JP2003119245A - Aqueous dispersion of vinyl-modified epoxy ester resin, water-based coating composition, and coated object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-based coating composition and a water-based coating composition capable of obtaining a coating film excellent in corrosion resistance and hardness, particularly immediately after coating film formation, without being restricted by a coating method. To provide an aqueous dispersion of a vinyl-modified epoxy ester resin for obtaining the same. SOLUTION: A mixture of a vinyl compound containing an acid group-containing monomer is graft-polymerized in the presence of a condensate obtained by condensing an epoxy resin and a fatty acid as essential components in a composition such that the epoxy group becomes excessive. After neutralizing at least a part of the acid groups in the obtained graft polymer, it is dispersed in water.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aqueous dispersion of a vinyl-modified epoxy ester resin having excellent corrosion resistance and capable of obtaining a coating film having high hardness, an aqueous coating composition containing the aqueous dispersion, and the aqueous dispersion containing the same. Regarding painted objects. The water-based coating composition obtained in the present invention is used for various coatings such as metal products in general, exterior and interior of buildings, coating of building materials, coating of structures such as tanks and bridges, coating of home appliances, automobile repair coating, etc. It is used for various purposes, and therefore, coated products include those coated on various base materials such as metal products, buildings, building materials, structures such as tanks and bridges, home appliances, automobiles, etc. .

[0002]

2. Description of the Related Art Various rust-preventive paints have been used for the purpose of coating metal materials to prevent rust. Most of such rust-preventive paints are oil-based paints, and the large amount of organic solvent contained therein is not preferable in terms of workability and safety, and has recently been required to be converted to water-based paints because it can be a source of environmental pollution. Is high.

By the way, this type of water-based coating contains a water-soluble or water-dispersible so-called water-based resin as a vehicle. To improve the solubility or dispersibility of such a resin in water, a resin is used. When a large amount of so-called hydrophilic groups such as a carboxyl group, a hydroxyl group or a (poly) ethylene oxide group is introduced into the molecule of, or a dispersing component (dispersant) such as an emulsifier is added to the resin. Many.

Therefore, the water resistance and corrosion resistance of water-based paints are
Generally inferior to oil-based paints. Even in such a water-based paint, when it is electrodeposited by the electrodeposition coating system, the corrosion resistance of the coating film can be excellent,
In this case, there is a problem that a special device such as a baking process at a high temperature or an electrodeposition tank is required, and there is a restriction that the coating is difficult depending on the shape of the object to be coated.

In order to overcome such a problem, Japanese Patent Laid-Open No. Hei 4
-292666 proposes an aqueous dispersion of an epoxy ester resin comprising a specific amount of an epoxy resin and a fatty acid, and an amount of another compound that can react with these in an amount of 1 to 15% or less. However, although the coating film according to the present invention certainly has rust preventive properties on the level of an oil-based paint, it has a drawback that the hardness immediately after the coating film is formed is soft.

[0006]

The object of the present invention is to improve the drawbacks of the conventional water-based paint as described above, to provide excellent corrosion resistance without being restricted by the coating method, and hardness, especially immediately after the coating film is formed. It is intended to provide an aqueous coating composition capable of obtaining a coating film having excellent hardness and an aqueous dispersion of a vinyl-modified epoxy ester resin for obtaining the aqueous coating composition.

[0007]

Therefore, the present inventors have
Focusing on the problems as described above, as a result of repeated intensive research, using an aqueous coating composition containing an aqueous dispersion of a vinyl-modified epoxy ester resin having a specific resin composition,
A special coating device such as an electrodeposition system, a wide range of coating means such as air spray, airless spray, brush or dipping, and a coating film formed under a wide range of drying conditions such as room temperature drying, forced drying or baking. However, they have found that they have excellent corrosion resistance and excellent hardness, and have completed the present invention.

That is, the present invention comprises an acid group-containing monomer capable of reacting with an epoxy resin (a) and a fatty acid (b) in the presence of a condensate (c) obtained by condensing them as essential components. A water-based dispersion of a vinyl-modified epoxy ester resin, which is obtained by graft-polymerizing a mixture (d) of vinyl compounds, neutralizing at least a part of acid groups in the obtained graft polymer, and then dispersing the mixture in water. The epoxy group-derived epoxy group and the fatty acid-derived carboxyl group have an equivalent ratio of excess epoxy groups, and the mixture (d) is used in a total amount of the condensate (c) and the mixture (d) of 100.
An aqueous dispersion of a vinyl-modified epoxy ester resin, characterized by being 15 parts by weight or more based on parts by weight.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION First, the vinyl-modified epoxy ester resin used in the present invention will be described. This vinyl-modified epoxy ester resin is obtained by a polymerization reaction of a condensate (c) obtained by an addition reaction of an epoxy resin (a) with a fatty acid (b) and a mixture (d) of a vinyl compound. It is necessary to use the epoxy resin (a) and the fatty acid (b) in such a ratio that the equivalent ratio of the epoxy group and the carboxyl group derived from the fatty acid in the epoxy resin is in excess of the epoxy group. The remaining epoxy groups are
It is possible to react with an acid group-containing compound, preferably 1
It is preferable to react with the basic acid compound (e). These components may be charged into a reaction apparatus, and if necessary, each component may be bonded to an epoxy resin through an ester bond under heating conditions in the presence of a known and commonly used esterification catalyst. The resulting fatty acid epoxy ester (condensate (c) comprising the epoxy resin (a), the fatty acid (b) and preferably the monobasic acid compound (e), hereinafter referred to as an epoxy ester) has a high viscosity at room temperature. It becomes a liquid substance.

Then, the obtained epoxy ester and a mixture (d) of a vinyl compound containing an acid group-containing monomer are added, if necessary, in an organic solvent in the presence of a radical polymerization initiator.
A polymerization reaction is performed under heating conditions to obtain a graft polymer of an epoxy ester and a vinyl compound (vinyl modified epoxy ester resin). The reaction conditions at this time are about 1 to 1 gauge pressure.
Polymerization may be carried out at 00 kg / cm ² and a reaction temperature of about 50 to 150 ° C. In some cases, the polymerization may be performed under a pressure higher than this or a temperature lower than this. The nonvolatile content at the time of polymerization is 1 to 90% by weight, preferably 4
It should be set in the range of 0 to 80% by weight.

The mixture (d) of vinyl compounds containing an acid group-containing monomer is an aromatic vinyl compound, a (meth) acrylic acid alkyl ester having an alkyl group having 4 or more carbon atoms,
It is preferably a mixture containing an acid group-containing vinyl compound. Moreover, the usage ratio is such that the amount of the mixture (d) of the vinyl compound containing the acid group-containing monomer is the epoxy resin (a).
The total amount of the condensate (c) containing the acid and the fatty acid (b) and the mixture (d) of the vinyl compound containing the acid group-containing monomer 10
It is preferably 15 parts by weight or more with respect to 0 parts by weight. Such a raw material ratio is determined in consideration of the balance between the corrosion resistance and the hardness of the resulting coating film. In the present invention, the amount of the mixture (d) of vinyl compounds containing the acid group-containing monomer is 1
If it is 5% or less, the desired balance between corrosion resistance and hardness is lacking.

