JPH09176285A - Epoxy resin composition - Google Patents

Abstract

(57) Abstract: [PROBLEMS] To provide an epoxy resin composition capable of forming a film having good adhesion and anticorrosion property even when exposed to severe conditions for a long time. SOLUTION: The epoxy resin composition of the present invention comprises (A)
A reaction product of a phosphoric acid and a monoglycidyl ether compound represented by the following general formula (I) represented by the general formula (I) or a monoglycidyl ester compound represented by the general formula (II), and P
It is composed of a phosphate compound having at least one —OH bond and a polyglycidyl compound having at least one epoxy group in the molecule (B). Embedded image

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an epoxy resin composition, and more specifically, to a reaction product of a phosphoric acid and a glycidyl compound, which comprises a phosphoric acid ester compound having at least one P--OH bond and a polyglycidyl compound. In particular, the present invention relates to an epoxy resin composition used as a paint, an adhesive or the like.

[0002]

BACKGROUND OF THE INVENTION An epoxy resin composition comprising an epoxy resin and a curing agent has many excellent properties such as adhesion to various substrates, heat resistance, chemical resistance, electrical properties, mechanical properties, etc. It is used in a wide range of industrial fields, especially in the field of paints and adhesives.

When used in these applications, it is used as a solvent type using various organic solvents, a solventless type not using an organic solvent, or an aqueous type in which an epoxy resin composition is dispersed in water. When these epoxy resin compositions are applied to a material in which rust has already occurred, or a material used in a wet atmosphere where rust is likely to occur, the anticorrosion performance is insufficient. In particular, when applied to steel plates that have already rusted (rust-faced steel plates), the corrosion resistance is not sufficient at all and adhesion failure occurs, so it is complicated to remove rust in advance. It was necessary to have a good surface treatment. Further, even if such a base treatment is performed, when used in an environment where rust is likely to occur, such as in a wet atmosphere, it is not possible to eliminate the drawback that the anticorrosion performance and the adhesion are deteriorated. .

For this reason, it has been attempted to maintain the anticorrosion property even when applied to a rust-faced steel sheet by giving an epoxy resin a functional group having a chelate-forming ability. JP-A-143620 proposes a reaction product of a specific diphosphonic acid and an epoxy resin, and JP-A-58-63758 discloses a coating composition containing an epoxy resin treated with a phosphoric acid compound and a curing agent for the epoxy resin. Things have been proposed.

By using such an epoxy resin treated with a phosphoric acid compound, the initial adhesion and anticorrosion property are improved to some extent, but the effect when exposed for a long time under severe conditions is insufficient. , Was not satisfactory in practice.

Accordingly, it is an object of the present invention to provide an epoxy resin composition which can form a film having good adhesion and anticorrosion properties even when exposed to severe conditions for a long time.

[0007]

Means for Solving the Problems As a result of intensive investigations, the present inventors have found that a novel phosphoric acid ester compound containing a P—OH group and an epoxy group are reaction products of phosphoric acid and a specific glycidyl compound. It has been found that an epoxy resin composition comprising a polyglycidyl compound having: can achieve the above object.

The present invention has been made on the basis of the above findings, and comprises (A) a phosphoric acid compound and a monoglycidyl ether compound represented by the following general formula (I) represented by the following [chemical formula 2] (the same as the above-mentioned [chemical formula 1]). Alternatively, a phosphoric acid ester compound having at least one P-OH bond, which is a reaction product with a monoglycidyl ester compound represented by the general formula (II), and (B) at least one epoxy group in the molecule. An epoxy resin composition comprising a polyglycidyl compound having

[0009]

Embedded image

The present invention also provides a curable composition containing the above-mentioned epoxy resin composition and a curing agent for epoxy resin.

[0011]

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

The phosphoric acid ester compound which is the component (A) used in the present invention is a monoglycidyl ether compound represented by the phosphoric acid and the above general formula (I) or a monoglycidyl ether compound represented by the above general formula (II). It is a reaction product with a glycidyl ester compound and has at least one P-OH bond.

