JPH02276877A - Aqueous coating composition - Google Patents

Abstract

PURPOSE:To obtain the title composition suitable for electrodeposition coating, because of its reduced heating loss and reduced strain by using a specific compound and a specific basic resin. CONSTITUTION:The subject composition is composed of (A) a compound having at least 2 carbonyl ring urea groups of the formula [n is 0 to 5; X is O. S,-NR1 (R1 is H, 1 to 5C alkyl, hydroxyalkyl, alkylene) in each molecule and (B) a basic resin having an isocyanate group and curable functional group, capable of being soluble or dispersible in water.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an aqueous coating composition, particularly an aqueous coating composition suitable for electrodeposition coating.

(Prior art and its problems) Blocked polyisocyanate was developed as a curing agent for electrodeposition paints, especially cationic electrodeposition paints (Japanese Patent Publication No. 55-34
No. 238), cationic electrodeposition technology has made great progress.

Blocked polyisocyanate is a compound in which highly reactive isocyanate groups are blocked with a low molecular weight blocking agent (usually a low molecular weight alcohol). This compound is unblocked at elevated temperatures to produce isocyanate groups, which trigger a crosslinking reaction.

Problems when using this blocked polyisocyanate include heat loss and distortion due to volatilization of the low molecular weight blocking agent that occurs when the blocks are removed.

On the other hand, Japanese Patent Publication No. 63-24007 discloses the use of a cyclic urea derivative which dissociates upon heating to release a diisoocyanate compound as a curing agent for a curable composition. However, this mechanism also basically involves the dissociation of a low molecular weight substance, which is an organic residue having no reactivity, and has the same problem as the above-mentioned blocked isocyanate.

(Means for Solving the Problems) The present inventors investigated a new curing system that does not substantially involve dissociation or volatilization of low molecular weight substances, and as a result, discovered a system that almost achieved the objective as a water-based paint composition. .

That is, the present invention provides formula (a): [where n is an integer of O to 5, X may be the same or different, and represents an oxygen atom, a sulfur atom, or -NRI (R
I represents hydrogen or an alkyl group having from I to 5 carbon atoms, a hydroxyalkyl group, or an alkylene group. ] A compound having at least two carbonyl cyclic urea groups in one molecule, and (b) a basic resin that can be dissolved or dispersed in water by acid neutralization and has a functional group capable of crosslinking with an isocyanate group. Provided is an aqueous coating composition containing:

The present invention also provides (c) at least two formulas: [wherein n and X are synonyms as defined above. Provided is an aqueous coating composition containing at least two carbonyl cyclic urea groups represented by:

The compound (a) of the present invention contains at least 2 compounds in one molecule.
It has 2, preferably 3 to 50 carbonyl cyclic urea groups represented by formula (1). This compound is basically represented by the following formula [where n is an integer of 0 to 5, m is 2 or more, preferably 3
an integer of ~50, X may be the same or different, an oxygen atom, a sulfur atom, or -NR.

(R1 represents hydrogen or an alkyl group having 1 to 5 carbon atoms, a hydroxyalkyl group, or an alkylene group). ] The above formula (2
The carbonyl cyclic urea group (+) in ) may be of different types.

In formula (2), R has a molecular weight of too, ooo or less, preferably 42 to 20. ．． 000 organic residues. More specifically, R is an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group, an aryl group, or an aralkyl group; , an aryl group, an aralkyl group, an alkaryl group having a molecular weight of 15 to 600, and a glycidyl group, a hydroxyl group, a nitro group, a halogen, a cyano group, a formyl group, and a group substituted with an amino group. . R may also be a polymeric compound residue having a molecular weight of over 600, such as polyester, polyether, polybutadiene, acrylic, polyepoxy resin, etc. In the case of a polymer compound residue, a one-component system (second aspect of the present invention) is possible depending on the types of other groups present as described below.

