JPS61192722A - Curable composition - Google Patents

Abstract

PURPOSE:The titled composition excellent in storage stability and curability, by mixing an epoxy resin with a specified compound with a surface-treated powder curing agent for epoxy resin. CONSTITUTION:100pts.wt. epoxy resin (A) having at least two epoxy groups in the molecule and a hydrolyzable chlorine content <=300ppm (e.g., bisphenol A diglycidyl ether) is mixed with 5-80pts.wt. at least one compound (B) selected from among a guanidine compound, an aromatic amine compound, a carboxylic acid anhydride compound and a hydrazide compound, 0.1-20pts.wt. compound (C) of an m.p. which is by 5-50 deg.C higher than that before coating, obtained by treating a powdered epoxy resin curing agent of an m.p. of 50-150 deg.C and a particle diameter <=50mu (e.g., m-phenylenediamine) with a surface-treating agent (e.g., tolylene diisocyanate) to form a 100-10,000Angstrom -thick film on the surface of the curing agent and, optionally, another curing agent, additives such as extender and reinforcement, an organic solvent, a (non)reactive diluent, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a one-component type epoxy resin composition. More specifically, it has excellent storage stability at room temperature,
The present invention also relates to a one-component type epoxy resin composition that cures in a short time under heat curing conditions and provides excellent curing performance.

[Conventional technology]

Epoxy resins are used in a variety of applications such as adhesives, paints, lamination, and casting due to their excellent physical properties. Epoxy resin compositions commonly used at present are of the so-called co-component type, in which two components, an epoxy resin and a curing agent, are mixed at the time of use. Although the one-component type epoxy resin composition can be cured at room temperature, it is necessary to store the epoxy resin and the curing agent separately.
Both materials must be measured and mixed as necessary before use, which is time-consuming and complicated to store and handle. Moreover, since the pot life is limited, it is not possible to mix large quantities, and when large quantities are used, the mixing frequency increases, resulting in a reduction in efficiency.

Several l-component epoxy resin compositions have been proposed in order to solve the drawbacks of these l-component epoxy resin compositions. For example, dicyandiamide, BF
3. Epoxy resin containing latent curing agents such as amine complexes and amine salts; epoxy resin and amine curing agents mixed together and immediately frozen to stop the reaction; amine/based curing There are methods in which the curing agent is microencapsulated and dispersed in the epoxy resin, and methods in which the curing agent is adsorbed on molecular sheep to suppress contact between the curing agent and the epoxy resin. However, the frozen type, microencapsulated type, molecular sieve type, etc. currently have extremely high manufacturing costs and are not satisfactory in terms of performance. Even in cases where latent curing agents are used, those with excellent storage stability require high temperatures for curing, and those that can be cured at relatively low temperatures have the disadvantage of poor storage stability, making them unsatisfactory in practical terms. It's not something you can do.

[Problems to be Solved by the Invention] Even in this current situation, many l-component type epoxy resin compositions using latent curing agents are seen because the curing agent is easy to handle and inexpensive.

However, as mentioned above, those with good storage stability have the disadvantage of poor curability, so various improvements have been made. For example, dicyandiamide is a latent curing agent that has been known for a long time, but when curing alone /7
A curing temperature of 0° C. or higher is required. In addition, the storage stability is 6 months or more at room temperature. In order to lower the curing temperature, it has been proposed to add a tertiary amino acid/compound, an i-dazole compound, a dimethylurea compound, etc. as an accelerator. As a result, although the curing temperature was lowered, the storage stability was poor and the latent potential of dicyandiamide was not fully utilized. Therefore, the emergence of l-component epoxy resin compositions containing accelerators that can lower the curing temperature without sacrificing the good storage stability properties of latent curing agents such as dicyandiamide is on the rise! ! It was desired.

The present inventors have made efforts to develop an epoxy resin composition that can overcome the drawbacks of conventional 1-component type epoxy resin compositions and can fully utilize the advantages of 4/component type epoxy resin compositions. After repeated research, the present invention was developed.

