JPH0827416A - Aqueous dispersion composition - Google Patents

Abstract

PURPOSE:To obtain an aqueous dispersion composition containing a specific acryl-modified epoxy resin, an aromatic epoxy resin and a resol-type phenolic resin or an aqueous aminoplast resin, excellent in processability and corrosion resistance and applicable to the inside surface of a metal can. CONSTITUTION:(A) A modified epoxy resin of 10-60wt.% prepared by copolymerizing (i) an acryl-modified aromatic epoxy compound having 0.1-1.5 of acryloyl group and/or methacryloyl group par molecule which is prepared by reacting an aromatic epoxy resin having an epoxy equipment of 900-4500 with an acrylic acid and/or a methacrylic acid with (ii) an ethylenic monomer mixture containing acrylic aid and/or methacrylic acid and (B) 20-80wt.% of an aromatic epoxy resin are partially or totally neutralized with ammonia or amine. Subsequently, the product is added with 2-20wt.% of one or more than one selected from among (C) resol-type phenol, resins and (D) aqueous aminoplast resins to obtain the objective aqueous dispersion composition.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to aqueous dispersion compositions. More specifically, it relates to an aqueous dispersion composition for metal cans which is applied directly to a metal material or on a base paint, and more specifically to an aqueous dispersion composition which is applied to the inner surface of a metal can requiring high processability and corrosion resistance. It is a thing.

[0002]

2. Description of the Related Art Conventionally, a thin synthetic resin protective coating is usually provided on the inner surface of a metal can to prevent metal contents such as tin, tin-free steel and aluminum from directly contacting the contents and corroding the metal material. It has been subjected.

As the inner coating material, solvent type epoxy coating materials such as epoxy / phenol, epoxy / amino and epoxy / acrylic are usually used because of their excellent adhesion, corrosion resistance and flavor inhibition. However, since the above-mentioned coating material is based on a thermosetting resin, it has a drawback of poor workability. For this reason, in the case of uses and applications where processability is particularly required, use a vinyl chloride resin-based organosol paint based on a thermoplastic resin, with the drawback that it has many extracted components and is inferior in flavor inhibition resistance. I had no choice.

On the other hand, in recent years, epoxy / acrylic water-based paints have begun to be used in view of work hygiene / environmental measures or safety (non-hazardous) requirements. As disclosed so far, an epoxy resin is esterified with an acrylic resin containing a carboxyl group, neutralized with a base and dispersed in water (Japanese Patent Publication No. 59-37026), an acryloyl group The epoxy resin having is copolymerized with an ethylenic monomer containing acrylic acid or methacrylic acid,
Aqueous paint dispersed in water by the same method as above (Japanese Patent Publication No.
-7213), a carboxyl group-containing polymerizable monomer mixture is grafted onto an epoxy resin using a free radical generator and dispersed in water in the same manner as above (Japanese Patent Publication No. Sho 63-17869). is there. All of these are self-emulsifying type epoxy resin-based water-based paints in which the resin itself exhibits dispersibility, do not contain a surfactant for dispersion in water, and have excellent chemical performance, water resistance and the like. However, since the self-emulsifying epoxy resin-based water-based coating material uses an acrylic resin as an emulsifying component, it has poor processability in some cases, and has few reaction sites and a low cross-linking density, resulting in poor corrosion resistance.

[0005]

DISCLOSURE OF THE INVENTION The present invention solves various problems of the above conventional vinyl chloride resin-based organosol paints and self-emulsifying epoxy resin-based water-based paints,
In particular, it is an object of the invention to provide an aqueous coating composition having excellent processability and corrosion resistance.

[0006]

In order to solve the above problems, the present invention provides a modified epoxy resin (A) of 10 to 60% by weight, an aromatic epoxy resin (B) of 20 to 80% by weight, and a resol type. At least one selected from phenol resin (C) or aqueous aminoplast resin (D) 2
In an aqueous dispersion composition containing 20 to 20% by weight, the modified epoxy resin (A) is an ethylenic monomer containing an acrylic modified aromatic epoxy compound (a1) and acrylic acid and / or methacrylic acid. Mixture (a
2) is a modified epoxy resin obtained by copolymerizing the acrylic modified aromatic epoxy compound (a1) with an epoxy equivalent of 900 to 4500 aromatic epoxy resin (a3) and acrylic acid and / or methacrylic acid. Acid (a
4) An aqueous dispersion composition characterized by being an acrylic-modified aromatic epoxy compound having 0.1 to 1.5 acryloyl groups and / or methacroyl groups per molecule, which is obtained by reacting with 4). .

