JP3097710B2 - Epoxy resin powder containing inorganic particles - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inorganic substance in which the particle size can be controlled over a wide range, the content of inorganic particles is high, and the surface of the granular substance whose surface properties are controlled is coated with a resin. The present invention relates to an inorganic resin particle-containing epoxy resin powder composed of particle-containing epoxy resin particles.

[0002]

2. Description of the Related Art The main uses of an epoxy resin particulate powder containing inorganic particles according to the present invention are as follows: a material powder for an electrostatic latent image developer such as a magnetic carrier, a magnetic toner and conductive magnetic particles; an electromagnetic wave absorbing material; Electromagnetic wave shielding material powder, rubber, plastic coloring material, filler and reinforcing material and paint,
Coloring materials for paints and adhesives, matting materials, fillers, reinforcing materials, and the like.

[0003] In recent years, as a material having a high performance and a novel function, composites between different kinds of materials have been actively performed, and one of the composites is a composite granular material (hereinafter, referred to as an inorganic particle and an organic polymer). Various researches and developments have been made on composite particles, and these have been put to practical use.

In the case where magnetic particles are used as inorganic particles, these composite particles are mainly composed of a magnetic carrier,
When color pigment particles are used as inorganic particles as material powder for an electrostatic latent image developer such as a magnetic toner and a conductive magnetic powder, rubber, plastic, paint, paint and an adhesive colorant are mainly used. Used as a matting agent.

[0005] In any of the above fields, the characteristics required of the composite granules in common are that the particle size can be selected from a wide range so that the composite granules having a desired size can be selected according to the application. In particular, the composite can be controlled over a range of 1 to 1000 μm, the content of the inorganic particles is as high as possible so that various properties and functions of the inorganic particles can be sufficiently exhibited, That is, the surface properties of the granular material can be controlled.

[0006] First, regarding the average particle size of the composite granules, a conventional carrier material powder is disclosed in
No. 282563, “{the carrier particle size is appropriately set to an average particle size of 20 to 400 μm} from the viewpoint of the balance between the developer life and the adhesion of the photoreceptor carrier and the image quality.” As described, the composite particulate matter of about 20 to 400 μm is used as a magnetic toner material powder,
Japanese Patent Application Laid-Open No. 1-172972 states that "If the average particle size of the toner exceeds 25 μm, the replenishing property is poor and the image is blurred. If the average particle diameter is less than 5 μm, the cleaning property and the transfer property deteriorate." As described above, composite granules having a size of about 5 to 25 μm are known as conductive magnetic powders as disclosed in
JP-A-142540, "The volume average particle diameter of the conductive magnetic particles is 1/5 to that of the magnetic toner (about 5 to 25 m).
As described in the description "preferably about 4/5", composite particulate matter of about 1 to 20 µm is required.

[0007] Regarding the content of inorganic particles contained in the composite granules, see JP-A-60-188419.
Another disadvantage of the emulsion polymerization method and the suspension polymerization method is that particles generally cannot contain a large amount of inorganic or organic particles. Particularly, it is difficult to compound a large amount of inorganic particles having a high specific gravity. It has been desired that such particles be realized. "

Next, the surface physical properties of the composite granular material will be described. The resin used in the vehicle or the resin composition varies depending on the application, but it is strongly required that the composite particulate matter be easily adapted to the type of the resin used.

In the field of material powder for an electrostatic latent image developer, the toner is required to have an appropriate charge amount suitable for a developing device in order to form a clear image. In order to impart a desired charge amount to a carrier, it is strongly required that the charge amount of a carrier having a role of giving a charge can be freely controlled as desired.

This fact is described in Japanese Patent Application Laid-Open No. 60-458, "The role of the carrier during development is as follows: (1) The toner is provided with accurate triboelectric charging characteristics and an appropriate charge, and the toner adhering to the image area is again And removing the toner by electrostatic attraction to form a clear image. "

Conventionally, organic polymers are roughly classified into thermoplastic resins such as vinyl-based, styrene-based, and acrylic-based resins, phenol-based resins, and melamine-based resins.
Although thermosetting resins such as epoxy resins are known,
As a resin for producing composite granules, a thermoplastic resin that is easily granulated is generally used, and granulation is difficult, and in particular, a thermosetting resin that is difficult to obtain spherical particles has not been used. .

On the other hand, thermosetting resins are more excellent in durability, impact resistance and heat resistance than thermoplastic resins. Therefore, a composite comprising inorganic particles and a thermosetting resin taking advantage of these advantages is used. Granules are strongly required.

