisoprene, polybutadiene, etc.), charging Inhibitor, slip agent (silicone slip agent, fluorine slip agent, etc.), leveling agent, antioxidant, anti-aging agent, UV absorber, light stabilizer, plasticizer, viscosity modifier, bactericidal agent, antibacterial agent, You may use together additives, such as a coloring agent.

  When the photopolymerizable polyfunctional monomer or photopolymerizable polyfunctional prepolymer is used as the ionizing radiation polymerizable monomer or ionizing radiation polymerizable prepolymer, a photopolymerization initiator is used as the ionizing radiation polymerization initiator. It is preferable to use as. As the photopolymerization initiator, a photoradical polymerization initiator or a photocationic polymerization initiator is preferable, and a photoradical polymerization initiator is particularly preferable.

  Examples of the photo radical polymerization initiator include acetophenones, benzoins, benzophenones, phosphine oxides, ketals, α-hydroxyalkylphenones, α-aminoalkylphenones, anthraquinones, thioxanthones, azo compounds, peroxides (Described in JP 2001-139663 A, etc.), 2,3-dialkyldione compounds, disulfide compounds, fluoroamine compounds, aromatic sulfoniums, onium salts, borate salts, active halogen compounds, α-acyloxy Muester and the like.

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

  Commercially available photocleavable photoradical polymerization initiators include trade names “Irgacure (registered trademark) 651” (2,2-dimethoxy-1,2-diphenylethane-1-one) manufactured by BASF Japan Ltd., BASF Trade name “Irgacure (registered trademark) 184” (1-hydroxycyclohexyl phenyl ketone) manufactured by Japan Co., Ltd., trade name “Irgacure (registered trademark) 907” (2-methyl-1- [4- (Methylthio) phenyl] -2- (4-morpholinyl) -1-propanone) and the like are preferable examples.

  The photopolymerization initiator is preferably used within a range of 0.1 to 15 parts by weight with respect to 100 parts by weight of the photopolymerizable polyfunctional monomer or photopolymerizable polyfunctional prepolymer. More preferably, it is used within the range of 10 parts by weight.

  In the polymerization of the photopolymerizable polyfunctional monomer or photopolymerizable polyfunctional prepolymer, a reaction accelerator may be used in addition to the photopolymerization initiator. Specific examples of the reaction accelerator include n-butylamine, triethylamine, tri-n-butylphosphine, Michler's ketone, thioxanthones and the like.

  In the polymerization of the photopolymerizable polyfunctional monomer or photopolymerizable polyfunctional prepolymer, a photosensitizer may be used in addition to the photopolymerization initiator. Specific examples of the photosensitizer include those having a benzene ring, such as benzophenone, anthraquinone, and 9,10-dibutoxyanthracene.

  When obtaining the coating material from the resin particle solvent dispersion, an organic solvent may be added to dilute the solid content concentration. When an organic solvent is added, the SP value of the organic solvent contained in the paint may be in the range of 8.0 to 12.5.

[How to use paint]
After the coating material was applied on the base film, the coating material was cured to form a coating film on the base film, and the coating film was formed on at least one surface of the base film. A laminated film (resin film) can be obtained.

  The base film is made of a resin material. Although it does not specifically limit as said resin material, A general material can be used, For example, a cellulose acylate, the said acrylic resin ((meth) acrylate type polymer), acrylonitrile styrene copolymer resin (AS), acrylonitrile -Acrylic rubber-styrene copolymer resin (AAS), acrylonitrile-butadiene-styrene copolymer resin (ABS), cyclic olefin copolymer (COC), cyclic olefin polymer (COP), ethylene-vinyl alcohol copolymer resin (EVOH), ethylene -Vinyl acetate copolymer resin (EVA), epoxy resin (EP), methacryl-styrene copolymer resin (MS), polyarylate (PAR), polyethylene terephthalate (PET), polyethersulfone (PES), polypropylene (PP) Polystyrene (PS), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene naphthalate (PEN), hydrogenated styrene-butadiene-styrene block copolymer (SBS), polyamide (PA), polyethylene (PE), poly Examples include methylpentene (PMP), polysulfone (PSU), and low density polyethylene (LDPE). In the present specification, “(meth) acrylate” means acrylate and / or methacrylate.

  Examples of the cellulose acylate include cellulose triacetate, cellulose diacetate, and cellulose acetate butyrate. Examples of the acrylic resin include poly (meth) methyl acrylate, poly (meth) ethyl acrylate, methyl (meth) acrylate-butyl (meth) acrylate, and the like. Examples of the polyester include polyethylene terephthalate (hereinafter abbreviated as “PET”), polyethylene naphthalate, and the like. The thickness of the base film is preferably in the range of 20 to 300 μm, and more preferably in the range of 20 to 200 μm.

  As a method of applying the paint onto the base film, a bar coating method, a reverse roll coating method, a gravure coating method, a die coating method, a comma coating method, a spray coating method, or the like can be used.

  When the coating material contains an ionizing radiation curable resin, the coating material can be cured by irradiating the coating material with ionizing radiation (ultraviolet ray, electron beam, etc.). As a method of irradiating ionizing radiation, a method of irradiating ultraviolet rays in a wavelength region of 100 to 400 nm, preferably 200 to 400 nm emitted from an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a metal halide lamp, etc .; For example, a method of irradiating an electron beam having a wavelength region of less than 100 nm emitted from a curtain type electron beam accelerator can be used.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, this invention is not limited by these Examples. First, measurement method of volume average particle diameter of particles in slurry, calculation method and measurement method of glass transition temperature of polymer of monofunctional vinyl monomer, calculation method of SP value of organic solvent, resin particle solvent dispersion A method for measuring the apparent viscosity of the body, a method for evaluating the appearance of the resin particle solvent dispersion, and a method for measuring the average particle diameter of the resin particles and the coefficient of variation of the particle diameter in the resin particle solvent dispersion will be described.