To obtain the aqueous dispersion composition of the present invention,
1) A modified epoxy resin (A) is mixed with an aromatic epoxy resin (B), and ammonia or amine is added to the mixture to neutralize and aqueous dispersion, and then a resol-type phenol resin (C) and / or Method of adding aqueous aminoplast resin (D), 2) mixing modified epoxy resin (A), aromatic epoxy resin (B), resol type phenol resin (C) and / or aqueous aminoplast resin (D) Therefore, there are two methods of neutralizing by adding ammonia or amine to form an aqueous dispersion.

Since the aqueous dispersion composition of the present invention contains the aromatic epoxy resin (B) which has not reacted with the acrylic resin, it is excellent in processability and has a curing component such as a resol type phenol resin (C) and an aqueous solution. Since the reactivity with the aminoplast resin (D) is high and the crosslink density is high, the corrosion resistance is improved.

The modified epoxy resin (A) of the present invention is an acrylic modified aromatic epoxy compound (a1) 20 described later.
To 90 wt% and acrylic acid and / or methacrylic acid-containing ethylenic monomer mixture (a2) 10
It is obtained by copolymerizing with 80% by weight.

Acrylic modified aromatic epoxy compound (a
If the content of 1) is less than 20% by weight, the processability is poor, and if it exceeds 90% by weight, an aromatic epoxy resin (B), a resol type phenol resin (C), an aqueous aminoplast resin (D).
Dispersibility with Therefore, it is preferably 20 to 90% by weight, and more preferably 30 to 80% by weight.

Acrylic modified aromatic epoxy compound (a
The ethylenic monomer mixture (a2) containing, as an essential component, acrylic acid and / or methacrylic acid copolymerized with 1) is a monomer copolymerizable with acrylic acid and / or methacrylic acid, for example, crotonic acid. Carboxyl group-containing vinyl-based monomers such as itaconic acid, maleic acid and fumaric acid; styrene, vinyltoluene, 2-methylstyrene, t-butylstyrene,
Styrene-based monomers such as chlorostyrene; methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, (meth) Isobutyl acrylate, n-amyl (meth) acrylate, isoamyl (meth) acrylate, n-hexyl (meth) acrylate, n-2 ethylhexyl (meth) acrylate,
(Meth) acrylic acid ester-based monomers such as n-octyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, and lauryl (meth) acrylate; 2-hydroxyethyl (meth) acrylate, Hydroxyl group-containing monomers such as hydroxypropyl (meth) acrylate and hydroxymethyl (meth) acrylate;
One or more N-substituted (meth) acrylic monomers such as N-methylol (meth) acrylamide and N-butoxymethyl (meth) acrylamide may be used.

The (meth) acrylic acid ester-based monomer is an acrylic acid ester-based monomer and / or a methacrylic acid ester-based monomer, and the hydroxyethyl (meth) acrylate is a hydroxyethyl acrylate and / or a hydroxymethacrylate. Ethyl, N-
The substituted (meth) acrylic monomer means an N-substituted acrylic monomer and / or an N-substituted methacrylic monomer.

As the polymerization catalyst of the above ethylenic monomer mixture, for example, an organic peroxide, a persulfate, an azobis compound, or a redox system combining these with a reducing agent can be used. Specific examples include benzoyl peroxide, perbutyl octate, t-butyl hydroperoxide, azobisisobutyronitrile, azobisvaleronitrile, 2,2 ^, -azobis (2-aminopropane) hydrochloride and the like. However, benzoyl peroxide and azobisisobutyronitrile are particularly preferable. These can be used generally in a proportion of 0.3 to 15 parts by weight based on 100 parts by weight of the reaction components.

Acrylic acid and / or used in the present invention
The composition ratio and type of the ethylenic monomer mixture (a2) containing methacrylic acid as an essential component are not particularly limited, but acrylic acid and / or methacrylic acid are 5% by weight or more, particularly 30 to 80% by weight. % Is preferred. The vinyl monomer copolymerizable with acrylic acid and / or methacrylic acid is preferably 95% by weight or less, particularly preferably 20 to 70%, and styrene and ethyl acrylate are preferable.

