JPH09296023A - Aqueous resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the properties of the active carbonyl-groupcontaining resin component of an aqueous resin dispersion that utilizes the crosslinking hardening mechanism of a hydrazine derivative and an active carbonyl-group- containing resin component and whose initial drying property (hardness in the initial stage of drying), corrosion resistance, water resistance, etc., are still unsatisfactory. SOLUTION: This composition is an aqueous resin composition comprising an active carbonyl group-containing acrylic monomermodified epoxy ester that is dispersed in water and is obtained by reacting at least the below-mentioned essential raw materials (1) to (3) in an arbitrary order: (1) a bisphenolic epoxy resin, (2) an unsaturated fatty acid, and (3) a monomer component containing essentially an active carbonyl group-containing (meth)acrylic monomer derived from a keto group or an aldehyde group and a carboxyl groupcontaining(meth) acrylic monomer.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an aqueous resin composition having an active carbonyl group, and more specifically, it can be used as a one-pack composition in combination with a hydrazine derivative, is excellent in storage stability, and has excellent storage stability after coating. A water-based resin that can easily undergo a crosslinking reaction at room temperature to form a cured coating film that has excellent adhesion to metal substrates, corrosion resistance, water resistance, and dryness, and that also has excellent hardness at the initial stage of drying and hardness after complete curing. It relates to a composition.

[0002]

2. Description of the Related Art Aqueous (water-soluble or water-dispersible) resin compositions used for paints are, for example, unsaturated polyester resin type, alkyd resin type, vinyl ester resin type, acrylic resin type, polyurethane resin type. Various types of compositions such as epoxy resin type and modified / mixed types of these have been developed. However, these conventional aqueous resin compositions are inferior in water resistance and corrosion resistance due to a means for forming an aqueous dispersion (use of an emulsifier and alkali neutralization), and in the case of a one-pack type composition, storage stability and Due to problems such as difficulty in balancing the hardness in the initial stage of drying, an aqueous resin composition that exhibits excellent performances on all aspects has not yet been obtained.

On the other hand, a composition is known in which a hydrazine derivative having two or more hydrazino groups in the molecule and an aqueous resin having an active carbonyl group are combined. This composition does not proceed in the presence of water, but since water evaporates after the coating film is formed, the crosslinking reaction between the hydrazino group and the active carbonyl group proceeds even at room temperature. It is used as an aqueous resin composition.

Various studies have been conducted on an aqueous resin having an active carbonyl group as a reaction partner of a hydrazine derivative, but an acrylic resin emulsion prepared by copolymerizing a monomer having an active carbonyl group is mainly used. Has been done. For example, JP-A-5-148406 discloses an example in which a low-molecular active carbonyl group-containing compound is present in a composition to block a hydrazine derivative to improve storage stability, and JP-A-5-98071. Describes an example in which an alkali and / or a polar organic solvent is added to the composition to improve the adhesion to the substrate and the water resistance. However, these acrylic resin emulsion and hydrazine derivative compositions still have room for improvement in properties such as storage stability, hardness in the initial stage of drying, corrosion resistance, water resistance, and adhesion.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides an aqueous resin dispersion utilizing a crosslinking and curing mechanism of a hydrazine derivative and an active carbonyl group, which still has insufficient initial drying property (hardness at the initial stage of drying), corrosion resistance and water resistance. In order to improve the above, it is an object to improve the properties of the active carbonyl group-containing resin component.

[0006]

The aqueous resin composition of the present invention which has solved the above-mentioned problems is (A) at least the following essential raw materials (1) to (3) (1) bisphenol type epoxy resin, (2) Reaction of a monomer component essentially containing an unsaturated fatty acid, (3) an active carbonyl group-containing (meth) acrylic monomer derived from a keto group or an aldehyde group and a carboxyl group-containing (meth) acrylic monomer in any order. The gist is that the active carbonyl group-containing acryl-modified epoxy ester obtained by is dispersed in water.

The aqueous resin composition of the present invention has the above (A)
In addition to the components, those in which (B) a hydrazine derivative having at least two hydrazino groups are dissolved or dispersed in the molecule are included, which are used when the composition is actually used as a film-forming composition. It is a mode.