Here, examples of the phosphoric acid include:
Examples thereof include orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid, phosphorous acid, polyphosphoric acid, phosphonic acid, methanephosphonic acid, benzenephosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid and phosphinic acid.

In the above general formulas (I) and (II), examples of the alkyl group represented by R and R'include, for example, methyl, ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl, nonyl and decyl. , Straight chain or branched alkyl groups such as undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, heneicosyl, behenyl, etc., and the alkenyl group includes 1 to 3 in the above alkyl groups. Examples of the aryl group include those having an unsaturated bond.
Examples thereof include a phenyl group and a naphthyl group, and these aryl groups may be substituted with 1 to 3 of the above alkyl groups, and these substituents may be taken together to form a ring.

The monoglycidyl ether compound represented by the above general formula (I) and the monoglycidyl ester compound represented by the above general formula (II) are usually prepared from epichlorohydrin and alcohols, phenols or organic carboxylic acids. It can be easily obtained by the method.

Examples of the monoglycidyl ether compound represented by the above general formula (I) include methyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, sec-butylphenyl glycidyl ether, 2-methyloctyl glycidyl ether, Octadecyl glycidyl ether, phenyl glycidyl ether, tolyl glycidyl ether, octyl phenyl glycidyl ether, etc. are mentioned.

Examples of the monoglycidyl ester compound represented by the above general formula (II) include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid and 2-ethylhexylic acid. , Neodecanoic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, palmitic acid, isostearic acid, stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, acrylic acid, methacrylic acid, crotonic acid, elaidin Acid, oleic acid, linoleic acid, linoleic acid, benzoic acid, p-tert-butylbenzoic acid, toluic acid, dimethylbenzoic acid, ethylbenzoic acid,
Examples thereof include glycidyl ester compounds of monovalent carboxylic acids such as cuminic acid and n-propylbenzoic acid.

In obtaining the phosphoric acid ester compound which is the component (A), the phosphoric acid and the monoglycidyl ether compound represented by the above general formula (I) or the monoglycidyl ether compound represented by the above general formula (II) are used. What is a glycidyl ester compound?
The epoxy group (epoxy equivalent) of the compound of the general formula (I) or (II) is preferably 0.1 to 0.9 equivalents, and more preferably 0.1 to 1 equivalent of P-OH group of the phosphoric acid. It is used in an amount of 3 to 0.8 equivalent. Here, when the epoxy group is less than 0.1 equivalent, there is a possibility that excess phosphoric acid and a polyglycidyl compound which is the component (B) described below may react to cause gelation. If it exceeds the limit, denaturation becomes difficult, which is not preferable.

Production examples of the phosphoric acid ester compound which is the component (A) used in the present invention are shown below, but the production method is not limited to these. The acid value is defined as the number of mg of potassium hydroxide required to neutralize the P-OH group in 1 g of the sample.

Production Example 1 85 parts by weight (hereinafter simply referred to as%) of phosphoric acid (115 parts by weight) was added with butyl glycidyl ether (140 parts by weight) to obtain 50 parts by weight.
The reaction was carried out at -60 ° C for 3 hours to obtain a phosphoric acid ester compound (A-1) having an acid value of 440.

Production Example 2 280 parts by weight of butyl glycidyl ether was added to 115 parts by weight of 85% phosphoric acid, and the mixture was reacted at 50-60 ° C. for 3 hours,
A phosphoric acid ester compound (A-2) having an acid value of 142 was obtained.

Production Example 3 300 parts by weight of phenylglycidyl ether was added to 178 parts by weight of pyrophosphoric acid, and the mixture was reacted at 50 to 60 ° C. for 3 hours,
A phosphoric acid ester compound (A-3) having an acid value of 353 was obtained.