[Measurement method of volume average particle size of particle in slurry and coefficient of variation of particle size]
The volume average particle diameter of particles (seed particles or resin particles) in the slurry in the following examples and comparative examples was measured as follows.

  The volume average particle diameter of the particles in the slurry is measured by a laser diffraction / scattering particle size distribution measuring device (“LS 13 320” manufactured by Beckman Coulter, Inc.) and a universal liquid sample module.

  For measurement, 0.5 g of a slurry containing particles was added to 10 ml of a 0.1% by weight nonionic surfactant aqueous solution by touch mixer (manufactured by Yamato Kagaku Co., Ltd., “TOUCHMIXER MT-31”) and ultrasonic cleaner (Co., Ltd.). A dispersion liquid is used by using “ULTRASONIC CLEANER VS-150” manufactured by Vervo Crea.

  In addition, in the laser diffraction / scattering type particle size distribution measuring device software described above, the following optical parameters required for evaluation based on the Mie theory are set.

<Parameter>
Refractive index of liquid (nonionic surfactant aqueous solution) I. Real part = 1.333 (refractive index of water)
Real part of refractive index of solid (particle to be measured) = refractive index of particle Imaginary part of refractive index of solid = 0
Solid form factor = 1
Measurement conditions and measurement procedures are as follows.

<Measurement conditions>
Measurement time: 60 seconds Number of measurements: 1
Pump speed: 50-60%
PIDS relative concentration: about 40-55% Ultrasonic output: 8
<Measurement procedure>
After performing offset measurement, optical axis adjustment, and background measurement, the above-described dispersion liquid is injected into the universal liquid sample module of the laser diffraction / scattering particle size distribution measuring apparatus using a dropper. When the concentration in the universal liquid sample module reaches the PIDS relative concentration and the software of the laser diffraction / scattering particle size distribution measuring apparatus displays “OK”, the measurement is started. Note that the measurement is performed in a state where the particles are dispersed by performing pump circulation in the universal liquid sample module and an ultrasonic unit (ULM ULTRASONIC MODULE) is activated.

  In addition, the measurement is performed at room temperature, and from the obtained data, the software of the laser diffraction / scattering type particle size distribution measuring apparatus is used to set the volume average particle diameter ( The arithmetic mean diameter in the volume-based particle size distribution) and the coefficient of variation of the particle diameter are calculated.

  In addition, about the refractive index of particle | grains, the refractive index of the polymer which comprises particle | grains was input, and the measurement was implemented.

[Calculation method and measurement method of glass transition temperature of polymer of monofunctional vinyl monomer]
In this application document, when the monofunctional vinyl monomer is a mixture of a plurality of types of monomers M1 to Mn (n represents the number of types of monomers constituting the mixture), the monofunctional vinyl monomer The glass transition temperature Tg (K) of the polymer (monomer M1 to Mn copolymer) of

Where Tg is the glass transition temperature (K) calculated for the copolymer of monomers M1 to Mn, and W _i is the weight fraction of the i th monomer M _i in the mixture. ,

In and, Tg _i is the i-th glass transition temperature of the homopolymer of monomer (K))
Shall be calculated by The glass transition temperature of the homopolymer is described, for example, in J. Org. Brandrup (brand wrap) and E.I. H. Immergut, “Polymer Handbook (Polymer Handbook)”, Interscience Publishers (Interscience Publishers). In the present specification, the glass transition temperature in ° C. was calculated by subtracting 273.15 from the glass transition temperature Tg (K) in K calculated by the Fox equation.

[Calculation method of SP value of organic solvent]
In this application document, the SP value of the organic solvent is determined by the method of Fedors [Robert F. Fedors, Polymer Engineering and Science, 14, 147-154 (1974)]. The SP value δ is calculated from the following formula δ = [ΣEcoh / ΣV] ^1/2 from the cohesive energy Ecoh [cal / mol] and the molar molecular volume V [cm ³ / mol] of the substituent.
Can be used to calculate. In the present application, the unit “(cal / cm ³ ) ^1/2 ” conventionally used is used as the SP value unit. This unit is expressed by the following formula 1 (cal / cm ³ ) ^1/2 = 2.05 (MPa) ^1/2
Can be converted into SI unit “(MPa) ^1/2 ”.

  When the organic solvent is a mixture of two or more kinds of components, the SP value of the organic solvent is defined by the following formula.

(In the above formula, n represents the number of components constituting the mixture, δ _i represents the SP value of the i-th component, φ _i represents the volume fraction of the i-th component, and V _i represents the represents the molar volume of the volume fraction of the i-th component)
The hexane SP value calculated by the Fedors method is 7.3 (cal / cm ³ ) ^1/2 , and the butyl acetate SP value calculated by the Fedors method is 8.7 (cal / cm ³ ) ^{1. / 2} , the SP value of acetone calculated by the Fedors method is 8.43 (cal / cm ³ ) ^1/2 , and the SP value of methyl ethyl ketone calculated by the Fedors method is 9.0 (cal / cm cm ³ ) ^1/2 , and the SP value of toluene calculated by the Fedors method is 9.1 (cal / cm ³ ) ^1/2 , and the SP value of ethanol calculated by the Fedors method is 10. 97 (cal / cm ³ ) ^1/2 , and the SP value of isopropyl alcohol calculated by the Fedors method is 11.5 (cal / cm ³ ) ^1/2, which is calculated by the Fedors method. The calculated SP value of ethylene glycol was 14.8 (cal / cm ³ ) ^1/2 .

[Measurement method of apparent viscosity of resin particle solvent dispersion]
In this application document, the apparent viscosity of the resin particle solvent dispersion when the amount of the organic solvent is adjusted so that the solid content concentration is 20% by weight is measured as follows.