[Means for solving problems]

That is, the present invention provides (1) an epoxy resin, (2) one selected from guanidine compounds, aromatic amine compounds, carboxylic acid anhydride compounds, and hydrazide compounds, or a mixture thereof, and (8) a melting point of jO~/! A curable composition comprising a compound whose melting point after surface treatment is j-10°C higher than the melting point before surface treatment by adding a surface treatment agent to a curing agent for powdered epoxy resin at θ°C and performing surface treatment. It is related to.

The curable composition according to the present invention will be explained in more detail below.

The epoxy resin, which is the first component used in the present invention, is not particularly limited as long as it has an average number of epoxy groups of λ or more per molecule. For example, polyglycidyl ether obtained by reacting epichlorohydrin with polyhydric phenols such as bisphenol A1 bisphenol F, catechol, and resorcinol, or polyhydric alcohols such as glycerin and polyethylene glycol, or p-oxybenzoic acid and β-oxy Glycidyl ether ester obtained by reacting a hydroxycarboxylic acid such as naphthoic acid with epichlorohydrin, or polyglycidyl ester obtained by reacting epichlorohydrin with a polycarboxylic acid such as phthalic acid or terephthalic acid, or μ, μ A glycidylamine compound obtained by reacting epichlorohydrin with '-diaminodiphenylmethane, m-aminophenol, etc., and K includes, but is not limited to, epoxidized novolak resin, epoxidized cresol novolak resin, and epoxidized polyolefin. It's not a thing. A preferred epoxy resin is diglycidyl ether of bisphenol A. Also,
Hydrolyzable chlorine in epoxy resin greatly affects storage stability and curing properties, so JOOya
It is better that it does not exceed. More preferably, it does not exceed jOP.

In the present invention, the second component used is a guanidine compound, an aromatic amine compound, a carboxylic acid anhydride compound, a hydrazide compound, or a mixture thereof selected from among them.

The guanidine compounds used are, for example, dicyandiamide, methylguanidine, ethylguanidine, propylguanidine, butylguanidine, dimethylguanidine,
Examples include trimethylguanidine, phenylguanidine, diphenylguanidine, tolylguanidine, and the like. Aromatic amine compounds include, for example, diaminodiphenylmethane, diaminodiphenylsulfone, metaphenylenediamine, paraphenylenediamine, diaminotoluene, diaminoxylene, diaminodiphenylamine, diaminobiphenyl, bis(3-chloruda-aminophenyl)
Examples include methane and diaminobenzoic acid. Examples of carboxylic anhydride compounds include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, 3-chlorophthalic anhydride, -≠-chlorophthalic anhydride, and chlorophthalic anhydride. Examples include benzophenonetetracarboxylic acid, succinic anhydride, methylsuccinic anhydride, dimethylsuccinic anhydride, dichlorosuccinic anhydride, methylnazic acid, dodecylsuccinic acid, chlorendecic anhydride, maleic anhydride, and the like. Examples of the hydrazide compound include succinic acid hydrazide, adipic acid hydrazide, glutaric acid hydrazide, sepacic acid hydrazide, phthalic acid hydrazide, in7thalic acid hydrazide, terephthalic acid hydrazide, p-oxybenzoic acid hydrazide,
Examples include salicylic acid hydrazide, phenylaminopropionic acid hydrazide, maleic acid hydrazide, and the like.

The melting point of the third component used in the present invention is! 0-1j The original curing agent for powdered epoxy resin (hereinafter abbreviated as compound before surface treatment) is! It is particularly obtained by grinding a curing agent with a melting point of 0-/jOc. When the melting point of the pre-surface treatment compound is below j0° C., the powdered pre-surface treatment compound tends to aggregate during storage, making handling difficult.