Production Example 4 (Production of terpene monophenyl monoglycidyl ether) YP-90LL (Yasuhara Chemical Co., Ltd. terpene mono) was placed in a 2 L reactor equipped with a thermometer, a stirrer and a water separator equipped with a cooling tube. Phenol 90% -containing compound; average molecular weight 266, hydroxyl equivalent 300) 486 g and epichlorohydrin 649 g were charged and stirred to make a uniform solution, and then 48% sodium hydroxide solution 150
g was added dropwise at 60 to 110 ° C. over 2 hours. During this time,
The water generated in the system was azeotropically distilled with epichlorohydrin and removed to the outside of the system with a water separator, and epichlorohydrin was refluxed into the system. After the dropping, it was aged at 100 to 120 ° C. for 2 hours to obtain an epichlorohydrin solution of an epoxy compound. The end point of the reaction was the time when the theoretical amount of water was distilled off.

To the obtained epichlorohydrin solution of the epoxy compound, 800 g of toluene 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% aqueous phosphoric acid solution. Then, epichlorohydrin and toluene were distilled off under reduced pressure to obtain 478 g of a pale yellow transparent liquid epoxy compound having an epoxy equivalent of 430. The epoxy compound had a saponifiable chlorine% of 0.01% and a viscosity of 900 cp / 25 ° C.

The refractive index of the epoxy compound was measured and found to be 1.538. As a result of infrared absorption spectrum analysis, the following characteristic absorption was obtained. 2920 cm ^-1 ,
^{1510cm -1, 1450cm -1, 1360cm -1} , 1
250cm ^-1, 830cm ^-1, 750cm ^-1

(Production of Phosphoric Acid Ester Compound) To 115 parts by weight of 85% phosphoric acid, 350 parts by weight of the epoxy compound (terpene monophenyl monoglycidyl ether) obtained above was added, and the mixture was reacted at 50-60 ° C. for 3 hours, Acid value 24
The phosphoric acid ester compound (A-4) of 1 was obtained.

Preparation Example 5 To 115 parts by weight of 85% phosphoric acid, 142 parts by weight of methacrylic acid monoglycidyl ester was added and reacted at 50 to 60 ° C. for 3 hours to give an organic phosphate ester having an acid value of 437 (A-5).
I got

As the polyglycidyl compound having at least one epoxy group in the molecule, which is the component (B) used in the present invention, the structure of the polyglycidyl compound may be any one as long as it is usually used for preparing an epoxy resin composition. In particular, the polyglycidyl ether compound, the polyglycidyl ester compound and the polyglycidyl ester compound having an average of more than one glycidyl ether group, glycidyl ester group and glycidyl group such as glycidylamino group in the molecule are not particularly limited. Glydylamino compounds are preferred.

The polyglycidyl ether compound is obtained by converting a phenolic or alcoholic hydroxyl group into a polyglycidyl ether by a known method, and examples thereof include resorcinol, hydroquinone, pyrocatechol, phloroglucinol and dihydroxynaphthalene. , Biphenol, methylenebisphenol (bisphenol F), methylenebis (orthocresol), ethylidene bisphenol, isopropylidene bisphenol (bisphenol A), isopropylidene bis (orthocresol), tetrabromobisphenol A, bis (hydroxyphenyl) phenylmethane, bis ( Hydroxyphenyl) cyclohexylmethane, cyclohexylidene bisphenol, thiobisphenol, sulfobisphenol (biphenyl Phenol S), oxy bisphenol, 1,3-bis (4-hydroxycumyl) benzene, 1,4-bis (4-hydroxycumyl) benzene,
Phenol-polyglycidyl ethers of mononuclear or polynuclear polyphenols such as formaldehyde condensates and ethylene glycol, propylene glycol, butylene glycol, hexanediol, polyglycol, thiodiglycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, Bisphenol A
-Polyglycidyl ethers of polyhydric alcohols such as ethylene oxide adducts.

Examples of the polyglycidyl ester compound include maleic acid, fumaric acid, itaconic acid, succinic acid, glutaric acid, suberic acid, adipic acid,
Azelaic acid, sebacic acid, dimer acid, trimer acid,
Polyesters of aliphatic, aromatic or alicyclic polybasic acids such as phthalic acid, isophthalic acid, terephthalic acid, trimellitic acid, trimesic acid, pyromellitic acid, tetrahydrophthalic acid, hexahydrophthalic acid, endomethylenetetrahydrophthalic acid Examples thereof include homopolymers or copolymers of glycidyl esters and polyglycidyl methacrylate.