The intended vinyl-modified epoxy ester resin has an acid group derived from an acid group-containing monomer, and this acid group is essential for making it aqueous in the subsequent step. As the concentration of such an acid group, it is preferable that the acid value of solid content in the vinyl-modified epoxy ester resin is in the range of about 15 to 50 mgKOH / g. Within this range, good water dispersibility can be obtained, and good adhesion to the substrate and good pigment dispersibility can be obtained. Furthermore, the obtained coating film has corrosion resistance, water resistance, alkali resistance, etc. The performance involving water can also be made excellent.

The number average molecular weight of the vinyl-modified epoxy ester resin is preferably in the range of 1,000 to 100,000. Within this range, excellent corrosion resistance, water resistance, etc. can be obtained, and water dispersion can be favorably carried out.

Next, a part or all of the acid groups in the obtained vinyl-modified epoxy ester resin are neutralized with a basic compound, and the neutralized polymer is dissolved or dispersed in water to obtain the present invention. An aqueous dispersion of the vinyl-modified epoxy ester resin is obtained. If the concentration of acid groups is high,
Alternatively, when the degree of neutralization is high, a water-soluble aqueous resin can be prepared, and when the acid group concentration is low or the degree of neutralization is low, a self-dispersible water-dispersed aqueous resin is prepared. You can Further, after the aqueous resin is prepared, the organic solvent in the system can be distilled off and removed, if necessary.

When the copolymer thus prepared is dispersed in water, an emulsifier and / or a dispersion stabilizer may be used together. As the emulsifier, various emulsifiers such as an ionic emulsifier and a nonionic (nonionic) emulsifier can be used.

As the anionic emulsifiers, only representative ones are specifically exemplified: alkyl (benzene) sulfonate, alkyl sulfate salt, polyoxyethylene alkylphenol sulfate salt, styrene sulfonate, vinyl sulfate salt, or , And derivatives thereof.

The term "salt" as used herein refers to salts of alkali metal hydroxides; salts of volatile bases such as ammonia and triethylamine.

Specific examples of the cationic emulsifiers include lauryltrimethylammonium chloride, didecyldimethylammonium chloride, lauryldimethylbenzylammonium chloride, and the like.

As nonionic emulsifiers, only typical ones are exemplified. Polyoxyethylene alkylphenol ether, polyoxyethylene alkyl ether, polyoxyethylene higher fatty acid ester, ethylene oxide-propylene oxide block copolymer. , Or derivatives thereof, and these may be used alone or in combination of two or more kinds.

The amount of these emulsifiers used is preferably within the range of 10 parts by weight or less, and more preferably within the range of 0.1 to 5 parts by weight, based on 100 parts by weight of the total resin solid content. preferable.

As the dispersion stabilizer, various water-soluble oligomers selected from the group consisting of polycarboxylic acids and sulfonates, polyvinyl alcohol, hydroxyethyl cellulose, starch, maleated polybutadiene, maleated alkyd resin, poly Examples include various synthetic or natural water-soluble or water-dispersible water-soluble polymer substances such as acrylic acid (salt), polyacrylamide, water-soluble or water-dispersible acrylic resin, and one or more of these may be used. Mixtures can be used.

The amount of these dispersion stabilizers used is preferably within the range of 10 parts by weight or less, and more preferably within the range of 0.1 to 5 parts by weight, based on 100 parts by weight of the total resin solid content. Is more preferable. The step of dispersing in water may be at room temperature or under heating, but under heating, a temperature of 70 ° C. or lower is preferable in order to avoid skinning of the liquid surface. At the time of dispersion, it is preferable to use a device such as a disper, a homomixer, or a multi-screw kneading extruder.

Specific examples of the epoxy resin (a) which is a raw material of the vinyl-modified epoxy ester resin include bisphenol type epoxy resin, alicyclic epoxy resin, phenol novolac type epoxy resin, polyethylene glycol type epoxy resin, epoxidized polybutadiene and the like. Various epoxy resins of

As the bisphenol type epoxy resin,
Epicron 850, 1050, 3050, 405
0, 7050 (above, Dainippon Ink and Chemicals, Inc.
Epoxy resin), Epicoat 828, 834,
1001, 1004, 1007, 1009 (Epoxy resin manufactured by Shell in the Netherlands), DER
660, 661J, 662, 664J, 667
J, 668, 669J (Epoxy resin manufactured by Dow Chemical Co., USA) can be used.

As the alicyclic epoxy resin, UNOX 201, 289 (epoxy resin manufactured by Union Carbide Co., USA) can be used.

As the phenol novolac type epoxy resin, Epicron N-740, 775 (above, Dainippon Ink and Chemicals, Inc.) or the like can be used,

As the polyethylene glycol type epoxy resin, Epicoat 812 (Epoxy resin manufactured by Shell Co., Netherlands), Epolite 40E, 200E,
400E (Epoxy resin manufactured by Kyoeisha Co., Ltd.) or the like can be used,

As the epoxidized polybutadiene, BF
-1000 (epoxy resin manufactured by ADEKA ARGUS CORPORATION) or the like can be used.

These can be used as a mixture of one kind or two or more kinds. Of these, the bisphenol type epoxy resin is excellent in reactivity with other raw materials used in combination and in corrosion resistance, and therefore it is desirable to use the bisphenol type epoxy resin as a main component.

The fatty acid (b) which is a raw material for the vinyl-modified epoxy ester resin is not particularly limited, but representative examples thereof include tung oil fatty acid, linseed oil fatty acid,
Dehydrated castor oil fatty acid, castor oil fatty acid, tall oil fatty acid, cottonseed oil fatty acid, soybean oil fatty acid, olive oil fatty acid,
Examples thereof include dry oil fatty acids such as safflower oil fatty acid and rice bran oil fatty acid, and non-drying oil fatty acids such as hydrogenated coconut oil fatty acid, coconut oil fatty acid and palm oil fatty acid. Furthermore, unsaturated fatty acids such as oleic acid, linoleic acid, linoleic acid, eleostearic acid and ricinoleic acid, and saturated fatty acids such as octylic acid, ularylic acid and stearic acid, which are obtained by purifying these fatty acids, can be exemplified. These are 1
It may be used as a kind or a mixture of two or more kinds.

The unreacted epoxy group derived from the epoxy resin (a) can be capped by using an acid group-containing compound. In this case, the epoxy group in the epoxy resin and
It is preferable to mix and use such that the sum of the carboxyl group in the fatty acid and the carboxyl group in the acid group-containing compound is equal.

Examples of the above-mentioned acid group-containing compound include benzoic acid, p-tert-benzoic acid, isooctanoic acid, isodecanoic acid, cyclohexanoic acid, phthalic acid, isophthalic acid,
Terephthalic acid, tetrahydrophthalic acid, hymic acid (product of Hitachi Chemical Co., Ltd.), maleic acid, fumaric acid,
Organic carboxylic acids such as adipic acid, sebacic acid, dimer acid, trimellitic acid and pyromellitic acid can be exemplified. Of these, the use of the monobasic acid compound (e) is preferable. Examples of the monobasic acid compound (e) include known organic carboxylic acids such as benzoic acid, p-tert-benzoic acid, isooctanoic acid, isodecanoic acid and cyclohexanoic acid.