  First, when the solid content concentration of the resin particle solvent dispersion is less than 20% by weight or more than 20% by weight, the resin particles solvent is added or removed by adding or removing the same organic solvent contained in the resin particle solvent dispersion. The solid content concentration of the dispersion is adjusted to 20% by weight, and the resin particle solvent dispersion after the solid content concentration adjustment is used as a sample. When the solid content concentration of the resin particle solvent dispersion is 20% by weight, the resin particle solvent dispersion is used as it is as a sample.

  The apparent viscosity of the sample (resin particle solvent dispersion) was determined in accordance with JIS K 7117-1: 1999 “Appendix 1 (Reference) Method for Measuring Viscosity Using SB Viscometer”, Brookfield Rotational Viscometer (Toki Sangyo Co., Ltd., BM type) is used for measurement.

When the viscosity of the sample is less than 90 mPa · s, No. No. 1 is used when the viscosity of the sample is 90 mPa · s or more and less than 450 mPa · s. No. 2 is used when the viscosity of the sample is 450 mPa · s or more and less than 1000 mPa · s. Use 3 spindles. 200 g of a sample (resin particle solvent dispersion) having a sample temperature of 20 ° C. was sampled in a glass bottle M225 having an inner volume of 230 ml, an outer diameter of 62 mm, and a height of about 109 mm, and the spindle was rotated at a spindle rotation speed of 60 min ^−1. The viscometer reading value (scale reading value) was read 1 minute after the start. The apparent viscosity was calculated from the following calculation formula described in “Appendix 1 (Reference) Viscosity Measurement Method Using SB Type Viscometer” of JIS K7117-1: 1999 from the indicated value of the viscometer.

η _a = K _n × θ
(Where η _a : apparent viscosity [mPa · s]
K _n : Conversion factor based on the combination of spindle speed and spindle number
θ: Viscometer reading value)
Conversion factor K _n is, No. When 1 spindle is used, 1 mPa · s, No. When 2 spindles are used, 5 mPa · s, No. When 3 spindles are used, 20 mPa · s is set.

[Measuring method of average particle diameter of resin particles in resin particle solvent dispersion and coefficient of variation of particle diameter]
The measurement of the average particle diameter of the resin particles in the resin particle solvent dispersion in Examples and Comparative Examples was performed as follows.

  The volume average particle diameter of the resin particles in the resin particle solvent dispersion was measured using a dynamic light scattering type particle size distribution measuring device (trade name “FPAR-1000” manufactured by Otsuka Electronics Co., Ltd.). As a sample to be measured, a resin particle solvent dispersion having a solid content concentration of 20% by weight used for measuring the viscosity was dissolved in the same organic solvent as the organic solvent in the resin particle solvent dispersion with a solid content concentration of 0.02% by weight. A dispersion obtained by diluting to a minimum was used.

  As the refractive index of the organic solvent, which is a parameter used for the histogram analysis of the dynamic light scattering particle size distribution measuring apparatus, when the organic solvent in the resin particle solvent dispersion is hexane, the refractive index of hexane = 1.375. When the organic solvent in the resin particle solvent dispersion is butyl acetate, the refractive index of butyl acetate = 1.394 is used, and when the organic solvent in the resin particle solvent dispersion is methyl ethyl ketone, When the refractive index of methyl ethyl ketone = 1.379 is used and the organic solvent in the resin particle solvent dispersion is isopropyl alcohol, the refractive index of isopropyl alcohol = 1.378 is used, and the organic solvent in the resin particle solvent dispersion is used. When the solvent was ethylene glycol, the refractive index of ethylene glycol = 1.432 was used.

  The measurement is performed using a dilute probe and the temperature of the dispersion (sample temperature) is 20 ° C., and the average particle diameter and standard deviation values in the histogram analysis result of the dynamic light scattering type particle size distribution analyzer are adopted. did.

The coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is expressed by the following formula: coefficient of variation of particle diameter [%] = (standard deviation [μm] / average of standard deviation and average particle diameter obtained by the above measurement) Particle diameter [μm]) × 100
It calculated using.

[Production Example 1] (Production of resin particles used in Examples by seed polymerization)
In an autoclave having an internal volume of 5 L equipped with a stirrer and a thermometer, 3200 parts by weight of water as an aqueous medium and sodium p-styrene sulfonate as a reactive anionic surfactant (trade name, manufactured by Tosoh Organic Chemical Co., Ltd.) 2.9 parts by weight of "Spinomer (R) NaSS") was supplied. Next, methyl methacrylate (manufactured by Mitsubishi Rayon Co., Ltd., trade name “Acryester (registered trademark)) as a monofunctional vinyl monomer (first vinyl monomer) prepared in advance in an autoclave. M ") A mixture of 800 parts by weight and 3 parts by weight of n-octyl mercaptan as a chain transfer agent was charged, and the contents of the autoclave were heated to 70 ° C with stirring while the inside of the autoclave was purged with nitrogen. Thereafter, the internal temperature of the autoclave was kept at 70 ° C., and 4 parts by weight of potassium persulfate as a polymerization initiator was added to the contents of the autoclave, followed by polymerization for 12 hours to obtain a slurry containing seed particles. The obtained slurry containing seed particles had a volume average particle diameter of 0.28 μm and a solid content concentration of 20% by weight.

  In a 5 L autoclave equipped with a stirrer and a thermometer, sodium polyoxyethylene alkylphenyl ether phosphate as a surfactant (trade name “phosphanol (registered trademark) LO-529, manufactured by Toho Chemical Co., Ltd.) ] 2700 parts by weight of a surfactant aqueous solution prepared in advance by dissolving 26.7 parts by weight in deionized water. Next, tert-butyl methacrylate as a monofunctional vinyl monomer prepared in advance (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”, glass transition temperature 107 of the homopolymer thereof into an autoclave. ° C) 910 parts by weight, 390 parts by weight of ethylene glycol dimethacrylate as a polyfunctional vinyl monomer, and 6.7 parts by weight of 2,2′-azobisisobutyronitrile as a polymerization initiator (Second vinyl monomer) was supplied, and the mixture was dispersed in an aqueous surfactant solution to obtain a dispersion. Next, the dispersion liquid is stirred with a high-speed emulsification / dispersing machine (trade name “TK homomixer MARK II 2.5 type”, manufactured by Primix Co., Ltd.), so that the droplet diameter of the mixed liquid is about 5 μm. Adjusted.