Conventionally, as a method for obtaining a composite comprising inorganic particles and a thermosetting resin, a method comprising pulverizing a composite comprising inorganic particles, an epoxy resin and a phenol resin acting as a curing agent (Japanese Patent Laid-Open No. 58-1983). As a method of granulating an epoxy resin, a method of preparing an uncured epoxy emulsion with the aid of an emulsifier and curing the uncured epoxy emulsion with a curing agent (Japanese Patent Laid-Open No. JP-A-53-73249) is known. Furthermore, as a method for producing a composite particulate material comprising inorganic or organic particles and an epoxy resin, an uncured epoxy emulsion is prepared with the aid of an emulsifier in the presence of inorganic or organic particles, and a water-soluble amine compound is prepared. A method of curing with a curing agent (JP-A-60-188419) is known.

[0014]

A composite comprising inorganic particles and an epoxy resin, the particle size of which can be controlled over a wide range, the content of the inorganic particles is as high as possible, and the surface properties are controlled. Granules are the most demanded at present, but such composite granules have not yet been obtained by the above-mentioned conventional method.

That is, according to the method described in the above-mentioned JP-A-58-122705, although the content of inorganic particles is high, granulation is difficult.

In the case of the method described in the above-mentioned Japanese Patent Application Laid-Open No. 60-188419, the particle size of the composite particles is about 0.5 to 100 μm, and the composite particles exceeding 100 μm are obtained. This is difficult, and the content of the inorganic or organic particles is at most about 75% by weight, and the content is limited.

Further, since the cured epoxy resin particles are produced in the presence of 5% by weight, preferably 10% by weight or more of an emulsifier with respect to the resin, the possibility that the emulsifier is contained is very high. As a result, the charge amount of the composite particulate matter is liable to fluctuate, which causes a problem in product quality.

Therefore, the present invention comprises inorganic particles and an epoxy resin, the particle size can be controlled over a wide range, the content of the inorganic particles is as high as possible, and the surface properties are controlled. It is a technical object to obtain composite granules without using an emulsifier or the like.

[0019]

The above technical objects can be achieved by the present invention as described below.

That is, the present invention comprises inorganic particles whose surface has been subjected to lipophilic treatment and a cured epoxy resin, has a number average particle diameter of 1 to 1000 μm, and has a content of the inorganic particles of 80 to 1000 μm. This is an epoxy resin particulate powder containing inorganic particles, wherein the surface of the particulate material of the composite particulate material is 99% by weight and is coated with a resin.

Next, various conditions for implementing the present invention will be described.

The particulate composite according to the present invention is obtained by reacting and curing bisphenols and epihalohydrin in an alkaline aqueous medium or curing an uncured epoxy resin in an aqueous medium in the presence of inorganic particles. In producing a composite granular material composed of inorganic particles and a cured epoxy resin, the composite particles can be obtained by using, as the inorganic particles, inorganic particles having a surface subjected to lipophilic treatment.

The inorganic particles in the present invention may be those which do not dissolve in water or are not altered or denatured by water. For example, magnetite particles ( FeO x.
Fe ₂ O ₃ (0 <x ≦ 1)), maghemite particles, particles coated with or containing cobalt, hematite particles, hydrous ferric oxide particles, barium or strontium
Ferrite particles as well as manganese, nickel, including the Umm,
Iron oxide particles such as spinel type ferrite particles containing one or more metals selected from zinc and the like, titanium oxide particles, silica particles, talc particles, alumina particles, barium sulfate particles, barium carbonate particles, cadmium yellow Particles, calcium carbonate particles, zinc white particles and the like can be used.

The inorganic particles may be in any form such as a cube, a polyhedron, a sphere, a needle, a plate, and the like. As long as it is smaller than the average particle size of the product, it can be used, but 0.01 to 5.0 μm, especially 0.1 to 5.0 μm.
Those having a range of 2.0 μm are preferred.

In the present invention, the inorganic particles whose surfaces are subjected to lipophilic treatment may be prepared by simply mixing the inorganic particles and the lipophilic agent or by mixing the inorganic particles and the lipophilic agent in an aqueous solvent. Then, it can be obtained by any method such as a method of adsorbing a lipophilic treatment agent on the particle surface.

As the lipophilic treatment agent, titanate-based or silane-based coupling agents having a lipophilic group, silylating agents, silicone oils and the like can be used.
In particular, those having a functional group reactive with the epoxy resin (-NH _2, Formula 1, etc.) are preferable because an effect of such increase the strength of the composite granules themselves.