Next, specific examples of the compound that can be used as the mixture (d) of the vinyl compound containing the acid group-containing monomer will be described. (1) First, as the acid group-containing monomer, (meth) acrylic acid, 2-carboxyethyl acrylate, crotonic acid,
Vinyl acetic acid, monovinyl adipate, monovinyl sebacate, monomethyl itaconate, monomethyl maleate,
Monomethyl fumarate, mono [2- (meth) acryloyloxyethyl] succinate, mono [2- (meth) phthalate
Acryloyloxyethyl], hexahydrophthalic acid mono [2- (meth) acryloyloxyethyl], monocarboxylic acids having an unsaturated double bond such as sorbic acid;
Typical examples are monomers having a carboxyl group such as unsaturated dicarboxylic acids such as itaconic acid, maleic acid and fumaric acid.

In addition to the above acid group-containing monomer, the following monomers can be used. (2) Methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-
Butyl (meth) acrylate, iso-butyl (meth)
Acrylate, tert-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, octadecyl (meth) acrylate, docosanyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, bornyl ( Various cycloalkyl (meth) acrylates such as (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate;

Cyclopentylmethyl (meth) acrylate, cyclohexylmethyl (meth) acrylate, 2-
Alkyl-substituted cycloalkyl (meth) acrylates such as cyclohexylethyl (meth) acrylate; alkyl groups or aralkyl such as various aralkyl (meth) acrylates such as benzyl (meth) acrylate or 2-phenylethyl (meth) acrylate (Meth) acrylic acid esters having a group;

(3) Styrene, p-tert-butylstyrene, α-methylstyrene, vinyltoluene,
Various aromatic vinyl compounds.

Among these, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth), among those exemplified in (2) above in combination with the essential component (1). Acrylate, 2
-Ethylhexyl (meth) acrylate, lauryl (meth) acrylate, octadecyl (meth) acrylate, docosanyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, bornyl (meth) acrylate, isobornyl (meth) acrylate, di Various cycloalkyl (meth) acrylates such as cyclopentanyl (meth) acrylate;

Cyclopentylmethyl (meth) acrylate, cyclohexylmethyl (meth) acrylate, 2-
Use of a (meth) acrylic acid alkyl ester having an alkyl group having 4 or more carbon atoms, a cycloalkyl group, or an alkyl-substituted cycloalkyl group, such as an alkyl-substituted cycloalkyl (meth) acrylate such as cyclohexylethyl (meth) acrylate Further, it is more preferable to use (meth) acrylic acid alkyl ester having an alkyl group having 4 or more carbon atoms.
Further, it is preferable to use the above-mentioned monomers (1), (2) and (3).

In addition to the above-mentioned monomers, various monomers shown below can be used as the mixture (d) of the vinyl compound containing the acid group-containing monomer. (4) 2-methoxyethyl (meth) acrylate, 4-
Various types of ω such as methoxybutyl (meth) acrylate
-Alkoxyalkyl (meth) acrylates;

(5) Vinyl esters of carboxylic acids having a total carbon number of 4 or less such as vinyl acetate and vinyl propionate, vinyl esters of carboxylic acids such as vinyl pivalate, vinyl versatate or vinyl benzoate. ;

(6) Various crotonic acid esters such as methyl crotonic acid, ethyl crotonic acid, c-n-butyl crotonic acid and 2-ethylhexyl crotonic acid;

(7) Various unsaturated dibasic acid diesters such as dimethylmalate, dimethylfumarate, dimethylitaconate, di-n-butylmalate, di-n-butylfumarate, di-n-butylitaconate Kind;

(8) Various cyano group-containing vinyl monomers such as (meth) acrylonitrile and crotononitrile;

(9) Vinyl fluoride, vinylidene fluoride,
Various fluoroolefins such as tetrafluoroethylene, chlorotrifluoroethylene, hexafluoropropylene;

(10) Various chlorinated olefins such as vinyl chloride and vinylidene chloride;

(11) Various α-olefins such as ethylene and propylene;

(12) Ethyl vinyl ether, n-propyl vinyl ether, n-butyl vinyl ether, n-
Various alkyl vinyl ethers such as hexyl vinyl ether;

(13) Cyclopentyl vinyl ether,
Various cycloalkyl vinyl ethers such as cyclohexyl vinyl ether and 4-methylcyclohexyl vinyl ether;

(14) N, N-Dimethyl (meth) acrylamide, N- (meth) acryloylmorpholine, N-
Tertiary amide group-containing vinyl monomers such as (meth) acryloylpyrrolidine and N-vinylpyrrolidone;

(15) 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2
-Hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, methyl (2-hydroxymethyl) acrylate, ethyl (2-hydroxymethyl) acrylate, butyl (2-hydroxymethyl)
Of acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth) acrylate (Meth) acrylic acid esters containing a hydroxyl group such as:

(16) Allyl compounds containing a hydroxyl group such as allyl alcohol and 2-hydroxyethyl allyl ether;

(17) Vinyl ether compounds containing a hydroxyl group such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and 6-hydroxyhexyl vinyl ether;

(18) Unsaturated carboxylic acid amide compounds having a hydroxyl group such as N-methylol (meth) acrylamide and N-methylol crotonic acid amide;

(19) Hydroxyl group-containing unsaturated fatty acid such as ricinoleic acid; (20) Hydroxyl group-containing unsaturated fatty acid ester such as alkyl ricinoleate;

(21) Monomers and the like obtained by addition reaction of various hydroxyl group-containing monomers such as the above (15) to (20) with ε-caprolactone adducts;

(22) N-methylaminoethyl (meth)
Acrylate, N-ethylaminoethyl (meth) acrylate, N-n-butylaminoethyl (meth) acrylate, N-tert-butylaminoethyl methacrylate, N-methylaminoethyl crotonate, N-ethylaminoethyl crotonate, N A vinyl monomer containing a secondary amino group, such as -n-butylaminoethyl crotonate;

(23) Vinyl acetoacetate, 2-acetoacetoxyethyl (meth) acrylate, 2-acetoacetoxypropyl (meth) acrylate, 3-acetoacetoxypropyl (meth) acrylate, 3-acetoacetoxybutyl (meth) acrylate, A monomer having an active methylene group, such as 4-acetoacetoxybutyl (meth) acrylate, allylacetoacetate, and 2,3-di (acetoacetoxy) propyl methacrylate.

(24) Vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinyltris (2-methoxyethoxy) silane, allyltrimethoxysilane, 2-trimethoxysilylethyl vinyl ether, 3-trimethoxysilylpropyl vinyl ether , 3- (methyldimethoxysilyl) propyl vinyl ether, 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane, 3-
Vinyl-based compounds having a hydrolyzable silyl group, such as (meth) acryloyloxypropyltri-n-propoxysilane, 3- (meth) acryloyloxypropyltriiso-propoxysilane, and 3- (meth) acryloyloxypropylmethyldichlorosilane. Monomer;

(25) 2-Trimethylsiloxyethyl (meth) acrylate, 2-trimethylsiloxypropyl (meth) acrylate, 4-trimethylsiloxybutyl (meth) acrylate, 2-triethylsiloxyethyl (meth) acrylate, 2-tributylsiloxy A vinyl monomer having a hydroxyl group blocked with a triorganosilyl group, such as propyl (meth) acrylate or 3-triphenylsiloxypropyl (meth) acrylate, 2-trimethylsiloxyethyl vinyl ether, 4-trimethylsiloxybutyl vinyl ether and the like. ;

(26) A silyl ester group such as trimethylsilyl (meth) acrylate, dimethyl-tert-butylsilyl (meth) acrylate, dimethylcyclohexylsilyl (meth) acrylate, trimethylsilyl crotonate, monovinyl-monotrimethylsilyl ester of adipic acid, etc. Vinyl-based monomer contained;

