JPH11140353A - Electrodepositon coating composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an electrodeposition which can give a coating film having excellent matte effect without roughening the skin of the film and having excellent cissing resistance by formulating a pigment dispersion paste for an electrodeposition coating material, containing silica, a pigment component, and amine-modified epoxy resins and a water-soluble organic solvent with an amine-modified epoxy resin forming an electrodeposition coating film and a curing agent. SOLUTION: The formulation ratio of the tertiary-amine modified epoxy resin to the quaternary-amine-modified epoxy resin is usually 1:1 to 3:1. Silica is mixed with a pigment component, a tertiary-amine-modified epoxy resin and a water-soluble organic solvent to disperse the silica and the pigment composition in the form of particles having a specified particle size. A tertiary-amine-modified epoxy resin is added to the resultant mixture to produce a pigment dispersion paste for an electrodeposition coating material, and this paste is mixed with an amine-modified epoxy resin for forming an electrtodeposition coating film and a curing agent to obtain an electrodeposition coating composition. In addition to the case where the silica is added to the pigment dispersion paste, it may be formulated to a resin emulsion for a main binder, containing an electrodeposition film-forming amine-modified epoxy resin and an organic solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrodeposition coating composition and a method for producing the same. More particularly, the present invention relates to a matte electrodeposition coating composition having a matting effect and having excellent repelling resistance, and a method for producing the same.

[0002]

2. Description of the Related Art A matte electrodeposition coating can be used as a means of improving not only the surface protection of various metal products but also its aesthetic appearance, especially a sense of quality, such as a solid feeling, because a coating film with suppressed metallic luster can be obtained. Its demand is expanding.

There are various methods for obtaining a matte electrodeposition coating film. For example, an inorganic transparent pigment having a matting effect is contained in an electrodeposition coating bath, and together with an organic resin component of the coating at the time of electrodeposition coating. There is a method in which an inorganic transparent pigment is precipitated and irregularly reflected by the inorganic transparent pigment.

However, the coating film obtained by this method is a coating film in which the particles of the inorganic transparent pigment are non-uniformly dispersed, and as a result, the coating film surface becomes rough, the coating film characteristics are reduced, and gloss unevenness occurs. There was a problem.

On the other hand, cationic electrodeposition paints have high rust prevention properties and are therefore widely used industrially, for example, as paints for automobile bodies.

However, since a crater called repelling may be formed on the surface of the cured coating film, development of an electrodeposition paint having excellent repelling resistance has been desired.

[0007]

SUMMARY OF THE INVENTION The present inventors have conducted intensive studies in view of the above points, and as a result, have found that a tertiary amine-modified epoxy resin and When a quaternary amine-modified epoxy resin is used or an amine-modified epoxy resin is used as a resin for the main binder and silica is added thereto, surprisingly, an excellent matting effect can be obtained without roughening the coating film surface, and the The present inventors have found that a matte electrodeposition coating composition having excellent repellency can be obtained, and have completed the present invention.

[0008] It is an object of the present invention to provide a matte electrodeposition coating composition which gives an excellent matting effect without roughening the coating film surface and has excellent repelling resistance, and a method for producing the same.

[0009]

That is, the present invention provides a pigment dispersion paste for electrodeposition paint containing silica, a pigment component, a tertiary amine-modified epoxy resin and a quaternary amine-modified epoxy resin, and a water-soluble organic solvent. An electrodeposition coating composition comprising an electrodeposition film-forming amine-modified epoxy resin and a curing agent.

The present invention also provides the electrodeposition coating composition as described above, wherein the tertiary amine-modified epoxy resin and the quaternary amine-modified epoxy resin have a compounding ratio of 1: 1 to 3: 1. Is provided.

Further, the present invention provides a pigment dispersion paste for electrodeposition paint containing a pigment component, an amine-modified epoxy resin and a water-soluble organic solvent, silica, an electrodeposited film-forming amine-modified epoxy resin and a water-soluble organic solvent. The present invention provides an electrodeposition coating composition containing a resin paste for a main binder containing: and a curing agent.

