Epoxy resin composition

Abstract

Epoxy resin composition containing: coated particles comprising: (A) Hardener particles for epoxy resin and (B) Alkoxy oligomer, wherein the surfaces of the curing agent particles for epoxy resin are coated with the alkoxy oligomer; and an epoxy resin.

Description

[Technical field]

[0001] This invention is an epoxy resin composition and a sheet or layer material or composite material containing the same. [Description of the prior art]

[0002] When using an epoxy resin composition containing a solid epoxy resin curing agent as an adhesive, etc., sufficient latency of the solid epoxy resin curing agent is required to maintain the epoxy resin composition in a single-component state. Latency refers to the property that the agent exhibits no curing effect at normal temperature but functions as a curing agent when heated. If the latency of the solid epoxy resin curing agent is insufficient, the epoxy resin will cure even at normal temperature, and the viscosity of the epoxy resin composition will increase. If the epoxy resin composition contains acid anhydride or organic solvent, there is a problem that the acid anhydride or organic solvent will dissolve the solid epoxy resin curing agent, thereby reducing the latency of the solid epoxy resin curing agent.

[0003] As a method for imparting latency to the curing agent, a method in which the curing agent is treated with silane coupling agents such as γ-glycidoxypropyltrimethoxysilane, etc., has been developed (see, for example, Patent Document 1), but this still needs to be further improved in terms of acid anhydride resistance and solvent resistance.

[0004] It has also been reported that when curing agent containing fine particles is treated by a dry method in which no solvent is used, there is a problem that the solid epoxy resin curing agent coagulates.

[0005] JP 2010-254775 A discloses particles coated with an alkoxy oligomer. [Documents relating to the prior art][Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-222037 [Summary of the invention][Description of the technical problem underlying the invention]

[0007] The object of this invention is to provide an epoxy resin composition containing coated particles in which agglomeration is low and which have excellent acid anhydride resistance and solvent resistance, and an epoxy resin. [Description of the problem solution through the invention]

[0008] In order to solve the above-mentioned problem, the inventors have conducted intensive studies and found that coated particles in which agglomeration is low and which have excellent acid anhydride resistance and solvent resistance can be obtained by coating the surface of the epoxy resin curing agent particles with alkoxy oligomer, thus completing this invention.

[0009] The invention relates to an epoxy resin composition containing coated particles comprising (A) curing agent particles for epoxy resin and (B) alkoxy oligomer, wherein the surfaces of the curing agent particles for epoxy resin are coated with the alkoxy oligomer; and an epoxy resin.

[0010] Furthermore, the invention relates to a sheet or layer material or composite material containing the resin composition according to the invention.

[0011] Preferred embodiments of the invention are described in the dependent claims. [Advantageous effects of the invention]

[0012] The coated particles of the epoxy resin composition according to the invention have a low tendency to agglomerate and have excellent acid anhydride resistance and solvent resistance. [Description of embodiments]

[0013] These are coated particles containing (A) epoxy resin hardener particles and (B) alkoxy oligomer with which the surface(s) of the epoxy resin hardener particles are coated. (A) Hardener particles for epoxy resin

[0014] The (A) epoxy resin curing agent particles are preferably a latent curing agent. Latency here refers to the property that the agent exhibits no curing effect at normal temperature (25°C), but functions as a curing agent when heated, for example, to 100°C. The (A) epoxy resin curing agent particles can be at least one compound selected from the group consisting of, for example, amine-based latent curing agents, urea compounds, dicyandiamide, and hydrazide compounds. From the point of view of curability, it is preferred that the curing agent particles (A) be at least one amine-based latent curing agent selected from the group consisting of a tertiary amine adduct-based latent curing agent and an imidazole adduct-based latent curing agent. Latent curing agent based on tertiary amine adduct

[0015] The tertiary amine adduct-based latent curing agent is a compound obtained by a reaction between a compound having a tertiary amino group(s) and an epoxy compound. Furthermore, the surface of the compound having a tertiary amino group(s) may be treated with an isocyanate compound, an acidic compound, or the like.

[0016] Compounds which have (a) tertiary amino group(s) which can be mentioned are, for example, dimethylaminopropylamine, diethylaminopropylamine, di-n-propylaminopropylamine, dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, N-methylpiperazine, N-aminoethylpiperazine, 1,4-bis(3-aminopropyl)piperazine, 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanolethanol, 1-phenoxymethyl-2-dimethylaminoethanol, 2-diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, dimethylaminomethylphenol, 2,4,6-tris(dimethylaminomethyl)phenol, N-β-hydroxyethylmorpholine, 2-dimethylaminoethanethiol, 1,4-diazabicyclo[2.2.2]octane, N,N-dimethyl-N'-phenylurea, N,N-dimethyl-N'-(3,4-dichlorophenyl)urea, toluenebis(dimethylurea), 4,4'-methylenebis(phenyldimethylurea), 2-mercaptopyridine, N,N-dimethylaminobenzoic acid, N,N-dimethylglycine, nicotinic acid, isonicotinic acid, picolinic acid, N,N-dimethylglycine hydrazide, N,N-dimethylpropionic acid hydrazide, nicotinic acid hydrazide, isonicotinic acid hydrazide, etc. are preferred.

[0017] As preferred examples of the epoxy compounds used as one of the raw materials of the tertiary amine adduct-based latent curing agent, there may be mentioned, among others, polyglycidyl ether obtained by a reaction between polyhydric phenol(s) such as bisphenol A, bisphenol F, catechol, resorcinol, etc., or polyhydric alcohol such as glycerin, polyethylene glycol, etc., and epichlorohydrin; glycidyl ether ester obtained by a reaction between hydroxycarboxylic acid such as p-hydroxybenzoic acid, β-hydroxynaphthoic acid, etc., and epichlorohydrin; polyglycidyl ester obtained by a reaction between polycarboxylic acid such as phthalic acid, terephthalic acid, etc., and epichlorohydrin; Glycidylamine compounds obtained by a reaction between 4,4'-diaminodiphenylmethane, m-aminophenol or the like and epichlorohydrin; in addition, multifunctional epoxy compounds, such asan epoxidized phenol novolak resin, an epoxidized cresol novolak resin, an epoxidized polyolefin, etc., as well as monofunctional epoxy compounds such as butyl glycidyl ether, phenyl glycidyl ether, glycidyl methacrylate, etc.

[0018] In the production of a latent curing agent based on tertiary amine adducts, additional components that can be added include an active hydrogen compound containing active oxygen in its molecule, diisocyanate, monoamine compound, diamine compound, urea, etc. Examples of the above-mentioned compounds containing active hydrogen include polyhydric phenols such as bisphenol A, bisphenol F, bisphenol S, hydroquinone, catechol, resorcinol, pyrogallol, phenol novolak resin, etc., polyhydric alcohols such as trimethylolpropane, etc., polybasic carboxylic acids such as adipic acid, phthalic acid, etc., as well as 1,2-dimercaptoethane, 2-mercaptoethanol, 1-mercapto-3-phenoxy-2-propanol, mercaptoacetic acid, anthranilic acid, lactic acid, etc.Examples of diisocyanates include isophorone diisocyanate, methaxylylene diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,5-naphthylene diisocyanate, 1,4-phenylene diisocyanate, diphenylmethane-4,4'-diisocyanate, 2,2'-dimethyldiphenylmethane-4,4'-diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, etc. Examples of the above-mentioned monoamine compounds include butylamine, isobutylamine, sec-butylamine, 1,2-dimethylpropylamine, hexylamine, 2-ethylhexylamine, benzylamine, cyclohexylamine, etc. Examples of the above-mentioned diamine compounds include methaxylenediamine, 1,3-bisaminomethylcyclohexane, isophoronediamine, diaminocyclohexane, phenylenediamine, toluenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, hexamethylenediamine, ethylenediamine, propylenediamine, diaminobutane, 1,12-dodecanediamine, piperazine, N-aminoethylpiperazine, etc.

[0019] The tertiary amine adduct-based latent curing agent may be surface-treated, and isocyanate compounds, acidic compounds, etc., are preferably used for the surface treatment. Isocyanate compounds that can be used as agents for the above-mentioned surface treatment include, for example, monofunctional isocyanate compounds such as n-butyl isocyanate, isopropyl isocyanate, phenyl isocyanate, benzyl isocyanate, etc.; polyfunctional isocyanate compounds such as hexamethylene diisocyanate, tolylene diisocyanate, 1,5-naphthalene diisocyanate, diphenylmethane-4,4'-diisocyanate, isophorone diisocyanate, xylylene diisocyanate, paraphenylene diisocyanate, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, etc.; and compounds having isocyanate groups as terminal groups obtained by a reaction between one of the above-mentioned multifunctional isocyanate compounds and a compound containing active hydrogen, etc.As preferred examples of the above-mentioned compounds having isocyanate groups as terminal groups, there may be mentioned, among others, an adduct having isocyanate groups as terminal groups obtained by a reaction between tolylene diisocyanate and trimethylolpropane, an adduct having an isocyanate group as terminal group obtained by a reaction between tolylene diisocyanate and pentaerythritol, etc.

[0020] Preferred examples of acidic compounds that can be used as the above-mentioned surface treatment agents include gases and liquids of inorganic acids and organic acids, respectively. Among the above-mentioned acidic compounds, for example, carbon dioxide (gas), sulfur dioxide (gas), sulfuric acid, hydrochloric acid, oxalic acid, phosphoric acid, acetic acid, formic acid, propionic acid, adipic acid, caproic acid (hexanoic acid), lactic acid, succinic acid, tartaric acid, sebacic acid, p-toluenesulfonic acid, salicylic acid, boric acid, tannin, alginic acid, polyacrylic acid, polymethacrylic acid, phenol, pyrogallol, phenolic resin, resorcinol resin, etc.

[0021] A tertiary amine adduct-based latent curing agent can be easily prepared by a method in which one of the above-mentioned compounds having(s) a tertiary amino group and an epoxy compound, and optionally another component, are mixed, reacted at a temperature of room temperature (25°C) to 250°C, then solidified and ground, or by reacting the above-mentioned mixed components in a solvent such as methyl ethyl ketone, dioxane, tetrahydrofuran, etc., and after removing the solvent, the remaining solids are solidified. The surface treatment of the above-mentioned reaction product can be carried out by bringing it into contact with the above-mentioned isocyanate compound or acidic compound in a solvent such as methyl ethyl ketone, toluene, etc., or without a solvent. Latent curing agent based on imidazole adduct

[0022] An imidazole adduct-based latent curing agent is a curing agent other than a tertiary amine adduct-based latent curing agent and is a compound obtained by a reaction between an imidazole compound and an epoxy compound.

[0023] Examples of imidazole compounds that can be used are 2-ethyl-4-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazoline, 2,4-dimethylimidazoline, 1-(2-hydroxy-3-phenoxypropyl)-2-methylimidazole, 1-(2-hydroxy-3-phenoxypropyl)-2-ethyl-4-methylimidazole, 1-(2-Hydroxy-3-butoxypropyl)-2-methylimidazole, 1-(2-hydroxy-3-butoxypropyl)-2-ethyl-4-methylimidazole, 1-(2-hydroxy-3-phenoxypropyl)-2-phenylimidazoline, 1-(2-hydroxy-3-butoxypropyl)-2-methylimidazoline etc. can be mentioned.

