JP2867823B2 - Aqueous paint composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an aqueous coating composition. More specifically, directly on the metal material or on the base paint,
An aqueous coating composition particularly applied to the inner surface of a metal can that requires high workability and corrosion resistance.

[0002]

2. Description of the Related Art Conventionally, a metal can is usually provided with a thin synthetic resin protective film in order to prevent a metal material such as tinplate, tin-free steel, and aluminum from directly contacting and corroding the contents.

As the inner coating, epoxy coatings such as epoxy / phenol, epoxy / amino and epoxy / acryl are usually used because of their excellent adhesion, corrosion resistance and flavor. However, since the paint is based on a thermosetting resin, it has a drawback of poor workability. For this reason, in cans and applications in which workability is particularly required, a vinyl chloride resin-based organosol paint is used, although it is based on a thermoplastic resin and has a drawback that the extractable components are large and the flavor is inferior.

On the other hand, in recent years, epoxy / acrylic water-based paints have begun to be used in terms of work hygiene, environmental measures, or safety (dangerous substances). As disclosed so far, a water-based paint in which an epoxy resin is esterified with a carboxyl group-containing acrylic resin, neutralized with a base and dispersed in water (JP-B-59-37026), containing a carboxyl group An aqueous paint (Japanese Patent Publication No. 63-17869) in which a polymerizable monomer mixture is grafted onto an epoxy resin using a free radical generator and dispersed in water in the same manner as described above, and an epoxy resin having an acroyl group is converted to acrylic acid Alternatively, an aqueous paint (Japanese Patent Publication No. Sho 62-721) copolymerized with an ethylenic monomer containing methacrylic acid and dispersed in water in the same manner as described above.
No. 3). These are all self-emulsifying epoxy resin-based water-based paints in which the resin itself shows dispersibility,
It did not contain a surfactant for dispersing in water, and was excellent in chemical performance, water resistance and the like.

[0005]

However, the self-emulsifying type epoxy resin-based water-based coating must contain at least 10% or more of an acrylic resin as an emulsifying component. , The corrosion resistance was poor. The problem to be solved by the present invention is a conventional vinyl chloride resin-based organosol paint, and various problems with a self-emulsifying epoxy resin-based water-based paint, particularly workability, an aqueous paint composition excellent in corrosion resistance. To provide.

[0006]

In order to solve the above-mentioned problems, the present invention relates to an epoxy resin (A) and a phenoxy resin (B) modified to have a carboxyl group-containing acrylic polymer portion, and a resol type resin. Provided is an aqueous coating composition in which a phenol resin is aqueous-dispersed using ammonia or an amine.

The epoxy resin used in the present invention includes bisphenol A type epoxy resin and bisphenol F
And epoxy resins having 1.1 to 2.0 epoxy groups in one molecule. Among these epoxy resins, a bisphenol A epoxy resin or a bisphenol F epoxy resin having a number average molecular weight of 1500 to 7000 is preferable. Commercially available products include "Epicoat 1004", "Epicoat 1007", and "Epicoat 1009" manufactured by Shell Chemical Co., Ltd., and "YDF2004" manufactured by Toto Kasei Co., Ltd.
And the like. One or more of the above epoxy resins can be selected and used. Epoxy resin is 5
When the amount is less than 40% by weight, the adhesion to the metal base is inferior, and when it exceeds 40% by weight, the processability is inferior.

The phenoxy resin used in the present invention includes:
It is a resin having the same resin skeleton as the bisphenol A type epoxy resin and having not more than 0.5 epoxy groups in one molecule, and having a very high number average molecular weight of 9000 or more. A commercially available product is Phenoxy PKHH manufactured by Union Carbide Chem. If the phenoxy resin is less than 25% by weight, the processability is poor, and if it exceeds 80% by weight, the adhesion to the metal base is poor, and 25 to 80% by weight is preferable.

