JP2014065782A - Curing agent for epoxy resin, and curable epoxy resin composition containing the curing agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a curing agent for epoxy resin that exhibits a fast-curing property which cures in a short period of time at a high temperature and a high fluidity when blended with epoxy resin.SOLUTION: The curing agent for epoxy resin according to the present invention contains a reaction product between (A) a compound having at least one epoxy group and (B) a compound having at least one tertiary amino group and at least one active hydrogen group, as its main component and the molecular weight distribution (weight average molecular weight/number average molecular weight) of the reaction product is more than 1 and less than or equal to 1.5.

Description

  The present invention relates to a curing agent for epoxy resin, a method for producing the same, and a curable epoxy resin composition containing the curing agent.

  Epoxy resins have excellent performance in terms of mechanical properties, electrical properties, thermal properties, chemical resistance, adhesiveness, etc., so that paints, insulating materials for electrical and electronic materials, adhesives, etc. It is used for a wide range of applications.

  In recent years, there has been an increasing demand for curable compositions having highly controlled properties, particularly in the field of electronic materials. Highly controlled properties include, for example, long-term potential at room temperature or lower and properties that cure in a short time at a high temperature such as 80 ° C. or higher (hereinafter also referred to as “fast curing”). In addition, the curable composition is strongly required to have, for example, a property capable of suppressing the generation of aggregated foreign matter during the blending operation of the epoxy resin and the curing agent, and a high fluidity capable of easily removing the aggregated foreign matter. ing.

  As a curing agent for an epoxy resin that imparts fast curability, Patent Document 1 discloses a curing agent that uses a reaction product of monomethylamine and polyglycidyl ether. Further, as a curing agent for an epoxy resin that imparts high fluidity, Patent Document 2 discloses that a molecular weight distribution (weight average molecular weight / number average molecular weight) is more than 1 and 7 or less, an epoxy group-containing compound and an amine. A microcapsule-type curing agent containing an amino group-containing compound obtained by reaction with a compound and a low-molecular amine compound as a main component and containing a specific amount of moisture is disclosed.

Japanese Patent Laid-Open No. 9-316175 International Publication No. 2007-037378

  However, since the epoxy resin composition using the epoxy resin curing agent described in Patent Document 1 cures very rapidly even at room temperature such as 25 ° C., fluidity decreases as the curing proceeds. Cheap. Therefore, it cannot be said that the epoxy resin composition sufficiently satisfies the properties required in recent years. Moreover, the epoxy resin composition using the microcapsule type epoxy resin curing agent described in Patent Document 2 also has further improvements in curability and fluidity, and has more excellent fast curability and high fluidity. It is demanded.

  In view of the above circumstances, the problem to be solved by the present invention is a fast curing property that cures in a short time at high temperature, and a curing agent for epoxy resin that can impart high fluidity when blended with an epoxy resin, and a method for producing the same. Another object is to provide a curable epoxy resin composition containing the epoxy resin curing agent and an epoxy resin.

  As a result of intensive studies to achieve the above object, the inventors of the present invention include a specific reaction product as a main component, and the molecular weight distribution (weight average molecular weight / number average molecular weight) of the reaction product is defined as a specific range. By using the cured epoxy resin curing agent, it has been found that an epoxy resin composition having excellent fast curability and excellent fluidity can be provided, and the present invention has been completed. That is, the present invention is as follows.

[1]
(A) a compound having at least one epoxy group;
(B) a reaction product of a compound having at least one tertiary amino group and at least one active hydrogen group as a main component,
A curing agent for epoxy resin, wherein the molecular weight distribution (weight average molecular weight / number average molecular weight) of the reaction product is more than 1 and 1.5 or less.

[2]
The curing agent for epoxy resin according to [1], wherein the molecular weight distribution (weight average molecular weight / number average molecular weight) of the reaction product is more than 1 and 1.2 or less.

[3]
The curing agent for epoxy resin according to [1] or [2], wherein the reaction product has a weight average molecular weight of 200 or more and 8000 or less.

[4]
The curing agent for epoxy resin according to any one of [1] to [3], wherein the compound (B) having at least one tertiary amino group and at least one active hydrogen group is an imidazole or an imidazoline.

[5]
It is a manufacturing method of the hardening | curing agent for epoxy resins in any one of [1]-[4],
(A) For one equivalent of an epoxy group of a compound having at least one epoxy group, at least one equivalent of a compound having at least one tertiary amino group and at least one active hydrogen group is reacted in terms of active hydrogen to produce a reaction. Obtaining a product;
(B) purifying the obtained reaction product;
The manufacturing method of the hardening | curing agent for epoxy resins containing.

[6]
A curable epoxy resin composition comprising the epoxy resin curing agent according to any one of [1] to [4] and an epoxy resin.

[7]
An epoxy cured product obtained by curing the curable epoxy resin composition according to [6].

[8]
The manufacturing method of an epoxy hardened body including the process of hardening the curable epoxy resin composition as described in [6].

  According to the present invention, a curing agent for an epoxy resin capable of imparting a high curability when blended with an epoxy resin, a rapid curing property that cures in a short time at a high temperature, a method for producing the same, and a curing agent for the epoxy resin A curable epoxy resin composition containing an epoxy resin can be provided.

