WO2008023648A1

WO2008023648A1 - Microparticle, process for producing microparticle, and, loaded with the microparticle, resin composition and optical film

Info

Publication number: WO2008023648A1
Application number: PCT/JP2007/066053
Authority: WO
Inventors: Kenji Shimizu; Miwako Tominaga; Shinji Takasaki; Shin-Ichi Horo
Original assignee: Nippon Shokubai Co., Ltd.
Priority date: 2006-08-21
Filing date: 2007-08-17
Publication date: 2008-02-28
Also published as: KR101382369B1; TW200819470A; CN101490138A; JP5478066B2; CN101490138B; KR20090033251A; KR20110133638A; JPWO2008023648A1

Abstract

Microparticles having the content of coarse particles exceeding the average particle diameter reduced to a low level; a process for producing such microparticles; and a resin composition containing the microparticles. The microparticles are characterized in that the content of coarse particles with a diameter of twice or more the average particle diameter is 1000 particles/0.5g or less. The process for producing the microparticles comprises the steps of wet classification of a microparticle dispersion liquid of 0.5 to 50 mass% solid content and 0.5 to 20 mass B-viscosity; drying and pulverization of the microparticles after the wet classification to thereby obtain powdery microparticles of 0.05 to 2 mass% water content; and dry classification of the powdery microparticles.

Description

Specification

Fine particle, method for producing fine particle, resin composition containing the fine particle, and optical finem

Technical field

The present invention relates to fine particles whose particle diameter is highly controlled, and a resin composition using the same.

Background art

Conventionally, there have been attempts to improve the physical properties or usefulness of resins and resin compositions by incorporating fine particles into resins and resin compositions used for various applications. Similar efforts are made for optical resin materials used in optical applications such as liquid crystal displays (LCDs), plasma display panels (PDPs), electoric luminescence displays (ELDs), transmissive screens and touch panels. For example, optical resin compositions containing fine particles made of organic materials or inorganic materials are used as raw materials for optical resin films (sheets, plates) that impart light diffusibility and antireflection antiglare properties. Being! /

[0003] By the way, in recent years, in the field of image display devices as described above, there has been a trend toward larger screens and higher definition, and the demand for peripheral technologies has increased. Various studies have been made such as improving the affinity with (resin and other additives) and improving the mechanical and optical properties of the fine particles themselves. In addition to the above required properties, the fine particles used as spacers for optical resin films and liquid crystal display elements have a narrow particle size distribution and a coarse particle content. Less is also desired. This is because when the particle size distribution is wide, it is difficult to maintain a uniform and constant liquid crystal film thickness when used as a spacer for a liquid crystal display device. Coarse particles cause scratches on the film surface. This is because the fine particles may be directly visually recognized and cause the display quality of the image display device to deteriorate.

[0004] For example, in Patent Document 1 that discloses fine particles used for optical applications, according to the method for producing the fine particles, particles having a particle size corresponding to a desired application can be obtained with a very sharp particle size distribution. It is stated that In Patent Documents 2 to 4, coarse particles are From the viewpoint of deteriorating display quality and causing defects in the optical film, a method for producing fine particles in which the content of particles having a particle size exceeding a predetermined size with respect to the average particle size is reduced (Patent Document 2), fine particles Prior to use, a method of removing coarse particles by subjecting the fine particles in the emulsion or dispersion state to filtration is proposed (Patent Documents 3 and 4). Patent Document 1: JP 2004-307644 A, etc.

Patent Document 2: JP-A-2002-166228, claims, etc.

Patent Document 3: JP-A-2005-309399, claims, etc.

Patent Document 4: Japanese Patent Application Laid-Open No. 2004-191956, Claims, etc.

Disclosure of the invention

[0005] However, as in Patent Document 1, it is actually difficult to control the particle size distribution at a high level in the fine particle synthesis stage, and as pointed out in Patent Documents 2 to 4. Even if the particle size distribution is controlled within a suitable range, if there are coarse particles that greatly deviate from the average particle size, the display quality is deteriorated and the optical film has a defect. Therefore, the demand for reducing the amount of coarse particles tends to increase further from the viewpoint of improving visibility and productivity, and even with the techniques of Patent Documents 2 to 4, fine particles that sufficiently satisfy such a demand can be obtained. It was difficult to get.

[0006] The present invention has been made paying attention to the above circumstances, and its object is to provide fine particles in which the content of coarse particles deviating from a suitable particle size is reduced to a low level, and such fine particles. It is in providing the manufacturing method of particle | grains, and the resin composition containing this microparticles | fine-particles.

[0007] The fine particles of the present invention that have solved the above problems are summarized in that the number of coarse particles having a particle size of twice or more the average particle size is 1000 particles / 0.5 g or less.

[0008] The fine particles are preferably an organic-inorganic composite including an organic polymer skeleton and a polysiloxane skeleton.

[0009] The method for producing fine particles of the present invention includes a step of wet-classifying a fine particle dispersion having a solid content concentration of 0.5 to 50% by mass and a B-type viscosity of 0.5 to 2 OmPa's, and fine particles after wet classification It is characterized in that it comprises a step of drying and pulverizing to form fine powder particles having a water content of 0.05-2 mass%, and a step of dry classification of the fine powder particles. In this way, raw materials (particulate dispersion, powder) having specific physical properties are treated by a method combining wet classification and dry classification. As a result, coarse particles and fine particles deviating from the preferred range of particle size can be reduced more efficiently.

[0010] Also included are compositions and optical films obtained by applying the coating composition on a substrate (films having an uneven shape on the surface, such as a light diffusion film and an antiglare film).

[0011] The fine particles of the present invention are those in which the content of coarse particles that deviate from the preferred range of particle size is reduced to a low level. Further, according to the method of the present invention, the content of fine particles can be reduced together with coarse particles that deviate from the preferred range of particle size. Therefore, it is considered that a molded product obtained from the resin composition containing the particles of the present invention is less prone to defects due to coarse particles. In addition, since the content of fine particles is reduced, it is considered that the transparency of the resin itself is hardly damaged. The fine particles of the present invention are particularly suitable for optical resin compositions, and the light diffusion film, antiglare film obtained from such resin composition, and the light diffusion plate containing the fine particles of the present invention are excellent. It is considered that the optical characteristics are exhibited.

BEST MODE FOR CARRYING OUT THE INVENTION

[0012] The fine particles of the present invention are characterized in that the number of coarse particles having a particle size of at least twice the average particle size is 1000 particles / 0.5 g or less.

[0013] As described above, if the fine particles used in the optical field include coarse particles that deviate from the preferred range of the particle size, there is a possibility that the film surface may be scratched or the fine particles are likely to be visually recognized. In particular, the present inventors have confirmed that the above phenomenon becomes remarkable when fine particles having a particle size of twice or more the average particle size of the fine particles used are present (increased). Preferably, 500 particles / 0.5 g or less of coarse particles having a particle size twice or more the average particle size, more preferably 200 solids / 0.5 g or less, and even more preferably 100 particles / 0.5 g Hereinafter, it is most preferably 50 pieces / 0.5 g or less.

[0014] Further, the amount of coarse particles within the above range and the number of coarse particles having a particle size of 2.5 times or more of the average particle size is 50 particles / 0.5 g or less is used for optical applications. In that case, it is preferable because defects due to coarse particles are less likely to occur. More preferably, it is 30 pieces / 0.5 g or less, and further preferably 10 pieces / 0.5 g or less.

[0015] In addition, the fine particles of the present invention preferably have a reduced number of fine particles having a particle size of 1/2 or less of the average particle size! /. It contains a lot of power and fine fine particles! When the fine particles are used for optical purposes (for example, a light diffusing film or an anti-glare anti-glare film provided on the image display surface of various image display devices), there is a possibility that transparency and luminance are lowered. Therefore, the fine particles having a particle size of 1/2 or less of the average particle size is preferably 10% by volume or less, more preferably 7% by volume or less.

[0016] The average particle size of the fine particles of the present invention is not particularly limited.

The force is preferably 50 μm S, more preferably;! To 30 μm, and even more preferably 2 to 20 μm. When the average particle diameter is within the above range, for example, when used in optical applications, advantageous effects such as excellent light diffusibility and surface light emission (brightness) can be obtained. If the average particle size is too small, the dispersibility of the resin serving as a medium may be reduced, and if it is too large, a sufficient light diffusion effect may not be obtained. In addition, the particle size distribution measurement, average particle diameter, and the content of the fine particles are determined using a precision particle size distribution measurement apparatus (for example, “Multisizer 11” manufactured by Beckman Coulter, Inc.) using the Coulter principle. And measured on a volume basis.

[0017] The shape of the fine particles of the present invention is not particularly limited, and examples thereof include a spherical shape, a needle shape, a plate shape, a scale shape, a pulverized shape, an uneven shape, an eyebrows shape, and a candy sugar shape. In particular, when used for optical applications (when used for optical resin compositions, etc.), the shape is a perfect sphere or nearly a perfect sphere, and the ratio of the long particle diameter to the short particle diameter is 1.0 to 1; 2 and the coefficient of variation of the particle diameter is preferably 10% or less.

[0018] The fine particles of the present invention are obtained by dry classification of fine powder particles having a predetermined water content, true specific gravity, bulk specific gravity, and particle diameter.

[0019] The powder particles subjected to the dry classification have a water content of 0.05 to 2% by mass. If the water content is too high, the force and moisture will act as a binder during classification and the particles will aggregate.On the other hand, if the water content is too low, the particles will aggregate due to static electricity. Even in the case of deviation, classification accuracy tends to be low and coarse particles tend to increase. If the water content is in the above range, the particles are difficult to aggregate, so that the classification operation can proceed smoothly. In addition, the true specific gravity is preferably 1 to; 1.25 g / ml, the bulk specific gravity is 0. !! to lg / ml, and the average particle size is preferably 1 to 50 m. If the true specific gravity of the powder particles is too small, the classification accuracy may be low because differences in centrifugal force and wind resistance due to the size of the particles are unlikely to occur. . If the true specific gravity is too large, large equipment and power are required, which is not preferable. On the other hand, when the bulk specific gravity is too large, large equipment and power are required, which is not preferable. On the other hand, when the bulk specific gravity is too small, a difference due to the size of the particle diameter hardly occurs, and classification accuracy may be lowered. If the particle size is too small, a good dispersion state in which the powders are strongly agglomerated may not be obtained, and the classification accuracy may decrease.If the particle size is too large, large equipment and power are required. Absent.

[0020] The content of coarse particles more than twice the average particle diameter in the powder particles subjected to dry classification by wet classification and in the dispersion obtained by wet classification is 200,000 or less per 0.5 g Is preferable. More preferably, it is 100,000 pieces / 0.5 g or less, and further preferably 50,000 pieces / 0.5 g or less. If the number of coarse particles of a specific size contained in the powder particles subjected to dry classification and the dispersion obtained by wet classification is within the above range, high yield and high yield can be achieved by performing dry classification. / Or preferred because it is easy to obtain fine particles with a small content of coarse particles at a high classification processing speed!

[0021] Therefore, the water content, true specific gravity, bulk specific gravity and particle diameter are preferably in the above ranges, more preferably the fine particles have a water content of 0 .;! To 0.5% by mass. The true specific gravity is;! ~ 1.5g / ml is preferred The bulk specific gravity is 0.3 ~ 0.8g / ml The preferred average particle diameter is 2 ~ 20m Preferably there is.

The “water content” is a value measured by a Karl Fischer moisture meter (for example, a moisture measuring device manufactured by Hiranuma Sangyo Co., Ltd.). The “bulk density” is the amount of powder that enters the container when the powder is placed in a constant volume container in a constant state, expressed as mass per unit volume. Measured with a powder tester (manufactured by Hosokawa Micron). The “true specific gravity” of fine powder particles means that fine powder particles are filled into a container of a certain volume, and the sample voids are completely replaced with liquid, and the volume of liquid required at this time is reduced by the volume capacity of the container. It is a value calculated from the relationship between the measured value and the mass of the fine powder particles filled in the container, and is measured by a true specific gravity measuring machine (for example, manufactured by Seishin Enterprise Co., Ltd.). The value of the particle size is a volume-based value measured by the precision particle size distribution measuring apparatus (for example, “Multisizer 1” manufactured by Beckman Coulter, Inc.).

[0023] For the dry classification of the fine powder particles, it is preferable to use an air classifier using wind power. Good. An air classifier is an apparatus that separates fine particles (powder layer) according to the particle size (particle size, mass) of the particles (ie, from the inertia of the particles and the air flow). The flying distance is determined and classified by the balance of drag force). Normally, in a classifier that uses only a sieve or a filter, the physical properties of the recovered particles depend on the sieve opening used and the filtration efficiency of the filter, so that the desired physical properties such as the particle diameter are within a specific range. In order to obtain only the contained particles, it is necessary to perform a plurality of classification operations. On the other hand, if an airflow classifier is used, coarse particles and fine particles can be removed simultaneously.

[0024] The classification mechanism of the airflow classifier is not particularly limited. Therefore, those that use only the airflow, those that have a rotating rotor that gives propulsive force to the airflow, and guide vanes that guide the wind, and that use the airflow generated by the combined action of these, and It can be combined with other classification means (sieves and meshes).

[0025] Specific airflow classifiers include high-precision airflow classifiers such as the DXF type (manufactured by Nippon Pneumatic Kogyo Co., Ltd.); (Registered trademark, manufactured by Hosokawa Micron Co., Ltd.) Rotary rotor type air classifier with classification rotor; Elbow Jet (manufactured by Nittetsu Mining Co.) etc. Coanda effect using Coanda effect (Elbow jet type classifier); Dry type Examples include air classifiers that use mesh openings such as Sieve High Volta (Toyo Hitec) and Dry Sieve Blower Shifter (Yugrop). Among these, a high-precision air classifier, a rotary rotor type air classifier, and an air classifier using the Coanda effect are preferable because they can remove coarse particles efficiently! /.

[0026] The high-accuracy air classifier is a dispersion zone formed by moving parts (movable members) and air flowing into the classification zone to generate a high-speed swirling air current, and centrifugal force is applied to the particles supplied into the apparatus. In addition, the air is exhausted from the classification zone by a suction blower so as to resist the centrifugal force applied to the particles, and the coarse and fine particles are classified from the particles by the balance between the centrifugal force and the drag. Device. Rotating rotor type airflow classification device is equipped with a freely rotating cylinder (classification rotor) and an intake port that takes air into the device from outside the device. Centrifugal force due to eddy currents is applied to the particles supplied inside, while the drag force of the centrifugal force is This is a device that takes in air to classify the coarse powder and fine powder from the particles based on the balance between centrifugal force and drag force. An air classifier that uses the Coanda effect is a Coanda effect that uses a Coanda effect in which a jet flows along a wall when a wall is placed only on one side. Depending on the properties (coarse powder, fine powder (target product), fine powder, etc.), a part of the ejector ejected into the device together with the feed air), a Coanda block that guides the jet (including particles) into the classification chamber Separating classification edge is provided at any position. The jet (including particles) ejected from a part of the ejector tends to flow along the Coanda block. At this time, the inertial force acting on the particles (there is a difference in the inertial force acting on the fine particles and coarse particles, and the coarse particles try to fly further), Particles are classified.