[0027]

Embedded image

Examples of titanate coupling agents having a lipophilic group include isopropyl triisostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris (dioctyl pyrophosphate) titanate, bis (dioctyl pyrophosphate) oxyacetate titanate, bis ( Dioctyl pyrophosphate) ethylene titanate and the like, as silane coupling agents having a lipophilic group, include N-β (aminoethyl) γ-aminopropyl trimethoxysilane, N-
β (aminoethyl) γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N
-Phenyl-γ-aminopropyltrimethoxysilane,
γ-glycidoxypropylmethyldiethoxysilane, β
-(3,4 epoxycyclohexyl) ethyltrimethoxysilane (the above is a silane coupling agent having a functional group capable of reacting with an epoxy resin), vinyltrichlorosilane, vinyltriethoxysilane, vinyltris (β-methoxy Examples of the silylating agent include hexamethyldisilazane, trialkylalkoxysilane, and trimethylethoxysilane. Examples of the silicone oil include dimethyl silicone oil and methyl hydrogen silicone oil.

The amount of treatment with the lipophilic treatment agent is 0.1 to 5.0% by weight based on the weight of the inorganic particles. If the amount is less than 0.1% by weight, the lipophilic treatment is insufficient, so that it is not possible to obtain a composite particulate material having a high content of the inorganic particles intended in the present invention. If the content exceeds 5.0% by weight, the degree of lipophilicity is too large, and the adhesive strength of the generated composite granules increases, causing aggregation of the composite granules to occur. Therefore, it is difficult to control the particle size of the composite granular material.

As the bisphenols in the present invention, compounds having two or more phenolic hydrogen groups such as bisphenol A, bisphenol F, bisphenol S, resorcin and the like can be used. Bisphenol A is preferred in terms of economy.

The amount of the bisphenol used is 0.5 to 25% by weight based on the weight of the inorganic particles. If the amount is less than 0.5% by weight, the amount of the epoxy resin to be produced is insufficient for the inorganic particles, so that it is difficult to obtain composite granules. If the amount exceeds 25% by weight, the amount of the epoxy resin to be formed becomes excessive with respect to the inorganic particles, and it is not possible to obtain a composite particulate having a high content of the inorganic particles intended for the present invention. In addition, aggregation of the composite particulates tends to occur, which makes it difficult to control the particle size of the composite particulates.

As the epihalohydrin in the present invention, epichlorohydrin, epibromohydrin, epiiodohydrin and the like can be used, and epichlorohydrin is preferable.

The amount of epihalohydrin used is 0.3 to 20% by weight based on the weight of the inorganic particles. If the amount is less than 0.3% by weight, the amount of the epoxy resin to be produced is insufficient for the inorganic particles, so that it is difficult to obtain composite granules. If the amount exceeds 20% by weight, the amount of the epoxy resin to be produced becomes excessive with respect to the inorganic particles, and it is not possible to obtain a composite granular material having a high content of the inorganic particles intended for the present invention. In addition, aggregation of the composite particulates tends to occur, which makes it difficult to control the particle size of the composite particulates.

The bisphenols and epihalohydrin used in the present invention are used in a molar ratio of 0.5 to 1.0:
1.0. If it is less than 0.5, granulation becomes difficult due to the influence of reaction by-products and the like caused by excess epihalohydrin. If it exceeds 1.0, the curing speed will be high, and it will be difficult to obtain composite granules, and even if obtained, the particle size distribution will be widened.

The alkaline aqueous medium in the present invention can be obtained by adding an alkali such as sodium hydroxide or potassium hydroxide to water.

The reaction in the present invention is carried out by stirring an alkaline aqueous medium containing inorganic particles, bisphenols and epihalohydrin at 60 to 90 ° C. while stirring in the presence of a curing agent.
The polymerization is allowed to proceed for about 1 to 5 hours by heating to a temperature in the range of 1 to 5 or while stirring in an aqueous medium containing inorganic particles and an uncured epoxy resin in the presence of a curing agent.
This is carried out by raising the temperature to a temperature in the range of ℃ 90 ° C. and allowing the curing reaction to proceed for about 1 to 8 hours.

As the curing agent , for example, acid anhydrides and amines, which are widely known as curing agents for epoxy resins, can be used.

As the uncured epoxy resin, epoxy compounds having two or more epoxy groups in a molecule such as glycidyl ether at both ends of bisphenol A and glycidyl ether at both ends of polyethylene glycol can be used.

In the present invention, the composite particulate matter formed in the alkaline aqueous medium or the aqueous medium may be subjected to solid-liquid separation by a usual method such as filtration, centrifugation, etc., followed by aqueous drying after heating.

As the composite granules used for coating with the resin, any of those which have been dried in vacuum, those which have been dried under normal pressure, and those which have been wet immediately after filtration can be used.

The resin for coating the surface of the composite particles is selected from well-known epoxy resins, polyester resins, styrene resins, melamine resins, acrylonitrile polymers, polyamide resins, silicon resins and fluorine resins. One or more resins can be used,
Mainly by changing the type of resin or improve the familiarity with the vehicle and resin composition of the composite particulate matter,
Surface physical properties can be controlled, for example, by changing the charge amount.

