JP6326336B2 - Method for producing composite particles - Google Patents

Description

  The present invention relates to a method for producing composite particles formed from core particles and child particles (fine particles).

  The composite particles in which the core particles are coated with the child particles smaller than the core particles (hereinafter sometimes referred to as “fine particles”) are the characteristics of the core particles as a whole (thermal characteristics, mechanical characteristics, electrical characteristics). In addition, the surface of the composite particles can exhibit the characteristics of the fine particles (electrical characteristics, hydrophilicity / hydrophobicity, etc.) while retaining the magnetic characteristics, electromagnetic characteristics, etc. Can be formed. For this reason, composite particles are electronic parts related materials, film related materials, resin molding related materials, paint related materials, optical related materials, medical related materials, printing related materials, information recording related materials, information communication related materials, construction related materials, etc. Is used in a wide range of applications.

  Various methods have been proposed for producing such composite particles. For example, Patent Document 1 discloses a powder particle group (mixed powder) composed of mother particles and child particles, or a powder particle group (ordered mixture) in which child particles are previously attached to the surface of the mother particles. There has been proposed a method of immobilizing child particles on the surface of a mother particle by giving a mechanical impact action and repeating this. However, in the method described in Patent Document 1, since it is necessary to give a high impact, the mother particles having insufficient strength may be destroyed, and composite particles may not be obtained.

  In addition, as a method of using an adhering substance instead of a high impact as a composite means, Patent Document 2 discloses that polymer particles and inorganic particles are dispersed in an aqueous solution of a water-soluble polymer to insolubilize the water-soluble polymer. There has been proposed a method of obtaining composite particles by attaching inorganic particles to the surface of polymer particles by (crosslinking reaction) and filtering. However, in the method described in Patent Document 2, the step of attaching the inorganic particles to the surface of the polymer particles must be carried out in a wet manner, and therefore, further filtration and drying steps are required to obtain composite particles, and the procedure is as follows. It was complicated.

JP-A-8-131818 JP 2006-52332 A

  The present invention has been made in view of such circumstances, and the purpose thereof is a simple means and composites them regardless of the kind of core particles and child particles, for example, the child particles are added to the core particles. An object of the present invention is to provide a method for fixing and producing composite particles with little aggregation.

  While the inventors of the present invention have made extensive studies to solve the above problems, the method described in Patent Document 2 has a high solvent content, for example, a solid phase and a liquid layer that can be separated by filtration. In contrast to the stirring in the slurry state, the content of the solvent is greatly reduced and concentrated, and the binder is adhered to the surface of the core particles in a slightly wet state to the extent that the free liquid phase portion is substantially absent. I tried to coat a resin layer with a function. Then, at this stage, once the aggregates with low fluidity (aggregates) were formed and the flow state deteriorated, when the child particles were added and mixed there, the child particles were fixed to the binder. The adhesiveness between the binders is cut off while being formed, and the fluidity is drastically improved to prevent the core particles from aggregating. On the other hand, the child particles are reliably fixed to the core particles by the resin layer coated on the core particles. Thus, the present invention has been completed by finding that composite particles can be formed by a simple operation because the formation of aggregates of only child particles can be suppressed.

  That is, the method for producing composite particles according to the present invention includes a first composition containing core particles, a resin, and a solvent, having a solvent content of 0.5% by mass or more and a fluidity index of 35 or more. The first composition is prepared and mixed with child particles having a particle size smaller than that of the core particles. The solvent content in the first composition is preferably 30% by mass or less.

Further, the ratio (d _f / d _c ) of the average particle diameter d _f of the child particles and the average particle diameter d _c of the core particles is preferably 0.2 or less.

Further, the addition amount of the child particles is calculated by the following formula: Calculated child particle addition amount (W ₂ ) = core particle specific surface area (S) × core particle weight (W ₁ ) / child particle ratio projected area (A)
It is preferable that it is 0.4 times or more and 1.2 times or less of the calculating element particle addition amount (W ₂ ) obtained in ( ₁ ).
Moreover, it is preferable that the said resin contains a heat | fever or photocurable resin.

  The production method of the present invention is to prepare a first composition which is a powder containing core particles, a resin, and a solvent and has a fluidity index of 35 or more, and the first composition and the child particles are mixed. Therefore, it is possible to easily obtain composite particles with little aggregation regardless of the types of core particles and child particles.

FIG. 1 represents a schematic cross-sectional view of the composite particle of the present invention. FIG. 2 shows a scanning electron microscope (SEM) of the composite particles of Example 1.

1. Method for producing composite particles The method for producing composite particles of the present invention comprises a core particle, a resin (preferably an adhesive resin or a coating resin), and a trace amount of solvent, and has a fluidity index of 35 or more. It is characterized in that after preparing a composition in a weakly wet state (hereinafter referred to as the first composition), child particles are added to the first composition and mixed (stirred). First, in the first composition, the core particles are coated and bound with an adhesive resin to form large aggregates. However, when the child particles are added and mixed (stirred) while maintaining the weakly wet state of the first composition, the binding between the core particles and the core particles is cut, while the newly generated core particle surfaces and Binding is formed between the core particle and the core particle-child particle, and the binding between the core particle and the child particle is not broken. As a result, it is possible to strongly fix the child particle on the surface of the core particle while eliminating aggregation, and to obtain a desired composite particle Can be formed. In such a production method of the present invention, the amount of the solvent used can be suppressed, so that it is excellent in cost and is excellent in that a step such as solid-liquid separation is unnecessary. Therefore, since there are few manufacturing processes and few devices are used, quality control is easy and stable production is possible. Furthermore, the processing apparatus can be easily made large, and since the filling rate can be increased because the amount of the solvent is small, the mass productivity is excellent.
Further, in the production method of the present invention, the entire core particle is covered with the adhesive resin, and the effect of covering the weak points (oxidation, hygroscopicity, solubility, etc.) of the core particle with the adhesive resin or child particles is also expected. Is done. In particular, in the present invention, it is possible to adjust the covering state with the child particles. When a part of the core particle is coated with the child particle, a composite particle having both the characteristics of the core particle and the surface property of the child particle is obtained, and the entire surface of the core particle is coated with the child particle. Is more effective in covering the weak points (oxidation, hygroscopicity, solubility, etc.) of the core particles.

As described above, in the present invention, it is important to adjust the amount of solvent so that the first composition (core particles, adhesive resin, solvent) is in a weakly wet state. The content of the solvent with respect to the total of the core particles, the adhesive resin (adhesive resin solid content) and the solvent is set within a range where the weakly wet state can be achieved, and specifically, 0.5% by mass or more, preferably Is 1% by mass or more, more preferably 2% by mass or more, and further preferably 3% by mass or more. Moreover, it is preferable that content of a solvent is 30 mass% or less, More preferably, it is 25 mass% or less, More preferably, it is 20 mass% or less, More preferably, it is 15 mass% or less.
In the first composition, the solvent is preferably 0.1 parts by mass or more, more preferably 0.00 parts by mass with respect to 100 parts by mass in total of the core particles and the adhesive resin (adhesive resin solid content). 5 parts by mass or more, more preferably 1 part by mass or more, preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and still more preferably 20 parts by mass or less.
When the content of the solvent is within this range, the resin layer coated on the core particles has adhesiveness to such an extent that the child particles adhere to each other, and is optimal for the combination of the child particles and the core particles.

The fluidity index of the first composition is preferably 35 or more, more preferably 45 or more, and still more preferably 55 or more. The larger the fluidity index, the better the fluidity. The fluidity index is usually 100 or less.
The fluidity index is obtained by measuring an angle of repose, a degree of compression, a spatula angle, and a degree of uniformity or agglomeration, calculating an index for each parameter, and summing them. The angle of repose means the maximum angle of a slope that maintains stability without spontaneous collapse when powders are stacked, and can be measured by injecting a sample through a funnel by vibrating a standard sieve. The compression degree can be obtained as a ratio of these two numerical values by measuring a loose apparent specific gravity and a hard apparent specific gravity. The spatula angle can be measured as the angle of the powder volume on the spatula. Furthermore, the degree of aggregation can be calculated as a mass ratio of the powder remaining on the sieve by vibrating with a standard sieve for a certain period of time, and the uniformity can be measured by particle size distribution or sieving, It can be calculated as the value obtained by dividing the 60% sieve particle size by the 10% sieve particle size.
The fluidity index, which is the sum of these indices, can be measured using, for example, a powder tester PT-X type (manufactured by Hosokawa Micron Corporation).

The amount of the solvent can be adjusted appropriately. For example, if the predetermined amount of the solvent is used, and the predetermined amount of the solvent, the core particles, and the adhesive resin (adhesive resin solid content) are mixed, Thereafter, the first composition in a weakly wet state can be prepared without carrying out any special solvent preparation means (solvent removal (concentration, etc.), addition of solvent, etc.). When a predetermined amount or less of a solvent is used, the solvent may be added at an appropriate stage. When a predetermined amount or more of a solvent is used, the solvent may be removed (concentration, etc.) at an appropriate stage. . Further, even when a predetermined amount of solvent is used, a solvent may be added within a range in which a weakly wet state is maintained (specifically, a range in which the specific solvent amount can be maintained). You may remove (concentrate etc.).
The mixing method of the solvent, the core particles, and the adhesive resin (adhesive resin solid content) when preparing the first composition is not particularly limited, and examples thereof include airflow mixing and stirring mixing. Is preferred. In the case of stirring and mixing, the rotation speed is preferably 100 to 10,000 rpm, and more preferably 500 to 5000 rpm.
As a mixer used for mixing, for example, a hemisphere mixer (manufactured by Sugiyama Heavy Industries), an axial mixer (manufactured by Sugiyama Heavy Industries), a fluidized bed granulation drying coating apparatus (manufactured by Paulek), etc .; -Blade type of granulator (manufactured by Taiheiyo Kiko Co., Ltd.), professional share mixer (manufactured by Taiheiyo Kiko Co., Ltd.), high speed mixer (manufactured by Earth Technica Co., Ltd.), super mixer (manufactured by Kawata Co., Ltd.), ribbon mixer (manufactured by Nishimura Kikai Co., Ltd.) And the like. In addition to the mixing mechanism, the mixer preferably includes a liquid addition nozzle such as a spray nozzle, a powder addition port, an exhaust port, a heating mechanism, and the like.