[0024] As starting materials for the latent curing agent based on imidazole adduct, the above-mentioned imidazole compounds, epoxy compounds, which are also used as starting materials for the latent curing agent based on tertiary amine adduct, and other components if required, can be used.

[0025] The (A) epoxy resin curing agent particles are particles having, for example, an average particle diameter of 0.5 to 12.5 µm. The average particle diameter is preferably 1 to 10 µm, more preferably 1.5 to 7 µm, and even more preferably 2 to 5 µm. In this specification, unless otherwise specified, the average particle diameter means the particle diameter cumulatively 50% from the fine grain size side in a cumulative particle size distribution (i.e., the median diameter). When the average particle diameter of the (A) epoxy resin curing agent particles is 0.5 µm or larger, the coated particles have sufficient latency, so that a reduction in the handling ease of the epoxy resin composition containing the coating particles due to the increase in the viscosity of the epoxy resin composition at normal temperature can be avoided.If the average particle diameter is 12.5 µm or smaller, this epoxy resin composition with coated particles can be used excellently even in narrow gaps. The average particle diameter can be determined using a laser diffraction particle size distribution meter (SALD-2200, manufactured by Shimadzu Corporation).

[0026] The (A) epoxy resin curing agent particles with a desired particle diameter can be obtained by crushing the raw particles of the epoxy resin curing agent with a mill, for example, a jet mill, ball mill, attritor, bead mill, etc., and classifying them by a classifying device such as an air separator, cyclone, sieve, etc.

[0027] Furthermore, from the viewpoint of use as a curing agent, the ratio d90 / d50 of the (A) epoxy resin curing agent particles is preferably from 1.0 to 4.0, more preferably 1.0 to 3.0, where d50 and d90 denote the particle diameters at cumulative 50% and cumulative 90% from the fine grain size side in the cumulative particle size distribution.

[0028] The specific surface area of the (A) epoxy resin curing agent particles should preferably be from 0.1 to 10m in terms of the dispersibility of the coated particles in the epoxy resin. 2 / g, more preferably from 0.2 to 7.5m 2 / g, and even more preferably from 0.3 to 5m 2 / g. The specific surface area can be calculated using the following formula: Specific surface area [m2 / g] = 6 / / (density) × (average grain size)

[0029] The density can be measured using an Ultra Pycnometer 1000 (Quantachrome Instruments co., Ltd.).

[0030] Commercially available products can be used as (A) epoxy resin curing agent particles. Commercially available epoxy resin hardener particles include, among others, an imidazole adduct-based latent hardener (e.g., AJICURE PN-23, AJICURE PN-23J, AJICURE PN-31, AJICURE PN-31J, AJICURE PN-40, AJICURE PN-40J, AJICURE PN-50, AJICURE PN-50J, AJICURE PN-H, manufactured by Ajinomoto Fine-Techno Co., Inc.; Adeka Hardener EH3293S, Adeka Hardener EH3366S, Adeka Hardener EH4346S, manufactured by ADEKA CORPORATION, Sunmide LH-210, manufactured by Air Products Japan, Inc.), FXR-1121, manufactured by T&K TOKA Corporation; and the like) and a tertiary amine adduct-based latent curing agent (e.g., AJICURE MY-24, AJICURE MY-25, AJICURE MY-H, AJICURE MY-24J, AJICURE MY-HK-1, manufactured by Ajinomoto Fine-Techno Co., Inc., EH4380S, EH3616S, EH5001P, EH4357S, EH3615S, manufactured by ADEKA CORPORATION, FXR-1020, FXR-1081, manufactured by T&K TOKA Corporation; and the like).

[0031] Based on 100 wt.% of the coated particles, the proportion of (A) epoxy resin curing agent particles should preferably be 71.4 to 99.9 wt.%, more preferably 76.9 to 99.7 wt.%, even further preferably 80.0 to 99.5 wt.% in view of improving acid anhydride resistance and solvent resistance and preventing agglomeration. (B) Alkoxy oligomer

[0032] The (B) alkoxy oligomers which can be used in this invention are not particularly limited and are low molecular weight resins which have both an organic group and an alkoxy group, and as examples thereof, there can be mentioned, among others, alkoxysilyl resins having methyl group(s), alkoxysilyl resins having phenyl group(s), alkoxysilyl resins having epoxy group(s), alkoxysilyl resins having mercapto group(s), alkoxysilyl resins having amino group(s), alkoxysilyl resins having acrylic group(s), alkoxysilyl resins having methacrylic group(s), alkoxysilyl resins having ureido group(s), alkoxysilyl resins having isocyanate group(s), alkoxysilyl resins having vinyl group(s). Of these, alkoxysilyl resins with (an) epoxy group(s), alkoxysilyl resins with mercapto group(s) and alkoxysilyl resins with amino group(s) are particularly suitable.

[0033] The above-mentioned resins can be used individually or in combination with two or more types. The alkoxy oligomer can contain one or two or more organic groups.

[0034] Specifically, as examples of the (B) alkoxy oligomers, alkoxysilyl resins having (a) glycidoxypropyl group(s), alkoxysilyl resins having aminopropyl group(s), alkoxysilyl resins having N-2-(aminoethyl)-3-aminopropyl group(s), alkoxysilyl resins having N-phenyl-3-aminopropyl group(s), alkoxysilyl resins having methacryloxypropyl group(s), alkoxysilyl resins having acryloxypropyl group(s), alkoxysilyl resins having mercaptopropyl group(s), alkoxysilyl resins having ureidopropyl group(s) and alkoxysilyl resins having isocyanatopropyl group(s) can be mentioned, and of these, alkoxysilyl resins having (a) glycidoxypropyl group(s), alkoxysilyl resins having 3-aminopropyl group(s), alkoxysilyl resins having N-2-(aminoethyl)-3-aminopropyl group(s), Alkoxysilyl resins with N-phenyl-3-aminopropyl group(s) and alkoxysilyl resins with mercaptopropyl group(s) are preferred.

[0035] More specifically, examples of the (B) alkoxy oligomers are methoxysilyl resins having (a) glycidoxypropyl group(s), methoxysilyl resins having aminopropyl group(s), ethoxysilyl resins having aminopropyl group(s), methoxysilyl resins having N-2-(aminoethyl)-3-aminopropyl group(s), methoxysilyl resins having N-phenyl-3-aminopropyl group(s), methoxysilyl resins having methacryloxypropyl group(s), methoxysilyl resins having acryloxypropyl group(s), methoxysilyl resins having mercaptopropyl group(s), ethoxysilyl resins having ureidopropyl group(s) and ethoxysilyl resins having isocyanatopropyl group(s), and of these, methoxysilyl resins having (a) glycidoxypropyl group(s), methoxysilyl resins having aminopropyl group(s), ethoxysilyl resins having aminopropyl group(s), methoxysilyl resins having N-2-(aminoethyl)-3-aminopropyl group(s), methoxysilyl resins with N-phenyl-3-aminopropyl group(s) and methoxysilyl resins with mercaptopropyl group(s) are preferred.

[0036] More specifically, the (B) alkoxy oligomer can be represented by the structure of the following general formula (1):

[0037] In formula (1), R1, R2, and R3 are each independently a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, preferably a straight-chain or branched-chain alkyl group having 1 to 5 carbon atoms, more preferably a straight-chain or branched-chain alkyl group having 1 to 4 carbon atoms, even more preferably a methyl group, ethyl group, propyl group, isopropyl group, 1-methylpropyl group, butyl group, isobutyl group, or tert-butyl group, even more preferably a methyl group, ethyl group, propyl group, or isopropyl group, especially a methyl group or ethyl group. The multiple R3s present may be identical or different.

[0038] In formula (1), X is a lower alkyl group, glycidoxyalkyl group, aminoalkyl group, mercaptoalkyl group, acryloxyalkyl group, methacryloxyalkyl group, ureidoalkyl group, isocyanatoalkyl group, or vinylalkyl group, preferably a glycidoxyalkyl group, aminopropyl group, N-2-(aminoethyl)-3-aminopropyl, N-phenyl-3-aminopropyl group, methacryloxypropyl group, acryloxypropyl group, mercaptopropyl group, ureidopropyl group, or isocyanatopropyl group, and more preferably a glycidoxyalkyl group, 3-aminopropyl group, N-2-(aminoethyl)-3-aminopropyl, N-phenyl-3-aminopropyl group, or methacryloxypropyl group. X may include one or more types. That is, the multiple Xs may be identical or different.

[0039] In the formula (1), n is an integer of 2 to 10, preferably 2 to 8, more preferably 2 to 6, and even more preferably 3 to 5.

[0040] The weight-average molecular weight of the (B) alkoxy oligomer is preferably from 350 to 20,000, more preferably from 400 to 15,000, and even more preferably from 500 to 10,000, in view of reducing volatility and thus improving handling, improving dispersibility, and reducing the amount of alcohol by-produced by hydrolysis. The weight-average molecular weight in this invention is determined by the gel permeation chromatography (GPC) method (converted to polystyrene). In the GPC method, measurement is performed at a column temperature of 40°C using Shodex GPC-101 manufactured by Showa Denko KK as the column and using THF or the like as the mobile phase, and then the average molecular weight is calculated from a calibration curve of standard polystyrene obtained in the measurement.

[0041] The viscosity (25°C) of (B) alkoxy oligomer should preferably be 10 mm to avoid evaporation and thus improve handling. 2 / s or more, more preferably 11mm 2 / s or more, and even more preferably 12mm 2 / s or more. On the other hand, in order to ensure efficient coverage of the epoxy resin hardener particles, it should preferably be 200mm 2 / s or less, more preferably 150mm 2 / s or less, and more preferably 100mm 2 / s or less. The viscosity (25°C) in this invention can be determined using an E-type viscosity measuring device (RE-80, manufactured by Toki Sangyo Co., Ltd.) by introducing approximately 0.2 ml of alkoxy oligomer sample taken by syringe into the viscometer in which the temperature is set at 25°C, and measuring at a rotation speed of 5 to 20 rpm.

[0042] Based on 100 wt% of the (B) alkoxy oligomer, the proportion of SiO2 in the (B) alkoxy oligomer should preferably be 10 to 90 wt%, more preferably 20 to 80 wt%, even further preferably 30 to 75 wt% in view of improving the acid anhydride resistance and the solvent resistance.

[0043] The production method of alkoxy oligomer is not particularly limited and can be produced by a known method, for example, as disclosed in Japanese Patent No. 3474007. Specifically, the alkoxy oligomer can be obtained by a reaction in which the alkoxy groups of the silane coupling agent, which is a monomer, are partially hydrolyzed and condensation polymerized. For example, a silane coupling agent and an organic solvent are added to a reaction vessel, and hydrolysis and condensation reactions are carried out at a temperature of 20 to 80°C for 0.1 to 10 hours. An aqueous solution of hydrochloric acid, a fluorine-containing compound, or the like can be used as a catalyst.After the reaction, the catalyst is removed by filtration after removing the alcohol by-product, or by washing with water after switching to a highly hydrophobic organic solvent. For traces of water in the product, a well-known post-treatment method can be used, such as removal with a desiccant or azeotropic dehydration followed by solvent evaporation.

