JP2015010120A - Cured epoxy resin fine particle, dispersion liquid thereof and method for manufacturing them - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide cured epoxy resin fine particles excellent in burnability during sintering, a dispersion liquid thereof, and methods for manufacturing them.SOLUTION: The dispersion liquid of the cured epoxy resin fine particles is manufactured by adding an amine based hardener (B) to an emulsion having an aliphatic glycidyl ether type epoxy resin (A) having at least three or more epoxy groups in one molecular and dropwisely dispersed in a dispersion medium to cure the epoxy resin (A) and the amine based hardener (B) into particles.

Description

  The present invention relates to fine particles of cured epoxy resin excellent in burn-out properties during firing, dispersions thereof, and methods for producing them.

  The resin fine particles are fine particles made of a resin, and generally have a variety of fine particles having a diameter ranging from several tens of nm to several hundreds of μm. Unlike resin molded products such as films, fibers, injection molded products, and extrusion molded products, resin fine particles are used to modify and improve various materials by using a large specific surface area and the structure of fine particles. Yes. Major applications include cosmetic modifiers, toner additives, rheology modifiers such as paints, medical diagnostic inspection agents, additives to molded articles such as automotive materials and building materials. In addition, by utilizing the fine particle structure of resin fine particles, it is also used as a raw material for rapid prototyping and rapid manufacturing, which are methods for producing custom molded products in combination with laser processing technology.

  In particular, in recent years, attention has been focused on the use of electronic information materials as members. Among them, the resin fine particles used as a porous material for metal oxides contained in dye-sensitized solar cells are required to have good dispersibility in metal oxides and excellent burn-out during firing. (Non-Patent Document 1).

  Acrylic resin fiber has been proposed as a porous agent for metal oxides contained in dye-sensitized solar cells, but it has a good dispersibility during firing, but it has a poor dispersibility in metal oxides. (For example, refer to Patent Document 1).

  On the other hand, epoxy resins have excellent characteristics such as heat resistance, adhesiveness, water resistance, abrasion resistance, chemical resistance, mechanical strength and electrical characteristics, and are widely used in the industrial field. Conventionally, fine particles made of a cured epoxy resin have been developed taking advantage of the characteristics of the epoxy resin, such as high hardness after curing, heat resistance and chemical resistance.

  As a method for producing such fine particles of cured epoxy resin, a method of curing an epoxy resin in a supercritical carbon dioxide by adding an epoxy curing agent (see, for example, Patent Document 2), an epoxy resin emulsion A method of adding an amine-based epoxy curing agent to the resin to cure it into fine particles (for example, see Patent Document 3), and a method of performing seed polymerization by impregnating an epoxy resin using a general-purpose polymer as seed particles (for example, see Patent Document 4) Etc. are known.

JP 2011-210553 A JP 2008-208164 A JP-A-6-279570 JP-A-2-228318

Journal of Materials Chemistry, Vol. 22, pages 16201-16204 (2012)

  In a method for forming a porous layer by using a metal oxide containing resin fine particles as a porous material for a metal oxide contained in a dye-sensitized solar cell, burning the resin fine particles by decomposition or oxidation during firing, and the like. It is desirable that the pores formed by the burning of the resin fine particles are pores that are present independently and uniformly in the porous metal oxide layer and that are as nearly spherical as possible. When such a porous metal oxide layer is used as an electrode for a dye-sensitized solar cell, it is expected that the movement of electric charges in the vertical direction is more efficient in a true spherical hole. Therefore, if a porous metal oxide layer having spherical vacancies can be formed, it is expected that a dye-sensitized solar cell excellent in photoelectric conversion efficiency can be provided.

  However, when a porous metal oxide layer is manufactured using an acrylic resin fiber as described in Patent Document 1, there are two pores in the resulting metal oxide layer because an acrylic resin is used. The above-mentioned resin fibers are connected and aggregated to become large, or flattened voids that are crushed are generated, so that it is impossible to obtain voids close to a spherical shape.

  In addition, the epoxy resin particles described in Patent Documents 2 to 4 are epoxy resins containing aromatic rings such as general-purpose bisphenol A type epoxy resins and bisphenol F type epoxy resins, and are included in dye-sensitized solar cells. Although the dispersibility in the oxide layer was good, the heat resistance was high, and the fired property during firing was poor, making it unsuitable as a porous material.

  Therefore, the present invention is useful as a porous material for a metal oxide contained in a dye-sensitized solar cell, and is a cured epoxy resin fine particle excellent in burnout, its dispersion, and industrially advantageous thereof. It is an object to provide a simple manufacturing method.

  As a result of intensive studies, the present inventors can solve the above problems by combining an aliphatic glycidyl ether type epoxy resin having at least three epoxy groups in one molecule and an amine curing agent. And reached the present invention.

That is, the present invention
[1] A number average particle comprising an epoxy resin cured product obtained by curing an aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule and an amine curing agent (B). Epoxy resin cured product fine particles having a diameter of 0.05 μm or more and 1000 μm or less,
[2] The amine curing agent (B) is at least one selected from the group consisting of an aliphatic amine curing agent, an alicyclic amine curing agent, an aromatic amine curing agent, and a heterocyclic amine curing agent. The cured epoxy resin fine particles according to [1], characterized in that
[3] Aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule is sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, pentaerythritol polyglycidyl ether, trimethylolpropane polyglycidyl ether Epoxy resin cured fine particles according to [1] or [2], which are at least one selected from the group consisting of: diglycerol polyglycidyl ether, and glycerol polyglycidyl ether;
[4] A cured epoxy resin particle dispersion in which the cured epoxy resin particle according to any one of [1] to [3] is dispersed in a dispersion medium,
[5] An amine curing agent (B) is added to an emulsion in which an aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule is dispersed in a dispersion medium, and the epoxy The method for producing a fine particle dispersion of cured epoxy resin according to [4], wherein the resin (A) and the amine-based curing agent (B) are cured in a particulate form,
[6] The cured epoxy resin particles according to any one of [1] to [3], wherein the cured epoxy resin particles are separated from the dispersion of the cured epoxy resin particles obtained by the production method according to [5]. Manufacturing method of fine particles,
It is.