The active carbonyl group-containing acryl-modified epoxy ester of (A) above is produced by reacting the bisphenol type epoxy resin of (1) with the unsaturated fatty acid of (2) and then the reaction of (1) and (2). By polymerizing a monomer component essentially containing an active carbonyl group-containing (meth) acrylic monomer derived from a keto group or an aldehyde group and a carboxyl group-containing (meth) acrylic monomer in the presence of a substance. What you get
The unsaturated fatty acid of (2) and the monomer component of (3) that essentially contains an active carbonyl group-containing (meth) acrylic monomer derived from a keto group or an aldehyde group and a carboxyl group-containing (meth) acrylic monomer. It is preferably obtained by reacting the bisphenol type epoxy resin (1) after polymerization.
The aqueous resin composition of the present invention is most suitable for use as a one-pack type paint.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION First, each constituent component of the aqueous resin composition of the present invention will be described. (A) Active Carbonyl Group-Containing Acrylic Modified Epoxy Ester (A) The active carbonyl group-containing acryl modified epoxy ester becomes a partner of the below-mentioned (B) hydrazine derivative cross-linking reaction and exerts a great influence on coating film physical properties. It is a resin component used for improving the initial drying property, corrosion resistance, and water resistance, which are the subjects of the present invention. This (A) is composed of the following three kinds of essential raw materials (1) to (3)
It is produced by reacting in any order.

(1) Bisphenol type epoxy resin The bisphenol type epoxy resin is an essential component for improving the corrosion resistance and chemical resistance of the coating film, and further improving the adhesion to metal. Moreover, since the terminal epoxy group of the bisphenol type epoxy resin has reactivity with the carboxyl group of (2) or (3) described later, it becomes a grafting point with (2) and (3), (A) is
(1), (2), and (3) are combined to form a high molecular weight composite resin.

As a specific example of (1), a known epoxy resin having two epoxy groups in one molecule, for example, bisphenol A type, tetrabromobisphenol A type,
Examples of the epoxy resin include bisphenol S type, bisphenol F type, and bisphenol AD type.
A mixture of more than one species can be used. The preferred epoxy equivalent is 150 to 3000, and the molecular weight is 300 to 400.
0.

(2) Unsaturated Fatty Acid The unsaturated fatty acid has an unsaturated double bond in its molecule as a graft reaction point with the following (3) or styrene used as necessary, or is an unsaturated diester. It is used as an essential component for the purpose of cross-linking curing by oxidative polymerization after forming a coating while leaving a heavy bond in (A), and the epoxy group of the epoxy resin of (1) above,
It is incorporated into (A) by the reaction of (2) with the carboxyl group or the reaction of (2) with the carboxyl group in the reaction product of (3). Unsaturated fatty acids have the effect of imparting durability and flexibility to the coating film and enhancing the dispersibility of the pigment. A glycerin ester of the unsaturated fatty acid, that is, a so-called drying oil may be used together with the unsaturated fatty acid, and two or more kinds of these may be mixed and used alone. Specific examples of (2) include dry oils such as flaxseed oil, tung oil, dehydrated castor oil, soybean oil, rice oil, safflower oil, sunflower oil, rapeseed oil and polymerized oil, and fatty acids thereof.

(3) Monomer component essentially containing an active carbonyl group-containing (meth) acrylic monomer and a carboxyl group-containing (meth) acrylic monomer derived from a keto group or an aldehyde group. The active carbonyl group-containing acrylic modified epoxy ester must essentially have an active carbonyl group in order to secure a reaction site with the hydrazino group. The use of a carboxyl group is also a necessary condition, considering the water-solubility and storage stability of the paint.
Therefore, in the present invention, as the third raw material, a monomer component having an active carbonyl group-containing (meth) acrylic monomer derived from a keto group or an aldehyde group and a carboxyl group-containing (meth) acrylic monomer as essential components can be polymerized. Amount, must be used. By polymerizing this (3), a (meth) acrylic polymer portion having an active carbonyl group and a carboxyl group is introduced into (A).