The compound of component (a) has the formula: [wherein Z is a halogen, an alkoxy group or an aryloxy group having 1 to 10 carbon atoms, and n is a synonym as defined above. ] A compound represented by the formula:RyunX-H)□ (4) In the formula 1,
m, R and X are synonyms as above. It is obtained by reacting a compound represented by J to substitute Z and R-X. Compound (3) can be produced using the following formula. : In this formula, the starting material on the left is a cyclic urea, and the starting material on the right is phosgene itself or phosgene reacted with a suitable alcohol.

Moreover, a polymerizable cyclic urea derivative obtained by replacing the above compound (4) with a compound having both a polymerizable group and -X-H (e, g, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate) It may be obtained by polymerizing with other copolymerizable monomers.

Component (b) of the present invention is a resin having a group capable of crosslinking with an isocyanate and an ionic group capable of being dissolved or dispersed in water by neutralization. Groups capable of crosslinking with isocyanates include groups containing active hydrogen (e, g, primary to secondary amino groups, hydroxyl groups, thiol groups, carboxyl groups, etc.). The groups are specifically various ionic groups, specifically cationic Ji&(e, g, primary to tertiary amino groups, quaternary ammonium groups, tertiary thionium groups, phosphonium groups).
or anionic groups (e, g, carboxylic acid group, sulfonic acid group, phosponic acid group). The content of ionic groups is 30 to 300 mmol/1009 (solid content). If it is less than 30 mmol/100 g (solid content), water solubility or dispersibility will be insufficient. 300 mmol
If it exceeds /+00ip (solid content), film functions such as corrosion resistance will deteriorate. The compound that neutralizes the ionic group is an ionic group or a cationic compound, an organic acid such as formic acid, acetic acid, lactic acid, sulfonic acid, or phosphonic acid, or a mineral acid such as sulfuric acid or hydrochloric acid, or an anionic compound containing Examples include tertiary amines, basic bases such as ammonia, and inorganic bases such as sodium hydroxide. The basic skeleton of this component (b) can be various polymer skeletons, and for example, epoxy systems, polybutadiene systems, polybutene systems, acrylic systems, polyurethane systems, polyester systems, polyamide systems, etc. are common. Methods for introducing the respective groups into these polymer backbones are known and will not be described in detail here.

In another aspect of the present invention, the above components (a) and (
A resin having both groups of b) (component (C)) may be used. Specifically, a cyclic urea group represented by formula (1) is introduced into the resin of component (b). The cyclic urea group can be introduced by substituting the -X-H group in the polymer skeleton using the aforementioned compound (3), or by replacing the -X-H group with the polymerizable group.
This can be easily carried out by a method such as copolymerization of a compound having both H. In this case, the ionic group is the component (a
) and (b).

The present invention provides the above components (a) and (b), or component (c).
) containing water (preferably deionized water) as a medium, especially electrocoating compositions, but if necessary a small amount of an organic solvent (e.g. ethylene glycol monobutyl ether, ethylene glycol Monobutyl ether, ethylene glycol monobutyl ether, methanol, ethanol, isopropyl alcohol, n-
Butyl alcohol, 5ec-butyl alcohol, t-butyl alcohol, dimethylformamide, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone,
(isophorone, oxane, toluene, xylene, ethyl acetate, propyl acetate, butyl acetate, amyl acetate, etc.) may also be used. In the case of two components (a) and (b),
Component (a) accounts for a total of 10.5 to 70% by weight, preferably 5 to 50% by weight.

In addition, conventionally used additives such as pigments, surfactants, curing accelerators, antifoaming agents, and curing catalysts can be used in the aqueous coating composition of the present invention, if necessary. The total amount of additives is usually 10 to 50% by weight based on the total solids content.

Examples of pigments include color pigments such as carbon black, titanium oxide, iron oxide, cyanine blue, and Shinkanya red, extender pigments such as calcium carbonate, aluminum silicate, and barium sulfate, strontium chromate, and basic lead silicate. Examples include, but are not limited to, rust-preventing pigments.