(27) 1-methoxyethyl (meth) acrylate, 1-ethoxyethyl (meth) acrylate,
A vinyl-based monomer having a hemiacetal ester group or a hemiketal ester group, such as 2-methoxy-2- (meth) acryloyloxypropane or 2- (meth) acryloyloxytetrahydrofuran;

(28) Glycidyl (meth) acrylate, methylglycidyl (meth) acrylate, 3,4-
Epoxy cyclohexyl (meth) acrylate, glycidyl vinyl ether, allyl glycidyl ether and other vinyl monomers containing an epoxy group;

(29) 2-isocyanatopropene, 2
-Isocyanatoethyl vinyl ether, 2-isocyanatoethyl methacrylate, m-isopropenyl-
a vinyl-based monomer containing an isocyanate group such as α, α-dimethylbenzyl isocyanate;

(30) Polyethylene glycol mono (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, and other vinyl monomers having various molecular weight (single-terminal alkylated) polyethylene glycol chains can be exemplified.

These monomers can be appropriately selected and used according to the desired final coating film performance. However, in the present invention, the epoxy resin (a) and the fatty acid (b) and, if necessary, the monobasic acid compound (e) are used as the amount of the mixture (d) of the vinyl compound containing these acid group-containing monomers. It is preferably 15 parts by weight or more based on 100 parts by weight of the total amount of the condensate (c) and the mixture (d) of the vinyl compound containing the acid group-containing monomer. Such a raw material ratio is determined in consideration of the balance between the corrosion resistance and the hardness of the resulting coating film. In the present invention, when the amount of the vinyl compound mixture (d) containing the acid group-containing monomer used is 15% or less, the desired balance between corrosion resistance and hardness is lacking.

The radical polymerization initiator used in the reaction of the vinyl compound mixture (d) containing the acid group-containing monomer is not particularly limited as long as it is a commonly used radical polymerization initiator. Of these, 2,2′-azobis (isobutyronitrile), 2,2′-azobis (2,4-dimethylbutyronitrile), and azobiscyanovaleric acid are specifically exemplified. Various azo compounds such as: tert-butylperoxypivalate, tert-butylperoxybenzoate, ter
Various organic peroxides such as t-butylperoxy-2-ethylhexanoate, di-tert-butylperoxide, cumene hydroperoxide, benzoyl peroxide, t-butyl hydroperoxide; hydrogen peroxide Water-soluble inorganic peroxides such as; and various inorganic peroxides such as persulfates such as ammonium persulfate, potassium persulfate, and sodium persulfate. Of course, these may be used alone or in combination of two or more kinds.

The amount of the radical polymerization initiator used is in the range of 0.1 to 10 parts by weight based on 100 parts by weight of the total amount of the monomers (mixture (d) of the vinyl compound containing the acid group-containing monomer). The inside is appropriate.

In order to control the molecular weight, the amount of the above-mentioned radical polymerization initiator, the reaction temperature, and further the chain transfer agent are used for adjustment. Examples of such chain transfer agents include n-octyl mercaptan, n-dodecyl mercaptan, t-
Alkyl mercaptans such as dodecyl mercaptan;
Examples thereof include aromatic mercaptans such as benzyl mercaptan and dodecylbenzyl mercaptan; thiocarboxylic acids such as thiomalic acid, salts thereof, alkyl esters thereof, and polythiols.

These are the amount of radical polymerization initiator used,
Although it depends on the reaction temperature, when a polymer having a relatively low molecular weight is obtained, it is preferably used in the range of 0.2 to 30% by weight based on the total monomers.

At the time of polymerization of the vinyl compound mixture (d) containing the acid group-containing monomer, an organic solvent may be used in combination for graft polymerization. When an organic solvent is used, the viscosity of the reaction product can be reduced, and the target product can be obtained uniformly and efficiently. The organic solvent used at that time is not particularly limited, and any general-purpose organic solvent can be used.

Of these, only typical ones are exemplified, and aliphatic or alicyclic hydrocarbons such as n-hexane, heptane, n-octane, cyclohexane and cyclopentane. Aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene; various esters such as ethyl acetate, n-butyl acetate, ethylene glycol monomethyl ether acetate; acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl n-amyl ketone , Various ketones such as cyclohexanone;

Diethylene glycol dimethyl ether,
Polyalkylene glycol dialkyl ethers such as diethylene glycol dibutyl ether; ethers such as 1,2-dimethoxyethane and tetrahydrofuran; N-methylpyrrolidone, dimethylformamide, dimethylacetamide, ethylene carbonate and the like, and further methanol, ethanol, propanol, Isopropanol, n-butanol, i-butanol, sec-
Butanol, tert-butanol, 3-methoxy-3
Alcohol-based organic solvents such as methylbutanol; halogen-containing organic solvents including freon-based solvents such as carbon tetrachloride, methylene dichloride, and hexafluoroisopropanol. Of these, dispersibility in water,
From the viewpoint of removing the solvent after being dispersed in water, it is preferable to use a hydrophilic solvent having solubility in water.

It is necessary to neutralize some or all of the acid groups in the vinyl-modified epoxy ester prior to water-solubilization. As the neutralizing agent used at that time, inorganic basic substances such as ammonia, lithium hydroxide, sodium hydroxide, and potassium hydroxide, methylamine, ethylamine, n-butylamine, dimethylamine, diethylamine, trimethylamine, triethylamine, Alkylamines such as tri-n-butylamine; hydroxylamines such as N-methylaminoethanol, N, N-dimethylaminoethanol, N, N-diethylaminoethanol, 2-amino-2-methylpropanol, diethanolamine and triethanolamine. Examples thereof include organic amines such as polyamines such as ethylenediamine and diethylenetriamine. Of these, the use of volatile basic compounds such as ammonia and organic amines is preferred.

The obtained vinyl-modified epoxy ester resin is made aqueous by neutralizing a part or all of the acid groups in the resin with the above-mentioned neutralizing agent, and then adding water, preferably ion-exchanged water. You can In the neutralization process,
The required neutralizing agent is continuously, batchwise or batchwise charged into the reaction vessel and mixed with the vinyl-modified epoxy ester resin with stirring. The temperature of the system can be neutralized by mixing from room temperature to the boiling point of the neutralizing agent or, if a solvent is also used, whichever is the lower boiling point, for about 30 minutes to several hours. Industrially, at temperatures below 100 ° C, 1-2
Mixing for about an hour is sufficient. After the completion of the neutralization step, water, preferably ion-exchanged water, is charged into the reaction vessel continuously, batchwise or all at once in the system, and phase inversion emulsification is performed while stirring.
The phase inversion emulsification can be carried out by mixing the temperature of the system from room temperature to the boiling point of the neutralizing agent or, if water or a solvent is used in combination, whichever is lower, for about 1 hour to several hours. It is industrially possible to mix at a temperature of 100 ° C. or lower for several hours. Thus, the aqueous dispersion of the vinyl-modified epoxy ester resin of the present invention can be prepared.

The aqueous dispersion of the vinyl-modified epoxy ester resin of the present invention can be used as a clear paint containing no pigment, or can be used as an aqueous paint composition containing pigments and the like as required. In addition, such an aqueous coating composition, if necessary, an additive suitable for various applications,
For example, various known additives such as a metal dryer, a filler, a leveling agent, a thickener, a defoaming agent, an organic solvent, an ultraviolet absorber, an antioxidant or a pigment dispersant may be added. Can be used.