In order to polymerize (3), it is preferable to carry out graft polymerization on the unsaturated double bond contained in (2). Therefore, in order to polymerize (3), (1) and (2)
It is preferable to employ means for polymerizing (3) in the presence of this reaction product after reacting with, or for polymerizing (2) and (3) before the reaction with (1). At this time,
Since it may be difficult for (2) and (3) to directly react with each other, it is preferable to add an aromatic vinyl monomer such as styrene and perform copolymerization regardless of which method is adopted. Also, adding styrene or the like can be obtained (A)
It is also effective for improving the appearance of the coating film and improving properties such as quick-drying property and hardness.

The active carbonyl group-containing (meth) acrylic monomer is a compound having at least one active carbonyl group based on a keto group or an aldehyde group in the molecule and a (meth) acryloyl group. Diacetone (meth) acrylamide, (meth) acrolein,
Diacetone (meth) acrylate, acetonitrile (meth) acrylate, 2-hydroxypropyl (meth) acrylate acetyl acetate, butanediol-1,
4- (meth) acrylate acetyl acetate, (meth) acryloxyalkyl propenal, and the like. What is a carboxyl group-containing (meth) acrylic monomer?
Examples thereof include (meth) acrylic acid, itaconic acid, maleic acid, and their anhydrides, salts, monoesters, and the like.

In addition to the above essential monomer components, those usable as the monomer component (3) include aromatic vinyl monomers such as styrene described above (vinyltoluene, α-).
Methyl styrene, chlorostyrene, styrene sulfonic acid, etc.), methyl (meth) acrylate, ethyl (meth) acrylate, t-butyl (meth) acrylate,
n-butyl (meth) acrylate, iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, iso-
Octyl (meth) acrylate, cyclohexyl (meth) acrylate, t-butylcyclohexyl (meth)
(Meth) acrylic acid alkyl ester such as acrylate and lauryl (meth) acrylate; (meth) acrylic acid hydroxyalkyl ester such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate; (meth) acrylamide, N, N- (Meth) acrylamide derivatives such as dimethyl (meth) acrylamide; vinyl acetate, vinyl propionate, etc .; (meth)
Examples thereof include acrylonitrile and the like; vinyl ethers such as ethyl vinyl ether; basic monomers such as vinyl pyridine.

The preferred amount of each monomer used in (3) is 2.5 to 15.0% by weight of the active carbonyl-containing (meth) acrylic monomer, and 5% of the carboxyl group-containing (meth) acrylic monomer. 0.0 to 12.0% by weight, the other monomer is 73.0 to 92.5% by weight, and styrene is preferably used as the other monomer in 10 to 45% by weight.

The aqueous resin composition of the present invention has the above (1)
The active carbonyl group-containing acryl-modified epoxy ester (A) obtained by reacting the raw materials (1) to (3) in any order is an essential component. An example of the manufacturing method of (A) is shown below.

Production Method Example-1 [(A) in Claim 3] First, the bisphenol type epoxy resin of (1) and (2)
To produce an epoxy ester. At this time, the usage amount of (1) and (2) is (1) 10
It is preferable to add 30 to 70 parts by weight of (2) to 0 parts by weight (hereinafter simply referred to as "parts"). The reaction conditions are as follows: in the presence or absence of a solvent described below, in the presence of a catalyst such as a tertiary amine, a tertiary phosphine, or a quaternary ammonium salt.
It is good to carry out at -150 ° C.

Then, the monomer component of (3) is polymerized in the presence of the obtained reaction product of (1) and (2): epoxy ester. Reaction product of (1) and (2): 3 parts of the monomer component of (3) with respect to 100 parts of epoxy ester.
It is recommended to react 0 to 60 parts. The polymerization of (3) is preferably carried out in the presence of a solvent, and a known radical polymerization initiator such as a peroxide type or an azo type is used as a polymerization initiator in an amount of about 0.1 to 10% by weight based on the total amount of the monomers. It may be used at room temperature to about 200 ° C. When the polymerization is completed, the active carbonyl group-containing acrylic modified epoxy ester of (A) is produced. To obtain (A) as an aqueous dispersion, the solvent is partially or wholly distilled off if necessary, and then water and a basic compound are added to remove some or all of the carboxyl groups in (A). A method of neutralizing can be adopted. As the base compound, ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, dimethyl-n-propylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, dimethylaminoethylmethacrylate, polyethylene Imine, N-aminoethylethanolamine, N-methyldiethanolamine, monoisopropanolamine, diisopropanolamine,
Water-soluble and volatile amine compounds such as triisopropanolamine can be preferably used.