Curing catalysts that can be used include polyisocyanates as well as 6-metal salts (e, g, tin or lead-based), active metal esters (e, g, tin-based), and tertiary amines (e, g, tin-based).

triethylamine, dimethylbenzylamine, azobicycloundecene), etc. are used. However, the composition of the present invention can be cured without a catalyst, and in particular, in cationic jl 6
Hardening progresses.

The aqueous coating composition of the present invention can be applied by dipping, running water or spraying, but electrodeposition is more suitable.

When applying the composition of the present invention by electrodeposition, a conventionally known method is used, usually at a bath temperature of 15 to 35°C and a solid content concentration of 3 to 2.
5% by weight and a coating voltage in the range of 30 to 350 cm. In this case, examples of the object to be coated include metals such as iron, copper, aluminum, and zinc, alloys thereof, and conductive organic substances. Curing is usually carried out at a temperature of 120 to 220°C for 10 to 40 minutes.

(Effects of the Invention) According to the present invention, the disadvantages caused by using blocked polyisocyanate are eliminated, and the loss on heating is small and distortion is reduced. In addition, in the present invention, by introducing a bond with higher polarity into the part that connects the original urea,
Formation of aqueous compositions has become easier. Without being limited to any particular theory, it is believed that in the composition of the present invention, group (1) is ring-opened by heating to form an isone anate group as shown in the formula.

This isone anate group contributes to the curing reaction.

(Example) The present invention will be explained in more detail with reference to Examples. The invention is not limited to these examples.

Production example ■ Aminated polybutadiene Nisseki polybutadiene B-2000 (number average molecular weight 2.0
00.1.2 bond 65%) is epoxidized using peracetic acid to produce epoxidized polybutadiene with 6.4% oxirane oxygen content! ! ! Built.

After charging 00 g of this epoxidized polybutadiene I O and 354 g of ethyl cellosolve into a 2 g autoclave, 62.1 g of dimethylamine was added and the reaction was allowed to proceed at 150° C. for 5 hours. Unreacted amine was distilled off to produce an aminated polybutadiene resin solution. The amine value of this product is 1
It was 20 mmol/100 g (solid content). Non-volatile content 75% Production Example 2 Put EPONloo with an epoxy equivalent of 485 into a suitable reaction vessel.
I 9709 and polycaprolactone diol (trade name: PCPO200 Union Carbide Coboration) 2659. This was heated at 100°C under a nitrogen atmosphere.
and add 0.46 g of dimethylbenzylamine. The reaction mixture is further heated to 130° C. and maintained at this temperature for 1.5 hours. The batch is cooled to 110° C. and 110 g of methyl isobutyl ketone are added, followed by 39.8 g of methyl isobutyl ketone of diethylenetriamine and then 1009 g of methyl isobutyl ketone. Batch temperature is 7
Cooling was continued until the temperature reached 0°C, and after adding 53.19 g of diethylamine at this temperature, the reaction temperature was raised to 120°C, maintained for 3 hours, and then taken out.

Production Example 3 Aminated Epoxy B Place EPONloo with an epoxy equivalent of 485 in a suitable reaction vessel.
I 9709 and polycaprolactone diol (trade name: PCPO200 Union Carbide Coboration) 2659. This is heated to 100° C. under nitrogen atmosphere and 0.46 g of dimethylbenzylamine is added.

The reaction mixture is further heated to 130° C. and maintained at this temperature for 1.5 hours. The batch is cooled to 110° C. and methyl isobutyl ketone 1109 is added, followed by jetanolamine 21.09 and then methyl isobutyl ketone 1009. Cooling is continued until the batch temperature reaches 70°C, and after adding 53.19 g of diethylamine at this temperature, the reaction temperature is raised to 120°C, maintained for 3 hours, and then taken out.