[0044] As the alkoxy oligomer, a commercially available product can be used, and examples of the commercially available alkoxy oligomers include alkoxysilyl resin having(s) epoxy group(s) ("X-41-1053" and "X-41-1059A", manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin having(s) methyl group(s) and epoxy group(s) ("X-41-1056", manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin having(s) primary amino group(s) ("X-40-2651", manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin having(s) aminophenyl group(s) ("X-40-9281", manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin having(s) mercapto group(s) ("X-41-1805", “X-40-1805”, “X-41-1818”, manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin having methyl group / s and mercapto group / s (“X-41-1810”, manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin having methyl group / s and amino group / s (“X-40-2651”, manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin with methyl group / s and methacrylic group / s (“X-40-2655A”, manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin with methyl group / s and acrylic group / s (“KR-513”, manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin with methyl group / s (“KC-89S”, “KR-500”, “X-40-9225”, “X-40-9246”, “X-40-9250”, manufactured by Shin-Etsu Chemical Co., Ltd.), alkoxysilyl resin with methyl group / s and phenyl group / s (“KR-401N”, “X-40-9227”, “X-40-9247”, “KR-510”, “KR-9218”, “KR-213”, manufactured by Shin-Etsu Chemical Co., Ltd.).

[0045] Based on 100 wt% of the coated particles, the proportion of (B) alkoxy oligomer contained in the coated particles should preferably be 0.1 to 40 wt%, more preferably 0.3 to 30 wt%, even further preferably 0.5 to 20 wt%, in view of improving acid anhydride resistance and solvent resistance and preventing agglomeration.

[0046] Based on 100 wt% of the (A) epoxy resin curing agent particles, the proportion of (B) alkoxy oligomer should preferably be 0.1 to 40 wt%, more preferably 0.2 to 30 wt%, even further preferably 0.4 to 25 wt% in view of improving acid anhydride resistance and solvent resistance and preventing agglomeration.

[0047] The average particle diameter D of the coated particles of the epoxy resin composition of the present invention should preferably be 2.5 µm ≤ D ≤ 12.5 µm, more preferably 2.5 µm ≤ D ≤ 10 µm, and even further preferably 2.5 µm ≤ D ≤ 8.5 from the viewpoint of use in narrow gaps when using the coated particles in an epoxy resin composition or from the viewpoint of viscosity increase when using the coated particles in an epoxy resin composition. The average particle diameter can be measured using a commercially available laser diffraction particle size distribution measuring device (e.g., SALD-2200, manufactured by Shimadzu Corporation).

[0048] In the coated particles, the proportion of (B) alkoxy oligomer per unit surface area of (A) epoxy resin curing agent particles should preferably be 0.5 mg / m 2or more, more preferably 1.5 mg / m 2 or more, more preferably 2.5 mg / m 2 or more. Furthermore, the proportion of (B) alkoxy oligomer per unit surface area of (A) epoxy resin curing agent particles should preferably be 150 mg / m 2 or less, more preferably 130 mg / m 2 or less, more preferably 110 mg / m 2 or less.

[0049] Based on 100 wt% of the coated particles, the content of SiO2 in the coated particles is preferably 0.04 to 11 wt%, more preferably 0.12 to 9 wt%, and even more preferably 0.2 to 6.5 wt%, from the viewpoint of improving acid anhydride resistance and solvent resistance. The amount of SiO2 can be measured, for example, by the following method.

[0050] The coated particles are first thoroughly washed with hexane and then dried under reduced pressure to obtain the washed coated particles. 500 mg of the washed coated particles are heated in an electric furnace at a temperature of 660°C for 2 hours. The SiO2 content (wt%) based on 100 wt% of the coated particles is calculated from the weight of SiO2 obtained as ash.

[0051] There is no particular limitation on the production methods of the coated particles. For example, the coated particles can be produced by fully mixing (A) epoxy resin curing agent particles and (B) alkoxy oligomer. For example, the coated particles can be produced using a mixer in a process comprising: preliminarily mixing the (A) epoxy resin curing agent particles for 30 seconds to 5 minutes, preferably 1 to 3 minutes; adding the (B) alkoxy oligomer over a period of, for example, 1 to 5 minutes or preferably 2 to 4 minutes; and then mixing for, for example, 1 to 10 minutes, preferably 2 to 8 minutes.

[0052] The epoxy resin composition of the invention can be obtained by mixing the coated particles with an epoxy resin. Epoxy resin

[0053] The epoxy equivalent of the epoxy resin contained in the epoxy resin composition is, for example, preferably 50 to 1000, more preferably 100 to 800, and even more preferably 150 to 600. When the epoxy equivalent of the epoxy resin is 50 or more, the epoxy resin composition is advantageous because, due to low volatility, the viscosity does not become too low, but remains at an easy-to-handle level. When the epoxy equivalent of the epoxy resin is 1000 or less, the viscosity is not too high, which is favorable in terms of easy handling. Epoxy equivalent here means the mass of the epoxy resin containing 1 equivalent of epoxy groups, and this can be measured, for example, according to JIS K 7236 (2009).

[0054] As the epoxy resin, from the viewpoint of high heat resistance and low moisture permeability or the like, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol E type epoxy resins, bisphenol S type epoxy resins, bisphenol AF type epoxy resins, trisphenol type epoxy resins, biphenyl type epoxy resins, naphthol type epoxy resins, naphthalene type epoxy resins, phenol novolak type epoxy resins, cresol novolak type epoxy resins, bisphenol A novolak type epoxy resins, naphthol novolak type epoxy resins, anthracene type epoxy resins, butadiene structure epoxy resins, biphenyl aralkyl type epoxy resins, Phenolaralkyl-type epoxy resins, glycidylamine-type epoxy resins, such as aromatic glycidylamine-type epoxy resin, etc., phosphorus-containing epoxy resins, alicyclic epoxy resins, aliphatic epoxy resins, epoxy resins with dicyclopentadiene structure, glycidyl ethers of bisphenol, glycidyl ethers of naphthalenediol, glycidyl ethers of phenol types and glycidyl ethers of alcohol types and alkyl substitution products of these resins, haloids and hydrides of these resins, more preferably bisphenol A type epoxy resins and bisphenol F type epoxy resins, even more preferably bisphenol A type epoxy resin.

[0055] As concrete examples of the resins, there can be mentioned, for example, biphenol A type epoxy resins (“jER828EL”, “jER827”, “JER1001”, manufactured by Mitsubishi Chemical Corporation), biphenol F type epoxy resin (“jER807”, manufactured by Mitsubishi Chemical Corporation), biphenol AF type epoxy resin (“ZX1059”, manufactured by Tohto Kasei Co., Ltd.)), naphthalene-type epoxy resin (“HP-4700”, “HP-5000”, manufactured by DIC Corporation), phenol novolak-type epoxy resin (“N-770”, manufactured by DIC Corporation), glycidylamine-type epoxy resin (“jER630”, manufactured by Mitsubishi Chemical Corporation), cresol novolak-type epoxy resin (“N-695”, manufactured by DIC Corporation), alicyclic epoxy resin (“CEL2021P”, manufactured by Daicel Corporation), hydrogenated structure epoxy resin (“YX8000”, manufactured by Mitsubishi Chemical Corporation), dicyclopentadiene-type (multifunctional) epoxy resin (“HP7200”, manufactured by DIC Corporation), butadiene structure epoxy resin (“PB-3600”, manufactured by Daicel Corporation), biphenyl structure epoxy resin (“NC3000H”, “NC3000L”, manufactured by Nippon Kayaku Co., Ltd., and “YX4000” manufactured by Mitsubishi Chemical Corporation), aliphatic epoxy resin (“EX-216L” manufactured by Nagase ChemteX Corporation), etc.

[0056] The epoxy resin can be liquid or solid. The epoxy resin can also be a mixture of a liquid resin and a solid resin. The definitions of "liquid" and "solid" refer to the state of the epoxy resin at normal temperature (25°C). Regarding applicability, processability, and adhesive properties, for example, 10% by weight of the total epoxy resin to be used is liquid epoxy resin.

[0057] Preferred liquid epoxy resins are: bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AF type epoxy resins, naphthalene type epoxy resins, glycidyl ester type epoxy resins, phenol novolak type epoxy resins, alicyclic epoxy resins with ester skeleton and epoxy resins with butadiene structure. As concrete examples of the liquid epoxy resins, there can be mentioned “HP4032”, “HP4032D”, “HP4032SS” (naphthalene type epoxy resin) manufactured by DIC Corporation, “828US”, “JER828EL” (bisphenol A type epoxy resin), “JER807” (bisphenol F type epoxy resin), “JER152” (phenol novolak type epoxy resin) and “YL7760” (bisphenol AF type epoxy resin) manufactured by Mitubishi Chemical Corporation, “ZX1059” (mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by NIPPON STEEL & SUMIKIN CHEMICAL CO.,LTD."EX-721" (glycidyl ester-type epoxy resin) manufactured by Nagase ChemteX Corporation, "Celoxide 2021P" (alicyclic ester-type epoxy resin), and "PB-3600" (butadiene-type epoxy resin) manufactured by Daicel Corporation. These resins can be used individually or in combination with two or more.

[0058] Preferred solid epoxy resins are tetrafunctional naphthalene-type epoxy resins, cresol novolak-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol-type epoxy resins, bisphenyl-type epoxy resins, naphthylene ether-type epoxy resins, anthracene-type epoxy resins, bisphenol A-type epoxy resins and tetraphenylethane-type epoxy resins. As concrete examples of the solid epoxy resins, "HP4032H" (naphthalene type epoxy resin), "HP-4700", "HP-4710" (tetrafunctional naphthalene type epoxy resins), "N-690" (cresol novolak type epoxy resin), "N-695" (cresol novolak type epoxy resin), "HP-7200" (dicyclopentadiene type epoxy resin), "HP-7200HH", "EXA 7311", "EXA7311-G3", "EXA7311-G4", "EXA7311-G4S", "HP6000" (naphthylene ether type epoxy resins) manufactured by DIC Corporation, "EPPN-502H" (trisphenol type epoxy resin), "NC7000L" (Naphthol novolak type epoxy resin), "NC3000H", "NC3000", "NC3000L", "NC3100" (Biphenyl type epoxy resins), manufactured by NIPPON KAYAKU Co.,Ltd., "ESN475V" (naphthol-type epoxy resin), "ESN485" (naphthol novolak-type epoxy resin), manufactured by NIPPON STEEL & SUMIKIN CHEMICAL CO., LTD., "YX4000H", "YL6121" (biphenyl-type epoxy resin), "YX4000HK" (bixylenol-type epoxy resin), "YX8800" (anthracene-type epoxy resin), manufactured by Mitsubishi Chemical Corporation, "PG-100" and "CG-500" manufactured by Osaka Gas Chemicals Co., Ltd., "YL7800" (fluorene-type epoxy resin), manufactured by Mitsubishi Chemical Corporation, and "jER1010" (solid bisphenol A-type epoxy resin), "jER1031S" (Tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical Corporation and the like.