In the present invention, the method of modifying the epoxy resin (A) and the phenoxy resin (B) so as to have a carboxyl group-containing acrylic polymer portion is described in the above publications (JP-B-59-37026, JP-B-63-1988). No. 17869, Japanese Patent Publication No. 62-7213) can be applied mutatis mutandis, and specifically, it is preferable to carry out by the following method.

(1) An epoxy resin and a phenoxy resin are
Method of esterifying with a separately prepared carboxyl group-containing acrylic polymer; carboxyl group-containing acrylic polymer is a carboxyl group-containing vinyl monomer such as acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, etc. Vinyl monomers copolymerizable with one or more kinds, for example, styrene monomers such as styrene, vinyltoluene, 2-methylstyrene, t-butylstyrene, chlorostyrene; methyl acrylate;
Ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, isoamyl acrylate, n-hexyl acrylate, n-2 ethylhexyl acrylate, n-acrylate Acrylate monomers such as octyl, decyl acrylate and dodecyl acrylate; methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, Methacrylate monomers such as n-hexyl methacrylate, n-2-ethylhexyl methacrylate, n-octyl methacrylate, decyl methacrylate, dodecyl methacrylate, lauryl methacrylate; Hydroxyl group-containing monomers such as roxyethyl, hydroxypropyl acrylate, hydroxymethyl methacrylate, 2-hydroxyethyl methacrylate and hydroxypropyl methacrylate; N- such as N-methylol (meth) acrylamide and N-butoxymethyl (meth) acrylamide It is obtained by copolymerizing one or more kinds of substituted (meth) acrylic monomers and the like. The carboxyl group-containing acrylic polymer,
The composition ratio and type are not particularly limited, but the carboxyl group-containing vinyl monomer accounts for 5% by weight or more,
Methacrylic acid is used in an amount of up to 80% by weight, and a copolymerizable vinyl monomer is preferably 95% by weight or less, particularly preferably 20 to 70%, and styrene and ethyl acrylate are preferred.
00 is preferred. The esterification reaction is basically based on a reaction between a carboxyl group and an epoxy group and / or a hydroxyl group in the acrylic polymer, and an amine esterification catalyst can be used. Examples of the amine-based esterification catalyst include dimethylethanolamine, dimethylbenzylamine, ethanolamine, diethanolamine, and morpholine.

(2) epoxy resin and phenoxy resin,
A method of grafting a copolymerizable vinyl monomer mixture containing a carboxyl group-containing vinyl monomer using a free radical generator; the vinyl monomer mixture is a carboxyl group-containing vinyl monomer alone or a mixture thereof with another vinyl monomer; Specific examples include those shown in the above (1). The composition ratio and type of the vinyl monomer mixture are not particularly limited, but the content of the carboxyl group-containing vinyl monomer is 5% by weight or more, particularly 30 to 100%.
Methacrylic acid is preferred in an amount of 95% by weight, and styrene and ethyl acrylate are preferred in an amount of 0 to 70% by weight.

(3) epoxy resin and phenoxy resin,
By reacting acrylic acid and / or methacrylic acid
A method of introducing a (meth) acryloyl group and then copolymerizing a vinyl monomer mixture containing acrylic acid and / or methacrylic acid with the group; reaction of an epoxy resin and a phenoxy resin with acrylic acid and / or methacrylic acid The ratio is preferably in the range of 1 / 0.1 to 1 / 1.5 (molar ratio). Specific examples of the vinyl monomer mixture include those shown in the above (1), and the composition ratio and type are not particularly limited.
More than 5% by weight, especially 30-80% by weight of methacrylic acid
95% by weight or less of copolymerizable vinyl monomer, especially 20 to
Styrene at 70% by weight, ethyl acrylate is preferred.