Further, the present invention provides a method for mixing a silica, a pigment component, a tertiary amine-modified epoxy resin, and a water-soluble organic solvent to disperse silica and a pigment component to a predetermined particle size, and then forming a quaternary amine-modified epoxy resin. The method for producing the electrodeposition coating composition according to the above, further comprising mixing to produce a pigment dispersion paste for an electrodeposition coating composition, and mixing an electrodeposition film-forming amine-modified epoxy resin with a curing agent. Is provided.

Further, the present invention relates to a method of mixing silica, an amine-modified epoxy resin, and a water-soluble organic solvent, dispersing the silica to a predetermined particle size, further mixing the amine-modified epoxy resin, and then adding neutralized acid to water. Is added thereto to produce a resin paste for a main binder containing silica, and a pigment dispersion paste for an electrodeposition paint containing a pigment component, an amine-modified epoxy resin and a water-soluble organic solvent, and cured. And a method for producing the electrodeposition coating composition as described above, which comprises mixing an electrodeposition coating composition.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The gist of the present invention is a combination of silica and an amine-modified epoxy resin, and there are a case where silica is blended into a pigment dispersion paste and a case where it is blended into a resin emulsion for a main binder.
When silica is blended in the pigment dispersion paste, an amine-modified epoxy resin is used as the electrodeposition film-forming resin, which is a resin for the main binder, and the pigment-dispersion resin is particularly a tertiary amine-modified epoxy resin among amine-modified epoxy resins. A quaternary amine-modified epoxy resin must be used. on the other hand,
When a resin paste for a main binder obtained by mixing silica in a resin emulsion for a main binder is used in the present invention, the electrodeposition film-forming resin and the pigment-dispersing resin may be amine-modified epoxy resins.

Next, the components of the present invention will be described with reference to specific examples. The silica used in the present invention is silicon dioxide, and a commercially available product can be used. Powdered silica having an average particle size of 0.5 to 15 μm is used.
It is preferred to use silica having an average particle size of 8.0μ. The amount of the pigment dispersion paste is 5 to 50% by weight, preferably 10 to 25% by weight, based on the solid content of the resin in the electrodeposition coating composition obtained by combining the pigment dispersion resin and the electrodeposition film forming resin. Alternatively, it is blended with the resin emulsion for the main binder. If the amount is less than 5% by weight, the matting and repelling effects are reduced, and if it is more than 50% by weight, the matting effect is increased, but the coating film surface is roughened.

When the above silica is blended into the pigment dispersion paste, it may be blended together with the pigment component. The pigment component used in the pigment-dispersed paste includes a coloring pigment, an extender pigment, a rust-preventive pigment, and the like, but the pigment component used herein is defined as containing no silica. The coloring pigment is a component for imparting a predetermined color to the electrodeposition coating film, and examples thereof include carbon black, titanium white, lead white, and red iron oxide. The extender pigment is a component for imparting necessary properties to the electrodeposition paint, for example, kaolin, antimony oxide, zinc oxide, basic lead carbonate, basic lead sulfate, barium carbonate, calcium carbonate, aluminum Examples thereof include silica, magnesium carbonate, magnesium silica, and talc. Further, the rust preventive pigment is a component for improving the rust preventive property of the electrodeposition coating film, and is added to the pigment component used in the present invention as needed. In addition, as a rust preventive pigment, for example, strontium chromate, lead chromate, lead red, basic lead silicate, lead phosphate, lead tripolyphosphate, cyanamide lead, lead oxide, zinc phosphomolybdate,
Aluminum phosphomolybdate and the like can be mentioned.

The compounding amount of the pigment component is 0.05: 1 to 5 by weight with respect to the amine-modified epoxy resin for dispersing the pigment.
It is preferable to set 0: 1, and 0.1: 1 to 20: 1.
Is more preferably set to. The pigment component ratio is 0.0
If it is less than 5, the viscosity due to the resin component increases significantly,
Dispersion becomes difficult. Further, in order to form a normal electrodeposition film, a large amount of pigment-dispersed paste must be used, which may cause a problem such as a decrease in rust prevention of the electrodeposition film. On the other hand, when the pigment component exceeds 50, the dispersion efficiency is significantly reduced, and the dispersion becomes difficult. Alternatively, even if it can be dispersed to avoid it, aggregation of the electrodeposition paint,
Precipitation occurs, causing practical problems.