The reaction temperature of the acrylic modified aromatic epoxy compound (a1) of the present invention and the ethylenic monomer mixture (a2) containing acrylic acid and / or methacrylic acid as an essential component is preferably 100 ° C. or lower. .
When the temperature exceeds 100 ° C, the molecular weight of the modified epoxy resin (A) becomes small and the aromatic epoxy resin (B) or the like becomes difficult to disperse. In addition, acrylic acid and / or methacrylic acid are easily grafted to the epoxy resin in the acrylic modified aromatic epoxy compound (a1), and as a result, branched molecules are formed, and the processability is deteriorated.
It is preferable to react at 0 ° C or lower.

The reaction of the acrylic modified aromatic epoxy compound (a1) of the present invention with the ethylenic monomer mixture (a2) containing acrylic acid and / or methacrylic acid as an essential component should be carried out in an organic solvent system. The organic solvent used is preferably a solvent which dissolves (a1) and (a2) and is easily mixed with water. Examples thereof include alcohol-based, glycol-based, diglycol-based, acetate-based solvents and the like. 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 acetate, 3-methoxybutyl acetate, ethylene glycol mono Butyl ether acetate, 3-methyl-3-methoxybutyl acetate and the like can be mentioned. Although other solvents can be used, those which can be removed under reduced pressure during or after the production of the aqueous dispersion composition are preferable.

The acrylic modified aromatic epoxy compound (a1) of the present invention is obtained by reacting an aromatic epoxy resin (a3) having an epoxy equivalent of 900 to 4500 with acrylic acid and / or methacrylic acid (a4). , An acryl-modified aromatic epoxy compound having 0.1 to 1.5 acryloyl groups and / or methacroyl groups per molecule.

Examples of the aromatic epoxy resin (a3) having an epoxy equivalent of 900 to 4500 include bisphenol A type epoxy resin and bisphenol F type epoxy resin. 1.1 to 2.0 epoxy groups are contained in one molecule. I have. Among these epoxy resins, bisphenol A having a number average molecular weight of 1500 to 10,000
Type epoxy resin or bisphenol F type epoxy resin is preferable. Commercially available products are "Epicoat 1004" and "Epicoat 100 manufactured by Yuka Shell Epoxy Co., Ltd.
7 "," Epicoat 1009 "," Epicoat 1010 "," Epicoat 4009 "," Epicoat 4010 "and" YDF2004 "manufactured by Tohto Kasei Co., Ltd. and the like. One or more of the above epoxy resins can be selected and used.

The modified epoxy resin (A) obtained as described above is preferably used in an amount of 10 to 60% by weight. When it is less than 10% by weight, when it is made into an aqueous dispersion composition, other components, that is, the aromatic epoxy resin (B),
The dispersibility and stability of the resol type phenolic resin (C) and the aqueous aminoplast resin (D) is poor, and when it exceeds 60% by weight, the content of the aromatic epoxy resin (B) becomes relatively small, As a result, workability and corrosion resistance decrease. Therefore, the amount of the modified epoxy resin (A) used is preferably 10 to 60% by weight, more preferably 20 to 50% by weight.

The aromatic epoxy resin (B) used in the present invention may be the same as the aromatic epoxy resin (a3), and in particular, a bisphenol A type having an epoxy equivalent of 900 to 4500. Alternatively, a bisphenol F type epoxy resin is preferable because it has excellent workability and corrosion resistance.

Further, the aromatic epoxy resin (B) is 2
If it is less than 0% by weight, the reactivity is poor and the crosslink density is lowered, and as a result, the corrosion resistance is lowered. On the other hand, when it exceeds 80% by weight, the modified epoxy resin (A) is a relatively emulsified component.
Content decreases, and dispersion stability in water decreases.
Therefore, the amount of the aromatic epoxy resin (B) used is 20 to 20.
It is preferably 80% by weight, more preferably 50-80% by weight.