Examples of the polyglycidylamino compound include N, N-diglycidylaniline and bis (4- (N-methyl-N-glycidylamino) phenyl) methane.

Other polyglycidyl compounds include epoxidized soybean oil, epoxidized linseed oil, epoxidized safflower oil, epoxidized tall oil and other epoxidized natural fats and oils, vinylcyclohexene diepoxide, dicyclopentadiene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-6-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate, bis (3,4-epoxy-) 6
-Methylcyclohexylmethyl) epoxidized cyclic olefin compound such as adipate, epoxidized polybutadiene, epoxidized conjugated diene polymer such as epoxidized styrene-butadiene copolymer, and heterocyclic compound such as triglycidyl isocyanurate You can also

In the present invention, the amount of the phosphoric acid ester compound which is the component (A) is not particularly limited as long as the epoxy group remains in the adduct, but it is usually the component (B). The amount of the P-OH group of the phosphoric acid ester compound is preferably 0.01 to 0.8 equivalents, and more preferably 0.03 to 0.5 equivalents, relative to 1 equivalent of the epoxy groups of the polyglycidyl compound. When the P-OH group of the phosphoric acid ester compound is less than 0.01 equivalent, the effect of phosphoric acid addition is difficult to develop, and when it exceeds 0.8 equivalent, the residual epoxy groups are small, Curability may decrease.

In the present invention, the phosphoric acid ester compound as the component (A) may be modified by partially replacing it with another phosphoric acid ester compound or salt. Examples of the other phosphoric acid ester compounds include orthophosphoric acid, metaphosphoric acid, pyrophosphoric acid,
Phosphorous acid, polyphosphoric acid, phosphonic acid, methanephosphonic acid, benzenephosphonic acid, 1-hydroxyethane-1,
Examples thereof include alkyl, alkenyl or substituted alkyl partial esters of phosphoric acids such as 1-diphosphonic acid and phosphinic acid. Here, as the alkyl group, methyl, ethyl, propyl, butyl, hexyl, octyl,
Examples include groups such as isooctyl, 2-ethylhexyl, decyl, dodecyl, tetradecyl, octadecyl,
The alkenyl group is preferably an alkenyl group having 1 to 30 carbon atoms such as allyl, octenyl, decenyl and octadecenyl, and the substituted alkyl group is 2
-Hydroxyalkyl groups such as hydroxyethyl, 2-hydroxypropyl, 2-hydroxybutyl, 2-hydroxy-2-phenylethyl; 2- (3-methoxy-2-
Hydroxypropoxy) ethyl, 2- (3-butoxy-
2-hydroxypropoxy) ethyl, 2- (3-phenoxy-2-hydroxypropoxy) ethyl, 2- (3-
Preferred are those having a hydroxy group and / or an ether bond such as alkoxy or aryloxyhydroxyalkoxyalkyl groups such as toloxy-2-hydroxypropoxy) ethyl, and the above salts include
Examples thereof include salts of the above acids such as potassium, lithium, sodium, calcium, barium and zinc.

Further, in the present invention, the fact that the phosphoric acid ester compound which is the component (A) and the polyglycidyl compound which is the component (B) react with each other makes the adhesion and the anticorrosion property further excellent. It is preferable because a coating film can be obtained.

Further, the epoxy resin composition of the present invention can be used together with a curing agent for epoxy resin to be cured.

Next, the curable composition of the present invention will be described in detail. The curable composition of the present invention comprises the above-mentioned epoxy resin composition of the present invention and an epoxy resin curing agent.