[0027] Among the airflow classifiers, an airflow classifier (elbow, one-jet type classifier) using the Counder effect is preferred. When this elbow jet classifier is used, it is preferable to raise the feed air to the maximum recommended air pressure in order to improve the classification accuracy. In general, it is recommended that the feed air be set to 0!;! ~ LOkgf;! ~ 5kgf from the viewpoint of improving the accuracy of force classification. In general, if the feed air is increased too much, the flying distance of coarse particles increases, and there is a high possibility that coarse particles that bounce off the front wall will be mixed into the fine powder. However, the fine particles according to the present invention are obtained through a wet classification process and then a dry classification process, as will be described later, and since the coarse particles are removed to some extent by the wet classification process, they rebound. There is no mixing of coarse particles into fine powder. Therefore, classification accuracy can be improved by raising the feed air.

[0028] It is also preferable to use a slim edge as the classification edge in order to improve classification accuracy. As described above, the classification edge is used to isolate particles according to their properties, and one end (particle entry side) has a wedge-shaped shape that becomes thicker toward the other end. is doing. Further, the bottom cross section (one end having a thickness in the wedge shape) is substantially rectangular and has a specific width. Note that the width of the classification edge is usually designed to be approximately equal to the width of the flow path of the jet flow containing particles. Here, the slim edge has a shorter distance between the wedge-shaped slopes than the standard edge that is usually used. About half of the standard edge). The slim edge is usually used to prevent particles from accumulating at the tip of the edge and reducing classification accuracy when processing highly charged particles. The reason why the classification accuracy is improved by using the slim edge is considered to be that the disturbance of the air flow hardly occurs in addition to the purpose of the slim edge (suppressing the reduction of the classification accuracy due to the accumulation of particles).

[0029] The fine powder particles subjected to the dry classification are wet-classified with a fine particle dispersion having a solid content concentration of 0.5 to 50% by mass and a B-type viscosity of 0.5 to 20 mPa's, and then dried and pulverized. What is obtained is preferable. The solid content concentration of the fine particle dispersion is preferably from 0.5 to 20% by mass. The B-type viscosity is preferably from 0.5 to; lOmPa's.

[0030] When the solid content concentration of the fine particle dispersion solution supplied to the wet classifier is high or the viscosity is high, it takes a long time for classification, or the load on the mesh increases and the mesh opening increases. May increase the classification accuracy. In addition, when the solid content concentration is less than 0.5% by mass, the classification takes a long time.

[0031] Further, it is preferable that the particles to be subjected to wet classification have a small content of coarse particles larger than a particle size twice the average particle size. Specifically, it is preferable that the content force of coarse particles larger than a particle size twice as large as the average particle size is 1 million or less per 0.5 g. More preferably, it is 500,000 pieces / 0.5 g, more preferably 200,000 pieces / 0.5 g or less.

[0032] The fine particle dispersion may be prepared by dispersing fine particles prepared in advance in a dispersion medium (water, organic solvent, etc.). In the case where the fine particles have an organic polymer or organic-inorganic composite material strength described later. The reaction solution after the polymerization reaction may be used as it is. You can also use the fine particle dispersion obtained by the wet process.

[0033] Apparatuses that can be used for wet classification of the above-mentioned fine particle dispersion are not particularly limited! /, But include a filtration apparatus using a finoleta sieve, a centrifugal force, and a liquid cyclone apparatus using an inertial force. Can be mentioned. Specific wet classifiers include cartridge filters (for example, manufactured by Loki Tano Co., Ltd., Nippon Ball Co., Ltd.), and liquid cyclones (for example, manufactured by Rasa Industrial Co., Ltd., manufactured by Industry) that perform classification using centrifugal force. Can be mentioned.

[0034] A plurality of cartridge filters may be used in combination. For example, a final filter that satisfies the required filtration accuracy for the purpose of reducing running costs by extending the service life. A combination of a filter and a prefilter used to extend the life of the final filter may be used. However, the final filter selection criteria is preferably a type that can remove 50% by mass or more of particles twice the average particle size. For example, an SLP type cartridge filter manufactured by Loki Techno Co., Ltd. is preferable as a final filter because it has a filter medium thickness that is a feature of a depth filter and a wide filter area that is a feature of a pleated filter. The pre-filter selection criterion is preferably a type that can filter 50% by mass or more of particles more than 3 times the average particle size.

The liquid cyclone device is a device that uses a liquid as a medium and classifies particles dispersed in the liquid by centrifugal force. For example, in the case of a device having a cylindrical (or conical) portion, fine particle dispersion is supplied from the tangential direction of the device cylindrical portion, and coarse particles are centrifuged while the fine particle dispersion descends the cylindrical portion as a swirling flow. It is moved in the radial direction by the action of force, collides with the inner wall of the cylinder, drops along the inner wall to the lower part of the device, and is recovered from the lower part of the device. On the other hand, the fine particles move upward along the upward swirling flow generated near the center, so that the fine particles are recovered from the upper part of the device.

[0036] The particles after wet classification are preferably dried and pulverized! /. The dry and pulverized conditions are the physical properties of the fine powder particles described above (moisture content 0.05 to 2 mass%, true specific gravity;! To 1.25 g / ml, bulk specific gravity 0.;! To lg / ml, The particle size is not particularly limited as long as it can satisfy 1 to 50 111).

[0037] The fine particles of the present invention are obtained by dry-classifying fine powder particles having predetermined physical properties, and may be combined with other classification means as needed, in particular, fine powder particles. It is recommended that the wet classification process described above be used for the adjustment from the viewpoint of reducing the content of coarse particles and fine particles to a low level. That is, a preferred process for obtaining the fine particles of the present invention is a process of subjecting a fine particle dispersion having predetermined physical properties to wet classification, drying and pulverizing the particles after wet classification, and further subjecting to dry classification. Be By passing through such a process, the fine particles of the present invention in which the number of coarse particles having a particle size of twice or more the average particle size is 1000 or more / 0.5 g or less can be obtained more efficiently.

[0038] Next, the structure and manufacturing method of the fine particles according to the present invention will be described.

[0039] The form of the fine particles according to the present invention is not particularly limited, and an organic polymer, an inorganic material, an organic It may be any of the inorganic composite materials. Examples of the organic polymer include linear polymers such as polystyrene, polymethyl methacrylate, polyethylene, polypropylene, polyethylene terephthalate, polybutylene terephthalate, polysulfone, polycarbonate, and polyamide; dibulebenzene, hexatriene, dibule ether, Divinylsulfone, diallyl carbinol, alkylene diatalylate, oligo or polyalkylene glycol diatalylate, oligo or polyalkylene glycol dimetatalylate, alkylene tritalylate, alkylene tetraatalylate, alkylene trimetatalylate, both Reticulated polymers obtained by polymerizing terminal acrylic-modified polybutadiene oligomers alone or with other polymerizable monomers; amino compounds (for example, benzogua Min, melamine there have can be mentioned organic polymer comprising Amino resin obtained by polycondensation reaction of urea, etc.) and formaldehyde.

[0040] Examples of the organic-inorganic inorganic composite material include (A) fine particles in which inorganic fine particles such as metal oxides such as silica, alumina, and titania, metal nitrides, metal sulfides, and metal carbides are dispersed and contained in an organic resin. And (B) fine particles formed by a metalloxane chain (molecular chain containing a “metal-oxygen-metal” bond) such as (organo) polysiloxane and polytitanoxane and organic molecules at the molecular level, methyltrimethoxysilane, etc. Polysiloxanes and polymerizable groups made from silicon fine particles such as polymethylsilsesquioxane obtained by hydrolysis and condensation reaction of organoalkoxysilanes, and (C) silicon compounds having hydrolyzable silyl groups. An organic polymer skeleton obtained by reacting with a polymerizable monomer having a butyl group (for example, a bur group, a (meth) ataryloyl group, etc.) Organic non-machine quality composite material comprising a polysiloxane skeleton.

[0041] Examples of the inorganic material include glass, silica, and alumina.

[0042] Among the above examples, fine particles made of an organic polymer or an organic-inorganic inorganic composite material are preferable because the characteristics of the fine particles can be designed relatively freely, and particles having a sharp particle size distribution can be easily obtained. . Further, among the fine particles made of an organic polymer, the organic polymer made of an amino resin, and the organic polymer particles obtained by the seed polymerization method (the ratio of the crosslinkable monomer to the total amount of the polymerizable monomer is 20% by mass or more, more Preferably 3 (C) is particularly preferable among fine particles made of an organic-inorganic composite material in which particles of 0% by mass or more, more preferably 50% by mass or more are preferred. Further, these particles are hardened or cross-linked during the synthesis process, and are hardly dissolved or swollen by an organic solvent. Therefore, when used in a coating resin composition for forming a light diffusing layer and an antiglare layer, which will be described later, even if used simultaneously with an organic solvent or the like, the particles are unlikely to change in quality or change in particle diameter. This is preferable because the effect of reducing the large particles within the above range can be sufficiently obtained.

[0043] These particles are preferably subjected to a wet classification process in the state of a particle suspension obtained at the time of synthesis of each particle! That is, a suspension with a small content of coarse particles more than twice the average particle size (for example, less than 1 million particles / 0.5 g) is easily obtained. Particularly preferred are fine particles having an organic-inorganic composite material strength and organic polymer fine particles having an amino resin strength, which can be obtained by a preferable production method described below!

[0044] The particle preferably has a particle diameter variation coefficient (based on a particle size distribution calculated on a volume basis) of 20% or less. More preferably, it is 10% or less. The smaller the variation coefficient of the particle size, the smaller the variation in the particle size.If the above range is satisfied, the amount of coarse particles contained in the fine particles after the wet classification and dry classification processes is reduced. Since it is easy to reduce, it is preferable. Here, the variation coefficient of the particle diameter is a value calculated from the following formula.

[0045] country

Coefficient of variation of particle size (%) = (σ) χ 1 0 0

Here, σ is the standard deviation of the particle diameter, and X is the average particle diameter.

In the present invention, the average particle size and the standard deviation of the particle size are measured using the above-described precision particle size distribution measuring apparatus (for example, “Multisizer II” manufactured by Beckman Coulter, Inc.), and the volume is measured. Calculated by reference.

Here, the structure and manufacturing method of the fine particles (amino resin) composed of the organic polymer and the fine particles (organic (C)) composed of the organic-inorganic composite material will be described.

First, a method for producing amino resins (amino resin crosslinked particles), which are fine particles made of the organic polymer, will be described. [0049] Examples of the production method of the amino resin crosslinked particles include a first production method and a second production method described below. According to these first and second production methods, since the particle diameter can be controlled in the fine particle synthesis stage, the production of coarse particles can be somewhat suppressed. Therefore, by subjecting the amino resin crosslinked particles obtained by the production method to the above-described process for obtaining the fine particles according to the present invention, it is easier to reduce the content of particles that deviate from the preferred range of the particle size. Therefore, it is preferable. First, the first manufacturing method will be described.

[0050] First manufacturing method

The first production method of the crosslinked amino resin particles (hereinafter sometimes simply referred to as “first production method”) is a resinization method in which an amino compound and formaldehyde are reacted to obtain an amino resin precursor. A step of emulsifying the amino resin precursor obtained in the resinification step in an aqueous medium to obtain an emulsion of the amino resin precursor, and a catalyst in the emulsion obtained in the emulsification step. In addition, it includes a curing step of performing a curing reaction of the emulsified amino resin precursor to obtain amino resin crosslinked particles.

[0051] The resinification step is a step of reacting an amino compound with formaldehyde to produce an amino resin precursor that is an initial condensation reaction product. Water is used as a solvent for reacting the amino compound with formaldehyde. Specific methods for carrying out this resination step include a method in which an amino compound is added to formaldehyde in an aqueous solution (formalin) and reacted, or trioxane or paraformaldehyde is added to water to formaldehyde in water. Preferred examples include a method in which an amino compound is added to an aqueous solution prepared so as to cause the reaction. In particular, the former method is more preferable in terms of economy because it requires a preparation tank for an aqueous formaldehyde solution and it is easy to obtain raw materials. In addition, regardless of which method is employed, the resinification step is preferably performed with stirring by a known stirring device or the like.

[0052] The amino compound used as a starting material in the resinification step is not particularly limited. For example, benzoguanamine (2,4 diamine-6 phenyl sym. —Triazine), cyclohexanecarboguanamine And cyclohexenecarboguanamine and melamine. Of these, amino compounds having a triazine ring are more preferred. Yes. In particular, since benzoguanamine has a benzene ring and two reactive groups, when benzoguanamine is included as an amino compound, the resulting amino resin crosslinked particles are flexible (hardness), stain resistant, and heat resistant. It is particularly preferable because of its excellent properties, solvent resistance and chemical resistance. The above amino compounds may be used alone or in combination of two or more.

[0053] The total proportion of the amino compounds (benzoguanamine, cyclohexanecarboguanamine, cyclohexenecarboguanamine, and melamine) in the total amount of the amino compounds to be used should be 40% by mass or more. Is more preferably 60% by mass or more, still more preferably 80% by mass or more, and most preferably 100% by mass. When the content of the amino compound is 40% by mass or more, the resulting amino resin crosslinked particles are excellent in heat resistance and solvent resistance.

[0054] The molar ratio (amino compound (mole) / formaldehyde (mole)) of amino compound and formaldehyde to be reacted in the resination process is 1/3 · 5 to 1/1 · 5. 1 / 3.5 ~; 1/1 · 8 is more preferable than force S, and 1/3 · 2 ~; 1/2 is more preferable. If the above molar ratio is less than 1/3. 5, there is a risk of increasing the amount of unreacted formaldehyde, and if it exceeds 1 / 1.5, there may be an increase in the amount of unreacted amino compound. .

[0055] Note that the concentration of the amino compound and formaldehyde at the time of preparation of the resinification step is desirably higher as long as the reaction is not hindered. Specifically, the viscosity at the temperature range of 95-98 ° C of the reaction solution containing the amino resin precursor is the reaction product, 2X10- ^² ~5. 5X10- ² Pa range's (20~55cP) It is preferable to adjust the concentration within a controllable range. More preferably, in the emulsification step described later, the reaction solution is added to an aqueous solution of an emulsifier or an emulsifier or an emulsifier is added to the reaction solution so that the concentration of the amino resin precursor in the emulsion is within a range of 30 to 60% by mass. Any concentration may be used as long as an aqueous solution of the emulsifier can be added.

[0056] Accordingly, the viscosity within the temperature range of 95 to 9 8 ° C of the reaction solution containing the Amino resin precursor obtained in resinification ^{^{process, 2X10- 2 ~5. 5X10- 2 Pa}} 's (20~55cP) it mosquito preferably, more preferably ^{^{2 · 5X10- 2 ~5. 5X10- 2}} Pa's (25~55cP), even more favorable Mashiku ^{^{3.0X10- 2 ~5. 5X10- 2 Pa's}} (30~55cP) is there. Method for measuring the viscosity and Therefore, a method using a viscometer that can grasp the progress of the reaction immediately (in real time) and accurately determine the end point of the reaction is optimal. As such a viscometer, a vibration viscometer (manufactured by MIVIITS Japan, product name: MIVI6001) can be used. This viscometer has a vibrating part that vibrates at all times. By immersing the vibrating part in the reaction liquid, the viscosity of the reaction liquid increases and a load is applied to the vibrating part. The load is immediately converted into viscosity and displayed.