  Concentration is preferred as a method for removing the solvent. Concentration includes various solvent evaporation methods by vaporization, and may be, for example, volatilization or evaporation. The concentration may be appropriately heated, and the temperature of the solvent is preferably 30 to 90 ° C, more preferably 40 to 85 ° C. In addition, when a preliminary composition is prepared from the solvent, the core particles, and the resin solids, and then the solvent is removed to prepare the first composition, the amount of the solvent at the time of preparing the preliminary composition is 100%. In the mass part, it is preferably 1 part by mass or more, more preferably 2 parts by mass or more, further preferably 3 parts by mass or more, preferably 25 parts by mass or less, more preferably 20 parts by mass or less. Yes, more preferably 15 parts by mass or less. Further, in the preliminary composition, the solvent is preferably 0.1 parts by mass or more, more preferably 0.5 parts with respect to 100 parts by mass in total of the core particles and the adhesive resin (adhesive resin solid content). It is preferably not less than 1 part by mass, more preferably not less than 1 part by mass, and preferably not more than 40 parts by mass, more preferably not more than 30 parts by mass, still more preferably not more than 20 parts by mass.

  Furthermore, the first composition is obtained by stirring the core particles, the adhesive resin (adhesive resin solid content), and the solvent for 1 hour or more (more preferably 1.5 hours or more) in a weakly wet state. It is preferable that Thereby, the uniformity of a 1st composition can be improved. The stirring time is usually preferably 10 hours or less, more preferably 5 hours or less, and even more preferably 4 hours or less.

The order of mixing the core particles, the adhesive resin (adhesive resin solid content), and the solvent is not particularly limited. For example, the adhesive resin (adhesive resin solid content) and the solvent are mixed in advance and the adhesive resin mixed. It is preferable to prepare a liquid and mix the core particles and the adhesive resin mixed liquid. This makes it possible to more uniformly coat the core particle surface with the adhesive resin (adhesive resin solid content). From the viewpoint of being suitable for coating on the surface of the core particles, the viscosity of the adhesive resin mixed solution is preferably 1 mPa · s or more and 1 Pa · s or less, more preferably 5 mPa · s or more and 0.5 Pa · s or less, and still more preferably. 10 mPa · s or more and 0.1 Pa · s or less. The viscosity can be measured with a B-type rotational viscometer. For example, “LV-T” (LV spindle (rotor) LV-3, LV-2, LV-1, rotation speed 30 rpm, manufactured by EKO Eihiro Seiki Co., Ltd., It can be measured under conditions of room temperature (25 ° C.).
As the viscosity of the adhesive resin mixture increases, the first composition is more easily wetted, and the child particles and the core particles can be easily combined. Further, as the viscosity of the adhesive resin mixed solution is smaller, the core particles and the adhesive resin mixed solution can be more easily and uniformly mixed.

  The viscosity of the adhesive resin mixed solution can be adjusted by, for example, the concentration of the adhesive resin (adhesive resin solid content), and the concentration of the adhesive resin (adhesive resin solid content) is in 100% by mass of the adhesive resin mixed solution. It is preferably 5% by mass or more, more preferably 10% by mass or more, further preferably 20% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, still more preferably. It is 50 mass% or less. The solvent is preferably 43 parts by mass or more, more preferably 65 parts by mass or more, and still more preferably 1100 parts by mass or more with respect to 100 parts by mass of the adhesive resin (adhesive resin solid content). It is preferable that it is 1900 mass parts or less, More preferably, it is 900 mass parts or less, More preferably, it is 400 mass parts or less.

  Further, the resin amount in the adhesive resin mixed solution is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and further preferably 1 part by mass or more with respect to 100 parts by mass of the core particles. 90 parts by mass or less, more preferably 70 parts by mass or less, still more preferably 50 parts by mass or less, and particularly preferably 30 parts by mass or less.

  When preparing the preliminary composition or the first composition by mixing the core particles and the adhesive resin mixed solution, the adhesive resin mixed solution may be added to the core particles. For example, it is preferable to add the adhesive resin mixed solution in small amounts sequentially or continuously, and it is more preferable to add the adhesive resin mixed solution by spraying the core particles. Thereby, it is possible to uniformly mix the core particles and the adhesive resin mixed solution while suppressing the generation of the free liquid phase portion.

  By mixing the first composition thus obtained and the child particles, the surface of the core particles is coated with a resin layer, and the core particles and the child particles are bonded by this resin layer. And since reattachment of binders is suppressed by this child particle, aggregation of core particles and aggregation of child particles are suppressed, and a composite particle can be manufactured. As a mixing method, various methods capable of applying a shearing force can be employed, and the same mixing method as that used in the preparation of the first composition can be employed as long as the shearing force can be applied. . Specifically, stirring and mixing are preferable. Moreover, the mixer similar to the time of preparation of a 1st composition can be used in the range which can make a shear force act also for a mixer. Specifically, a blade type mixer is preferable.

Since the child particles are present near the surface of the core particles during the formation of the composite particles, the child particles are fixed to the surface of the core particles, and composite particles with less aggregation can be efficiently produced. In order to suppress aggregation, it is preferable to adjust the addition amount of the core particles within a certain range. Specifically, the amount of child particles added is calculated by the following formula: child particle addition amount (W ₂ ) = specific surface area of core particles (S) × core particle weight (W ₁ ) / specific projected area of child particles (A)
It is preferably be calculated subparticles amount (W ₂₎ of 0.4 times that obtained in, more preferably 0.5 times or more, further preferably 0.6 times or more, 1.2 times or less Preferably, it is 1.1 times or less, more preferably 1.05 times or less. If the added amount of the child particles is 0.4 times or more of W ₂ , the child particles can effectively cut off the aggregation of the core particles, improving the fluidity of the mixture of the first composition and the child particles. , Aggregation of the composite particles can be suppressed. Further, when the amount of the child particles added is 1.2 times or less of W ₂ , the amount of the child particles that are released without adhering to the core particles can be suppressed, and the original properties of the core particles (thermal properties, mechanical properties) Characteristics, electrical characteristics, magnetic characteristics, electromagnetic characteristics, and the like).

In the above formula, the specific surface area (S) of the core particle means the surface area of the core particle per unit mass, and can be calculated based on the following formula assuming that the shape of the core particle is a sphere.
Specific surface area of core particle (S) = 6 / (apparent density of core particle × volume average particle diameter of core particle)
Further, the specific projected area (A) of the child particles can be calculated based on the following formula assuming that the shape of the child particles is a sphere.
Specific projected area of child particles (A) = 3 / (2 × volume average particle diameter of child particles × apparent density of child particles)

  The first composition and the child particles are kept constant in a weakly wet state in which the solvent content is 0.2% by mass or more and 30% by mass or less in the total 100% by mass of the first composition and the child particles. It is preferable to continue mixing for more than an hour. The content of the solvent is preferably 1% by mass or more, more preferably 2% by mass or more, further preferably 3% by mass or more, and 25% by mass in the total 100% by mass of the first composition and the child particles. % Or less, more preferably 20% by mass or less.

  When a shearing force is applied when the mixture of the first composition and the child particles is in a weakly wet state, a new surface is formed, and when the child particles protrude from the surface, recombination of the surface is inhibited. And the surface is maintained. Here, since the bond between the core particle and the core particle is weaker than the bond between the child particle and the core particle or between the child particle and the child particle, when a shear force is applied, the core particle and the core particle are dissociated, On the other hand, the bond between the child particle and the core particle or between the child particle and the child particle tends to be maintained. Under such circumstances, the mixing is continued for a certain period of time, so that the core particles and the core particles are separated into individual particles and at the same time the bond between the child particles and the core particles is maintained. It becomes easy to obtain composite particles in which is immobilized. Therefore, the mixing time of the first composition and the child particles is preferably, for example, 5 minutes or more, more preferably 10 minutes or more, and further preferably 20 minutes or more. Further, the mixing time is preferably, for example, 100 minutes or less, more preferably 80 minutes or less, and even more preferably 70 minutes or less.

  Moreover, you may heat when mixing a 1st composition and a child particle. The heating temperature is preferably 30 to 90 ° C, for example, and more preferably 40 to 85 ° C.

After mixing the first composition and the child particles, an adhesive resin (adhesive resin solid content) may be further cured as necessary.
When the adhesive resin (adhesive resin solid content) contains a thermosetting resin, the heating temperature for curing is preferably, for example, 80 ° C or higher, more preferably 90 ° C or higher, and still more preferably 95 ° C. It is above, it is preferable that it is 170 degrees C or less, More preferably, it is 140 degrees C or less, More preferably, it is 120 degrees C or less. Moreover, it is preferable that heating time is normally 1 to 200 minutes, More preferably, it is 5 to 60 minutes, More preferably, it is 10 to 30 minutes.
Moreover, what is necessary is just to irradiate active energy rays, such as an ultraviolet-ray with a wavelength of 300-450 nm, for example, for the hardening, when adhesive resin (adhesive resin solid content) contains a photocurable resin. The irradiation time of the active energy ray is usually preferably 1 to 120 minutes, more preferably 5 to 60 minutes, and further preferably 10 to 30 minutes.

  Examples of the core particles applicable to the production method of the present invention as described above include organic particles, inorganic particles, metal particles, metal compound particles, and the like, and any of them can be used.

  The organic particles only need to contain an organic component, and this organic component may be, for example, a polymer component or an organic-inorganic composite component. The polymer component may be formed from either a natural polymer compound or a synthetic polymer compound, or may be formed from both.