At 750°C or higher, the desired short-time curing is poor. In order to obtain Qliil IC with excellent curing ease and storage stability, the preferred melting point is 4ON/20°C. Note that the melting point in the present invention refers to the temperature at which the substance begins to melt. The measurement method is JIS K 00 Hiroshi "Melting point measurement method for chemical products".

The melting point! θ~/! Examples of curing agents at θ°C include aromatic amine compounds such as metaphenylenediamine, paraphenylenediamine, and diaminodiphenylmethane;
Or acid anhydride compounds such as phthalic anhydride, 3-chlorophthalic anhydride, ≠-chlorophthalic anhydride, tetrahydrophthalic anhydride, dimethylsuccinic anhydride, or imidazole, comethylimidazole, cola/decylimidazole, μm methylimidazole, Examples include imidazole compounds such as cophenylimidazole.

In addition, as another example, the melting point obtained from the combination K with the following epoxy resin curing agent (4), a compound that reacts with (4), etc.)! ON/! This is the reaction product at 0℃,
Can be used as a pre-surface treatment compound.

(4) is an aliphatic amine compound such as ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, diethylaminopropylamine,
Or aromatic amine compounds such as metaphenylene diamine, diaminodiphenylmethane, diaminodiphenyl sulfone, bisaminomethyldiphenylmethane, or hexahydrophthalic anhydride, trimellitic anhydride, biromellitic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride W11 anhydride Carboxylic acid anhydride compounds such as succinic acid and dimethylsuccinic anhydride, or hydrazide compounds such as adipic acid hydrazide, succinic acid hydrazide, sepacic acid hydrazide, and terephthalic acid hydrazide, or dicyandiamide, or J-methylimidazole, -monoethylimidazole, coisoglobilimidazole, codedecyl ζdazole, cola/decylimidazole,
Examples include imidazole compounds such as 2-phenylimidazole and -1ethyl-lymethylimidazole, and carbonate salts of al or imidazole compounds.

(3) is a carboxylic acid compound of succinic acid, adipic acid, sebacic acid, phthalic acid, terephthalic acid, dimer acid,
Alternatively, sulfonic acid compounds such as ethanesulfonic acid and p-toluenesulfonic acid, or incyanate compounds such as tolylene diisocyanate, μ'-diphenylmethane diisocyanate, and hexamethylene diisocyanate, or p-hydroxystyrene resin and phenol resin. , epoxy resin, etc. The reaction between (4) and (Bl) can be carried out by a conventionally known general synthesis method, and the melting point can also be controlled by controlling the reaction amount of (Bl).

If the melting point of the compound before surface treatment is 10-110°C, the curing agent may be appropriately selected from the above-mentioned curing agents, but it is preferable that at least λ amino group active hydrogens be present in 7 molecules of the compound before surface treatment. or one or more of 7 tertiary amide groups in 7 molecules of the compound before surface treatment. Examples of compounds having j or more amino group active hydrogens include the above-mentioned aromatic amine compounds having a melting point of 0 to 10°C, epoxy resin adducts of ethylenediamine, epoxy resin adducts of diethylenetriamine, and triethylenetetramine. Adducts of aliphatic amines and epoxy resins, such as epoxy resin adducts, epoxy resin adducts of tetraethylenepentamine, epoxy resin adducts of hexamethylene diamine, epoxy resin adducts of diethylaminopropylamine, or aliphatic amines and dicarboxylic adducts. Examples include acid condensates, polyureas such as aliphatic amine and tolylene diisocyanate adducts, aliphatic amine hexamethylene diisocyanate adducts, and modified products such as succinic acid hydrazide, adipic acid hydrazide, and dicyandiamide. As having one or more tertiary amino groups,
For example, the above-mentioned imidazole compound having a melting point of θ~/jθ℃, an adduct of an imidazole compound and an epoxy resin, an epoxy resin adduct of a carboxylate of an imidazole compound, an epoxy resin adduct of dimethylamine, an epoxy resin adduct of diethylamine, etc. Compounds with secondary amino groups, such as epoxy resin adducts, epoxy resin adducts of dipropylamine, epoxy resin adducts of di(hydroxymethyl)amine, and epoxy resin adducts of di(hydroxyethyl)amine, and epoxy resins. Examples include additives of .