Examples of the epoxy resin curing agent include ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, 1,4-butylenediamine, hexamethylenediamine, 2,4,4-. Aliphatic polyamines such as trimethylhexamethylenediamine, diethylenetriamine, dipropylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine, dimethylaminopropylamine, diethylaminopropylamine, menthenediamine, 1,3-bis (amino) Methyl) cyclohexane, isophoronediamine, N-3-aminopropylcyclohexylamine, 1,4-diaminocyclohexane, 2,4
Alicyclic groups such as diaminocyclohexane, bis (aminocyclohexyl) methane, 1,3-bis (aminocyclohexylpropane), bis (3-methyl-4-aminocyclohexyl) methane, 1,4-bis (ethylamino) cyclohexane Polyamines, m-xylylenediamine, p-xylylenediamine, 4- (1-aminoethyl) aniline, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, bis (3
-Ethyl-4-amino-5-methylphenyl) methane,
Aromatic polyamines such as 1,4-bis (2- (3,5-dimethyl-4-aminophenyl) propyl) benzene,
Polyamine curing agents such as N-aminoethylpiperazine, heterocyclic polyamines such as 3,9-bis (3-aminopropyl) -2,4,8,10-tetraoxaspiro [5.5] undecane, and the like, Polyamine curing agents obtained by reacting polyamines with dicarboxylic acids such as dimer acid by a conventional method, or epoxy addition modified polyamine curing agents obtained by adding an epoxy resin to these polyamines or acrylonitrile was added. Examples thereof include Michael addition-modified polyamine curing agents, and latent curing agents such as dicyandiamide, acid anhydrides and imidazoles can also be used.

It is also possible to add a solvent to the above-mentioned curing agent for epoxy resin for the purpose of lowering the viscosity, and to add a surfactant according to the purpose of use and disperse in water, A water-based curing agent can also be used.

The above curing agent for epoxy resin is used in such a range that the active hydrogen equivalent is preferably 0.8 to 1.3 equivalents relative to 1 equivalent of the epoxy group in the epoxy resin composition. If the active hydrogen equivalent is less than 0.8 equivalent, uncured epoxy resin may remain, and if it exceeds 1.3 equivalent, active hydrogen remains, so that the water resistance of the cured product may decrease.

The content of the epoxy resin composition in the curable composition of the present invention is optional according to various uses and is not particularly limited.

The curable composition of the present invention can be prepared by a suitable method such as brush coating, roller, spray, spatula coating, press coating, doctor blade coating, electrostatic coating, electrodeposition coating,
It is used as a coating material, sealant, filler, adhesive, etc. by applying it to a substrate by a method such as dip coating. Especially, since it is excellent in corrosion resistance and adhesion to the substrate, for example, solvent type Or as a solvent-free type for use in heavy-duty anticorrosion paints for anticorrosion of onshore and offshore structures, or as an aqueous type for onshore structures, especially for coating materials such as anticorrosion paints in closed places or condominiums where handling of hazardous materials is a problem. Are suitable.

The epoxy resin composition of the present invention and the curable composition of the present invention include glass fiber, cellulose,
Silica sand, cement, kaolin, clay, aluminum hydroxide, bentonite, talc, silica, fine powder silica,
Titanium dioxide, carbon black, graphite, iron oxide, fillers such as bituminous substances, pigments, thickeners, thixotropic agents, dispersants, flame retardants, defoaming agents, etc.
Further, a concomitant agent such as xylene resin and petroleum resin may be used.

[0044]

EXAMPLES The present invention will be described in more detail below with reference to examples (preparation examples and use examples of epoxy resin compositions).
However, the invention is not limited by these examples. In the following examples, the epoxy equivalent represents the molecular weight of the sample per epoxy group, the hydroxyl group equivalent represents the molecular weight of the sample per hydroxyl group, and the active hydrogen equivalent is the hydrogen atom of amine. It represents the molecular weight of each sample, and when a solvent is used, it represents the apparent molecular weight including the solvent.

Example 1 Adeka Resin EP-4100 (manufactured by Asahi Denka Co., Ltd .: bisphenol A type epoxy resin, epoxy equivalent 190)
190 parts by weight, 20 parts by weight of ADEKA GLYSILOL ED-503 (Asahi Denka Kogyo KK: aliphatic diglycidyl ether, epoxy equivalent 165) and 10 parts by weight of a phosphoric acid ester compound (A-1) are mixed, and 80 The reaction is carried out at 5 ° C. for 5 hours to obtain an epoxy resin composition (E-1) (epoxy equivalent 21
0, epoxy / P-OH equivalent ratio 1 / 0.07) was obtained.