Production Method Example-2 [(A) in Claim 4] In the second method, first, (2) and (3) are polymerized to obtain an acid-modified active carbonyl group-containing acrylic resin. The amount of use of (2) and (3) is (3) 8 for 100 copies of (2).
0 to 300 parts, 10 to 45 styrene in (3)
It is more preferable to use the weight percent. The polymerization conditions are the same as the conditions described in Production Method Example-1. Then, the obtained reaction product of (2) and (3): the acid-modified active carbonyl group-containing acrylic resin is reacted with the bisphenol epoxy resin of (1). The amount of (1) used at this time is 20 to 20 relative to the reaction product of (2) and (3): 100 parts of the acid-modified active carbonyl group-containing acrylic resin.
It is preferably 0 part, and the reaction condition is 50 to 15 in the presence or absence of a solvent described below, in the presence of a catalyst such as a tertiary amine, a tertiary phosphine, or a quaternary ammonium salt.
It is good to carry out at 0 ° C. The water dispersion method is as described in the manufacturing method example-1.

In the above two methods, compounds usable as a solvent are hydrocarbons such as toluene and xylene;
Cellosolves such as cellosolve and butyl cellosolve; carbitols such as carbitol and butyl carbitol; esters such as cellosolve acetate and carbitol acetate; ketones such as methyl isobutyl ketone and methyl ethyl ketone; ethers such as diethylene glycol dimethyl ether A relatively hydrophilic cellosolve or the like is preferably used.

(B) Hydrazine derivative having two or more hydrazino groups in the molecule In the aqueous resin composition of the present invention, ₂ hydrazino groups (-NHNH ₂ ) for crosslinking reaction with the above-mentioned (A) are contained. Incorporating a hydrazine derivative (B) having more than one,
You may set it as a one-pack type composition. Specifically, saturated dicarboxylic acid dihydrazides such as oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, pimelic acid dihydrazide, suberic acid dihydrazide, azelaic acid dihydrazide, sebacic acid dihydrazide; Unsaturated dicarboxylic acid dihydrazides such as dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide; ethylene-1,2-dihydrazine, propylene-1,3-
Aliphatic water-soluble dihydrazines such as dihydrazine and butylene-1,4-dihydrazine; and oligomers or polymers having two or more hydrazino groups. Of these, adipic acid dihydrazide is preferably used in terms of storage stability.

The hydrazine derivative of (B) is (A)
It is preferable to mix 2.5 to 15 parts with respect to 100 parts of the active carbonyl group-containing acrylic modified epoxy ester.

In the aqueous resin composition of the present invention, if necessary, extender pigments such as talc, clay and barium sulfate, lead-based, chromium-based, zinc-based, phosphoric acid-based, molybdic acid-based, boric acid Anti-corrosion pigments, pigments for coloring, defoaming agents, coupling agents, surface modifiers, viscosity modifiers, UV absorbers, etc.
You may mix | blend a stabilizer, a crosslinking agent, etc. and the additive etc. which are commonly used in the coating field.

The aqueous resin composition of the present invention has excellent storage stability even when stored in a one-pack type in which (A) and (B) are mixed, and when cured, it can be rapidly cured at a relatively low temperature. Form a cured coating film. By using the characteristic (A) of the present invention, the obtained coating film is superior to the conventional one in hardness at the initial stage of drying, and exhibits good corrosion resistance, water resistance and adhesion. Further, it is also excellent in properties such as hardness, gloss, and appearance of coating film after completely cured. Therefore, as a one-component composition for forming a coating film, any coating method such as dip coating, spray coating, brush coating, roll coating, die coating and the like can be adopted.

[0027]

The present invention will be described in more detail with reference to the following examples, but the following examples do not limit the present invention.
Modifications and alterations that do not depart from the spirit described below are all included in the technical scope of the present invention. The parts and percentages in the examples are on a weight basis.