  The fine particles of the cured epoxy resin of the present invention have better dispersibility in the metal oxide contained in the dye-sensitized solar cell than the conventional epoxy resin-based fine particles, and are burnable when the metal oxide is fired. Is excellent. In addition, since it has a low particle size distribution index and a high sphericity, the epoxy resin cured fine particle powder or aqueous dispersion of the present invention has various spacers, matting agents for paints, abrasives, and organic fillers for composite resins. It is also useful for various industrial applications such as pigment fixing agents, solid lubricants, lubricants, and release agents.

  Hereinafter, the present invention will be described in more detail.

  In the present invention, an aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule is produced by condensation of an aliphatic alcohol, an aliphatic amine or an aliphatic thiol with epichlorohydrin. And an epoxy resin having three or more glycidyl groups in one molecule. Specifically, sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, pentaerythritol polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, polyglycidyl ether of aliphatic polyhydric alcohol, etc. Is mentioned. These compounds can be used alone or in admixture of two or more. Among them, sorbitol polyglycidyl ether and pentaerythritol polyglycidyl ether are more preferable. For example, “Denacol” (registered trademark) EX-611 (manufactured by Nagase ChemteX), “Denacol” (registered trademark) EX-411 (manufactured by Nagase Chemtex) Etc. are commercially available. Since it is an aliphatic compound, it has good burn-out properties, and when it has a functional group having three or more functional groups in the molecule, it can take a crosslinked structure and form fine particles. On the other hand, although bifunctional aliphatic compounds have good burn-off properties, they cannot form particle shapes, and non-aliphatic epoxy resins represented by aromatic epoxy resins have poor burn-out properties. It is difficult to achieve the task.

  As the aliphatic glycidyl ether type epoxy resin having at least three epoxy groups in one molecule according to the present invention, other epoxy resins can be used as long as the effects of the present invention are not impaired. A blending amount of 30% by mass or less, preferably 20% by mass or less, and more preferably 10% by mass or less can be mixed with the ether type epoxy resin. Examples of epoxy resins that can be used in combination include bisphenol A type epoxy resins, bisphenol F type epoxy resins, cresol novolac type epoxy resins, phenol novolac type epoxy resins, biphenyl type epoxy resins, stilbene type epoxy resins, and hydroquinone type epoxy resins. , Naphthalene skeleton type epoxy resin, tetraphenylolethane type epoxy resin, trishydroxyphenylmethane type epoxy resin, dicyclopentadienephenol type epoxy resin, 3,4-epoxycyclohexenylmethyl-3 ′, 4′-epoxycyclohexene carboxylate , Cycloaliphatic epoxy resins such as vinylcyclohexene diepoxide, diglycidyl ether of bisphenol A ethylene oxide adduct, bisphenol A propylene Diglycidyl ether of oxide adduct, cycloglycan dimethanol diglycidyl ether, polyglycidyl ester of polybasic acid such as diglycidyl ester of hexahydrophthalic anhydride, alkyl glycidyl ether such as butyl glycidyl ether and lauryl glycidyl ether, phenyl glycidyl ether, Examples thereof include glycidyl ether having one epoxy group such as cresyl glycidyl ether. These compounds can be used alone or in admixture of two or more.

  The amine curing agent (B) in the present invention is at least one selected from the group consisting of an aliphatic amine curing agent, an alicyclic amine curing agent, an aromatic amine curing agent, and a heterocyclic amine curing agent. It is an amine-based curing agent. These can be appropriately selected according to the use and purpose.

  Specific examples of the aliphatic amine curing agent include alkylene diamines having 2 to 6 carbon atoms (ethylene diamine, propylene diamine, tetramethylene diamine, pentamethylene diamine, hexamethylene diamine, etc.), polyalkylenes (2 to 6 carbon atoms). Polyamines (diethylenetriamine, iminobispropylamine, bis (hexamethylene) triamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, etc.), alkyl or hydroxyalkyl substituents thereof (dialkylaminopropylamine, trimethylhexamethylenediamine, Aminoethylethanolamine, methyliminobispropylamine, etc.), alicyclic or heterocyclic containing aliphatic polyamines such as 3,9-bis (3-aminopropyl) -2,4 , 10-tetraoxaspiro [5,5] undecane, for example, xylylenediamine include tetrachloro -p- xylylenediamine.

  Examples of the alicyclic amine-based curing agent include 1,3-diaminocyclohexane, isophoronediamine, mensendiamine, 4,4′-methylenedicyclohexanediamine (hydrogenated methylenedianiline), and bis (4-amino-3- Methyldicyclohexyl) methane and the like.

Examples of the heterocyclic amine curing agent include piperazine, 1-aminoethylpiperazine, 1,4-diaminoethylpiperazine, 3-aminopyrrolidine, 2- (2-aminoethyl) pyrrolidine, 4,4′-bipiperazine, 4 , 4′-ethylenedipiperidine, 4,4′-trimethylenedipiperidine, 4- (aminomethyl) piperidine, 3- (4-aminobutyl) piperidine, and the like.