  Examples of the natural polymer compound include proteins such as glue, gelatin, casein, and albumin; natural rubbers such as gum arabic and tragacanth; glucosides such as saponin; alginic acid, propylene glycol alginate, triethanolamine alginate, ammonium alginate And alginic acids such as; cellulose derivatives such as methylcellulose, carboxymethylcellulose, hydroxyethylcellulose, and ethylhydroxycellulose;

Examples of the synthetic polymer compound include heat or photocurable resins and thermoplastic resins. Examples of the thermosetting or photosetting resin (preferably thermosetting resin) include phenol resins; resins obtained by reaction with formaldehyde such as xylene / formaldehyde resins, ketone / formaldehyde resins, urea resins, melamine resins, and aniline resins; Furan resin; alkyd resin; polyester resin; epoxy resin; benzoguanamine resin;
Examples of thermoplastic resins include olefin resins such as polyethylene and polypropylene; polystyrene; polyvinyl acetate; (meth) acrylic resins such as polyacrylate and polymethacrylate; vinyl halide resins such as polyvinyl chloride and polyvinylidene chloride; Acrylonitrile; Amide resin such as aliphatic polyamide and aromatic polyamide; Polycarbonate; Silicone resin; Polyester resin such as polyethylene terephthalate and polybutylene terephthalate; ABS resin (acrylonitrile-butadiene-styrene resin), ACS resin (chlorinated polyethylene-acrylonitrile- Styrene resin), AES resin (acrylonitrile-ethylene-styrene resin) and other vinyl-based graft copolymer resins; urethane resins; polyphenylene ethers, polyphenols Phenylene group-containing resins such as lenoxide and polyphenylene sulfide; fluororesins; polyether resins such as polyetheretherketone, polyetherketone and polyethersulfone; polyvinylether resins; polyvinylketone resins; polyxylylene resins; polysulfone resins; Moreover, the copolymer which combined suitably the monomer which comprises these resin is also contained. Furthermore, it may be a resin (vinyl resin) obtained by radical polymerization of a monomer having a vinyl group (vinyl monomer) described later.

  Examples of the organic-inorganic composite component include a silicone resin, and a material containing the organic component and a polysiloxane skeleton (for example, a resin obtained by radical polymerization of a monomer having a polysiloxane skeleton and a vinyl group (vinyl). And the like which contain as a constituent component a material obtained by combining a resin with a resin).

  The monomer having a vinyl group (vinyl monomer) used in the vinyl resin used for the synthetic polymer compound or the organic-inorganic composite component may be either a non-crosslinkable monomer or a crosslinkable monomer. Good. Preferred vinyl resins include homopolymers or copolymers of non-crosslinkable monomers having a vinyl group, copolymers of crosslinkable monomers having a vinyl group and noncrosslinkable monomers having a vinyl group, etc. Is included.

  Examples of the crosslinkable monomer having a vinyl group include a monomer having two or more vinyl groups in one molecule (hereinafter referred to as a radical crosslinkable monomer), one vinyl group in one molecule, Monomers (hereinafter referred to as functional group type single monomers) having binding functional groups other than vinyl groups (protic hydrogen-containing groups such as carboxy groups and hydroxy groups, terminal functional groups such as alkoxy groups, carbamoyl groups, and glycidyl groups). Body)). However, in order to form a crosslinked structure with a functional group-type monomer, it is necessary to have a counterpart monomer that can react (bond) with the binding functional group of the monomer.

  Examples of the radical crosslinkable monomer include allyl (meth) acrylates such as allyl (meth) acrylate; alkanediol di (meth) acrylate (for example, ethylene glycol di (meth) acrylate, 1,4-butanediol) Di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth) acrylate, 1,10-decanediol di (meth) acrylate, 1,3-butylene di (meth) Acrylate, etc.), polyalkylene glycol di (meth) acrylate (for example, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, decaethylene glycol di (meth) acrylate, pentadecaethylene glycol di (meth) acrylate Penta contactor ethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polytetramethylene glycol di (meth) acrylate, etc.), dimethylolpropane di (meth) acrylate, etc. (Meth) acrylates; trimethylolpropane tri (meth) acrylate, dimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, trimethylolpropane propoxytri (meth) acrylate, trimethylolpropane ethylene glycol addition Triacrylate, tetramethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, etc. Acrylates; tetra (meth) acrylates such as tetramethylolmethanetetra (meth) acrylate, tetramethylolpropanetetra (meth) acrylate, pentaerythritol tetra (meth) acrylate; penta (meth) acrylate such as dipentaerythritol penta (meth) acrylate ) Acrylates; hexa (meth) acrylates such as dipentaerythritol hexa (meth) acrylate; aromatic hydrocarbon crosslinking agents such as divinylbenzene, divinylnaphthalene, and derivatives thereof (preferably styrenic polymers such as divinylbenzene) Functional monomers); heteroatom-containing crosslinking agents such as N, N-divinylaniline, divinyl ether, divinyl sulfide, and divinyl sulfonic acid; Among these, (meth) acrylates (polyfunctional (meth) acrylate) having two or more (meth) acryloyl groups in one molecule and aromatic hydrocarbon crosslinking agents (especially styrene polyfunctional monomers) are included. preferable. Among the (meth) acrylates having two or more (meth) acryloyl groups in one molecule, (meth) acrylates having three or more (meth) acryloyl groups in one molecule are particularly preferable. Among these, acrylates having 3 or more acryloyl groups in one molecule are preferable. Among the styrenic polyfunctional monomers, monomers having two vinyl groups in one molecule such as divinylbenzene are preferable. A radical crosslinkable monomer may be used independently and may use 2 or more types together.

  Examples of the functional group type monomer include monomers having a carboxy group such as (meth) acrylic acid; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl ( Monomers having hydroxy groups such as hydroxy group-containing (meth) acrylates such as (meth) acrylate, hydroxy group-containing styrenes such as p-hydroxystyrene; 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meta) ) Monomers having alkoxy groups such as alkoxy group-containing (meth) acrylates such as acrylate, 2-butoxyethyl (meth) acrylate, and alkoxystyrenes such as p-methoxystyrene; carbamoyloxy (meth) acrylate, carbamoyloxy Such as ethyl (meth) acrylate Monomers having Rubamoiru group; monomer having an epoxy group such as glycidyl (meth) acrylate; and the like. A functional group type monomer may be used independently and may use 2 or more types together.

  Examples of the non-crosslinkable monomer having a vinyl group include a monomer having one vinyl group in one molecule (hereinafter referred to as a monofunctional monomer), or the functional when no counterpart monomer is present. Examples include basic monomers. The monofunctional monomer includes a (meth) acrylate monofunctional monomer and a styrene monofunctional monomer. Examples of (meth) acrylate monofunctional monomers include (meth) acrylic acid; methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate, tert-butyl (meth) ) Acrylate, isobutyl (meth) acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate , Alkyl (meth) acrylates such as stearyl (meth) acrylate and 2-ethylhexyl (meth) acrylate; cyclopropyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meta Cycloalkyl (meth) acrylates such as acrylate, cyclooctyl (meth) acrylate, cycloundecyl (meth) acrylate, cyclododecyl (meth) acrylate, isobornyl (meth) acrylate, 4-tert-butylcyclohexyl (meth) acrylate; Examples include aromatic ring-containing (meth) acrylates such as phenyl (meth) acrylate, benzyl (meth) acrylate, tolyl (meth) acrylate, and phenethyl (meth) acrylate, and alkyl (meth) acrylates such as methyl (meth) acrylate. preferable. Examples of styrenic monofunctional monomers include styrene; alkyl styrenes such as o-methyl styrene, m-methyl styrene, p-methyl styrene, α-methyl styrene, and p-tert-butyl styrene; o-chlorostyrene, m-chloro Halogen group-containing styrenes such as styrene and p-chlorostyrene; and the like, and styrene is preferable. A monofunctional monomer may be used independently and may use 2 or more types together.

  When the polymer component (synthetic polymer compound) is composed of a vinyl resin, the vinyl monomer is preferably a combination of both a non-crosslinkable monomer and a crosslinkable monomer. Is preferably, for example, 20 parts by mass or more, more preferably 40 parts by mass or more, and still more preferably 60 parts by mass with respect to 100 parts by mass in total of the non-crosslinkable monomer and the crosslinkable monomer. Part or more, particularly preferably 70 parts by weight or more, preferably 99 parts by weight or less, more preferably 90 parts by weight or less, and still more preferably 85 parts by weight or less.

  Further, when the vinyl resin constitutes a part of the organic-inorganic composite component, the vinyl resin includes a non-crosslinkable monomer alone or a copolymer, and a non-crosslinkable monomer and a crosslinkable monomer. A copolymer is preferred. The proportion of the non-crosslinkable monomer is, for example, preferably 50 parts by mass or more, more preferably 60 parts by mass or more, with respect to 100 parts by mass in total of the non-crosslinkable monomer and the crosslinkable monomer. More preferably, it is 70 parts by mass or more, and preferably 100 parts by mass or less.

  The polysiloxane skeleton constituting the organic-inorganic composite component is formed by hydrolyzing a silane monomer and generating a siloxane bond by a condensation reaction. Examples of the silane monomer include a silane compound (1) having a polymerizable double bond and a hydrolyzable group and / or a condensable group, no polymerizable double bond, and a hydrolyzable group and / or Examples thereof include a silane compound (2) having a condensable group, and a silane compound (3) having a polymerizable double bond and not having a hydrolyzable group and / or a condensable group may coexist.

  The silane compound (1) is preferably represented by, for example, the following general formula (1).

(R ¹ ) _m (R ² ) _n SiX _4-mn (1)
[In General Formula (1), R ¹ represents an organic group having a polymerizable double bond.
R ² represents at least one group selected from the group consisting of an alkyl group, an aryl group, and an aralkyl group, and may have a substituent that does not contain a polymerizable double bond.
X represents a hydrolyzable group and / or a condensable group.
m represents an integer from 1 to 3, and n represents an integer from 0 to 2. However, m + n is 3 or less. ]

In the general formula (1), R ² preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and still more preferably 1 to 3 carbon atoms. R ² is preferably an alkyl group, and particularly preferably a methyl group.

  In the general formula (1), X is preferably one group selected from the group consisting of a hydroxyl group, an alkoxy group, and an alkylcarbonyloxy group.