Example 1 As a reaction raw material for the first stage, a four-necked flask equipped with a stirrer, a thermometer, a condenser, a dropping funnel and a nitrogen gas introducing tube was placed in 250 parts of dehydrated castor oil fatty acid and Epicoat 1004.
[Bisphenol A type epoxy resin, manufactured by Yuka Shell Epoxy Co., Ltd.] 350 parts, Epicoat 828 [bisphenol A type epoxy resin, manufactured by Yuka Shell Epoxy Co., Ltd.]
100 parts, butyl cellosolve 250 parts and triethylamine 1.5 parts were charged, the temperature was raised to 140 ° C. while blowing nitrogen gas, and the reaction was allowed to proceed for 2 hours. When the acid value became 1 or less, the reaction was terminated and the epoxy ester was removed. Obtained. This reaction product is designated as a-1.

In this reaction product, as a second stage reaction raw material, 25 parts of diacetone acrylamide and 50 parts of acrylic acid were used.
Parts, 175 parts of styrene, 50 parts of methyl methacrylate, and perbutyl D [polymerization initiator: manufactured by NOF Corporation] 6
Part of the mixture was added dropwise from the dropping funnel over 2 hours, and the mixture was kept at 140 ° C. for 4 hours, then cooled to 80 ° C., 50 parts of triethylamine and 11 parts of deionized water were added.
93 parts were added to obtain an aqueous dispersion of acrylic modified epoxy ester (nonvolatile content: 40.0%, viscosity: 1000 mPas).
・ S). This is designated as A-1.

Example 2 The reaction product a-1 obtained in Example 1 was mixed with 50 parts of diacetone acrylamide, 50 parts of acrylic acid and 150 parts of styrene.
Aqueous dispersion A-2 was obtained in the same manner as in Example 1 except that a mixture of 1 part, 50 parts of methyl methacrylate, and 6 parts of perbutyl D was reacted (nonvolatile content 40.0%, viscosity 1000 mPa · S). .

Example 3 The reaction product a-1 obtained in Example 1 was mixed with 100 parts of diacetone acrylamide, 50 parts of acrylic acid and 100 parts of styrene.
Aqueous dispersion A-3 was obtained in the same manner as in Example 1 except that a mixture of 1 part, 50 parts of methyl methacrylate and 6 parts of perbutyl D was reacted (nonvolatile content: 40.0%, viscosity: 1000 mPa · S). .

Example 4 A flask similar to that of Example 1 was charged with 250 parts of dehydrated castor oil fatty acid and 250 parts of butyl cellosolve as a solvent as a first stage reaction raw material, and while blowing nitrogen gas, 14
The temperature was raised to 0 ° C., and a mixture of 50 parts of diacetone acrylamide, 50 parts of acrylic acid, 150 parts of styrene, 50 parts of methyl methacrylate and 6 parts of perbutyl D was added dropwise from a dropping funnel over 2 hours, and further 140
The temperature was maintained at 4 ° C for 4 hours to obtain an oil-modified acrylic resin.

Subsequently, the reaction mixture was charged with 350 parts of Epicoat 1004, 100 parts of Epicoat 828 and 2 parts of triethylamine as a second stage reaction raw material, and 1
After holding at 40 ° C. for 2 hours, it was cooled to 80 ° C. and 50 parts of triethylamine and 1192 parts of deionized water were added to obtain an aqueous dispersion A-4 (nonvolatile matter 40.0%, viscosity 1000 mPa · S). .

Example 5 In a flask similar to that of Example 1, 200 parts of dehydrated castor oil and butyl cellosolve 2 as a solvent were used as the first stage reaction raw materials.
50 parts were charged, the temperature was raised to 140 ° C. while blowing nitrogen gas, and a mixture of 50 parts diacetone acrylamide, 118 parts acrylic acid, 250 parts styrene, 82 parts methyl methacrylate and 10 parts perbutyl D was added for 2 hours. Drop from the dropping funnel, 140 more
The temperature was maintained at 4 ° C for 4 hours to obtain an oil-modified acrylic resin. Subsequently, 150 parts of Epicoat 1004 and 150 parts of Epicoat 828 were used as a second stage reaction raw material in this reaction mixture.
And 2 parts of triethylamine were charged, the mixture was kept at 140 ° C. for 2 hours, then cooled to 80 ° C., and triethylamine 50 was added.
Parts and 1188 parts of deionized water are added to prepare an aqueous dispersion A-
5 was obtained (nonvolatile content 40.0%, viscosity 1000 mPa.
S). Table 1 shows a synthesis example of the above aqueous resin composition.

