JP2000063490A - Curable epoxy resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an epoxy resin composition excellent in solubility in a weak solvent such as terpene, mineral spirits and the like and having curability, solvent resistance, flexibility and high anti-corrosive property. SOLUTION: The objective composition comprises a Mannich compound (A) obtained by reacting (a) a polyamine compound, (b) formaldehyde compounds and (c) a phenol compound bearing at least a 10 carbon atom-containing long chain aliphatic or an alicyclic hydrocarbyl group, and an epoxy compound (B). Preferably, (a) the polyamine compound is m-xylylenediamine and the Mannich compound (A) is the one obtained by reacting 1 mole of (a) the polyamine compound with 0.3-2 mole of (b) the formaldehyde compounds and (c) 0.3-2 mole of the phenol compound.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a curable epoxy resin composition, and more specifically to a Mannich compound obtained by reacting a polyamine compound, formaldehydes and a long chain aliphatic or alicyclic hydrocarbon group-substituted phenol compound. Characterized by being used as a curing agent, it is soluble in highly safe and high boiling point and hypoallergenic solvents such as terpen and mineral spirits, and has excellent weather resistance, corrosion resistance, curability and adhesion to various substrates. The present invention relates to a curable epoxy resin composition capable of providing a good coating film.

[0002]

BACKGROUND OF THE INVENTION Epoxy resins are excellent in adhesion to various substrates, heat resistance, chemical resistance, electrical properties, mechanical properties, etc.
Widely used as an adhesive, etc.

When used in these applications, a solvent type in which an epoxy resin is dissolved in various low boiling point solvents has been generally used. However, there is a risk of fire, harmfulness to human body,
Due to problems such as adverse effects on the global environment, the use of low boiling point solvents has come to be restricted, and it is possible to reduce the use of solvents or switch to high boiling point and low irritating solvents (so-called weak solvents) such as terpen and mineral spirits. I was strongly sought after.

In order to obtain such a weak solvent-soluble type epoxy resin composition, a method of using a weak solvent-soluble type epoxy resin as a main component or a weak solvent-soluble type epoxy resin as a curing agent is used. A method of using one can be considered.

To date, many epoxy resins which are soluble in weak solvents have been proposed, for example, JP-A-3-11.
Japanese Patent No. 5318 proposes to provide a coating material in which an epoxy resin obtained by modifying an epoxy resin having an epoxy equivalent of 250 or less with an aliphatic monomer acid and crosslinking it with a diisocyanate compound is soluble in mineral spirits. JP-A-134175 proposes an epoxy resin composition obtained by adding a phenol compound containing a terpene structure skeleton to an epoxy resin.
JP-A-9-22782 proposes a long-chain alkyl-substituted phenol novolac epoxy resin.
Japanese Patent Laid-Open No. 5 (1994) proposes an epoxy resin obtained by reacting a long-chain phenol novolac with a bifunctional epoxy resin.

On the other hand, the hardeners are the aliphatic polyamines, aromatic polyamines, polyamides, cycloaliphatic polyamines, amino-substituted aliphatic alcohols, and the like which are conventionally known as hardeners. Phenol and adducts with low molecular weight epoxy have poor solubility in terpenes and mineral spirits, and alternative hardeners that are soluble in weak solvents with high boiling points and mildness have not been proposed. It was

Therefore, an object of the present invention is to provide an epoxy resin composition having excellent solubility in weak solvents such as terpenes and mineral spirits, and exhibiting curability, solvent resistance, flexibility and high corrosion resistance. It is in.

[0008]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that a Mannich compound obtained by reacting a polyamine compound, formaldehyde and a long-chain alkyl- or alicyclic hydrocarbon-substituted phenol as a curing agent. It was found that the epoxy resin composition used can achieve the above object.

The present invention was made based on the above findings, and has (a) a polyamine compound, (b) formaldehyde and (c) a long-chain aliphatic or alicyclic hydrocarbon group having 10 or more carbon atoms. A curable epoxy resin composition comprising a Mannich compound (A) and an epoxy compound (B) obtained by reacting a phenol compound.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The curable epoxy resin composition of the present invention will be described in detail below.