  The alkoxy group for X is preferably a linear or branched alkoxy group having 1 to 5 carbon atoms, more preferably a linear or branched alkoxy group having 1 to 4 carbon atoms, particularly preferably. Is a methoxy group or an ethoxy group. Further, the alkylcarbonyloxy group of X preferably has 2 to 5 carbon atoms, more preferably 2 to 3 carbon atoms, and particularly preferably an acyloxy group.

In the general formula (1), R ¹ is preferably a group represented by the following general formula (a).
R ³ -L ^1- * (a)
[In General Formula (a), R ³ represents a vinyl group or an isopropenyl group,
L ¹ represents a single bond or a divalent organic group having 1 to 18 carbon atoms which may have a substituent.
* Represents a bond with a silicon atom. ]

In general formula (a), the organic group represented by L ¹ is preferably a linear or branched divalent aliphatic hydrocarbon group or a divalent aromatic hydrocarbon group. It is more preferably a branched alkylene group or a divalent aromatic hydrocarbon group, more preferably a linear alkylene group or a divalent aromatic hydrocarbon group, and a linear alkylene Particularly preferred is a group. The organic group of L ¹ is more preferably 1 to 15 carbon atoms, more preferably 4 to 12 carbon atoms. The methylene group in L ¹ may be replaced with a carbonyl group or an oxygen atom, and the hydrogen atom on L ¹ may be substituted with an alkoxy group having 1 to 10 carbon atoms.

Specifically, R ¹ is more preferably an organic group represented by the following general formulas (a1) to (a3).
^{_{CH 2 = C (-R 4)}} -COO-L 2 - * (a1)
^{_{CH 2 = C (-R 5)}} - * (a2)
^{_{CH 2 = C (-R 6)}} -L 3 - * (a3)
[In General Formula (a1), R ⁴ represents a hydrogen atom or a methyl group, L ² represents an optionally substituted divalent organic group having 1 to 20 carbon atoms, and * represents a silicon atom. Represents the bond hand.
In general formula (a2), R ⁵ represents a hydrogen atom or a methyl group, and * represents a bond with a silicon atom.
In the general formula (a3), R ⁶ represents a hydrogen atom or a methyl group, L ³ represents a divalent organic group having 1 to 20 carbon atoms that may have a substituent, and * the silicon atom Represents a bond. ]

In general formula (a1), the organic group of L ² is preferably a linear or branched divalent aliphatic hydrocarbon group, and is preferably a linear or branched alkylene group. More preferably, it is a linear alkylene group. The organic group of L ² is more preferably from 1 to 10 carbon atoms, more preferably 2-5 carbon atoms. The hydrogen atom on L ² may be substituted with an alkoxy group having 1 to 10 carbon atoms. More preferably, the alkoxy group substituting for the hydrogen atom of L ² has 1 to 5 carbon atoms.

Examples of the organic group represented by the general formula (a1) include a (meth) acryloxypropyl group. Examples of the silane compound (1) when R ¹ is represented by the general formula (a1) include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyltrimethoxysilane, γ -Acryloxypropyltriethoxysilane, γ-methacryloxypropyltriacetoxysilane, γ-methacryloxyethoxypropyltrimethoxysilane (also referred to as γ-trimethoxysilylpropyl-β-methacryloxyethyl ether), γ-methacryloxy Examples include propylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, and γ-acryloxypropylmethyldimethoxysilane. These may be used alone or in combination of two or more.

Examples of the organic group represented by the general formula (a2) include a vinyl group and an isopropenyl group. As the silane compound (1) when R ¹ is represented by the general formula (a2), vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriacetoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, vinylmethyl And diacetoxysilane. These may be used alone or in combination of two or more.

In general formula (a3), the organic group represented by L ³ is preferably a linear or branched divalent aliphatic hydrocarbon group or a divalent aromatic hydrocarbon group. It is preferably a branched alkylene group or a divalent aromatic hydrocarbon group, more preferably a linear alkylene group or a divalent aromatic hydrocarbon group, and a linear alkylene Particularly preferred is a group. Organic group L ³ is, more preferably 1 to 15 carbon atoms, more preferably 4 to 12 carbon atoms. The methylene group in L ¹ may be replaced with a carbonyl group or an oxygen atom.

Examples of the organic group represented by the general formula (a3) include an alkenyl group, a vinylphenyl group, an isoalkenyl group, an isopropenylphenyl group, and a vinyloxycarbonyl group. Examples of the silane compound (1) when R ¹ is represented by the general formula (a3) include 5-hexenyltrimethoxysilane, 5-hexenyltriethoxysilane, 7-octenyltrimethoxysilane, and 9-deceni Examples include rutrimethoxysilane, γ-trimethoxysilylpropyl vinyl ether, ω-trimethoxysilylundecanoic acid vinyl ester, p-trimethoxysilylstyrene, 5-hexenylmethyldimethoxysilane, and 5-hexenylmethyldiethoxysilane. These may be used alone or in combination of two or more.

Among these, R ¹ is preferably a group represented by the general formula (a3).

  Examples of the silane compound (2) include tetrafunctional silane monomers such as tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, and tetrabutoxysilane; methyltrimethoxysilane, methyltriethoxysilane, and ethyltrisilane. Trifunctional silane monomers such as ethoxysilane; epoxy such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane Di- or trialkoxysilanes having a group; di- or trialkoxysilanes having an amino group such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane; dialkylsilanes such as dimethyldimethoxysilane, dimethyldiethoxysilane, etc. Bifunctional Silane monomer; trimethyl methoxy silane, trialkyl silane such as trimethyl ethoxy silane.

  Examples of the silane compound (3) include silane compounds having two or more vinyl groups such as dimethyldivinylsilane, methyltrivinylsilane, and tetravinylsilane.

  When the organic-inorganic composite component is formed from a silane monomer and a vinyl monomer, the amount of the vinyl monomer used is preferably 1 part by mass or more, more preferably 5 parts by mass with respect to 100 parts by mass of the silane monomer. Part or more, more preferably 7 parts by weight or more, preferably 5000 parts by weight or less, more preferably 4000 parts by weight or less, and still more preferably 3000 parts by weight or less.

  As a method for producing the above-mentioned particles (organic particles) containing various organic components, emulsion polymerization, suspension polymerization, dispersion polymerization, seed polymerization, sol-gel seed polymerization, and the like can be appropriately employed. From the viewpoint of reducing the particle size distribution, seed polymerization or sol-gel seed polymerization is preferred. The sol-gel seed polymerization method is an embodiment of seed polymerization, and particularly means that seed particles are synthesized by the sol-gel method. For example, the case where polysiloxane obtained by the hydrolytic condensation reaction of the silane compounds (1) and (2) is used as seed particles is exemplified. Therefore, the seed polymerization includes a case where the seed particles are made of an organic material and a case where the seed particles are made of a material in which an organic material and an inorganic material are combined (in the case of a sol-gel seed polymerization method). For example, when the organic particles have a vinyl polymer skeleton and a polysiloxane skeleton, the production method includes adding a silane compound (1) having a polymerizable group, a hydrolyzable group and / or a condensable group. A method is preferably employed in which polymerized polysiloxane particles are prepared by decomposing and condensing, and then the above-mentioned vinyl monomer or the like is absorbed into the polymerizable polysiloxane particles for polymerization.

  The organic particles may be colorless and transparent, white, or colored.

  The organic particles used in the present invention preferably do not contain a metal element, but may contain a metal element as long as the characteristics as the organic particles are not impaired. The content of the metal element is preferably 100000 ppm (mass basis) or less, more preferably 20000 ppm (mass basis) or less, further preferably 500 ppm (mass basis) or less, particularly preferably 100 ppm (mass basis) in the organic particles. )

The organic particles used in the present invention preferably have a true density of less than 2.5 g / cm ³ , more preferably 2.3 g / cm ³ or less, and even more preferably 1.8 g / cm ³ or less. When the true density is small, the dispersibility is good even when the composite particles are mixed with a solvent or a resin component. Although the minimum of the density of organic particles is not specifically limited, For example, it is 0.9 g / cm < ³ >.

  As an inorganic material which comprises the said inorganic particle, an inorganic pigment or a clay mineral is preferable.

  Examples of the inorganic pigment include titanium dioxide, zinc white, bengara, chromium oxide, iron black, cobalt blue, alumina white, iron oxide yellow, viridian, yellow lead, zinc chromate, strontium chromate, white carbon, ultramarine blue, calcium carbonate, lead. Oxide inorganic pigments such as white; sulfide inorganic pigments such as zinc sulfide, cadmium yellow, vermilion and cadmium red; sulfate inorganic pigments such as lithopone, molybdate orange and precipitated barium; cyanide compounds such as bitumen Inorganic pigments; Margaret violet; Carbon-based inorganic pigments such as carbon black; and the like can be used.

  Examples of the clay mineral include talc, pyrophyllite, smectite (saponite, hectorite, saconite, stevensite, montmorillonite, beidellite, nontronite, etc.), vermiculite, mica (phlogopite, biotite, chinwald mica, muscovite, Paragonite, ceradonite, sea chlorite, etc.), chlorite (clinochlore, chamosite, nimite, penantite, sudite, dombasite, etc.), brittle mica (clinintite, margarite, etc.), sulite, serpentine (antigolite, lizardite) , Chrysotile, amethyite, chronsteadite, burcherin, greenerite, garnierite, etc.), kaolin (kaolinite, dickite, nacrite, halloysite, etc.), etc. It can be used two or more.

  The metal particles are composed of a metal such as a simple metal or an alloy, and specific examples of the metal element contained include alkali metals such as lithium, sodium, potassium, rubidium, and cesium; beryllium, magnesium, Alkaline earth metals such as calcium and strontium; Group 4 transition metals such as titanium and zirconium; Group 6 transition metals such as chromium, molybdenum and tungsten; Group 7 transition metals such as manganese; Iron, ruthenium and osmium Group 8 transition metals, Group 9 transition metals such as cobalt and rhodium, Group 10 transition metals such as nickel, palladium and platinum, Group 11 transition metals such as copper, silver and gold, and Group 12 transition metals such as zinc, cadmium and the like Group 13 typical metals such as group typical metals, aluminum and indium, Group 14 typical metals such as tin and lead, antimony, bismuth, etc. Group 15 typical metal include metalloids such as silicon. Among these metals, specific examples of the alloy containing two or more metal elements include brass, bronze, alumel, invar, and constantan.