In the present invention, the resin used for the pigment-dispersed resin and the electrodeposited film-forming resin as the main binder is an amine-modified epoxy resin. For example, epoxy resin into which a quaternary ammonium group is introduced or epoxy resin into which a tertiary amino group is introduced is used. However, when silica is blended in the pigment-dispersed paste, it is necessary to use both a tertiary amine-modified epoxy resin and a quaternary amine-modified epoxy resin as the pigment-dispersed resin.

The epoxy resin used for preparing such an amine-modified epoxy resin includes a so-called polyepoxide resin having an average of one or more 1,2-epoxy groups in one molecule. The epoxy equivalent of such an epoxy resin is preferably from 150 to 2,000,
00-1500 are more preferable. Epoxy equivalent is 15
If it is less than 0, film formation is difficult during electrodeposition, and an electrodeposition coating film may not be obtained. Conversely, if it exceeds 2,000, the amount of cationic groups per molecule is insufficient,
In some cases, sufficient water solubility cannot be obtained.

The number average molecular weight of such an epoxy resin is preferably from 300 to 10,000, and more preferably from 800 to
5,000 is more preferred. Number average molecular weight of 10,000
If it exceeds 0, the viscosity may be too high and poor dispersion may occur. Conversely, if it is less than 300, the corrosion resistance of the electrodeposition coating film may be reduced.

Specific examples of the above-mentioned epoxy resin include polyglycidyl ether of polyphenol and 1,2-
An acrylic polymer having an epoxy group as a pendant group is exemplified. Here, the polyglycidyl ether of polyphenol is generally obtained by reacting polyphenol with epichlorohydrin or dichlorohydrin in the presence of an alkali. Specific examples of polyphenols include bis (4-hydroxyphenyl) -2,2-
And propane, 4,4-dihydroxybenzophenone, bis (4-hydroxyphenyl) -1,1-ethane and the like. On the other hand, an acrylic polymer having a 1,2-epoxy group as a pendant group is generally obtained by copolymerizing an acrylic monomer having a 1,2-epoxy group, such as glycidyl methacrylate, alone or with another acrylic monomer. be able to.

An amine-modified epoxy resin is obtained by introducing a quaternary ammonium group or a primary to tertiary amino group into the epoxy resin. As the amine-modified cationizing agent in this case, an acid salt of a primary amine, a secondary amine, or a tertiary amine is used. Specifically, butylamine,
Octylamine, diethylamine, dibutylamine, methylbutylamine, monoethanolamine, diethanolamine, N-methylethanolamine, triethylamine, N, N-dimethylethanolamine, and secondary amine obtained by blocking amino primary amine are used. Can be In addition, two or more of these amines may be used in combination.

When introducing a quaternary ammonium group or a primary to tertiary amino group into an epoxy resin by using such an amine, the amine is reacted with the epoxy resin by using an approximately equivalent amount of the epoxy group of the epoxy resin. . After this reaction, the product is neutralized using an acid. As the acid, formic acid, lactic acid, acetic acid, propionic acid, butyric acid, dimethylolpropionic acid, N-acetylglycine, N-acetyl-β
-Alanine and the like are used.

The amine equivalent of the epoxy resin into which the quaternary ammonium group or the like has been introduced in this manner is 0.3 to 4.0.
0 meq / g is preferred. The amine equivalent is 0.3 meq /
If the amount is less than g, emulsification and water-solubility become difficult, and
If it exceeds 0 meq / g, the water resistance of the electrodeposition coating film may be insufficient.