Typical pigments include carbon
Black, phthalocyanine blue, phthalocyanine
Organic pigments such as green and quinacridone red;
Metal oxide type inorganic pigments such as titanium oxide, iron oxide, titanium yellow and copper chrome black; extender pigments such as calcium carbonate, clay, talc and barium sulfate.
Further, inorganic flake pigments such as aluminum flakes and pearl mica are listed. The amount of pigment used is usually 65% as a pigment weight concentration (PWC).
Used below. If it exceeds 65%, the resulting coating film tends to be porous, and as a result, the corrosion resistance tends to be poor.

A rust preventive pigment may be used as the pigment. When using anti-corrosion pigment, PWC is about 15%
It is preferable to use within the range. Even if it is used in excess of 15%, the effect of adding anticorrosion pigment will be saturated,
The resulting coating film tends to have poor water resistance, which is not desirable. Typical anticorrosion pigments include chromate compounds such as basic lead chromate, zinc chromate, strontium chromate, and barium chromate; lead-based compounds such as calcium leadate, lead tin, and lead cyanamide; zinc phosphate; Phosphate compounds such as aluminum tripolyphosphate and zinc phosphite; Molybdate compounds such as basic zinc molybdate and calcium molybdate; Barium metaborate; Borate compounds such as calcium metaborate and calcium borosilicate ; Mica-like iron oxide, general formula MeO
Fe2O3 (where Me is Ca, Sr, Ba,
It represents a divalent metal atom consisting of Mg, Zn and Mn. Examples thereof include iron oxide compounds such as magnetic ferrite; basic tungstate compounds such as zinc tungstate and calcium tungstate. These may be used alone or in combination of two or more kinds.

Typical metal dryers include cobalt naphthenate, lead naphthenate, zirconium naphthenate, manganese naphthenate, and calcium naphthenate. These 1 type, or 2 or more types can be mixed and used. The amount used is preferably about 0.05 to 5 parts by weight per 100 parts of the resin solid content.

In order to produce an aqueous coating composition, first, in the case of a clear coating composition, an aqueous vinyl-modified epoxy ester resin, various additives and water or a solvent for viscosity adjustment are added and mixed well. In the case of a water-based coating composition containing a pigment, the pigment is preliminarily dispersed and kneaded with a pigment-dispersing resin or an additive, and in some cases, the aqueous vinyl-modified epoxy ester resin of the present invention to prepare a pigment mill base. The aqueous vinyl-modified epoxy ester resin, various additives and water or a solvent for adjusting the viscosity may be added and mixed well.

The water-based coating composition of the present invention is thus obtained. In addition to the above components, various water-based resins described below can be used in combination. Typical of such water-based resins are vinyl acetate resins, styrene-
Butadiene-based resin, styrene-acrylonitrile-based resin, acrylic resin, fluoroolefin-based resin, silicon-modified vinyl-based polymer, vinyl-based polymer such as polyvinyl alcohol; polyester-based resin, polyurethane-based resin, phenol-based resin, melamine-based resin , Epoxy resins, alkyd resins, polyamide resins, polyether resins, silicone resins and other synthetic resins other than vinyl polymers; natural polymers such as animal protein, starch, cellulose derivatives, dextrin, and gum arabic Is mentioned. Of these, preferred are vinyl polymers and various synthetic resins other than vinyl polymers. It is preferable that these resins have an active hydrogen-containing group, and the form, type, etc. are not limited.

Typical examples of the ultraviolet absorber added in the preparation of the coating material used in the present invention include known and commonly used various compounds such as benzotriazole compounds, oxalic acid anilide compounds, and hydroxybenzophenone compounds. be able to. As the antioxidant to be added, known and commonly used compounds such as hindered amine compounds, hindered phenol compounds and phosphorus compounds can be used. And, when these are added, the addition amount is 100 parts by weight of the solid content of the aqueous coating composition,
UV absorber and / or antioxidant is preferably 0.2
The amount may be set to 10 to 10 parts by weight, more preferably 0.5 to 5 parts by weight.

The top coating composition thus obtained is coated on a substrate and then dried at room temperature for about 1 to 10 days, or at a temperature range of about 40 to about 250 ° C. for about 30 seconds to about 24 seconds. By heating for about a time, a cured coating film having high practicality is provided.

As the base material to which the water-based coating composition of the present invention is applied, various known and commonly used base materials are used. Among them, particularly typical ones are various metal base materials and inorganic base materials. Material, plastic base material, paper, wood base material,
Examples include natural fibers, synthetic fibers, natural leather, synthetic leather, artificial leather and the like.

Of the various base materials, typical metal base materials include iron, nickel, aluminum, copper,
Metals such as lead, chromium, zinc, tin; stainless steel,
Alloys of the above-mentioned metals such as brass; various metals or alloys as described above, and various surface-treated metals that have been plated or subjected to chemical conversion treatment.

The inorganic substrate is calcium silicate,
Hardened body made from calcium compounds such as calcium aluminate, calcium sulfate and calcium oxide; ceramics obtained by sintering metal oxides such as alumina, silica and zirconia; obtained by sintering various clay minerals Tiles; various types of glass and the like can be mentioned. Typical examples of hardened products produced from calcium compounds include hardened products of cement compositions such as concrete and mortar, asbestos slate, lightweight cellular concrete (AL
C) A hardened body, a dolomite plaster hardened body, a gypsum plaster hardened body, a calcium silicate board, etc. are mentioned.

Typical plastic substrates include polystyrene, polycarbonate, polymethylmethacrylate, ABS resin, polyphenylene oxide,
Molded products of thermoplastic resins such as polyurethane, polyethylene, polyvinyl chloride, polypropylene, polybutylene terephthalate, polyethylene terephthalate; unsaturated polyester resin, epoxy resin, phenol resin, cross-linked polyurethane, cross-linked acrylic resin, cross-linked saturated Examples include thermosetting resin molded products such as polyester resins.

Further, even if various kinds of base materials such as those mentioned above are coated and the deterioration of the coated portion is advanced, they are still used as the base material in the present invention. Can be used.

As the shape of such various base materials, various shapes such as a plate shape, a spherical shape, a film shape, a sheet shape, a large structure, and an assembly having a complicated shape can be used depending on the application. There is no particular limitation.

In order to form a cured coating film and obtain a coated article, a water-based coating material for top coating is applied to various substrates as described above by brush coating, roller coating, spray coating, dip coating, flow coater coating. The coating may be carried out by a known and commonly used coating method such as roll coating, electrodeposition coating, or the like, and then cured.

Then, the base material coated with the uncured top coating film is left at room temperature for about 1 to 10 days or about 4 times.
By heating in a temperature range of 0 to about 250 ° C. for about 30 seconds to 24 hours, a coated article coated with a cured coating film excellent in appearance and water resistance can be obtained.