Production Example 4 The following compound obtained by reacting the epoxy ester compound bisphenol A and epichlorohydrin in the presence of an alkali catalyst is a bisphenol type epoxy resin (
Product name Epicoat 1004; Digestion Shell Epoxy Co., Ltd.
Dissolve 1000g of ethyl cellosolve in 343g of ethyl cellosolve,
Acrylic acid 76°3g, hydroquinone 10g and N
, 5g of N-dimethylaminoethanol was added, and 100
℃ for 5 hours, component (b) of the present invention -
A resin solution as a component was synthesized.

The acid value of this product was 2 mmol/100 g/1 solid content concentration was 75% by weight.

Production Example 5 Polyfunctionalized carbonylpropylene urea compound A phenoxycarbonylpropylene urea 100 g (450 mmo
l) and 59 g (4
50 mmol) in 900 ml of dioxane at 85-90°C
It was heated and dissolved. There dibutyltin dilaurate 40
0 mg was added, and heating and stirring were continued for 13 hours. After the reaction was completed, the solution was condensed, and the resulting crude product was reprecipitated with ether to obtain 2-methacryloyloxyethyloxycarbonylpropylene urea (909%) in a yield of 77.5%.

50 g of this 2-methacryloyloxyethyloxycarbonylpropylene urea, 150 g of 2-ethylhexyl acrylate and dioxane 4009 were mixed at 80 to 85°C.
The mixture was heated and dissolved. There azobisisobutyronitrile 4
．． 89 was dissolved in 200 g of dioxane and added dropwise over 1.5 hours. Then, by aging for 2 hours, the molecule IMn=
2670 objects were obtained.

Production Example 6 Polyfunctionalized carbonylpropylene urea compound B Production Example 5
80 to 85 g of 2-methacryloyloxyethyloxycarbonylpropylene urea 1509 and 2-ethylhexyl acrylate 509 obtained in
The mixture was heated and dissolved at ℃.

Thereto, 4.89 g of azobisisobutyronitrile dissolved in dioxane 2009 was added dropwise over 1.5 hours.

After that, by aging for 2 hours, the molecule ff1Mn=98
20 objects were obtained.

Production Example 7 100g of 2-methacryloyloxyethyloxycarbonylpropyleneurea obtained in Production Example 5, 50y of N,N-dimethylaminopropylmethacrylamide, 50g of 2-hydroxyethyl methacrylate, and dioxane 4009 were heated and dissolved at 80 to 85°C. . Thereto, 4.89 g of azobisisobutyronitrile dissolved in dioxane 2002 was added dropwise over 1.5 hours. Thereafter, by aging for 6 hours, the target product with a molecular weight Mn=4600 was obtained.

Production Example 8 Polyfunctionalized carbonylpropylene urea compound Production Example 5
2-methacryloyloxyethyloxycarbonylpropylene urea 2009 obtained in
The mixture was heated and dissolved at 0 to 85°C. 1. Dissolve 4.89 of azobisisobutyronitrile in dioxane 2009.
It was added dropwise over 5 hours. Thereafter, by aging for 6 hours, the target product with a molecular weight Mn=2400 was obtained.

Production Example 9 Polyfunctionalized carbonylpropylene urea compound E1.6-
Hexanediol 1079 and 400 g of phenoxycarbonylpropylene urea were dissolved in dioxane 3Q and dibutyltin dilaurate I09 was added thereto. Thereafter, the mixture was stirred at 85° C. for 8 hours. After the reaction is complete, concentrate, wash,
After purification, 304 g of the target product, 1,6-hexamethylene di(oxycarbonylpropylene urea), was obtained.

(Yield 83%) Physical property values are as follows.

Melting point near 4-77℃ NMR: 6.71 (bs), 4.21 (t), 3.75
(m) 3.32 (dt), 1.88-1.47 (m) Production example! 0 Polyfunctionalized carbonylpropylene urea compound F 340 g of bisphenol A diglycidyl ether (molecular weight 340, epoxy equivalent 170) is dissolved in dioxane 9509, heated, and then gradually added dropwise with jetanolamine 21O9. After stirring for 2 hours, phenoxycarbonylpropylene urea 7709 dissolved in 0 g in dioxane 3Q was charged, 13.29 dibutyltin dilaurate was added, and the mixture was heated to 80°C for 12 hours.
time, add 269 dibutyltin dilaurate, 95
Stirring was continued for 30 hours at °C. After the reaction is complete, concentrate, wash,
After purification, the desired product was obtained in 6259 (yield 70%).