The coating amount of the resin is 0.1 to the composite granular material.
When the content is not less than 05% by weight and less than 0.05% by weight, the coating tends to be insufficient and non-uniform, and it is difficult to improve the familiarity and to control the charge amount as desired. . On the other hand, if the coating amount is too large, the content of the ferromagnetic fine particles in the composite granules decreases, and a large magnetization value cannot be obtained. Preferably it is 0.1 to 10% by weight.

The method of coating the composite particles with the resin may be carried out by a known method, for example, the following method. The coating with the melamine resin is carried out by reacting the composite particles with the melamines and aldehydes in a neutral or weakly basic aqueous medium with stirring, followed by gelation. Gelation may be performed in the presence of an acidic catalyst, if necessary. The gelled product is cured by heat treatment. The temperature at that time is 130-150 ° C
Is preferred.

Since the ultrafine melamine resin can uniformly and densely cover the surface of the composite granule, the electrical resistance of the composite granule can be effectively improved. In addition, since the melamine resin in the form of ultrafine particles is coated, the specific surface area is large, and effective high electric resistance is easily obtained.

Examples of the melamines include melamine and formaldehyde adducts of melamine, such as dimethylol melamine, trimethylol melamine, hexamethylol melamine, and an initial condensate of melamine / formaldehyde, of which melamine is most preferred. .

An example of a coating reaction with a melamine resin in the production method of the present invention will be described below. While stirring the aqueous medium vigorously, melamines, aldehydes and complex particulates are added at room temperature to adjust the solution pH to 7 to 9.5, and then to 0.5 to 1.5 ° C / min, preferably while stirring. Is 0.
The temperature is raised to 70 to 90 ° C, preferably 80 to 85 ° C at a rate of 8 to 1.2 ° C / min, and the reaction is performed at this temperature for 10 to 30 minutes, preferably 15 to 20 minutes.

Next, the content is cooled to 30 ° C. or less, and an acidic catalyst is added. Then, the temperature is gradually increased with stirring, and the reaction temperature is 75 to 95 ° C., preferably 80 to 90 ° C. and 60 to 90 ° C. The reaction is carried out for 150 minutes, preferably for 80 to 110 minutes. In such a reaction, a gelling reaction proceeds simultaneously with the reaction, and the melamine resin is coated on the particle surface. After reacting and coating in this way, the reaction product is cooled to 30 ° C. or lower, whereby an aqueous dispersion of a composite particulate material whose particle surface is coated with ultrafine melamine resin is obtained.

Next, this dispersion is separated into solid and liquid by a conventional method such as filtration and centrifugation, and then washed.
When the ultrafine melamine resin is cured by heat treatment at a temperature of 0 to 150 ° C., a composite granule whose surface is uniformly coated with the ultrafine cured melamine resin is obtained.

Next, the coating with the acrylonitrile polymer is carried out by stirring and polymerizing the composite particles and the monomer containing acrylonitrile as a main component in a weakly acidic aqueous medium under an inert gas atmosphere. . As the polymerization proceeds, the monomer containing acrylonitrile as a main component precipitates on the surface of the composite granular material as ultrafine particles or a film-like substance insoluble in water. Since it can be uniformly and densely coated, the electrical resistance of the composite particles can be effectively improved.

As the monomer, acrylonitrile or a mixture of acrylonitrile and another vinyl monomer can be used. The vinyl monomer used in addition to acrylonitrile is not particularly limited. For example, styrene compounds such as styrene, divinylbenzene, vinyltoluene 4-bromostyrene, methyl methacrylate, methyl acrylate, acrylic acid, ethylene glycol dimethacrylate , 2-hydroxyethyl methacrylate and the like can be used.

The acidic catalyst optionally used in the production method of the present invention includes mineral acids such as sulfuric acid and hydrochloric acid, formic acid,
Phosphoric acid, oxalic acid and the like; The amount of the acidic catalyst used is preferably such that the pH of the reaction initiation system is maintained at 5 to 6.

The reaction between the composite granules and the monomer containing acrylonitrile as a main component in the present invention is carried out in an atmosphere of an inert gas such as nitrogen or argon and is carried out at room temperature to 70 ° C.
Proceed at a temperature in the range The inert gas is necessary for the purpose of removing oxygen that hinders the progress of the polymerization reaction. At a temperature lower than room temperature, the speed of the polymerization reaction is low and the efficiency is low. 7
At a temperature of 0 ° C. or higher, the polymerization reaction rate is too high to obtain a uniform film. Also, the amount of water charged is not particularly limited,
It is desirable that the composite particulate matter be 30 to 60% by weight.