As described above, a coated article coated with a cured coating film which is excellent in corrosion resistance, coating film hardness, particularly coating film hardness immediately after coating film formation can be obtained. Specific examples of such coated products include metal parts using a metal base material as a base material, automobiles, motorcycles, trains,
Transportation-related devices such as bicycles, ships, and airplanes; Metal- and plastic-based parts used in the above-mentioned transportation-related devices; TVs, radios, refrigerators, and washing machines in which metal or plastic is used as the substrate. , Coolers, cooler outdoor units, computers, home appliances and their parts;

Various building materials such as various types of inorganic roof tiles, metal roofing materials, inorganic outer wall materials, metal wall materials, metal window frames, metal or wood doors, wood inner wall materials Category: Outdoor structures such as roads, road signs, guardrails, bridges, tanks, chimneys, buildings; and various coating films coated on various organic films such as polyester resin film, acrylic resin film or fluororesin film Is mentioned. The coated article according to the present invention can be effectively used for such purposes.

[0093]

EXAMPLES The present invention will be described in detail with reference to Reference Examples, Examples and Comparative Examples, but the present invention is not limited thereto. All parts and% in the text are based on weight unless otherwise specified.

Example 1 [Preparation of Aqueous Dispersion of Vinyl-Modified Epoxy Ester Resin] In a four-necked flask equipped with a stirrer, a thermometer, a temperature control device, and a nitrogen inlet tube, dehydrated castor oil fatty acid of 150
Parts and 50 parts of soybean oil fatty acid, 500 parts of Epicoat 1001 (epoxy equivalent 475 g / mol), p-ter
60.2 parts of t-butylbenzoic acid was charged. In this raw material ratio, the ratio of the carboxyl group derived from fatty acid to the epoxy group derived from epoxy resin is excess epoxy group, and the excess epoxy group and the monobasic acid compound p-tert-
The amount is the same as that of the carboxyl group derived from butylbenzoic acid.

Furthermore, triethylamine of 0.1% was added to the reaction vessel.
Charge 02 parts and raise the temperature to 180 ° C. with stirring.
When the internal temperature reaches around 180 ° C., dehydration starts, and while watching the dehydrated state, the temperature is raised to 220 ° C. and esterification proceeds. The contents were reacted in about 3 hours until the solid content acid value was 1 or less. Then, the internal temperature was lowered to 150 ° C., and 253.4 parts of butyl cellosolve was added to obtain a 75% non-volatile solution of fatty acid ester of epoxy resin.

Next, the internal temperature was maintained at 125 ° C., and 120 parts of styrene, 49.8 parts of 2-ethylhexyl methacrylate, 40 parts of acrylic acid, and polyethylene glycol and methacryl having a molecular weight of 400 were placed in a reaction vessel. A mixture of 30 parts of a monoester compound with an acid, 5 parts of t-butylperoxy-2-ethylhexanoate and di-t.
3 parts of -butyl peroxy ether was added over 1 hour, and the mixture was further reacted at the same temperature for 10 hours to vinylate the fatty acid ester of the epoxy resin. Here, the vinyl compound is used in an amount of 100 total of the condensate (c) containing the epoxy resin and the fatty acid and the vinyl compound.
It is about 24% with respect to parts by weight. The obtained vinyl-modified epoxy ester resin was a viscous solution having a nonvolatile content of 80%, and the solid content acid value was 30 mgKOH / g.

Then, the reaction vessel was charged with triethylamine 54
g was added and mixed well, and 1550 g of ion-exchanged water was added little by little while stirring. With the addition of ion-exchanged water, the contents became a highly viscous white turbid substance, and with the addition of ion-exchanged water, a white emulsion was obtained. The resulting vinyl-modified epoxy ester resin aqueous dispersion had a solid content of 35.
%, An aqueous dispersion having a pH of 9.2. Hereinafter this water dispersion is referred to as A-1.

Example 2 [Preparation of Aqueous Dispersion of Vinyl Modified Epoxy Ester Resin] In a four-necked flask equipped with a stirrer, a thermometer, a temperature controller and a nitrogen introducing tube, 100 parts of linseed oil fatty acid and dehydration were added. 50 parts of castor oil fatty acid and Epicoat 1004
600 parts of (epoxy equivalent of 950 g / mol) and 17 parts of benzoic acid were charged. This raw material ratio is such that the ratio of the carboxyl group derived from the fatty acid and the epoxy group derived from the epoxy resin is in excess of the epoxy group, and the excess epoxy group and the carboxyl group derived from benzoic acid which is a monobasic acid compound are equal in amount. is there.

Further, 0.03 part of N, N-dimethylbenzylamine was charged into the reaction vessel and stirred at 180 ° C.
Up to. When the internal temperature reaches around 180 ° C., dehydration starts, and while watching the dehydrated state, the temperature is raised to 220 ° C. and esterification proceeds. The contents were reacted in about 3 hours until the solid content acid value was 1 or less. Then, set the internal temperature to 150 ° C.
The temperature was lowered to 328.7 parts of ethylene glycol isopropyl ether to obtain a 70% non-volatile solution of fatty acid ester of epoxy resin.

Next, the internal temperature was maintained at 125 ° C., and 70 parts of styrene, 70 parts of n-butyl methacrylate, 43 parts of n-butyl acrylate, 30 parts of acrylic acid and 30 parts of methacrylic acid were placed in a reaction vessel. 15 parts, a mixture of 5 parts of a monoester compound of polyethylene glycol and methacrylic acid having a molecular weight of 4000, 6 parts of t-butylperoxy-2-ethylhexanoate and 3 parts of di-t-butylperoxyether. Parts were added over 1 hour and further reacted at the same temperature for 10 hours to carry out vinylation reaction on the fatty acid ester of the epoxy resin.

Here, the amount of the vinyl compound used is about 23% with respect to 100 parts by weight of the total amount of the condensate (c) containing the epoxy resin and the fatty acid and the vinyl compound. The obtained vinyl-modified epoxy ester resin has a nonvolatile content of 7
It is a viscous solution of 5.3% and has a solid content acid value of 33.
It was mgKOH / g.

Next, add 59% triethylamine to the reaction vessel.
g was added and mixed well, and 1470 g of ion-exchanged water was added little by little while stirring. With the addition of ion-exchanged water, the contents became a highly viscous white turbid substance, and with the addition of ion-exchanged water, a white emulsion was obtained. The resulting vinyl-modified epoxy ester resin aqueous dispersion had a solid content of 35.
%, An aqueous dispersion having a pH of 9.2. Hereinafter this water dispersion is referred to as A-2.

Example 3 [Preparation of Aqueous Dispersion of Vinyl Modified Epoxy Ester Resin] In a four-necked flask equipped with a stirrer, a thermometer, a temperature controller, and a nitrogen introducing tube, 283 of dehydrated castor oil fatty acid was prepared.
And Epicoat 1001 (epoxy equivalent 475 g / m
ol) and 8 parts of cyclohexanecarboxylic acid were charged. In this raw material ratio, the ratio of the carboxyl group derived from the fatty acid to the epoxy group derived from the epoxy resin is an epoxy group excess, and the excess epoxy group and the carboxyl group derived from the cyclohexanecarboxylic acid, which is a monobasic acid compound, are equivalent. Is.

Further, 0.01 part of N, N-dimethylbenzylamine was charged in a reaction vessel and stirred at 180 ° C.
Up to. When the internal temperature reaches around 180 ° C., dehydration starts, and while watching the dehydrated state, the temperature is raised to 220 ° C. and esterification proceeds. The contents were reacted in about 3 hours until the solid content acid value was 1 or less. Then, set the internal temperature to 150 ° C.
The temperature was lowered to 266.7 parts of propylene glycol-n-propyl ether, and a 75% non-volatile solution of fatty acid ester of epoxy resin was obtained.