The resol type phenolic resin (C) used in the present invention includes a resin obtained by condensing an arbitrary phenol component and formaldehyde in the presence of a basic catalyst. Further, as the phenol component constituting the resol type phenol resin, o-cresol, p-cresol, p-tert-butylphenol, p-ethylphenol, 2,3-xylenol, 2,5-xylenol,
p-tert-aminophenol, p-nonylphenol,
Bifunctional phenols such as p-phenylphenol and p-cyclohexylphenol, carboxylic acid, m-cresol, m-ethylphenol, 3,5-xylenol, m
-Trifunctional phenols such as methoxyphenol, 2,
Monofunctional phenols such as 4-xylenol and 2,6-xylenol, bisphenol A: bisphenol B,
Tetrafunctional phenols such as bisphenol F may be used alone or in combination of two or more. As the basic catalyst, for example, ammonia, amine, hydroxide of alkaline earth metal, oxide of alkali metal, oxide of alkaline earth metal and the like can be used. If the resol type phenol resin is less than 2% by weight, the crosslinking density is low and the corrosion resistance is poor, and if it exceeds 20% by weight, the crosslinking density is too high and the processability is deteriorated. Therefore, 2 to 20% by weight is preferable.

The aqueous aminoplast resin (D) used in the present invention may or may not be alkyletherified with alcohol by addition condensation of an arbitrary amino component and formaldehyde in the presence of a basic catalyst. . As the amino component, there are melamine, benzoguanamine, acetoguanamine, urea, spiroguanamine, phthaloguanamine, and the like, and one or a combination of two or more types is used. Examples of the alcohol include methanol, ethanol, isobutanol, n-butanol and the like, and a single kind or a combination of two or more kinds is used. Preferred are melamine or benzoguanamine resins etherified with methanol or ethanol. As a commercially available product, Cymel manufactured by Mitsui Cyanamid Co., Ltd.
300, 303, 325, 701, 1123, 1170, My Court 101
Etc. If the water-based aminoplast resin is less than 2% by weight, the crosslink density is low and the corrosion resistance is inferior, and if it exceeds 20% by weight, the crosslink density is too high and the workability is deteriorated.
20% by weight is preferred.

In the present invention, the resol type phenol resin and the aminoplast resin may be used in combination, and the total amount of the combination is preferably 2 to 20% by weight for the same reason as above.

The ammonia or amine used in the present invention includes, for example, alkylamines such as trimethylamine, triethylamine and butylamine, alcohol amines such as dimethylaminoethanol, diethanolamine and aminomethylpropanol, and volatile amines such as morpholine.

If desired, a solvent, a surfactant or a defoaming agent may be added to the aqueous dispersion composition of the present invention to improve the coatability. Further, it is possible to add a wax, which is a lubricant, to the aqueous dispersion composition of the present invention in order to prevent the coating film from being scratched during processing and transportation after forming the coating film.

As a base material 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. The aqueous dispersion of the present invention may be coated on an epoxy-based, vinyl-based or the like primer,
Alternatively, it may be directly coated on the metal material. As a coating method, various known methods such as roll coater coating, spray coating, dip coating and electrodeposition coating can be applied, and among them, roll coater coating and spray coating are preferable. The drying and curing conditions are 150 to 230 ° C and 1 to
It is preferably 30 minutes or 240 to 300 ° C. for 15 to 60 seconds.

[0028]

EXAMPLES Next, the present invention will be described more specifically by way of examples. In the examples, "parts" and "%" indicate "parts by weight" and "% by weight", respectively.

Production Example 1 Production of Modified Epoxy Resin (A1) Solution (1) Epicoat 1009 (manufactured by Yuka Shell Epoxy Co., Ltd.): (a3) 350.0 parts (2) ethylene glycol monobutyl ether 186.2 parts (3) methacrylic acid : (A4) 2.1 parts (4) 25% aqueous sodium hydroxide solution 0.2 parts (5) Hydroquinone 0.005 parts (6) n Butanol 161.7 parts (7) Styrene 37.5 parts (8) Ethyl acrylate 45.0 parts (9) Methacrylic acid 67.5 Parts (10) n-butanol 142.3 parts (11) azobisisobutyronitrile 7.5 parts (12) azobisisobutyronitrile 0.8 parts (13) azobisisobutyronitrile 0.8 parts

A four-necked flask was charged with the above (1) to (5), the internal temperature was raised to 120 to 130 ° C., the reaction was allowed to proceed under a nitrogen stream, and cooling was carried out when the acid value became 0.2 or less. (6) was added when the temperature reached 100 ° C. to obtain an acrylic modified aromatic epoxy compound (a1) solution. The solution (a1) thus obtained was kept at 100 ° C. with stirring, and (7) to (11)
The mixed solution of was added dropwise over 2 hours, 1 hour after the addition of (12), and 1 hour after the addition of (13), the mixture was stirred for 1 hour while maintaining the same temperature and cooled to 50 ° C. A 50% modified epoxy resin (A1) solution was obtained.