[0057] By reacting an amino compound and formaldehyde in water (in an aqueous medium), an amino resin precursor which is a so-called initial condensate can be obtained. The reaction temperature is preferably within a temperature range of 95 to 98 ° C. so that the progress of the reaction can be immediately grasped and the end point of the reaction can be accurately determined. The reaction of the amino compound and formaldehyde, when the viscosity of the reaction solution becomes within a range of ^{2 X 10- 2 ~5. 5 X} 10- 2 Pa 's, such as cooling the reaction mixture What is necessary is just to complete | finish by operating. Thereby, a reaction liquid containing an amino resin precursor is obtained. The reaction time is not particularly limited.

[0058] The amino resin precursor obtained in the resinification step is a molar ratio of the structural unit derived from the amino compound and the structural unit derived from formaldehyde constituting the amino resin precursor (the structural unit derived from the amino compound). (Mol) / formaldehyde-derived structural unit (mol)) is 1 / 3.5 ~; 1/1 · 5 force S, preferably 1/3 · 5 ~; 1/1 · 8 force More preferably, it is more preferably 1/3. If the molar ratio is within the above range, the particle size distribution is narrow! / And the ability to obtain particles can be obtained.

[0059] The amino resin precursor is usually acetone, dioxane, methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, ethyl acetate, butyl acetate, methineless cellosolve, ethyl acetate solve, methyl ethyl ketone, toluene, xylene, etc. Forces that are soluble in other organic solvents are substantially insoluble in water.

[0060] In the first production method, the particle diameter of the finally obtained amino resin crosslinked particles is reduced by reducing the viscosity of the reaction solution in the resinification step of preparing the reaction solution containing the amino resin precursor. can do. While also force 'is less than s, or 5. 5 X 10- ² Pa' viscosity of the reaction solution 2 X 10- ² Pa when exceeding s eventually particle diameter was approximately Soroitsu ( In some cases, it is difficult to obtain crosslinked amino resin particles having a narrow particle size distribution. That is, When the viscosity of the reaction solution is less than ² × 10−2 Pa ′ s (20 cP), the stability of the emulsion obtained in the emulsification step described later becomes poor. For this reason, when the amino resin precursor is cured in the curing step, the resulting amino resin crosslinked particles may be enlarged or the particles may be aggregated, and the particle diameter of the amino resin crosslinked particles can be controlled. Therefore, there is a possibility that amino resin crosslinked particles having a wide particle size distribution may be obtained. Also, if the stability of the emulsion is poor, the particle size (average particle size) of the amino resin cross-linked particles may change each time it is manufactured (each batch), which may cause variations in the product. There is also. On the other hand, if the viscosity of the reaction solution is greater than ^{5. 5 X 10- 2 Pa 's} (55cP), too large a load applied to the high-speed stirrer or the like to be used in the emulsion step described later, since the shearing force decreases, The reaction solution may not be sufficiently stirred (emulsified). For this reason, it is difficult to control the particle diameter of the finally obtained amino resin crosslinked particles, which may result in amino resin crosslinked particles having a wide particle size distribution. Therefore, it is preferable to adjust the reaction solution in the above viscosity range in advance in the resinification step.

[0061] The emulsification step is a step of preparing an emulsion of the amino resin precursor by emulsifying the amino resin precursor obtained in the resinification step. For emulsification of the amino resin precursor, for example, it is preferable to use an emulsifier that can form a protective colloid, and in particular, it is preferable to use an emulsifier made of a water-soluble polymer that can form a protective colloid! / ,.

[0062] Examples of the emulsifier include polybulal alcohol, carboxymethylcellulose, sodium alginate, polyacrylic acid, water-soluble polyacrylic acid salt, and polybulurpyrrolidone. These emulsifiers may be used in the form of an aqueous solution in which the entire amount is dissolved in water, or a part of the emulsifier is used in the form of an aqueous solution and the rest is used as it is (for example, powder, granule, liquid, etc.). May be. Among the emulsifiers exemplified above, polybulal alcohol is more preferable in consideration of the stability of the emulsion, interaction with the catalyst, and the like. The polybulal alcohol may be a completely saponified product or a partially saponified product. Further, the degree of polymerization of polybulal alcohol is not particularly limited.

[0063] The amount of the emulsifier used is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the amino resin precursor obtained in the resinification step;! To 5 parts by mass Is more preferable. If the amount used is outside the above range, the stability of the emulsion may be poor. Also, As the amount of emulsifier used relative to the mino resin precursor increases, the particle size of the resulting particles tends to decrease.

[0064] In the emulsification step, for example, the reaction obtained in the resinification step so that the concentration of the amino resin precursor (that is, the solid content concentration) is in the range of 30 to 60% by mass in the aqueous solution of the emulsifier. After adding the liquid, it is preferable to make the emulsion within a temperature range of 50 to 100 ° C. More preferably, the temperature is 60 to 100 ° C, and still more preferably 70 to 95 ° C. The concentration of the aqueous solution of the emulsifier is not particularly limited as long as the concentration of the amino resin precursor can be adjusted within the above range. If the concentration of the amino resin precursor is less than 30% by mass, the productivity of the amino resin crosslinked particles may be lowered. If the concentration exceeds 60% by mass, the resulting amino resin crosslinked particles may be enlarged or the particles may aggregate. Control of the particle diameter of the crosslinked amino resin particles may be difficult, and the particle size distribution of the resulting crosslinked amino resin particles may be widened.

[0065] In the emulsification step, it is preferable to use an apparatus (an apparatus having a high shearing force) that can more strongly stir the amino resin precursor and the aqueous solution of the emulsifier as the stirring means! Specific examples of the stirrer include, for example, a so-called high-speed stirrer, homomixer, TK homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), high-speed disperser, Ebara Milezaichi (manufactured by Ebara Corporation), Izumi Food Machinery Co., Ltd.), static mixer (manufactured by Noritake Company Limited), etc.

[0066] In the emulsification step, it is preferable to promote emulsification until the amino resin precursor obtained in the resinification step has a predetermined particle size. It should be noted that the predetermined particle diameter may be appropriately set so that finally the amino resin crosslinked particles having a desired particle diameter can be obtained. Specifically, the emulsification is carried out so that the average particle size of the emulsified amino resin precursor becomes 0.; Is preferably 0.5 to 20 mm 111, and more preferably 1 to 5 mm. By emulsifying the amino resin precursor so as to be in the above particle size range as described above, the particle size of the amino resin crosslinked particles can be controlled within a desired range.

[0067] In the first production method, the milk obtained after the above emulsification step is, if necessary, to more reliably prevent the finally obtained amino resin crosslinked particles from agglomerating firmly. Inorganic particles can be added to the suspension. Specific examples of the inorganic particles include silica fine particles, zirconium fine particles, aluminum powder, alumina sol, and serie sol. Silica fine particles are more preferable because they are easily available. . The specific surface area of the inorganic particles is preferably from it preferably tool is ^{^{10~400m 2 / g 20~350m 2 / g}} , even more preferably 30~300m ² / g. The particle size of the inorganic particles is more preferably 0.2 in or less, more preferably 0. or less, and still more preferably 0.05 05 or less. If the specific surface area and the particle diameter are within the above ranges, it is possible to exhibit a more excellent effect in preventing the finally obtained amino resin crosslinked particles from being strongly aggregated.

[0068] The method of adding the inorganic particles to the emulsion is not particularly limited. Specifically, for example, the method of adding the inorganic particles as they are (particulate), or the inorganic particles to water. The method of adding in the state of the disperse | distributed liquid etc. is mentioned. The amount of inorganic particles added to the emulsion is preferably from! To 30 parts by mass, more preferably from 2 to 28 parts by mass, based on 100 parts by mass of the amino resin precursor contained in the emulsion. Even more preferably, it is 3 to 25 parts by mass. If the amount is less than 1 part by mass, it may not be possible to sufficiently prevent the finally obtained amino resin crosslinked particles from agglomerating firmly. If the amount exceeds 30 parts by mass, an aggregate of only inorganic particles may be present. May occur. Moreover, as a stirring method at the time of adding inorganic particles, the method using the above-mentioned apparatus having a high shearing force is preferable in that the inorganic particles are firmly fixed to the amino resin particles.

[0069] In the curing step, a catalyst (specifically a curing catalyst) is added to the emulsion prepared in the emulsification step, and the emulsified amino resin precursor is cured (the amino resin precursor is hardened in an emulsion state). ) To produce amino resin crosslinked particles (specifically, suspension of amino resin crosslinked particles).

[0070] As the catalyst (curing catalyst), an acid catalyst is suitable. Acid catalysts include mineral acids such as hydrochloric acid, sulfuric acid and phosphoric acid; ammonium salts of these mineral acids; sulfamic acids; sulfonic acids such as benzenesulfonic acid, paratoluenesulfonic acid and dodecylbenzenesulfonic acid; phthalic acid, benzoic acid, Organic acids such as acetic acid, propionic acid, salicylic acid and the like can be used. Of the acid catalysts illustrated above, mineral acids are preferred in terms of cure speed. Furthermore, they are corrosive to equipment and use mineral acids. In terms of safety during use, sulfuric acid is more preferable. In addition, when sulfuric acid is used as the catalyst, for example, compared with the case where dodecylbenzenesulfonic acid is used, the finally obtained amino resin cross-linked particles are less likely to be discolored and are preferable because of high solvent resistance. These acid catalysts may be used alone or in combination of two or more.

[0071] The amount of the catalyst used is preferably 0.;! To 5 parts by mass with respect to 100 parts by mass of the amino resin precursor in the emulsion obtained by the emulsification step. Is 0.3 to 4.5 parts by mass, and still more preferably 0.5 to 4.0 parts by mass. If the amount of the catalyst used exceeds 5 parts by mass, the emulsion state may be destroyed and the particles may agglomerate. If the amount is less than 0.1 parts by mass, the reaction may take a long time or be cured. May become insufficient. Similarly, the amount of the catalyst used is preferably 0.002 mol or more, more preferably 0.005 mol or more, and still more preferably based on 1 mol of the amino compound used as the raw material compound. 0. 01 -0. 1 mole. If the amount of the catalyst used is less than 0.002 mol with respect to 1 mol of the amino compound, the reaction may take a long time or the curing may be insufficient.

[0072] In the curing reaction in the curing step, the reaction solution (emulsion) is preferably at 15 (room temperature) to 80 ° C, more preferably 20 to 70 ° C, still more preferably 30 to 60 ° C, and at least After holding for 1 hour, it is preferably carried out at a temperature in the range of 60 to 150 ° C, more preferably 60 to 130 ° C, more preferably 60 to 100 ° C under normal or elevated pressure. preferable. If the reaction temperature of the curing reaction is less than 1S 60 ° C, curing may not proceed sufficiently, and the solvent resistance and heat resistance of the resulting amino resin crosslinked particles may be reduced. On the other hand, when the reaction temperature exceeds 150 ° C, a strong pressure reactor is required, which is not economical. The end point of the curing reaction may be judged by sampling or visual observation. Further, the reaction time of the curing reaction is not particularly limited.

[0073] A known stirring device may be used as the stirring means that is preferably performed under stirring in the curing step. In the curing step, the average particle diameter of the crosslinked amino resin particles obtained by curing the emulsion of the amino resin precursor in the emulsion state is preferably 0.;! To 20 m, more preferably 0. 5 to 20 111, even more preferably;! To 5 m.

[0074] The first production method may include a coloring step of adding an aqueous solution obtained by dissolving a dye in water to a suspension of an emulsion of an amino resin precursor and an amino resin crosslinked particle. [0075] In the first production method, a neutralization step of neutralizing the suspension containing the amino resin crosslinked particles obtained by the curing step may be provided. The neutralization step is preferably performed when an acid catalyst such as sulfuric acid is used as the curing catalyst in the curing step. By performing the neutralization step, the acid catalyst can be removed (specifically, the acid catalyst can be neutralized). For example, in the heating step described later, the amino acid when the amino resin crosslinked particles are heated is used. It is possible to suppress the discoloration of the resin crosslinked particles (for example, discoloration to yellow).

“Neutralization” as used in the neutralization step means that the pH of the suspension containing the amino resin crosslinked particles is 5 or more, and more preferably 5-9. If the pH of the suspension is less than 5, since the acid catalyst remains, the amino resin bridge particles may be discolored in the heating step described later. By adjusting the pH of the suspension within the above range by neutralization, amino resin bridge particles having high hardness, excellent solvent resistance and heat resistance, and no discoloration can be obtained. As a neutralizing agent that can be used in the neutralization step, for example, an alkaline substance is suitable. Examples of the alkaline substance include sodium carbonate, sodium hydroxide, potassium hydroxide, and ammonia S. Among them, an aqueous sodium hydroxide solution that sodium hydroxide is preferable is preferable because it is easy to handle. Used. These can be used alone or in combination of two or more.

[0077] In the first production method, a separation step of taking out the amino resin crosslinked particles from the suspension of the amino resin crosslinked particles obtained after the curing step or after the neutralization step may be provided.

[0078] Examples of a method (separation method) for taking out the amino resin crosslinked particles from the suspension include a filtration method and a method using a separator such as a centrifuge, but the method is particularly limited. Any of the conventionally known separation methods can be used.

[0079] The amino resin crosslinked particles taken out from the suspension may be washed with water or the like, if necessary.

[0080] In the first production method, it is preferable to perform a heating step of heating the amino resin crosslinked particles taken out through the separation step at a temperature of 130 to 190 ° C. By performing the heating process, moisture adhering to the amino resin crosslinked particles and remaining free (unreacted) formaldehyde can be removed, and condensation (crosslinking) in the amino resin crosslinked particles can be further reduced. Power to promote S If the heating temperature is lower than 130 ° C, the amino resin cross-links Condensation (crosslinking) within the particles cannot be sufficiently promoted, and the hardness, solvent resistance and heat resistance of the crosslinked amino resin particles may not be improved. The resulting amino resin crosslinked particles may be discolored. Even when the neutralization step described above is performed, the effect when the heating temperature is outside the above temperature range is the same. From the viewpoint of improving various properties (hardness, solvent resistance, heat resistance, and discoloration resistance) of the resulting crosslinked amino resin particles, the heating temperature of the crosslinked amino resin particles is within the above range after performing the neutralization step. Is preferable.

[0081] The heating method in the heating step is not particularly limited, and a generally known heating method may be used. The heating step may be completed when, for example, the moisture content of the amino resin crosslinked particles reaches 3% by mass or less, preferably 2% by mass or less. Further, the heating time is not particularly limited.