[0035]

[Table 1]

Comparative Example 1 Acrylic acid 50 was added to the reaction product a-1 obtained in Example 1.
Parts, styrene 150 parts, methyl methacrylate 50 parts,
Butyl methacrylate 50 parts and 6 parts perbutyl D
An aqueous dispersion B-1 was obtained in the same manner as in Example 1 except that the mixture consisting of was reacted (nonvolatile content: 40.0%, viscosity: 1).
000 mPa · S).

Comparative Example 2 A flask similar to that of Example 1 was charged with 250 parts of dehydrated castor oil fatty acid and 250 parts of butyl cellosolve as a solvent as a reaction raw material for the first stage, and while blowing nitrogen gas,
The temperature was raised to 0 ° C., a mixture of 150 parts of styrene, 50 parts of methyl methacrylate, 50 parts of butyl methacrylate, 50 parts of acrylic acid and 6 parts of perbutyl D was dropped from a dropping funnel over 2 hours, and further at 140 ° C. for 4 hours. Holding, an oil-modified acrylic resin was obtained. Subsequently, 350 parts of Epicoat 1004, 100 parts of Epicoat 828 and 2 parts of triethylamine were charged as the second stage reaction raw material into the reaction mixture, and the mixture was kept at 140 ° C. for 2 hours and then cooled to 80 ° C. to obtain triethylamine. 50 parts and 1192 parts of deionized water were added to obtain an aqueous dispersion B-2 (nonvolatile content: 40.0%, viscosity: 1000 mPa · s).
S).

Comparative Example 3 300 parts of dehydrated castor oil were placed in the same flask as in Example 1.
250 parts of butyl cellosolve was charged, the temperature was raised to 140 ° C. while blowing nitrogen gas, and a mixture of 50 parts of acrylic acid, 450 parts of styrene, 100 parts of methyl methacrylate, 100 parts of butyl methacrylate and 14 parts of perbutyl D was added dropwise over 2 hours. After dropping from the funnel and holding at 140 ° C. for 4 hours, the mixture was cooled to 80 ° C., 50 parts of triethylamine and 118 of deionized water were added.
6 parts were added to obtain an aqueous dispersion B-3 (nonvolatile matter 40.
0%, viscosity 1000 mPa · S).

Comparative Example 4 250 parts of butyl cellosolve was charged as a first stage reaction raw material into the same flask as in Example 1, heated to 140 ° C. while blowing nitrogen gas, and acrylic acid 118 was added.
Parts, styrene 300 parts, methyl methacrylate 132
Part, butyl acrylate 150 parts, and a mixture of 14 parts of perbutyl D were dropped from the dropping funnel over 2 hours, and the mixture was kept at 140 ° C. for 4 hours to obtain an acrylic resin. To this reaction product, 150 parts of Epicoat 1004 and 15 parts of Epicoat 828 were used as the second stage reaction materials.
Charge 0 parts and 2 parts of triethylamine, and add 2 parts at 140 ° C.
After holding for a period of time, the mixture was cooled to 80 ° C., and further 50 parts of triethylamine and 1184 parts of deionized water were added to obtain an aqueous dispersion B-4 (nonvolatile matter 40.0%, viscosity 1000).
mPa · S).

Comparative Example 5 300 parts of dehydrated castor oil was placed in the same flask as in Example 1,
250 parts of butyl cellosolve was charged, and the temperature was raised to 140 ° C. while blowing nitrogen gas, 50 parts of acrylic acid, 50 parts of diacetone acrylamide, 400 parts of styrene, 100 parts of methyl methacrylate, 10 parts of butyl methacrylate.
A mixture of 0 parts and 14 parts of perbutyl D was added dropwise from a dropping funnel over 2 hours, and the mixture was kept at 140 ° C. for 4 hours, cooled to 80 ° C., added with 50 parts of triethylamine and 1186 parts of deionized water, An aqueous dispersion B-5 was obtained (nonvolatile matter: 40.0%, viscosity: 1000 m)
Pa · S).