The reaction of these curing agents can be carried out by conventionally known general synthesis methods, and the melting point can also be controlled by controlling the amount of reactants reacted.

Among these compounds before surface treatment, in order to obtain a compound with particularly excellent curing ease and storage stability, K has t-1 or more hydroxyl groups in one molecule of the compound before surface treatment. Particularly preferred are imidazole derivatives. Examples of such compounds include adducts of imidazole compounds or carboxylic acid salts of imidazole compounds and epoxy compounds having seven or more epoxy groups in one molecule.

The imidazole compounds used include imidazole,
! Examples thereof include -methylimidazole, 2-ethylimidazole, Coethyl-Hiro-methylimidazole, 1-inpropylimidazole, λ-undecylimidazole, 2-phenylimidazole, and their carboxylic acid salts.

Examples of carboxylic acids include acetic acid, lactic acid, salicylic acid, benzoic acid, adipic acid, heptatalic acid, citric acid, tartaric acid, maleic acid, trimellitic acid, and the like. The epoxy compounds used include monoepoxy compounds such as butyl glycidyl ether, hexyl glycidyl ether, phenyl glycidyl ether, p-xyl glycidyl ether, glycidyl acetate, glycidyl butyrate, glycidyl hexoate, glycidyl benzoate, or There are epoxy resins listed as the first component of the present invention. In order to obtain excellent curability and storage stability, K is used as an imidazole compound such as 2-methylimidazole or F.
One selected from i2-ethyl-Hiro-methylimidazole or a mixture thereof is preferred, and as the epoxy compound, an epoxy resin obtained by reacting bisphenol A and epichlorohydrin is most preferred.

This reaction of the adduct of the imidazole compound and the epoxy compound can be carried out by a conventionally known general method. The melting point can also be controlled by controlling the amount of reaction between the imidazole compound and the epoxy compound.

Although there is no particular restriction on the particle size of the powdered epoxy resin compound used in the present invention, if the particle size is too large, curing properties may be delayed or the physical properties of the cured product may be impaired. Preferably, the average particle size is 10 μm or less; if the average particle size becomes larger than this, chemical resistance and mechanical strength of the cured product will deteriorate. Optimally! It is less than μ.

The particle size in the present invention refers to the Stokes diameter measured by the centrifugal sedimentation method or sedimentation method as shown in the table in "Agglutination Engineering" (published in 1932) edited by the Japan Powder Industry Technology Association and Hironaka. do. It also refers to the average particle diameter and mode diameter.

The shape of the powdered epoxy resin compound used in the present invention is not particularly limited, but it is preferably non-spherical in view of ease of curing. In order to obtain a non-spherical shape, K may be mechanically crushed. For example,
A hammer mill, jet crusher, ball mill, etc. may be used.

Examples of the surface treatment agent used in the present invention include the following. For example, carboxylic acid compounds such as formic acid, acetic acid, propionic acid, butyric acid, adipic acid, succinic acid, phthalic acid, terephthalic acid, or ethanesulfone.
1, sulfonic acid compounds such as p-toluenesulfonic acid, or phenyl isocyanate, Hiroshi, μ'-diphenylmethane diinocyanate, tolylene diisocyanate,
Isocyanate compounds such as hexamethylene diisocyanate, acid chlorides such as acetyl chloride, propionic acid chloride, succinic acid chloride, and adipic acid chloride, or acid anhydrides such as acetic anhydride, propionic anhydride, and phthalic anhydride. Examples include compounds, epoxy compounds having one or more epoxy groups, p-hydroxystyrene resins, phenol resins, and the like. Preferably 7
It is a compound having one or more isocyanate groups in the molecule. Particularly preferred is tolylene diinocyanate, or one selected from Hiroshi and .mu.'-diphenylmethane diisocyanate, or a mixture thereof, which can provide excellent storage stability and curability.