[0082] The amino resin crosslinked particles obtained by the first production method are separated from the aqueous medium at the time of emulsification, dried and pulverized, and then the obtained pulverized product is dispersed in a solvent and suspended. This can be supplied to wet and dry classification processes. In addition, the suspension after the curing step (including any suspension until the separation step such as the suspension obtained through the neutralization step after the curing step) may be subjected to wet classification. This is a preferred embodiment of the method of the present invention. The suspension after the wet classification is dried and pulverized after the above-described separation step and heating step as necessary, to obtain fine powder particles having a moisture content of 0.05 to 2% by mass. It is preferable to use it for the classification process.

[0083] Next, a second method for producing an amino resin crosslinked particle will be described.

[0084] Second manufacturing method

The second production method of the crosslinked amino resin particles (hereinafter sometimes simply referred to as “second production method”) refers to an amino resin precursor obtained by reacting an amino compound with formaldehyde. The amino resin precursor is granulated and precipitated in the aqueous medium by mixing with a surfactant in an aqueous medium and adding a catalyst to the mixed solution, and then the amino resin crosslinked particles are added to the aqueous medium. This is a method of separating the force and drying, and then crushing the resulting dried product.

[0085] In the second manufacturing method, as in the first manufacturing method, the resin conversion step is adopted and the resin conversion process is performed. In this process, the amino compound precursor and formaldehyde are reacted to form an amino resin precursor. In the second production method, the amino resin precursor obtained in the resinification step is mixed with a surfactant in an aqueous medium. A curing process to obtain amino resin crosslinked particles by adding a catalyst to the mixed solution containing the amino resin precursor and the surfactant to form particles by precipitation and precipitation of the amino resin precursor. It differs from the first manufacturing method in adopting it.

[0086] In the second production method, it is easy to prepare crosslinked amino acid particles having a small particle diameter by initiating curing of the amino resin precursor in an aqueous solution state (for example, average particle diameter). 0 · 1 ~ 50 ^ 111) ₀

[0087] It is preferable that the type and composition ratio of the amino compound used in the second production method are appropriately set so as to satisfy the degree of water miscibility described later. For example, it is more preferable to use an amino compound that can react with formalin to produce a water-soluble amino resin precursor.

[0088] The amino resin precursor obtained in the resinification step is preferably water-soluble. The surfactant used in the second production method is used for imparting water affinity to the aqueous medium of the amino resin precursor, and the surfactant is used for the first production. The emulsifier used in the method is not included.

[0089] In the present invention, the water affinity is 15% by mass% of the amount of water added to the initial condensate until water is dropped to the amino resin precursor that is the initial condensate to cause white turbidity (hereinafter referred to as "%"). This is called water miscibility.) The higher the value, the higher the water affinity. Note that the water miscibility of the amino resin precursor suitable for the second production method is 100% or more. In the case of an amino resin precursor having a water miscibility of less than 100%, no matter how it is dispersed in an aqueous liquid containing a surfactant, only a non-uniform suspension having a relatively large particle size is formed. The spherical fine particles obtained in this way are unlikely to have a uniform particle size (wide particle size distribution).

[0090] In the mixing step, the amino resin precursor obtained in the resinification step is mixed with a surfactant in an aqueous medium by stirring or the like to prepare a mixed solution.

Examples of the surfactant include ayu surfactant and cationic surfactant. Any surfactant such as an agent, a nonionic surfactant, and an amphoteric surfactant can be used, but an anionic surfactant, a nonionic surfactant, or a mixture thereof is particularly preferable.

[0091] Examples of the anionic surfactant include alkali metal alkyl sulfates such as sodium dodecyl sulfate and potassium dodecyl sulfate; ammonium alkyl sulfates such as ammonium dodecyl san sulfate; sodium dodecyl polyglycol ether sulfate; sodium Sulfolicinoates; Alkyl sulfonates such as alkali metal salts of sulfonated paraffins, ammonium salts of sulfonated paraffins; Fatty acids such as sodium laurate, triethanolamine oleate, triethanolamine abiate, etc. Salts: Alkyl aryl sulfonic acid salts such as sodium dodecylbenzenesulfonate, alkali metal sulfate of alkali phenolic ethylene; Lunaphthalene sulfonate; naphthalene sulfonate formalin condensate; dialkyl sulfosuccinate; polyoxyethylene alkyl sulfate salt; polyoxyethylene alkyl aryl sulfate salt can be used. Polyoxyethylene alkyl aryl ester; Sorbitan fatty acid ester; Polyoxyethylene sorbitan fatty acid ester; Fatty acid monodalides such as monolaurate of glycerol; Polyoxyethylene oxypropylene copolymer; Ethylene oxide A condensation product with an aliphatic amine, amide or acid can be used.

[0092] The amount of the surfactant used is preferably in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the amino resin precursor obtained in the resinification step. If the amount is less than 01 parts by mass, a stable suspension of the amino resin bridge particles may not be obtained. If the amount exceeds 10 parts by mass, unnecessary foaming may occur in the suspension, or the final suspension may be lost. It may adversely affect the physical properties of the resulting amino resin crosslinked particles.

[0093] In the mixing step, for example, in the aqueous solution of the surfactant, the concentration of the amino resin precursor (that is, the solid content concentration) is obtained in the above resination step so as to be in the range of 3 to 25% by mass. It is preferable to mix after adding the reaction solution. In this case, the concentration of the aqueous surfactant solution is not particularly limited, and the concentration of the amino resin precursor can be adjusted within the above range. Any concentration can be used. If the concentration of the amino resin precursor is less than 3% by mass, the productivity of the amino resin crosslinked particles may be reduced. If the concentration exceeds 25% by mass, the resulting amino resin crosslinked particles may be enlarged or particles may be produced. There is a possibility that they may aggregate with each other, and the particle diameter of the amino resin crosslinked particles cannot be controlled, so that there is a possibility that the particles have a wide particle size distribution and amino resin crosslinked particles.

[0094] As a stirring method in the mixing step, a general stirring method may be employed. For example, a stirring method using stirring blades such as a disk turbine, a fan turbine, a Faudler type, a propeller type, and a multistage blade is used. Etc. are preferred.

[0095] In the second production method, in order to prevent the finally obtained amino resin crosslinked particles from agglomerating firmly, if necessary, inorganic particles are added to the mixed liquid obtained after the mixing step. It may be added. Regarding the inorganic particles and the addition method thereof, the description in the first production method described above can be similarly applied.

[0096] In the curing and granulating step, a catalyst (specifically a curing catalyst) is added to the mixed solution prepared in the above mixing step to carry out the curing reaction and particle formation of the amino resin precursor. Specifically, a suspension of amino resin crosslinked particles) is produced.

[0097] As the catalyst (curing catalyst), an acid catalyst is suitable. As the acid catalyst, the same force S as exemplified in the first production method is preferably used, and in the second production method, alkylbenzenesulfonic acid having an alkyl group having 10 to 18 carbon atoms is used. It is preferable to use it. Alkylbenzenesulfonic acid having an alkyl group having 10 to 18 carbon atoms exhibits a unique surface activity in the aqueous liquid of the amino resin precursor as the initial condensate, and forms a stable suspension of the cured resin. Generate. Specific examples include decyl benzene sulfonic acid, dodecyl benzene sulfonic acid, tetradecyl benzene sulfonic acid, hexadecyl benzene sulfonic acid, and octadecyl benzene sulfonic acid. These can be used alone or in combination of two or more.

[0098] The amount of the catalyst used is preferably 0.;! To 20 parts by mass with respect to 100 parts by mass of the amino resin precursor in the mixed solution obtained by the mixing step. 0.5 to 10 parts by mass, even more preferably;! To 10 parts by mass. When the amount of the catalyst used is less than the above range, it takes a long time for condensation and curing, and the stable crosslinking of the amino resin crosslinked particles. There is a possibility that a suspension cannot be obtained, and can only be obtained in a state containing a large amount of particles that are finally agglomerated and coarsened. On the other hand, if the amount exceeds the above range, the catalyst such as alkylbenzene sulfonic acid is distributed more than necessary in the amino resin crosslinked particles in the generated suspension, and as a result, the amino resin crosslinked particles are dispersed. If the particles are agglomerated and condensed between the particles during condensation curing, fusion is likely to occur, and finally an amino resin crosslinked particle having a uniform particle size may not be obtained!

[0099] Similarly, the amount of the catalyst used is preferably 0.005 mol or more, more preferably 0.002 mol or more with respect to 1 mol of the amino compound used as the raw material compound. More preferably, it is 0.005-0.05 mol. If the amount of the catalyst used is less than 0.0005 mol with respect to 1 mol of the amino compound, the reaction may take a long time or the curing may be insufficient.

[0100] Curing · The curing reaction and particle formation in the particle formation process are carried out by adding the above catalyst to the mixture of the amino resin precursor and stirring the solution from a low temperature of 0 ° C to a high temperature of 100 ° C or higher under pressure. It is sufficient to keep at an appropriate temperature. The method for adding the catalyst is not particularly limited and can be appropriately selected. The end point of the curing reaction may be judged by sampling or visual observation. Moreover, the reaction time of the curing reaction is not particularly limited. The curing reaction is generally a force that can be completed by raising the temperature to 90 ° C or higher and holding it for a certain period of time. It is sufficient if the amino resin bridge particles in the suspension are cured to such an extent that they do not swell with methanol or acetone.

[0101] It is preferable that the curing and particle formation step be performed under stirring by a generally known stirring device or the like. The average particle size of the preferred amino resin crosslinked particles is the same as that of the average particle size of the amino resin crosslinked particles in the curing step of the first production method.

[0102] The second production method may include a neutralization step of neutralizing the suspension containing the amino resin crosslinked particles obtained by the curing step. For details such as the pH range and the type of neutralizing agent in the neutralization step, the explanation in the first production method can be applied in the same way.

[0103] In the second production method, there is provided a separation step of taking out the amino resin crosslinked particles from the suspension of the amino resin crosslinked particles obtained after the curing and particle forming step or after the neutralization step. You may choose. In the second production method, the separation of the amino resin crosslinked particles from the suspension means that the amino resin crosslinked particles obtained by curing are separated and removed from the aqueous medium in the mixing step. is there. As a method (separation method) for taking out the amino resin crosslinked particles from the suspension, a method similar to the first production method can be applied.

[0104] In the second production method, it is preferable to perform a heating step in which the amino resin crosslinked particles taken out through the separation step are heated at a temperature of 130 to 190 ° C. As conditions for the heating step, the same conditions as those for the heating step of the first manufacturing method can be applied.

[0105] The amino resin crosslinked particles obtained by the second production method are separated from the aqueous medium at the time of the mixing step or the curing and granulating step, dried and pulverized. It is preferable to mix with a solvent to form a suspension, which is subjected to wet classification, separation and drying, and then dry classification. It is preferable to supply the suspension after the curing and granulating step or the suspension after the neutralization step / water washing step to wet and dry classification. After wet classification, it is preferable to separate the particles, and if necessary, dry and pulverize them through a heating step to form fine powder particles having a water content of 0.05 to 2% by mass, and then dry classification.

[0106] Next, the structure and manufacturing method of the fine particles (the above (C)) made of an organic-inorganic composite material will be described. Known polymerization methods such as emulsion polymerization, suspension polymerization, seed polymerization, and sol-gel polymerization are applicable without particular limitation to the method for polymerizing fine particles of the organic-inorganic composite material.

[0107] As described above, fine particles (hereinafter referred to as composite particles) that are organic-inorganic composite material force are particles including an organic polymer skeleton as an organic part and a polysiloxane skeleton as an inorganic part. is there. The composite particle has an organic carbon atom in which a chemical atom in the polysiloxane skeleton is directly chemically bonded to at least one carbon atom in the organic polymer skeleton (chemical bond). Type). As a specific form, the polysiloxane skeleton and the organic polymer skeleton form a three-dimensional network structure by bonding the carbon atom in the polysiloxane skeleton and the carbon atom in the organic polymer skeleton. And I like the form!

[0108] The organic polymer skeleton may have a side chain, a branched structure, or a bridge structure. Molecular weight and composition of organic polymer forming the skeleton The structure and the presence / absence of a functional group are not particularly limited. Examples of the organic polymer include (meth) acrylic resins, bully polymers such as polystyrene and polyolefin, polyamide such as nylon, polyimide, polyester, polyether, polyurethane, and polyurea.

, Polycarbonate, phenolic resin, melamine resin, and urea resin

[0109] The form of the organic polymer skeleton is represented by the following formula (1) because the hardness of the composite particles can be appropriately controlled:

[0110] [Chemical 1]

A polymer having a main chain composed of repeating units represented by the formula (so-called bull polymers) is preferable.

[0111] The polysiloxane skeleton has the following formula (2):

[0112] [Chemical 2]

Is defined as a compound in which a network having a network structure is formed by continuous chemical bonding of siloxane units represented by The amount of SiO constituting the polysiloxane skeleton is preferably from 0.;! To 25% by mass, more preferably from 1 to 10%, based on the weight of the composite particles. If the amount of SiO 2 in the polysiloxane skeleton is in the above range, the hardness of the composite particles can be easily controlled. Further, if it is less than 0.1% by mass, the flexibility and elasticity of the particles are lowered, and there is a possibility that the inside of the particles may be broken when external stress is applied to the resin composition. If it exceeds 1, the adhesion between the particles and the resin is lowered, and the particles in the resin composition may easily fall off. The amount of SiO constituting the polysiloxane skeleton is a mass percentage obtained by measuring the mass before and after firing the particles at a temperature of 800 ° C. or higher in an oxidizing atmosphere such as air. [0113] In the composite particles, the ratio of the number of carbon atoms to the number of carbon atoms (surface atom number ratio (C / Si)) obtained by photoelectron spectroscopy is 1.0 to 1; it is OX 10 ⁴ are preferable from the viewpoint of excellent adhesion with the resin when used in blending a resin. If the above surface atom number ratio (C / Si) is less than 1.0, the adhesiveness with the resin may be lowered.

0 ⁴ if it exceeds, the reduced flexibility and elasticity of the particles, there are problems will be caused a fear such that the external stress to the resin composition to destroy the particle interior when Cor pressure.

[0114] The composite particles may be arbitrarily adjusted by appropriately changing the ratio of the polysiloxane skeleton portion or the organic polymer skeleton portion with respect to the hardness, fracture strength, and the like! Can do.

[0115] The polysiloxane skeleton in the composite particles is preferably obtained by a hydrolytic condensation reaction of a silicon compound having a hydrolyzable group.

[0116] The hydrolyzable silicon compound is not particularly limited. For example, the following general formula (3):

R 'mSiX (3)

(Where R ′ represents at least one group selected from the group consisting of an alkyl group, an aryl group, an aralkyl group and an unsaturated aliphatic group which may have a substituent, and X is a hydroxyl group. , Represents at least one group selected from the group consisting of an alkoxy group and an acyloxy group, and m is an integer of 0 to 3.