Comparative Example 6 A flask similar to that used in Example 1 was charged with 250 parts of butyl cellosolve as the first stage reaction raw material, and the temperature was raised to 140 ° C. while blowing nitrogen gas, and acrylic acid 118 was added.
Parts, diacetone acrylamide 50 parts, styrene 300
Part, 100 parts of methyl methacrylate, 132 parts of butyl acrylate and 14 parts of perbutyl D were added dropwise from the dropping funnel over a period of 2 hours.
It was kept at 0 ° C. for 4 hours to obtain an acrylic resin. To this reaction product, 1 part of Epicoat 1004 was used as a second stage reaction raw material.
50 parts, 150 parts of Epicoat 828 and 2 parts of triethylamine were charged, and the mixture was kept at 140 ° C. for 2 hours, then, 80
The mixture was cooled to 0 ° C., and 50 parts of triethylamine and 1184 parts of deionized water were added to obtain an aqueous dispersion B-6 (nonvolatile matter 40.0%, viscosity 1000 mPa · S).

Comparative Example 7 A flask similar to that used in Example 1 was charged with 200 parts of butyl cellosolve, heated to 140 ° C. while blowing nitrogen gas, and 50 parts of diacetone acrylamide and 90 parts of acrylic acid were added.
Parts, styrene 250 parts, methyl methacrylate 250
Part, 360 parts of butyl acrylate and 50 parts of perbutyl D were added dropwise from the dropping funnel over 4 hours, and the mixture was kept at 140 ° C. for 4 hours, and then 80 ° C.
The mixture was cooled to 70 ° C., and 70 parts of triethylamine and 1180 parts of deionized water were added to obtain an aqueous dispersion B-7 (nonvolatile matter 40.0%, viscosity 1000 mPa · S). Table 2 shows a synthesis example of the above aqueous resin composition for comparison.

[0043]

[Table 2]

Example 6 Acrylic modified epoxy ester A-obtained in Example 1
1 was used to obtain a water-based anticorrosive paint. A sand mill was used to disperse the pigment according to the following paint formulation. A-1 66.5 parts Triethylamine 0.6 part BYK301 [Leveling agent manufactured by Big Chemie Co., Ltd.] 0.2 part Nopco 8034 [Antifoam agent manufactured by San Nopco Co.] 0.2 part MA-100 [Mitsubishi Chemical Carbon black manufactured by Co., Ltd. 4.0 parts Zinc Hua No. 1 [zinc oxide manufactured by Sakai Chemicals Co., Ltd.] 6.0 parts Super 4S [calcium carbonate by Maruo Calcium Co., Ltd.] 30.0 parts Sand mill A-1 83.5 parts Dicknate 3111 [Dainippon Ink and Chemicals Co., Ltd. 1.0 part dryer] 7.5 parts of a 10% aqueous solution of adipic dihydrazide was added and stirred, An aqueous corrosion resistant coating C-1 using the aqueous resin composition of the present invention was obtained.

Examples 7 to 10 Using the acrylic modified epoxy esters A-2, A-3, A-4 and A-5 obtained in Examples 2 to 5 in the same manner as in Example 6, the above coating composition was prepared. Water-based corrosion resistant paint C-2, C-
3, C-4 and C-5 were obtained. However, the amount of the 10% aqueous solution of adipic dihydrazide was set as follows. Aqueous corrosion resistant coating 10% aqueous solution of adipic dihydrazide C-2 ………… 15.0 parts C-3 ………… 30.0 parts C-4 ………… 15.0 parts C-5 ………… 15 .0 copy

Comparative Examples 8-14 Similar to Example 6, the water dispersion B obtained in Comparative Examples 1-7.
Aqueous corrosion resistant coatings D-1 to D-7 were obtained by blending the above coating compositions with Nos. -1 to B-7. However, the amount of the 10% aqueous solution of adipic dihydrazide was set as follows. Aqueous corrosion resistant coating 10% aqueous solution of adipic dihydrazide D-1 to D-4 ... 0 part D-5 to D-7 ... 15.0 parts Obtained in Examples 6 to 10 and Comparative Examples 8 to 14 above. Unpainted dull steel plate (manufactured by Nippon Test Panel Co., Ltd.)
Under a condition of 0 ° C. and 65% RH, a dry film thickness of 20 μm was applied by an applicator to prepare a test plate. The following performance evaluation was performed on the obtained test plate, and the results are shown in Table 3.