[0059] The epoxy resin compositions contain the coated particles in an amount of preferably 0.1 to 50 wt%, more preferably 0.3 to 40 wt%, and even more preferably 0.5 to 30 wt%. When the proportion of the coated particles is 0.1 wt% or more, curing proceeds more rapidly and the curing time is shortened. When the proportion of the coated particles is 50 wt% or less, the resin composition exhibits sufficient acid anhydride resistance and solvent resistance.

[0060] A resin composition according to the invention may further contain at least one component(s) selected from the group consisting of curing agents, curing accelerators, thermosetting resins, thermoplastic resins, inorganic fillers, organic fillers, thickeners, defoamers, leveling agents, coupling agents, colorants and organic solvents.

[0061] The curing agents just mentioned are, for example, epoxy resin curing agents which do not belong to the coated particles of the epoxy resin composition of the present invention, and as examples thereof, acid anhydride compounds, thiol compounds, guanidine compounds, hydrazide compounds, phenol compounds, naphthol compounds, active ester compounds, benzoxazine compounds, cyanate ester compounds, carbodiimide compounds and the like can be mentioned.

[0062] The thiol compounds are e.g. Thiol compounds which can be obtained from an esterification between polyols and organic acid of mercapto, such as: B. Trimethylolpropane tris(thioglycollate), pentaerythritol tetrakis(thioglycolate), ethylene glycol dithioglycolate, trimethylolpropane tris(3-mercaptopropionate), trimethylolpropane tris((3-thiopropionate), pentaerythritol tetrakis(β-thiopropionate) or dipentaerythritol poly(β-thiopropionate) etc.; alkylpolythiol compounds such as 1,4-butanedithiol, 1,6-hexanedithiol, 1,10-decanedithiol etc., polyethers with a thiol end group; polythioethers with a thiol end group; thiol compounds each obtained by a reaction between epoxy compounds and hydrogen sulfide; thiol compounds with a thiol end group obtained by a reaction between polythiol compounds and epoxy compounds; etc.

[0063] Examples of acid anhydrides include tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, methylbicyclo[2.2.1]heptane-2,3-dicarboxylic anhydride, tetrapropenylsuccinic anhydride (3-dodecenylsuccinic anhydride), octenylsuccinic anhydride, ethylene glycol bistrimellitate anhydride, methylenedomethylenetetrahydrophthalic anhydride, 3,4-dimethyl-6-(2-methyl-1-propenyl)-4-cyclohexene-1,2-dicarboxylic anhydride, a mixture of any of the above compounds and 1-isopropyl-4-methylbicyclo[2.2.2]octa-5-ene-2,3-dicarboxylic anhydride, etc. Commercially available acid anhydrides include HN-2200 (methyltetrahydrophthalic anhydride) and HN-5500 (methyltetrahydrophthalic anhydride) from Hitachi Chemical Co., Ltd.

[0064] Examples of guanidine compounds include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]deca-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-Phenylbiguanide, 1-(o-tolyl)biguanide, etc. can be mentioned. Preferred guanidine compounds include dicyandiamide, 1-(o-tolyl)biguanide, etc., and dicyandiamide is particularly suitable. Commercially available guanidine compounds include "jER CURE DICY-7" (dicyandiamide) manufactured by Japan Epoxy Resin Co., Ltd., "NOCCELER BG" (1-(o-tolyl)biguanide) manufactured by Ouchi Shinko Chemical Industrial Co., Ltd., etc.

[0065] Examples of the hydrazide compounds include carbohydrazide, oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, iminodiacetic acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide, dodecane dihydrazide, hexadecane dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, diglycolic acid dihydrazide, tartaric acid dihydrazide, malic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, 2,6-naphthoic acid dihydrazide, 4,4'-bisbenzene dihydrazide, 1,4-naphthoic acid dihydrazide, naphthalene-2,6-dicarbohydrazide, 3-hydroxy-2-naphthoic acid hydrazide, Citric acid trihydrazide, etc. Commercially available hydrazide compounds include, for example, "AJICURE VDH," "AJICURE UDH," manufactured by Ajinomoto Fine-Techno Co., Ltd., etc.

[0066] As concrete examples of the phenol compounds and naphthol compounds, there can be mentioned, for example, “MEH-7700”, “MEH-7810”, “MEH-7851” manufactured by Meiwa Plastic Industries, Ltd., “NHN”, “CBN” and “GPH” manufactured by Nippon Kayaku co., Ltd., “SN170”, “SN180”, “SN190”, “SN475”, “SN485”, “SN495”, “SN375” and “SN395” manufactured by NIPPON STEEL & SUMIKIN CHEMICAL CO., LTD., “LA7052”, “LA7054”, “LA3018”, “EXB-9500” and “TD2090” manufactured by DIC Corporation, and the like.

[0067] The active ester compounds are not particularly limited. However, in general, compounds having two or more ester groups with high reactivity in one molecule are preferably used, such as phenol esters, thiophenol esters, N-hydroxyamine esters, esters of heterocyclic hydroxy compounds, etc. Preferred active ester compounds are compounds obtained by a condensation reaction between carboxylic acid compounds and / or thiocarboxylic acid compounds and hydroxy compounds and / or thiol compounds. Specifically, preferred active ester compounds are those having a dicyclopentadiene-type diphenol structure, active ester compounds having a naphthalene structure, active ester compounds containing an acetylation product of phenol novolak, and active ester compounds containing a benzoylation product of phenol novolak.A "dicyclopentadiene-type diphenol structure" is a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene. Commercially available active ester compounds include "EXB9451," "EXB9460," "EXB9460S," and "HPC-8000-65T" (manufactured by DIC Corporation) as an active ester compound with a dicyclopentadiene-type diphenol structure; "EXB9416-70BK" (manufactured by DIC Corporation) as an active ester compound with a naphthalene structure; "DC808" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound with an acetylation product of phenol novolak; and "YLH1026" (manufactured by Mitsubishi Chemical Corporation) as an active ester compound with a benzoylation product of phenol novolak.

[0068] As concrete examples of the benzoxazine compounds, “HFB2006M” manufactured by Showa Highpolymer Co., Ltd., and “Pd” and “Fa” manufactured by Shikoku Chemicals Corporation can be mentioned.

[0069] Examples of cyanate ester compounds include: bifunctional cyanate resins, such as: B. Bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)thioether and bis(4-cyanatephenyl)ether etc., multifunctional cyanate resins which are derivatized from polyphenol novolak and cresol novolak etc., as well as prepolymers in which some of the above-mentioned cyanate resins are triazinated, etc. As concrete examples of the cyanate ester-based curing agents, there can be mentioned “PT30” and “PT60” (both phenol novolac type multifunctional cyanate ester resin) manufactured by Lonza Japan Co., Ltd., “BA230” (part of which is bisphenol A dicyanate and part of which is bisphenol A dicyanate) manufactured by Lonza Japan Co., Ltd.this is completely triazinated to trimeric prepolymer) and the like.

[0070] As concrete examples of the carbodiimide compounds, “V-03”, “V-07” manufactured by Nisshinbo Chemical Inc., and the like can be mentioned.

[0071] Examples of curing accelerators include phosphorus-based curing accelerators, amine-based curing accelerators, imidazole-based curing accelerators, guanidine-based curing accelerators, etc. These curing accelerators can be used individually or in combination of two or more types.

[0072] As examples of the phosphorus-based curing accelerators, there can be mentioned triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoic acid salt, (4-methylphenyl) triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, etc., and of these, triphenylphosphine and tetrabutylphosphonium decanoic acid salt are preferred.

[0073] As amine-based curing accelerators, for example, trialkylamines such as triethylamine, tributylamine, etc., 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol and 1,8-diazabicyclo(5,4,0)-undecene, etc. can be mentioned, and of these, 4-dimethylaminopyridine and 1,8-diazabicyclo(5,4,0)-undecene are preferred.

[0074] Imidazole-based curing accelerators can be, for example, imidazole compounds and adducts of imidazole compounds and epoxy resins, such as:2-Methylimidazol, 2-Undecylimidazol, 2-Heptadecylimidazol, 1,2-Dimethylimidazol, 2-Ethyl-4-methylimidazol, 1,2-Dimethylimidazol, 2-Ethyl-4-methylimidazol, 2-Phenylimidazol, 2-Phenyl-4-methylimidazol, 1-Benzyl-2-methylimidazol, 1-Benzyl-2-Phenylimidazol, 1-Cyanoethyl-2-methylimidazol, 1-Cyanoethyl-2-Undecylimidazol, 1-Cyanoethyl-2-ethyl-4-methylimidazol, 1-Cyanoethyl-2-Phenylimidazol, 1-Cyanoethyl-2-Undecylimidazoliumtrimellitat, 1-Cyanoethyl-2-Phenylimidazoliumtrimellitat, 2,4-Diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazin, 2,4-Diamino-6-[2'-Undecylimidazolyl-(1')]-ethyl-s-triazin, 2,4-Diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazin, 2,4-Diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazinisocyanursäure-Addukt, 2-Phenylimidazolisocyanursäure-Addukt, 2-Phenyl-4,5-Dihydroxymethylimidazol, 2-Phenyl-4-methyl-5hydroxymethylimidazol, 2,3-Dihydro-1H-pyrrolo[1,2-a]benzimidazol, 1-Dodecyl-2-methyl-3-Benzylimidazoliumchlorid, 2-Methylimidazolin, 2-Phenylimidazolin etc., and of these, 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole are preferred.

[0075] As an imidazole-based curing accelerator, a commercially available product can be used, and for this purpose, for example, “P200-H50” manufactured by Mitubishi Chemicals Corporation can be mentioned.

[0076] As the guanidine-based curing accelerator, the same guanidine compounds mentioned above as curing agents can be used, and as examples thereof, there can be mentioned dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]deca-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]deca-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, 1-(o-tolyl)biguanide, etc., and of these, dicyandiamide and 1,5,7-triazabicyclo[4.4.0]deca-5-ene are preferred.

[0077] The amount of curing accelerator in the resin composition is not particularly limited, but it is preferably used in the range of 0.05 wt% to 3 wt%.

[0078] The thermosetting resins are thermosetting resins other than the above-mentioned epoxy resins, and examples of the thermosetting resins are vinylbenzyl compounds, acrylic compounds, maleimide compounds, block isocyanate compounds, etc.

[0079] Examples of thermoplastic resins include phenoxy resin, polyvinyl acetal resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamideimide resin, polyetherimide resin, polysulfone resin, polyethersulfone resin, polyphenylene ether resin, polycarbonate resin, polyetheretherketone resin, polyester resin, etc. Phenoxy resins are preferred. These thermoplastic resins can be used singly or in combination with two or more.