[0117] The silicon compound represented by the general formula (3) is not particularly limited. For example, those having m = 0 include tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, and tetrabutoxysilane. Tetrafunctional silanes such as m = l include methyltrimethyoxysilane, methinoretriethoxysilane, ethinoretrimethoxysilane, ethinoretriethoxysilane, hexyltrimethoxysilane, decyltrimethoxysilane, phenyl Trimethoxysilane, mono (3,4-epoxycyclohexenole) ethinoretrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, butyltrimethoxysilane, 3- (meth) attaryloxypropyltrimethoxysilane, 3, 3, 3—Trifunctional such as trifluoropropyltrimethoxysilane Silane; m = 2 Difunctional methoxy silane, dimethyl retoxy silane, diacetoxy dimethyl silane, diphenyl silane diol and other bifunctional silanes; m = 3 are trimethyl methoxy silane, trimethyl ethoxy silane, trimethyl silanol, etc. And monofunctional silanes.

[0118] Among these, in the above general formula (3), m is a silane compound having a structure of 1, X being a methoxy group or an ethoxy group, and a refractive index of 1.30 to 1.60. Is preferable because organic-inorganic composite particles having a refractive index suitable for optical applications can be obtained. Specifically, methyltrimethoxysilane, phenyltrimethoxysilane, 3- (meth) atalyloxypropyltrimethyoxysilane, β- (3,4-epoxycyclohexyleno) ethinoretrimethoxysilane, 3, 3, Three

[0119] The derivative of the silicon compound represented by the general formula (3) is not particularly limited. For example, a part of X is substituted with a group capable of forming a chelate compound such as a carboxyl group and a β-dicarbonyl group. And low condensates obtained by partially hydrolyzing the silane compound.

[0120] The hydrolyzable silicon compound may be used alone or in a suitable combination of two or more. In the above general formula (3), when only the silane compound and its derivative with m = 3 are used as raw materials, composite particles cannot be obtained.

[0121] In the case where the composite particle has a polysiloxane skeleton force S and an organic key atom in which a key atom is directly bonded to at least one carbon atom in the organic polymer skeleton, As the hydrolyzable silicon compound, it is necessary to use one having an organic group containing a polymerizable reactive group capable of forming an organic polymer skeleton. Examples of the reactive group include a radical polymerizable group, Examples thereof include an epoxy group, a hydroxyl group, and an amino group.

[0122] Examples of the organic group containing the radical polymerizable group include the following general formulas (4), (5) and (6):

CH = C (-R ^a ) -COOR ^b- (4)

(Here, R ^a represents a hydrogen atom or a methyl group, R ^b represents an optionally substituted carbon number;! To 20 divalent organic group.) CH = C (— R ^c ) — (5)

(Here, represents a hydrogen atom or a methyl group.)

CH = C (-R ^d ) -R ^e- (6)

(Here, R ^d represents a hydrogen atom or a methyl group, represents a carbon number which may have a substituent;! To 20 represents a divalent organic group.)

And the like, and the like.

[0123] Examples of the radical-polymerizable group-containing organic group of the general formula (4) include an attaoxy group and a methacryloxy group. Examples of the silicon compound of the general formula (3) having the organic group include For example, Ί-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ attaryloxypropyl trimethoxysilane, γ-acryloxypropyltriethoxysilane, _γ -methacryloxypropyltriacetoxysilane , Γ-methacryloxyethoxypropyltrimethoxysilane (or _Ί -trimethoxysilyl pill / 3-methacryloxychetyl ether), γ-methacryloxypropylmethyoxypropylmethyldimethoxysilane, etc. . These may be used alone or in combination of two or more.

[0124] Examples of the radical-polymerizable group-containing organic group of the general formula (5) include a bur group and an isopropenyl group. The silicon compound of the general formula (3) having the organic group and Examples thereof include butyltrimethoxysilane, butyltriethoxysilane, butyltrimethoxysilane, vinylino methinoresin methoxysilane, vinino methinolegetoxy silane, and vinino methino resin acetyloxy silane. These may be used alone or in combination of two or more. Examples of the radical-polymerizable group-containing organic group represented by the general formula (1) include 1 alkenyl group or butylphenyl group, isoalkenyl group or isopropenyl phenyl group, and the general formula (3) having the organic group. Examples of the silicon compound include 1-hexenyltrimethoxysilane, 1-hexenyltriethoxysilane, 1-octenyltrimethoxysilane, 1-decenyltrimethoxysilane, and _γ -trimethoxysilinolepropylbutyl ether. Ω-trimethoxysilylundecanoic acid butyl ester, ρ-tri Silane, 1-hexenylmethyljetoxysilane and the like can be mentioned. These can be used alone or in combination of two or more.

[0125] Examples of the silicon compound having an organic group containing an epoxy group include 3 glycyglycidoxypropynoletriethoxysilane, β- (3,4 epoxycyclohexenole) ethynoletrimethoxysilane, and the like. Can be mentioned. These may be used alone or in combination of two or more. Examples of the silicon compound having an organic group containing a hydroxyl group include 3-hydroxypropyltrimethoxysilane. These may be used alone or in combination of two or more.

[0126] Examples of the silicon compound having an organic group containing an amino group include Ν-β (aminoethyl) y-aminopropylmethyldimethoxysilane, Ν-β (aminoethyl) _γ- aminopropyltrimethoxysilane, Ν-β (aminoethyl) _γ- aminopropyltriethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminopropyltriethoxysilane, 一 phenyl γ-aminopropyltrimethoxysilane, etc. be able to. These can be used alone or in combination of two or more.

[0127] The organic polymer skeleton contained in the composite particle is, for example, 1) The silicon compound can form an organic polymer skeleton such as a radical polymerizable group or an epoxy group together with a hydrolyzable group. In the case of having an organic group containing a polymerizable reactive group, 1 1) a method of polymerizing after the hydrolysis condensation reaction of the silicon compound, or 1 2) a polysiloxane skeleton obtained by the hydrolysis condensation reaction of the silicon compound is used. It is also possible to absorb a polymerizable monomer having a polymerizable reactive group such as a radically polymerizable monomer, a monomer having an epoxy group, a monomer having a hydroxyl group, and a monomer having an amino group, and then polymerizing the particles. can get. 2) When there is no organic group containing a polymerizable reactive group capable of forming an organic polymer skeleton such as the above-mentioned silicon compound strength S, radical polymerizable group, epoxy group, hydroxyl group, amino group, etc. Particles having a polysiloxane skeleton obtained by hydrolytic condensation reaction (seed particles made of polysiloxane particles, hereinafter also referred to as polysiloxane particles) have radical polymerizable monomers, monomers having epoxy groups, and hydroxyl groups. Having a polymerizable reactive group such as a monomer and a monomer having an amino group It can also be obtained by causing a polymerization reaction after absorbing a polymerizable monomer.

[0128] The composite particles as described above have a) an organic silicon atom in which a polysiloxane skeleton is directly chemically bonded to at least one carbon atom in the organic polymer skeleton in the molecule. / !, or even a form (chemical bond type)! /, And b) such a form (IPN type) that does not have an organic key atom in the molecule. Although not limited, for example, when an organic polymer skeleton is obtained together with a polysiloxane skeleton as in 1) above, composite particles having the form of a) can be obtained, as in 2) above. In this case, composite particles having the form b) are obtained. Further, when the organic polymer skeleton is obtained together with the polysiloxane skeleton as in the above 12), composite particles having a form having both the above a) and) forms are obtained.

[0129] In the above methods 1 2) and 2), the radical polymerizable monomer that can be absorbed by the particles having a polysiloxane skeleton is preferably a monomer component that essentially requires a radical polymerizable butyl monomer. Examples of the radical polymerizable butyl monomer include, but are not particularly limited to, as long as it is a compound containing at least one ethylenically unsaturated group in the molecule, depending on the desired physical properties of the composite particles. Can be selected appropriately. These can be used alone or in combination of two or more.

[0130] For example, a hydrophobic radically polymerizable bur monomer is preferable because a stable emulsion in which the monomer component is emulsified and dispersed can be generated when the monomer component is absorbed into particles having a polysiloxane skeleton. In addition, if a crosslinkable monomer, which may be a crosslinkable monomer, is used as the radical polymerizable bull monomer, the mechanical properties of the resulting composite particles can be easily adjusted, and the solvent resistance of the composite fine particles can be adjusted. It can also improve the performance. Specific examples include ethylene glycol dimetatalylate, trimethylol-propyl pantrimethylolaretalylate, 1,6 xanthinoregiophthalate, divininolevene and the like. These may be used alone or in combination of two or more.

[0131] Preferred examples of the method for producing the composite particles include a production method including a hydrolysis and condensation step, which will be described later, and a polymerization step. Further, if necessary, an absorption step for absorbing the polymerizable monomer may be included after the hydrolysis and condensation step and before the polymerization step (in the case of the above 1 2) and 2)). Note that the strength of the silicon compound used in the hydrolysis and condensation processes If it does not have an element that constitutes the siloxane structure together with an element that constitutes the organic polymer skeleton (in the case of 2), the absorption step is essential, and the organic polymer skeleton is used in the polymerization step that follows this absorption step. Is formed.

[0132] The hydrolysis and condensation step is a step in which the above-described silicon compound is hydrolyzed in a solvent containing water to undergo condensation polymerization. By this step, particles having a polysiloxane skeleton (polysiloxane particles) can be obtained. Hydrolysis and polycondensation can employ any method such as batch, split or continuous. In the hydrolysis and condensation polymerization, a basic catalyst such as ammonia, urea, ethanolamine, tetramethylammonium hydroxide, alkali metal hydroxide, alkaline earth metal hydroxide or the like is used as a catalyst. Use with power S

[0133] The solvent containing water may contain an organic solvent in addition to water and the catalyst. Examples of organic solvents include alcohols such as methanol, ethanol, isopropanol, n butanol, isobutanol, sec butanol, t-butanol, pentanol, ethylene glycol, propylene glycol, and 1,4 butanediol; acetone, methyl ethyl ketone, and the like. Examples thereof include ketones; esters such as ethyl acetate; (cyclo) paraffins such as isooctane and cyclohexane; aromatic hydrocarbons such as benzene and toluene. These can be used alone or in combination of two or more.

[0134] In the hydrolysis and condensation processes, anionic, cationic, and nonionic surfactants, and polymer dispersants such as polybulal alcohol and polybulylpyrrolidone can also be used in combination. These can be used alone or in combination of two or more.

[0135] Hydrolysis and condensation are performed by mixing the silicon compound as a raw material with a solvent containing a catalyst, water, and an organic solvent, and then at a temperature of 0 to 100 ° C, preferably 0 to 70 ° C, for 30 minutes. Can be done by stirring for ~ 100 hours. In addition, particles may be produced by hydrolysis and condensation reactions to a desired degree, and then used as seed particles to add silicon compounds to the reaction system and grow the seed particles. Les.

[0136] The polysiloxane particles preferably have a weight average molecular weight of 250 to 10,000, more preferably 250 to 5,000. If the weight average molecular weight is within the above range, polymerization that remains without being absorbed in the system in which the absorption rate of the polymerizable monomer in the absorption process is high. The generation of coarse particles derived from functional monomers is suppressed, and as a result, the composite particles (used for dry classification) have a coarse particle content that is at least twice the average particle size or a low content of fine particles. Body particles are obtained. Further, by subjecting the composite particles to wet classification and dry classification processes, the content of coarse particles is extremely low and particles can be obtained in high yield and yield.

[0137] As described above, the absorption process may be an essential process or may be an optional process depending on the silicon compound to be used. The absorption step is not particularly limited as long as it proceeds in the presence of a polymerizable monomer in the presence of polysiloxane particles. Therefore, the polymerizable monomer may be added to the solvent in which the polysiloxane particles are dispersed, or the polysiloxane particles may be added to the solvent containing the polymerizable monomer. In particular, as in the former case, it is preferable to add a polymerizable monomer in a solvent in which polysiloxane particles are dispersed in advance.Furthermore, the polysiloxane particles obtained in the hydrolysis and condensation step are reacted with a reaction solution (polyester). A method of adding a polymerizable monomer to the reaction liquid without taking it out from the siloxane particle dispersion liquid is preferable because the process is not complicated and the productivity is excellent.

[0138] In the absorption step, the polymerizable monomer is absorbed in the structure of the polysiloxane particle, but each of the polysiloxane particle and the polymerizable monomer is absorbed so that the absorption of the polymerizable monomer proceeds promptly. The concentration, mixing ratio of the above polysiloxane and polymerizable monomer, mixing treatment method and means, temperature and time during mixing, treatment method and means after mixing, etc. are set and performed under the conditions. preferable. The necessity of these conditions may be taken into consideration as appropriate depending on the type of polysiloxane particles and polymerizable monomers used. These conditions may be applied alone or in combination of two or more.

[0139] The addition amount of the polymerizable monomer in the absorption step is preferably 0.01 times to 100 times the mass of the silicon compound used as the raw material for the polysiloxane particles. . More preferably, it is 0.5 to 50 times, still more preferably 0.5 to 30 times, and particularly preferably 1 to 15 times. When the addition amount is less than the above range, the amount of the polymerizable monomer of the polysiloxane particles absorbed is reduced, and it is difficult to obtain the mechanical properties of the composite particles to be produced. However, it tends to be difficult to completely absorb the added polymerizable monomer in the polysiloxane particles. Since the polymer remains, aggregation between particles may occur in the subsequent polymerization step, or coarse particles derived from unabsorbed polymerizable monomers may be easily generated.

[0140] The timing of addition of the polymerizable monomer is not particularly limited in the absorption step, and the polymerizable monomer may be added all at once or may be added in several times. You may feed at any speed. In addition, when adding the polymerizable monomer, it may be added only with the polymerizable monomer, or a solution of the polymerizable monomer may be added. It is preferable to add to the particles because absorption into the polysiloxane particles is more efficiently performed.

[0141] The emulsifier is not particularly limited! /, But, for example, a cationic surfactant, a cationic surfactant, a nonionic surfactant, an amphoteric surfactant, a polymer surfactant, And polymerizable surfactants having one or more polymerizable carbon-carbon unsaturated bonds. Among these, an anionic surfactant and a nonionic surfactant are preferable because they can stabilize the dispersion state of polysiloxane particles, polysiloxane particles having absorbed a polymerizable monomer, and polymer fine particles. These emulsifiers may be used alone or in combination of two or more.

[0142] The amount of the emulsifier used is not particularly limited. Specifically, it is preferably 0.01 to 10% by mass based on the total mass of the polymerizable monomer, more preferably 0.0 5 to 8% by mass, more preferably 1 to 5% by mass. When the amount of the emulsifier used is less than 0.01% by mass, an emulsion dispersion of a stable polymerizable monomer may not be obtained. When the amount exceeds 10% by mass, emulsion polymerization or the like occurs as a side reaction. There is a risk of it. Regarding the above emulsification dispersion, it is usually preferable that the polymerizable monomer is emulsified in water using a homomixer, an ultrasonic homogenizer, or the like together with an emulsifier.

[0143] When the polymerizable monomer is emulsified and dispersed with an emulsifier, it is preferable to use 0.3 to 10 times as much water or a water-soluble organic solvent as the mass of the polymerizable monomer. Examples of the water-soluble organic solvent include alcohols such as methanol, ethanol, isopropanol, η-butanol, isobutanol, sec-butanol, t-butanol, pentanonole, ethylene glycolanol, propylene glycol, and 1,4-butanediol. Ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate and the like. [0144] The absorption step is preferably performed in the temperature range of 0 to 60 ° C with stirring for 5 minutes to 720 minutes. These conditions may be set as appropriate depending on the types of polysiloxane particles and polymerizable monomers to be used. These conditions may be used alone or in combination of two or more.