Production Example 11 Polyfunctionalized Carbonylpropylene Urea Compound G Phenoxycarbonylpropylene urea 899 and 24 g of hexamethylene diamine were heated and dissolved in 200 g of dioxane. After 1 hour, the completion of the reaction was confirmed by thin layer chromatography, and as a result of concentration and washing, the target product was found at 70.59% (yield 94%).
I got it. The physical property values are as follows.

Melting point: 196-198°C NMR: 9.23, 3.26 (m), 5.42, 1.9
2(tt), 3.83(t), I, 54(+
e) 3.33 (dt), 1.35 (m) 100 g of 3-amino-1-propatol and 586 g of phenoxycarbonylpropylene urea were added to dioxane 512;
Furthermore, 1 g of dibutyltin dilaurate was added and the mixture was heated to 80°C.
Heat and stir for 5 hours. The reaction crude product was condensed and washed to obtain 217 g (yield: 50%) of the desired product.

Comparative Production Example Preparation of Blocked Isocyanate 2.4-/2,6-Toluene Diisocyanate 80/
2-Ethylhexanol 2189 was added to 291 g of the 20 (weight ratio) mixture under stirring in a dry nitrogen atmosphere, and the reaction temperature, which was cooled from the outside, was maintained at 38 DEG C. to prepare a polyurethane crosslinking agent. This was further kept at 38°C for half an hour, then 6
The temperature was raised to 0°C, and 759 g of trimethylolpropane was added, followed by 80 rag of dibutyltin dilaurate. After the initial exotherm, the batch is held at 121° C. for 1.5 hours until substantially all of the isocyanate residues have been consumed, as determined by infrared analysis. This batch was further diluted with 249 g of ethylene glycol ether and 1500 g of dioxane to obtain the desired isocyanate block.

Example 1 200 parts of aminated polybutadiene of Production Example I, Production Example 4
After mixing 200 parts of the epoxy ester and 400 parts of the polyfunctionalized carbonylpropylene urea compound A of Production Example 5 until uniform, 5 g of acetic acid was added to neutralize the mixture. Next, deionized water was gradually added to prepare an aqueous solution having a solid content concentration of 20% by weight.

This 20% by weight aqueous solution 20009, carbon black 4
9. Basic lead silicate 20g and glass beads 20009
into a 5Q stainless steel beaker and mix with a high-speed rotating mixer.
After stirring vigorously for an hour, the glass peas were filtered. Next, deionized water containing 0.329% of manganese acetate as manganese metal was added so that the solid content concentration was 16.5% by weight to prepare an electrodeposition coating liquid.

Cathode deposition type electrodeposition coating was performed using the above electrodeposition coating liquid, using the carbon electrode as an anode and the zinc phosphate treated plate as a cathode.

The test results are shown in Table-1.

Example 2 0 g of the polyfunctional carbonylpropylene urea compound B4O of Production Example 6 was added to 400 g of the aminated epoxy of Production Example 3 and mixed until uniform, and then 6.6 g of acetic acid was added for neutralization. Next, deionized water was gradually added to prepare an aqueous solution having a solid content concentration of 20% by weight.

This 20% by weight aqueous solution 20009, carbon black 4
9. Basic lead silicate 20g and glass beads 20009
was placed in a 512 stainless steel beaker and stirred vigorously for 2 hours using a high-speed rotating mixer, and then the glass peas were filtered.

Next, deionized water was added so that the solid content concentration was 6.5% by weight to prepare an electrodeposition coating liquid.

Cathode deposition type electrodeposition coating was performed using the above electrodeposition coating liquid, using the carbon electrode as an anode and the zinc phosphate treated plate as a cathode.