  Hereinafter, a mode for carrying out the present invention (hereinafter referred to as the present embodiment) will be described in detail. In addition, this invention is not limited to the following embodiment, It can implement by changing variously within the range of the summary.

[Curing agent for epoxy resin]
The curing agent for epoxy resin of the present embodiment is
(A) a compound having at least one epoxy group;
(B) a reaction product of a compound having at least one tertiary amino group and at least one active hydrogen group as a main component,
The molecular weight distribution (weight average molecular weight / number average molecular weight) of the reaction product is more than 1 and 1.5 or less.

  In the present embodiment, the main component is preferably a component having a proportion of 50% by mass or more, more preferably 80% by mass or more, in the epoxy resin curing agent. In the epoxy resin curing agent of the present embodiment, the content of the reaction product may be 100% by mass.

  (A) Although it does not specifically limit as a compound which has at least 1 epoxy group, For example, any of a monoepoxy compound and a polyhydric epoxy compound, those mixtures, etc. are mentioned.

  The monoepoxy compound is not particularly limited. Examples include acetate, glycidyl butyrate, glycidyl hexoate, and glycidyl benzoate.

  Although it does not specifically limit as a polyhydric epoxy compound, For example, bisphenol A, bisphenol F, bisphenol AD, bisphenol S, tetramethyl bisphenol A, tetramethyl bisphenol F, tetramethyl bisphenol AD, tetramethyl bisphenol S, tetrabromo bisphenol A Bisphenol type epoxy resin obtained by glycidylation of bisphenols such as tetrachlorobisphenol A and tetrafluorobisphenol A; glycidyl other dihydric phenols such as biphenol, dihydroxynaphthalene and 9,9-bis (4-hydroxyphenyl) fluorene 1,1,1-tris (4-hydroxyphenyl) methane, 4,4- (1- (4- (1- (4-hydroxyphenyl) -1- Epoxy resin obtained by glycidylation of trisphenols such as tilethyl) phenyl) ethylidene) bisphenol; epoxy resin obtained by glycidylation of tetrakisphenols such as 1,1,2,2, -tetrakis (4-hydroxyphenyl) ethane; phenol novolac , Cresol novolaks, bisphenol A novolaks, brominated phenol novolaks, novolac epoxy resins obtained by glycidylation of novolaks such as brominated bisphenol A novolacs, etc .; epoxy resins obtained by glycidylation of polyhydric phenols, glycerin and polyethylene glycol Aliphatic ether type epoxy resin obtained by glycidylation of monohydric alcohol; ether ester type epoxy resin obtained by glycidylation of hydroxycarboxylic acid such as p-oxybenzoic acid and β-oxynaphthoic acid Xy resin; ester type epoxy resin obtained by glycidylation of polycarboxylic acid such as phthalic acid or terephthalic acid; amine type such as glycidated product of amine compounds such as 4,4-diaminodiphenylmethane and m-aminophenol, and triglycidyl isocyanurate Examples thereof include glycidyl type epoxy resins such as epoxy resins and alicyclic epoxides such as 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate.

  (A) The compound having at least one epoxy group is preferably a polyvalent epoxy compound from the viewpoint of enhancing the storage stability of the curable epoxy resin composition. As the polyvalent epoxy compound, a glycidyl type epoxy resin is preferable from the viewpoint of overwhelmingly increasing the productivity of amine adducts, and an epoxy obtained by glycidylating polyhydric phenols from the viewpoint of improving the adhesiveness and heat resistance of the cured product. A resin is more preferable, and a bisphenol type epoxy resin is more preferable. Among them, an epoxy resin obtained by glycidylating bisphenol A and an epoxy resin obtained by glycidylating bisphenol F are more preferable, and an epoxy resin obtained by glycidylating bisphenol A is further more preferable.

  These components (A) may be used alone or in combination of two or more.

  (B) In the compound having at least one tertiary amino group and at least one active hydrogen group, the active hydrogen group is not particularly limited, and examples thereof include a primary amino group, a secondary amino group, a hydroxyl group, a thiol group, and a carboxyl group. Examples include acid and hydrazide groups.