[0145] In the absorption process, for determining whether the monomer component is absorbed by the polysiloxane particles, for example, before adding the monomer component and after completion of the absorption step, the particles are observed with a microscope, and the particles are absorbed by the absorption of the monomer component. It can be easily judged by confirming that the diameter has increased.

[0146] The polymerization step is a step of obtaining particles having an organic polymer skeleton by polymerizing a polymerizable reactive group. Specifically, when a silicon compound having a polymerizable reactive group-containing organic group is used, it is a step of polymerizing a polymerizable reactive group of the organic group to form an organic polymer skeleton, and an absorption step is performed. If this is the case, the force that is the process of forming an organic polymer skeleton by polymerizing a polymerizable monomer having a polymerizable reactive group that has been absorbed corresponds to both of the processes, and the process forms an organic polymer skeleton by either reaction. obtain.

[0147] The polymerization reaction may be performed in the middle of the hydrolysis-condensation step or the absorption step, and may be performed after either or both of the steps, but is not particularly limited. Start later (after the absorption process if the absorption process is performed).

[0148] The polymerization reaction is not particularly limited, and for example, any of a method using a radical polymerization initiator, a method of irradiating with ultraviolet rays or radiation, a method of applying heat, etc. can be adopted. The radical polymerization initiator is not particularly limited, and examples thereof include persulfates such as potassium persulfate, hydrogen peroxide, peracetic acid, benzoyl peroxide, lauroyl peroxide, orthochloroperoxybenzoyl peroxide, and orthomethoxyperoxide. Benzoyl, 3, 5, 5-trimethylhexanoyl peroxide, t-butylperoxy-2-ethylhexanoate, di-t-butyl peroxide, benzoyl peroxide, 1,1-bis (t-butylperoxy) -3, Peroxide-based initiators such as 3,5-trimethylcyclohexane, t-ptylnoide mouth peroxide, etc .; azobisisobutyronitrile, azobiscyclohexacarboxynitryl, azobis (2,4-dimethylvalero) Nitrile), 2'-azobisisobutyronitrile, 2, 2'-azobis (2-amidinopropane) 'dihydrochloride, 4, 4'-azobis (4- Cyanpentanoic acid), 2, 2'-azobis- (2-methyl) Preferred examples include azo compounds such as butyronitrile), 2,2'-azobisisobutyronitrile, 2,2'-azobis (2,4-dimethylvaleronitryl), and the like. These radical polymerization initiators may be used alone or in combination of two or more! /.

[0149] The amount of the radical polymerization initiator used is 0.

More preferably, the content is 001% by mass to 20% by mass, more preferably 0.01% by mass to 10% by mass, and still more preferably 0.1% by mass to 5% by mass. When the amount of the radical polymerization initiator used is less than 0.001% by mass, the polymerization degree of the polymerizable monomer may not increase. The method of charging the radical polymerization initiator into the solvent is not particularly limited. First, the whole amount is charged (before the start of the reaction) (a mode in which the radical polymerization initiator is emulsified and dispersed together with the polymerizable monomer, the polymerizable monomer is A mode in which a radical polymerization initiator is charged after absorption); a method in which a part is charged first, and the rest is continuously fed, a pulse is added intermittently, or a combination of these methods The conventionally known method can also adopt the force!

[0150] The reaction temperature for the radical polymerization is preferably 40 to 100 ° C, more preferably 50 to 80 ° C. If the reaction temperature is too low, the degree of polymerization will not increase sufficiently, and the mechanical properties of the polymer fine particles will tend to be difficult to obtain, whereas if the reaction temperature is too high, aggregation between particles will occur during the polymerization. Tends to occur. The reaction time for the radical polymerization may be appropriately changed according to the type of polymerization initiator used, but usually 5 to 600 minutes is preferable, and 10 to 300 minutes is more preferable. When the reaction time is too short, the degree of polymerization may not be sufficiently increased, and when the reaction time is too long, aggregation tends to occur between particles.

[0151] In the present invention, after the polymerization step, the obtained preparation liquid containing the polymer fine particles is used as it is or after the organic solvent is distilled and replaced with a dispersion medium containing water and / or alcohol, The polymer fine particles produced may be isolated and dried, dispersed in water and / or an organic solvent, and then supplied to the wet classification step.

[0152] Since the fine particles of the present invention have a reduced content of coarse particles and fine particles and a narrow particle size distribution, the light diffusion sheet or light guide plate used in optical applications such as LCDs, Alternatively, it is useful as an additive such as a light diffusing agent or an antiblocking agent contained in an optical resin used for PDP, EL display, touch panel and the like. Of course, it is also suitably used as an antiblocking agent for various films other than these optical uses.

[0153] The resin composition according to the present invention is a resin composition containing the fine particles of the present invention and a transparent binder resin. As described above, the fine particles of the present invention are suitably used for optical applications because the content of not only coarse particles but also fine particles is suppressed to an extremely low level.

[0154] The content of the fine particles in the resin composition may be appropriately determined according to the use and desired optical properties, but in the case of use for optical uses, the binder resin composition is contained in 100 parts by mass. On the other hand, the amount is preferably 1 part by mass or more and 300 parts by mass or less. More preferably, it is 2 parts by mass or more, further preferably 5 parts by mass or more, more preferably 200 parts by mass or less, and further preferably 150 parts by mass or less. If the content of the fine particles is too large, the strength of the optical component may be reduced. If the content is too small, it is difficult to obtain the expected effects (such as light diffusibility) by adding fine particles! / There is.

[0155] The transparent binder resin contained in the resin composition of the present invention is not particularly limited, and any of those used as a binder resin in this field can be used. For example, (I) When the member formed using the resin composition of the present invention is formed into a desired shape such as a plate shape or a sheet shape of the resin composition of the present invention itself (that is, In case of using binder resin as base resin for plate-like or sheet-like molded products), transparent resin includes polyester resin such as polyethylene terephthalate and polyethylene naphthalate, acrylic resin, polystyrene resin, polycarbonate resin, polyethersal Polyolefin resins such as phon resin, polyurethane resin, polysulfone resin, polyether resin, polymethylpentene resin, polyether ketone resin, (meth) acrylonitrile resin, polypropylene resin, norbornene resin, amorphous polyolefin resin, polyamide Resin, polyimide resin, and triaceti Cellulose resins.

[0156] Also, (II) a member formed by laminating (coating, laminating, etc.) the resin composition of the present invention on a previously prepared substrate surface such as a plate or sheet. In this case, the same transparent binder resin as the above binder resin can be used. Examples thereof include acrylic resin, polypropylene resin, polybutyl alcohol resin, polyvinyl acetate resin, polystyrene resin, polychlorinated bur resin, silicon resin, polyurethane resin, and polyester resin.

[0157] The resin composition of the present invention does not impair the effects of the present invention in addition to the fine particles and the transparent binder resin! /, And if necessary, contains other components as required! /, Moyo! / ヽ. Examples of other components include a curing agent, a crosslinking agent, various additives and stabilizers, a flame retardant, an antioxidant, and an ultraviolet absorber in order to enhance physical properties such as light resistance and UV resistance. These may use only 1 type and may use 2 or more types together.

[0158] Since the molded product obtained from the resin composition of the present invention is a molded product in which the fine particles of the present invention are dispersed and fixed in the binder resin, it has excellent optical properties such as light diffusibility and light transmittance. It comprises. Therefore, the resin composition of the present invention is suitably used as a raw material for constituent members of various optical products. From the viewpoint of effectively utilizing the excellent light diffusibility and light transmittance derived from the fine particles of the present invention described above, it is installed on the front surface of various image display devices so that it can be used for outside light and indoors. An anti-glare anti-glare film that prevents the reflection of lighting equipment and makes the image display clear, and a light diffusion film and light that uniformly diffuses the light from the light source to the image display surface in the image display device. It is suitably used for optical members such as a diffusion plate.

[0159] The shape of the optical member is not limited to a film shape (sheet shape) or a plate shape, and may be formed into a desired shape such as a column, a cone, or a sphere. From the viewpoint of securing an excellent light diffusion effect and antiglare effect (antiglare effect by suppressing and diffusing regular reflection of light), the surface of the optical member is derived from the fine particles of the present invention described above. It is preferable that irregularities to be formed are formed.

[0160] For example, when the optical member is a film-like molded body (hereinafter referred to as "optical film") such as a light diffusing film or an antireflection antiglare film, the form thereof is planar. And a configuration (optical functional layer) in which the light diffusing particles are fixed by a transparent binder resin. For example, a transparent binder resin itself constituting the ω resin composition is used as a base resin such as a plate or sheet, and is formed into a plate or film (such as a light diffusing plate) (i) prepared in advance Plate or sheet A layer composed of the above resin composition is laminated (coating, laminating) on a part of or the entire surface of the base material, and is integrated (surface uneven film such as light diffusion film and antiglare film, light diffusion plate) Etc.). In any of the above forms (i) and (ii), the particles S are dispersed and fixed in the transparent binder resin.

[0161] Note that the above-mentioned "having a planar portion" generally means that the optical member is substantially flat with a certain area spread, such as a plate shape, a sheet shape, or a film shape. However, in the present invention, the present invention is not limited to such an embodiment, and the main component is not limited to such an aspect (including the case where fine irregularities are formed on the surface). If not, it is sufficient that at least a part of the shape has a substantially flat surface portion.

[0162] As a method for producing the optical member of the above form (i), the resin composition of the present invention is extruded into a sheet, plate, and film by extrusion while melting and kneading with a known extruder. The method of doing is mentioned. At this time, if necessary, in order to enhance physical properties such as light resistance and UV resistance, various additives, additives such as a stabilizer and a flame retardant may be added to the resin composition. In order to obtain a molded article having uniform optical properties, the resin composition is preferably mixed and dispersed in advance with the fine particles of the present invention in a transparent binder resin. Similarly, the additive may be mixed with the resin composition.

[0163] Examples of the method for obtaining the optical member of the form (ii) include a method of laminating a layer made of the resin composition of the present invention on a previously prepared base material surface. The lamination method is not particularly limited, and preferred examples include a coating method and a casting method. As a coating method, a coating composition containing the resin composition may be applied to a substrate. The resin composition of the present invention can be used as a coating composition as it is. The above resin composition is mixed with water or an organic solvent (for example, alcohol solvent such as methanol, ethanol, isopropanol, ethylene glycol, propylene, etc.). It is preferable to use a coating composition prepared by dispersing and dissolving in a ketone solvent such as glycol, an ester solvent such as ethyl acetate, and an aromatic hydrocarbon such as toluene and xylene. The substrate is not particularly limited. 1S For example, polyolefin resin film, polyester resin film, polycarbonate Conventionally known colorless and transparent resin films such as nate resin films are preferably used. Specific coating methods include known laminating methods such as reverse roll coating, gravure coating, die coating, comma coating, and spray coating.

[0164] After coating, if necessary, the solvent contained in the coating film is dried, and then the coating film is solidified to form a resin composition layer. From the viewpoint of ensuring heat resistance and weather resistance, the layer made of the resin composition is preferably cured or crosslinked with the binder resin contained in the resin composition.

[0165] The thickness of the layer made of the resin composition (or coating composition) of the present invention formed by the above-described method is not particularly limited, but in the case of the light diffusion film, the layer made of the resin composition (light The thickness of the diffusion layer is 30 11 m or less. In the case of an anti-glare film, the layer made of the resin composition (anti-glare layer) is 20 am or less, and the thickness of the light diffusion plate is 2000 μm or less. Preferably there is. Conventionally, when the thickness is thin, it has been difficult to develop sufficient light diffusibility and light transmission, and if the fine particles or resin composition of the present invention is used, the thickness is extremely small. Excellent light diffusibility and light transmittance can be exhibited. In addition, the value of the said light-diffusion film and anti-glare film film thickness represents the thickness of the layer (namely, light-diffusion layer, anti-glare layer) containing the resin composition laminated | stacked on the base material. The thickness of is not included.

[0166] The fine particles of the present invention have an extremely low content of coarse particles, and in addition to a sharp particle size distribution, the coating composition also undergoes alterations such as swelling. Since the particles are difficult and chemically stable, uniform and fine irregularities can be formed on the above-described optical member (light diffusion film, antiglare film, light diffusion plate, etc.). Therefore, optical members such as a light diffusing film, an antiglare film, and a light diffusing plate obtained by using the fine particles of the present invention have local glare from coarse particles, and appearance defects. It is hard to produce the optical foreign material which becomes. Further, since the optical characteristics can be adjusted by controlling the average particle diameter of the fine particles of the present invention, it is suitably used for optical applications.

Example

[0167] Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to the following examples as well as the present invention. It is also possible to carry out with addition, and they are all included in the technical scope of the present invention. It is. Unless otherwise specified, mass parts may be expressed as “parts” and mass% as “%”.

[0168] Production of fine particles

Production Example 1 (Polysiloxane fine particles)

Put a mixed solution of 280 parts of ion-exchanged water, 5 parts of 25% ammonia water and 120 parts of methanol into a reaction kettle equipped with a cooling device, thermometer and dropping port. -Add 40 parts of methacryloxypropyltrimethoxysilane and heat and condense -methacryloxypropyltrimethoxysilane for 2 hours at 30 ° C to prepare polysiloxane fine particle suspension. did. The polysiloxane particles obtained at this time had a weight average molecular weight of 1800 (corresponding to about a 7-mer of the silicon compound used).

[0169] Separately, in a reaction vessel 2 different from the above, 400 parts of styrene, 3 parts of 2,2'-azobis (2,4-dimethylvaleronitrile) (manufactured by Wako Pure Chemical Industries, Ltd., V-65), Anionic surfactant (LA-10, manufactured by Daiichi Kogyo Co., Ltd.) 1. Emulsions were prepared by emulsifying and dispersing 5 parts and 400 parts of ion-exchanged water with a homomixer at room temperature (25 ° C) for 15 minutes. (Monomer solution).

[0170] Two hours after the start of the preparation of the polysiloxane particle suspension (two hours after the addition of γ-methacryloxypropyltrimethoxysilane), the emulsion was added from the dropping port of the reaction vessel 1. After stirring for 1 hour and confirming that the polysiloxane particles have absorbed the monomer components, 3500 parts of ion-exchanged water is added thereto, and the reaction solution is heated to 65 ° C under a nitrogen atmosphere. The mixture was held at 65 ± 2 ° C. for 2 hours, and a radical polymerization reaction was performed to obtain a polymer particle (organic-inorganic composite particle) dispersion. The average particle size of the polymer particles dispersed in the dispersion is 10.1 am, the B-type viscosity of the dispersion (B-type viscometer, manufactured by Tokyo Keiki Co., Ltd.) is 3.8 mPa's, and the solid content concentration is 10 It was mass%.

[0171] Production Examples 2 to 7 (polysiloxane particles)

A polymer particle dispersion was prepared in the same manner as in Production Example 1, except that the polysiloxane particle raw material, the radical polymerizable monomer species, and the amount used were changed as shown in Table 1. The amounts of ion-exchanged water, methanol, and surfactant used for the preparation of the suspension of the polysiloxane particles and emulsion were appropriately adjusted according to the conditions of each production example.