Examples of the metal compound constituting the metal compound particles include metal oxides, metal hydroxides, metal nitrides, metal sulfates, metal carbonates, metal silicates, metal sulfides, and the like. Hydrates of compounds may also be used. Of these, metal oxides and metal nitrides are preferable.
Furthermore, the metal compound (including hydrate) is not limited to a single product, and may be a mixture containing a metal compound. In this case, inorganic pigments and minerals (particularly clay minerals) can be used in combination with the metal compound. Examples of the metal contained in these compounds include transition metals (fourth period transition metals such as titanium, chromium, manganese, iron, cobalt, nickel, copper; zirconium, niobium, molybdenum, ruthenium, rhodium, palladium, silver, etc. 5th period transition metals: tantalum, tungsten, osmium, platinum, gold, mercury, etc. 6th period transition metals), typical metals (aluminum; zinc; cadmium, indium, tin, etc. 5th period typical metals; mercury, 6th periodic typical metals such as lead and bismuth), alkali metals (lithium, sodium, potassium, rubidium, cesium, etc.), alkaline earth metals (beryllium, magnesium, calcium, strontium, barium, etc.), metalloids (silicon, Antimony, etc.).

Specifically, indium oxide (In ₂ O ₃ ), zinc oxide (ZnO), and tin oxide (SnO) are preferably used as the metal oxide. These metal oxides are preferably doped with other elements. The doping amount of other elements is preferably 0.1% by mass or more and 10% by mass or less, for example. Examples of the other elements include Group 3 elements such as scandium and yttrium; Group 4 elements such as titanium, zirconium and hafnium; Group 5 elements such as vanadium, niobium and tantalum; Group 6 elements such as molybdenum and tungsten. Group 12 elements such as zinc; Group 13 elements such as boron, aluminum, gallium and indium; Group 14 elements such as silicon, germanium and tin; Group 15 elements such as antimony; Group 16 elements such as tellurium; Group 17 elements such as fluorine; and the like.

Among them, indium oxide (In ₂ O ₃ ) is a group 17 element such as fluorine; a group 4 element such as titanium, zirconium or hafnium; a group 5 element of niobium or the like; a group 5 element of tantalum; a group 6 element such as molybdenum or tungsten. It is preferable that the element is doped with a Group 12 element such as zinc; a Group 14 element such as tin or germanium; or a Group 16 element such as tellurium.
Zinc oxide (ZnO) is a group 3 element such as yttrium and scandium; a group 4 element such as titanium, zirconium and hafnium; a group 5 element such as vanadium; a group 13 element such as boron, indium, aluminum and gallium. Preferably doped with a Group 14 element such as silicon or germanium; a Group 17 element such as fluorine;
The tin oxide (SnO) is preferably doped with a Group 12 element such as zinc; a Group 13 element such as aluminum or indium; a Group 15 element such as antimony;

  As the inorganic nitride, silicon nitride, aluminum nitride, boron nitride, titanium nitride, zirconium nitride, tantalum nitride, niobium nitride, or the like can be used, and one or more of these can be used.

The average particle size d _c of the core particles is preferably 80nm or more, more preferably 100nm or more, more preferably 150nm or more, and preferably at 100μm or less, more preferably 60μm or less, more preferably Is 40 μm or less, particularly preferably 30 μm or less. The average particle size d _c of the core particles can be measured with calipers method, or Coulter counter method described later in Example. When the particles are not spherical, the average particle diameter is the diameter of a circle having a projected area equal to the projected area of the particles (2 × (projected area / π) ^0.5 ).
The particle shape is not particularly limited, but may be a spherical shape, a flat shape, a plate shape, a needle shape, a rod shape, a conical shape, or the like.

  In the production method of the present invention, examples of the adhesive resin (adhesive resin solid content) used in the first composition together with the core particles and the solvent described later include a thermoplastic resin or a heat or photocurable resin. Thermal or photocurable resins are preferred. Examples of the thermoplastic resin include styrene resins such as polystyrene and styrene-acrylic acid ester copolymers; (meth) acrylic resins such as polymethyl methacrylate; olefin resins such as polyethylene; polyester resins such as polyester; Plastic polyurethane; thermoplastic epoxy resin; and the like. The resin used in the present invention is soluble (for example, room temperature (25 ° C.) in a low boiling point solvent (for example, boiling point of 100 ° C. or less) from the viewpoint of improving the surface coverage of the organic core particles during the production of composite particles. And a solubility of 1% by mass or more).

  Examples of the thermosetting resin include epoxy resin, phenol resin, cyanate ester resin, melamine resin, polyimide resin, bismaleimide resin, urea resin, alkyd resin silicone resin, vinyl ester resin, benzoxazine resin, urethane resin ( A (meth) acrylic resin or the like can be used, and an epoxy resin is preferable.

  As the epoxy resin, glycidyl ether such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenyl epoxy resin, triphenylmethane type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, etc. Type epoxy resin; glycidyl amine type epoxy resin; glycidyl ester type epoxy resin; olefin oxidation type epoxy resin such as alicyclic epoxy resin; hindered type epoxy resin; etc., and these epoxy resins are halogenated Also good. Examples of the glycidyl ether type epoxy resin include compounds in which glycidyl ether is substituted on the hydroxy group of diols such as polyethylene glycol, polypropylene glycol, butanediol, hexanediol, and cyclohexanedimethanol (hereinafter referred to as “low molecular weight epoxy compound”). The glycidyl ether-type epoxy resin formed in (5) may also be preferably used. Moreover, as an epoxy resin, the epoxy resin which can be diluted with a low molecular weight epoxy compound and the diluted mixture becomes comparatively low viscosity (for example, 50 Pa * s or less) is preferable.

  Silicone resin means a polymer having a siloxane bond by hydrolysis of a silane compound. Examples of the silane compound used as a raw material for the silicone resin include tetraethoxysilane, tetramethoxysilane, methyltriethoxysilane, and dimethyldiethoxysilane. , Phenyltriethoxysilane, diphenyldiethoxysilane, methyltrimethoxysilane, dimethyldimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, ethyltriethoxysilane, propyltriethoxysilane, butyltriethoxysilane, isobutyltrimethoxysilane, hexyl Alkoxysilanes such as triethoxysilane, octyltriethoxysilane and decyltriethoxysilane; trifluoropropyltrimethoxysilane, tridecaful Fluoroalkylsilanes such as looctyltrimethoxysilane, heptadecafluorodecyltrimethoxysilane, trifluoropropyltriethoxysilane, heptadecafluorodecyltriethoxysilane and tridecafluorooctyltriethoxysilane; vinyltrimethoxysilane, vinyltriethoxy Silane, γ-aminopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, N- (β-aminoethyl) -γ-amino And silane coupling agents such as propyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, and γ-chloropropyltrimethoxysilane; Specific examples of the silicone resin include polysiloxanes such as dimethylpolysiloxane, methylhydrogenpolysiloxane, and methylphenylpolysiloxane; some of the side chains of the polysiloxane are long-chain alkyl groups, ether chains, fluoroalkyl groups, Organopolysiloxanes such as modified polysiloxanes modified with aralkyl groups, amino groups, epoxy groups, mercapto groups, carboxy groups, and the like.

  The photocurable resin is not particularly limited, and a conventionally known photocurable resin can be used. For example, a polyester resin; a urethane (meth) acrylic resin, an epoxy (meth) acrylic resin, or the like. ) Acrylic resin; Polyvinyl carbonate resin such as polyvinyl acetate resin; Among these, photocurable (meth) acrylic resins such as urethane (meth) acrylic resins and epoxy (meth) acrylic resins are preferable.

  Examples of dicarboxylic acids used in the photocurable polyester resin include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid; oxalic acid, succinic acid, glutaric acid, adipic acid, suberic acid, And aliphatic dicarboxylic acids such as sebacic acid and dodecanoic acid. Examples of the diols include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,4-cyclohexanedimethanol.

  Examples of the (meth) acrylate monomer used in the photocurable (meth) acrylic resin include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, tert- Monofunctional (meth) acrylic monomers such as butyl (meth) acrylate; bifunctional (meth) acrylic monomers such as polyethylene glycol di (meth) acrylate, trimethylolpropane di (meth) acrylate, and polypropylene glycol di (meth) acrylate Trimethylolpropane tri (meth) acrylate, dimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxytri (meth) acrylate, trimethylolpropane proxy tri (meth) acrylate, trimethylol group Trifunctional (meth) acrylic monomers such as panethylene glycol adduct triacrylate, tetramethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate; tetramethylolmethane tetra (meth) acrylate, tetramethylolpropane tetra (meth) ) Acrylic monomers, tetrafunctional (meth) acrylic monomers such as pentaerythritol tetra (meth) acrylate; pentafunctional (meth) acrylic monomers such as dipentaerythritol penta (meth) acrylate 6 such as dipentaerythritol hexa (meth) acrylate Functional (meth) acrylic monomers; (meth) acrylic monomers having a carbamoyl group such as carbamoyloxy (meth) acrylate and carbamoyloxyethyl (meth) acrylate Mer; it can be used like; glycidyl (meth) having an epoxy group such as acrylate (meth) acrylic monomer; having a hydroxy group such as hydroxyethyl (meth) acrylate (meth) acrylic monomer. The urethane bond can be formed by reacting a (meth) acrylic monomer having a hydroxy group with an isocyanate compound such as butyl isocyanate.

In addition, as the vinyl carboxylate used in the photocurable vinyl carbonate resin,
Vinyl acetate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate,
Examples include vinyl caprate and vinyl laurate.

  In the first composition, the content of the adhesive resin (adhesive resin solid content) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass with respect to 100 parts by mass of the core particles. Part or more, more preferably 1.2 parts by weight or more, preferably 20 parts by weight or less, more preferably 12 parts by weight or less, and still more preferably 8 parts by weight or less.