The Mannich compound which is the component (A) used in the curable epoxy resin composition of the present invention is used as a curing agent. The polyamine compound which is the component (a) used in the production of the above Mannich compound is, for example, a compound having two or more primary or secondary amino groups in the molecule, such as ethylenediamine and hexamethylenediamine. Alkylenediamine;
Polyalkylenepolyamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine;
Alicyclic polyamines such as 1,2-diaminocyclohexane, 1,4-diamino3.6-diethylcyclohexane and isophoronediamine; Heterocyclic polyamines such as 1,4-bis (3-aminopropyl) piperazine; m-xylyl Examples thereof include aromatic polyamines such as diamine, diaminodiphenylmethane and diaminodiphenylsulfone, and these may be used alone or as a mixture.
In particular, m-xylylenediamine has the following properties:
It is preferable because it has excellent solvent resistance and corrosion resistance.

Further, as the formaldehyde which is the component (b) used in the production of the above-mentioned Mannich compound,
Examples thereof include formaldehyde and formaldehyde-releasing substances such as trioxane and paraformaldehyde.

Examples of the phenol compound having a long-chain aliphatic or alicyclic hydrocarbon group having 10 or more carbon atoms, which is the component (c) used in the production of the Mannich compound, include decylphenol and Decylphenol, dodecylphenol, tridecylphenol, tetradecylphenol, pentadecylphenol, pentadecenylphenol, pentadecadienylphenol, pentadecatrienylphenol, hexadecylphenol, heptadecylphenol, octadecylphenol, octadecene Examples thereof include nylphenol, terpenephenol and the like, and a mixture thereof, or a mixture of these naturally occurring substances such as cardanol.

Here, the terpene phenol is obtained by adding an alkylphenol compound such as phenol or orthocresol to a cyclic terpene compound. For example, the following [Chemical formula 1]-(6) And the like.

[0015]

[Chemical 1]

The method of reacting these components (a), (b) and (c) to obtain a Mannich compound is not particularly limited, but for example, a mixture of the components (a) and (c) is used. In addition, the component (b) is 80 ° C. or lower, preferably 6
Examples thereof include a method of adding at 0 ° C. or lower, then raising the temperature to 80 to 180 ° C., preferably 90 to 150 ° C., and reacting for 1 to 10 hours while removing the distillate from the reaction system.

Here, for 1 mol of the component (a), (b)
The component is preferably 0.3 to 2 mol, more preferably 0.
When it is used in the range of 5 to 1.5 mol and the amount of the component (b) used is less than 0.3 mol, the addition may not proceed sufficiently and the physical properties such as low temperature curing property or anticorrosion property may be deteriorated. If it is used in excess of 2 moles, polymerization will occur to a large extent, the viscosity may become too high, and the crosslinking density after curing may decrease, such being undesirable. Further, the component (c) is preferably used in an amount of 0.3 to 2 mol, and more preferably 0.5 to 1.5 mol, based on 1 mol of the component (a). Whitening may occur (amine brushing), and if it is used in excess of 2 moles, the active sites may be insufficient and the ability as a curing agent may not be sufficiently exhibited, which is not preferable.