[Pencil hardness] The test plate after the coating of the paint was applied at 60 ° C.
The pencil hardness after 1 day, 2 days, and 3 days when the test plate was left in an atmosphere of 20 ° C. and 65% RH immediately after heating and drying when it was dried by heating for 20 minutes
It was measured according to K5400.

[Gloss] After the test plate was heated and dried at 60 ° C. for 20 minutes and left for 3 days at 20 ° C. and 65% RH, the gloss at 60 ° incident light was measured by a gloss meter (Nippon Denki). (Manufactured by Color Industry Co., Ltd.).

[Corrosion resistance] After the test plate was heated and dried at 60 ° C. for 20 minutes and left in an atmosphere of 20 ° C. and 65% RH for 3 days, a cross cut reaching a steel plate of a bare metal was put thereinto, and a salt spray test was conducted. I went. After 100, 200 and 300 hours, the surface condition of the coating film was judged according to the following criteria. ◯: No change, good ×: Rust occurred on more than 2 mm on one side of the cloth

[Water resistance] After the test plate was heated and dried at 60 ° C. for 20 minutes, it was left in an atmosphere of 20 ° C. and 65% RH for 3 days, and then immersed in warm water of 40 ° C. for 10 days to form a coating film. The surface condition was judged according to the following criteria. ○: Good with no change △: Slight glossiness and normal ×: Poor blister on the whole surface

[Adhesion] The test plate was heated and dried at 60 ° C. for 20 minutes, and then left in an atmosphere of 20 ° C. and 65% RH for 3 days. A: Good (100 to 96) B: Normal (95 to 81) X: Bad (80 to 0)

[Storage stability of paint] The paint was stored at 50 ° C for 14 days.
The dispersion state after standing for one day was visually judged according to the following criteria. ○… Good △… Normal ×… Poor

[0053]

[Table 3]

[0054]

EFFECTS OF THE INVENTION The aqueous resin composition of the present invention is excellent in storage stability as a one-pack type composition by using an active carbonyl group-containing acrylic modified epoxy ester as a reaction partner of a hydrazine derivative. Since the coating film also shows relatively good hardness from the initial stage of drying,
We were able to achieve both practically important characteristics. In addition to excellent corrosion resistance, water resistance, and adhesion, it is also excellent in properties such as hardness, gloss, and appearance of coating film after complete curing. Therefore, as a coating film-forming aqueous resin composition, including a metal substrate. It is useful as a paint for various objects to be coated.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hironobu Akutagawa 5-8 Nishimitabicho Suita City, Osaka Prefecture Nippon Shokubai Co., Ltd.

Claims (5)

[Claims] 1. (A) At least the following essential raw materials (1) to
(3) (1) Bisphenol type epoxy resin, (2) Unsaturated fatty acid, (3) Active carbonyl group-containing (meth) acrylic monomer and carboxyl group-containing (meth) acrylic monomer derived from keto group or aldehyde group An aqueous resin composition characterized in that an active carbonyl group-containing acryl-modified epoxy ester obtained by reacting essential monomer components in any order is dispersed in water. 2. The aqueous resin composition according to claim 1,
The aqueous resin composition according to claim 1, wherein the hydrazine derivative having at least two hydrazino groups in the molecule (B) is dissolved or dispersed. 3. The (A) active carbonyl group-containing acrylic modified epoxy ester is reacted with (1) bisphenol type epoxy resin and (2) unsaturated fatty acid, and then (1).
In the presence of the reaction product of (2) and (2), the active carbonyl group-containing (meth) acrylic monomer and carboxyl group-containing (meth) acrylic monomer derived from the keto group or aldehyde group of (3) are essentially contained. The aqueous resin composition according to claim 1 or 2, which is obtained by polymerizing a monomer component. 4. The (A) active carbonyl group-containing acryl-modified epoxy ester comprises (2) an unsaturated fatty acid and (3) an active carbonyl group-containing (meth) acrylic monomer derived from the keto group or aldehyde group and a carboxyl group. The aqueous resin composition according to claim 1 or 2, which is obtained by polymerizing a monomer component that essentially contains a (meth) acrylic-based monomer, and then reacting the bisphenol-type epoxy resin of (1). . 5. The aqueous resin composition according to claim 1, which is used as a one-pack paint.