When a heat or photocurable resin is used as the adhesive resin (adhesive resin solid content), the first composition preferably further contains a curing agent. As such a curing agent, a heat curing agent in which a reaction with a curable group of the curable resin is accelerated by heat; a photocuring agent that absorbs light and activates it can be preferably used. From the viewpoint of improving the coating property of the resin layer on the surface of the organic core particles, these curing agents have a solubility in an organic solvent (for example, a solubility of 1% or more at room temperature (25 ° C.)). Is preferred.
Moreover, when preparing the preliminary composition which increased the amount of solvent beforehand when preparing a 1st composition, it is preferable to include a hardening | curing agent in a preliminary composition.

  As said thermosetting agent, a conventionally well-known thermosetting agent can be used, For example, an amine compound, organic acid dihydrazine, a phosphorus compound, a phenol resin, an acid anhydride, an imidazole type hardening | curing agent etc. can be used. From the viewpoint of curing temperature, curing speed, and adhesive strength, an imidazole curing agent or an amine compound is preferable.

  More specifically, the photocuring agent may be any compound that has an absorption band at the wavelength of the active energy ray and generates a starting species for the curing (polymerization) reaction. As the active energy ray, ultraviolet rays (wavelength: 300 to 450 nm) can be preferably used from the viewpoint of running cost. As the photocuring agent, there are many kinds and high reactivity with respect to the monomer, and therefore a radical reaction initiator and a cationic polymerization initiator can be preferably used.

Examples of the radical reaction initiator include benzoin ether initiators such as benzoin and 2,2-dimethoxy-1,2-diphenylethane-1-one; acetophenone, 2-hydroxy-2-methyl-1-phenyl- Propan-1-one, 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- [4- [4- ( 2-hydroxy-2-methyl-propionyl) -benzyl] phenyl] -2-methyl-propan-1-one and other hydroxyalkylphenone initiators, 2-methyl-1- (4-methylthiophenyl) -2-morpholino Propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2- (dimethylamino) -2- [ Alkylphenone initiators such as aminoalkylphenone initiators such as (4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone; benzophenone, 4-benzoyl-4′- Benzophenone initiators such as methyldiphenyl sulfide, 1-hydroxy-cyclohexyl-phenyl-ketone; 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diisopropylthioxanthone Thioxanthone initiators such as 1,2-octanedione, 1- [4- (phenylthio)-, 2- (O-benzoyloxime), ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyl Oxime ester initiators such as oxime); quinone initiators such as 2-methylanthraquinone; xanthone initiators such as 2,4-diisopropylxanthone; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis ( And 2,4,6-trimethylbenzoyl) -acylphosphine oxide initiators such as phenylphosphine oxide; Among these, alkylphenone initiators are preferable, and hydroxyalkylphenone initiators are more preferable.
As the cationic polymerization initiator, an aromatic sulfonium salt-based initiator is preferable.

  When a curing agent is used, the amount of the curing agent used is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass with respect to 100 parts by mass of the adhesive resin (adhesive resin solid content). Part or more, more preferably 0.1 part by weight or more. The amount of the curing agent used is preferably 7 parts by mass or less, more preferably 5 parts by mass or less, and still more preferably 4 parts by mass with respect to 100 parts by mass of the adhesive resin (adhesive resin solid content). It is as follows.

  In the production method of the present invention, when preparing the first composition, the solvent used to disperse the core particles and the adhesive resin (adhesive resin solid content) is preferably an organic solvent, and the first composition From the viewpoint of easy adjustment of the solvent content, the boiling point is preferably 100 ° C. or lower. The boiling point of the solvent is more preferably 90 ° C. or less, and further preferably 80 ° C. or less. Moreover, it is preferable that the boiling point of a solvent is 40 degreeC or more, More preferably, it is 50 degreeC or more, More preferably, it is 60 degreeC or more.

  Examples of the organic solvent include alcohol solvents such as ethanol, propanol, isopropyl alcohol, sec-butyl alcohol, and tert-butyl alcohol; ether solvents such as 1,2-dimethoxyethane, diisopropyl ether, ethyl acetate, and tetrahydrofuran; Ketone solvents such as methyl ethyl ketone; alkyl halide solvents such as carbon tetrachloride, chloroform and 1,2-dichloroethane; aromatic solvents such as benzene, alkane solvents such as cyclohexane, hexane and heptane; nitriles such as acetonitrile Solvent; amine solvents such as triethylamine; and the like. Among these, ketone solvents and alkyl halide solvents are preferable.

  In the production method of the present invention, the first composition containing the above core particles, adhesive resin (adhesive resin solids), solvent, and the like are mixed with the child particles having a particle diameter smaller than that of the core particles. The child particles used here are not particularly limited, and conventionally known materials (organic materials, inorganic materials, metals, metal compounds) can be used. In detail, the same materials as those used for the core particles are used. Can be used.

Daughter particles are those smaller than the core particles, an average particle diameter d _f, for example is preferably 5nm or more, more preferably 10nm or more, still more preferably 20nm or more. The larger average particle diameter d _f of the daughter particles, the properties of the daughter particles (e.g. electrical characteristics, hydrophilicity, etc.) can be imparted more effectively composite particle surface, thereby forming a larger irregularity (protruding portion) it can. Further, the average particle diameter d _f of the daughter particles, preferably at 20μm or less, more preferably 8μm or less, more preferably 6μm or less. If the average particle diameter d _f of the daughter particles is in this range, can more remarkably suppress the desorption of the child particles, (Electrical characteristics of the daughter particles, hydrophilicity, etc.) surface properties of the composite particles and the composite particle surface The unevenness can be maintained stably.
When the particles are not spherical, the average particle diameter is the diameter of a circle having a projected area equal to the projected area of the particles (2 × (projected area / π) ^0.5 ).

In the production method of the present invention, the bond between the core particle and the core particle in a weakly wet state is made into a composite particle by utilizing the fact that the bond between the child particle and the core particle or between the child particle and the child particle is weaker. From such a viewpoint, the ratio (d _f / d _c ) of the average particle diameter d _f of the child particles and the average particle diameter d _c of the core particles is preferably 0.2 or less, more preferably It is 0.15 or less, More preferably, it is 0.13 or less, It is preferable that it is 0.01 or more, More preferably, it is 0.02 or more, More preferably, it is 0.03 or more.

2. Composite Particles Composite particles obtained by the above production method are core particles, a resin layer covering the core particles, and present in the resin layer or on the resin layer surface, and are fixed by the resin layer. The composite particles are also included in the technical scope of the present invention. The form of immobilization of the child particles includes a form in which a part of the child particles are present in the resin layer and a part is exposed and immobilized. For example, as shown in FIG. 1 (a), the composite particle 4 of the present invention may be one in which the entire surface of the core particle 1 covered with the resin layer 2 is covered with the child particle 3. As shown in FIG. 1B, a part of the surface of the core particle 1 covered with the resin layer 2 may be covered with the child particle 3, and further, as shown in FIG. The core particles 1 covered with the resin layer 2 may be covered while the particles 3 overlap each other in the thickness direction. The existence form of the child particles can be confirmed, for example, by observing the cross section of the composite particle with a scanning transmission electron microscope (STEM).

  In the present invention, the term “immobilization” means a state in which desorption of child particles is suppressed, and preferably does not include ionic bonds or covalent bonds, and particularly preferably does not include covalent bonds. In addition, the suppression of the detachment of the child particles is, for example, that there is no difference in the immobilized state of the child particles even when they are stirred with a paint shaker (manufactured by Toyo Seiki Seisakusho, product name: test disperser). Not). The immobilized state of the composite particles can be observed with a scanning electron microscope (SEM).

  The composite particles obtained by the production method of the present invention preferably have an average particle size of 85 nm or more, more preferably 110 nm or more, and further preferably 170 nm or more. The average particle size of the composite particles is 150 μm or less, more preferably 105 μm or less, and still more preferably 68 μm or less. The average particle diameter of the composite particles can be measured by the caliper method described later in the examples or the Coulter counter method.

  Furthermore, the composite particles obtained by the production method of the present invention are suppressed from agglomeration, which is obtained by comparing the volume average particle diameter of the composite particles with the sum of the volume average particle diameters of the core particles and the child particles. I can confirm. For example, the ratio of the volume average particle diameter of the composite particles to the sum of the volume average particle diameters of the core particles and the child particles (composite particle diameter / (core particle diameter + child particle diameter)) is, for example, 3 or less, preferably 2 It can be said that aggregation is suppressed when it is 0.5 or less, more preferably 2 or less, and particularly preferably 1.5 or less. The ratio (composite particle diameter / (core particle diameter + child particle diameter)) is usually 1 or more.

Further, in the present invention, it is possible to firmly fix the child particles while thinning the resin layer of the composite particles to exhibit the core particle characteristics and the surface characteristics of the child particles. The thickness t _r of the resin layer in this case, is preferably 5nm or more, more preferably 8nm or more, preferably 10μm or less, more preferably 8μm or less, more preferably is 5μm or less . The thickness of the resin layer can be obtained, for example, by selecting a portion of the resin layer where the child particles do not enter or contact in the scanning electron microscope image of the composite particle cross section and measuring the thickness thereof. it can.

The ratio of the average particle diameter d _f of the thickness t _r and the child particles of the resin layer (t _r / d _f) is preferably 0.5 or less, more preferably 0.4 or less, 0 .1 or more, more preferably 0.2 or more, still more preferably 0.3 or more.

  The composite particles of the present invention are those in which the detachment of the child particles is remarkably suppressed. Electronic component-related materials, film-related materials, resin molding-related materials, paint-related materials, optical-related materials, medical-related materials, printing-related materials It can be usefully used in the fields of materials, information recording related materials, information communication related materials, construction related materials and the like. Specifically, it is suitable for an anti-blocking agent, an anti-glare agent, a matting agent, a fluidity improving agent, a tactile sensation improving agent, a base material for conductive fine particles, a cosmetic, a base material for a bio-inspection agent, and the like.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. Of course, it is possible to implement them, and they are all included in the technical scope of the present invention. In the following, “part” means “part by mass” and “%” means “mass%” unless otherwise specified.