  (B) The compound having at least one tertiary amino group and at least one active hydrogen group is not particularly limited, and examples thereof include 2-dimethylaminoethanol, 1-methyl-2-dimethylaminoethanol, 1-phenoxymethyl. Amino alcohols such as 2-dimethylaminoethanol, 2-diethylaminoethanol, 1-butoxymethyl-2-dimethylaminoethanol, methyldiethanolamine, triethanolamine, N-β-hydroxyethylmorpholine; 2- (dimethylaminomethyl) Aminophenols such as phenol and 2,4,6-tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 2-phenyl Nilimidazole, 1-aminoethyl-2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-phenoxypropyl) -2-ethyl-4- Imidazoles such as methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazole, 1- (2-hydroxy-3-butoxypropyl) -2-ethyl-4-methylimidazole; 2-hydroxy-3-phenoxypropyl) -2-phenylimidazoline, 1- (2-hydroxy-3-butoxypropyl) -2-methylimidazoline, 2-methylimidazoline, 2,4-dimethylimidazoline, 2-ethylimidazoline, 2-ethyl-4-methylimidazoline, 2-benzylimidazoli , 2-phenylimidazoline, 2- (o-tolyl) -imidazoline, tetramethylene-bis-imidazoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-imidazoline, 1,3,3-trimethyl -1,4-tetramethylene-bis-imidazoline, 1,1,3-trimethyl-1,4-tetramethylene-bis-4-methylimidazoline, 1,3,3-trimethyl-1,4-tetramethylene-bis Such as -4-methylimidazoline, 1,2-phenylene-bis-imidazoline, 1,3-phenylene-bis-imidazoline, 1,4-phenylene-bis-imidazoline, 1,4-phenylene-bis-4-methylimidazoline, etc. Imidazolines; dimethylaminopropylamine, diethylaminopropylamine, dipropylaminopropylamine , Tertiary aminoamines such as dibutylaminopropylamine, dimethylaminoethylamine, diethylaminoethylamine, dipropylaminoethylamine, dibutylaminoethylamine, N-methylpiperazine, N-aminoethylpiperazine, diethylaminoethylpiperazine; 2-dimethylaminoethane Amino mercaptans such as thiol, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptopyridine, 4-mercaptopyridine; N, N-dimethylaminobenzoic acid, N, N-dimethylglycine, nicotinic acid, isonicotine Aminocarboxylic acids such as acid and picolinic acid; aminohydrazides such as N, N-dimethylglycine hydrazide, nicotinic acid hydrazide and isonicotinic acid hydrazide;

  In the present embodiment, (B) the compound having at least one tertiary amino group and at least one active hydrogen group is preferably an imidazole or imidazoline, such as 2-methylimidazole or 2-ethyl-4-methyl. Imidazole is more preferred.

  The curing agent for epoxy resin of the present embodiment is particularly preferably a curing agent containing as a main component a reaction product obtained by a reaction between an epoxy resin and imidazoles or imidazolines.

(Molecular weight distribution of reaction products)
In the present embodiment, the molecular weight distribution of the reaction product of (A) a compound having at least one epoxy group and (B) a compound having at least one tertiary amino group and at least one active hydrogen group is It is defined as the ratio of the weight average molecular weight to the number average molecular weight (weight average molecular weight / number average molecular weight), and is calculated from the molecular weight determined in terms of polystyrene using gel permeation chromatography (hereinafter also referred to as “GPC”). In the present embodiment, the molecular weight distribution of the reaction product is more than 1 and 1.5 or less, and preferably more than 1 and 1.2 or less. By controlling the molecular weight distribution of the reaction product within the above range, it is possible to provide an epoxy resin curing agent that is not only excellent in fast curability but also extremely fluid when mixed with an epoxy resin. . The reason for this effect is not clear, but by narrowing the molecular weight distribution of the reaction product within the above range, the epoxy resin curing agent is uniformly dissolved and dispersed in the epoxy resin. It is presumed that this is due to the fact that the easy curing reaction proceeds.

  As a method for controlling the molecular weight distribution of the reaction product within the above range, for example, (A) one equivalent of an epoxy group of a compound having at least one epoxy group, (B) at least one tertiary amino group And a method of controlling the molecular weight distribution of the reaction product by purifying a reaction product obtained by reacting a compound having at least one active hydrogen group with 2 equivalents or more in terms of active hydrogen.

(Molecular weight of reaction product)
In this embodiment, the weight average molecular weight of the reaction product of (A) a compound having at least one epoxy group and (B) a compound having at least one tertiary amino group and at least one active hydrogen group is 200 to 8000 is preferable. The lower limit of the weight average molecular weight of the reaction product is preferably 200 or more, more preferably 300 or more, and still more preferably 400 or more. When the lower limit of the weight average molecular weight of the reaction product is within the above range, the hygroscopicity of the curable epoxy resin composition tends to be low, and bubbles due to moisture tend not to be mixed into the cured product. Moreover, the upper limit of the weight average molecular weight of the reaction product is preferably 8000 or less, more preferably 6000 or less, and further preferably 5000 or less, from the viewpoint of fast curability.

  In this Embodiment, the weight average molecular weight of the said reaction product can be calculated | required by polystyrene conversion using GPC method.

  As a method for controlling the weight average molecular weight of the reaction product within the above range, for example, (A) one equivalent of an epoxy group of a compound having at least one epoxy group, (B) at least one tertiary amino A method of controlling the weight average molecular weight of the reaction product by purifying a reaction product obtained by reacting 2 equivalents or more of a group and a compound having at least one active hydrogen group in terms of active hydrogen.

(Other ingredients)
The curing agent for epoxy resin of the present embodiment may further contain other components. The other components are not particularly limited. For example, (a) in the above-described (B) method for producing a compound having at least one tertiary amino group and at least one active hydrogen group, or a curing agent for epoxy resin described later. And the solvent etc. which are used as needed in process (b) are mentioned.

[Method for producing curing agent for epoxy resin]
Next, the manufacturing method of the hardening | curing agent for epoxy resins of this Embodiment is demonstrated. Although it does not specifically limit as a manufacturing method of the hardening | curing agent for epoxy resins of this Embodiment, The manufacturing method containing two processes (a) and (b) which are demonstrated below is preferable.
(A) For one equivalent of an epoxy group of a compound having at least one epoxy group, at least one equivalent of a compound having at least one tertiary amino group and at least one active hydrogen group is reacted in terms of active hydrogen to produce a reaction. The process of obtaining things.
(B) A step of purifying the obtained reaction product.