Examples of the epoxy compound which is the component (B) used in the curable epoxy resin composition of the present invention include, for example, polynuclear polyphenol compounds such as hydroquinone, resorcin, pyrocatechol and phloroglucinol. Glycidyl ether compound; dihydroxynaphthalene, biphenol, methylenebisphenol (bisphenol F), methylenebis (orthocresol), ethylidene bisphenol, isopropylidene bisphenol (bisphenol A), isopropylidene bis (orthocresol), tetrabromobisphenol A, 1,
3-bis (4-hydroxycumylbenzene), 1,4-
Bis (4-hydroxycumylbenzene), 1,1,3-
Tris (4-hydroxyphenyl) butane, 1,1,
Polynuclear polyvalents such as 2,2-tetra (4-hydroxyphenyl) ethane, thiobisphenol, sulfobisphenol, oxybisphenol, phenol novolac, orthocresol novolac, ethylphenol novolac, butylphenol novolac, octylphenol novolac, resorcinol novolac, and terpene diphenol. Polyglycidyl ether compounds of phenolic compounds;
Ethylene glycol, propylene glycol, butylene glycol, hexanediol, polyglycol, thiodiglycol, glycerin, trimethylolpropane,
Polyglycidyl ethers of polyhydric alcohols such as pentaerythritol, sorbitol, bisphenol A-ethylene oxide adducts; maleic acid, fumaric acid, itaconic acid, succinic acid, glutaric acid, suberic acid, adipic acid, azelaic acid, sebacic acid, dimer Aliphatic, aromatic or alicyclic compounds such as acids, trimeric acid, phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid, pyromellitic acid, tetrahydrophthalic acid, hexahydrophthalic acid, endomethylenetetrahydrophthalic acid Homopolymers or copolymers of glycidyl esters of polybasic acids and glycidyl methacrylate; N, N-diglycidylaniline, glycidylamino groups such as bis (4- (N-methyl-N-glycidylamino) phenyl) methane Having epoxidation Things; vinylcyclohexene diepoxide, di cyclopentane diepoxide, 3,4
-Epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6
-Methylcyclohexylmethyl-6-methylcyclohexanecarboxylate, bis (3,4-epoxy-6-
Examples include epoxidized products of cyclic olefin compounds such as methylcyclohexylmethyl) adipate; epoxidized conjugated diene polymers such as epoxidized polybutadiene and epoxidized styrene-butadiene copolymers, and heterocyclic compounds such as triglycidyl isocyanurate. Further, these epoxy resins may be internally cross-linked with a prepolymer having a terminal isocyanate.

Among the above epoxy compounds, an epoxy compound which is soluble in a weak solvent is preferable, that is, an epoxy compound having an aliphatic or alicyclic hydrocarbon group having 4 or more carbon atoms is preferable. Examples of such an epoxy compound include a phenol novolac epoxy resin substituted by an aliphatic or alicyclic hydrocarbon group having 4 or more carbon atoms which may be crosslinked with a polyisocyanate compound; 115318, JP-A-8-134175, and JP-A-9-126.
No. 78, JP-A-9-227825, an epoxy resin as proposed; ADEKA RESIN EP-9100
(Asahi Denka Co., Ltd.), Haripol EP-450 (Harima Kasei Co., Ltd.), and other commercially available weak solvent type epoxy resins are preferable.

The epoxy compound preferably has an epoxy equivalent of 100 to 2000, more preferably 150 to 1500. When the epoxy equivalent is less than 100, the curability may decrease, and when it is greater than 2000,
It is not preferable because sufficient physical properties of the coating film may not be obtained.

The Mannich compound (A) is preferably added in an amount of 1 to 5 with respect to 100 parts by weight of the epoxy compound (B).
0 parts by weight, more preferably 5 to 30 parts by weight,
If it is less than 1 part by weight, curing may not proceed, and if it exceeds 50 parts by weight, amine brushing may occur, which is not preferable.

Further, the curable epoxy resin composition of the present invention may be used in combination with generally known epoxy curing agents. Examples of these known curing agents include the polyamine compounds exemplified as the above-mentioned component (a) and Examples thereof include epoxide addition modified products, amidation modified products, Mannich modified products, and the like. Here, the epoxide addition modified product is
By reacting a polyamine compound with various epoxy compounds such as glycidyl ethers such as phenyl glycidyl ether, butyl glycidyl ether, bisphenol A-diglycidyl ether, bisphenol F-diglycidyl ether or carboxylic acid glycidyl esters by a conventional method. The amidated modified product is produced by reacting a polyamine compound and a carboxylic acid such as dimer acid by a conventional method, and the Mannich modified product is a polyamine compound and an aldehyde such as formaldehyde and phenol, cresol,
It is produced by reacting a phenol such as xylenol, tert-butylphenol, resorcin or the like with at least one aldehyde reaction site in the nucleus by a conventional method.