  The number average particle diameter of the cured epoxy resin fine particles of the present invention is 0.05 to 1000 μm. The upper limit is preferably 500 μm or less, more preferably 200 μm or less, still more preferably 100 μm or less, particularly preferably 50 μm or less, and particularly preferably 10 μm or less, most preferably 5 μm or less. The preferable lower limit is 0.07 μm or more, and more preferably 0.1 μm or more. If the particle size of the cured epoxy resin particles is smaller than this range, production is difficult, and if the particle size of the cured epoxy resin particles exceeds this range, precipitation tends to occur when the dispersion is made into a dispersion. There is.

  The number average particle diameter of the cured epoxy resin fine particles referred to here can be calculated by measuring the diameter of 100 particles randomly selected from a scanning electron micrograph and calculating the arithmetic average thereof. In the above photograph, when the particle is not a perfect circle, that is, when it is oval, the maximum particle diameter is defined as the particle diameter. In order to accurately measure the particle diameter, for example, in the case of epoxy resin cured fine particles having a number average particle diameter of 100 μm, the particle diameter is measured at a magnification of at least 50 times, preferably 100 times or more. In addition, if the epoxy resin cured fine particles have a number average particle size of 0.5 μm, it is preferable to measure at a magnification of at least 5000 times, preferably 10,000 times or more.

  Further, the particle size distribution index is determined based on the value of the particle diameter obtained above based on the following numerical conversion formulas (1) to (3).

  Ri: particle diameter of each particle, n: number of measurement 100, Dn: number average particle diameter, Dv: volume average particle diameter, PDI: particle diameter distribution index.

  In the present invention, the particle size distribution index indicating the particle size distribution of the cured epoxy resin fine particles is preferably 3 or less, and the pores formed in the metal oxide contained in the dye-sensitized solar cell are made uniform to increase the surface area. Then, the amount of dye adsorption in the metal oxide layer and the opportunity of electron transfer reaction are increased, and the effect of enhancing the power generation efficiency by light scattering can be expected, so 2 or less is preferable, more preferably 1.8 or less, More preferably, it is 1.5 or less, particularly preferably 1.4 or less, and most preferably 1.2 or less. The lower limit is theoretically 1.

  The epoxy resin cured product fine particles in the invention preferably contain 80% or more of fine particles having a sphericity of 80 or more. By containing 80% or more of fine particles having a sphericity of 80 or more, the fluidity of the cured epoxy resin particles is further improved, and the dispersibility in the metal oxide used in the dye-sensitized solar cell is good. In addition, when used as an electrode for a dye-sensitized solar cell, since a spherical hole is formed, it is expected that the movement of charges in the vertical direction within the hole will be efficient. The Therefore, the proportion of fine particles having a sphericity of 80 or more is more preferably 85% or more, still more preferably 90% or more, and most preferably 95% or more. The upper limit is 100%, that is, all fine particles are occupied with a sphericity of 80 or more.

  The average sphericity is the average of the sphericity of 30 particles randomly selected by a scanning electron microscope, and is calculated according to the following formula (4). The sphericity is the ratio of the minor axis to the major axis of each particle, and is calculated according to the following formula (5).

  Note that n is 30 measurements.

  The proportion of fine particles having a sphericity of 80 or more is, for example, an epoxy resin cured product having a number average particle diameter of 10 μm, and an area in the range of 100 μm × 100 μm is randomly selected from a fine particle scanning electron micrograph. It is calculated from the following formula (6) based on the area occupied by fine particles having a sphericity of 80 or more and the area occupied by fine particles of cured epoxy resin having a sphericity of less than 80.

Here, n _{≧ 80} : the number of fine particles having a sphericity of 80 or more, n _<80 : the number of particles of cured epoxy resin particles having a sphericity of less than ₈₀ , S _{≧ 80} : the number of fine particles having a sphericity of 80 or more Occupied area, S _<80 : An area occupied by fine particles of cured epoxy resin having a sphericity of less than 80.

  The epoxy resin cured product fine particles of the present invention have good burn-out properties. Specifically, when the heat treatment is performed at 450 ° C. for 2 hours in air, the epoxy resin cured fine particles in 100% by mass of the epoxy resin cured fine particles It is characterized in that 95% by mass or more is burned out. As a result, if the epoxy resin cured product fine particles remain in the pores or on the surface of the porous metal oxide layer that is a photoelectrode material as a residue when heat-treated, the dye adsorption area decreases, It becomes possible to become an electron trap site or to prevent the electron exchange with the electrolyte solution or gel and the solid electrolyte.

As a method for confirming the burn-out property of the cured epoxy resin fine particles, for example, it can be measured by a thermogravimetric balance test (TGA method) using a differential thermothermal gravimetric simultaneous measuring device (manufactured by Seiko Instruments Inc .: TG / DTA6200). . As a measuring method, the mass (W ₁ ) of the cured epoxy resin fine particles is calculated from the mass (W ₂ ) after baking for 2 hours at 450 ° C. (temperature increase rate: 50 ° C./min) in an air atmosphere: Calculate according to 7).

  The dispersion of fine particles of cured epoxy resin refers to a dispersion in which the cured fine particles of epoxy resin are dispersed in a dispersion medium. The solvent as the dispersion medium is selected from the group consisting of aliphatic hydrocarbon solvents, aromatic hydrocarbon solvents, ester solvents, halogen solvents, ketone solvents, alcohol solvents, polar solvents, ether solvents and water. Good at least one kind. Preferable solvents include aromatic hydrocarbon solvents, aliphatic hydrocarbon solvents, halogenated hydrocarbon solvents, alcohol solvents, ether solvents, polar solvents, and water. The most preferred dispersion medium is water.

  Examples of the aliphatic hydrocarbon solvent include pentane, hexane, heptane, octane, nonane, n-decane, n-dodecane, n-tridecane, cyclohexane, cyclopentane and the like.