Example 2 190 parts by weight of ADEKA RESIN EP-4100, 20 parts by weight of ADEKA GLYSILOL ED-503 and 5 parts by weight of the phosphoric acid ester compound (A-1) were mixed and reacted at 80 ° C. for 5 hours to obtain an epoxy resin. Composition (E-2) (epoxy equivalent 198, epoxy / P-OH equivalent ratio 1 / 0.04)
I got

Example 3 190 parts by weight of ADEKA RESIN EP-4100, 20 parts by weight of ADEKA GLYSILOL ED-503 and 20 parts by weight of the phosphoric acid ester compound (A-1) were mixed, and the mixture was mixed at 5 ° C. at 80 ° C.
Epoxy resin composition (E-3) (epoxy equivalent 235, epoxy / P-OH equivalent ratio 1 / 0.1
4) was obtained.

Example 4 190 parts by weight of ADEKA RESIN EP-4100, 58 parts by weight of bisphenol A and 1 part by weight of dimethylbenzylamine were mixed and reacted at 150 ° C. for 8 hours to obtain an epoxy resin having an epoxy equivalent of 500. Further xylene 115
20 parts by weight of a phosphoric acid ester compound (A-2) are added, and the mixture is further reacted at 80 ° C. for 5 hours to obtain an epoxy resin composition (E-4) (epoxy equivalent: 640, epoxy /
P-OH equivalent ratio 1 / 0.11) was obtained.

Example 5 Adeka Resin EP-4900 (manufactured by Asahi Denka Co., Ltd .: bisphenol F type epoxy resin, epoxy equivalent 170)
170 parts by weight, 60 parts by weight of the phosphoric acid ester compound (A-3) and 100 parts by weight of xylene were mixed, and the mixture was mixed at 80 ° C. for 5 minutes.
Epoxy resin composition (E-5) (epoxy equivalent 370, epoxy / P-OH equivalent ratio 1 / 0.3
8) was obtained.

Example 6 ADEKA RESIN EP-5100 (Asahi Denka Kogyo KK: Bisphenol A type epoxy resin, epoxy equivalent 475)
475 parts by weight, 12 parts by weight of the phosphoric acid ester compound (A-4) and 209 parts by weight of xylene are mixed, and the mixture is mixed at 80 ° C. for 5 times.
Epoxy resin composition (E-6) (epoxy equivalent 515, epoxy / P-OH equivalent ratio 1 / 0.0
5) was obtained.

Example 7 190 parts by weight of ADEKA RESIN EP-4100, 20 parts by weight of ADEKA GLYSILOL ED-503 and 10 parts by weight of a phosphoric acid ester compound (A-5) were mixed, and the mixture was mixed at 5 ° C. at 80 ° C.
Epoxy resin composition (E-7) (epoxy equivalent 211, epoxy / P-OH equivalent ratio 1 / 0.0
7) was obtained.

Example 8 190 parts by weight of ADEKA RESIN EP-4100, YP-9
190 parts by weight of 0 L (manufactured by Yasuhara Chemical Co., Ltd .: terpene phenol resin, hydroxyl equivalent 310) and 2 parts by weight of triphenylphosphine were mixed and reacted at 150 ° C. for 8 hours to obtain an epoxy resin having an epoxy equivalent of 980. Further, 167 parts by weight of xylene and 10 parts by weight of the phosphoric acid ester compound (A-1) were added and reacted at 80 ° C. for 5 hours to obtain an epoxy resin composition (E-8) (epoxy equivalent: 12
60, epoxy / P-OH equivalent ratio 1 / 0.25) was obtained.

Comparative Example 1 190 parts by weight of ADEKA RESIN EP-4100, 20 parts by weight of ADEKA GLYSILOL ED-503 and 11 parts by weight of monoethyl phosphate were mixed and reacted at 80 ° C. for 5 hours.
Epoxy resin composition (ratio -1) (epoxy equivalent 216,
Epoxy / P-OH equivalent ratio 1 / 0.07) was obtained.