  First, the former step (a) will be described in detail below.

  In the present embodiment, the step (a) means (A) one equivalent of an epoxy group in a compound having at least one epoxy group, and (B) at least one tertiary amino group and at least one active hydrogen. This is a step of obtaining a reaction product by reacting a compound having a group in terms of active hydrogen, preferably from 2 to 20 equivalents, more preferably from 3 to 18 equivalents. When the amount of the compound (B) having at least one tertiary amino group and at least one active hydrogen group is 2 equivalents or more, the molecular weight distribution of the resulting reaction product tends to be narrowed, which will be described later. The yield of the desired reaction product during purification in step (b) is likely to improve. From such a viewpoint, the amount of (B) used is more preferably 3 equivalents or more. Moreover, by making the usage-amount of said (B) 20 equivalent or less, the time of a removal process of an unreacted raw material becomes short, and reaction efficiency improves. From such a viewpoint, the amount of (B) used is more preferably 18 equivalents or less.

  (A) A process may be performed without a solvent and may be performed in a solvent.

  (A) Although it does not specifically limit as a solvent used as needed in a process, For example, hydrocarbons, such as benzene, toluene, xylene, a cyclohexane, a mineral spirit, a naphtha; Ketones, such as acetone, methyl ethyl ketone, methyl isobutyl ketone Esters such as ethyl acetate, acetic acid-n-butyl, propylene glycol monomethyl ether acetate; alcohols such as methanol, isopropanol, n-butanol, butyl cellosolve, butyl carbitol; dimethyl ether, diethyl ether, diphenyl ether, tetrahydrofuran, diethylene glycol dimethyl ether , Ethers such as diethylene glycol diethyl ether, dioxane and trioxane; N, N-dimethylformamide, N, N-dimethyl Acetamide, N- methyl-2-amides such as pyrrolidones; methylene chloride, chloroform, 1,1-dichloroethane, 1,2-dichloroethylene, 1-chloropropane, halogenated hydrocarbons such as chlorobenzene; water and the like. Two or more of these solvents may be used in combination. The solvent used is preferably removed by distillation or the like.

  In the step (a), the reaction temperature is preferably in the range of 25 to 250 ° C, more preferably 50 to 230 ° C, still more preferably 70 to 200 ° C. It is preferable that the reaction temperature is 25 ° C. or higher because the addition reaction rate can be increased. Further, when the reaction temperature is 250 ° C. or lower, the molecular weight distribution of the obtained reaction product tends to be narrowed, and the yield of the desired reaction product during purification in the step (b) described later is improved. Can be preferable.

  Next, details of the latter step (b) will be described.

  In the present embodiment, the step (b) means that the reaction product obtained in the step (a) is purified, so that the molecular weight distribution of the reaction product is preferably more than 1 and 1.5 or less. It is a process to do.

  The purification method of the reaction product in the step (b) is not particularly limited, and examples thereof include distillation purification, crystallization purification, and column chromatography purification.

  The distillation purification method used in the present embodiment is not particularly limited, and examples thereof include various known methods, specifically, any method such as atmospheric distillation, vacuum distillation, thin film distillation, steam distillation, and the like. . In addition, the number of stages may be simple distillation or may be performed in multiple stages using a packed tower or a holder show.

  The crystallization purification method used in the present embodiment is not particularly limited, and examples thereof include various known methods, specifically, any method such as thermal recrystallization and reprecipitation.

  The method of column chromatography purification used in the present embodiment is not particularly limited, and for example, any of various known methods, specifically, normal phase silica gel chromatography, reverse phase silica gel column chromatography, or the like. Is mentioned.

  (B) A process may be performed without a solvent and may be performed in a solvent.

  (B) As a solvent used as needed in a process, the solvent similar to the solvent used as needed in the said (a) process is mentioned. Two or more of these solvents may be used in combination.

[Curable epoxy resin composition]
Next, the curable epoxy resin composition of this Embodiment is demonstrated.

  The curable epoxy resin composition of this Embodiment contains the above-mentioned hardening | curing agent for epoxy resins, and an epoxy resin.

  The above-mentioned curing agent for epoxy resin can be suitably used as a curing agent for epoxy resin.

  In the curable epoxy resin composition of the present embodiment (hereinafter also referred to as “epoxy resin composition”), the content of the curing agent for epoxy resin described above is 0.1 to 200 with respect to 100 parts by mass of the epoxy resin. It is preferable that it is a mass part, More preferably, it is 0.5-100 mass part, More preferably, it is 1-60 mass part.