In the present invention, the method of surface treatment by adding a surface treatment agent to the compound before surface treatment includes, for example, a method of dispersing the compound before surface treatment in a solvent that does not dissolve it and adding a surface treatment agent, or a method of adding a surface treatment agent to the compound before surface treatment; There is a method of keeping the pre-compound in a fluid state in an air stream and then spraying the surface treatment agent.

In the present invention, making the melting point of the compound after surface treatment higher than the melting point of the compound before surface treatment is as follows:
Due to storage stability and curing properties, it is extremely [11! That's true. In other words, if the melting point of the compound after surface treatment is lower than the melting point of the compound before surface treatment, there is not much difference in curability before and after surface treatment, but in terms of storage stability, No improvement was seen in the compound after surface treatment, making it unsuitable for summer use. When the difference in melting point before and after surface treatment is 50° C. or more, the storage stability of the compound after surface treatment is very good, but the curability is significantly inferior to that of the compound before surface treatment. This difference in melting point can be controlled by the type or amount of the pre-surface treatment compound and surface treatment agent. From the viewpoint of curability and storage stability, a particularly preferable melting point difference is 10-0°C.

In the present invention, the thickness of the film formed by the surface treatment agent is determined from the viewpoint of curability and storage stability, and is preferably between 100 and 10,000 yen. 10
If it is below 0^, the storage stability will not be improved and toooo X
Above this, the curability is significantly inferior to that of the compound before surface treatment. The thickness of the film here is observed by slicing the surface-treated compound and using a transmission electron microscope. Particularly preferable film thicknesses in terms of curability and storage stability are:
2oo-iooo''A.

The epoxy resin composition of the present invention can be obtained by simply uniformly mixing the epoxy resin as the first component, the guanidine compound as the second component, and the surface-treated third component.

The mixing amount is determined from the viewpoint of curability and cured physical properties, but preferably 1 to 10 parts by weight of dicyandiamide, etc., as the second component, and 1 to 10 parts by weight of dicyandiamide, etc., as the second component, per 10 parts by weight of the epoxy resin as the first component. Compound 0 after surface treatment. /-20 parts by weight.

That is, the second component is less than 5 parts by weight, and the third component is 0.7 parts by weight.
If it is less than 1 part by weight, it takes a very long time to obtain sufficient curing performance, which is impractical. Also, the second component is ♂
When the amount of O and the third component exceeds 20 parts by weight, the viscosity of the blend becomes high and handling becomes difficult.

In the epoxy resin composition of the present invention, other curing agents may be used in combination with #i, if desired. Examples include phenol resin, melamine resin, and area resin.

Extenders, reinforcing agents, fillers, pigments, and the like can be added to the epoxy resin composition of the present invention, if desired. 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, pent/, silica, aerosol, litho/, palite, titanium trioxide, carbon black, graphite, iron oxide, gold, aluminum powder, iron powder These can be used effectively depending on the purpose.

An organic solvent, a reactive diluent, a non-reactive diluent, a modified epoxy resin, etc. can be added to the epoxy resin composition of the present invention, if desired. Examples of organic solvents and 1-solvents include toluene, xylene, methyl ethyl ketone, methyl imbutyl ketone, ethyl acetate, butyl acetate, and the like. Examples of the reactive diluent include butyl glycidyl ether, N,N'-diglycidyl-〇-)luidine, phenyl glycidyl ether, styrene oxide, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, /, 6-hexane. Examples include thiol diglycidyl ether and the like. Examples of the non-reactive diluent include dioctyl phthalate, dibutyl heptathalate, dioctyl adipate, petroleum solvents, and the like. Examples of the modified epoxy resin include 1-urethane modified epoxy resin, rubber modified epoxy resin, and alkyd modified epoxy resin.