The carboxyl group-containing vinyl monomer and copolymerizable vinyl monomer, epoxy resin and phenoxy resin are preferably in the range of 8/92 to 50/50 (weight ratio), and the epoxy resin and phenoxy resin are less than 50% by weight. In this case, the adhesion to the base material, corrosion resistance, workability, and the like are reduced. On the other hand, if it exceeds 92% by weight, it is difficult to make the aqueous solution aqueous. More preferably, the ratio is 10/90 to 30/70 (weight ratio)%.

An esterified product obtained by the method shown in the above (1), a grafted product obtained by the method shown in the above (2),
The copolymer obtained by the method shown in (3) is mainly composed of an epoxy resin (A) and a phenoxy resin (B), each of which has a carboxyl group-containing acrylic polymer bonded thereto. In some cases, an unbound carboxyl group-containing acrylic polymer coexists.

Examples of the polymerization catalyst for the vinyl monomer used for the modification by the methods shown in the above (1) to (3) and the catalyst for grafting the carboxyl group-containing vinyl monomer to the epoxy resin and the phenoxy resin include, for example, organic peroxides. ,
Persulfates, azobis compounds, and Redox-based catalysts obtained by combining these with a reducing agent can be used. Specifically, benzoyl peroxide, perbutyl octate, t-butyl hydroperoxide, azobisisobutyronitrile, azobisvaleronitrile, 2,2
2′-azobis (2-aminopropane) hydrochloride and the like are exemplified. As the free radical generator as the graft catalyst, benzoyl peroxide is particularly preferred. These can be used generally in a proportion of 0.5 to 20 parts by weight based on 100 parts by weight of the reaction components.

The reaction (1) for obtaining an acrylic polymer,
The esterification reaction shown in (1), the graft reaction shown in (2), the reaction for obtaining the (meth) acryloyl group-containing mixture shown in (3), and the copolymerization reaction of the (meth) acryloyl group-containing mixture, Both are preferably performed in an organic solvent system, and the organic solvent used is preferably a solvent that dissolves monomers such as vinyl monomers and copolymers thereof, an epoxy resin and a phenoxy resin, and is easily mixed with water, For example, alcohol-based, glycol-based, diglycol-based, and acetate-based solvents can be used. Specifically, n-propanol, isopropal, n-butyl alcohol, isobutyl alcohol, n-amyl alcohol, amyl alcohol, methyl amyl alcohol, ethylene glycol, diethylene glycol, 1,3-butylene glycol, ethylene glycol monoethyl ether, Ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, methyl propylene glycol, methyl propylene diglycol, propyl propylene glycol, propyl propylene diglycol, butyl propylene glycol, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, propylene Glycol monomethyl ether ace Over DOO, 3- methoxide butyl acetate, ethylene glycol monobutyl ether acetate, can be mentioned 3-methyl-3-methoxybutyl acetate and the like. Other solvents can be used, but those which can be removed under reduced pressure before or after the production of the aqueous paint are preferred.

The ammonia or amine used in the present invention is an ester obtained by the method shown in the above (1),
It is used for neutralizing carboxyl groups in the grafted product obtained by the method shown in (2) and the copolymer obtained by the method shown in (3), and examples of the amine include trimethylamine, triethylamine, butylamine and the like. Alkylamines, dimethylaminoethanol, diethanolamine, alcoholamines such as aminomethylpropanol, and volatile amines such as morpholine.

The resol-type phenol resin used in the present invention is a resin obtained by condensing an arbitrary phenol component and formaldehyde in the presence of a basic catalyst.
Further, phenol components constituting the resol type phenol resin include o-cresol, p-cresol, p-te
rt-butylphenol, p-ethylphenol, 2,3
Bifunctional phenols such as -xylenol, 2,5-xylenol, p-tert-aminophenol, p-nonylphenol, p-phenylphenol, p-cyclohexylphenol, phenolic acid, m-cresol, m-ethylphenol, 3, Trifunctional phenols such as 5-xylenol and m-methoxyphenol, monofunctional phenols such as 2,4-xylenol and 2,6-xylenol,
Bisphenol A: A single or a combination of two or more of tetrafunctional phenols such as bisphenol B and bisphenol F is used. As the basic catalyst, for example, ammonia, amine, hydroxide of alkaline earth metal, oxide of alkali metal, oxide of alkaline earth metal, or the like can be used. If the resole type phenolic resin is less than 2% by weight, the crosslinking density is low and the corrosion resistance is inferior, and 30% by weight.
On the other hand, if it exceeds, the crosslink density becomes too high and the processability decreases, so 2 to 30% by weight is preferable.