Production Example 2 Production of Modified Epoxy Resin (A2) Solution (1) Epicoat 1009 (produced by Yuka Shell Epoxy Co., Ltd.): (a3) 300.0 parts (2) Ethylene glycol monobutyl ether 159.5 parts (3) Methacrylic acid : (A4) 1.8 parts (4) 25% aqueous sodium hydroxide solution 0.2 parts (5) Hydroquinone 0.005 parts (6) n Butanol 138.5 parts (7) Styrene 50.0 parts (8) Ethyl acrylate 60.0 parts (9) Methacrylic acid 90.0 Parts (10) n butanol 188.0 parts (11) benzoyl peroxide 10.0 parts (12) benzoyl peroxide 1.0 parts (13) benzoyl peroxide 1.0 parts

In the same manner as in Production Example 1, (1) to (5) were charged to proceed the reaction, cooling was started when the acid value became 0.2 or less, and (6) was carried out when the acid value reached 100 ° C. Then, an acrylic modified aromatic epoxy compound (a1) solution was obtained. The solution (a1) thus obtained was kept at 100 ° C. with stirring, and the solution (7) to (1
The mixture of 1) was added dropwise over 2 hours, and 1 hour after the addition (12)
Was added, and 1 hour later, (13) was added, and the mixture was stirred for 1 hour while maintaining the same temperature and cooled to 50 ° C. to obtain a modified epoxy resin (A2) solution having a solid content of about 50%.

Production Example 3 Production of Modified Epoxy Resin (A3) Solution (1) Epicoat 1010 (produced by Yuka Shell Epoxy Co., Ltd.): (a3) 200.0 parts (2) Ethylene glycol monobutyl ether 106.3 parts (3) Methacrylic acid : (A4) 1.2 parts (4) 25% aqueous sodium hydroxide solution 0.2 parts (5) Hydroquinone 0.005 parts (6) n Butanol 92.3 parts (7) Styrene 60.0 parts (8) Ethyl acrylate 60.0 parts (9) Methacrylic acid 180.0 Parts (10) n butanol 282.0 parts (11) azobisisobutyronitrile 15.0 parts (12) azobisisobutyronitrile 1.5 parts (13) azobisisobutyronitrile 1.5 parts

In the same manner as in Production Example 1, (1) to (5) were charged to proceed the reaction, cooling was started when the acid value became 0.2 or less, and (6) was carried out when the acid value reached 100 ° C. Then, an acrylic modified aromatic epoxy compound (a1) solution was obtained. The solution (a1) thus obtained was kept at 100 ° C. with stirring, and the solution (7) to (1
The mixture of 1) was added dropwise over 2 hours, and 1 hour after the addition (12)
Was added, and 1 hour later, (13) was added, and the mixture was stirred for 1 hour while maintaining the same temperature and cooled to 50 ° C. to obtain a modified epoxy resin (A3) solution having a solid content of about 50%.

Production Example 4 Production of Modified Epoxy Resin (A4) Solution (1) Epicoat 1007 (produced by Yuka Shell Epoxy Co., Ltd.): (a3) 350.0 parts (2) ethylene glycol monobutyl ether 186.2 parts (3) methacrylic acid : (A4) 3.1 parts (4) 25% aqueous sodium hydroxide solution 0.2 parts (5) Hydroquinone 0.005 parts (6) n Butanol 160.7 parts (7) Styrene 37.5 parts (8) Ethyl acrylate 45.0 parts (9) Methacrylic acid 67.5 Parts (10) n-butanol 142.3 parts (11) azobisisobutyronitrile 7.5 parts (12) azobisisobutyronitrile 0.8 parts (13) azobisisobutyronitrile 0.8 parts

A 4-necked flask was charged with (1) to (5), the internal temperature was raised to 120 to 130 ° C., the reaction was allowed to proceed under a nitrogen stream, and cooling was started when the acid value became 0.2 or less. Then 100
When the temperature reached ℃, (6) was added to obtain an acryl-modified aromatic epoxy compound (a1) solution. Obtained (a1)
While maintaining the solution at 100 ° C and stirring, the mixed solution of (7) to (11) was added dropwise over 2 hours, and 1 hour after the addition, (12) was added,
After 1 hour, (13) was added, and the mixture was stirred for 1 hour while maintaining the same temperature and cooled to 50 ° C. to obtain a modified epoxy resin (A4) solution having a solid content of about 50%.