The curable epoxy resin composition of the present invention comprises
Examples of the solvent include ketones such as methyl ethyl ketone, methyl amyl ketone, diethyl ketone, acetone, methyl isopropyl ketone, propylene glycol monomethyl ether acetate and cyclohexanone; tetrahydrofuran, 1,2-dimethoxyethane, 1,2-diethoxyethane and the like. Ethers; esters such as ethyl acetate and n-butyl acetate; alcohols such as iso- or n-butanol, iso- or n-propanol and amyl alcohol; aromatic hydrocarbons such as benzene, toluene and xylene; tetrachloride Halogenated aliphatic hydrocarbons such as carbon, chloroform, trichloroethylene, methylene chloride; halogenated aromatic hydrocarbons such as chlorobenzene; aniline, triethylamine, pyridine, dioxane, acetic acid,
Acetonitrile, carbon disulfide, etc. can be used, but the curable epoxy resin composition of the present invention can be used for terpene oils, terpene hydrocarbon oils such as D-limonene and pinene; mineral spirits, Swazol # 310 (Cosmo Matsuyama Oil Co., Ltd. )), Solvesso # 100 (Exxon Chemical Co., Ltd.)
High-boiling point paraffinic solvents such as (may also contain alicyclic and aromatic hydrocarbons containing aliphatic hydrocarbon as a main component. Here, high-boiling point means that 90% or more of components having a boiling point of 150 ° C. or higher). It is characterized in that it can be dissolved or dispersed in, and the like, and it is preferable to use these because the danger and the harmfulness can be reduced. Further, these solvents can be optionally used as a mixed solvent of two or more kinds.

The amount of the organic solvent used is preferably 0 to 200 parts by weight, more preferably 30 to 150 parts by weight, based on 100 parts by weight of the total amount of the epoxy compound and the curing agent. If the amount used exceeds 200 parts by weight, it volatilizes to cause danger and harm, which is not preferable.

Particularly, it is preferable to contain 10 to 600 parts by weight of at least one high boiling point paraffinic solvent or terpene type hydrocarbon oil, relative to 100 parts by weight of the resin component.

Further, the curable epoxy resin composition of the present invention can be improved in physical properties such as impact resistance by using monoglycidyl ethers in combination as a reactive diluent. Examples of these monoglycidyl ether compounds include phenol, cresol, ethylphenol, propylphenol, p-tert-butylphenol,
Monoglycidyl ethers such as p-tertiary amylphenol, hexylphenol, octylphenol, nonylphenol, dodecylphenol, octadecylphenol or terpenephenol are mentioned, and particularly, they are nucleated by an aliphatic or alicyclic hydrocarbon group having 4 or more carbon atoms. Substituted phenol monoglycidyl ethers are preferred because of their excellent solubility in weak solvents.

The curable epoxy resin composition of the present invention comprises
A non-reactive diluent such as dioctyl phthalate, dibutyl phthalate, benzyl alcohol or coal tar can be used in combination.

Further, the curable epoxy resin composition of the present invention contains, if necessary, glass fiber, carbon fiber, cellulose, silica sand, cement, kaolin, clay, aluminum hydroxide, bentonite, talc, silica, fine particles. Powdered silica, titanium dioxide, carbon black, graphite,
Fillers or pigments such as iron oxides and bituminous substances; thickeners;
Thixotropic agent; flame retardant; antifoaming agent; anticorrosive agent; usual additives such as colloidal silica and colloidal alumina may be added, and also adhesive resins such as xylene resin and petroleum resin are used together. You can also

The curable epoxy resin composition of the present invention is a paint or adhesive for concrete, cement mortar, various metals, leather, glass, rubber, plastic, wood, cloth, paper, etc .; adhesive tape for packaging, adhesive Labels, frozen food labels, removable labels, POS labels, adhesive wallpaper, adhesives for adhesive flooring materials; art paper, lightweight coated paper, cast coated paper, coated paperboard, carbonless copying machines, processed paper such as impregnated paper; natural Fibers, synthetic fibers, glass fibers, carbon fibers, metal fibers and other sizing agents, anti-fray agents, processing agents and other fiber treatment agents; sealing materials, cement admixtures,
It can be used for a wide range of applications such as building materials such as waterproof materials.

[0030]

EXAMPLES Hereinafter, the curable epoxy resin composition of the present invention will be described in more detail with reference to Production Examples and Examples.
The present invention is not limited to these.