It is possible to add a solvent, a surfactant and an antifoaming agent for improving the coatability, if necessary, to the aqueous coating composition of the present invention. After the formation of the coating film, a wax as a lubricant may be added to the aqueous coating composition of the present invention for the purpose of preventing the coating film from being scratched during processing and transportation.

It is also possible to add an amino resin as a curing agent to the aqueous coating composition of the present invention. However, the addition of a large amount is not preferred because the crosslink density becomes too high and the processability is lowered. Addition of up to 5% by weight is preferred.

As a substrate to be applied, a treated or untreated metal plate such as an aluminum plate, a steel plate, a zinc steel plate, and a tin plate is suitable. Even on the primer,
It may be directly on a metal material. As a coating method, various methods known in this field, for example, roll coater coating, spray coating, dip coating, electrodeposition coating and the like can be applied. Among them, roll coater coating and spray coating are preferable.
The drying and curing conditions are preferably 150 to 230 ° C. for 1 to 30 minutes, or 240 to 300 ° C. for 15 to 60 seconds.

[0022]

The aqueous coating compositions of the present invention are modified products (a1) to (a) in which a carboxyl group-containing acrylic polymer portion is bonded to an epoxy resin (A) and a phenoxy resin (B).
3) and a resin-based phenol resin obtained by aqueous dispersion using ammonia or an amine. The resin is provided with a phenoxy resin skeleton which is a linear high-molecular-weight resin, thereby imparting processability to the resin. By containing a resin, it is possible to improve the adhesion to the base material, and to increase the crosslink density after curing to impart corrosion resistance.

[0023]

Next, the present invention will be described more specifically with reference to examples. In the examples, “parts” and “%” indicate “parts by weight” and “% by weight”, respectively.

Production Example 1 Production of Epoxy Resin and Phenoxy Resin Solution (A) Epicoat 1004 (manufactured by Yuka Shell Epoxy Co., Ltd.) 120.0 parts Phenoxy PKHH (manufactured by Union Cabide Chem.) 480.0 parts Ethylene glycol monoethyl ether 400.0 Part is charged in a four-necked flask with 100 parts under a nitrogen stream.
The mixture was heated to ℃ and completely dissolved to obtain a 60% epoxy resin and phenoxy resin solution (A).

Production Example 2 Production of Epoxy Resin and Phenoxy Resin Solution (B) Epicoat 1004 (manufactured by Yuka Shell Epoxy Co., Ltd.) 240.0 parts Phenoxy PKHH (manufactured by Union Cabide Chem.) 360.0 parts Ethylene glycol monoethyl ether 400.0 In the same manner as in part (1), a 60% epoxy resin and phenoxy resin solution (B) was obtained.

Production Example 3 Production of Carboxyl Group-Containing Acrylic Polymer (C) Styrene 210.0 parts Ethyl acrylate 210.0 parts Methacrylic acid 180.0 parts Benzoyl peroxide 20.0 parts n-butanol 380.0 parts Charged into a four-necked flask and placed under a nitrogen stream. At 100 ° C. over 3 hours, and the mixture was kept at the same temperature for 2 hours to obtain a 60% carboxyl group-containing acrylic polymer solution (C).