Comparative Example 2 190 parts by weight of ADEKA RESIN EP-4100, 58 parts by weight of bisphenol A and 1 part by weight of dimethylbenzylamine were mixed and reacted at 150 ° C. for 8 hours to obtain an epoxy resin having an epoxy equivalent of 500. Further xylene 105
An unmodified epoxy resin composition (ratio -2) is added by weight.
I got

The epoxy resin compositions obtained in Examples 1 to 8 and Comparative Examples 1 and 2 were kneaded for 5 hours with a ball mill in the following composition to obtain white paints.

(Compounding) Parts by Weight Epoxy Resin Composition 100 Titanium Dioxide 20 Zinc Phosphate 40 Talc 25 Calcium Carbonate 25 Xylene 20 Isopropanol 20

To the obtained white paint, ADEKA HARDNER EH-340 (manufactured by Asahi Denka Kogyo Co., Ltd .: modified polyamidoamine, active hydrogen equivalent 81) was used as a curing agent, and the epoxy compound of the epoxy compound / hardener active hydrogen was 1 / A coating composition was prepared by blending in the amounts shown in the following [Table 1] so that the ratio of 1 equivalent was obtained.

The resulting coating composition was exposed to a rust-faced steel plate (outdoor for 1 year, and floating rust was removed with a wire brush.
(Seed Keren steel plate) with a film thickness of 120 to 150 μm, left at 25 ° C. for 7 days, and dried and cured to form a coating film. This coating is subjected to a performance test on the following items,
Each performance was evaluated.

(Adhesion) The peel strength was measured using an adhesion tester.

(Corrosion resistance) A salt spray test was conducted according to JIS Z-2371. The state of the coating film after 500 hours and 1000 hours of salt spraying was observed and evaluated according to the following evaluation criteria. ○: No abnormality. Δ: Some blistering occurred. ×: Blisters were generated on the entire surface.

(Secondary Adhesion) An adhesiveness test was conducted on the sample after 1000 hours of salt spray test.

The above results are shown in the following [Table 1].

[0063]

[Table 1]

From the above results, the following is clear. When the epoxy resin composition is cured using a curing agent for epoxy resin to form a film, when an epoxy resin composition which is not modified with phosphoric acid (Comparative Example 2) is used, adhesion and corrosion resistance are improved. Inferior in coating properties such as properties.
Further, by using an epoxy resin composition (Comparative Example 1) modified with a phosphate ester compound other than the phosphate ester compound which is the component (A) according to the present invention, these coating film performances are improved. However, the effect of improving the anticorrosive property is still insufficient.

On the other hand, by using the epoxy resin compositions (Examples 1 to 8) modified with the phosphoric acid ester compound which is the component (A) according to the present invention, adhesion, corrosion resistance and the like are improved. A coating film having remarkably excellent coating film performance can be provided.

[0066]

INDUSTRIAL APPLICABILITY The epoxy resin composition of the present invention, when used together with a curing agent for an epoxy resin, can provide a coating film excellent in adhesion and corrosion resistance, and is particularly suitable for use as a coating material. Is something that can be done.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenji Furusho 5-2-13 Shirahata, Urawa-shi, Saitama Asahi Denka Kogyo Co., Ltd.

Claims (4)

[Claims] 1. A reaction product of (A) a phosphoric acid and a monoglycidyl ether compound represented by the following general formula (I) represented by the general formula (I) or a monoglycidyl ester compound represented by the general formula (II). An epoxy resin composition comprising a phosphate ester compound having at least one P-OH bond, and a polyglycidyl compound having at least one epoxy group in the molecule (B). Embedded image 2. The amount of the phosphoric acid ester compound as the component (A) to be used is 1 equivalent of the epoxy group of the polyglycidyl compound as the component (B) to the P—OH group of the phosphoric acid ester compound. The epoxy resin composition according to claim 1, wherein the amount is 0.01 to 0.8 equivalent. 3. The epoxy resin composition according to claim 1, wherein the phosphoric acid ester compound as the component (A) and the polyglycidyl compound as the component (B) react with each other. 4. A curable composition comprising the epoxy resin composition according to claim 1, 2 or 3 and a curing agent for an epoxy resin.