〔Effect of the invention〕

The epoxy resin composition of the present invention obtained in this way has excellent storage stability at room temperature, has greatly improved curability compared to conventional/component type epoxy resin compositions, and has good performance. This gives a cured product having the following properties.

The epoxy resin composition of the present invention provides excellent cured physical properties and can be used in a wide range of fields. For example, in the automotive field, adhesives are used to bond headlights, gasoline tanks, hemming flanges of bonnets, etc., and to join steel plates for bodies and roofs.In the electrical field, speaker magnets are bonded, motor coils are impregnated, etc. Examples include adhesives for adhesives, tape heads, batteries, fluorescent lamp ballasts, and bonding adhesives in the electronic field. In the paint field, powder paints and special fields include solder resist inks and conductive paints.

It can also be used for electrical insulating materials, laminated structures, etc.

〔Example〕

The present invention will be explained below with reference to examples, but the scope of the present invention is not limited by these examples. "Parts" in the examples indicate parts by weight.

Reference example 1 Coechyl-Hiro-Methylimidazole and AER44/
(manufactured by Asahi Kasei Corporation, bisphenol A type epoxy resin,
The adduct with epoxy equivalent ('t70) (reaction molar ratio 1) was coarsely pulverized to about 20 meshes and then finely pulverized to obtain a surface-treated compound with an average particle size J of 0μ. The melting point of this product is 100°C.

After surface treatment, 100 parts of the compound was dispersed in 200 parts of xylene, and v parts of succinic chloride were added to the mixture while stirring at 10°C. This was continued for 2 hours, and then the yarn was vacuumed to remove xylene, resulting in a surface-treated compound. The melting point of this product is 123°C. This is designated as Compound A after surface treatment.

Reference Example 2 Coundecyl imidazole and AER330 (manufactured by Asahi Kasei Kogyo ■, bisphenol A!!! epoxy resin.

Epoxy equivalent/11) adduct (reaction molar ratio
) was coarsely pulverized to about 20 meshes and then finely pulverized to obtain a pre-surface-treated compound with an average particle size of zμ.

The melting point of this product is 0°C.

100 m of this pre-surface-treated compound was dispersed in 100 m of toluene, and 5.0 parts of phenyl glycidyl ether was added thereto while heating and stirring at 0°C. Continue like that for 7 hours, then-
The mixture was filtered and dried under reduced pressure to obtain a surface-treated compound. The melting point of this product is 113°C.

This is designated as Compound B after surface treatment.

Reference example 3! - An adduct of phenylimidazole and DzNuJ/ (manufactured by Dow Chemical Company, phenol novolac type epoxy resin, epoxy equivalent: 71) (reaction molar ratio j:l) was coarsely ground to about 20 meshes, then finely ground to give an average Particle size! Obtain the compound before surface treatment of μ.9. The melting point of this material is 10'°C.

700 parts of this pre-surface-treated compound was dispersed in 230 parts of hexane, and 3 parts of xylylene diisocyanate was added while stirring at 40°C. This was continued for 1 hour, then filtered and dried under reduced pressure to obtain a surface-treated compound. The melting point of this product is 120°C.

This is designated as Compound C after surface treatment.

Reference example≠ An adduct of triethylenetetramine and AER/, 4/ (reaction molar ratio 2:l) was coarsely ground to about 20 meshes and then finely ground to form a compound with an average particle size of J, jμ before surface treatment. Obtained. The melting point of this product is tr°C.

100 parts of this pre-surface-treated compound was dispersed in 200 parts of hexane, and 3.5 parts of Hiro'-diphenylmethane diinocyanate was added while stirring at 21°C. This was continued for 3 hours, then filtered and dried under reduced pressure to obtain a surface-treated compound. The melting point of this product is 103°C.

This is used as a compound after surface treatment.

Example 1-6. Comparative Examples 1 to 3 The amounts shown in Table 1 were blended with 100 parts of AER33/ (manufactured by Asahi Kasei Kogyo ■, bisphenol A type epoxy resin, epoxy equivalent II). Using this composition,
Gel time and storage stability were measured. Table 7 shows the results.
Shown below.