Production Example 1 (Production of Mannich Compound) 136.0 g of metaxylylenediamine was placed in a flask equipped with a heating, cooling device, stirring device, dropping device, and dehydration device.
(1.0 mol) and terpene phenol (Yasuhara Chemical Co .; YP-90LL, hydroxyl equivalent 330) 29
7 g (0.9 mol) was charged, stirring was started, and 72.9 g (0.9 mol) of 37% by weight aqueous formalin solution was added dropwise over 60 to 120 minutes while adjusting the system temperature to 30 to 50 ° C. . After completion of the dropping, a dehydrator was attached, the temperature was gradually raised, and the reaction was allowed to proceed at 100 to 150 ° C. for 5 hours while distilling off water produced in the reaction. Finally at 110 ℃, 80
The dehydration reaction was completed under reduced pressure of mmHg, and the final product was a transparent brown semi-solid with an amine value of 260 mgKO.
440 g of H / g Mannich compound (A) was obtained.

Production Example 2 (Production of Mannich Compound) 136.0 g of metaxylylenediamine was placed in a flask equipped with a heating, cooling device, stirring device, dropping device, and dehydration device.
(1.0 mol) and cardanol (manufactured by Card Light Corporation; Card Light NX-4708, hydroxyl equivalent 300) 270 g (0.9 mol) were charged, stirring was started, and the system temperature was adjusted to 30 to 50 ° C. Meanwhile, 72.9 g (0.9 mol) of 37% by weight aqueous formalin solution was added to 60%.
Dropped over ~ 120 minutes. After completion of the dropping, a dehydrator was attached, the temperature was gradually raised, and the reaction was allowed to proceed at 100 to 150 ° C. for 5 hours while distilling off water produced in the reaction. Finally, the dehydration reaction was completed at 110 ° C. under a reduced pressure of 80 mmHg, and the final product was a brown liquid with a viscosity of 10 ps.
415 g of a Mannich compound (B) having a amine value of 271 mg / KOH at / 25 ° C was obtained.

Production Example 3 (Production of Mannich Compound) 136.0 g of metaxylylenediamine was placed in a flask equipped with a heating, cooling device, stirring device, dropping device and dehydrating device.
(1.0 mol), terpene phenol 148.5 g
(0.45 mol) and 135 g of cardanol (0.4
5 mol) was added, stirring was started, and the temperature in the system was adjusted to 30 to 5
A 37% by weight aqueous formalin solution 72.
9 g (0.9 mol) was added dropwise over 60 to 120 minutes.
After the dropping is complete, attach a dehydrator and gradually raise the temperature to 100
The reaction was allowed to proceed for 5 hours at ˜150 ° C. while distilling off the water produced in the reaction. Finally, the dehydration reaction was completed at 110 ° C. under a reduced pressure of 80 mmHg, and the final product was a brown liquid with a viscosity of 10 ps / 25 ° C. and an amine value of 266 m.
432 g of a Mannich compound (C) of g / KOH was obtained.

Production Example 4 (Production of Mannich compound) 136.0 g of metaxylylenediamine was placed in a flask equipped with a heating, cooling device, stirring device, dropping device and dehydrating device.
(1.0 mol), terpene phenol 115.5 g
(0.35 mol) and 105 g of cardanol (0.3
5 mol) was added, stirring was started, and the temperature in the system was adjusted to 30 to 5
37% by weight formalin aqueous solution while adjusting to 0 ° C 56.
7 g (0.7 mol) was added dropwise over 60 to 120 minutes.
After the dropping is complete, attach a dehydrator and gradually raise the temperature to 100
The reaction was allowed to proceed for 5 hours at ˜150 ° C. while distilling off the water produced in the reaction. Finally, the dehydration reaction was completed under reduced pressure of 110 ° C. and 80 mmHg, and the final product was a brown liquid with a viscosity of 10 ps / 25 ° C. and an amine value of 282 m.
352 g of a Mannich compound (D) of g / KOH was obtained.