  Examples of the aromatic hydrocarbon solvent include benzene, toluene, xylene and the like. Examples of ester solvents include ethyl acetate, methyl acetate, butyl acetate, ethyl propionate, and methyl propionate. Examples of the halogenated hydrocarbon solvent include chloroform, bromoform, methylene chloride, 1,2-dichloroethane, 1,1,1-trichloroethane, chlorobenzene, 2,6-dichlorotoluene and the like. Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, and methyl butyl ketone. Examples of the alcohol solvent include methanol, ethanol, 1-propanol, 2-propanol and the like. Examples of ether solvents include diethyl ether, tetrahydrofuran, diisopropyl ether, dioxane, diglyme, dimethoxyethane and the like. Examples of the polar solvent include dimethyl sulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, trimethyl phosphoric acid, N-methylpyrrolidone and the like. These solvents may be used as a mixture of two or more.

  From the viewpoint of operability, the epoxy resin cured product fine particles in the dispersion are preferably 60% by mass or less, and more preferably 50% by mass or less. Yes, and more preferably 40% by mass or less. Moreover, the minimum is 1 mass% or more, Preferably, it is 5 mass% or more, More preferably, it is 10 mass% or more.

  The dispersion of fine particles of the cured epoxy resin of the present invention may contain a surfactant component for the purpose of improving dispersibility. Examples of the surfactant include a cationic surfactant, an anionic surfactant, an amphoteric surfactant, and a nonionic surfactant. Examples of the anionic surfactant include fatty acid sodium, fatty acid potassium, and alkylbenzene. Sodium sulfonate, sodium alkyl sulfate, sodium alkyl sulfonate, sodium alkyl ether sulfate, monoalkyl phosphate, dialkyl phosphate, polyoxyethylene alkyl ether sodium phosphate, fatty acid ester sodium sulfonate, fatty acid ester sulfuric acid Examples include sodium ester, fatty acid alkylose amide sulfate sodium ester, sodium fatty acid amide sulfonate, and the like.

  Examples of the cationic surfactant include alkyl methyl ammonium chloride, alkyl trimethyl ammonium chloride, dialkyl dimethyl ammonium chloride, alkyl dimethyl benzyl ammonium chloride, and alkyl pyridinium chloride.

  Examples of zwitterionic surfactants include alkylaminocarboxylates, carboxybetaines, alkylbetaines, sulfobetaines, phosphobetaines, and the like.

  Nonionic surfactants include sucrose fatty acid ester, polyoxyethylene fatty acid ester, polyoxyethylene lanolin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene glycol monofatty acid ester, fatty acid alkanolamide, fatty acid monoethanolamide. , Fatty acid diethanolamide, fatty acid triethanolamide, polyoxyethylene fatty acid amide, isopropanolamide, alkylamine oxide, polyoxyethylene amine, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene styrenated phenyl ether and these And derivatives thereof.

  The alkyl referred to here is, for example, a linear saturated hydrocarbon group having 1 to 30 carbon atoms, a branched saturated hydrocarbon group, a linear unsaturated hydrocarbon group, or a branched unsaturated hydrocarbon. Groups. In particular, the surfactant used in the present invention is preferably a polyoxyethylene alkyl ether, a polyoxyethylene styrenated phenyl ether or a derivative thereof contained in the above. The preferred range of the alkyl group is a linear saturated hydrocarbon group having 1 to 20 carbon atoms, a branched saturated hydrocarbon group, a linear unsaturated hydrocarbon group, or a branched unsaturated hydrocarbon group. good. Particularly preferred surfactants include those having the following structure.

  In the formula, m is an integer of 1 to 3, and n is an integer of 5 to 100, preferably 10 to 40.

  Since polyoxyethylene alkyl ether, polyoxyethylene styrenated phenyl ether and derivatives thereof have an appropriate HLB (Hydrophile-Lipophile Balance) value with respect to fine particles of the cured epoxy resin, While improving the dispersibility to a dispersion medium, the obtained dispersion liquid can maintain the dispersibility stable in the long term.

Next, a method for obtaining fine particles of cured epoxy resin of the present invention and a dispersion thereof will be described.
The fine particles of cured epoxy resin of the present invention are prepared by adding an amine-based curing agent (B) to an emulsion in which an aliphatic glycidyl ether type epoxy resin (A) component having at least three epoxy groups in one molecule is dispersed in the form of droplets. In addition, it can be obtained by curing the component (A) in the form of particles. As a method for producing an epoxy resin emulsion, typical methods are listed below, but these methods are not particularly limited in the present invention.
(1) A method in which an epoxy resin or a solution thereof is continuously discharged from a nozzle that vibrates in the air or in a liquid, and is cut into droplets and collected in the liquid.
(2) A method of discharging an epoxy resin or a solution thereof in a pulse form from a nozzle in the air or in a liquid and collecting it in the liquid.
(3) A method of emulsifying an epoxy resin or a solution thereof using a surfactant.
(4) A method of emulsifying an epoxy resin or a solution thereof using a powder emulsifier.
(5) A method of emulsifying an epoxy resin or a solution thereof with water containing a protective colloidal substance.

  Among the above methods, the methods (3) to (5) are preferably used in the present invention from the viewpoint of productivity, but the methods (1) to (5) may be combined.

  As the dispersion medium in the above method, the above-described dispersion medium can be used. Among these, the above-mentioned alcohol-based solvent or water-based medium such as water may be used for ease of embodiment of the present invention, ease of handling, separability from the organic solvent used, and economic reasons. Water is particularly preferable.

  Further, the surfactant in the above method is not particularly limited, but the above-mentioned cationic surfactant, anionic surfactant, zwitterionic surfactant, and nonionic surfactant can be used. . Of these, nonionic surfactants are preferred from the viewpoint of emulsion stability. Surfactants can be used alone or in combination of two or more. These surfactants can be added in an amount of about 0.5 to 30% by mass with respect to a solution or dispersion of a mixture of an epoxy resin and a curing agent. The number average particle size of the epoxy cured product fine particles can be adjusted according to the amount of the surfactant added, and when it is less than 0.5% by mass, coalescence of the emulsions occurs during curing and the particles are obtained as particles. Since it disappears, it is not preferable.