[Measurement of average particle size and amount of coarse particles of polymer particles]

The polymer particle dispersion obtained in the above production example was subjected to solid-liquid separation and dried polymer particles. Disperse 5 g in ion-exchanged water lOOg to prepare a polymer particle dispersion, and use a precision particle size distribution measuring device (product name `` Multisizer II '', manufactured by Beckman Coulter Co., Ltd.) The particle diameter was measured, and the average particle diameter was calculated on a volume basis.

[0173] Measurement of the amount of coarse particles (coarse particles having a particle size of at least twice the average particle size) contained in the polymer particle dispersion was performed as follows.

[0174] Polymer particle dispersion in which 0.5 g of dried polymer particles is dispersed in methanol lOOg

(Viscosity: 3 mPa _'S, solid concentration:. 0 5 wt%) was adjusted to a mesh having 1.75 to 2 times the mesh of average particle size (nickel, Tokyo Process Service Co., Ltd.), Filtration was performed under reduced pressure using a suction filtration device equipped with a Buchner funnel on the filter bell. Next, the particles remaining on the mesh were observed with a scanning electron microscope (SEM, “S_3500N”, manufactured by Hitachi, accelerating voltage: 25 kV), and the number of coarse particles more than twice the average particle diameter was visually observed. I counted. The observation was performed at a magnification of 200 times and the entire visual field was observed. The results are shown in Table 1 as “> average diameter X 2”.

[0175] Further, in the case of the amount of coarse particles having an average particle size of 2.5 times or more, except that a mesh having an opening of 2.25-2.5 times the average particle size is used, The procedure was the same as described above. The results are shown in Table 1 as “> Average diameter X 2.5”.

[0176] [SiO content]

Polymer particles lg were calcined at 800 ° C. (in the atmosphere) in a calcining furnace, and the ratio of SiO to the mass of the polymer particles used was calculated with the generated ash as SiO.

[0177] [Solid concentration]

The solid content concentration of the polymer particles was determined by drying 0.5 g of the polymer particle dispersion solution at 120 ° CX for 20 minutes (in vacuum), and measuring the ratio of the remaining solid content to the mass of the polymer particle dispersion. The partial concentration was used.

Solid content concentration (%) = [residual solid content mass / polymer particle dispersion mass] X 100

[0178] [bulk specific gravity]

It measured with the powder tester (made by Hosokawa Micron Corporation).

[0179] [Moisture content]

Karl Fischer moisture meter (manufactured by Hiranuma Sangyo Co., Ltd.) using 0.5 g of pulverized particles as a measurement sample It measured using.

[0180] [weight average molecular weight]

The weight average molecular weight was measured using gel permeation chromatography (GPC, “HLC-812GPC”, manufactured by Tosohichi Corporation) under the following measurement conditions. The measurement sample was prepared by diluting the sample with tetrahydrofuran (THF) so that the solid content concentration was 0.8%.

[0181] Column: TSKgelG5000HXL— TSKgel2000HXL (Tosohichi Corporation)

Column temperature: 25 ° C

Eluent: THF

Pump: L6000 (manufactured by Hitachi, Ltd.)

Flow rate: 1. Oml / min

Detection: Rl Model 504 (GL Science Co., Ltd.)

Sample concentration: 0.8%

Standard sample 'calibration curve: Standard polystyrene (TSK standard polystyrene, manufactured by Tosoh Corporation), calibration fountain with 13 samples from Mw = 500 to 000000 was used.

[0182] [Table 1]

Polymer particle dispersion Polymerization 1 t * particles Radical polymerization

Raw material for polysiloxane particles Coarse particle content (pieces / 0.5g) Si0 ₂ vinyl monomer Solid content

B type viscosity average

; ¾ degree> average diameter x2> average diameter X 2.5 Particle diameter Content Production example r

1-methacryloxydipropyl styrene 400 parts 10% by mass 3.5mPa-s> 10000 units> 200 units 10.1 (I m 3% by mass trimethoxysilane ^{4QS | i}

70 parts butyl methacrylate

Production example r-2 acryloxypropylΑηώ _{) 1} unit 6.1 μm 5% by mass Triethoxysilane ^4QSP 1. 6-hexanediol _{ι η} 20% by mass 3.8mPa-s> 10000 units> 200

Diacrylate ¹⁵⁰³⁵ Production Example 3 with ^P -Sinole, 100 parts Divinylbenzene 250 parts 3% by mass 3.1 mPa-s> 10000 units> 200 units 6.9 jum 10% by mass

Trimethoxon Hoon

Cyclohexyl

r-methacryloxypropinole

Production Example 4 ¹⁵⁰ parts of methacrylate 15% by mass 3.8 mPa-s> 10000 units> 200 units 3.7 / m 3 Poor amount ¾

W ethoxysilane ^{4QS | i}

150 parts of divinylbenzene Production example 5 ^r -me ^^, ₁₀₀ parts of mouth pills 400 parts of butyl methacrylate 3% by mass 3.1 mPa-s> 10000 pcs> 200 pcs 25.2 jU m 6% by mass

卜 Limekinkin production example 6,. Ρ '^' ^. 100 parts methyl methacrylate 60 parts 20 parts by mass 3.8 mPa-s> 10000 units> 200 units 4.2 fim 24% by mass

Trimet Thousands

Cyclohexyl

³⁰⁰ parts of r-methacryloxypropyl methacrylate

Production Example 7 10% by mass 3.4mPa «s> 10000 units> 200 units 12.5m 1.5% by mass Triethoxysilane ³¹ ethylene glycol

Dimethacrylate U ⁵¹¹

[0183] Example 1

The polymer particle dispersion obtained in Production Example 1 was classified using a stainless steel wire mesh having an opening of 20 μm (wet classification process). Next, the polymer particle dispersion after wet classification was subjected to solid-liquid separation by natural precipitation. The obtained cake was washed with ion-exchanged water and methanol, and then vacuum-dried at 100 ° C. for 5 hours to obtain a dried product in which particles aggregated. The dried product was pulverized to obtain pulverized particles (recovery rate 99% by mass).

The pulverized particles obtained at this time had a bulk specific gravity of 0.7 g / cm ³ , a particle size of 10. 1 μm, and a water content of 0.5% by mass or less.

[0185] The obtained pulverized particles were put into a high-precision airflow classifier ("DFX5 type" manufactured by Nippon Pneumatic Industrial Co., Ltd.), and the centrifugal force applied to the pulverized particles by a high-speed swirling airflow and a suction blower The particles were classified by adjusting the balance with the drag, and fine particles were obtained at a recovery rate of 85% by mass with respect to the supplied pulverized particles (dry classification step). At this time, the recovery rate of fine particles from the polymer particle dispersion was 84% by mass.

[0186] Example 2

The polymer particle-dispersed solution force pulverized particles obtained in Production Example 2 were prepared by the same steps as in Example 1 (recovery rate 99% by mass). The pulverized particles obtained at this time had a bulk specific gravity of 0.7 g / cm ³ , a particle diameter of 10.1 m, and a water content of 0.5% by mass or less.

[0187] Next, the obtained pulverized particles were put into a rotating rotor type classifier ("Taropplex 100ATP", manufactured by Hosokawa Micron Corporation), and given to the pulverized particles by the rotation speed of the classifying rotor and the supply of air from the intake port. The fine particles were obtained by adjusting the balance between the centrifugal force and the potency, and the fine particles were obtained at a recovery rate of 85% by mass with respect to the supplied pulverized particles (dry classification step). The recovery rate of the fine particles from the polymer particle dispersion at this time was 84% by mass.

[0188] Example 3

In the same manner as in Example 1, pulverized particles were prepared from the polymer particle dispersion obtained in Production Example 3 (bulk specific gravity 0.7 g / cm ³ , particle size 10.1 111, water content 0.5 mass). %, Recovery rate 99% by mass).

[0189] The pulverized particles were mixed with a rotary rotor airflow classifier ("Turbo Classifier TC_15", The product is classified by adjusting the balance between the rotational speed of the classification rotor and the centrifugal force and the effect applied to the pulverized particles by the supply of air from the intake port. Fine particles were obtained at a mass% (dry classification step). The recovery rate of fine particles from the polymer particle dispersion at this time was 84% by mass.

[0190] Example 4

In the same manner as in Example 1, pulverized particles were prepared from the polymer particle dispersion obtained in Production Example 3 (bulk specific gravity 0.7 g / cm ³ , particle size 10.1 111, water content 0.5 mass). % Or less, recovery rate 99%).

[0191] The pulverized particles are put into a Coanda airflow classifier ("Elbow Jet EJ-15", manufactured by Nippon Steel Mining Co., Ltd., feed air: 5kgf, using a slim edge), and the inertia given to the fine particles Classification was performed by adjusting the balance between the force and the effectiveness of the suction blower, and fine particles were obtained at a recovery rate of 85% by mass with respect to the supplied ground particles. At this time, the recovery rate of fine particles from the polymer particle dispersion was 84% by mass.

[0192] Example 5

The polymer particle-dispersed solution force pulverized particles obtained in Production Example 4 were prepared by the same steps as in Example 1 (bulk specific gravity 0.7 g / cm ³ , particle diameter 3.7 11, water content 0.5 Mass% or less, recovery rate 99 mass%).

[0193] Next! /, Put the pulverized particles obtained into a high-precision airflow classifier (“DFX5”, manufactured by Nippon Pneumatic Industry Co., Ltd.) The fine particles were obtained by adjusting the balance between the resultant centrifugal force and drag force, and fine particles were obtained at a recovery rate of 88% by mass with respect to the supplied pulverized particles (dry classification step). At this time, the recovery rate of fine particles from the polymer particle dispersion was 87% by mass.

[0194] Example 6

The polymer particle dispersion solution force pulverized particles obtained in Production Example 5 were prepared by the same steps as in Example 1 (bulk specific gravity 0.7 g / cm ³ , particle diameter 25.2 m, water content 0.5 (Mass% or less, recovery rate 99 mass%).

[0195] Next, the obtained pulverized particles were put into a rotating rotor type classifier ("Tarpoplex 100AT P", manufactured by Hosokawa Micron Corporation), and the rotational speed of the classifying rotor and the intake port Classification was performed by adjusting the balance between the centrifugal force applied to the pulverized particles by the supply of air and the effect, and fine particles were obtained at a recovery rate of 85% by mass with respect to the supplied pulverized particles (dry classification step). The recovery rate of the fine particles from the polymer particle dispersion at this time was 84% by mass.

[0196] Example 7

The polymer particle-dispersed solution force pulverized particles obtained in Production Example 6 were prepared by the same process as in Example 1 (bulk specific gravity 0.7 g / cm ³ , particle diameter 4.2 111, water content 0.5 Mass% or less, recovery rate 99 mass%).

[0197] The pulverized particles are put into a rotating rotor type air classifier ("Turbo Classifier TC_15", manufactured by Nissin Engineering Co., Ltd.), and given to the pulverized particles by the rotation speed of the classifying rotor and the supply of air from the intake port. Classification was performed by adjusting the balance between centrifugal force and efficacy, and fine particles were obtained at a recovery rate of 86% by mass with respect to the supplied pulverized particles (dry classification process). At this time, the recovery rate of the fine particles from the polymer particle dispersion was 85% by mass.

[0198] Example 8

The polymer particle dispersion solution force pulverized particles obtained in Production Example 7 were prepared by the same steps as in Example 1 (bulk specific gravity 0.7 g / cm ³ , particle size 12.5 111, water content 0.5 (Mass% or less, recovery rate 99 mass%).

[0199] The pulverized particles are put into a Coanda airflow classifier ("Elbow Jet EJ-15", manufactured by Nippon Steel Mining Co., Ltd., feed air: 5kgf, using a slim edge), and the inertia given to the fine particles Classification was performed by adjusting the balance between the force and the effectiveness of the suction blower, and fine particles were obtained at a recovery rate of 85% by mass with respect to the supplied ground particles. At this time, the recovery rate of fine particles from the polymer particle dispersion was 84% by mass.

[0200] Comparative Example 1

The polymer particle dispersion obtained in Production Example 1 was classified using a stainless steel wire mesh having an opening of 20 μm (wet classification process). Next, the polymer particle dispersion after wet classification was separated into individual liquids by natural sedimentation. The obtained cake was washed with ion-exchanged water and methanol, and then vacuum-dried at 100 ° C. for 5 hours to obtain a dried product in which particles aggregated. The dried product was pulverized to obtain pulverized particles. [0201] Comparative Example 2

After the polymer particle dispersion obtained in Production Example 2 was classified with a stainless steel wire mesh with an opening of 20 μm, it was further filtered with a cartridge filter (trade name “Ultiple. Profile PUY1UY500” manufactured by Nihon Pall Co., Ltd.). 1 pass treatment (wet classification process). Next, the polymer particles were separated, washed and dried in the same manner as in Comparative Example 1, and the resulting dried product was pulverized to obtain pulverized particles.

[0202] Comparative Example 3

The polymer particle dispersion obtained in Production Example 5 was classified using a stainless steel wire mesh having an opening of 40 μm (wet classification process). Next, polymer particles were separated, washed and dried in the same manner as in Comparative Example 1, and the resulting dried product was pulverized to obtain pulverized particles.

[0203] Table 2 shows the contents of the classification treatment in Examples;! To 8 and Comparative Examples;! To 3, and evaluation results on the obtained fine particles and powder particles. Each evaluation method is as follows.

[0204] [Measurement of average particle size and amount of coarse particles]

A fine particle size distribution measuring device (product name “Multisizer II”, Beckman Coulter Co., Ltd.) was prepared by dispersing 0.5 g of the fine particles obtained in the above Examples and Comparative Examples in 100 g of methanol. Was used to measure the particle size, and the average particle size was calculated on a volume basis.

[0205] The amount of coarse particles 1 (coarse particles having a particle size of twice or more the average particle size) was measured as follows. A fine particle dispersion (viscosity: 3 mPa's, solid content concentration: 0.5% by mass) prepared in the same manner as the above average particle size measurement was used to create a mesh with an opening of 1.75 to 2 times the average particle size ( Filtration was performed under reduced pressure using a nickel filtration, Tokyo Process Service Co., Ltd.) and a suction filtration device equipped with a Buchner funnel in the filtration bell.

[0206] Next! /, Use a scanning electron microscope (SEM, "S_3500N", manufactured by Hitachi, acceleration voltage: 25kV) to observe the entire field at 200x and visually The number of coarse particles (number / 0.5 g) more than twice the average particle size was counted.

[0207] In the case of the amount of coarse particles having an average particle size of 2.5 times or more (coarse particles 2), a mesh having an opening of 2.25-2.5 times the average particle size is used. The procedure was the same as above, except that it was. [0208] [Measurement of the amount of fine particles]

Fine particles obtained in Examples and Comparative Examples were dispersed in 0.5 g of ion-exchanged water to prepare a fine particle dispersion, and a precision particle size distribution analyzer (product name “Multisizer II”, Beckman Coulter Co., Ltd.) Were used to measure the particle diameter and average particle diameter (volume basis). Based on the measurement results, the volume percentage of fine particles having a particle diameter of 1/2 or less of the numerical value obtained by rounding off the first decimal place of the average particle diameter was calculated, and the obtained value was defined as the amount of fine particles.