<Measurement of average particle diameter>
[Caliper method]
When measuring the particle diameter of less than 1 μm and the pearl pigment, it was measured by a caliper method.
SEM photographs were taken so that the total number of particles was around 200, and the diameter of 100 particles randomly selected from the photograph (maximum length of photographed particles (cross section)) was measured with calipers. The arithmetic average diameter was calculated as the average particle diameter.
[Coulter counter method]
When measuring a particle diameter of 1 μm or more, the volume average particle diameter measured using a Coulter counter particle size distribution measuring device [manufactured by Beckman Coulter, Inc., product number: MultiSizer4] is displayed.

[Confirmation of free fine particles]
The number of free fine particles present on the sample surface was confirmed from a composite particle SEM photograph at a magnification at which fine particles could be confirmed and the surface of the sample surface could be confirmed.

[Flowability index of powder (first composition and composite particles)]
Using a powder tester PT-X type (manufactured by Hosokawa Micron Corporation), the following four items (repose angle, degree of compression, spatula angle, and uniformity or cohesion) are measured, and the following conversion table (Table 1, Hayashi) Based on Tsunemi's “Powder Technology Pocket Book” Industrial Research Committee, November 1, 1996), the angle of repose, the degree of compression, the spatula angle, and the index of uniformity or cohesion were calculated. The total value was taken as the liquidity index.

[Observation of particles and measurement of resin layer thickness]
When the particle size of the composite particles is less than 100 μm, use a scanning electron microscope (“FE-SEM S-4800” (equipped with a cold cathode field emission electron gun)) as a measuring device. Acceleration voltage 20 kV, emission current 10 μA, W.V. D. = 8 mm, condenser lens 5 conditions, observation was made on the adhesion state of the fine particles in the composite particles, the aggregation state of the composite particles, and the amount of fine particles that were not attached to the composite particles and released.
Further, when the particle diameter of the composite particles is 100 μm or more, an optical microscope (“Digital Microscope VHX-1000” manufactured by Keyence Corporation) is used as a measuring device, and the adhesion state of the fine particles on the composite particles and the aggregation of the composite particles The state and the amount of fine particles free from adhering to the composite particles were observed.
In addition, the thickness of the resin layer used the scanning transmission electron microscope (Hitachi High Technology Co., Ltd. "HD-2700"). In the case of observation with a scanning transmission electron microscope, the composite particles were embedded in an epoxy resin, and a section having a thickness of 100 nm was prepared with a microtome. When there was not much difference between the atomic weights of the elements contained in the resin particles and the fine particles, dyeing was performed with osmium tetroxide (OsO ₄ ). The average thickness of the resin layer was measured based on the photographed scanning transmission electron microscope image.

[Particle peeling evaluation]
20 parts of composite particles and comparative composite particles, 30 parts of methanol, 200 parts of 1 mmφ zirconia beads are charged into a 250 ml mayonnaise bottle, and 3 hours with a paint shaker (manufactured by Toyo Seiki Seisakusho, product name: test disperser (paint shaker)) Stir. 20 parts of the composite particle dispersion was taken out and diluted with 100 parts of methanol, and then allowed to stand to precipitate the composite particles. After this dilution and sedimentation were repeated twice, the taken out composite particles were dried for 24 hours in a dryer at 50 ° C. The obtained composite particles were observed with a scanning electron microscope, and the peeling state of the fine particles was compared with the particles before the bead dispersion treatment and evaluated according to the following criteria.
A: Almost no separation of fine particles is observed.
◯: About 80% remains, with slight separation of fine particles observed.
Δ: About half of the fine particles are peeled off.
X: Most fine particles are peeled off.

[Evaluation of fine particle peeling of pearl pigment]
The pearl pigment is obtained by coating the surface of the lamellar mica particles with titanium dioxide. Since the pearl pigment itself is pulverized by the above evaluation method because of the thin lamellar particles, only the pearl pigment was evaluated under the following conditions.
10 parts of the pearl pigment composite particles were placed in 20 parts of methanol, and subjected to ultrasonic irradiation for 10 minutes with an ultrasonic cleaner (trade name BRANSON 5210, manufactured by Yamato Kagaku Co., Ltd.). The composite particles were taken out, further diluted with 100 parts of methanol and settled, and the taken out composite particles were dried in a dryer at 50 ° C. for 24 hours. The obtained composite particles were observed with a scanning electron microscope, and the peeling state of the fine particles was compared with the particles before the bead dispersion treatment and evaluated according to the following criteria.
A: Almost no separation of fine particles is observed.
◯: About 80% remains, with slight separation of fine particles observed.
Δ: About half of the fine particles are peeled off.
X: Most fine particles are peeled off.

Synthesis example 1
(Preparation of organic particle No. 1)
A solution obtained by mixing 250 parts of water and 5 parts of 25% aqueous ammonia was put into a four-necked flask equipped with a condenser, a thermometer, and a dripping port, and 78 parts of γ-methacryloxypropyltrimethoxysilane was stirred into this solution. A solution in which 125 parts of methanol and methanol were mixed was added from a dripping port, and γ-methacryloxypropyltrimethoxysilane was hydrolyzed and condensed to prepare seed particles. One hour after the start of the reaction, 250 parts of water was added from the dropping port, and the reaction was carried out for 2 hours. When the particle size of the seed particles in the obtained emulsion (seed particle dispersion) was measured, the average particle size was 5.1 μm.
After further stirring for 30 minutes, 6.5 parts of an anionic emulsifier (LA-10, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), 610 parts of water, 610 parts of cyclohexyl methacrylate, 2,2′-azobis (2,4-dimethylvalero) Nitrile) (trade name V-65, manufactured by Wako Pure Chemical Industries, Ltd.) (4.3 parts) was mixed and emulsified and dispersed for 5 minutes using a homogenizer to prepare an emulsion. This emulsion was added to the seed particle dispersion and further stirred for 30 minutes. As a result of observing the seed particles after the monomer absorption with a microscope, it was confirmed that the particle diameter was larger than that before addition of the monomer emulsion, and the seed particles absorbed the monomer. One hour after the addition of the monomer emulsion, 1 kg of water was added to the seed particle dispersion, the temperature was raised to 75 ° C. under a nitrogen atmosphere, and the temperature was maintained at 75 ° C. for 3 hours to perform radical polymerization.
The emulsion thus obtained is subjected to solid-liquid separation by natural sedimentation (decantation), the obtained cake is washed with methanol, and further dried under vacuum at 120 ° C. for 2 hours to obtain organic particles (1). Obtained. The results of measuring the particle size of the organic particles (1) are shown in Table 2.

Synthesis example 2
(Preparation of organic particle No. 2)
A flask equipped with a paddle stirring blade, an inert gas introduction tube, a reflux condenser, and a thermometer was charged with 300 parts of a deionized aqueous solution in which 3 parts of polyvinyl alcohol (Kuraray Poval 205, manufactured by Kuraray Co., Ltd.) was dissolved. A monomer solution in which 75 parts of styrene, 25 parts of divinylbenzene, 2 parts of 2,2′-azobis (2,4-dimethylvaleronitrile) and 1 part of thiosalicylic acid (TSA) were dissolved was charged. Thereafter, while stirring at 700 rpm, the reaction was carried out at 65 ° C. for 3 hours, and further, the reaction was carried out at 70 ° C. for 2 hours to complete the polymerization reaction. The reaction solution was cooled and filtered, and the resulting polymerization product was dried with a hot air dryer at 80 ° C. for 3 hours to obtain organic particles (2). Table 2 shows the results of measuring the particle diameter of the obtained organic particles (2).

Synthesis example 3
(Preparation of organic fine particles)
To a stainless steel reaction kettle equipped with a stirrer, a thermometer, and a cooler, 820 parts of deionized water and 5 parts of sodium dodecylbenzenesulfonate were added, and the internal temperature was raised to 75 ° C. and kept at the same temperature. On the other hand, 140 parts of methyl methacrylate (hereinafter referred to as “MMA”) and 60 parts of divinylbenzene (81% by weight of active ingredient; hereinafter referred to as “DVB”) are mixed in a container different from the above reaction vessel. 200 parts of the monomer composition was prepared.
After replacing the inside of the reaction kettle with nitrogen gas, 20 parts of the monomer composition (10% of the total amount of the monomer composition), 50 parts of 0.4% hydrogen peroxide solution, and 0.4% L- 50 parts of ascorbic acid aqueous solution was added into the reaction kettle to carry out an initial polymerization reaction. Next, 180 parts of the remainder of the monomer composition (90% of the total amount of the monomer composition), 450 parts of 0.4 wt% hydrogen peroxide water, and 450 parts of 0.4% L-ascorbic acid aqueous solution, It was dripped uniformly into the reaction kettle over 6 hours from different charging ports. Thereafter, the internal temperature was raised to 90 ° C. and held at the same temperature for 6 hours for aging to obtain a resin fine particle dispersion. These resin fine particle dispersions were dried using a spray dryer (product name Palvis GB22 manufactured by Yamato Kagaku Co., Ltd.) to obtain organic particles (3). The results of measuring the particle size of the organic particles (3) are shown in Table 2.

Example 1
A stainless steel container with a capacity of 21 L has a main blade that stirs the entire powder, a chopper blade that crushes the powder, a thermometer, a nozzle that supplies a resin liquid in the vicinity of the chopper blade, and small particles. The core particles shown in Table 2 are charged into a powder mixer equipped with an input port, an exhaust port for discharging shaft seal air and solvent vapor, and an exhaust port for discharging mixed powder, and the rotational speed of the main blade is 150 rpm. The core particles were stirred at a chopper blade rotational speed of 3000 rpm.
Next, the resin mixture shown in Table 2 was added from the nozzle in 5 minutes while the core particles were being stirred. The mixture was stirred and mixed for 20 minutes. The powder temperature was 26 ° C.
Table 2 shows the results of once stopping stirring, sampling the powder, and measuring the fluidity index. Fine particles shown in Table 2 were introduced from the inlet, and further stirred for 30 minutes under the same conditions, and the mixed powder was taken out from the outlet. The mixed powder was a powder having good fluidity. This mixed powder was put into a stainless steel vat, dried and heat-treated for 2 hours with a 120 ° C. drier to cure the epoxy resin, and composite particle no. 1 was obtained. Thus obtained composite particle No. Table 2 shows the particle diameter of No. 1, the thickness of the resin layer, the results of observation with a scanning electron microscope (SEM), the fluidity index, and the fine particle peeling evaluation.