  Moreover, as a powder emulsifier, there exist fine powder crystalline cellulose, barium sulfate powder, etc., and about 0.5-20 mass% is used with respect to the solution of the mixture of an epoxy resin and a hardening | curing agent.

  In addition, protective colloidal substances include polyvinyl alcohol, gum arabic, carboxymethylcellulose, gelatin, sodium alginate, etc., and with respect to a solution of a mixture of an epoxy resin and a hardener in an aqueous dispersion medium such as the aforementioned alcohol solvent or water. In general, it is used by dissolving about 0.1 to 20% by mass.

  Next, a representative example of a method for emulsifying an epoxy resin or a solution thereof to obtain an emulsion will be described.

  A surfactant or a powder emulsifier is added to the epoxy resin, and when a protective colloidal substance is added, it is generally dissolved in a dispersion medium, but the epoxy resin and the surfactant, the powder emulsifier or Depending on the compatibility of the protective colloidal substance, the surfactant or powder emulsifier may be dissolved in a dispersion medium and added, or the protective colloidal substance may be added to the epoxy resin.

  As a method of emulsifying and dispersing an epoxy resin in a dispersion medium, the above-mentioned epoxy resin or a solution thereof is gradually added to a strongly stirred dispersion medium, or conversely, a dispersion medium is added to a strongly stirred epoxy resin or a solution thereof. A phase-inversion emulsification type that gradually converts to a water-in-oil (hereinafter sometimes referred to as “W / O”) type emulsion to an oil-in-water (hereinafter also referred to as “O / W”) type emulsion. The emulsion forming method is generally used. When the viscosity of the epoxy resin or the solution thereof is low, emulsification is possible by either method, but when the viscosity is high, the latter method, that is, the epoxy resin or its solution that is vigorously stirred is dispersed in the latter method. A phase inversion emulsification method is recommended, in which is gradually added.

  Since the epoxy resin generally has a viscosity of 1 poise or more, the latter method is preferably used.

  The mixing apparatus in this step may be any mixture that can provide the above emulsion. Considering efficient dispersion of a dispersed phase mainly composed of a high-viscosity epoxy resin in an aqueous phase, for example, a homomixer, a disperser, etc. It is preferable to use an apparatus having a strong shearing force such as

  The mixing temperature in the above step is not particularly limited and can be appropriately selected. However, it is preferably 10 to 90 ° C, more preferably 25 to 60 ° C. When the mixing temperature is less than 10 ° C., the viscosity of the dispersed phase is too high and the particles may not be uniformly dispersed, and many coarse particles exceeding 1000 μm may be generated. The droplets coalesce, and particles with a small particle size cannot be obtained.

  The compounding amount of the curing agent is 1/5 to 5/1, preferably 1/3 to the molar ratio of the active hydrogen of the curing agent to the molar number of the epoxy functional group in the epoxy resin. 3/1, more preferably 1/2 to 2/1. The curing agent may be added as it is, or may be previously dissolved or dispersed in the epoxy resin before emulsification, but it is preferable to add it in a solution state for uniform curing. Any solvent can be used as long as it can dissolve the curing agent, and a preferable one is the same as the dispersion medium of the epoxy resin, and a particularly preferable one is water.

  The heating temperature for curing the epoxy resin is preferably 20 ° C to 200 ° C, more preferably 20 ° C to 100 ° C, and even more preferably 40 ° C to 80 ° C. The time for performing the curing reaction is preferably in the range of 10 minutes to 100 hours, more preferably 30 minutes to 10 hours, and even more preferably 1 hour to 5 hours. In addition, the reaction atmosphere may be any of air, an inert gas atmosphere such as nitrogen, argon, carbon dioxide, or the like, but is preferably a nitrogen atmosphere.

  The stirring speed when the epoxy resin is cured to form fine particles is preferably 100 to 1600 rpm, more preferably 200 to 900 rpm, and still more preferably 300 to 600 rpm.

  By operating at these temperature, time, and stirring conditions, a dispersion of the desired cured epoxy resin particles can be obtained without agglomeration and fusion.

  The cured epoxy resin particles can be obtained by solid-liquid separation of the cured epoxy resin particles from the dispersion obtained by the above-described method for producing a dispersion of cured epoxy resin particles.

  The method for separating fine particles of cured epoxy resin is not particularly limited, and a known method such as a centrifugal separation method, a filtration separation method, spray drying, or centrifugal precipitation can be used.

  In the present invention, other additives may be included. The most typical additives are antioxidants, colorants and viscosity modifiers. These are usually added before the mixture is suspended or emulsified.

  Thus, the cured epoxy resin fine particles produced by the method of the present invention can be usefully used as a material for forming a porous material such as a metal oxide electrode contained in a dye-sensitized solar cell, In addition, since the epoxy resin cured fine particles inherently have high hardness and chemical resistance characteristics and high sphericity, they are particularly suitable as various spacers.

  In addition, it can be expected to be applied to cosmetic modifiers, toner additives, rheology modifiers such as paints, medical diagnostic inspection agents, mechanical properties improvers for molded products such as automotive materials and building materials, Further, by adding the fine particles of the cured epoxy resin to a thermoplastic resin, it can be expected to improve its mechanical properties, so that it can be expected as a material for improving mechanical properties of resin molded products, films, fibers and the like.