The amine-modified epoxy resin as described above may be further modified by reacting it with a half-blocked isocyanate. A half-blocked isocyanate for obtaining such a modified epoxy resin is obtained by reacting a polyisocyanate with an active hydrogen-containing compound. This reaction is preferably carried out by cooling to 40 to 50 ° C. while stirring and dropping the active hydrogen-containing compound in the presence of a tin catalyst, if necessary. In the reaction between the polyisocyanate and the active hydrogen-containing compound, the isocyanate residue in one molecule of the generated half-blocked isocyanate is 1.0 to 1.0.
It is preferable to set the reaction ratio of the active hydrogen-containing compound by stoichiometric calculation so as to be 0.5 molar equivalent, preferably 0.99 to 0.88 molar equivalent. If the isocyanate residue in one molecule of the half-blocked isocyanate exceeds 1.0 molar equivalent, gelation may occur during the reaction with the epoxy resin. Conversely, if it is less than 0.5 molar equivalent, the total amount of the blocked isocyanate remaining without reacting with the epoxy resin increases, which may hinder water solubility.

The polyisocyanate used for producing such a half-blocked isocyanate includes 1
There is no particular limitation as long as the molecule has an average of two or more isocyanate groups. Specifically, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, Aliphatic diisocyanates such as lysine diisocyanate and butylidene diisocyanate, 1,3
-Cyclopentane diisocyanate, 1,4-cyclodiisocyanate, hexane diisocyanate, 1,2-
Alicyclic diisocyanates such as cyclohexane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, aromatic diisocyanates such as 1,4-naphthalene diisocyanate, 1,5-naphthalene diisocyanate and 1,4-dinaphthalene diisocyanate, 4, Aliphatic-aromatic diisocyanates such as 4'-diphenylenemethane diisocyanate, 2,4- or 2,6-tolylene diisocyanate or mixtures thereof, 4,4'-toluidine diisocyanate and 1,4-xylylene diisocyanate compounds; Nuclear-substituted diisocyanates such as dianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate and chlorodiphenylene diisocyanate;
Triphenylmethane-4,4 ', 4 "-triisocyanate, triisocyanate such as 1,3,5-triisocyanate toluene, 4,4'-diphenyldimethylmethane-2,2', 5,5'- Examples include tetraisocyanates such as tetraisocyanate, and polymerized polyisocyanates such as tolylene diisocyanate dimer and trimer.

The above-mentioned polyisocyanate preferably has an isocyanate group having different reactivity in one molecule, which is advantageous for a partial blocking reaction.

On the other hand, active hydrogen-containing compounds used for producing a half-blocked isocyanate include:
For example, alcohols having 1 to 20 carbon atoms, amines, carboxylic acids, oximes, caprolactams and the like can be mentioned. Among them, alcohols include methanol, ethanol, propanol, butanol, amyl alcohol, hexyl alcohol, 2-ethylhexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, 3,3,5-trimethylhexanol, decyl alcohol, lauryl alcohol, Aliphatic alcohols such as stearyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monomethyl ether, benzyl alcohol, and cyclohexanol , Phenol, cresol, xylenol, black Phenols, phenols such as ethyl phenol.

Examples of the amine include xylidine, aniline, butylamine, dibutylamine and the like. As carboxylic acids, formic acid, acetic acid, propionic acid,
Octyl acid, stearic acid and the like can be exemplified. As oximes, formamidoxime, acetoaldoxime,
Examples include acetoxime, methyl ethyl ketoxime, diacetyl monooxime, cyclohexane oxime and the like. Further, as the lactam, ε-caprolactam,
Examples include δ-valerolactam, γ-butyrolactam, β-propiolactam and the like.

When the epoxy resin is modified with the above-described half-blocked isocyanate, the reaction ratio between the epoxy resin and the half-blocked isocyanate is set so that the functional group equivalent ratio is 1: 2 to 1: 1. It is preferred that both react at a temperature of about ° C.

The water-soluble organic solvent used in the pigment dispersion paste and the resin paste for the main binder used in the present invention is a component for dispersing silica and a pigment component and a pigment dispersion resin or silica and an electrodeposition film-forming resin. is there. For example, a water-soluble organic solvent such as butyl cellosolve and dipropylene glycol monobutyl ether can be used.