[0209] [Table 2]

[0210] In Table 2, “Rotating rotor type air classifier 1” used “Turboplex 100ATP” manufactured by Hosokawa Micron Co., Ltd., and “Rotating rotor type air classifier 2” manufactured by Nissin Engineering Co., Ltd. Indicates that “Turbo Classifier TC_15” was used. “Coarse particles 1” is the number of particles (particles / 0.5 g) having a particle size more than twice the average particle size, and “Coarse particles 2” is more than 2.5 times the average particle size. This means the number of particles having a particle size (pieces / 0.5 g), and the `` product recovery rate '' means that the total mass of particles supplied to the classification process in Examples and Comparative Examples is recovered through the classification process. It means the ratio of the total mass of the formed fine particles.

[0211] Production Example 8 (Amino resin crosslinked particles)

A reaction kettle equipped with a cooling line, thermometer and dripping port was charged with 75 parts of melamine, 75 parts of benzoguanamine, 290 parts of formalin with a concentration of 37% and 1.16 parts of an aqueous sodium carbonate solution with a concentration of 10%. A precursor forming mixture was prepared. The mixture was heated to 85 ° C. with stirring and then kept at the temperature for 1.5 hours to obtain an initial condensate. Separately, a nonionic surfactant, Emulgen (registered trademark) 430 (Kao Corporation, polyoxyethylene oleyl ether) 7.5 A surfactant solution prepared by dissolving 5 parts in 2455 parts of ion-exchanged water The initial condensate was added thereto while stirring at a temperature of ° C to obtain an emulsion of an amino resin precursor. To this emulsion, 90 parts of a 5% dodecylbenzenesulfonic acid aqueous solution was added and condensed and cured at a temperature of 70 to 90 ° C. to obtain a suspension containing the amino resin crosslinked particles.

[0212] Production Examples 9, 10 (Amino resin crosslinked particles)

A suspension containing the amino resin crosslinked particles was prepared in the same manner as in Production Example 8, except that the amounts of amino compound and formalin used were changed to those shown in Table 3.

[0213] [Table 3]

[0214] Production Example 11 (polystyrene particles)

50 parts of styrene, 50 parts of ethylene glycol dimetatalylate, 5 parts of an azo polymerization initiator (V-6 65, manufactured by Wako Pure Chemical Industries, Ltd.), 0.5 part of t-ptylnohydroquinone, 0.5 part of sodium lauryl sulfate And 100 parts of ion-exchanged water were mixed, stirred and emulsified to obtain a water dispersion of a polymerizable monomer.

[0215] In a reaction kettle equipped with a cooling line, a thermometer, and a dripping port, 40 parts of monodispersed polystyrene latex (solid content concentration 5%) with a particle size of 1 μm was added and dispersed in 200 parts of ion-exchanged water. The aqueous dispersion of the seed particles was heated to 65 ° C., and the total amount of the polymerizable monomer aqueous dispersion and 200 parts of a 2% aqueous solution of polybulu alcohol were continuously added dropwise over 5 hours. . After completion of the dropping, the temperature was raised to 85 ° C. and maintained at this temperature for another 3 hours to obtain a suspension containing polystyrene particles.

[0216] Production Example 12 (polystyrene particles)

As shown in Table 4, the combination of radical polymerizable monomers was changed, and the amount of monodisperse polystyrene latex (particle size: 0 · 6 111 (Production Example 1 ² ), 0.7 m (Production Example 13)) was added. A polystyrene latex fine particle dispersion solution was prepared in the same manner as in Production Example 11, except that was adjusted appropriately.

[0217] [Table 4]

[0218] Example 9

A configuration in which the polymer dispersion obtained in Production Example 3 is combined with multiple cartridge filters (Pre-filter 1: HC-75, Pre-filter 2: HC-25, Final filter: SLP300, V, Deviation is also manufactured by Loki Techno) Filtration treatment was performed at (wet classification step).

[0219] Next, the dispersion was subjected to solid-liquid separation by natural sedimentation, and the cake obtained was washed with ion-exchanged water and methanol, and then vacuum-dried at 100 ° C for 5 hours, so that the particles did not aggregate. A dried product was obtained. The dried product was pulverized to obtain particles.

[0220] The pulverized fine particles obtained at this time had a bulk specific gravity of 0.7 g / cm ³ , a particle size of 6.9 m, a water content of 0.5 mass% or less, and a recovery rate of 97 mass%.

[0221] This is put into a Coanda airflow classifier (Elbow Jet EJ-15, manufactured by Nippon Steel Mining Co., Ltd., feed air: 5kgf, using a slim edge) to balance the inertial force applied to the fine particles and the drag by the suction blower. The fine particles were obtained by classification with a recovery rate of 89% by mass with respect to the supplied pulverized particles (dry classification step).

[0222] Example 10

The polymer dispersion solution force pulverized particles obtained in Production Example 8 were prepared by the same steps as in Example 9 (bulk specific gravity 0.6 g / cm ³ , particle size 8.5 111, water content 1.0 mass). % Or less, recovery rate 96 mass%).

[0223] The pulverized particles are put into a high-precision airflow classifier (DFX5 type, manufactured by Nippon Pneumatic Industrial Co., Ltd.), and the centrifugal force applied to the pulverized particles by the high-speed swirling airflow and the drag by the suction blower The fine particles were classified by adjusting the balance and classified at a recovery rate of 85% by mass with respect to the supplied pulverized particles (dry classification step).

[0224] Example 11

The polymer dispersion solution force pulverized fine particles obtained in Production Example 11 were prepared by the same steps as in Example 9 (bulk specific gravity 0.7 g / cm ³ , particle size 4. O ^ rn, water content 0. 5 mass% or less, recovery rate 97 mass%).

[0225] The pulverized particles are put into a rotary rotor type airflow classifier (Turbo Classifier TC-15, manufactured by Nissin Engineering Co., Ltd.) and given to the pulverized particles by the rotation speed of the classifying rotor and supply of air from the intake port. Classification by adjusting the balance between centrifugal force and efficacy And fine particles classified at a recovery rate of 85% by mass with respect to the supplied pulverized particles were obtained (dry classification step).

[0226] Example 12

In the same manner as in Example 1, pulverized fine particles were prepared from the polymer particle dispersion obtained in Production Example 10 (bulk specific gravity 0.6 g / cm ³ , particle size 13. l rn, water content 1. 0% by mass or less, recovery rate 99% by mass).

[0227] The pulverized fine particles thus obtained were put into a Coanda airflow classifier (Elbow Jet EJ-15, manufactured by Nippon Steel Mining Co., Ltd., feed air: 5 kgf, using a slim edge), and from the rotational speed of the classification rotor and the intake port The fine particles were classified by adjusting the centrifugal force applied to the pulverized particles and the tolerance of the effect by supplying the air, and the fine particles classified at a recovery rate of 85% by mass with respect to the supplied pulverized particles (dry classification step).

[0228] Example 13

In the same manner as in Example 1, pulverized fine particles were prepared from the polymer particle dispersion obtained in Production Example 9 (bulk specific gravity 0.6 g / cm ³ , particle diameter 2. O ^ m, water content 1. 0 mass% or less, recovery rate 99 mass%).

[0229] The obtained pulverized fine particles were put into a high-precision airflow classifier (DFX5 type, manufactured by Nippon Pneumatic Industrial Co., Ltd.), and the centrifugal force applied to the pulverized particles by the high-speed swirling airflow and the drag force by the suction probe By adjusting the balance, fine particles classified at a recovery rate of 80% by mass with respect to the supplied ground particles were obtained.

[0230] Example 14

In the same manner as in Example 1, pulverized fine particles were prepared from the polymer particle dispersion obtained in Production Example 12 (bulk specific gravity 0.7 g / cm ³ , particle diameter 6.5 111, water content 0. 5 mass% or less, recovery rate 99 mass%).

[0231] The obtained pulverized fine particles were put into a Coanda airflow classifier (Elbow Jet EJ-15, manufactured by Nippon Steel Mining Co., Ltd., feed air: 5kgf, using a slim edge), and the rotation speed of the classification rotor and the intake port Classification was performed by adjusting the centrifugal force applied to the pulverized particles and the tolerance of the effect by supplying air, and fine particles classified at a recovery rate of 87 mass% with respect to the supplied pulverized particles were obtained. [0232] Example 15

In the same manner as in Example 1, pulverized fine particles were prepared from the polymer particle dispersion obtained in Production Example 13 (bulk specific gravity 0.7 g / cm ³ , particle size 9.3 m, water content 0. 5 mass% or less, recovery rate 99 mass%).

[0233] The obtained pulverized fine particles are fed into a rotary rotor type airflow classifier (Turbo Classifier TC 15, manufactured by Nissin Engineering Co., Ltd.) and given to the pulverized particles by the rotation speed of the classification rotor and the supply of air from the intake port. Classification was performed by adjusting the balance between centrifugal force and efficacy, and fine particles classified at a recovery rate of 83% by mass with respect to the supplied ground particles were obtained.

[0234] Comparative Example 4

[0235] The obtained pulverized fine particles were put into a Coanda airflow classifier (Elbow Jet EJ-15, manufactured by Nippon Steel Mining Co., Ltd., feed air: 5 kgf, using a slim edge), and the rotation speed of the classification rotor and the intake port The fine particles were classified by adjusting the centrifugal force applied to the pulverized particles and the tolerance of the effect by supplying the air, and the recovery rate of 75% by mass with respect to the supplied pulverized particles.

[0236] Comparative Example 5

A fine powder was prepared from the polymer particle dispersion obtained in Production Example 3 (bulk specific gravity 0.7 g / cm ³ , particle size) in the same manner as in Example 1, except that the power for wet classification was not used. 6.9, water content 0.5 mass% or less).

[0237] The obtained pulverized fine particles are fed into a rotary rotor type airflow classifier (Turbo Classifier TC 15 manufactured by Nissin Engineering) and given to the pulverized particles by the rotation speed of the classification rotor and the supply of air from the intake port. Classification was performed by adjusting the balance between centrifugal force and efficacy, and fine particles classified at a recovery rate of 90% by mass with respect to the supplied ground particles were obtained (first dry classification). Thereafter, the same dry classification process was repeated to obtain fine particles classified at a recovery rate of 90% by mass with respect to the supplied pulverized particles (the second dry classification).

Contents of classification treatment in Examples 9 to 13 and Comparative Example 4, fine particles and powder obtained Table 5 shows the evaluation results for body particles. Each evaluation method is as described above.

[Table 5]

[0240] Note that Comparative Example 5 is an example in which dry classification was repeated twice as a classification step. Coarse particles were not sufficiently removed only by repeated dry classification. In addition, it can be seen that the product recovery rate tends to decrease by repeating dry classification, and it is difficult to obtain industrial product yields only by dry classification.

[0241] Example 16 Production of antiglare film

3 parts by mass of each resin particle obtained in Examples 1, 9, 10 and Comparative Example 4 and 20 parts by mass of toluene were sufficiently stirred and mixed. In the mixed solution, 40 parts by mass of an acrylic ionizing radiation curable resin, 2 parts by mass of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals, “Irgacure (registered trademark) 907”), 23 parts by mass of methyl ethyl ketone, ethylene glycol mono Two parts by weight of butyl ether and a leveling agent (BYK320, manufactured by BYK-Chem Co., Ltd.) were added, and the mixture was sufficiently stirred to prepare a coating solution.

[0242] The coating solution was applied to one side of an 80 m thick triacetyl cellulose film ("Fujitac (registered trademark)" manufactured by Fuji Photo Film Co., Ltd.) using a bar coater. The obtained coating film was dried with a dryer at 80 ° C., and then an antiglare film was produced by irradiating 300 mJ / cm ² of ultraviolet rays with a high pressure mercury lamp to cure the resin component.

[0243] attaching a black film on the back surface of the antiglare film, it reflects the fluorescent lamp lOOOOcd / m ² from the position apart 2m from the film, and evaluate the degree of blurring of the reflected image on the following criteria. The results are shown in Table 6.

○: The outline of the fluorescent lamp cannot be identified.

X: The fluorescent lamp outline can be clearly identified.

[0244] For each anti-glare film, using a mapping measuring instrument (ICB-IDD, manufactured by Suga Test Instruments Co., Ltd.) and an optical comb with a width of 0.5 mm, transmission sharpness (image sharpness) according to JIS K7105 Was measured.

[0245] In addition, each anti-glare film is connected to a personal computer on a liquid crystal monitor (15 inch XGA, TFT-TN system, front brightness: 350 cd / m ² , front contrast: 300 to 1, surface AG: none) It was bonded to the surface, and the character blur was evaluated according to the following criteria. The results are shown in Table 6.

〇: The outline of the character is completely out of focus! X: The outline of the character is blurred and a strong sense of incongruity is felt.

[0246] [Table 6]

[0247] As can be seen from Table 6, the antiglare films obtained using the particles of Examples 1, 9 and 10 all have excellent antiglare properties and visibility (no blurring of characters). Met . On the other hand, although the antiglare film produced using the particles of Comparative Example 4 having a large amount of coarse particles exceeding twice the average particle diameter has antiglare properties, the coarse particles contained in the antiglare film are like lenses. It is thought that the film surface was damaged due to the action of the coarse particles, and as a result, it was difficult to visually recognize the characters.

Industrial applicability

[0248] The fine particles of the present invention are those in which the content of coarse particles and fine particles that deviate from the preferred range of particle size is reduced to a low level. Therefore, various optical films or sheets (anti-glare sheet, light diffusion film, etc.) produced using force and fine particles have disadvantages derived from coarse particles and reduced transparency derived from fine particles. This is considered to be difficult to occur. In addition, since unevenness is uniformly formed in the surface, it is considered that excellent optical properties (for example, antiglare property and light diffusibility) are exhibited.

Claims

The scope of the claims

[1] Fine particles characterized in that the number of coarse particles having a particle size of 2 or more times the average particle size is 1,000 particles / 0.5 g or less.

[2] The fine particle according to claim 1, wherein the fine particle is an organic-inorganic composite containing an organic polymer skeleton and a polysiloxane skeleton.

[3] The method for producing fine particles according to claim 1 or 2,

A step of wet-classifying a fine particle dispersion having a solid content concentration of 0.5 to 50 mass% and a B-type viscosity of 0.5 to 20 mPa * s,

A step of drying and pulverizing the fine particles after wet classification to form powder fine particles having a moisture content of 0.05 to 2% by mass;

A method for producing fine particles, comprising a step of dry-classifying the powder fine particles.

[4] A resin composition comprising the fine particles according to claim 1 or 2.

[5] A coating composition comprising the resin composition according to claim 4.

[6] An optical film obtained by applying the coating composition according to claim 5 on a substrate.

7. The optical film according to claim 6, which is used as a light diffusion film.

8. The optical film according to claim 6, which is used as an antiglare film.