[0080] The average molecular weight of the thermoplastic resins in terms of polystyrene is preferably in the range of 8,000 to 70,000, more preferably 10,000 to 60,000, and even more preferably 20,000 to 60,000. The average molecular weight of the thermoplastic resins in terms of polystyrene is determined by the gel permeation chromatography (GPC) method. Specifically, in the GPC method, determination is carried out at a column temperature of 40°C using LC-9A / RID-60 manufactured by Shimadzu Corporation as the measuring device and using chloroform or the like as the mobile phase, and the average molecular weight of the thermoplastic resins in terms of polystyrene is calculated from a standard polystyrene calibration curve obtained in the determination.

[0081] As the phenoxy resin, for example, there can be mentioned phenoxy resins each having a skeleton selected from a group consisting of, for example, a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a bisphenol acetophenone skeleton, a novolak skeleton, a biphenyl skeleton, a fluorene skeleton, a dicyclopentadienyl skeleton, a norbornene skeleton, a naphthalene skeleton, anthracene skeleton, an adamantane skeleton, a terpene skeleton, and a trimethylcyclohexane skeleton. The terminal group of these phenoxy resins may be a functional group selected from phenolic hydroxy groups, epoxy groups, and the like. These phenoxy resins can be used singly or in combination of two or more types.As concrete examples of the phenoxy resins, there can be mentioned “1256” and “4250” (each a phenoxy resin having a bisphenol A skeleton), “YX8100” (phenoxy resin having a bisphenol S skeleton), and “YX6954” (phenoxy resin having a bisphenol acetophenone skeleton) manufactured by Mitsubishi Chemical Corporation, and further “FX280” and “FX293” manufactured by NIPPON STEEL & SUMIKIN CHEMICAL CO., LTD; and “YL6954BH30”, “YX7553”, “YL7769BH30”, “YL6794”, “YL 7213”, “YL7290”, and “YL7482” manufactured by Mitsubishi Chemical Corporation, and the like.

[0082] Examples of polyvinyl acetal resins include polyvinyl formal resins and polyvinyl butyral resins, of which polyvinyl butyral resins are preferred. Specific examples of polyvinyl acetal resins include "Denka butyral 4000-2," "Denka butyral 5000-A," "Denka butyral 6000-C," and "Denka butyral 6000-EP" manufactured by Denki Kagaku Kogyo Co., Ltd., as well as "S-REC BH Series, BX Series, KS Series, BL Series, and BM Series" manufactured by Sekisui Chemical Co., Ltd., and the like.

[0083] As concrete examples of polyimide resins, “RIKACOAT SN20” and “RIKACOAT PN20” manufactured by New Japan Chemical Co., Ltd. can be mentioned.

[0084] Specific examples of polyamideimide resins include "VYLOMAX HR11NN" and "VYLOMAX HR16NN" manufactured by Toyobo Co., Ltd., and the like. Further, as concrete examples of polyamideimide resins, modified polyamideimides such as "KS9100" and "KS9300" (polyamideimide with polysiloxane backbone) manufactured by Hitachi Chemical Co., Ltd.

[0085] As concrete examples of the polyethersulfone resins, “PES5003P” manufactured by Sumitomo Chemical Co., Ltd. and the like can be mentioned.

[0086] As concrete examples of polysulfone resins, polysulfone “P1700” and “P3500” manufactured by Solvay Advanced Polymers KK can be mentioned.

[0087] The proportion of thermoplastic resins in the resin composition is preferably from 0.1 wt% to 20 wt%, more preferably from 0.5 wt% to 10 wt%, further preferably from 1 wt% to 5 wt%.

[0088] The materials for the inorganic fillers are not particularly limited, and examples include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, as well as phosphoric acid zirconium tungstate, iron, iron oxide, ferrite, alloys, other electrically conductive fillers, magnetic fillers, thermally conductive fillers, etc.As an embodiment of the invention, an epoxy resin composition is suitable which contains one or more fillers selected from the group consisting of silicon dioxide, electrically conductive fillers, magnetic fillers and thermally conductive fillers.

[0089] Concretely, the silica used includes amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. Spherical silica is preferred. The average particle size is not particularly limited, but is preferably 600 nm or smaller, more preferably 300 nm or smaller, and further preferably 200 nm or smaller. The lower limit of the average particle size is not particularly limited, but is preferably 5 nm or larger. Commercially available products include "SO-C2," "SO-C1," and "SO-C4" manufactured by Admatechs Company Limited. The average particle size of the inorganic fillers can be measured using the laser diffraction scattering method according to the Mie scattering theory.

[0090] Examples of electrically conductive fillers include solder particles, nickel particles, nano-sized metal crystals, metal particles with a metal surface coated with another metal, and metal particles such as gradient particles of copper and silver. These include, for example, hard particles made of styrene resin, urethane resin, melamine resin, epoxy resin, acrylic resin, phenolic resin, styrene-butadiene resin, etc., coated with a thin electrically conductive layer of, for example, gold, nickel, silver, copper, solder, etc. Electrically conductive fillers are generally spherical microparticles measuring approximately 1 to 20 µm.

[0091] Specific magnetic fillers include: pure iron powder, Fe alloys such as Fe-Si alloy powder, Fe-Si-Al alloy powder, Fe-Ni alloy powder, Fe-Ni-Mo alloy powder, Fe-Ni-Mo-Cu alloy powder, Fe-Co alloy powder, Fe-Ni-Co alloy powder, Fe-Cr alloy powder, Fe-Cr-Si alloy powder, Fe-Ni-Cr alloy powder or Fe-Cr-Al alloy powder; amorphous alloys such as Fe-based amorphous alloy, Co-based amorphous alloy, spinel type ferrites such as Ni-Ni alloy powder, Ni-Ni-Ni alloy powder, and Fe-Cr-Al alloy powder. B. Mg-Zn-based ferrite, Mn-Zn-based ferrite, Mn-Mg-based ferrite, Cu-Zn-based ferrite, Mg-Mn-Sr-based ferrite, Ni-Zn-based ferrite, etc.; hexagonal ferrites, such asBa-Zn-based ferrite, Ba-Mg-based ferrite, Ba-Ni-based ferrite, Ba-Co-based ferrite, Ba-Ni-Co-based ferrite; and garnet-type ferrites such as Y-ferrite.

[0092] Specific thermally conductive materials include fillers made of aluminum nitride, aluminum oxide, boron nitride, silicon nitride, graphite powder, and silicon carbide. A commercially available aluminum nitride product, for example, is "Shapal H," manufactured by Tokuyama Corporation, and a commercially available silicon nitride product, for example, is "SN-9S," manufactured by Denki Kagaku Kogyo Co., Ltd. Commercially available aluminum oxide products include "AHP300," manufactured by Nippon Light Metal Co., Ltd., and "ALUNABEADSO." ® CB” (for example, “CB-P05”, “CB-A30S”) manufactured by Showa Denko KK, and “DAW-45”, “DAW-05” and “ASFP-20” manufactured by Denky Company Limited, and the like.

[0093] Examples of organic fillers include silicone powder, nylon powder, fluorine powder, acrylic rubber particles, polyamide fine particles, silicone particles, etc. Specific examples of acrylic rubber particles include any particles in which the fine particles are made of a resin exhibiting rubber elasticity, such as acrylonitrile butadiene rubber, butadiene rubber, acrylic rubber, etc., and are made insoluble and unbondable with an organic solvent by chemical crosslinking. Specific examples of organic fillers include XER-91 (manufactured by JSR Corporation), Staphyloid AC3355, AC3816, AC3832, AC4030, AC3364, IM101 (all manufactured by Aica Kogyo Co., Ltd.), Paraloid EXL2655 and EXL2602 (manufactured by Kureha Chemical Kogyo Co., Ltd.), and the like.Specific examples of polyamide fine particles may be fine particles with a size of 50 µm or smaller and made of resins containing an amide bond, such as aliphatic polyamides such as nylon, aromatic polyamides such as Kevlar, and polyamide-imide. Specific examples include VESTOSINT 2070 (manufactured by Daicel Hüls Co., Ltd.), SP500 (manufactured by Toray Industries, Inc.), and the like.

[0094] Thickeners such as Orben, Benton, etc. can be mentioned.

[0095] Examples of defoamers include silicone-based defoamers, fluorine-based defoamers, polymeric defoamers, and the like.

[0096] Commercially available surfactants such as silicone-based, fluorine-based, or ester-based surfactants, cationic, anionic, nonionic, and amphoteric surfactants can be used as leveling agents. These can be used singly or in combination of two or more. Examples of the above-mentioned surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyethylene glycol diesters, sorbitan fatty acid esters, fatty acid-modified polyesters, tertiary amine-modified polyurethanes, polyethyleneimines, and the like. More specifically, product names of the surfactants are KP (manufactured by Shin-Etsu Chemical Co., Ltd.), Polyflow (manufactured by Kyoeisha Chemical Co., Ltd.), EFTOP (manufactured by Mitsubishi Materials Electronic Materials Co., Ltd.), MEGAFACE (manufactured by DIC Corporation), Fluorad (manufactured by Sumitomo 3M Limited), Asahi Guard (manufactured by Asahi Glass Co., Ltd.), Surflon (manufactured by AGC Seimi Chemical Co., Ltd.), Solsperse (manufactured by Zeneca, Inc.), EFKA (manufactured by CIBA AG), AJISPER (manufactured by Ajinomoto Fine Techno Co., Inc.) and the like.

[0097] Examples of adhesion promoters include imidazole-based, thiazole-based, triazole-based, etc. Specifically, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, etc.

[0098] Examples of colorants include phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, carbon black, etc.

[0099] Examples of organic solvents include ketones such as acetone, methyl ethyl ketone (MEK), and cyclohexanone; acetic acid esters such as ethyl acetate, butyl acetate, Cellosolv acetate, propylene glycol monomethyl ethyl acetate, and carbitol acetate; carbitols such as Cellosolv and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; amide-based solvents such as dimethylformamide, dimethylacetoamide (DMAc), and N-methylpyrrolidone, and the like. The above-mentioned organic solvents can be used singly or in combination of two or more.

[0100] An epoxy resin used in the present invention may be liquid, paste-like, or film-like.

[0101] The epoxy resin compositions can be used as epoxy resin material for the fields such as architecture, construction, automotive, ship, aerospace, mechanical engineering, robotics, telecommunications, electrical industry, semiconductors, monitors, etc.

[0102] In particular, it can be used as an adhesive, binder, electrically conductive material, magnetic material, thermally conductive material, insulating material, sealing material, coating material, paints or the like.

[0103] Regarding adhesives and binders, the epoxy resin compositions are suitable as adhesives and sealants for construction and civil engineering, as structural adhesives and binders for automobiles, ships, and aircraft, as assembly adhesives for mechanical engineering and robot assembly, as die bonding materials for assembling electronic components and IC chips, and the like. The adhesives and binders used in the present invention can be used for housings / frames, bodies and chassis of automobiles, ships, and aircraft, for CPUs of PCs, smartphones, and tablets, as well as for spindle motor components for camera modules, communication modules, hard disks, and the like.

[0104] As electrically conductive materials, the epoxy resin compositions preferably contain the above-mentioned electrically conductive fillers. A method for producing these fillers has been proposed, for example, in published Japanese Patent Application H01-113480.