An example of the coating reaction between the composite granules and the monomer containing acrylonitrile as a main component in the present invention will be described below. Under a stream of nitrogen, the composite granules are dispersed in an aqueous medium, and an acrylonitrile-based monomer and an acid catalyst are added.
Heat to 35 ° C. and stir for 5-15 minutes. An aqueous solution of potassium persulfate and sodium sulfite is gradually added thereto, and the mixture is reacted at the same temperature for 1 to 3 hours. In such a reaction, an acrylonitrile polymer is coated on the particle surface simultaneously with the reaction. After reaction coating in this manner, the reactants were
When cooled to 0 ° C., an aqueous dispersion of composite particulates whose particle surfaces are coated with an acrylonitrile-based polymer is obtained.

Next , this dispersion is subjected to solid-liquid separation according to a conventional method such as filtration or centrifugation, and then washed,
When the acrylonitrile-based polymer is melted by heat treatment at a temperature of 120 ° C., a composite granule whose surface is uniformly covered with the acrylonitrile-based polymer film is obtained.

In the present invention, the coating with the polyamide is
A well-known anion polymerization method can be used. That is, the composite granules are suspended in a polyamide polymerization solution comprising the composite granules and a lactam and a solvent for the lactam and an anionic polymerization catalyst, and an activator is added under stirring to form an anion of the lactam. This is carried out by initiating the polymerization and producing a polyamide by ring-opening polymerization of lactams.

The polyamide formed by the progress of the polymerization reaction can uniformly and densely cover the entire surface of the composite granule, so that the electrical resistance of the composite granule can be efficiently improved, and Great mechanical strength can be obtained.

Examples of the lactam include all lactams producing polyamides, for example, caprolactam, enantholactam, capryllactam, lauryl lactam and the like. Of these, caprolactam is most preferred. The lactam is preferably used in an amount of 0.5 to 40% by weight, particularly preferably 5 to 40% by weight, based on the composite granules.
３０30% by weight. When the amount is less than 0.5% by weight, the coating amount may be insufficient. On the other hand, when the amount is more than 40% by weight, the polyamide resin is formed alone and is difficult to separate from the composite granules. It may be.

The solvents used are halogenated or non-halogenated aliphatic hydrocarbons having a boiling point in the range from 80 to 200 ° C., for example paraffinic or cycloaliphatic or aromatic (for example xylene or Toluene). The solvent must dissolve the lactam but not the composite granules and must not react with any of the catalysts, activators, lactams or composite granules used in the method of the present invention.

The catalyst includes sodium or a compound thereof, for example, sodium hydride or sodium methylate, and is preferably sodium hydride.

Examples of the activator include lactam N-carboxyanilide, isocyanate, carbodiimide, cyanimide, acyllactam, triazine, urea, N-substituted imide, ester and the like.

The coating reaction with the polyamide resin is carried out in an organic solvent. In this case, the amount of the solvent to be charged is not particularly limited, but it is desirable that the concentration of the composite particles be 10 to 50% by weight.

An example of the coating reaction of the polyamide in the present invention will be described below. The solvent, the composite granules, and the lactam are added in this order at room temperature under a nitrogen atmosphere, and the temperature is increased at a rate of 0.5 to 10 ° C./min, preferably 2 to 6 ° C./min with gentle stirring. ~ 150 ° C, preferably 10
The temperature is raised to 0 to 120 ° C., and maintained at this temperature for 30 to 120 minutes, preferably 45 to 75 minutes to dissolve all lactams and distill off 5 to 30% of the solvent used to remove the lactam. Distillable water is distilled off by azeotropic distillation. Then return to the atmosphere, add the catalyst, and stir 9
Heating to 0-150 ° C, preferably 100-130 ° C,
The activator previously dissolved in the solvent is
After the addition for 4 hours, preferably 1.5 to 3 hours, the reaction temperature is 90 to 150 ° C., preferably 100 to 130 ° C. for 1 hour.
The reaction is performed for 0 to 90 minutes, preferably for 20 to 60 minutes.
By this reaction, the polyamide is uniformly coated on the particle surface. After reacting and coating in this way, the reactant is
Upon cooling to below ° C, a solvent dispersion of the composite granules with the granules surface coated with polyamide is obtained.

Next, the dispersion is subjected to solid-liquid separation by a conventional method such as filtration and centrifugation, washed with a solvent, and the obtained composite granules are dried at a temperature of 80 to 100 ° C. Furthermore, after neutralizing the alkali catalyst residue with an aqueous solution of a weak acid such as phosphoric acid and solid-liquid separation, the mixture is dried again at a temperature of 80 to 100 ° C. to obtain a composite granular material whose surface is uniformly coated with a polyamide layer. can get.