Production Example 5 (Production of Mannich Compound) 136.0 g of meta-xylylenediamine was placed in a flask equipped with a heating device, a cooling device, a stirring device, a dropping device and a dehydrating device.
(1.0 mol), terpene phenol 181.5 g
(0.55 mol) and 165 g of cardanol (0.5
5 mol) was added, stirring was started, and the temperature in the system was adjusted to 30 to 5
37% by weight aqueous formalin solution 89.
1 g (1.1 mol) was added dropwise over 60 to 120 minutes.
After the dropping is complete, attach a dehydrator and gradually raise the temperature to 100
The reaction was allowed to proceed for 5 hours at ˜150 ° C. while distilling off the water produced in the reaction. Finally, the dehydration reaction was completed at 110 ° C. under a reduced pressure of 80 mmHg, and the final product was a brown liquid with a viscosity of 10 ps / 25 ° C. and an amine value of 237 m.
498 g of a Mannich compound (E) of g / KOH was obtained.

Production Example 6 (Production of Mannich Compound) The Mannich compounds (A) and (B) obtained in the above Production Examples 1 and 2 were blended at a ratio of 1: 1 to obtain an amine value of 2.
65 mg / KOH Mannich compound (F) [mixture]
Got

Production Example 7 (Production of Epoxy Compound) A 2 liter reactor equipped with a water separator equipped with a thermometer, a stirrer and a cooling tube was charged with Hitanol # 1133 (Hitachi Chemical Co., Ltd .; p-third). Butylphenol-novolak resin, hydroxyl group equivalent 158, average number of nuclides 4) 250 g and Hitanol # 1501 (manufactured by Hitachi Chemical Co., Ltd .; Octylphenol-novolac resin, hydroxyl group equivalent 214, average number of nuclides 4) 250 g, and epichlorohydrin 1440.
After charging g and stirring to make a uniform solution, 268 g of a 48 wt% sodium hydroxide aqueous solution was added dropwise at 60 to 110 ° C. over 2 hours. During this time, the water produced in the system was azeotropically distilled with epichlorohydrin, and the epichlorohydrin was refluxed in the system while being removed outside the system by a water separator. After completion of the dropping, the mixture was aged at 100 to 120 ° C. for 2 hours, and the reaction was terminated when the theoretical amount of water flowed out. To the obtained epichlorohydrin solution of the epoxy compound, 150 g of xylene was added, washed with a large amount of water to remove the generated sodium chloride and excess sodium hydroxide, and then neutralized with a 3 wt% phosphoric acid aqueous solution. Then, epichlorohydrin and xylene were distilled off to obtain an epoxy resin having an epoxy equivalent of 340. To this was further added 460 g of Swazol # 310 (manufactured by Cosmo Matsuyama Co., Ltd .; high boiling paraffinic solvent) to obtain 1150 g of a brown liquid epoxy resin. This resin has a saponifiable chlorine content of 0.3%, an epoxy equivalent of 450, and a solid content of 60% by weight.
Met. In addition to this resin, Adeka polyether P-7
00 (Asahi Denka Kogyo KK; polypropylene glycol, hydroxyl value 155) / Coronate T-80 (Nippon Polyurethane KK; Tolylene diisocyanate) = 1 /
Prepolymer 127g (resin solid content 15%) synthesized in a mole number of 2 was added dropwise over 30 minutes, aged at 90 ° C for 2 hours, further heated to 100 ° C and reacted for 1 hour. Finally, 90 g of Swazol # 310 was added to obtain a yellow liquid epoxy resin composition (α) having a solid content of 60% by weight and an epoxy equivalent of 750.

Production Example 8 (Production of Epoxy Compound) A 2 liter reactor equipped with a water separator equipped with a thermometer, a stirrer and a condenser was charged with 250 g of hitanol # 1133, 250 g of hitanol # 1501 and 1440 g of epichlorohydrin, After stirring to form a uniform solution, 268 g of 48% by weight sodium hydroxide aqueous solution was added to 60%.
Dropwise at ~ 110 ° C over 2 hours. During this time, the water produced in the system was azeotropically distilled with epichlorohydrin, and the epichlorohydrin was refluxed in the system while being removed outside the system by a water separator. After completion of the dropping, the mixture was aged at 100 to 120 ° C. for 2 hours, and the reaction was terminated when the theoretical amount of water flowed out. To the obtained epichlorohydrin solution of the epoxy compound, 150 g of xylene was added, washed with a large amount of water to remove the generated sodium chloride and excess sodium hydroxide, and then neutralized with a 3 wt% phosphoric acid aqueous solution. Then, epichlorohydrin and xylene were distilled off to obtain an epoxy resin having an epoxy equivalent of 340. In addition to this, Swazol # 310 460g
Was added to obtain 1150 g of a brown liquid epoxy resin. This resin has a saponifiable chlorine content of 0.3% and an epoxy equivalent of 45.
0, the solid content was 60% by weight. To this resin, 45.4 g of ADEKA GLYSILOL ED-505 (resin solid content 5%) was added dropwise over 30 minutes, and aged at 90 ° C. for 2 hours,
The temperature was further raised to 100 ° C. and the reaction was carried out for 1 hour. Finally, add 145.2 g of Swazol # 310 to obtain a solid content of 60.
A yellow liquid epoxy resin composition (β) having a weight% of epoxy equivalent of 550 was obtained.