[0105] The electrically conductive materials can be used for the manufacture of electrical devices, integrated circuits, semiconductor devices, passive devices, solar cells, solar modules, and / or light-emitting diodes; for the assembly of chip components of driver ICs, LED elements, etc.; for the assembly of electronic components; and the like. Since both electrical conductivity and insulating properties are imparted, the epoxy resin compositions can also be anisotropic conductive materials.

[0106] As a magnetic material, the epoxy resin compositions should preferably contain a magnetic filler mentioned above.

[0107] The magnetic materials can be used as electromagnetic wave shielding, coil components, inductor elements, electromagnetic wave absorbers, magnetic printing inks, antenna devices, etc.

[0108] As a thermally conductive material, the epoxy resin compositions preferably contain a thermally conductive filler mentioned above. The thermally conductive materials can be used for CPUs, power IC modules, etc. As a manufacturing method for a thermally conductive material, for example, methods disclosed in Japanese Patent Application Laid-Open Nos. H06-136244, H10-237410, 2000-3987, etc. can be mentioned. More specifically, an epoxy resin as a thermosetting resin, a phenol novolak curing agent or thiol compound as a curing agent, and further a thermally conductive filler can be mixed and kneaded homogeneously. By adding the coated particles according to this embodiment to the mixture, a thermally conductive material can be obtained.

[0109] For the insulating materials, it is preferable to use insulating fillers such as silica among the above-mentioned fillers. As a manufacturing method for a film with insulating properties, for example, methods proposed in Japanese Patent Application Laid-Open Nos. S62-141083 and H05-295329 can be used. Specifically, a solution is prepared in which a solid epoxy resin, a liquid epoxy resin, and, if necessary, a solid urethane resin are dissolved, mixed, or dispersed in toluene in a total amount of 50 wt.% based on the total mass of all components, including the solvent. To the resulting solution, the coated particles according to this embodiment are added in an amount of 30 wt.% based on the solution to obtain a varnish in which the coated particles are dispersed.Then, a layer of this varnish is applied to a peelable polyethylene terephthalate substrate, for example, with a thickness of 50µm, so that after drying with toluene, the layer has a thickness of 30µm. After drying with toluene, this layer acquires the ability to remain inactive at ambient temperature, but exhibits adhesive properties upon heating due to the influence of the latent curing agent.

[0110] The insulating materials can be used as insulating adhesive mats, insulating adhesive films, insulating adhesive pastes, insulating pastes, insulating films, insulating mats, insulating paints for electronic or electrical parts, etc. The insulating materials are suitable for applications requiring insulating properties and can thus be used as insulating interlayers or solder resist layers in printed circuit boards and the like.

[0111] Sealing materials include solid sealing materials, liquid sealing materials, film-like sealing materials, and the like. Liquid sealing materials are suitable as underfill materials, potting materials, insulating materials, molding materials, etc. The sealing materials can be used, for example, in a semiconductor package such as a wafer-level package or a BGA (Ball Grid Array) package. As a manufacturing method for a sealing material, methods described in Japanese Patent Application Laid-Open Nos. H05-43661, 2002-226675, etc. can be used. According to these methods, the sealing material can be manufactured as a molding material for sealing and impregnating electrical and electronic components. More specifically, a bisphenol F-type epoxy resin, an aliphatic epoxy resin, acid anhydride curing agents such asa curing agent made of methylhexahydrophthalic anhydride, and spherical quartz glass powder are combined and uniformly mixed, after which the coated particles according to this embodiment are further added and the resulting mixture is further uniformly mixed, so that a sealing material can be obtained.

[0112] As the coating agent, for example, a covering material for flexible printed circuit boards, an interlayer insulating coating material for a printed circuit board, an electromagnetic wave absorbing material, and the like can be mentioned. The coating materials can be used for flexible printed circuit boards, multilayer printed circuit boards, and the like. As the production method of the coating materials, methods have been proposed, for example, in Japanese Examined Patent Publication H04-6116, Japanese Patent Laid-Open Nos. H07-304931, H08-64960, and 2003-246838, etc. Specifically, silica or the like is selected from the above-mentioned fillers as a filler, mixed with a bisphenol A type epoxy resin, a phenoxy resin, a rubber-modified epoxy resin, and the like, and then further mixed with the coated particles of this embodiment.Then, a solution containing the above mixture in a proportion of 50 wt% is prepared using methyl ethyl ketone (MEK). A 50 µm thick layer of this solution is applied to a polyimide film and laminated with a copper foil at 60°C to 150°C, followed by heating and curing at 180°C to 200°C. Thus, a laminate can be obtained in which the epoxy resin composition layer is applied between the layers.

[0113] Examples of paints and colorants include powder paints and the like. These paints can be used for corrosion protection applications, paint applications for the interior and exterior surfaces of pipes / conduits, household applications, electrical and electronic components, automotive parts, and the like.

[0114] As a manufacturing method for paints, methods have been proposed, for example, in Japanese Patent Application Laid-Open Nos. H11-323247 and 2005-113103, etc. Specifically, a bisphenol A type epoxy resin is mixed with titanium dioxide, talc, or the like, and a mixed solvent of methyl isobutyl ketone (MIBK) / xylene = 1 / 1 (wt%) is added thereto, followed by stirring and mixing to obtain a base agent. To this, the coated particles according to this embodiment are added and uniformly dispersed in the base agent to obtain a paint.

[0115] As a further embodiment of the invention, a sheet material containing an epoxy resin composition according to the invention can be provided. The sheet material according to the invention comprises a carrier and a resin composition layer provided on the carrier and containing a resin composition according to the invention. Examples of carriers that can be mentioned are a film made of plastic material, a metal foil, or release paper.

[0116] If a film made of plastic material is to be used as the carrier, the plastic material is, for example, a polyester such as polyethylene terephthalate (abbreviated “PET”), polyethylene naphthalate (abbreviated “PEN”), polycarbonate (abbreviated “PC”), acrylic such as polymethyl methacrylate (PMMA), cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide or the like.

[0117] If metal foil is to be used as the carrier, the metal foil can be copper foil, aluminum foil, or the like, for example, with copper foil being preferred. The copper foil can be a foil made entirely of copper—in other words, a single metal can be used—but it is also possible to use a foil made of an alloy of copper and other metals (e.g., tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium).

[0118] Furthermore, a support in which a release layer is provided on the surface to be bonded with a resin composition layer can also be used as the support.

[0119] The sheet material of the present invention can be produced by, for example, preparing a resin varnish in which a resin composition is dissolved in an organic solvent, then applying this resin varnish to the support using a die coater, and then drying the applied resin to form a resin composition layer. Drying can be carried out by a known method such as heating or blowing with hot air.

[0120] In the layer or sheet material, a protective film serving as a quasi-carrier may be laminated onto the surface of the resin composition layer which has no contact with the carrier (ie the surface on the opposite side of the carrier).

[0121] As a further embodiment of the present invention, composite materials containing the epoxy resin compositions of the present invention can be provided. The composite materials include, for example, composite materials usable in resin transfer molding processes, composite materials usable in filament winding processes, prepregs, and the like.

[0122] A fiber base material for forming the prepreg is not particularly limited, and any common materials commonly used as prepreg base materials, such as glass fabric, carbon fiber, aramid nonwoven fabric, or liquid crystal polymer nonwoven fabric, can be used.

[0123] The prepreg can be produced by a known method such as a hot melt method or solvent method.

[0124] As manufacturing methods for the composite materials, for example, methods described in Japanese Patent Application Laid-Open Nos. 2009-102563, 2010-100730, 2013-18804, etc. are used. Specifically, a bisphenol A type epoxy resin and an acid anhydride curing agent, such as a methylnadic anhydride or methyltetrahydrophthalic anhydride curing agent, are combined and uniformly mixed. Then, the coated particles of the present invention are added to the resulting mixture and uniformly mixed to obtain a resin for composite materials.

[0125] The coated particles of the epoxy resin composition according to the invention have a lower tendency to aggregate and have excellent acid anhydride resistance and solvent resistance.

[0126] The aggregation of coated particles can be evaluated by measuring the average particle diameter of the coated particles. Specifically, when the coated particles aggregate, the resulting average particle diameter becomes larger than the average particle diameter of each coated particle. This is because the particle diameter of each individual coated particle contained in the aggregate is not determined, but the particle diameter of the entire aggregate is measured. The term "less tendency to aggregate" here means that the particles aggregate only slightly upon coating treatment, that is, the difference between the measured values of the average particle diameters of the uncoated epoxy resin curing agent particles and the coated epoxy resin curing agent particles is small.The average particle size D of the coated particles is preferably 1.0 to 5.0 times the average particle size of the (A) epoxy resin curing agent particles before the coating treatment, more preferably 1.0 to 4.0 times, even more preferably 1.1 to 3.0 times. The average particle size D of the coated particles is more preferably 1.0 to 4.0 times, even more preferably 1.0 to 3.0 times the average particle size of the (A) epoxy resin curing agent particles before the coating treatment.

[0127] The acid anhydride resistance of the coated particles can be evaluated, for example, by storing the epoxy resin composition containing the coated particles and acid anhydride under specific conditions and determining the rate of increase in the viscosity of the composition after storage compared to the viscosity of the composition before storage. The viscosity can be measured using a commercially available viscosity measuring device, such as the RE80 viscosity meter (cone rotor: 1.34° x R24, manufactured by Toki Sangyo Co., Ltd.). The lower the viscosity increase rate, the better the acid anhydride resistance.