Production Example 4 Production of resol-type phenol resin solution (D) Bisphenol A 485.1 parts Formalin 40% n-butanol solution 478.7 parts 25% ammonia water 36.2 parts A 4-necked flask was charged with and charged under a nitrogen stream.
After reacting at 5 ° C. for 5 hours, xylene / n-butanol / cyclohexanone = 1/1/1 was added for dilution, followed by dehydration to obtain a 35% resol phenol resin solution (D).

Preparation Example 5 Preparation of resol type phenol resin solution (E) 417.7 parts of p-cresol 580.1 parts of formalin 40% n-butanol solution 2.2 parts of magnesium hydroxide A reaction was carried out for 2.5 hours in the same manner as in (5). Thereafter, the mixture is neutralized with phosphoric acid, a large amount of water such as xylene / n-butanol / cyclohexanone = 1/1/1 is added thereto, and the mixture is left for 5 hours. 35%
Thus, a resol type phenol resin solution (E) was obtained.

Example 1 Epoxy resin and phenoxy resin solution (A) 271.0 parts Carboxyl group-containing acrylic polymer (C) 83.1 parts Dimethylaminoethanol 15.5 parts Resole-type phenol resin solution (D) 107.2 parts Ion-exchanged water 523.2 parts 4 In a neck flask, was added, and the mixture was added while stirring under a nitrogen stream to substantially equimolar neutralize the carboxyl groups contained therein. Then, the internal temperature was raised to 80 ° C., and the mixture was stirred at this temperature for 30 minutes. After that, the mixture was cooled to room temperature. The reduction rate of the oxirane% was 70%, and the viscosity was increased as compared to before the cooking. After cooking, the mixture was further added with stirring, and further added little by little to obtain an aqueous dispersion having a solid content of 25%.

Examples 2 to 4 In the same manner as in Example 1, the epoxy resin and phenoxy resin solutions (A) and (B) and the carboxyl group-containing acrylic polymer solution (C) were cooked in the composition shown in Table 1. Then, resol-type phenol resin solutions (D) and (E) and ion-exchanged water were added to obtain an aqueous dispersion having a solid content of 25%.

Table 1

[Table 1]

Example 5 Epoxy resin and phenoxy resin solution (A) 270.8 parts n-butanol 70.0 parts Styrene 17.5 parts Ethyl acrylate 17.5 parts Methacrylic acid 15.0 parts Benzoyl peroxide 3.5 parts Resole type phenol resin solution (D) 107.1 parts Dimethyl Aminoethanol 15.5 parts Ion-exchanged water 483.1 parts was charged into a four-necked flask, the internal temperature was raised to 110 ° C, and a mixed solution of was added dropwise over 2 hours while stirring under a nitrogen stream, followed by cooling to room temperature. Was added in small portions to obtain an aqueous dispersion having a solid content of 25%.

Examples 6 to 8

In the same manner as in Example 5, the epoxy resin and phenoxy resin solutions (A), (B)
A vinyl monomer mixture of 35 parts of styrene, 35 parts of ethyl acrylate, 30 parts of methacrylic acid, and 7 parts of benzoyl peroxide was added dropwise thereto, and resol-type phenol resin solutions (D), (E), and dimethylaminoethanol were additionally added. And
Further, ion-exchanged water was added little by little to obtain an aqueous dispersion having a solid content of 25%.

Table 2

[Table 2]

Example 9 (1) 270.8 parts of epoxy resin and phenoxy resin solution (A) (2) 1.5 parts of methacrylic acid (3) 0.03 part of sodium hydroxide (4) 70.0 parts of n-butanol (5) 17.5 parts of styrene ( 6) Ethyl acrylate 17.5 parts (7) Methacrylic acid 13.5 parts (8) Benzoyl peroxide 1.0 part (9) Resole type phenol resin solution (D) 107.1 parts (10) Dimethylaminoethanol 13.9 parts (11) Deionized water 487.2 Part Charge (1) to (3) in a four-necked flask and adjust the internal temperature to 120 to
The temperature was raised to 130 ° C., the reaction was advanced under a nitrogen stream, and when the acid value became 0.5 or less, the mixture was cooled, (4) was added at 90 ° C., and further kept at 90 ° C. while stirring (5 ) To (8) were added dropwise over 2 hours, and the mixture was cooled to room temperature. continue
(9) to (10) were added, and (11) was added little by little with stirring to obtain an aqueous dispersion having a solid content of 25%.