In addition, as a comparative example, a composition in which only dicyandiamide was blended in 100 parts of AERJj/, and a composition in which the amount of xylylene diisocyanate was o parts in reference example 3 (compound E after surface treatment, melting point 10 r ° C.), The same test as in the example was conducted by adding r parts of xylylene diisocyanate (compound F after surface treatment, melting point/Aθ°C). The results are shown in Table-/.

(Evaluation method) Gel time: Place the composition on an iron plate at each temperature,
Indicates the time it takes to stop stringing.

Storage stability: shows a period during which the viscosity increase of the composition is less than 1 times as large at each temperature.

(Leaving space below) Procedural amendment (voluntary) April 2, 1985, 1988 Patent Application No. 31439 2, Title of invention: Curable composition 3 Relationship with the case of the person making the amendment: Patent applicant's 5th complaint 1-2-6-4 Dojimahama, Kita-ku, Osaka-shi, Osaka Prefecture; Agent address: 5B8 Katsushin Building, 3-7 Yotsuya, Shinjuku-ku, Tokyo.
, Contents of the amendment (as attached) The description of the details of the amendment will be amended as follows.

(11 page 7 lines 15-17 [methylsuccinic anhydride,...dodecylsuccinic acid,"
is corrected to "methyl succinic anhydride, dimethyl succinic anhydride, dichlorosuccinic anhydride, methyl nadic anhydride, dodecyl succinic anhydride."

(2) From page 7, line 19 to page 8, line 3, “succinic acid hydrazide, terephthalic acid hydrazide,” is replaced with “succinic acid dihydrazide, adipic acid dihydrazide, glutaric acid dihydrazide, sebacic acid dihydrazide, phthalic acid dihydrazide, isophthalic acid dihydrazide,” Acid dihydrazide, terephthalic acid dihydrazide,” he corrected.

(3) On page 8, line 5, "maleic acid hydrazide" is corrected to "maleic acid dihydrazide."

14) Lines 914 to 5 “dimethylsuccinic anhydride” is replaced with “
Dimethylsuccinic anhydride” is corrected.

(5) On page 9, line 5, "acid anhydride compounds" is corrected to "carboxylic acid anhydride compounds."

(6) On page 10, lines 4 to 6, "Adipic acid hydrazide, succinic acid hydrazide, sebacic acid hydrazide, terephthalic acid hydrazide" is corrected to "adipic acid dihydrazide, succinic acid dihydrazide, sebacic acid dihydrazide, terephthalic acid dihydrazide".

(7) Page 12, lines 5 and 6, “succinic acid hydrazide, adipic acid hydrazide,” was changed to “succinic acid dihydrazide, adipic acid dihydrazide,”
I am corrected.

(8) On page 16, line 9, "acid anhydride compound" is corrected to "carboxylic acid anhydride compound."

(9) From page 17, line 20 to page 18, line 1, “The thickness of the film formed by the surface treatment agent” is changed to “by adding the surface treatment agent to the pre-surface treatment compound and performing the surface treatment, A film is formed on the surface of the compound.The thickness of the formed film is "."

am Page 18, after line 9 and before line 10, insert the following statement.

"In the present invention, the difference in melting point between the compound before surface treatment and the compound after surface treatment is presumed to be due to an apparent increase in melting point due to the formation of a film on the compound before surface treatment.

”

Claims (1)

[Scope of Claims] 1. (1) an epoxy resin, (2) one or a mixture thereof selected from a guanidine compound, an aromatic amine compound, a carboxylic acid anhydride compound, a hydrazide compound, and (3) a melting point. By adding a surface treatment agent to a powdered epoxy resin curing agent with a temperature of 50 to 150°C, the melting point after surface treatment is 5 to 5% higher than that before surface treatment.
A curable composition comprising a compound with a temperature higher than 0°C.