  Furthermore, 330 parts by weight of slurry containing seed particles was added to the dispersion liquid in the autoclave by batch charging, and the contents of the autoclave were stirred at 30 ° C. for 1 hour to allow the seed particles to absorb the mixed solution. The resulting mixture was then polymerized under a nitrogen stream at 50 ° C. for 2 hours with continued stirring (primary constant temperature). Subsequently, a treatment (secondary constant temperature) for maintaining the internal temperature of the autoclave at 80 ° C. was performed for 3 hours to obtain a slurry containing resin particles, and then the slurry was cooled to room temperature (about 25 ° C.). As a result of measuring the volume average particle diameter of the resin particles in the slurry after cooling, the volume average particle diameter of the resin particles in the slurry is 0.82 μm, and the variation coefficient of the particle diameter of the resin particles in the slurry is 13.4%. there were.

  The obtained slurry is classified by passing through a sieve screen having a mesh size of 400 μm to remove coarse particles, and then supplied with a spray dryer (temperature at the slurry inlet of the spray dryer) 180 ° C., exhaust temperature (spray dryer) The powder particle exit temperature) was spray-dried at 60 ° C. to obtain dry powder resin particles (1).

  In this production example, the ratio of the amount of methyl methacrylate to the amount of all components involved in the polymerization reaction among the raw materials used in the production of the resin particles (the structural unit derived from methyl methacrylate relative to the entire resin particles) 4.8% by weight), and the ratio of the amount of tert-butyl methacrylate to the amount of all components involved in the polymerization reaction among the raw materials used for the production of the resin particles (the whole resin particles Ethylene glycol with respect to the amount of all the components involved in the polymerization reaction among the raw materials used for the production of the resin particles is 66.3% by weight, corresponding to the proportion of the amount of structural units derived from tert-butyl methacrylate relative to The proportion of the amount of dimethacrylate (corresponding to the proportion of the amount of structural units derived from ethylene glycol dimethacrylate with respect to the entire resin particles) is 28. In weight percent.

[Production Example 2] (Production of resin particles used in Examples by emulsion polymerization)
In an autoclave having an internal volume of 5 L equipped with a stirrer and a thermometer, 3200 parts by weight of water as an aqueous medium and polyoxyethylene alkyl ether sulfate as a reactive anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd.) , 2.25 parts by weight (trade name “AQUALON (registered trademark) KH-1025”; pure content 25% by weight) was supplied (0.07 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture). Next, 640 parts by weight of tert-butyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”) prepared in advance in an autoclave and allyl methacrylate as a polyfunctional vinyl monomer (Mitsubishi) A liquid mixture (polymerizable monomer mixture) with 160 parts by weight of Rayon Co., Ltd. (trade name “Acryester (registered trademark) A”) was supplied. The contents of the autoclave were heated to 70 ° C. while stirring at a stirring speed of 200 rpm. Next, after supplying 8.0 parts by weight of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator, emulsion polymerization was performed while continuing stirring at 70 ° C. for 2 hours (primary Constant temperature). Subsequently, a treatment (secondary constant temperature) for maintaining the internal temperature of the autoclave at 80 ° C. was performed for 1 hour to obtain a slurry containing resin particles, and then the slurry was cooled to room temperature (about 25 ° C.). As a result of measuring the volume average particle diameter of the resin particles in the slurry after cooling, the volume average particle diameter of the resin particles in the slurry is 0.31 μm, and the variation coefficient of the particle diameter of the resin particles in the slurry is 15.2%. there were.

  The obtained slurry was cooled and filtered in the same manner as in Production Example 1, and then spray-dried in the same manner as in Production Example 1 except that the supply air temperature was changed to 110 ° C. )

  In this production example, the ratio of the amount of tert-butyl methacrylate to the amount of all components involved in the polymerization reaction among the raw materials used for the production of the resin particles was 79.2% by weight, The ratio of the amount of allyl acid is 19.8% by weight.

[Production Example 3] (Production of resin particles used in Examples by emulsion polymerization)
In an autoclave having an internal volume of 5 L equipped with a stirrer and a thermometer, 3200 parts by weight of water as an aqueous medium, hydroxyethyl cellulose as a polymerization dispersant (trade name “HEC Daicel (registered trademark) SP-200, manufactured by Daicel Finechem Co., Ltd.) )) 0.8 parts by weight and 0.16 parts by weight of sodium p-styrene sulfonate (trade name “Spinomer (registered trademark) NaSS” manufactured by Tosoh Organic Chemical Co., Ltd.) as a reactive surfactant were stirred. And dissolved. Next, 560 parts by weight of isobutyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester IB”, glass transition temperature of its homopolymer 48 ° C.) prepared in advance in an autoclave and a polyfunctional vinyl-based unit A mixed solution of 240 parts by weight of ethylene glycol dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester EG”) as a monomer was supplied. The contents of the autoclave were heated to 70 ° C. while stirring at a stirring speed of 200 rpm. Next, after supplying 4.0 parts by weight of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator into the autoclave, emulsion polymerization was performed while continuing stirring at 70 ° C. for 2 hours (1 Next constant temperature). Subsequently, a treatment (secondary constant temperature) for maintaining the internal temperature of the autoclave at 80 ° C. was performed for 1 hour to obtain a slurry containing resin particles, and then the slurry was cooled to room temperature (about 25 ° C.). As a result of measuring the volume average particle diameter of the resin particles in the slurry after cooling, the volume average particle diameter of the resin particles in the slurry is 0.51 μm, and the variation coefficient of the particle diameter of the resin particles in the slurry is 14.1%. there were.