The coating with an epoxy resin, a polyester resin, a styrene resin, a silicon resin and a fluorine resin may be performed, for example, by spraying the resin onto the composite particles using a spray drier, using a Henschel mixer, a high speed mixer, or the like. Any method such as a method of dry-mixing the composite granular material and the resin and a method of impregnating the composite granular material in a solvent containing the resin may be used.

As the epoxy resin, bisphenol A
As a polyester resin, a polyester resin obtained by condensation polymerization of a polyol such as ethylene glycol or triethylene glycol and a dicarboxylic acid, for example, maleic acid or itaconic acid, may be styrene. Examples of the system resin include styrene-acryl copolymers such as polystyrene and styrene-butyl acrylate, styrene-butadiene copolymer, and styrene-maleic anhydride copolymer, and examples of the silicon resin include a heat-curable silicone resin and room temperature. A silicone resin such as a curable silicone resin, a silicone oil, a silane coupling agent, or the like can be used. As the fluorine resin, a fluorine-containing resin such as polytetrafluoroethylene, polyvinylidene fluoride, or a tetrafluoroethylene-ethylene copolymer can be used. That.

[0066]

First, the most important point in the present invention is that the surface is composed of inorganic particles whose surface has been subjected to lipophilic treatment and a cured epoxy resin, and has a number average particle diameter of 1 to 1000 μm. The epoxy resin granules containing the inorganic particles in which the surface of the composite granules having the content of 80 to 99% by weight is coated with the resin can control the particle size over a wide range, and the content of the inorganic particles is reduced. It is high and the physical properties of the surface are controlled.

In the present invention, the particle size of the composite particles is determined by the concentration of the solids in the raw material charged in the production of the composite particles, the ratio of the epoxy resin component to the inorganic particles, the degree of lipophilicity of the surface of the inorganic particles, and the like. And the larger these values are, the larger the particle size of the formed composite particulate material tends to be.

In the present invention, the reason why a composite particulate material having a high content of inorganic particles can be obtained is as follows.
As shown in a comparative example to be described later, when the particle surface of the inorganic particles is not lipophilized, the content of the inorganic particles is limited, so that the particle surface of the inorganic particles is lipophilized. I believe it is due to

The reason why the emulsifier need not be used in the present invention is that the present inventors have made the surface of the inorganic particles lipophilic so that the uncured epoxy resin, which is the initial product of the reaction, and the inorganic particles are separated. It is believed that this is because the properties of the resulting composite are very easily emulsified.

In the present invention, if the type of resin coated on the surface of the granular material of the composite particles is the same as the type of the resin in the vehicle or the resin composition, the surface of the composite granular material will become familiar. It is more improved, and the charge amount can be freely controlled depending on the type of resin.

In the present invention, since the content of the inorganic particles contained in the composite granule is high, a large number of irregularities are formed on the surface of the composite granule. The resin coated on the surface of the granular material is firmly adhered,
It is difficult to peel off due to mechanical stress such as impact and friction.

[0072]

Next, the present invention will be described with reference to examples and comparative examples. The number average particle diameter in the following Examples and Comparative Examples is indicated by a value measured by a laser diffraction type particle size distribution meter (manufactured by Horiba Seisakusho Co., Ltd.). Electron microscope S-800 (Co., Ltd.)
(Manufactured by Hitachi, Ltd.). The saturation magnetization was measured using a vibrating sample magnetometer VSM-3S-15 (Toei Kogyo Co., Ltd.)
The values were measured under an external magnetic field of 10 KOe. The content of the inorganic particles in the composite granule is represented by a value obtained by measuring the true specific gravity of the composite granule using a multivolume densitometer (manufactured by Micrometics) and calculating from the magnitude of this specific gravity. Was. The electric resistance was indicated by a value measured by "High Resistance Meter 4329A" (manufactured by Yokogawa Hewlett-Packard Company).

The toner charge amount of the composite particles whose particle surfaces are coated with resin is 95 parts by weight of the composite particles and a commercially available toner CLC-200 black (trade name).
200 mg of a mixture with 5 parts by weight (manufactured by Canon Inc.) was obtained from a value A (μc) measured using a blow-off charge amount measuring machine Model TB-200 (manufactured by Toshiba Chemical Co., Ltd.). .2 × 0.05 (μc / g)].