[0128] The solvent resistance of the coated particles can be evaluated, for example, by storing the epoxy resin composition containing the coated particles and solvent under specific conditions and determining the viscosity increase rate of the composition after storage compared to the viscosity of the composition before storage. The viscosity can be measured using a commercially available viscosity measuring device, such as the RE80 viscosity meter (cone rotor: 1.34° × R24, manufactured by Toki Sangyo Co., Ltd.). The lower the viscosity increase rate, the better the solvent resistance. [Examples]

[0129] In the following, the invention is explained in more detail using exemplary embodiments and comparative examples. Manufacturing example 1

[0130] In a HENSCHEL mixer (FM10C / I, manufactured by Nippon Coke & Engineering Co., Ltd.) whose wall surface temperature was regulated at 40°C, a preliminary mixing of 1000g of imidazole adduct-based latent curing agent (AJICURE PN-50J, manufactured by Ajinomoto Fine Techno Co., Inc.; average particle size = 2.5µm, density = 1.2g / cm 3 , specific surface area = 2.0m 2 / g; d90 / d50 = 1.9) for 2 minutes, and then 200g of alkoxy oligomer with(s) glycidoxyalkyl group(s) (methoxy / ethoxysilyl resin with(s) glycidoxyalkyl group(s), X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.; SiO2 content = 39 wt%, viscosity (25°C) = 12mm 2 / s, average molecular weight = 3863) was added dropwise to the curing agent under stirring over a period of 3 minutes. Then, the resulting curing agent was fully mixed for 5 minutes to obtain coated particles A. Manufacturing example 2

[0131] Except that the amount of alkoxy oligomer having(s) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.) was changed from 200 g to 50 g, coated particles B were prepared in the same manner as in Preparation Example 1. Manufacturing example 3

[0132] Except that the amount of alkoxy oligomer having(s) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.) was changed from 200 g to 10 g, the coated particles C were prepared in the same manner as in Preparation Example 1. Manufacturing example 4

[0133] Except that the amount of alkoxy oligomer having(s) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.) was changed from 200 g to 5 g, the coated particles D were prepared in the same manner as in Preparation Example 1. Manufacturing example 5

[0134] Except that instead of 200g of alkoxy oligomer with(s) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.), 50g of alkoxy oligomer with(s) mercaptoalkyl group(s) (methoxy / ethoxysilyl resin with mercaptoalkyl group, X-41-1805, manufactured by Shin-Etsu Chemical Co., Ltd.; SiO2 content = 43 wt%; viscosity (25°C) = 30mm 2 / s, average molecular weight = 7059), the coated particles E were prepared in the same manner as in Preparation Example 1. Manufacturing example 6

[0135] Except that instead of 200g of alkoxy oligomer having(a) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.), 50g of alkoxy oligomer having(a) aminoalkyl group(s) (methoxysilyl resin having(a) 3-aminopropyl group(s), X-40-2651, manufactured by Shin-Etsu Chemical Co., Ltd.; SiO2 content = 75 wt%, viscosity (25°C) = 20 mm 2 / s, average molecular weight = 3917), the coated particles F were prepared in the same manner as in Preparation Example 1. Production example 7 (comparative example)

[0136] Except that instead of 200g of alkoxy oligomer having(a) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.), 50g of silane coupling agent having(a) glycidoxyalkyl group(s) (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.; viscosity (25°C) = 3 mm 2 / s) was used, the coated particles G were prepared in the same way as in Preparation Example 1. Manufacturing example 8

[0137] Except that instead of the imidazole adduct-based latent curing agent (PN-50J, manufactured by Ajinomoto Fine Techno Co., Inc.), a tertiary amine adduct-based latent curing agent (MY-24J, manufactured by Ajinomoto Fine Techno Co., Inc.; average particle diameter = 2.5 µm, density = 1.2 g / cm 3 ; specific surface area = 2.0m 2 / g; d90 / d50 = 1.9), the coated particles H were prepared in the same manner as in Preparation Example 2. Manufacturing example 9

[0138] Except that instead of the imidazole adduct-based latent curing agent (PN-50J, manufactured by Ajinomoto Fine Techno Co., Inc.), a tertiary amine adduct-based latent curing agent (FXR-1081, manufactured by T&K TOKA Corporation; average particle diameter = 4.0 µm; density = 1.1 g / cm 3 ; specific surface area = 1.4 m 2 / g; d90 / d50 = 1.9), the coated particles I were prepared in the same manner as in Preparation Example 2. Measurement of particle size

[0139] The mean particle size of the particles was measured using a laser diffraction particle size distribution meter (SALD-2200, manufactured by Shimadzu Corporation). Polyoxyethylene(20)sorbitan monolaurate solution was used as the dispersion medium. The results are shown in Table 1. Measurement of the amount of alkoxy oligomer

[0140] The coated particles were thoroughly washed with hexane and then dried under reduced pressure to obtain washed coated particles. 500 mg of the washed coated particles were heated in an electric furnace at a temperature of 660°C for 2 hours. The mass of alkoxy oligomer contained in the washed coated particles was obtained by dividing the mass of SiO2 obtained as ash by the SiO2 content in the alkoxy oligomer, and then the amount of alkoxy oligomer (in wt%) was calculated with respect to 100 wt% of uncoated epoxy resin curing agent particles. Calculation of the amount of alkoxy oligomer per unit surface area

[0141] As above, the mass of alkoxy oligomer in the washed coated particles was determined. Then, the amount of alkoxy oligomer in the coated particles per unit surface area of the epoxy resin curing agent particles was calculated by dividing the obtained mass of alkoxy oligomer by the total surface area of the uncoated epoxy resin curing agent particles ((weight of curing agent particles) x (specific surface area of the curing agent particles)). Mass of SiO2 in the coated particles (wt%)

[0142] The SiO2 content (wt%) relative to 100 wt% of the coated particles was calculated from the mass of SiO2 obtained as ash as above. < Assessment >Acid anhydride resistance (measurement of viscosity increase rate)

[0143] To 100 parts by weight of epoxy resin (jER828EL, manufactured by Mitsubishi Chemical Corporation, epoxy equivalent = 190) and 80 parts by weight of acid anhydride curing agent (HN-2200, manufactured by Hitachi Chemical Co., Ltd.) were added 3 parts by weight of coated particles A to F, H or I (Working Examples 1 to 8), the coated particles G (Comparative Example 1), an uncoated imidazole adduct-based latent curing agent (PN-50J, manufactured by Ajinomoto Fine Techno Co., Inc.) (Comparative Example 2)) or an uncoated tertiary amine adduct-based latent curing agent (MY-24J, manufactured by Ajinomoto Fine Techno Co., Inc.) (Comparative Example 3) or FXR-1081, manufactured by T&K TOKA Corporation (Comparative Example 4), then mixed by a planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition.Then, 0.15 parts by weight of an alkoxy oligomer having a glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.) was added to the resin composition of Comparative Example 2 (Comparative Example 5), followed by stirring with a planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. The thus-obtained resin compositions were allowed to stand for 3 days at a temperature of 40°C, then the viscosities of the resins were measured, and the viscosity increase rates were determined according to the formula below.

[0144] Viscosities were determined using an RE80 type viscosimeter (cone rotor: 1.34°×R24, manufactured by Toki Sangyo Co., Ltd.). Viscosities are measured by adding 1.0 to 1.5 ml of a target resin composition after rotation for 120 seconds at a rotor speed of 20 rpm (unit = Pa s). ((Viscosity after 3 days at 40°C) / (Initial viscosity immediately after stirring)−1)×100=Viscosity increase rate[%]

[0145] The lower the viscosity increase rate, the better the acid anhydride resistance. The results were evaluated as follows: 30% or less = excellent (⊚); higher than 30%, but not more than 40% = good (○), higher than 40%, but not more than 50% = satisfactory (Δ), higher than 50% = bad (×). The results are presented in Table 1. Solvent resistance (measurement of viscosity increase rate)

[0146] To 100 parts by weight of epoxy resin (jER828EL, manufactured by Mitsubishi Chemical Corporation, epoxy equivalent = 190) and 10 parts by weight of solvent (methyl ethyl ketone) were added 20 parts by weight of coated particles A to F, H or I (Working Examples 1 to 8), the coated particles G (Comparative Example 1), an uncoated imidazole adduct-based latent curing agent (PN-50J, manufactured by Ajinomoto Fine Techno Co., Inc.) (Comparative Example 2)) or an uncoated tertiary amine adduct-based latent curing agent (MY-24J, manufactured by Ajinomoto Fine Techno Co., Inc.) (Comparative Example 3) or FXR-1081, manufactured by T&K TOKA Corporation (Comparative Example 4), then by means of a planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. Then, 1 wt.-part of alkoxy oligomer having(s) glycidoxyalkyl group(s) (X-41-1053, manufactured by Shin-Etsu Chemical Co., Ltd.) (Comparative Example 5), followed by stirring with a planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. The thus-obtained resin compositions were allowed to stand for 1 week at a temperature of 25°C, then the viscosities of the resins were measured, and the viscosity increase rates were determined according to the formula below.

[0147] Viscosities were determined using an RE80 type viscosimeter (cone rotor: 1.34°×R24, manufactured by Toki Sangyo Co., Ltd.). Viscosities are measured by adding 1.0 to 1.5 ml of a target resin composition after rotation for 120 seconds at a rotor speed of 20 rpm (unit = Pa s). ((Viscosity after 1 week at 25°C) / (Initial viscosity immediately after stirring)−1)×100=Viscosity increase rate[%]

[0148] The lower the viscosity thickening rate, the better the solvent resistance. The results were evaluated as follows: 25% or less = excellent (⊚), higher than 25%, but not more than 50% = good (○), higher than 50%, but not more than 100% = satisfactory (Δ), higher than 100% = bad (×). The results are presented in Table 1. [Table 1] average particle diameter Average particle diameter ratio of coated particles to (A) epoxy resin hardener particles (fold) Mass of (B) alkoxy oligomer relative to the mass of (A) epoxy resin curing agent particles (wt%) Amount of alkoxy oligomer per unit surface area (mg / m 2 ) SiO2 content in coated particles (wt%) Acid anhydride resistance (viscosity increase rate %) Solvent resistance (viscosity increase rate %) Example 1 Coated particles A 7 µm 2,8 20 % 103,0 6,5 % ⊚ ⊚ Example 2 Coated particles B 4,5 µm 1,8 5% 28,0 1,9% ⊚ ⊚ Example 3 Coated particles C 3,0 µm 1,2 1% 5,0 0,4 % ○ Δ Example 4 Coated particles D 3,0 µm 1,2 0,50 % 3,0 0,2 % Δ Δ Example 5 Coated particles E 4,5 µm 1,8 5% 23,0 2,0 % ○ ⊚ Example 6 Coated particles F 5,0 µm 2,0 5% 24,0 3,5 % Δ Δ Example 7 Coated particles H 5,0 µm 2,0 5% 25,0 1,9% ⊚ ○ Example 8 Coated particles I 8,0 µm 2,0 5% 35,7 1,9% ○ Δ Comparison example 1 Coated particles G 13 µm 5,2 - - 1,4% × Δ Comparison example 2 PN-50J 2,5 µm - - - - × × Comparison example 3 MY-24J 2,5 µm - - - - × Δ Comparison example 4 FXR-1081 4,0 µm - - - - × × Comparison example 5 PN-50J + X-41-1053 2,5 µm - 5% - - × × Production of adhesives

[0149] To 100 parts by weight of an epoxy resin (jER828EL, manufactured by Mitsubiche Chemical Corporation), 69 parts by weight of trimethylolpropane tris(3-mercaptopropionate) (TMTP, manufactured by Yodo kagaku Co., Ltd., thiol equivalent = 133), and 100 parts by weight of silica (SC5500-SXJ, manufactured by Admatechs company Limited) were added 10 parts by weight of the coated particles A (Preparation Example 1), followed by stirring with the planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. In accordance with JIS-K6850, an adhesive test sample of the obtained resin composition was formed using a polished mild steel sheet (JISG3141, SPCC, Polished with #120) and cured at 100°C for 30 minutes. The tensile lap-shear bond strength of the sample was measured using a Universal Testing Machine (AC-50KN-CM, manufactured by Toyo Baldwin Co., Ltd.).) according to JIS-K6850, and to 23N / mm. 2 This confirmed that the prepared resin composition was suitable as an adhesive. Production of underfill material