  The obtained slurry was cooled, filtered, and spray-dried in the same manner as in Production Example 2 to obtain dry powder resin particles (3).

  In this production example, the ratio of the amount of isobutyl methacrylate to the amount of all components involved in the polymerization reaction among the raw materials used for the production of the resin particles was 69.6% by weight, allyl methacrylate. The proportion of the amount is 29.8% by weight.

[Production Example 4] (Production of resin particles used in Comparative Example)
Other than using methyl methacrylate (Mitsubishi Rayon Co., Ltd., trade name “Acryester (registered trademark) M)” instead of tert-butyl methacrylate (Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”) Was similar to Production Example 2 to obtain a slurry containing resin particles. The volume average particle diameter of the resin particles in the obtained slurry was 0.29 μm, and the variation coefficient of the particle diameter of the resin particles in the obtained slurry was 15.7%.

  The obtained slurry was cooled, filtered, and spray-dried in the same manner as in Production Example 2 to obtain dry powder resin particles (4).

  In this production example, the ratio of the amount of methyl methacrylate to 79.2% by weight, allyl methacrylate, relative to the amount of all components involved in the polymerization reaction among the raw materials used for the production of the resin particles, The proportion of the amount is 19.8% by weight.

[Production Example 5] (Production of resin particles used in Comparative Example)
Methyl methacrylate (Mitsubishi Rayon Co., Ltd., trade name “Acryester (registered trademark) M”) alone instead of 910 parts by weight of tert-butyl methacrylate (Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”) Except that 780 parts by weight of the glass transition temperature of the polymer (105 ° C.) and 130 parts by weight of tert-butyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”) were used in the same manner as in Production Example 1. A slurry containing resin particles was obtained. The volume average particle diameter of the resin particles in the obtained slurry was 0.81 μm, and the variation coefficient of the particle diameter of the resin particles in the obtained slurry was 14.1%.

  The obtained slurry was cooled, filtered, and spray-dried in the same manner as in Production Example 2 to obtain dry powder resin particles (5).

  In this production example, the ratio of the amount of methyl methacrylate to 61.6% by weight of methacrylic acid tert with respect to the amount of all the components involved in the polymerization reaction among the raw materials used for the production of the resin particles The proportion of the amount of butyl is 9.5% by weight and the proportion of the amount of ethylene glycol dimethacrylate is 28.4% by weight. The glass transition temperature of the polymer of the monofunctional vinyl monomer contained in the mixed liquid (second vinyl monomer) absorbed by the seed particles is 105 ° C.

[Production Example 6] (Production of resin particles used in Comparative Example)
Instead of 910 parts by weight of tert-butyl methacrylate (Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”) and 390 parts by weight of ethylene glycol dimethacrylate, methyl methacrylate (Mitsubishi Rayon Co., Ltd., trade name “Acryester” (Registered trademark) M ") 300 parts by weight, tert-butyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name" Light Ester TB ") 840 parts by weight, and ethylene glycol dimethacrylate 60 parts by weight, In the same manner as in Production Example 1, a slurry containing resin particles was obtained. As a result of measuring the volume average particle diameter of the resin particles in the slurry, the volume average particle diameter of the resin particles in the slurry was 0.82 μm, and the coefficient of variation of the particle diameter of the resin particles in the slurry was 13.7%.

  The obtained slurry was cooled, filtered, and spray-dried in the same manner as in Production Example 2 to obtain dry powder resin particles (6).

  In this production example, the ratio of the amount of methyl methacrylate to 28.7% by weight of the amount of all components involved in the polymerization reaction among the raw materials used for the production of the resin particles was tert-methacrylic acid. The proportion of the amount of butyl is 66.0% by weight and the proportion of the amount of ethylene glycol dimethacrylate is 4.7% by weight. The glass transition temperature of the polymer of the monofunctional vinyl monomer contained in the mixed liquid (second vinyl monomer) absorbed by the seed particles is 106 ° C.

[Production Example 7] (Production of resin particles used in Comparative Example)
In a 5 L reaction vessel equipped with a stirrer having a V paddle type stirring blade, 2700 parts by weight of water, 265.2 parts by weight of magnesium pyrophosphate, sodium polyoxyethylene alkylphenyl ether phosphate (Toho Chemical Industries) 27.0 parts by weight of a product name “Fosphanol (registered trademark) LO-529” manufactured by Co., Ltd. was added.

  Moreover, 910 parts by weight of tert-butyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”), 390 parts by weight of ethylene glycol dimethacrylate as a polyfunctional vinyl monomer, and 2 as a polymerization initiator A monomer solution was obtained by mixing and dissolving 10.4 parts by weight of 2,2'-azobisisobutyronitrile.

Next, the monomer solution was added to the reaction vessel to obtain a monomer mixture. The monomer mixture is stirred for 20 minutes at a stirring speed of 10,000 rpm using a high-speed emulsification / dispersing machine (trade name “TK homomixer MARK II 2.5 type”, manufactured by Primix Co., Ltd.). The monomer solution was dispersed into droplets of about 5 μm. The monomer mixture was further passed once through a microfluidizer (model number “HC-5000”, manufactured by Mizuho Kogyo Co., Ltd.) under a pressure of 100 kg / cm ² to obtain a refined aqueous emulsion. The resulting aqueous emulsion was then polymerized under a nitrogen stream at 50 ° C. for 2 hours with continued stirring. Subsequently, a treatment (secondary constant temperature) for maintaining the internal temperature of the reaction vessel at 105 ° C. was performed for 1 hour to obtain a slurry containing resin particles, and then the slurry was cooled to room temperature (about 25 ° C.).