Next, the internal temperature was maintained at 125 ° C., and 55 parts of styrene, 70 parts of i-butyl methacrylate, 25 parts of 2-ethylhexyl acrylate were placed in a reaction vessel.
A mixture of 45 parts of acrylic acid, 5 parts of a monoester compound of polyethylene glycol and methacrylic acid having a molecular weight of 1000, 4 parts of t-butylperoxy-2-ethylhexanoate and di-t-butylperoxy. 2 parts of ether was added over 1 hour and 10 parts at the same temperature was added.
The reaction was carried out for a period of time, and the fatty acid ester of the epoxy resin was vinylated.

The amount of the vinyl compound used is about 20% based on 100 parts by weight of the total amount of the vinyl compound and the condensate (c) containing the epoxy resin and the fatty acid. The resulting vinyl-modified epoxy ester resin has a nonvolatile content of 79
% Viscous solution with a solid content acid value of 35 mgK
It was OH / g.

Next, the reaction vessel was charged with 63% of triethylamine.
g was added and mixed well, and 1528 g of ion-exchanged water was added little by little while stirring. With the addition of ion-exchanged water, the contents became a highly viscous white turbid substance, and with the addition of ion-exchanged water, a white emulsion was obtained. The resulting vinyl-modified epoxy ester resin aqueous dispersion had a solid content of 35.
%, An aqueous dispersion having a pH of 9.4. Hereinafter this water dispersion is referred to as A-3.

Example 4 [Preparation of Aqueous Dispersion of Vinyl-Modified Epoxy Ester Resin] In a four-necked flask equipped with a stirrer, a thermometer, a temperature controller, and a nitrogen introducing tube, dehydrated castor oil fatty acid 283 was prepared.
And Epicoat 1001 (epoxy equivalent 475 g / m
ol) and 8 parts of cyclohexanecarboxylic acid were charged. In this raw material ratio, the ratio of the carboxyl group derived from the fatty acid to the epoxy group derived from the epoxy resin is an epoxy group excess, and the excess epoxy group and the carboxyl group derived from the cyclohexanecarboxylic acid, which is a monobasic acid compound, are equivalent. Is.

Further, 0.01 part of N, N-dimethylbenzylamine was charged into the reaction vessel and stirred at 180 ° C.
Up to. When the internal temperature reaches around 180 ° C., dehydration starts, and while watching the dehydrated state, the temperature is raised to 220 ° C. and esterification proceeds. The contents were reacted in about 3 hours until the solid content acid value was 1 or less. Then, set the internal temperature to 150 ° C.
The temperature was lowered to 266.7 parts of propylene glycol-n-propyl ether, and a 75% non-volatile solution of fatty acid ester of epoxy resin was obtained.

Next, the internal temperature was maintained at 125 ° C., and 55 parts of styrene, 70 parts of i-butyl methacrylate, 25 parts of 2-ethylhexyl acrylate were placed in a reaction vessel.
A mixture of 45 parts of acrylic acid, 5 parts of a monoester compound of polyethylene glycol and methacrylic acid having a molecular weight of 1000, 4 parts of t-butylperoxy-2-ethylhexanoate and di-t-butylperoxy. 2 parts of ether was added over 1 hour and 10 parts at the same temperature was added.
The reaction was carried out for a period of time, and the fatty acid ester of the epoxy resin was vinylated.

Here, the amount of the vinyl compound used is about 20% based on 100 parts by weight of the total amount of the vinyl compound and the condensate (c) containing the epoxy resin and the fatty acid. The resulting vinyl-modified epoxy ester resin has a nonvolatile content of 79
% Viscous solution with a solid content acid value of 35 mgK
It was OH / g.

Then, add 63% of triethylamine to the reaction vessel.
g was added and mixed well, and 1528 g of ion-exchanged water was added little by little while stirring. With the addition of ion-exchanged water, the contents became a highly viscous white turbid substance, and with the addition of ion-exchanged water, a white emulsion was obtained. The resulting vinyl-modified epoxy ester resin aqueous dispersion had a solid content of 35.
%, An aqueous dispersion having a pH of 9.4. Hereinafter this water dispersion is referred to as A-4.

Comparative Example 5 [Preparation of Aqueous Dispersion of Vinyl-Modified Epoxy Ester Resin for Comparison] A four-necked flask equipped with a stirrer, a thermometer, a temperature controller, and a nitrogen introduction tube was charged with dehydrated castor oil fatty acid. 100
And 100 parts of flaxseed oil fatty acid, 200 parts of safflower oil fatty acid, Epicoat 1001 (epoxy equivalent 475
(g / mol) 450 parts, and Epicoat 1004 (epoxy equivalent 950 g / mol) 80 parts were charged. In this raw material ratio, the ratio of a carboxyl group derived from a fatty acid and an epoxy group derived from an epoxy resin is in excess of a carboxyl group.

Further, 0.05 part of N, N-dimethylbenzylamine was charged into the reaction vessel and stirred at 180 ° C.
Up to. When the internal temperature reaches around 180 ° C., dehydration starts, and while watching the dehydrated state, the temperature is raised to 220 ° C. and esterification proceeds. The contents were reacted in about 3 hours until the solid content acid value became 4. Then, the internal temperature was lowered to 175 ° C., and 5 parts of maleic anhydride and 5 parts of trimellitic anhydride were added to carry out a reaction to bring the acid value to 9. Furthermore, 403 parts of butyl cellosolve was added to obtain a 70% non-volatile solution of fatty acid ester of epoxy resin.

Then, the internal temperature was maintained at 120 ° C., and a mixture of 30 parts of styrene, 15 parts of acrylic acid and 15 parts of methacrylic acid and t-butylperoxy-2- was placed in a reaction vessel.
Add 5 parts of ethyl hexanoate dropwise over 1 hour and
5 parts of -t-butyl peroxy ether was added, and the temperature was kept at the same temperature for 10 hours to carry out a vinylation reaction on the fatty acid ester of the epoxy resin.

The amount of the vinyl compound used is about 6% based on 100 parts by weight of the total amount of the vinyl compound and the condensate (c) containing the epoxy resin and the fatty acid. The vinyl-modified epoxy ester resin obtained has a nonvolatile content of 71%.
Is a viscous solution with a solid content acid value of 27 mg KO
It was H / g.

Then, the reaction vessel was charged with triethylamine 4
8.6 g was added and mixed well, and 1048 g of ion-exchanged water was added little by little while stirring. With the addition of ion-exchanged water, the contents became a highly viscous white turbid substance, and with the addition of ion-exchanged water, a white emulsion was obtained. The obtained water dispersion of vinyl-modified epoxy ester resin was a water dispersion having a solid content of 40% and a pH of 9.2. Hereinafter this water dispersion is referred to as R-1.

Comparative Example 6 [Preparation of Aqueous Dispersion of Vinyl-Modified Epoxy Ester Resin for Comparison] A four-necked flask equipped with a stirrer, a thermometer, a temperature controller, and a nitrogen inlet tube was charged with linseed oil fatty acid. 500 copies,
4 of Epicoat 1001 (epoxy equivalent 475 g / mol)
I prepared 20 copies. In this raw material ratio, the ratio of a carboxyl group derived from a fatty acid and an epoxy group derived from an epoxy resin is in excess of epoxy groups.