Comparative Production Example 1 (Production of Mannich Compound) 136.0 g of metaxylylenediamine was placed in a flask equipped with a heating device, a cooling device, a stirring device, a dropping device and a dehydrating device.
(1.0 mol) and phenol 84.7 g (0.9 mol) were charged, stirring was started, and the temperature in the system was 30 to 50 ° C.
Adjusting to 37% by weight formalin aqueous solution 72.9g
(0.9 mol) was added dropwise over 60 to 120 minutes. After the dropping, attach a dehydrator and gradually raise the temperature to 100-1
The reaction was allowed to proceed at 50 ° C. for 5 hours while distilling off water produced in the reaction. Finally, the dehydration reaction was completed at 110 ° C. under a reduced pressure of 80 mmHg, and the final product was a brown liquid with a viscosity of 20 pc / 25 ° C. and an amine value of 490 mgKO.
235 g of H / g Mannich compound (I) was obtained.

Comparative Production Example 2 (Production of Mannich Compound) 136.0 g of metaxylylenediamine was placed in a flask equipped with a heating, cooling device, stirring device, dropping device and dehydrating device.
(1.0 mol) and 97.3 g of m-cresol (0.
9 mol) was added, stirring was started, and the temperature in the system was adjusted to 30 to 5
A 37% by weight aqueous formalin solution 72.
9 g (0.9 mol) was added dropwise over 60 to 120 minutes.
After the dropping is complete, attach a dehydrator and gradually raise the temperature to 100
The reaction was allowed to proceed for 5 hours at ˜150 ° C. while distilling off the water produced in the reaction. Finally, the dehydration reaction was completed at 110 ° C. under reduced pressure of 80 mmHg, and the final product was a brown liquid, viscosity 13 pc / 25 ° C., amine value 460 mg.
246 g of Mannich compound (II) with KOH / g was obtained.

Test Examples 1 to 6 and Comparative Test Examples 1 and 2 The Mannich compounds (curing agents) obtained by the above Production Examples and Comparative Production Examples were mixed with mineral spirits at a ratio of 1/1 to improve the solubility. confirmed. The evaluation criteria are as follows. ◯: Dissolved uniformly, clear and no insoluble matter was observed. Δ: A small amount of insoluble matter was observed and it was cloudy. X: A large amount of insoluble matter is seen. The results are shown in [Table 1].

[0042]

[Table 1]

Examples 1 to 9 Mannich compounds [curing agents] obtained by the above production examples, and epoxy compounds (epoxy resin compositions) obtained by the above production examples or commercially available epoxy compounds (epoxy resin compositions) [ The main ingredient] was mixed with active hydrogen equivalent and epoxy equivalent in a ratio of 1: 1 to produce a clear varnish. Then, the obtained clear varnish was applied onto a mild steel plate (SPCC-B) with a film thickness of 7 using an applicator.
The following characteristics were evaluated by coating so as to have a thickness of 0 μ. still,
For 1), 2), 4) and 5), coated steel sheets that had been left for 7 days to dry and cure were used. The results are shown in [Table 2] below.

1) Erichsen: According to JIS K 5400, an Erichsen tester was used, and the conditions were φ20 mm and 8 mm.