[0150] Two parts by weight of the coated particles A were added to an epoxy resin containing 10 parts by weight of jER807 (manufactured by Mitsubishi Chemical Corporation, epoxy equivalent = 170) and 5.3 parts by weight of EX-216L (manufactured by Nagase ChemteX Corporation, epoxy equivalent = 135), 27.5 parts by weight of acid anhydride (HN-2200, manufactured by Hitachi Chemical Co., Ltd.), 50 parts by weight of silica (SC5500-SXJ, manufactured by Admatechs Company Limited, spherical quartz glass powder), and 0.5 part by weight of silane coupling agent (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.), followed by stirring with the planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. The viscosity of the resulting resin composition was measured using an RE80 type viscometer (cone rotor: 1.34°×R24, manufactured by Toki Sangyo Co., Ltd.) and found to be 1000 mPa s (rotor speed = 20 rpm).Based on the value at a rotor rotation of 2 rpm, the thixotropy ratio was also determined to be 1.1, which confirmed that the resin composition is suitable as an underfill material. Production of electrically conductive material

[0151] 25 parts by weight of the coated particles A (Preparation Example 1) were added to an epoxy resin containing 15 parts by weight of ZX-1059 (manufactured by NIPPON STEEL & SUMIKIN CHEMICAL Co., Ltd., epoxy equivalent = 165), 30 parts by weight of YDF-8170 (bisphenol A type epoxy resin, manufactured by NIPPON STEEL & SUMIKIN CHEMICAL Co., Ltd., epoxy equivalent = 160), 10 parts by weight of ZX-1542 (trimethylolpropane triglycidyl ether, manufactured by NIPPON STEEL & SUMIKIN CHEMICAL Co., Ltd., epoxy equivalent = 122), 10 parts by weight of X-22-163 (siloxane glycidyl ether, manufactured by Shin-Etsu Chemical Co., Ltd., epoxy equivalent = 200), 30 parts by weight of RKB-3040 (manufactured by Resinous Kasei Co., Ltd., epoxy resin with core-shell polymer, bisphenol A type and bisphenol F type resin 71 wt%, epoxy equivalent = 230), 15 parts by weight of core-shell polymer (JF-003, manufactured by Mitsubishi Rayon Co., Ltd., acrylic rubber particles), 1.5 parts by weight-Proportions of silane coupling agent (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.) and silver particles (EA0101, manufactured by Metalor Technologies International SA), followed by stirring with a planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. The resulting resin composition was applied to an FR-4 board to form a doctor blade coating with a width of 2 mm, a thickness of 80 µm, and a length of 12 mm, and then cured in a forced-air oven (DF-610, manufactured by Yamato Scientific Co., Ltd.) at a temperature of 130°C for 60 minutes to form a test sample for measuring electrical resistivity.Using a digital multimeter (R6552, manufactured by ADVANTEST Corporation), the resistance value of the obtained resin composition was measured in a 4-pole mode at a distance of 100 mm, and then the specific electrical resistance was calculated to be 0.5 x 10. -3 Ω cm was calculated. Furthermore, in accordance with JIS-K6850, a test adhesion sample of the resin composition was prepared using a copper-plated laminate plate measuring 100 mm x 25 mm x 0.8 mm, which was coated with gold plating, and cured at 130°C for 60 minutes. The tensile lap-shear bond strength of the sample was measured using a Universal Testing Machine (AC-50KN-CM, manufactured by Toyo Baldwin Co., Ltd.) according to JIS-K6850 and found to be 3.1 N / mm 2 Thus, it was confirmed that the resin composition produced is suitable as an electrically conductive material. Preparation of a resin composition for composite material

[0152] Three parts by weight of the coated particles A were added to 80 parts by weight of jER828EL, 20 parts by weight of MX-125 (manufactured by Kaneka Corporation, 75% by weight of bisphenol A-type epoxy resin, 25% by weight of core-shell polymer, core copolymer: styrene and butadiene, epoxy equivalent 250), and 80 parts by weight of acid anhydride (HN-2200, manufactured by Hitachi Chemical Co., Ltd.), followed by stirring with a planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition. The obtained resin composition was cured in a hot air circulating oven at a temperature of 130°C for 60 minutes to obtain a resin sheet with a thickness of 6 mm. A sample for the SENB test according to ASTMD5045-99 was prepared from the obtained resin plate and used as a test sample for measuring fracture toughness.The fracture toughness of the sample was measured using a Universal Testing Machine (AC-50KN-CM, manufactured by Toyo Baldwin Co., Ltd.) according to ASTMD5045-99 and found to be 1.2MPa / m. 1 / 2 Thus, it was confirmed that the prepared resin composition was suitable as a resin composition for a composite material. Production of thermally conductive material

[0153] 10 parts by weight of coated particles A (Preparation Example 1) were added to 100 parts by weight of epoxy resin (jER828EL, manufactured by Mitsubishi Chemical Corporation), 69 parts by weight of trimethylolpropane tris(3-mercaptopropionate) (TMTP, manufactured by Yodo Kagaku Co., Ltd.), 5 parts by weight of silane coupling agent (KBM-403, manufactured by Shin-Etsu Chemical Co., Ltd.), and alumina containing 290 parts by weight of DAW-45 (manufactured by Denka Company Limited, D50 = 43.3 µm), 290 parts by weight of DAW-05 (manufactured by Denka Company Limited, D50 = 5.1 µm), and 150 parts by weight of ASFP-20 (manufactured by Denka Company Limited, D50 = 0.3 µm), followed by by stirring with the planetary centrifugal mixer (THINKY MIXER ARV-310, manufactured by THINKY Corporation) to obtain a resin composition.The obtained resin composition was cured at 100°C for 30 minutes to form a columnar cured body with a diameter of 30 mm and a thickness of 5 mm, which served as a test sample for thermal conductivity measurement. Then, the thermal conductivity was measured according to the method of IS022007-2 using a hot disk thermal constant analyzer (TPS2500, manufactured by Kyoto Electronics Manufacturing Co., Ltd.) and found to be 1.5 W / mK. Thus, it was confirmed that the prepared resin composition was usable as a thermally conductive material. [Industrial applicability]

[0154] The coated particles used in the present invention can be advantageously used as curing agents or curing accelerators for epoxy resins, such as FRP matrix resins. Epoxy resin compositions containing the coated particles and epoxy resins can be used as epoxy resin materials for fields such as construction, civil engineering, automobiles, ships, aerospace, mechanical engineering, robotics, telecommunications, electrical and electronics industries, semiconductors, monitors, etc., and can be used as an adhesive, binder, electrically conductive materials, magnetic materials, thermally conductive materials, insulating materials, sealing materials, coating materials, paints, and the like.

Claims

[1] Epoxy resin composition containing: coated particles comprising: (A) Hardener particles for epoxy resin and (B) Alkoxy oligomer, wherein the surfaces of the curing agent particles for epoxy resin are coated with the alkoxy oligomer; and an epoxy resin. [2] The epoxy resin composition according to claim 1, wherein the (A) curing agent particles for epoxy resin are a latent curing agent. [3] The epoxy resin composition according to claim 1 or 2, wherein the (A) curing agent particles for epoxy resin are at least one compound selected from the group consisting of amine-based latent curing agents, urea compounds, dicyandiamide, and hydrazide compounds. [4] The epoxy resin composition according to claim 3, wherein (A) the curing agent particles for epoxy resin are at least one amine-based latent curing agent selected from the group consisting of a tertiary amine adduct-based latent curing agent and an imidazole adduct-based latent curing agent. [5] The epoxy resin composition according to any one of claims 1 to 4, wherein the average particle diameter D of the coated particles is not less than 1.0 times to not more than 5.0 times the average particle diameter of the (A) curing agent particles for epoxy resin. [6] The epoxy resin composition according to any one of claims 1 to 5, wherein the average particle diameter D of the coated particles is 2.5µm ≦ D ≦ 12.5µm. [7] The epoxy resin composition according to any one of claims 1 to 6, wherein the amount of the (B) alkoxy oligomer is 0.1 to 40 wt% based on the (A) curing agent particles for epoxy resin as 100 wt%. [8] The epoxy resin composition according to any one of claims 1 to 7, wherein the amount of the (B) alkoxy oligomer per unit surface area of the (A) curing agent particles for epoxy resin is 0.5 mg / m 2 or more. [9] The epoxy resin composition according to any one of claims 1 to 8, wherein the SiO2 content in the coated particles is 0.04 to 11 wt% based on the coated particles as 100 wt%. [10] Epoxy resin composition according to any one of claims 1 to 9, wherein the (B) alkoxy oligomer has a viscosity (25°C) of 10 mm 2 / s up to 200mm 2 / s. [11] The epoxy resin composition according to any one of claims 1 to 10, wherein the (B) alkoxy oligomer is at least one compound selected from the group consisting of alkoxysilyl resins having glycidoxyalkyl group(s), alkoxysilyl resins having aminoalkyl group(s), and alkoxysilyl resins having mercaptoalkyl group(s). [12] The epoxy resin composition according to claim 11, wherein the (B) alkoxy oligomer is at least one compound selected from the group consisting of alkoxysilyl resins having(s) glycidoxypropyl group(s), alkoxysilyl resins having(s) aminopropyl group(s), alkoxysilyl resins having(s) N-2-(aminoethyl)-3-aminopropyl group(s), alkoxysilyl resins having(s) N-phenyl-3-aminopropyl group(s), and alkoxysilyl resins having(s) mercaptopropyl group(s). [13] The epoxy resin composition according to claim 12, wherein the (B) alkoxy oligomer is at least one compound selected from the group consisting of methoxysilyl resins having glycidoxypropyl group(s), methoxysilyl resins having aminopropyl group(s), ethoxysilyl resins having aminopropyl group(s), methoxysilyl resins having N-2-(aminoethyl)-3-aminopropyl group(s), methoxysilyl resins having N-phenyl-3-aminopropyl group(s), and methoxysilyl resins having mercaptopropyl group(s). [14] The epoxy resin composition according to any one of claims 1 to 10, wherein the (B) alkoxy oligomer is represented by the following general formula (1): R1, R2 and R3 are each independently a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, X is a lower alkyl group, glycidoxyalkyl group, aminoalkyl group or mercaptoalkyl group, n is an integer from 2 to 10, the multiple X's can be the same or different from each other, the multiple R3s present can be the same or different from each other, and at least one of the multiple Xs is a glycidoxyalkyl group, aminoalkyl group or mercaptoalkyl group. [15] The epoxy resin composition according to any one of claims 1 to 14, which further contains at least one component selected from the group consisting of curing agents, curing accelerators, thermosetting resins, thermoplastic resin, inorganic fillers, organic fillers, thickeners, defoamers, leveling agents, coupling agents, colorants and organic solvents. [16] The epoxy resin composition according to any one of claims 1 to 15, which contains an inorganic filler, wherein the inorganic filler is at least one selected from the group consisting of silica, electrically conductive fillers, magnetic fillers and thermally conductive fillers. [17] Epoxy resin composition according to any one of claims 1 to 16, which is a liquid, pasty or film-like composition. [18] The epoxy resin composition according to any one of claims 1 to 17, which is an adhesive, binder, electrically conductive material, magnetic material, thermally conductive material, insulating material, sealing material, coating material or a paint. [19] A sheet or layer material or composite material containing the epoxy resin composition according to any one of claims 1 to 18.