  The volume average particle diameter of the resin particles in the cooled slurry was 2.2 μm, and the coefficient of variation was 14.1%.

  200 parts by weight of 20% strength by weight hydrochloric acid was added to the slurry to decompose magnesium pyrophosphate, and then washed with water. It vacuum-dried at 60 degreeC with the dryer for 15 hours. After drying, coarse particles were removed by classification through a sieve mesh having a mesh size of 400 mesh to obtain resin particles (7) as a dry powder.

  In this production example, the ratio of the amount of tert-butyl methacrylate to the amount of all components involved in the polymerization reaction among the raw materials used for the production of the resin particles was 68.0% by weight, ethylene The proportion of the amount of glycol dimethacrylate is 29.2% by weight.

  Composition of monomers (monofunctional vinyl monomer and polyfunctional vinyl monomer) used in Production Examples 1 to 7, glass transition temperature of polymer of monofunctional vinyl monomer, Production Example 1 Table 1 shows the volume average particle size and the coefficient of variation of the particle size of the resin particles in the slurry of the resin particles obtained in -7. In the columns of Production Examples 1, 5, and 6 (Production Examples using Seed Polymerization) in Table 1, the mixed liquid absorbed in the seed particles as the glass transition temperature of the polymer of the monofunctional vinyl monomer. The glass transition temperature of the polymer of the monofunctional vinyl-type monomer contained in (2nd vinyl-type monomer) is shown.

[Production Example 8] (Production of resin particles used in Examples by emulsion polymerization)
In an autoclave having an internal volume of 5 L equipped with a stirrer and a thermometer, 3200 parts by weight of water as an aqueous medium and polyoxyethylene alkyl ether sulfate as a reactive anionic surfactant (Daiichi Kogyo Seiyaku Co., Ltd.) , 4.16 parts by weight (0.13 parts by weight with respect to 100 parts by weight of the polymerizable monomer mixture) of trade name “AQUALON (registered trademark) KH-1025”; Next, 640 parts by weight of tert-butyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name “Light Ester TB”) prepared in advance in an autoclave and allyl methacrylate as a polyfunctional vinyl monomer (Mitsubishi) A liquid mixture (polymerizable monomer mixture) with 160 parts by weight of Rayon Co., Ltd. (trade name “Acryester (registered trademark) A”) was supplied. The contents of the autoclave were heated to 70 ° C. while stirring at a stirring speed of 200 rpm. Next, after supplying 8.0 parts by weight of ammonium persulfate (manufactured by Wako Pure Chemical Industries, Ltd.) as a polymerization initiator, emulsion polymerization was performed while continuing stirring at 70 ° C. for 2 hours (primary Constant temperature). Subsequently, a treatment (secondary constant temperature) for maintaining the internal temperature of the autoclave at 80 ° C. was performed for 1 hour to obtain a slurry containing resin particles, and then the slurry was cooled to room temperature (about 25 ° C.). As a result of measuring the volume average particle diameter of the resin particles in the slurry after cooling, the volume average particle diameter of the resin particles in the slurry is 0.19 μm, and the coefficient of variation of the particle diameter of the resin particles in the slurry is 15.8%. there were.

[Example 1] (Production of resin particle solvent dispersion)
960 parts by weight of butyl acetate as an organic solvent (80% by weight with respect to 100% by weight of the resin particle solvent dispersion) with respect to a stainless steel (SUS) beaker having an internal volume of 2 liters was obtained in Production Example 1. 240 parts by weight of resin particles (1) (20% by weight with respect to 100% by weight of the resin particle solvent dispersion) was supplied and pre-stirred to obtain a mixture. Thereafter, the obtained mixture was stirred for about 20 minutes at a stirring speed of 6000 rpm using a high-speed emulsification / dispersing machine (trade name “TK. Homomixer MARK II 2.5 type”, manufactured by Primix Co., Ltd.). (1) was dispersed in an organic solvent to obtain a resin particle solvent dispersion having a solid content concentration (resin particle content) of 20% by weight.

  The obtained resin particle solvent dispersion was well dispersed in the organic solvent without the resin particles aggregating or swelling. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.78 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 13.4%, and the apparent viscosity of the resin particle solvent dispersion is 4. 0 mPa · s.

[Example 2] (Production of resin particle solvent dispersion)
A resin particle solvent dispersion having a solid content concentration of 20% by weight was obtained in the same manner as in Example 1 except that methyl ethyl ketone was used in place of butyl acetate as the organic solvent.

  The obtained resin particle solvent dispersion was well dispersed in the organic solvent without the resin particles aggregating or swelling. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.83 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 12.9%, and the apparent viscosity of the resin particle solvent dispersion is 3. 2 mPa · s.

[Example 3] (Production of resin particle solvent dispersion)
A resin particle solvent dispersion having a solid content concentration of 20% by weight was obtained in the same manner as in Example 1 except that isopropyl alcohol was used instead of butyl acetate as the organic solvent.

  The obtained resin particle solvent dispersion was well dispersed without the resin particles being aggregated or swollen. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.81 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 14.1%, and the apparent viscosity of the resin particle solvent dispersion is 16. 0 mPa · s.

[Example 4] (Production of resin particle solvent dispersion)
A solid content concentration of 20% by weight was obtained in the same manner as in Example 1 except that the resin particles (2) obtained in Production Example 2 were used instead of the resin particles (1) obtained in Production Example 1. A resin particle solvent dispersion was obtained.

  The obtained resin particle solvent dispersion was well dispersed without the resin particles being aggregated or swollen. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.35 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 10.4%, and the apparent viscosity of the resin particle solvent dispersion is 16. 1 mPa · s.