  Specific examples of the resin molded body, film, fiber, etc. include, for example, electrical equipment housings, OA equipment housings, various covers, various gears, various cases, sensors, LED lamps, connectors, sockets, resistors, Relay case, switch, coil bobbin, condenser, variable capacitor case, optical pickup, oscillator, various terminal boards, transformer, plug, printed wiring board, tuner, speaker, microphone, headphones, small motor, magnetic head base, power module, housing , Semiconductors, LCDs, motor brush holders, parabolic antennas, computer-related parts and other electrical and electronic parts; VTR parts, TV parts, irons, hair dryers, rice cooker parts, microwave oven parts, acoustic parts, audio Audio equipment parts such as laser discs (registered trademark) and compact discs, lighting parts, refrigerator parts, air conditioner parts, typewriter parts, word processor parts, home appliances such as office electrical appliance parts, office computer parts, telephone parts , Facsimile related parts, copier related parts, cleaning jigs, oilless bearings, stern bearings, underwater bearings and other bearings, motor related parts such as motor parts, lighters, typewriters, microscopes, binoculars, Optical equipment such as cameras and watches, precision machinery-related parts: alternator terminals, alternator connectors, IC regulators, various valves such as exhaust gas valves, various fuel / exhaust / intake system pipes, air intake nozzle snorkels, intake manifolds , Fuel pump, engine coolant joint, carburetor main body, carburetor spacer, exhaust gas sensor, coolant sensor, oil temperature sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter, thermostat for air conditioner Base, heating hot air flow control valve, brush holder for radiator motor, water pump impeller, turbine vane, wiper motor related parts, dust distributor, starter switch, starter relay, transmission wire harness, window washer nozzle, air conditioner panel switch board , Coils for fuel-related solenoid valves, connectors for fuses, horn terminals, electrical components Product insulating plates, step motor rotors, lamp sockets, lamp reflectors, lamp housings, brake pistons, solenoid bobbins, engine oil filters, ignition device cases, and the like. In addition, because of its excellent transparency and heat resistance, it is used as a component for optical recording / communications, such as imaging equipment, such as cameras, VTRs, projection TVs, viewfinders, filters, prisms, and Fresnel lenses. Various optical equipment (VD, CD, DVD, MD, LD, etc.) substrates, various disc substrate protective films, optical disc player pickup lenses, optical fibers, optical switches, optical connectors, and other information equipment related parts such as liquid crystal displays, flat panel displays, plasmas Display light guide plate, Fresnel lens, polarizing plate, polarizing plate protective film, retardation film, light diffusion film, viewing angle widening film, reflective film, antireflection film, antiglare film, brightness enhancement film, prism sheet, pickup lens , Light guide films for touch panels, covers, etc., as parts related to transportation equipment such as automobiles, tail lamp lenses, head lamp lenses, inner lenses, amber caps, reflectors, extensions, side mirrors, room mirrors, side visors, instrument needles, instrument covers , Glazing typified by window glass, etc. as medical equipment related parts, spectacle lenses, spectacle frames, contact lenses, endoscopes, optical cells for analysis, etc., as building material related parts, lighting windows, road translucent plates, lighting covers It can also be applied to signboards, translucent sound insulation walls, bathtub materials, etc., and is useful for these various applications.

  EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited to these.

(1) Measuring method of average particle size and particle size distribution index The number average particle size of the cured epoxy resin particles is adjusted to 18000 G for 10 minutes after adjusting the slurry of the particles with 20% by mass of ion-exchanged water. After implementation, decantation was performed to obtain a solid content. A sample for measurement was obtained by vacuum drying the solid content at 60 ° C. for 4 hours. Images were taken using a scanning electron microscope (JSM-6301NF: manufactured by JEOL Ltd.). Regarding the photographing magnification, the cured epoxy resin fine particles having a number average particle diameter of 100 μm are measured at a magnification of 50 times or more, and the cured epoxy resin fine particles having a number average particle diameter of 0.5 μm are multiplied by 10,000 times or more. Measured with

  100 particle diameters randomly selected from the taken scanning electron micrographs were measured and calculated according to the formulas (1) to (3). In the above photograph, when the particle is not a perfect circle, that is, when it is oval, the maximum particle diameter is defined as the particle diameter.

  Ri: particle diameter of each particle, n: number of measurement 100, Dn: number average particle diameter, Dv: volume average particle diameter, PDI: particle diameter distribution index.

(2) Measuring method of average sphericity The average sphericity of the cured epoxy resin fine particles is the trueness of 30 particles randomly selected with a scanning electron microscope (JSM-6301NF: manufactured by JEOL Ltd.). It is an average of sphericity, and was calculated according to the formula (4). The sphericity is the ratio of the minor axis to the major axis of each particle, and was calculated according to formula (5).

  Note that n is 30 measurements.

(3) Method for calculating the content of fine particles having a sphericity of 80 or more The proportion of fine particles having a sphericity of 80 or more contained in the cured epoxy resin particles does not have an area in the range of 100 μm × 100 μm from a scanning electron micrograph. It selected according to work, and it computed according to Formula (6) from the area which the fine particle of 80 or more sphericity occupies, and the area which the epoxy resin hardened | cured material fine particle of a form smaller than sphericity 80 occupies.

Here, n _{≧ 80} : the number of fine particles having a sphericity of 80 or more, n _<80 : the number of particles of cured epoxy resin particles having a sphericity of less than ₈₀ , S _{≧ 80} : the number of fine particles having a sphericity of 80 or more Occupied area, S _<80 : An area occupied by fine particles of cured epoxy resin having a sphericity of less than 80.

(4) Evaluation method of burnout property of fine particles The evaluation method of burnout property of fine particles of cured epoxy resin was performed by using 10 mg of dry cured epoxy resin particles and a differential thermothermal gravimetric simultaneous measurement apparatus (manufactured by Seiko Instruments Inc .: TG / It was measured by a thermogravimetric balance test (TGA method) using DTA6200). As a measurement method, the mass of the epoxy resin cured product fine particles (W ₁ ) is calculated from the mass (W ₂ ) after firing for 2 hours at 450 ° C. (temperature increase rate: 50 ° C./min) in an air atmosphere. Calculated according to (7).