<Production of Composite Granules> Examples 1 to 17 Comparative Examples 1 and 2 Example 1 In a 500 ml four-necked flask, water 50 ml, sodium hydroxide 5.50 g, bisphenol A 20 g, epichlorohydrin 10 g, anhydrous 2.0 g of phthalic acid and 0.5% by weight of the particle surface of a silane coupling agent KBM602
200 g of magnetite particles (average particle diameter 0.24 μm) coated with (Shin-Etsu Chemical Co., Ltd.) were charged and stirred. After the temperature was raised to 80 ° C. at a rate of 1.0 to 1.5 ° C./min, stirring was continued at the same temperature for 1.5 hours to produce composite granules. Next, after filtering off the contents in the flask, washing with water and drying were performed to obtain composite granules. The obtained composite granular material had a number average particle size of 36.6 μm, and FIG.
As shown in the scanning electron micrograph (× 1500) shown in FIG. Further, as shown in the scanning electron micrograph (× 12000) of FIG. 2, it was confirmed that the surface of the composite granular material had a large number of uniform irregularities in the unit of the contained inorganic particles. Further, the content of the magnetite particles was 86.6% by weight, and the saturation magnetization was 73.6 emu / g.

Examples 2 to 17, Comparative Examples 1 and 2 Except that the type of inorganic particles, the amount of bisphenol, the amount of epichlorohydrin, the amount of sodium hydroxide, the type and amount of the curing agent, and the amount of water were varied. In the same manner as in Example 1, composite particulate matter was produced. Examples 2 and 1
According to each example of No. 7, composite granules B to Q were obtained. As a result of observation with a scanning electron microscope, each of the obtained composite particulates B to Q had many irregularities formed on the surface. The composite granules obtained in Example 2 and Example 5 were obtained by scanning electron micrographs (× 150) in FIGS. 3 and 4, respectively.
As shown in (0), it was spherical.

Table 1 shows the main production conditions and Table 2 shows the properties of the composite granules. The products obtained in Comparative Examples 1 and 2 were, as a result of observation with an electron microscope, a mixture in which the inorganic particles and the resin were separated. Note that “KBE403” and “KBE903” used as lipophilic agents are both silane coupling agents manufactured by Shin-Etsu Chemical Co., Ltd.
"Plenact TTS" is a titanate coupling agent manufactured by Ajinomoto Co., Inc.

<Coating with Resin> Examples 18 to 26 Example 18 2 g of melamine, 5 g of 37% formalin, 50 g of composite granule A and 100 g of water were added to a 500 ml three-necked flask, and the solution pH was adjusted with sodium hydroxide while stirring. 8.5
To 85 ° C in 40 minutes, and
Let react for minutes. Next, the content was cooled to 30 ° C., 30 g of a 5% ammonium chloride solution was added, the temperature was raised to 85 ° C. in 60 minutes, and the mixture was reacted and cured at the same temperature for 90 minutes.

Next, the content in the flask was cooled to 30 ° C., transferred to a 11 beaker, washed several times with water, and air-dried. Then, this is reduced under reduced pressure (5 mmHg or less),
By drying at 0 ° C., coating with a melamine resin was performed. The amount of the melamine resin in the composite granular material coated with the obtained melamine resin was 1.5% by weight as a result of calculation of magnetization of the composite granular material.

The state of the melamine resin film in the composite granules coated with the melamine resin obtained in Example 18 is shown by a scanning electron micrograph (× 2000) shown in FIG.
As shown in the figure, it was confirmed that the particles were sufficiently and evenly coated with the ultrafine melamine resin.

Example 19 300 ml of xylene was placed in a 500 ml three-necked flask.
50 g of the composite particulate material A and 7.5 g of caprolactam were added with gentle stirring under a nitrogen atmosphere, the temperature was raised to 110 ° C. in 20 minutes, and the temperature was maintained for 60 minutes to dissolve caprolactam. Next, after distilling off 50 ml of xylene by azeotropic distillation under reduced pressure (20 mmHg), the pressure was returned to normal pressure, 0.56 g of sodium hydride having a purity of 64% was added, and the temperature was increased to 130 ° C. for 7 minutes. Dissolve in 50 ml, stearyl isocyanate sort 2.05
g is added for 1.5 hours and reacted at the same temperature for 30 minutes. Subsequently, the content was cooled to 30 ° C.
It was transferred to a 1-beaker, washed several times with xylene, separated into solid and liquid, and then dried at a temperature of 80 to 100 ° C. This was washed with a 1% phosphoric acid aqueous solution, further washed with water, and then subjected to solid-liquid separation.
The coating with a polyamide layer was performed by drying at a temperature of １００100 ° C.

The amount of polyamide in the composite granule covered with the obtained polyamide layer was 1.6% by weight as a result of calculation of magnetization of the composite granule. The state of the coating of the polyamide in the composite granular material coated with the polyamide layer obtained in Example 19 was sufficient and uniform as shown in the scanning electron micrograph (× 2000) in FIG. Was found to be coated. The volume electric resistance is 2.1
× 10 ¹⁰

Example 20 100 ml of water was placed in a 300 ml four-necked flask under a nitrogen stream.
1, 50 g of composite granule A, 5.3 g of acrylonitrile monomer, and 0.01 g of concentrated sulfuric acid, and 1 ° C. while stirring.
The temperature is raised to 35 ° C. at about / min, and the mixture is stirred at the same temperature for 10 minutes. Next, 0.171 g of potassium persulfate and 0.071 g of sodium sulfite are sequentially added dropwise, and the mixture is stirred at the same temperature for 2 hours. Water was added and the mixture was cooled to 20 ° C., the solid content was separated by filtration, washed with water, and air-dried. Then put it in the oven,
The coating with polyacrylonitrile was performed by heat treatment at 100 ° C.