[Example 5] (Production of resin particle solvent dispersion)
A solid content concentration of 20 wt% was obtained in the same manner as in Example 1 except that the resin particles (3) obtained in Production Example 3 were used in place of the resin particles (1) obtained in Production Example 1. A resin particle solvent dispersion was obtained.

  The obtained resin particle solvent dispersion was well dispersed without the resin particles being aggregated or swollen. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.55 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 14.4%, and the apparent viscosity of the resin particle solvent dispersion is 14. 3 mPa · s.

[Example 6] (Production of resin particle solvent dispersion)
A solid content concentration of 20% by weight was obtained in the same manner as in Example 1 except that the resin particles (8) obtained in Production Example 8 were used in place of the resin particles (1) obtained in Production Example 1. A resin particle solvent dispersion was obtained.

  The obtained resin particle solvent dispersion was well dispersed without the resin particles being aggregated or swollen. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.19 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 16.8%, and the apparent viscosity of the resin particle solvent dispersion is 5. It was 5 mPa · s.

[Example 7] (Production of resin particle solvent dispersion)
As in Example 4, except that a mixed solvent of acetone / ethanol = 80/20 (volume ratio) (SP value 8.9 (cal / cm ³ ) ^1/2 ) was used as the organic solvent instead of butyl acetate. Thus, a resin particle solvent dispersion having a solid content concentration of 20% by weight was obtained.

  The obtained resin particle solvent dispersion was well dispersed in the organic solvent without the resin particles aggregating or swelling. The average particle diameter of the resin particles in the resin particle solvent dispersion is 0.34 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 11.0%, and the apparent viscosity of the resin particle solvent dispersion is 14. It was 9 mPa · s.

[Comparative Example 1] (Production of resin particle solvent dispersion)
A resin particle solvent dispersion having a solid content concentration of 20% by weight was obtained in the same manner as in Example 1 except that hexane was used instead of butyl acetate as the organic solvent.

  In the obtained resin particle solvent dispersion, resin particles were aggregated. The average particle diameter of the resin particles in the resin particle solvent dispersion is 2.22 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 20.2%, and the apparent viscosity of the resin particle solvent dispersion is 225 mPa · s.

[Comparative Example 2] (Production of resin particle solvent dispersion)
A resin particle solvent dispersion having a solid content concentration of 20% by weight was obtained in the same manner as in Example 1 except that ethylene glycol was used in place of butyl acetate as the organic solvent.

  In the obtained resin particle solvent dispersion, resin particles were aggregated. The average particle diameter of the resin particles in the resin particle solvent dispersion is 3.61 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 28.2%, and the apparent viscosity of the resin particle solvent dispersion is 480 mPa · s.

[Comparative Example 3] (Production of resin particle solvent dispersion)
A solid content concentration of 20% by weight was obtained in the same manner as in Example 2 except that the resin particles (4) obtained in Production Example 4 were used instead of the resin particles (2) obtained in Production Example 2. A resin particle solvent dispersion was obtained.

  In the obtained resin particle solvent dispersion, resin particles were aggregated. The average particle diameter of the resin particles in the resin particle solvent dispersion is 3.01 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 35.5%, and the apparent viscosity of the resin particle solvent dispersion is 345 mPa · s.

[Comparative Example 4] (Production of resin particle solvent dispersion)
A solid content concentration of 20% by weight was obtained in the same manner as in Example 2 except that the resin particles (5) obtained in Production Example 5 were used instead of the resin particles (2) obtained in Production Example 2. A resin particle solvent dispersion was obtained.

  In the obtained resin particle solvent dispersion, resin particles were aggregated. The average particle diameter of the resin particles in the resin particle solvent dispersion is 5.13 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 27.3%, and the apparent viscosity of the resin particle solvent dispersion is 132 mPa · s.

[Comparative Example 5] (Production of resin particle solvent dispersion)
A solid content concentration of 20% by weight was obtained in the same manner as in Example 2 except that the resin particles (6) obtained in Production Example 6 were used instead of the resin particles (2) obtained in Production Example 2. A resin particle solvent dispersion was obtained.

  In the obtained resin particle solvent dispersion, the resin particles were swollen. The average particle diameter of the resin particles in the resin particle solvent dispersion is 1.57 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 18.6%, and the apparent viscosity of the resin particle solvent dispersion is 652 mPa · s.

[Comparative Example 6] (Production of resin particle solvent dispersion)
A solid content concentration of 20% by weight was obtained in the same manner as in Example 2 except that the resin particles (7) obtained in Production Example 7 were used instead of the resin particles (2) obtained in Production Example 2. A resin particle solvent dispersion was obtained.

  The average particle diameter of the resin particles in the resin particle solvent dispersion is 2.56 μm, the coefficient of variation of the particle diameter of the resin particles in the resin particle solvent dispersion is 30.2%, and the apparent viscosity of the resin particle solvent dispersion is 180 mPa · s.

[Production example of hard coat layer]
Using each of the resin particle solvent dispersions obtained in Examples 1 to 5 and Comparative Examples 1 to 6, 11 types of hard coat layers were produced by the following method.

  Namely, 98.5 parts by weight of pentaerythritol triacrylate (trade name “Light Acrylate PE-3A”, manufactured by Kyoeisha Chemical Co., Ltd.) as a photopolymerizable polyfunctional monomer was added to 1-hydroxy as a radical photopolymerization initiator. A monomer composition was prepared by dissolving 1.5 parts by weight of cyclohexyl phenyl ketone (trade name “Irgacure (registered trademark) 184”, manufactured by BASF Japan Ltd.). Any one of the resin particle solvent dispersions obtained in Examples 1 to 5 and Comparative Examples 1 to 6 was mixed so that the amount of the resin particles relative to 100 parts by weight of the monomer composition was 0.25 parts by weight. Furthermore, it diluted with toluene so that solid content concentration might be 30 weight%, and obtained the coating liquid (paint).