Further, 0.05 part of N, N-dimethylbenzylamine was charged in a reaction vessel and stirred at 180 ° C.
Up to. When the internal temperature reaches around 180 ° C., dehydration starts, and while watching the dehydrated state, the temperature is raised to 220 ° C. and esterification proceeds. The contents were reacted for about 3 hours until the solid content acid value became 6. Next, the internal temperature was lowered to 150 ° C., 394 parts of butyl cellosolve was added, and a 70% non-volatile solution of fatty acid ester of epoxy resin was obtained.

Next, the internal temperature was maintained at 120 ° C., and a mixture of 40 parts of styrene, 30 parts of acrylic acid and 10 parts of itaconic acid and 5 parts of di-t-butylperoxyether were placed in a reaction vessel. 1 part was added dropwise over 1 hour, 3 parts of t-butylperoxy-2-ethylhexanoate and 3 parts of di-t-butylperoxyether were added, and the mixture was kept at the same temperature for 5 hours to obtain an epoxy resin. Vinylation reaction was performed on the fatty acid ester of the resin.

The amount of the vinyl compound used is about 8% based on 100 parts by weight of the total amount of the vinyl compound and the condensate (c) containing the epoxy resin and the fatty acid. The vinyl-modified epoxy ester resin obtained has a nonvolatile content of 72%.
Is a viscous solution with a solid content acid value of 32 mg KO
It was H / g.

Next, 5% of triethylamine was added to the reaction vessel.
7.6 g was added and mixed well, and 1048 g of ion-exchanged water was added little by little while stirring. With the addition of ion-exchanged water, the contents became a highly viscous white turbid substance, and with the addition of ion-exchanged water, a white emulsion was obtained. The resulting water dispersion of vinyl-modified epoxy ester resin was a water dispersion having a solid content of 40% and a pH of 9.3. Hereinafter this water dispersion is referred to as R-2.

Application Examples 1 to 4 and Comparative Application Examples 1 to 2 The water dispersions obtained in Examples and Comparative Examples were made into paints with the formulations shown in Table 1 to prepare water-based paints.

[0124]

[Table 1]

(1) Aqueous paints were prepared by mixing the above A to G, dispersing them in a sand mill for 1 hour, and then adding H to J. A small amount of K was added at the time of coating. (2) Carbon black is MA-1 from Mitsubishi Kasei.
00 was used. (3) As the calcium carbonate 1, homocal D manufactured by Shiraishi Sangyo Co., Ltd. was used. (4) Calcium carbonate 2 is NS-Nitto Kouka Co., Ltd.
100 was used. (5) As the rust preventive pigment, a zinc phosphate-based rust preventive pigment manufactured by Kikuchi Dye Co., Ltd. was used. (6) The defoamer is BYK-made by Germany
K-080 was used. (7) Dick Nate 3111 is an aqueous metal dryer manufactured by Dainippon Ink and Chemicals, Inc. (8) High Cure MIX is a dryer manufactured by Toei Kako Co., Ltd. (9) Active dryer T is a dryer activator manufactured by Toei Kako Co., Ltd.

Thereafter, each of the obtained paints was
An untreated dull steel plate that had been degreased with toluene was coated so that the dry film thickness was 30 μm, and dried under predetermined conditions to prepare a coated plate for a test. Next, various coating film performance evaluations were performed. The results are shown in Table 2.

[0127]

[Table 2]

Drying at room temperature: After coating, it was left at room temperature for 10 days. Forced drying: After coating, it was dried for 20 minutes in an atmosphere of 70 ° C. and left at room temperature for 5 days.

Water resistance: After predetermined drying, the coated plate was immersed in tap water for 10 days, and then its appearance was evaluated. ⊚: No abnormality is found on the coating film. ◯: Slight swelling is observed in the coating film. B: Swelling is observed in the coating film. X: The coating film is swollen and peeled off.

Initial hardness: In the case of drying at room temperature, the pencil hardness was evaluated one day after coating. For forced drying, paint 7
The pencil hardness was evaluated immediately after drying at 0 ° C. for 20 minutes.

SS properties: Salt spray test at 35 ° C.
A razor is used to put a cross-cut on the coated plate, a test is performed for a predetermined period of time, and then the cross-cut portion is taken out and a peeling test is performed using Cellotape (registered trademark). ⊚: The peel width in the peel test is 1 mm or less, which is extremely excellent in corrosion resistance. ◯: The peeling width in the peeling test is 1 to 2 mm. (Triangle | delta): The peeling width of a peeling test is 2-3 mm. X: The peel width in the peel test is 3 mm or more, and the rust is remarkably generated.

[0132]

From the above results, the aqueous paint using the aqueous dispersion of the present invention can form a coating film under various drying conditions such as room temperature drying and forced drying, and is excellent in any case. Further, it is possible to form a coating film having rust prevention power and high hardness immediately after the coating film is formed.

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) C09D 163/00 C09D 163/00 F Term (Reference) 4J036 AA01 AD01 AF01 AJ05 AJ08 AK03 CA21 JA01 4J038 CP101 CP121 DB301 DD091 GA01 KA08 MA08 MA10 NA03 NA11 PB05 PB07 PC01 PC02 PC06 PC08 PC09 PC10

Claims (6)

[Claims] 1. A vinyl compound containing an acid group-containing monomer capable of reacting with an epoxy resin (a) and a fatty acid (b) in the presence of a condensate (c) obtained by condensing the same as essential components. An aqueous dispersion of a vinyl-modified epoxy ester resin, which is obtained by graft-polymerizing the mixture (d), neutralizing at least a part of the acid groups in the resulting graft polymer, and then dispersing the mixture in water. The equivalent ratio of the epoxy group derived from OH to the carboxyl group derived from fatty acid is in excess of epoxy group, and the amount of the mixture (d) used is 100 parts by weight of the total amount of the condensate (c) and the mixture (d).
An aqueous dispersion of a vinyl-modified epoxy ester resin, which is 15 parts by weight or more. 2. Containing an acid group capable of reacting with an epoxy resin (a), a fatty acid (b) and a monobasic acid compound (e) in the presence of a condensate (c) obtained by condensing them as essential components. After graft-polymerizing the mixture (d) of vinyl compounds containing monomers to neutralize at least a part of the acid groups in the obtained graft polymer, water of the vinyl-modified epoxy ester resin dispersed in water. In the dispersion, the ratio of the epoxy groups derived from the epoxy resin and the carboxyl groups derived from the fatty acid is in excess of the epoxy groups, and the amount of the mixture (d) used is that of the condensate (c) and the mixture (d). An aqueous dispersion of a vinyl-modified epoxy ester resin, which is 15 parts by weight or more based on 100 parts by weight in total. 3. A mixture (d) of vinyl compounds containing an acid group-containing monomer comprises an aromatic vinyl compound, a (meth) acrylic acid alkyl ester having an alkyl group having 4 or more carbon atoms, and an acid group-containing vinyl compound. An aqueous dispersion of the vinyl-modified epoxy ester resin according to claim 1 or 2, which contains the same. 4. An aqueous coating composition comprising an aqueous dispersion of the vinyl-modified epoxy ester resin according to claim 1, 2 or 3 and a pigment. 5. The aqueous coating composition according to claim 4, wherein the pigment contains a rust preventive pigment. 6. A coated article coated with the aqueous coating composition according to claim 4 or 5.