  As an epoxy resin used for the epoxy resin composition of this Embodiment, the epoxy resin which has an average of 2 or more epoxy groups per molecule is preferable. Such an epoxy resin is not particularly limited. For example, bisphenol A, bisphenol F, bisphenol AD, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol AD, tetramethylbisphenol S, tetrabromobisphenol. A, bisphenol type epoxy resin obtained by glycidylation of bisphenols such as tetrachlorobisphenol A and tetrafluorobisphenol A; other dihydric phenols such as biphenol, dihydroxynaphthalene and 9,9-bis (4-hydroxyphenyl) fluorene Glycidylated epoxy resin; 1,1,1-tris (4-hydroxyphenyl) methane, 4,4- (1- (4- (1- (4-hydroxyphenyl)- An epoxy resin obtained by glycidylating trisphenols such as methylethyl) phenyl) ethylidene) bisphenol; an epoxy resin obtained by glycidylating tetrakisphenols such as 1,1,2,2, -tetrakis (4-hydroxyphenyl) ethane; Epoxy resins obtained by glycidylating polyhydric phenols such as novolak-type epoxy resins obtained by glycidylating novolaks such as phenol novolak, cresol novolak, bisphenol A novolak, brominated phenol novolak, and brominated bisphenol A novolak; Aliphatic ether type epoxy resin obtained by glycidylation of such polyhydric alcohol; ether ether obtained by glycidylation of hydroxycarboxylic acid such as p-oxybenzoic acid and β-oxynaphthoic acid Steal type epoxy resin; ester type epoxy resin obtained by glycidylation of polycarboxylic acid such as phthalic acid and terephthalic acid; glycidylated products of amine compounds such as 4,4-diaminodiphenylmethane and m-aminophenol, triglycidyl isocyanurate, etc. Amine type epoxy resin; alicyclic epoxides such as 3,4-epoxycyclohexylmethyl-3 ′, 4′-epoxycyclohexanecarboxylate and the like.

  The said epoxy resin may be used individually by 1 type, and may be used together 2 or more types.

  The epoxy resin composition of the present embodiment can be used in combination with at least one curing agent selected from the group consisting of acid anhydrides, phenols, hydrazides, and guanidines.

  The acid anhydrides are not particularly limited. For example, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, -3-chlorophthalic anhydride, -4 -Chlorophthalic acid, benzophenone anhydride tetracarboxylic acid, succinic anhydride, methyl succinic anhydride, dimethyl succinic anhydride, dichlor succinic anhydride, methyl nadic acid, dodecyl succinic acid, chlorendec anhydride, maleic anhydride and the like.

  Although it does not specifically limit as said phenols, For example, a phenol novolak, a cresol novolak, bisphenol A novolak, bisphenol A, bisphenol F etc. are mentioned.

  The hydrazines are not particularly limited. And dihydrazide.

  The guanidines are not particularly limited, and examples thereof include dicyandiamide, methylguanidine, ethylguanidine, propylguanidine, butylguanidine, dimethylguanidine, trimethylguanidine, phenylguanidine, diphenylguanidine, and toluylguanidine.

  When using these hardening | curing agents, it is preferable that content of this hardening | curing agent is the range of 1-100 mass parts with respect to 100 mass parts of epoxy resins. When these curing agents are used in combination, in addition to obtaining excellent curing performance, a cured product having excellent heat resistance and water resistance can be obtained.

  In addition, the epoxy resin composition of the present embodiment includes, as desired, an extender, a reinforcing material, a filler, conductive fine particles, a pigment, an organic solvent, a reactive diluent, a non-reactive diluent, resins, crystallinity. Function-providing materials such as alcohol and coupling agents can be blended.

  Although it does not specifically limit as an extender, For example, inorganic substances, such as high molecular bodies, such as a thermoplastic resin and a cellulose, low molecular bodies, such as a phthalate ester, mica, etc. are mentioned.

  The reinforcing material is not particularly limited, and examples thereof include inorganic fibers such as carbon fiber, glass fiber, and asbestos fiber, and organic fibers such as aramid fiber, nylon, and polyester.

  The filler is not particularly limited. For example, coal tar, glass fiber, asbestos fiber, boron fiber, carbon fiber, cellulose, polyethylene powder, polypropylene powder, quartz powder, mineral silicate, mica, asbestos powder, Slate powder, kaolin, aluminum oxide trihydrate, aluminum hydroxide, chalk powder, gypsum, calcium carbonate, antimony trioxide, penton, silica, aerosol, lithopone, barite, titanium dioxide, carbon black, graphite, carbon nanotube, fullerene , Iron oxide, gold, silver, aluminum powder, iron powder, nano-sized metal crystals, intermetallic compounds, and the like. Any of these is effectively used according to the application.

  The conductive fine particles are not particularly limited, and examples thereof include resin particles whose surface is coated with metal particles such as gold and silver, and graphite particles.

  Although it does not specifically limit as a pigment, For example, organic pigments, such as inorganic pigments, such as a titanium dioxide, and an azo pigment etc. are mentioned.

  Although it does not specifically limit as an organic solvent, For example, toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate etc. are mentioned.

  The reactive diluent is not particularly limited. For example, butyl glycidyl ether, N, N′-glycidyl-o-toluidine, phenyl glycidyl ether, styrene oxide, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1, Examples include 6-hexanediol diglycidyl ether.

  Although it does not specifically limit as a non-reactive diluent, For example, a dioctyl phthalate, a dibutyl phthalate, a dioctyl adipate, a petroleum solvent etc. are mentioned.

  The resins are not particularly limited. For example, polyester resins, polyurethane resins, acrylic resins, polyether resins, melamine resins, urethane-modified epoxy resins, rubber-modified epoxy resins, modified epoxy resins such as alkyd-modified epoxy resins, and phenoxy resins. Etc.