The mixing amount of the water-soluble organic solvent is preferably set to 10 to 90% by weight of the total weight of each of the pigment dispersion paste and the resin paste for the main binder, and is preferably set to 20 to 60% by weight. Is more preferred. When the mixing amount of the water-soluble organic solvent is less than 10% by weight, the viscosity of the paste increases, and the decrease in fluidity becomes a serious problem. Conversely, if the content exceeds 90% by weight, there are problems that the non-volatile content (NV) is reduced, the dispersion efficiency is remarkably reduced, and the pigment precipitates in the production process.

The nonvolatile content (NV) of the pigment-dispersed paste and the resin paste for the main binder used in the present invention is usually 20 to 70% by weight, more usually 35 to 60% by weight. Such an NV value can be set arbitrarily.

The pigment-dispersed paste and the resin paste for the main binder used in the present invention may contain various additives usually used in the pigment-dispersed paste or the resin emulsion for the main binder, in addition to the above-mentioned essential components. Examples of such additives include antioxidants, surfactants, plasticizers, and anti-crater agents.

The pigment-dispersed paste used in the present invention can be produced by uniformly mixing and dispersing the above-mentioned various components using a conventional disperser such as a ball mill, a sand grind mill or a continuous disperser.

A pigment-dispersed paste containing silica, a tertiary amine-modified epoxy resin and a quaternary amine-modified epoxy resin is mixed with silica and a pigment component in a water-soluble organic solvent by a conventional method. It is manufactured by further mixing a quaternary amine-modified epoxy resin after dispersing.

The resin paste for the main binder containing silica is prepared, for example, by mixing 0.2 to 1.0 part by weight of an amino-modified epoxy resin with 1 part by weight of silica and adding a water-soluble organic solvent to adjust the viscosity to a predetermined value. 80 ~
After thoroughly mixing the amino-modified epoxy resin warmed to 100 degrees, the mixture is gradually added to a solution of a neutral water such as formic acid or acetic acid in pure water mixed with a stirrer. A homogeneous mixture can be made, and then pure water can be added until the viscosity of the mixture drops sharply.

The electrodeposition coating composition of the present invention is obtained by using the pigment dispersion paste or the resin paste for the main binder containing the silica and the amine-modified epoxy resin produced as described above and a curing agent.

The curing agent used in the electrodeposition coating composition of the present invention is not particularly limited, and a known curing agent which can be a crosslinking agent for the above-mentioned electrodeposited film-forming amine-modified epoxy resin, for example, a blocked isocyanate Compounds and the like can be used.

The electrodeposition coating composition of the present invention is obtained by mixing the above-mentioned pigment-dispersed paste, resin paste for main binder, curing agent and deionized water. In addition, additives known to those skilled in the art, such as other resins, solvents, antioxidants, surfactants, and other auxiliaries commonly used in the electrodeposition step, can be used in the electrodeposition coating composition. May be added as needed within a range that does not impair.

[0041]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to these examples.

"Production Example 1: Tertiary amine-modified epoxy resin" Ethylene glycol monoethyl ether 463 while maintaining 1000 parts by weight of diglycidyl ether of bisphenol A (epoxy equivalent: 910) at 70 ° C. with stirring.
The mixture was dissolved in 100 parts by weight, and 80.3 parts by weight of diethylamine was further added. The mixture was reacted at 100 ° C. for 2 hours to obtain a tertiary amine-modified epoxy resin.

"Production Example 2: Quaternary amine-modified epoxy resin" A reaction vessel equipped with a stirrer, a nitrogen inlet tube, and a cooling tube was prepared, and 174.0 parts of tolylene diisocyanate was charged therein. To this, 33.9 parts of methyl isobutyl ketone was added for dilution, and dibutyltin dilaurate was added to 0.1 part.
Two parts were added. The temperature was raised to 50 ° C., and 131.5 parts of 2-ethylhexanol was dropped and reacted over 2 hours while stirring in a dry nitrogen atmosphere. The reaction temperature was maintained at 50 ° C. to obtain 2-ethylhexanol half-blocked tolylene diisocyanate.