Production Example 5 Production of Resol-type Phenolic Resin (C) Solution (1) p-Cresol 417.7 parts (2) Formalin 40% n-butanol solution 580.1 parts (3) Magnesium hydroxide 2.2 parts 4-neck flask- , 100 ° C under nitrogen stream
After reacting for 2.5 hours with water, neutralize with phosphoric acid, add a large amount of water such as xylene / n-butanol / cyclohexanone = 1/1/1, and leave for 5 hours to separate the aqueous layer containing the generated salt. It was removed and further azeotropically dehydrated to obtain a resol type phenol resin (C) solution having a solid content of about 35%.

Production Example 6 Production of Aqueous Aminoplast Resin (D) Solution (1) Cymel 1123 350.0 parts (2) Ethylene glycol monoethyl ether 650.0 parts A 4-necked flask was charged with at 30 ° C. under a nitrogen stream. Aqueous aminoplast resin (D) that dissolves and has a solid content of approximately 35%
A solution was obtained.

Example 1 (1) Modified epoxy resin solution (A1) 250.0 parts (2) Epicoat 1009 (produced by Yuka Shell Epoxy Co., Ltd.): (B) 100.0 parts (3) Ethylene glycol monobutyl ether 100.0 parts (4) ) Resol type phenol resin (C) solution 71.4 parts (5) Dimethylaminoethanol 17.5 parts (6) Ion-exchanged water 461.1 parts (4) A four-necked flask is charged with (1) to (3) and heated to 100 ° C.
(2) was dissolved, cooled to 80 ° C., (4) to (5) were added, and (6) was added little by little to obtain an aqueous dispersion having a solid content of about 25%.

Examples 2 to 11 In the same manner as in Example 1, modified epoxy resins (A1) to (A4) solutions having the formulations shown in Tables 1 and 2, Epicoat 1009 as an aromatic epoxy resin (B), 1007 and one or more kinds selected from a resol type phenol resin (C) solution or an aqueous aminoplast resin (D) solution are used to neutralize methacrylic acid in the charged acrylic resin component with dimethylethanolamine at 100 mol%. Then, ion-exchanged water was added little by little to obtain an aqueous dispersion having a solid content of about 25%.

Example 12 (1) Modified epoxy resin solution (A1) 250.0 parts (2) Epicoat 1009 (manufactured by Yuka Shell Epoxy Co., Ltd.): (B) 100.0 parts (3) Ethylene glycol monobutyl ether 100.0 parts (4) ) Dimethylaminoethanol 17.5 parts (5) Ion-exchanged water 461.1 parts (6) Resol type phenol resin (C) solution 71.4 parts Charge (1) to (3) into a 4-necked flask and heat to 100 ° C.
(2) was dissolved, cooled to 80 ° C, (4) was added, (5) was added little by little, and (6) was further added to obtain an aqueous dispersion having a solid content of about 25%. .

[0042]

[Table 1]

[0043]

[Table 2]

Comparative Examples 1 to 6 In the same manner as in Example 1 above, except that the formulation shown in Table 3 was changed, the same procedure as in Example 1 was carried out to obtain solid content.
A 25% aqueous dispersion was obtained.

[0045]

[Table 3]

(Preparation of Paint) The organic solvent contained in the aqueous dispersions obtained in the above Examples and Comparative Examples was removed under reduced pressure to obtain a solid content of 25% and a content of 15% in the paint. I adjusted it to be.

(Performance Test) Examples 1 to 12 and Comparative Examples 1 to 1
The storage stability of the aqueous coating composition obtained in No. 6 as a coating was evaluated, and the physical properties of the coating film were evaluated for the test panel prepared under the following conditions. The results are shown in Tables 4-5.

Test panel preparation conditions: 0.30 mm aluminum plate shape
Paint with a bar coater to a size of 10μ.
A test panel was prepared by baking for minutes.

The various test methods in Tables 4 to 5 are as follows. (1) Storage stability of paint: Stored in a thermostat at 50 ° C and periodically evaluated the appearance and properties. Good storage stability ・ ・ ・ ・ ○ Abnormalities such as gelation, sedimentation, and separation occurred during storage ・ ・ ・ ・ ×

(2) Adhesion: approx.
Make a width of 1.5 mm and make 11 cuts in each of the vertical and horizontal directions. The number of unpeeled parts of the crevices when strongly peeled off with a 24 mm width cellophane adhesive tape is shown in the molecule.