Example 2
The core particles shown in Table 2 were charged into a mixer (manufactured by Kawata, product name: Supermixer SMV20B (capacity 20 L)), and the core particles were stirred at a blade rotation speed of 1200 rpm.
Next, the resin mixture shown in Table 2 was added from the nozzle in 5 minutes while the core particles were being stirred. The mixture was stirred and mixed for 30 minutes. The powder temperature was 28 ° C.
Table 2 shows the results of once stopping stirring, sampling the powder, and measuring the fluidity index. The child particles shown in Table 2 were introduced from the inlet, and the mixture was stirred for 2.5 hours while flowing warm water of 50 ° C. through the jacket of the mixer to evaporate the solvent. Thereafter, the mixture was cooled and the mixed powder was taken out from the outlet. The mixed powder was a powder having good fluidity. This mixed powder was spread thinly and uniformly and irradiated with ultraviolet rays using a 0.2 J / cm ² high pressure mercury lamp to sufficiently cure the photocurable resin. 2 was obtained. The obtained composite particle No. Table 2 shows the particle diameter of No. 2, the thickness of the resin layer observed with a scanning electron microscope (SEM), the fluidity index, and the results of the fine particle peeling evaluation.

Example 3
The powder particles used in Example 1 were charged with the core particles shown in Table 2, and the core particles were stirred at a main blade rotation speed of 185 rpm and a chopper blade rotation speed of 2000 rpm. Next, the resin mixture shown in Table 2 was added from the nozzle in 25 minutes while the core particles were being stirred. The amount of shaft seal air of the chopper blade was increased, and stirring was performed for 3 hours under the same conditions to evaporate the solvent and discharge it from the machine. The powder temperature was 28 ° C.
Table 2 shows the results of once stopping stirring, sampling the powder, and measuring the fluidity index. The child particles shown in Table 2 were introduced from the inlet and further stirred for 30 minutes. Thereafter, steam was passed through the jacket, and the powder temperature was heated to 120 ° C. and maintained for 2 hours to perform heat treatment to cure the epoxy resin. Thereafter, the mixture is cooled, the mixed powder is taken out from the outlet, and the composite particle No. 3 was obtained. The composite particles were very fluid powders. The obtained composite particle No. Table 2 shows the particle diameter of No. 3, the thickness of the resin layer, the results of observation with a scanning electron microscope (SEM), the fluidity index, and the fine particle peeling evaluation.

Example 4
The core particles shown in Table 2 were charged into the powder mixing apparatus used in Example 2, and the core particles were stirred at a blade rotation speed of 1200 rpm.
Next, with the core particles being stirred, the resin mixture shown in Table 2 was added from the nozzle in 5 minutes, and stirring and mixing were carried out for 40 minutes. The powder temperature was 27 ° C.
Table 2 shows the results of once stopping stirring, sampling the powder, and measuring the fluidity index. The child particles shown in Table 2 were introduced from the inlet, and the mixture was stirred for 2 hours while flowing warm water at 80 ° C. through the jacket of the mixer to evaporate the water. Further, after stirring for 60 minutes, the mixed powder was taken out from the discharge port, and the composite particle no. 4 was obtained. The composite particles were very fluid powders. The obtained composite particle No. No. 4 was a powder having very good fluidity. This composite particle No. Table 2 shows the particle diameter of No. 4, the thickness of the resin layer, the optical microscope observation results, the fluidity index, and the results of the fine particle peeling evaluation.

Comparative Example 1
In a 100 ml sample bottle, 30 parts of core particles shown in Table 3 and 6 parts of child particles shown in Table 3 were added and mixed uniformly. The entire amount of the premixed powder was put into a surface treatment apparatus (product name: Hybridization System Model 0, manufactured by Nara Machinery Co., Ltd.) using impact force, and the surface treatment operation was performed for 3 minutes at a rotating disk peripheral speed of 80 m / s. The composite particles were taken out from the discharge port, and the composite particle No. 1 was obtained.
This comparative composite particle No. 1 was a powder with good fluidity. The obtained comparative composite particle No. Table 3 shows the particle diameter of 1, the thickness of the resin layer, the observation result of the scanning electron microscope (SEM), the fluidity index, and the evaluation result of the fine particle peeling.

Comparative Example 2
The same operation as in Example 1 was performed except that the resin mixed solution as shown in Table 3 was used as the resin mixed solution, and the child particles as shown in Table 3 were used. 2 was obtained. This comparative composite particle No. The fluidity of No. 2 was a very bad powder. The obtained comparative composite particle No. Table 3 shows the particle diameter of 2, the thickness of the resin layer, the scanning electron microscope (SEM) observation results, the fluidity index, and the results of the fine particle peeling evaluation.

Comparative Example 3
The same operation as in Example 1 was performed except that the resin mixed solution as shown in Table 3 was used as the resin mixed solution, and the child particles as shown in Table 3 were used. 3 was obtained. This comparative composite particle No. The fluidity of No. 3 was a relatively good powder. The obtained comparative composite particle No. Table 3 shows the particle diameter of No. 3, the thickness of the resin layer, the scanning electron microscope (SEM) observation results, the fluidity index, and the results of the fine particle peeling evaluation.

Comparative Example 4
In a 3000 mL four-necked flask equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen introduction tube, a surfactant (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name “Hitenol (registered trademark) N-08”) After charging 1200 g of an aqueous solution containing 3.2 g, a monomer solution in which 2 parts of lauryl peroxide (LPO) and 1 part of thiosalicylic acid (TSA) were dissolved in 320 parts of styrene was added. K. The mixture was stirred for 5 minutes at 5000 rpm with a homomixer (manufactured by Primix Co., Ltd.) to obtain a uniform suspension, and 150 parts of deionized water was further added. Next, while blowing nitrogen gas into the flask, the temperature was raised to 75 ° C. and heated for 2 hours, and further heated at 90 ° C. for 2 hours to advance the styrene polymerization reaction. The resulting solid was filtered off and washed thoroughly with water. The results of measuring the volume average particle diameter of the obtained organic particles (4) are shown in Table 3 described later.
Next, the obtained organic particles (4) were added to 1200 g of ion exchange water and 4 g of polyvinyl alcohol (PVA: manufactured by Kuraray Co., Ltd., trade name “Kuraray Poval (registered trademark) PVA-205”). It was made to disperse | distribute to a flask and it was set as the uniform dispersion liquid. Thereafter, 40 g of child particle colloidal silica (manufactured by Nissan Chemical Industries, Ltd., trade name “Snowtex (registered trademark) ZL”, solid content 40%, average particle size 80 nm) was added. A liquid containing 1 (polystyrene: PS), child particles (colloidal silica), and a water-soluble polymer (polyvinyl alcohol) was obtained. To this liquid, 10 g of a 10% sulfuric acid aqueous solution and 36 g of a glutaraldehyde solution were added and further heated at 80 ° C. for 2 hours. The obtained solid content was separated by filtration, sufficiently washed with water, and dried at 80 ° C. for 6 hours. After drying, the solid material was crushed with a small pulverizer, and composite particle No. 1 for comparison was used. 300 g of 4 was obtained.

  In Tables 2 and 3, “Pearl Glaze ME-100R” means a pearl pigment (“Pearl Glaze ME-100R” manufactured by Nihon Koken Co., Ltd.), and wet copper powder Cu1400Y represents copper particles (“Mitsui Metal Mining Co., Ltd.” Wet copper powder Cu1400Y "), Celoxide 2021P means epoxy resin (" Celoxide 2021P "manufactured by Daicel Corporation), and styrene butadiene resin refers to styrene-butadiene emulsion (" Nalstar SR- "manufactured by Nippon I & L Co., Ltd.). 116 "), sun aid SI-80L means a curing agent (" Sun aid SI-80L "manufactured by Sanshin Chemical Co., Ltd.), and DAROCUR 1173 means a polymerization initiator (" DAROCUR 1173 "manufactured by Ciba). , Eposter S is a spherical amino resin particle powder (Nippon Shokubai "Eposter S") Taste, and SEAHOSTER P100 means spherical silica particles powder (manufactured by Nippon Shokubai Co., Ltd. "Seahostar P100"), Snowtex ZL means colloidal silica (manufactured by Nissan Chemical Industries, Ltd. "SNOWTEX ZL").

  According to the production method of the present invention, composite particles can be easily obtained regardless of the types of core particles and child particles. The resulting composite particles are those in which the detachment of fine particles is remarkably suppressed. Electronic component-related materials, film-related materials, resin molding-related materials, paint-related materials, optical-related materials, printing-related materials, information recording-related It can be usefully used for applications such as materials, sensor-related materials, information and communication-related materials, and building-related materials. Specifically, it is suitable for an antenna member, an inductor member, a wireless power feeding member, metal toner, a heat dissipation material, and the like.

1 Core particle 2 Resin layer 3 Child particle 4 Composite particle

Claims (5)

Preparing a first composition comprising core particles, a resin, and a solvent, having a solvent content of 0.5% by mass or more and a fluidity index of 35 or more;
The manufacturing method of the composite particle which mixes this 1st composition and the child particle whose particle diameter is smaller than the said core particle.   The manufacturing method according to claim 1 whose solvent content in said 1st composition is 30 mass% or less. 3. The production method according to claim 1, wherein a ratio (d _f / d _c ) of an average particle diameter d _f of the child particles and an average particle diameter d _c of the core particles is 0.2 or less. The added amount of the child particles is calculated by the following formula: Calculated child particle added amount (W ₂ ) = core particle specific surface area (S) × core particle weight (W ₁ ) / child particle ratio projected area (A)
The manufacturing method according to any one of claims 1 to 3, which is 0.4 times or more and 1.2 times or less of a calculated particle addition amount (W ₂ ) obtained in step ( ₁ ).   The said resin is a manufacturing method in any one of Claims 1-4 containing a heat | fever or photocurable resin.