320.0 parts (solid content = 304.0 parts) of this 2-ethylhexanol half-blocked tolylene diisocyanate were mixed with 87.2 parts of dimethylethanolamine.
When the mixture was added to the part at room temperature, heat generation was observed. This is 8
After stirring at 0 ° C. for 1 hour, a 75% aqueous lactic acid solution 117.6 was used.
(Solid content = 88.2 parts), and 39.2 parts of ethylene glycol monobutyl ether were further added. The reaction mixture was stirred at 65 ° C. for about half an hour to obtain a quaternizing agent.

Next, a reaction vessel equipped with a stirrer, a nitrogen introducing pipe, and a cooling pipe was prepared, and Epon 828 (epoxy resin manufactured by Shell Chemical Co., Ltd .: epoxy equivalent = 190) was added to the reaction vessel.
81.2 parts and 289.6 parts of bisphenol A were charged. This was reacted under a nitrogen atmosphere at 150 to 160 ° C. for about 1 hour, and then cooled to 120 ° C. to give 2-ethylhexanol half-blocked tolylene diisocyanate 4
06.4 parts (solid content = 386.1 parts) were added. Further, the mixture was cooled to 85 to 95 ° C. and homogenized, and 496.3 parts (solid content = 421.9) of the quaternizing agent previously produced was added thereto.
Parts) and 71.2 parts of deionized water. The reaction mixture was kept at 80 to 85 ° C. until the acid value became 1 or less, and diluted with 85.6 parts of ethylene glycol monobutyl ether. Thus, a desired quaternary amine-modified epoxy resin having a quaternary ammonium group was obtained.

"Production Example 3: Crosslinking agent" Stirrer, cooling tube,
A reaction vessel equipped with a nitrogen inlet tube and a thermometer was prepared, and 199.1 parts of hexamethylene diisocyanurate was charged therein. This was diluted with 31.6 parts of methyl isobutyl ketone, and 0.2 parts of dibutyltin dilaurate was added. After the temperature was raised to 50 ° C., 87 parts of methyl ethyl ketoxime were added dropwise with stirring in a dry nitrogen atmosphere, and the reaction temperature was maintained at 50 ° C. The temperature was maintained at 70 ° C. until the absorption peak of the isocyanate group in the infrared absorption spectrum disappeared.
5.8 parts and 4.0 parts of n-butanol were added and diluted to obtain a polyurethane crosslinking agent.

[Production Example 4: Amine-modified epoxy resin] A reaction vessel equipped with a stirrer, a cooling pipe, a nitrogen introduction pipe, and a thermometer was prepared, and Epicoat 1001 (bisphenol A type manufactured by Yuka Shell Epoxy Co., Ltd.) was prepared. Epoxy resin: epoxy equivalent = 475) 99.8 parts, Epicoat 1
004 (bisphenol A type epoxy resin manufactured by Yuka Shell Epoxy Co., Ltd .: epoxy equivalent = 950) 850.
2 parts, 55 parts of nonylphenol, 193.3 parts of methyl isobutyl ketone and 4.5 g of benzyldimethylamine
Was added. This was reacted at 140 ° C. for 4 hours to obtain a resin having an epoxy equivalent of 1175.

To this resin were added 69.1 parts of ethylene glycol n-hexyl ether and a methyl isobutyl ketone solution of 2-aminoethylethanolamine methyl isobutyl ketone (35.4% solid content = 78% by weight).
Parts, 26.5 parts of N-methylethanolamine and 37.1 parts of diethanolamine. This was reacted at 120 ° C. for 2 hours to obtain the desired amine-modified epoxy resin.

"Production Example 5: Pigment-dispersed paste containing silica (pigment-dispersed resin: tertiary amine-modified epoxy resin and quaternary amine-modified epoxy resin)" Pigment-dispersed resin of Production Example 1 (tertiary amine-modified epoxy resin) To 206.9 parts by weight, 8.8 parts by weight of glacial acetic acid and 384.3 parts by weight of deionized water were added and dissolved, and then 500 parts by weight of silica and 283 parts of deionized water were added.
After adding 1 part by weight and 50 parts of butycelo, about 1
Stirred for hours. Glass beads were added to this mixture, dispersed in a sand grind mill to a particle size of 15 μm or less, and the glass beads were filtered off. To 1625 parts by weight of this mixture, 95.2 parts by weight to 85.2 parts by weight of the quaternary amine-modified epoxy resin of Production Example 2.
153 parts by weight of a dispersed resin water-doubling with 5.0 parts by weight of 0% acetic acid and 62.8 parts by weight of deionized water (49% NV: paste N
V%) and stirred for 15 minutes to obtain a silica-containing pigment dispersion paste (45.4% NV).