  The crystalline alcohol is not particularly limited, and examples thereof include 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, pentaerythritol, sorbitol, sucrose, and trimethylolpropane.

  The coupling agent is not particularly limited, and examples thereof include silane coupling agents such as γ-glycidyloxypropyltrimethoxysilane.

  These function-imparting materials are preferably blended in the range of 0 to 90% by mass with respect to the entire epoxy resin composition, although depending on the application.

  The curable epoxy resin composition of the present embodiment is obtained by mixing a curing agent for epoxy resin, an epoxy resin, and, if necessary, other curing agents and function-imparting materials using three rolls or the like. be able to.

  The epoxy cured body of the present embodiment is obtained by curing the above curable epoxy resin composition.

  Specifically, the epoxy cured body of the present embodiment can be obtained by, for example, heating and curing the above curable epoxy resin composition. The heating method for curing the curable epoxy resin composition described above is not particularly limited. For example, a method of irradiating infrared or microwave, a method of exposing to an atmosphere heated in an oven, a heated metal, etc. Examples include a method of bringing into contact with an object.

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

  Measurement and evaluation in the following examples and comparative examples were performed as follows.

(1) Curability evaluation Mixing 100 parts by mass of bisphenol A type epoxy resin (AER250 manufactured by Asahi Kasei Chemicals, epoxy equivalent 185 g / eq) with 15 parts by mass of curing agent for epoxy resin obtained in Examples and Comparative Examples, and curing. An epoxy resin composition was prepared. The time until gelation of this curable epoxy resin composition (gelation time) was measured and evaluated as follows using a gelation tester based on JIS C-6521. That is, the gel plate is kept at 120 ° C., 0.4 mL of the curable epoxy resin composition is placed on the plate, and after the placement, the mixture is stirred with a stir bar, and the time until the yarn is not pulled, that is, until gelation is reached. Time (seconds) was measured. A gelation time of less than 50 seconds was marked with ◎, a score of 50 seconds to less than 60 seconds was marked with ○, a score of 60 seconds to less than 80 seconds was marked with Δ, and a score of 80 seconds or more was marked with ×. It was evaluated that the shorter the gelation time, the better the curability.

(2) Fluidity evaluation 10 parts by mass of epoxy resin curing agent obtained in Examples and Comparative Examples, 100 parts by mass of bisphenol A type epoxy resin, HN-2200 (Hitachi Chemical Industry Co., Ltd.) 100 parts by mass) and 500 parts by mass of silica filler having a particle size of 7 μm were kneaded with three rolls to obtain an epoxy resin composition. The epoxy resin composition was heated to 80 ° C., and then poured into a spiral flow measurement mold (80 mmφ semicircle) according to EMMI-1-66 at an injection pressure of 100 MPa, and the flow length at a curing temperature of 140 ° C. was measured. . The flow length is 230 cm or more, ◎, 200 cm or more and less than 230 cm, ◯, 150 cm or more and less than 200 cm, Δ, 100 cm or more and less than 150 cm, and x or less than 100 cm. The longer the flow length, the better the fluidity.

(3) Weight average molecular weight Using Tosoh Co., Ltd. HLC8220GPC (detector: RI), two columns: PLgel3μMIXED-E (manufactured by Polymer Laboratories), eluent: dimethylformamide 1% lithium bromide solution, calibration curve: polystyrene Gel permeation chromatography was performed under the conditions described above, and the weight average molecular weight was measured.

(4) Molecular weight distribution Using HLC8220GPC (detector: RI) manufactured by Tosoh Corporation, two columns: PLgel3μMIXED-E (manufactured by Polymer Laboratories), eluent: 1% dimethylformamide lithium bromide solution, calibration curve: polystyrene Gel permeation chromatography was performed under the conditions, and the weight average molecular weight and the number average molecular weight were measured. A value obtained by dividing the weight average molecular weight by the number average molecular weight was defined as a molecular weight distribution.

(5) Epoxy equivalent The epoxy equivalent is the mass (g) of an epoxy resin containing 1 equivalent of an epoxy group, and was determined based on JIS K-7236.

Example 1
In an eggplant flask, 10 equivalents (converted to active hydrogen) of 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in a 1/1 mixed solvent of n-butanol and toluene to obtain a solution (concentration: 50% by mass). Next, a solution (concentration) obtained by dissolving 1 equivalent (epoxy group equivalent) of a bisphenol A type epoxy resin (manufactured by Dow Chemical Co., epoxy equivalent of 175 g / equivalent) in a 1/1 mixed solvent of n-butanol and toluene. 50% by mass) was reacted at 80 ° C. while dropping the solution in the eggplant flask with a dropping funnel to obtain a reaction solution. Thereafter, 2-methylimidazole and the solvent were distilled off from the reaction solution under reduced pressure, and the residue was cooled to room temperature to obtain a solid reaction product. Components in the obtained solid reaction product are separated by reversed phase column chromatography (carrier solution; methanol: water = 2: 1 to 5: 1) using Wakogel (R) 50C18 (manufactured by Wako Pure Chemical Industries, Ltd.). By refine | purifying, the hardening | curing agent 1 for epoxy resins was obtained. The resulting epoxy resin curing agent 1 had a weight average molecular weight of 1000 and a molecular weight distribution of 1.02. The curability and fluidity were evaluated using this epoxy resin curing agent 1. The results obtained are summarized in Table 1.