The coating with the acrylonitrile polymer was uniform and dense from the cross section, as shown in the scanning electron micrograph (× 12000) in FIG. 7, so that the volume electric resistance was 3.8 × 10 It was as high as ¹⁰ Ω · cm. The amount of the acrylonitrile polymer on the surface of the composite granular material coated with the obtained acrylonitrile polymer was 1.7% by weight based on the composite granular material as a result of calculation from the measurement of magnetization.

Example 21 A composite particulate matter A was placed in a Henschel mixer under a nitrogen stream.
1 kg and a styrene resin (Hymer SB-75;
30 g of Sanyo Kasei Co., Ltd.)
C., and stirred at the same temperature for 1 hour. As a result of observation with a scanning electron microscope, the coating with the styrene resin was uniform and dense. Table 4 shows various properties of the composite granular material coated with the obtained styrene-based resin. The amount of coating with the styrene-based resin was 2.0% by weight based on the composite granules, as calculated from the magnetization measurement.

Examples 22 to 26 Composite particles coated with a resin were obtained in the same manner as in Example 21 except that the type of the composite particles, the type of the resin, and the mixing amount were variously changed. Table 4 shows the main manufacturing conditions and various characteristics at this time.

[0086]

[Table 1]

[0087]

[Table 2]

[0088]

[Table 3]

[0089]

[Table 4]

[0090]

The inorganic resin particle-containing epoxy resin powder according to the present invention comprises inorganic particles whose surfaces are subjected to lipophilic treatment and an epoxy resin, the particle size of which can be controlled over a wide range. Is high and the surface properties are controlled. In addition, the inorganic resin particle-containing epoxy resin granule powder according to the present invention does not contain an emulsifier, so that there is no change in the amount of charge, so that there is no problem in terms of product quality, and durability, durability, and the like. Also excellent in impact resistance and heat resistance.

[0091]

[Brief description of the drawings]

FIG. 1 is a scanning electron micrograph (× 1500) showing the particle structure of a composite granule obtained in Example 1.

FIG. 2 is a scanning electron micrograph (× 12000) showing the surface state of the composite granules obtained in Example 1.

FIG. 3 is a scanning electron micrograph (× 1500) showing the particle structure of the composite granules obtained in Example 2.

FIG. 4 is a scanning electron micrograph (× 1500) showing the particle structure of the composite granular material obtained in Example 5.

FIG. 5 is a scanning electron micrograph (× 2000) showing the particle structure of the composite granular material obtained in Example 18.

FIG. 6 is a scanning electron micrograph (× 2000) showing the particle structure of the composite granule obtained in Example 19.

FIG. 7 is a scanning electron micrograph (× 12000) showing a state of a cross section of the composite granular material obtained in Example 20.

FIG. 8 is a scanning electron micrograph (× 1000) showing the particle structure of the composite granule obtained in Example 21.

FIG. 9 is a scanning electron micrograph (× 1000) showing the particle structure of the composite granule obtained in Example 22.

Continued on the front page (51) Int.Cl. ⁷ Identification code FI G03G 9/083 H01F 1/36 9/113 1/00 C H01F 1/00 G03G 9/10 341 1/36 9/08 302 (C08K 9 / 06 3:00 5: 541) (56) References JP-A-60-188419 (JP, A) JP-A-59-170114 (JP, A) JP-A-60-163916 (JP, A) JP-A Sho 61 -1666827 (JP, A) JP-A-61-87721 (JP, A) JP-A-4-11624 (JP, A) JP-A-4-866749 (JP, A) JP-A-4-100850 (JP, A) (58) Investigated field (Int.Cl. ⁷ , DB name) C08L 63/00-63/10 C08K 9/06 C08J 7/04 C09C 3/10 H01F 1/00 H01F 1/36 G03G 9/08- 9/10

Claims (1)

(57) [Claims] Claims: 1. A surface comprising lipophilic inorganic particles and a cured epoxy resin having a number average particle diameter of 1
１０００1000 μm, and the content of the inorganic particles is 8
An inorganic resin particle-containing epoxy resin granule powder characterized in that the surface of the granule of the composite granule in an amount of 0 to 99% by weight is coated with a resin.