Examples 10 to 12 In the same manner as in Example 9, the epoxy resin and phenoxy resin solutions (A) and (B), methacrylic acid, and sodium hydroxide were charged and reacted in the proportions shown in Table 3. Styrene 35 parts, ethyl acrylate 35 parts, methacrylic acid 27
Part of benzoyl peroxide and 2 parts of vinyl monomer mixture, followed by resole phenol resin solution
(D), (E) and dimethylaminoethanol were added, and ion-exchanged water was added little by little with stirring to obtain an aqueous dispersion having a solid content of 25%.

Table 3

[Table 3]

Comparative Production Example 1 Production of Epoxy Resin Solution (F) Epicoat 1007 (manufactured by Yuka Shell Epoxy Co., Ltd.) 600.0 parts Ethylene glycol monoethyl ether 400.0 parts In a four-necked flask, was charged and placed under a nitrogen stream. 100
℃, completely dissolved and 60% epoxy resin solution (F)
I got

Comparative Production Example 2 Production of Epoxy Resin Solution (G) Epicoat 1009 (manufactured by Yuka Shell Epoxy Co., Ltd.) 600.0 parts Ethylene glycol monoethyl ether 400.0 parts ~ was charged into a four-necked flask and placed under a nitrogen stream. 100
℃, completely dissolved and 60% epoxy resin solution (G)
I got

Comparative Example 1 An aqueous dispersion having a solid content of 25% was prepared in the same manner as in Example 1 except that the epoxy resin and phenoxy resin solution (A) in Example 1 was changed to the epoxy resin solution (F). I got

Comparative Example 2 An aqueous dispersion having a solid content of 25% was prepared in the same manner as in Example 5 except that the epoxy resin and phenoxy resin solution (A) in Example 5 was changed to the epoxy resin solution (G). I got

Comparative Example 3 An aqueous dispersion having a solid content of 25% was prepared in the same manner as in Example 9 except that the epoxy resin and phenoxy resin solution (A) in Example 9 was changed to the epoxy resin solution (G). I got

Comparative Example 4 Resol type phenol resin solution in Example 9 above
Except for removing (D), all operations were performed in the same manner as in Example 9 to prepare ion-exchanged water to obtain an aqueous dispersion having a solid content of 25%.

Comparative Examples 5 to 8 The same procedures as in Example 1 were carried out except that the composition in Example 1 was changed to the composition shown in Table 4, and the solid content was 25%.
Was obtained.

Table 4

[Table 4]

[0047]

[Preparation of paint] The organic solvent contained in the aqueous dispersions obtained in the above Examples and Comparative Examples was removed under reduced pressure so that the content was 15% in the paint at a solid content of 25%. Adjusted.

Performance Test As a result of the storage stability test of the aqueous coating compositions obtained in Examples 1 to 12 and Comparative Examples 1 to 10, the aqueous coating compositions were coated on a tin plate with a bar coater so as to have a thickness of 10 μm, Test panels were prepared by baking and drying for 5 minutes, and the results of evaluating various physical properties are shown in Tables 5 and 6.

The various test methods in Table 5 are as follows. (1) Storage stability of the paint: The paint was stored in a thermostat at 50 ° C., and the appearance and properties were periodically evaluated. Good storage stability ・ ・ ・ ・ ○ Abnormalities such as gelation, sedimentation and separation occurred during storage ・ ・ ・ ・ ×

(2) Adhesion: Eleven cuts each in the vertical and horizontal directions are cut into a width of about 1.5 mm using a knife on the coating surface. The number of unstripped portions of the gobang when the cellophane adhesive tape having a width of 24 mm is closely adhered and strongly peeled is represented by a molecule.