(Example 2)
Curing for epoxy resin was carried out in the same manner as in Example 1, except that 8 equivalents (in terms of active hydrogen) of 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) were used for 1 equivalent of bisphenol A type epoxy resin (in terms of epoxy group). Agent 2 was obtained. The resulting epoxy resin curing agent 2 had a weight average molecular weight of 1300 and a molecular weight distribution of 1.18. The curability and fluidity were evaluated using this epoxy resin curing agent 2. The results obtained are summarized in Table 1.

(Example 3)
Curing for epoxy resin was carried out in the same manner as in Example 1, except that 5 equivalents (in terms of active hydrogen) of 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) were used for 1 equivalent of bisphenol A type epoxy resin (in terms of epoxy group). Agent 3 was obtained. The resulting epoxy resin curing agent 3 had a weight average molecular weight of 2,100 and a molecular weight distribution of 1.40. Curability and fluidity were evaluated using this epoxy resin curing agent 3. The results obtained are summarized in Table 1.

Example 4
In an eggplant flask, 5-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) 5 equivalents (in terms of active hydrogen) was dissolved in a 1/1 mixed solvent of n-butanol and toluene to obtain a solution (concentration 50% by mass). Next, a solution (concentration) obtained by adding 1/1 mixed solvent of n-butanol and toluene to 1 equivalent (epoxy group equivalent) of bisphenol F type epoxy resin (Mitsubishi Chemical Corporation, epoxy equivalent 168 g / equivalent). 50% by mass) was reacted at 80 ° C. while dropping the solution in the eggplant flask with a dropping funnel to obtain a reaction solution. Thereafter, 2-methylimidazole and the solvent were distilled off from the reaction solution under reduced pressure, and the residue was cooled to room temperature to obtain a solid reaction product. The components in the obtained solid reaction product are separated by reverse phase column chromatography (carrier solution: methanol: water = 2: 1 to 5: 1) using Wakogel (R) 50C18 (manufactured by Wako Pure Chemical Industries, Ltd.). By refine | purifying, the hardening | curing agent 4 for epoxy resins was obtained. The obtained epoxy resin curing agent 4 had a weight average molecular weight of 1700 and a molecular weight distribution of 1.36. Curability and fluidity were evaluated using this epoxy resin curing agent 4. The results obtained are summarized in Table 1.

(Example 5)
In an eggplant flask, 10 equivalents (in terms of active hydrogen) of 2-ethyl-4-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in a 1/1 mixed solvent of n-butanol and toluene (concentration 50% by mass). Got. Next, a solution (concentration) obtained by dissolving 1 equivalent (epoxy group equivalent) of bisphenol A type epoxy resin (manufactured by Dow Chemical Co., epoxy equivalent of 175 g / equivalent) in a 1/1 mixed solvent of n-butanol and toluene. 50% by mass) was reacted at 80 ° C. while dropping the solution in the eggplant flask with a dropping funnel to obtain a reaction solution. Thereafter, 2-methylimidazole and the solvent were distilled off from the reaction solution under reduced pressure, and the residue was cooled to room temperature to obtain a solid reaction product. The components in the obtained solid reaction product are separated by reverse phase column chromatography (carrier solution: methanol: water = 2: 1 to 5: 1) using Wakogel (R) 50C18 (manufactured by Wako Pure Chemical Industries, Ltd.). By refine | purifying, the hardening | curing agent 5 for epoxy resins was obtained. The resulting epoxy resin curing agent 5 had a weight average molecular weight of 1100 and a molecular weight distribution of 1.05. Curability and fluidity were evaluated using this epoxy resin curing agent 5. The results obtained are summarized in Table 1.

(Example 6)
In an eggplant flask, 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) 2 equivalents (in terms of active hydrogen) was dissolved in a 1/1 mixed solvent of n-butanol and toluene to obtain a solution (concentration 50% by mass). Next, a solution (concentration 50% by mass) obtained by dissolving 1 equivalent of phenyl glycidyl ether (manufactured by Tokyo Chemical Industry, epoxy equivalent 150 g / equivalent) in a 1/1 mixed solvent of n-butanol and toluene, A reaction solution was obtained by reacting the solution in the eggplant flask while dripping at 0 ° C. with a dropping funnel. The solvent was distilled off from the resulting reaction solution, and an extraction operation was further performed using toluene-water to remove unreacted raw material imidazole to obtain a toluene organic phase containing a reaction product. The obtained toluene organic phase was dried using magnesium sulfate, filtered, and a part of the solvent was distilled off from the filtrate. By performing thermal recrystallization using the filtrate, a curing agent 6 for epoxy resin was obtained. The resulting epoxy resin curing agent 6 had a weight average molecular weight of 600 and a molecular weight distribution of 1.17. The curability and fluidity were evaluated using this epoxy resin curing agent 6. The results obtained are summarized in Table 1.