  The obtained coating solution was applied onto a PET film (thickness 125 μm) as a transparent substrate so as to have a thickness of 5 μm by a bar coating method. The applied coating solution was dried at 80 ° C. for 3 minutes to form a coating layer. Next, the coating layer was cured by irradiating the coating layer with ultraviolet rays with a halogen lamp to form a hard coat layer (coating film). Thereby, a laminated film in which a hard coat layer (thickness: 5 μm) containing resin particles that can function as an antiblocking agent was formed on the PET film was obtained.

[Evaluation method of scratch resistance of hard coat layer]
The 11 types of hard coat layers obtained from the resin particle solvent dispersions of Examples 1 to 5 and Comparative Examples 1 to 6 were evaluated for scratch resistance by the following method.

Using a friction fastness tester (manufactured by Daiei Kagaku Seiki Seisakusho Co., Ltd., model number “RT-200”), one sample of a PET film not coated with the same hard coat as used in the production example of the hard coat layer The laminated film obtained in the production example of the hard coat layer was fixed to the upper surface of the table, and fixed to the lower surface of the friction element with the hard coat layer containing the resin particles facing downward. Further, a 500 g weight (contact area with the laminated film is 4 cm ² ) is placed on the laminated film, and the friction element is moved at a speed of 30 reciprocations / minute, at a distance of 10 cm in parallel with the longitudinal direction of the PET film 20 times. The PET film was rubbed with the hard coat layer of the laminated film by reciprocating, the haze difference (ΔH) of the PET film before and after the rub was measured, and this measured value was used as an evaluation index for scratch resistance. The haze was measured according to JIS K 7136 using a Nippon Denshoku Industries Co., Ltd. haze meter (model number “NDH 2000”).

  Further, the degree of scratches on the surface of the PET film after rubbing was observed with the naked eye. When the scratch was not confirmed with the naked eye, the scratch resistance (appearance) was determined to be “◯” (good), and when the scratch was confirmed, the scratch resistance (appearance) was determined to be “x” (poor).

[Evaluation method for blocking resistance of hard coat layer]
About 11 types of hard-coat layers obtained from each of the resin particle solvent dispersion of Examples 1-5 and Comparative Examples 1-6, blocking resistance was evaluated by the following method.

The laminated film obtained in the production example of the hard coat layer was formed into a 15 cm × 15 cm square, and was stacked so that the hard coat layer faced in the same direction, and sandwiched between two glass plates. The laminate film sandwiched between the two glass plates was allowed to stand for 24 hours in a 25 ° C. atmosphere while applying pressure so that the load was 50 g / cm ² . Then, it is visually evaluated whether the hard coat layer is blocking. When the hard coat layer is not blocked, the hard coat layer has a blocking resistance of “◯” (good), and the hard coat layer is blocked. The blocking resistance of the coating layer was “x” (poor).

  The evaluation results of scratch resistance and blocking resistance of 11 types of hard coat layers obtained from each of the resin particle solvent dispersions of Examples 1 to 5 and Comparative Examples 1 to 6 are shown in Examples 1 to 5 and Comparative Examples. Table 2 shows the composition and properties of the resin particle solvent dispersions 1 to 6.

  By comparing Examples 1 to 5 with Comparative Examples 1 and 2, the solubility parameter of the organic solvent is within the range of 8.0 to 12.5, so that the solubility parameter of the organic solvent is 8.0 to 12.5. It can be seen that the apparent viscosity of the resin particle solvent dispersion can be lowered and the scratch resistance can be improved as compared with the case outside the above range.

  By comparing Example 2 with Comparative Examples 3 and 4, by using 60% by weight or more of isobutyl methacrylate and / or tert-butyl methacrylate as the monofunctional vinyl monomer with respect to the total amount of the resin particles. In the case where only a monofunctional vinyl monomer (methyl methacrylate) having higher hydrophilicity than isobutyl methacrylate and tert-butyl methacrylate is used (Comparative Example 3), or tert methacrylate as a monofunctional vinyl monomer. -The apparent viscosity of the resin particle solvent dispersion can be lowered and the scratch resistance is improved as compared with the case where butyl is used at less than 60% by weight based on the total amount of the resin particles (Comparative Example 4). You can see that

  A comparison between Example 2 and Comparative Example 5 shows that the amount of the polyfunctional vinyl monomer is not less than 15% by weight based on the total amount of the resin particles. It can be seen that the apparent viscosity of the resin particle solvent dispersion can be lowered and the scratch resistance can be improved as compared with the case of less than 15% by weight based on the total amount of particles.

  In comparison between Example 2 and Comparative Example 6, the average particle size of the resin particles in the resin particle solvent dispersion is 1 μm or less by setting the average particle size of the resin particles in the resin particle solvent dispersion to 1 μm or less. It can be seen that the apparent viscosity of the resin particle solvent dispersion can be lowered and the scratch resistance can be improved as compared with the case of exceeding 0.0 μm.

Claims (4)

An organic solvent,
Resin particle solvent dispersion containing resin particles dispersed in the organic solvent,
The average particle diameter of the resin particles in the resin particle solvent dispersion is in the range of 0.1 to 1.0 μm,
The resin particles contain 66.3 to 85% by weight of structural units derived from isobutyl methacrylate and / or tert-butyl methacrylate and 15 to 40% by weight of structural units derived from a polyfunctional vinyl monomer. ,
The resin particle solvent dispersion, wherein the solubility parameter of the organic solvent is in the range of 8.0 to 12.5.   2. The resin particle solvent dispersion according to claim 1, wherein the apparent viscosity is 100 mPa · s or less when the amount of the organic solvent is adjusted so that the solid content concentration is 20 wt%.   The resin particle solvent dispersion according to claim 1 or 2, which is used as an antiblocking agent for a resin film.   The coating material characterized by including the resin particle solvent dispersion of any one of Claims 1-3, and binder resin.