Example 1 <Method for Producing Sorbitol Polyglycidyl Ether / Piperazine Fine Particles>
In a 500 mL separable flask, 20 parts by mass of sorbitol polyglycidyl ether (“Denacol EX” (registered trademark) EX-622 manufactured by Nagase ChemteX Corporation) and polyoxyethylene styrenated phenyl ether (Daiichi Kogyo Seiyaku Co., Ltd., 9.66 parts by mass of “Neugen” (registered trademark) EA-177) was added, heated to 40 ° C., and stirred for 10 minutes at 350 rpm using one inclined paddle blade. While stirring at 350 rpm, 40 parts by mass of ion exchange water as a dispersion medium is dropped at a speed of 1.0 part by mass / minute via a liquid feed pump, and after forming a W / O type emulsion, An O / W type emulsion was prepared. Then, piperazine hexahydrate (manufactured by Tokyo Chemical Industry Co., Ltd., special grade) as a curing agent (B) 6.09 parts by mass (ratio of the number of moles of active hydrogen of the curing agent to the number of moles of epoxy functional group: 3.7) ) In 20 parts by mass of ion-exchanged water is added dropwise at a rate of 1.0 part by mass / min via a feed pump, and then at 40 ° C. and a stirring speed of 350 rpm for 15 hours. A dispersion of fine particles of cured epoxy resin was obtained by performing a curing reaction. The dispersion was filtered and dried in vacuo. The number average particle size of the obtained fine particles is 0.21 μm, the particle size distribution index is 1.12, the average sphericity is 98.7, the fineness of the sphericity is 80 or more is 96%, and the burnout evaluation is 96.3 mass. % Burnout was confirmed.

Example 2 <Pentaerythritol polyglycidyl ether / piperazine microparticle production method>
In a 500 mL separable flask, 20 parts by mass of pentaerythritol polyglycidyl ether (“Denacol EX” (registered trademark) EX-411 manufactured by Nagase ChemteX Corporation) and polyoxyethylene styrenated phenyl ether (Daiichi Kogyo Seiyaku Co., Ltd.) , "Neugen" (registered trademark) EA-177) 9.66 parts by mass was added, heated to 40 ° C, and stirred at 350 rpm for 10 minutes using one inclined paddle blade. While stirring at 350 rpm, 40 parts by mass of ion exchange water as a dispersion medium is dropped at a speed of 1.0 part by mass / minute via a liquid feed pump, and after forming a W / O type emulsion, An O / W type emulsion was prepared. Then, piperazine hexahydrate (manufactured by Tokyo Chemical Industry Co., Ltd., special grade) as a curing agent (B) 5.08 parts by mass (ratio of moles of active hydrogen in the curing agent to moles of epoxy functional group: 4.3) ) In 20 parts by mass of ion-exchanged water is added dropwise at a rate of 1.0 part by mass / min via a feed pump, and then at 40 ° C. and a stirring speed of 350 rpm for 15 hours. A dispersion of fine particles of cured epoxy resin was obtained by performing a curing reaction. The dispersion was filtered and dried in vacuo. The obtained fine particles had a number average particle size of 2.3 μm, a particle size distribution index of 1.22, an average sphericity of 97.1, 96% of fine particles having a sphericity of 80 or more, and 95.7 mass in the burnout evaluation. % Burnout was confirmed.

Example 3 <Method for producing sorbitol polyglycidyl ether / piperazine fine particles>
In a 500 mL separable flask, 20 parts by mass of sorbitol polyglycidyl ether (“Denacol EX” (registered trademark) EX-622 manufactured by Nagase ChemteX Corporation) and polyoxyethylene styrenated phenyl ether (Daiichi Kogyo Seiyaku Co., Ltd., “Neugen” (registered trademark) EA-177) 3.22 parts by mass was added, heated to 40 ° C., and stirred at 350 rpm for 10 minutes using one inclined paddle blade. While stirring at 350 rpm, 40 parts by mass of ion exchange water as a dispersion medium is dropped at a speed of 1.0 part by mass / minute via a liquid feed pump, and after forming a W / O type emulsion, An O / W type emulsion was prepared. Then, piperazine hexahydrate (manufactured by Tokyo Chemical Industry Co., Ltd., special grade) as a curing agent (B) 6.09 parts by mass (ratio of the number of moles of active hydrogen of the curing agent to the number of moles of epoxy functional group: 3.7) ) In 20 parts by mass of ion-exchanged water is added dropwise at a rate of 1.0 part by mass / min via a feed pump, and then at 40 ° C. and a stirring speed of 350 rpm for 15 hours. A dispersion of fine particles of cured epoxy resin was obtained by performing a curing reaction. The dispersion was filtered and dried in vacuo. The number average particle size of the obtained fine particles is 131 μm, the particle size distribution index is 1.29, the average sphericity is 96.6, the fineness of the sphericity is 80 or more is 96%, and the burnout evaluation is 96.0% by mass. Burnout was confirmed.