(Example 7)
Epoxy resin in the same manner as in Example 1 except that 2.1 equivalents (in terms of active hydrogen) of 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) was used for 1 equivalent (in terms of epoxy group) of bisphenol A type epoxy resin. Curing agent 7 was obtained. The resulting epoxy resin curing agent 7 had a weight average molecular weight of 6400 and a molecular weight distribution of 1.18. Curability and fluidity were evaluated using this epoxy resin curing agent 7. The results obtained are summarized in Table 1.

(Example 8)
Curing for epoxy resin was carried out in the same manner as in Example 1 except that 8 equivalents (in terms of active hydrogen) of N-methylpiperazine (manufactured by Wako Pure Chemical Industries, Ltd.) were used for 1 equivalent (in terms of epoxy group) of bisphenol A type epoxy resin. Agent 8 was obtained. The resulting epoxy resin curing agent 8 had a weight average molecular weight of 1400 and a molecular weight distribution of 1.15. Curability and fluidity were evaluated using this epoxy resin curing agent 8. The results obtained are summarized in Table 1.

(Comparative Example 1)
In an eggplant flask, 0.7 equivalent (converted to active hydrogen) of 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd.) was dissolved in a 1/1 mixed solvent of n-butanol and toluene to obtain a solution (concentration: 50% by mass). It was. Next, a solution (concentration) obtained by dissolving 1 equivalent (epoxy group equivalent) of a bisphenol A type epoxy resin (manufactured by Dow Chemical Co., epoxy equivalent of 175 g / equivalent) in a 1/1 mixed solvent of n-butanol and toluene. 50% by mass) was reacted at 80 ° C. while dropping the solution in the eggplant flask with a dropping funnel to obtain a reaction solution. Thereafter, 2-methylimidazole and the solvent were distilled off from the reaction solution under reduced pressure to obtain a curing agent 1 for comparative epoxy resin. The comparative epoxy resin curing agent 1 obtained had a weight average molecular weight of 3100 and a molecular weight distribution of 3.5. Curability and fluidity were evaluated using this comparative epoxy resin curing agent 1. The results obtained are summarized in Table 1.

(Comparative Example 2)
The autoclave was charged with 9 equivalents of monomethylamine and methanol to obtain a solution (concentration 60% by mass), and the temperature of the solution was maintained at 50 ° C. While slowly adding 1 equivalent (in terms of epoxy group) of bisphenol A type epoxy resin (Epon (R) 828 epoxide) to the solution under stirring, the reaction solution was obtained by reacting at 50 ° C. Then, the comparative epoxy resin curing agent 2 was obtained by distilling off monomethylamine and the solvent from the reaction solution under reduced pressure. The resulting epoxy resin curing agent 2 had a weight average molecular weight of 500 and a molecular weight distribution of 1.10. Curability and fluidity were evaluated using this comparative epoxy resin curing agent 2. The results obtained are summarized in Table 1.

(Comparative Example 3)
In Comparative Example 1, the same comparative epoxy was used except that 2.1 equivalents (in terms of active hydrogen) of N-methylpiperazine (manufactured by Wako Pure Chemical Industries, Ltd.) were used for 1 equivalent (in terms of epoxy group) of bisphenol A type epoxy resin. A resin curing agent 3 was obtained. The resulting curing agent 3 for comparative epoxy resin had a weight average molecular weight of 3500 and a molecular weight distribution of 3.7. Curability and fluidity were evaluated using this comparative epoxy resin curing agent 3. The results obtained are summarized in Table 1.

  The curable epoxy resin composition and the cured product thereof according to the present embodiment include a conductive material, an anisotropic conductive material, an insulating material, a sealing material, and a coating in addition to an adhesive and / or a bonding paste and a bonding film. It can be suitably used as a material, a coating composition, a prepreg, a heat conductive material and the like.

Claims (8)

(A) a compound having at least one epoxy group;
(B) a reaction product of a compound having at least one tertiary amino group and at least one active hydrogen group as a main component,
A curing agent for epoxy resin, wherein the molecular weight distribution (weight average molecular weight / number average molecular weight) of the reaction product is more than 1 and 1.5 or less.   The curing agent for epoxy resins according to claim 1, wherein the molecular weight distribution (weight average molecular weight / number average molecular weight) of the reaction product is more than 1 and 1.2 or less.   The hardening | curing agent for epoxy resins of Claim 1 or 2 whose weight average molecular weights of the said reaction product are 200-8000.   The curing agent for epoxy resins according to any one of claims 1 to 3, wherein the compound (B) having at least one tertiary amino group and at least one active hydrogen group is an imidazole or an imidazoline. It is a manufacturing method of the hardening | curing agent for epoxy resins of any one of Claims 1-4,
(A) For one equivalent of an epoxy group of a compound having at least one epoxy group, at least one equivalent of a compound having at least one tertiary amino group and at least one active hydrogen group is reacted in terms of active hydrogen to produce a reaction. Obtaining a product;
(B) purifying the obtained reaction product;
The manufacturing method of the hardening | curing agent for epoxy resins containing.   The curable epoxy resin composition containing the hardening | curing agent for epoxy resins of any one of Claims 1-4, and an epoxy resin.   An epoxy cured product obtained by curing the curable epoxy resin composition according to claim 6.   The manufacturing method of an epoxy hardened body including the process of hardening the curable epoxy resin composition of Claim 6.