"Production Example 6: Pigment containing silica-dispersed paste (pigment-dispersed resin: tertiary amine-modified epoxy resin)" A pigment obtained by dispersing the following components in a conventional manner using a desktop sand grind mill and pulverizing to a particle size of 5 μm. A dispersion paste (45.4% NV) was produced. 600 parts of the pigment dispersion resin of Production Example 1 (3
Glacial acetic acid was added to 206.9 parts by weight of a tertiary amine-modified epoxy resin.
8 parts by weight and resin dissolved by adding 384.3 parts by weight of deionized water) silica 500 parts deionized water 283 parts butyl cellosolve 50 parts quaternary amine-modified epoxy resin of Production Example 2 153 parts (4
9% NV)

"Preparation Example 7: Pigment-dispersed paste containing silica (pigment-dispersed resin: quaternary amine-modified epoxy resin)" A pigment obtained by dispersing the following components in a conventional manner using a desktop sand grind mill and pulverizing to a particle size of 5 μm. A dispersion paste (45.4% NV) was produced. 295.6 parts of pigment dispersion resin of Production Example 2 (resin obtained by adding 9.8 parts by weight of glacial acetic acid and 121.2 parts by weight of deionized water to 164.6 parts by weight of a quaternary amine-modified epoxy resin) 500 parts of silica Deionized water 574.8 parts Butyl cellosolve 50 parts

"Production Example 8: Pigment-dispersed paste (pigment-dispersed resin: tertiary amine-modified epoxy resin)" The following components were dispersed by a conventional method using a desktop sand grind mill.
Pigment dispersion paste ground to a particle size of 5 μm (42%
NV). Tertiary amine-modified epoxy resin of Production Example 1 (49% NV) 42.13 parts Ion-exchanged water 22.18 parts Clay 25.42 parts Basic silicate 1.94 parts Carbon black 2.67 parts Ion-exchanged water 2 .30 parts Tin paste 3.36 parts

"Preparation Example 9: Resin for Main Binder" 881.5 parts by weight of the resin after the reaction was completed (Preparation Example 4) at 80.degree.
Then, 566.8 parts by weight of the crosslinking agent of Production Example 3 is added thereto, and the mixture is uniformly stirred for about 30 minutes. This was previously added to 376.2 parts by weight of deionized water, 19.5 parts by weight of 90% acetic acid and 26.9 parts by weight of a surfactant (1.5% concentration), and dropped into a homogeneous solution with a stirrer. (NV = 60%) About 3
Stir for 0 minutes. Next, 360 parts by weight of deionized water are added over 10 minutes, and 240 parts by weight are further added over 10 minutes, and then 600 parts by weight of final deionized water are added over 5 to 10 minutes to obtain a main binder resin. Was.

"Production Example 10: Resin paste for silica-containing main binder" 647.8 parts by weight of the crosslinking agent of Production Example 3 were added to 785.8 parts by weight of the amine-modified epoxy resin of Production Example 4 and stirred at 80 ° C for 30 minutes. Next, 90% acetic acid, 1
9.5 parts by weight, 13 parts by weight of a nonionic surfactant and 582.0 parts by weight of the silica-containing paste of Production Example 6 are added to a resin mixture at 80 ° C. while stirring with a stirrer. Next, 1200 parts by weight of deionized water was slowly added in three portions, and the one after the addition was used as a silica-containing main binder resin paste. No desolvation is performed.