2) Impact resistance: According to JIS K 5400, using a DuPont impact tester, 500 g × 50 cm,
The cracked state of the coating film was evaluated under the condition of φ8 mm. ◯: No cracks or cracks are found. Δ: Some cracks and cracks are seen. X: Many cracks and cracks are seen.

3) Solvent resistance: 150 at room temperature after coating
After left for a period of time to dry and cure, one drop of toluene was dropped on the coating film, and a rubbing test with absorbent cotton was performed to confirm the number of times until the undercoat appeared.

4) Amine brushability: After coating, the surface appearance after curing was observed. ○: No abnormality △: Partial, glossy ×: Full surface, glossy XX: Full surface, no gloss

5) Corrosion resistance: The coating film test piece was subjected to SST for 500 hours according to JIS K 5400. Flat part ○: No rust or swelling Δ: Rust, part of swelling ×; Rust, swelling entire surface No cracks or cracks are observed at all.

6) Low temperature curability; 5 ° C./16 after coating
The presence or absence of tacking when left for a certain period of time was evaluated by touch with a finger. ○: Completely dry and no tack △: Slightly tacky ×: Sticky, not cured at all

[0050]

[Table 2]

As is clear from Table 1, when an ordinary Mannich compound obtained from phenol or cresol is used as a curing agent, the solubility in a weak solvent such as mineral spirit is insufficient, Unable to produce uniform clear varnish.

On the other hand, by using the phenolic Mannich compound having a long-chain aliphatic hydrocarbon group or alicyclic hydrocarbon group of the present invention in combination with a weak solvent-soluble epoxy resin, mineral spirit It has excellent solubility in weak solvents, such as impact resistance, solvent resistance, especially when used in combination with a weak solvent-soluble epoxy resin having an aliphatic or alicyclic hydrocarbon group having 4 or more carbon atoms. A coating film having excellent physical properties such as corrosion resistance can be formed (see [Table 2]).

[0053]

The curable epoxy resin composition of the present invention comprises
It is soluble in highly safe, high boiling point, low stimulant solvents, has excellent curability, corrosion resistance, solvent resistance, etc. and is useful for various paints, adhesives, encapsulants, etc.

Continued front page    (72) Inventor Satoshi Suzuki             20 Asahiden, Showa-numa, Iris-cho, Minami-Saitama-gun, Saitama             Chemical Industry Co., Ltd. F-term (reference) 4J036 AB02 AB03 AB17 AB18 AC05                       AC06 AD07 AD08 AD20 AD21                       AF06 AF07 AF08 AF16 AG04                       AG06 AG07 AG13 AJ08 AJ09                       AK03 AK11 AK15 DC05 DC10                       JA01 JA06 JA15

Claims (7)

[Claims] 1. A Mannich compound (a) obtained by reacting (a) a polyamine compound, (b) formaldehyde and (c) a phenol compound having a long-chain aliphatic or alicyclic hydrocarbon group having 10 or more carbon atoms. A curable epoxy resin composition comprising A) and an epoxy compound (B). 2. The curable epoxy resin composition according to claim 1, wherein the polyamine compound (a) is m-xylylenediamine. 3. The Mannich compound (A) is replaced by (a)
With respect to 1 mol of the polyamine compound, (b) formaldehydes 0.3 to 2 mol and (c) phenol compound 0.
The curable epoxy resin composition according to claim 1 or 2, which is obtained by reacting 3 to 2 mol. 4. The curability according to claim 1, wherein 1 to 50 parts by weight of the Mannich compound (A) is mixed with 100 parts by weight of the epoxy compound (B). Epoxy resin composition. 5. The epoxy compound (B) is an epoxy compound having an aliphatic or alicyclic hydrocarbon group having 4 or more carbon atoms, and the epoxy compound (B) according to claim 1. Curable epoxy resin composition. 6. The epoxy compound (B) has 4 carbon atoms which may be crosslinked with a polyisocyanate compound.
The curable epoxy resin composition according to any one of claims 1 to 5, which is a phenol novolac epoxy resin substituted with the above aliphatic or alicyclic hydrocarbon group. 7. The high boiling point paraffinic solvent or at least one 10 to 600 parts by weight of a terpene hydrocarbon oil is contained per 100 parts by weight of the resin component, according to any one of claims 1 to 6. Curable epoxy resin composition.