The test results are shown in Table-1.

Example 3 200 parts of aminated polybutadiene of Production Example 1, Production Example 4
200 parts of the epoxy ester and 30 parts of the polyfunctionalized carbonylpropylene urea compound E of Production Example 9 were uniformly mixed, and 5 g of acetic acid was added to neutralize the mixture.

Next, deionized water was gradually added to prepare an aqueous solution having a solid content concentration of 20% by weight. Thereafter, an electrodeposition coating liquid was prepared using this aqueous solution in the same manner as in Example 1, and cathodic deposition type electrodeposition coating was performed. The test results are shown in Table-1.

Example 4 Aminated polybutadiene 20 of Production Example 1 was used to prepare an aqueous solution.
0 parts, 200 parts of the epoxy ester of Production Example 4, Production Example 1
0 polyfunctionalized carbonylpropylene urea compound F50
The same operation as in Example 3 was carried out, except that part was used. The test results are shown in Table 1.

Example 5 To prepare an aqueous solution, 400 parts of the aminated epoxy of Production Example 3,
The same operation as in Example 3 was performed except that 150 parts of the polyfunctionalized carbonylpropylene urea compound F of Production Example 10 was used. The test results are shown in Table-1.

Example 6 To prepare an aqueous solution, 400 parts of the aminated epoxy of Production Example 3,
The same operation as in Example 3 was performed except that 0600 parts of the polyfunctionalized carbonylpropylene urea compound of Production Example 7 was used. The test results are shown in Table 1. Example 7 To prepare an aqueous solution, 400 parts of the aminated epoxy of Production Example 3,
The same operation as in Example 3 was performed except that 300 parts of the polyfunctionalized carbonylpropylene urea compound D of Production Example 8 was used. The test results are shown in Table-1.

Example 8 To prepare an aqueous solution, 400 parts of the aminated epoxy of Production Example 2,
The same operation as in Example 3 was performed except that 100 parts of the polyfunctionalized carbonylpropylene urea compound G of Production Example 11 was used. The test results are shown in Table-1.

Example 9 To prepare an aqueous solution, 400 parts of the aminated epoxy of Production Example 3,
The same operation as in Example 3 was performed except that 87 parts of the polyfunctionalized carbonylpropylene urea compound H of Production Example 12 was used. The test results are shown in Table-1.

Example IO The polyfunctionalized carbonylpropylene urea compound C8009 of Production Example 7 was neutralized by adding 5.39 g of acetic acid. Next, deionized water was gradually added to prepare an aqueous solution having a solid content concentration of 20% by weight.

This 20% by weight aqueous solution 20009, carbon black 4
9. Basic lead silicate 202 and glass beads 2000g
into a 5Q stainless steel beaker and mix with a high-speed rotating mixer.
After stirring vigorously for an hour, the glass peas were filtered. Next, deionized water containing 0.329 of manganese acetate as manganese metal was added so that the solid content concentration was 16.5% by weight to prepare an electrodeposition coating liquid.

Cathode deposition type electrodeposition coating was performed using the above electrodeposition coating liquid, using the carbon electrode as an anode and the zinc phosphate treated plate as a cathode.

The test results are shown in Table-1.

Example +1 The polyfunctionalized carbonylpropylene urea compound F800y of Production Example 10 was neutralized by adding 5.39 g of acetic acid. Next, deionized water was gradually added to prepare an aqueous solution having a solid content concentration of 20% by weight.

2000y of this 20% aqueous solution, carbon black 4
g, basic lead silicate 209 and glass beads 20009
Put 5g of the powder into a stainless steel beaker and mix with a high-speed rotating mixer.
After stirring vigorously for an hour, the glass peas were filtered. Next, deionized water was added so that the solid content concentration was 16.5% by weight to prepare an electrodeposition coating liquid.

Cathode deposition type electrodeposition coating was performed using the above electrodeposition coating liquid, using the carbon electrode as an anode and the zinc phosphate treated plate as a cathode.