Example 4 <Method for Producing Sorbitol Polyglycidyl Ether / Triethylenetetramine Fine Particles>
In a 500 mL separable flask, 20 parts by mass of sorbitol polyglycidyl ether (“Denacol EX” (registered trademark) EX-622 manufactured by Nagase ChemteX Corporation) and polyoxyethylene styrenated phenyl ether (Daiichi Kogyo Seiyaku Co., Ltd., 9.66 parts by mass of “Neugen” (registered trademark) EA-177) was added, heated to 40 ° C., and stirred for 10 minutes at 350 rpm using one inclined paddle blade. While stirring at 350 rpm, 40 parts by mass of ion exchange water as a dispersion medium is dropped at a speed of 1.0 part by mass / minute via a liquid feed pump, and after forming a W / O type emulsion, An O / W type emulsion was prepared. Thereafter, 2.92 parts by mass of triethylenetetramine (manufactured by Wako Pure Chemical Industries, Ltd., primary) as the curing agent (B) (ratio of the number of moles of active hydrogen of the curing agent to the number of moles of the epoxy functional group: 1.9) A curing agent aqueous solution dissolved in 20 parts by mass of ion-exchanged water is dropped at a speed of 1.0 part by mass / min via a feed pump, and then a curing reaction is performed at 40 ° C. and a stirring speed of 350 rpm for 15 hours. To obtain a dispersion of fine particles of cured epoxy resin. The dispersion was filtered and dried in vacuo. The number average particle size of the obtained fine particles was 0.36 μm, the particle size distribution index was 1.23, the average sphericity was 97.0, the fine particles having a sphericity of 80 or more were 95%, and the burnout evaluation was 97.8 mass. % Burnout was confirmed.

Comparative Example 1 <Method for Producing Bisphenol A Diglycidyl Ether / Piperazine Fine Particles>
In a 300 mL separable flask, 100 parts by mass (0.026 mol) of bisphenol A diglycidyl ether (“jER” (registered trademark) 828, manufactured by Mitsubishi Chemical Corporation) as an aromatic epoxy resin and polyoxyethylene styrenated phenyl ether ( 16.12 parts by mass of “Neugen” (registered trademark) EA-177, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was added, heated to 40 ° C., and stirred at 350 rpm for 20 minutes using one four inclined paddle blades. While stirring at 350 rpm, 65 parts by mass of ion exchange water as a dispersion medium is dropped at a speed of 1.3 parts by mass / minute via a liquid feed pump, and after forming a W / O type emulsion, An O / W type emulsion was prepared. Thereafter, piperazine hexahydrate (manufactured by Tokyo Chemical Industry Co., Ltd., special grade) 32 parts by mass (ratio of the number of moles of active hydrogen of the curing agent to the number of moles of the epoxy functional group: 1.8) as the curing agent (B). A curing agent aqueous solution dissolved in 150 parts by mass of ion-exchanged water is dropped at a speed of 4.0 parts by mass / min via a liquid feed pump, and then a curing reaction is performed at 40 ° C. and a stirring speed of 350 rpm for 24 hours. To obtain a dispersion of fine particles of cured epoxy resin. The dispersion was filtered and dried in vacuo. The number average particle diameter of the obtained fine particles was 0.25 μm, the average sphericity was 97.2, the fine particles having a sphericity of 80 or more were 98%, and the burnout evaluation confirmed 94.5% by mass.

Comparative Example 2 <Method for Producing Ethylene Glycol Diglycidyl Ether / Triethylene Tetramine Fine Particles>
In a 300 mL separable flask, 20 parts by mass (0.088 mol) of ethylene glycol diglycidyl ether (“Denacol EX” (registered trademark) EX-811 manufactured by Nagase ChemteX Corporation) and polyoxyethylene styrenated phenyl ether (1st 9.66 parts by mass of “Neugen” (registered trademark) EA-177, manufactured by Kogyo Seiyaku Co., Ltd.) was added, heated to 40 ° C., and stirred at 350 rpm for 10 minutes using one four inclined paddle blades. While stirring at 350 rpm, 40 parts by mass of ion exchange water as a dispersion medium is dropped at a speed of 1.0 part by mass / minute via a liquid feed pump, and after forming a W / O type emulsion, An O / W type emulsion was prepared. Subsequently, 4.32 parts by mass of triethylenetetramine (manufactured by Wako Pure Chemical Industries, Ltd., primary) as the curing agent (B) (ratio of the number of moles of active hydrogen in the curing agent to the number of moles of the epoxy functional group: 1, 3) A curing agent aqueous solution dissolved in 20 parts by mass of ion-exchanged water is dropped at a speed of 1.0 part by mass / min via a liquid feed pump, and then a curing reaction is performed at a stirring speed of 40 ° C. and 350 rpm. As a result, the whole was agglomerated and could not be obtained as fine particles.

Claims (6)

It consists of an epoxy resin cured product obtained by curing an aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule and an amine curing agent (B), and the number average particle diameter is Epoxy resin cured product fine particles characterized by being 0.05 μm or more and 1000 μm or less. The amine curing agent (B) is at least one selected from the group consisting of an aliphatic amine curing agent, an alicyclic amine curing agent, an aromatic amine curing agent, and a heterocyclic amine curing agent. The fine particles of cured epoxy resin according to claim 1. Aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule is sorbitol polyglycidyl ether, sorbitan polyglycidyl ether, pentaerythritol polyglycidyl ether, trimethylolpropane polyglycidyl ether, diglycerol 3. The cured epoxy resin fine particle according to claim 1, which is at least one selected from the group consisting of polyglycidyl ether and glycerol polyglycidyl ether. A cured epoxy resin particle dispersion in which the cured epoxy resin particle according to any one of claims 1 to 3 is dispersed in a dispersion medium. An amine-based curing agent (B) is added to an emulsion in which an aliphatic glycidyl ether type epoxy resin (A) having at least three epoxy groups in one molecule is dispersed in a dispersion medium, and the epoxy resin (A And the amine-based curing agent (B) are cured in the form of particles. The method for producing fine particles of cured epoxy resin according to any one of claims 1 to 3, wherein the fine particles of cured epoxy resin are separated from the dispersion of fine particles of cured epoxy resin obtained by the production method according to claim 5.