Example 1 Electrodeposition Paint Composition An electrodeposition paint composition (20% NV) was produced with the following composition. 7.6 parts of pigment-dispersed paste containing silica of Production Example 6 14.7 parts of pigment-dispersed paste of Production Example 8 36 parts of resin for main binder of Production Example 9 52.6 parts of deionized water

Example 2: Electrodeposition paint composition An electrodeposition paint composition (20% NV) was produced with the following composition. Resin paste for main binder of Production Example 2 25.3 parts Pigment dispersion paste of Production Example 1 18.5 parts Deionized water 60.1 parts

Comparative Example 1: Electrodeposition coating composition The resin obtained in Production Example 9 was used as the resin for the main binder, and the pigment paste used in Production Example 8 was used. An electrodeposition coating composition having a pigment content of 1 part by weight with respect to a resin content of 5 parts by weight was prepared. That N
V was 20%.

Comparative Example 2: Electrodeposition coating composition An electrodeposition coating composition of a comparative example was prepared in the same manner as in Example 1 except that the pigment-dispersed paste containing silica and the pigment-dispersed paste obtained in Production Example 7 were changed. I got

"Evaluation of Matting Effect and Repelling Resistance" The electrodeposition coating compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 2
The bath temperature was adjusted to 28 ° C. in a 1 liter stainless beaker, and zinc phosphate treated 150 mm × 70 mm × 0.1 mm.
An 8 mm steel plate was immersed, a DC voltage of 200 V was applied for 3 minutes using the stainless steel beaker as an anode, and the plate was pulled up and washed with tap water. After rinsing for about 10 minutes in water and then baking at 160 ° C. for 10 minutes, an electrodeposition coating film of the electrodeposition coating composition of the present invention was obtained. The matting degree of the obtained electrodeposition coating film was measured with a spectroreflectometer at 60 ° C. The cissing resistance was evaluated by visually measuring the number of craters generated on the coating film surface (12 cm × 7 cm). The above results are shown in Table 1.

[0060]

[Table 1] ---------------------------------------------- ------------------------- Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 ---------- -------------------------------------------------- ----------- Matting degree 20 30 30 60 30 (Sarasara) ---------------------------- ------------------------------------------- Number of craters 0 0 0 5 0 -------------------------------------------------- --------------------- Paint condition Good Good Good Good Good Good ---------------------- ------------------------------------------------- Implementation The coating films of Examples 1 to 3 had excellent matte coating film appearance without rough skin.

[0061]

According to the present invention, it is possible to provide a matte electrodeposition coating composition having excellent cissing resistance.

Claims (5)

[Claims] 1. A pigment-dispersed paste for electrodeposition paint containing silica, a pigment component, a tertiary amine-modified epoxy resin and a quaternary amine-modified epoxy resin, and a water-soluble organic solvent, and an electrodeposited film-forming amine-modified epoxy resin. And a curing agent. 2. The tertiary amine-modified epoxy resin and 4
The mixing ratio of the primary amine-modified epoxy resin is 1: 1 to 1 respectively.
The electrodeposition coating composition according to claim 1, wherein the ratio is 3: 1. 3. A pigment-dispersed paste for electrodeposition paint containing a pigment component, an amine-modified epoxy resin and a water-soluble organic solvent,
A resin paste for a main binder containing silica, an electrodeposition film-forming amine-modified epoxy resin and a water-soluble organic solvent,
An electrodeposition coating composition comprising a curing agent. 4. A silica, a pigment component, a tertiary amine-modified epoxy resin and a water-soluble organic solvent are mixed to disperse the silica and the pigment component to a predetermined particle size, and then a quaternary amine-modified epoxy resin is added and mixed. 3. A method for producing an electrodeposition coating composition according to claim 1, wherein a pigment-dispersed paste for electrodeposition coating is produced, and an amine-modified epoxy resin capable of forming an electrodeposition film and a curing agent are mixed therewith. . 5. A solution obtained by mixing silica, an amine-modified epoxy resin, and a water-soluble organic solvent to disperse silica to a predetermined particle size, further mixing an amine-modified epoxy resin, and then mixing water with a neutralizing acid. To prepare a resin paste for a main binder containing silica, which contains a pigment component, an amine-modified epoxy resin, and a water-soluble organic solvent, a pigment dispersion paste for an electrodeposition paint, and an electrodeposition film-forming amine. 4. The method for producing an electrodeposition coating composition according to claim 3, wherein the composition is mixed with a modified epoxy resin curing agent.