The test results are shown in Table-1.

Comparative Example 1 200 parts of aminated polybutadiene of Production Example I, Production Example 4
200 parts of the epoxy ester and 138 parts of the blocked isocyanate compound of Comparative Production Example were mixed until uniform, and 59% of acetic acid was added to neutralize the mixture. Next, deionized water was gradually added to prepare an aqueous solution having a solid content concentration of 20% by weight.

This 20% by weight aqueous solution 20009, carbon black 4
9. Basic lead silicate 20g and glass beads 20009
into a 5Q stainless steel beaker and mix with a high-speed rotating mixer.
After stirring vigorously for an hour, the glass peas were filtered. Next, deionized water containing 0.329 of manganese acetate as manganese metal was added to adjust the solid content concentration to 6.5% by weight to prepare an electrodeposition coating liquid.

Cathode deposition type electrodeposition coating was performed using the above electrodeposition coating liquid, using the carbon electrode as an anode and the zinc phosphate treated plate as a cathode.

The test results are shown in Table-1.

Comparative Example 2 400 parts of the aminated epoxy of Production Example 3 for preparing an aqueous solution,
The same operation as in Comparative Example 1 was performed except that 414 parts of the blocked isocyanate of Comparative Production Example was used. Display test results -
Shown in 1.

Comparative Example 3 400 parts of the aminated epoxy of Production Example 2 for preparing an aqueous solution,
The same operation as in Comparative Example I was performed except that 414 parts of the blocked isocyanate of Comparative Production Example was used. Display test results -
Shown in 1.

Example 12 The resin components of Example 2 were mixed and similarly neutralized with acetic acid, and then deionized water was added to prepare an aqueous solution having a solid content concentration of 40% by weight. Table 2 shows the results of dipping and painting a zinc phosphate treated board with this product.

Example 13 The same operation as in Example 12 was performed except that the mixed resin components were the same as in Example 5. The test results are shown in Table 2.

Example 14 Example 12 except that the mixed resin components are the same as in Example 10.
The same operation was performed. The test results are shown in Table 2.

Comparative Example 4 The same operation as in Example 11 was performed except that the mixed resin components were the same as in Comparative Example 2. The test results are shown in Table-2.

1) Forced drying at 50°C under reduced pressure, 30 minutes later 2) Baking conditions at 200°C x 25 m 1n Patent applicant Nippon Paint Co., Ltd. Agent Patent attorney Aohaku Ao (and 2 others) 1) 20
0℃×25m1n baking conditions

Claims (1)

[Claims] 1. Formula (a): ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (1) [In the formula, n is an integer of 0 to 5, X may be the same or different, and represents an oxygen atom, Sulfur atom, or -NR_1-(R
_1 represents hydrogen or an alkyl group having 1 to 5 carbon atoms, a hydroxyalkyl group, or an alkylene group. ] A compound having at least two carbonyl cyclic urea groups in one molecule, and (b) a basic resin that can be dissolved or dispersed in water by acid neutralization and has a functional group capable of crosslinking with an isocyanate group. Aqueous paint composition containing. 2. 3 carbonyl cyclic urea groups of formula (1) in one molecule
50 and a molecular weight within 100,000. 3. The composition according to claim 1, wherein X in formula (1) is an oxygen atom. 4. The composition of claim 1, wherein the aqueous coating composition is electrodeposited at a cathode. 5. (c) At least two formulas: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) [In the formula, n and X are synonyms as above. ] An aqueous coating composition comprising at least two carbonyl cyclic urea groups represented by the following formula and a basic resin which has a functional group capable of crosslinking with an isocyanate group and is soluble or dispersible in water by acid neutralization. 6. The composition according to claim 5, wherein the basic resin has 3 to 50 carbonyl cyclic urea groups of formula (1) and has a molecular weight of within 100,000. 7. The composition according to claim 5, wherein -X- in formula (1) is an oxygen atom. 8. The composition of claim 5, wherein the aqueous coating composition is electrodeposited at the cathode.