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

(4) Workability: The coated plate was cut into a size of 40 mm × 50 mm, the coating film was placed outside, and the test site was folded in two so that the test site was 40 mm, and between the two folded test pieces. thickness
After sandwiching two 0.30 mm aluminum plates and dropping a load of 3 kg from the height of 45 cm to the bending part, 6.
The current value of 2 cm width of the processed part was measured after applying 0 V × 10 seconds.

(5) Corrosion resistance: using a knife on the coated surface ×
The test piece with the notch is marked at 125 ℃ in 1% saline solution.
Treat for 40 minutes and store at 50 ° C for 1 week, and judge the degree of corrosion near the X mark. No abnormality ・ ・ ・ ・ ○ Mark slightly corroded ・ ・ ・ ・ △ mark Marked corrosion ・ ・ ・ ・ × mark

(6) Flavor resistance (abbreviated as flavor): Made of heat-resistant glass filled with treated water so that the tap water treated with activated carbon becomes 1 ml per 1 cm ^{2 of the} test piece coating film. The bottle was put in a bottle, capped, and sterilized at 125 ° C. for 45 minutes, and then the change in flavor (flavor) of the content liquid was evaluated. No change ・ ・ ・ ・ ○ mark Slight change ・ ・ ・ ・ △ mark Significant change ・ ・ ・ ・ × mark

[0055]

[Table 4]

[0056]

[Table 5]

[0057]

[Effect] The present invention provides a specific modified epoxy resin (A) 10
-60% by weight, aromatic epoxy resin (B) 20-80
%, And 2 to 20% by weight of at least one selected from a resol type phenolic resin (C) or an aqueous aminoplast resin (D), which is an unmodified epoxy resin. Since it contains a large amount of C, the workability is excellent, and since the reactivity with the cured resin (resole type phenol resin, aqueous aminoplast resin) is high, the crosslink density is increased and the corrosion resistance is excellent.

Claims (4)

[Claims] 1. Modified epoxy resin (A) 10 to 60% by weight
And aromatic epoxy resin (B) 20 to 80% by weight
Is partially or entirely neutralized with ammonia or amine to be aqueously dispersed, and then at least one or more selected from resol type phenolic resin (C) or aqueous aminoplast resin (D) 2 to 20 In the aqueous dispersion composition, the modified epoxy resin (A) is an acrylic modified aromatic epoxy compound (a1) and an ethylenic monomer mixture (a2) containing acrylic acid and / or methacrylic acid. )
A modified epoxy resin obtained by copolymerizing the acrylic modified aromatic epoxy compound (a1) with an acrylic epoxy resin (a3) having an epoxy equivalent of 900 to 4500 and acrylic acid and / or methacrylic acid ( a
4) An aqueous dispersion composition characterized by being an acrylic modified aromatic epoxy compound having 0.1 to 1.5 acryloyl groups and / or methacroyl groups per molecule, which is obtained by reacting with 4). 2. A modified epoxy resin (A) of 10 to 60% by weight, an aromatic epoxy resin (B) of 20 to 80% by weight, and a resole type phenol resin (C) or an aqueous aminoplast resin (D). At least one or more 2
In an aqueous dispersion composition in which a mixture of 20 to 20% by weight is partially or wholly neutralized with ammonia or amine, the modified epoxy resin (A) is an acrylic modified aromatic epoxy compound ( a1) and an ethylenic monomer mixture (a2) containing acrylic acid and / or methacrylic acid
A modified epoxy resin obtained by copolymerizing the acrylic modified aromatic epoxy compound (a1) with an acrylic epoxy resin (a3) having an epoxy equivalent of 900 to 4500 and acrylic acid and / or methacrylic acid ( a
4) An aqueous dispersion composition characterized by being an acrylic modified aromatic epoxy compound having 0.1 to 1.5 acryloyl groups and / or methacroyl groups per molecule, which is obtained by reacting with 4). 3. The aqueous dispersion composition according to claim 1, wherein the aromatic epoxy resin (B) has an epoxy equivalent of 900 to 4,500. 4. The aromatic epoxy resins (a3) and (B) are bisphenol A type or bisphenol F type.
The aqueous dispersion composition according to any one of claims 1 to 3, which is a mold.