(3) Water resistance: Treated in water at 125 ° C. for 40 minutes to determine the surface condition of the coating film.

(4) Workability: Using a special goby fold-up type ponpon impact tester, place the sample folded in two underneath, drop a 1 kg iron weight with a flat contact surface from a height of 50 cm. The length of the crack in the coating film at the bent portion generated at the time was measured. 0 to 10 mm ··· ○ mark 10 to 20 mm ··· △ mark 20 mm or more ··· × mark

[0053]

(5) Corrosion resistance: using a knife on the coating surface
The test piece with the notch was placed in a 1% saline solution for 125 minutes.
The treatment is performed at 40 ° C. for 40 minutes, and the degree of corrosion in the vicinity of the X mark is determined. No abnormality ・ ・ ・ ・ ○ mark Slightly corroded ・ ・ ・ ・ △ mark Significantly corroded ・ ・ ・ ・ ×

Table 5

[Table 5]

Table 6

[Table 6]

FIG. 6

────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C09D 171/10 C09D 171/10 (56) References JP-A-63-43966 (JP, A) JP-A-63-69871 (JP) (A) JP-A-3-168256 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) C09D 163/00-163/10 C09D 171/10 C09D 133/06-133/12 C09D 161/06-161/14 C09D 151/08 C09D 5/00

Claims (3)

(57) [Claims] 1. An epoxy resin (A) and a phenoxy resin
Carboxyl group-containing acrylic copolymerization of the mixture with (B)
Modified product (a1) obtained by esterification with isomer (C1)
Sol-type phenolic resin (D)
An aqueous coating composition that is aqueously dispersed using a min, When the solid content of the aqueous coating composition is 100% by weight
To Epoxy resin (A) 5-40% by weight Phenoxy resin (B) 25 to 80% by weight Carboxyl group-containing acrylic copolymer (C1) 7 to 30% by weight Resol type phenol resin (D) 2-30% by weight An aqueous coating composition, characterized in that: 2. An epoxy resin (A) and a phenoxy resin
The mixture with (B) is added to the mixture using a free radical generator.
Copolymerizable vinyl containing vinyl monomer containing ruboxyl group
Modified product obtained by grafting a benzyl monomer mixture (a
2) and resol-type phenolic resin (D)
Aqueous coating composition aqueous-dispersed using a or amine
And When the solid content of the aqueous coating composition is 100% by weight
To Epoxy resin (A) 5-40% by weight Phenoxy resin (B) 25 to 80% by weight Copolymerization containing a carboxyl group-containing vinyl monomer subjected to the graft reaction Possible vinyl monomer mixture (C2) 7-30% by weight Resol type phenol resin (D) 2-30% by weight An aqueous coating composition, characterized in that: 3. An epoxy resin (A) and a phenoxy resin
Acrylic acid and / or methacrylic acid are added to the mixture with (B).
(Meth) acryloyl group-containing mixture obtained by reacting an acid
With acrylic acid and / or methacrylic acid as essential components
Copolymer (a) copolymerized with a vinyl monomer
3) and resol-type phenolic resin (D)
Aqueous coating composition aqueous-dispersed using a or amine
And When the solid content of the aqueous coating composition is 100% by weight
To Epoxy resin (A) 5-40% by weight Phenoxy resin (B) 25 to 80% by weight It is subjected to a reaction with the mixture of the epoxy resin (A) and the phenoxy resin (B). Acrylic acid and / or methacrylic acid, and the above (meth) acryloyl group-containing mixture Acrylic acid and / or methacrylic acid provided for copolymerization with the compound as an essential component Vinyl monomer (C3) containing 7-30% by weight Resol type phenol resin (D) 2-30% by weight An aqueous coating composition, characterized in that: