JPH0255466B2 - - Google Patents

Description

[Detailed description of the invention]

Background and Problems of the Invention Electrodeposition paints are widely used as undercoats with anticorrosive properties because of their workability regardless of shape and their safety. Electrodeposition paints have a form in which resin is dispersed or dissolved in water as a medium, so controlling its stability and throwing power through energization is necessary to stabilize the coating line. Regarding its performance as a coating film, coating films with high film thickness and high performance physical properties are desired, particularly in fields where high corrosion resistance and chipping resistance are required, such as automotive coating systems. In addition, as consumers have recently become more conscious of high-quality products, there has been a strong desire for high-quality paint films, and there is a strong need for paint films that have higher definition and higher gloss than ever before. In conventional electrodeposition paints, pigments are used to adjust the fluidity of the coating film during curing. That is, in systems that do not contain pigments, the fluidity of the coating film during curing is generally too high, and sagging, sagging, etc. are likely to occur on the end surfaces. However, the method of adjusting the fluidity of the coating film during curing using pigments cannot of course be applied to clear coatings, and since the pigment itself is not a film-forming resin component, it may be difficult to adjust the fluidity of the coating film depending on the amount added. Other properties such as workability, strength of the coating film, and water resistance were adversely affected, and it was difficult to sufficiently control the fluidity of the coating film during curing. Therefore, an object of the present invention is to provide an electrodeposition coating material that can control the fluidity of the coating film during curing without adversely affecting the electrodeposition workability or the performance of the coating film. SOLUTION The above problem is solved by using internally crosslinked micro resin particles of a certain particle size and crosslinking degree range to control the fluidity of the coating film during curing of the electrodeposition paint. Therefore, the present invention provides (a) an aqueous dispersion of an aqueous resin that can be electrodeposited, and (b) particles having a particle size of 0.01 to 20 μ and a degree of crosslinking that are uniformly dispersed in the aqueous dispersion of the aqueous resin. 0.01〜
Provided is an electrodeposition coating composition characterized in that it contains 5.05 mmol/g of internally crosslinked fine resin particles as an essential component. By adding the fine resin particles, excessive fluidity during curing of the coating film is controlled, and the occurrence of sagging, sagging, etc. on the end surface is eliminated. However, since the fine resin particles are stably dispersed in the electrodeposition paint bath, they do not impair the workability of electrodeposition, and since they become part of the film-forming resin component of the paint, they do not reduce the performance of the paint film. This has the effect of improving performance. Detailed Discussion Electrodepositable Aqueous Resins The present invention is applicable to both cationic and anionic electrodeposition coatings. The aqueous electrodepositable resin (base resin) is generally a film-molding resin having functional groups that provide the charge and hydrophilicity necessary for electrodeposition. They are classified into aqueous solution type, dispersion type, emulsion type, and suspension type, mainly depending on their form when dispersed in water, and herein they are collectively referred to as aqueous resin. Various types of water-based resins are known for use in electrodeposition paints, and any of these known water-based resins can be used in the present invention. The water-based resin used in anionic electrodeposition paints has anionic functional groups such as carboxyl groups in order to give the resin the negative charge and hydrophilicity necessary for electrodeposition. Typical such resins are maleated natural or synthetic drying oils, maleated polybutadiene, half esters, half amides thereof, and the like. The water-based resin used in cationic electrodeposition paints has cationic functional groups such as amino groups to give it positive charge and hydrophilicity. Various types of resins such as epoxy resins, polyether resins, polyester resins, polyurethane resins, polyamide resins, and polybutadiene resins are known as examples of such resins. Depending on the mechanism of the curing reaction, these resins can be of the self-crosslinking type, in which the resin itself is cured by radical polymerization or oxidative polymerization, or in combination with a curing agent, such as a melamine resin or a block polyisocyanate compound. There are curing agent types that harden when used in combination, and types that use both in combination. Furthermore, according to the type of curing energy, it can be classified into types such as room temperature curing, heat curing, and radiant energy curing such as ultraviolet rays and electron beams. Furthermore, for the purpose of improving coating film performance, resins that do not have functional groups that impart charge and hydrophilicity, such as epoxy acrylate resins, are used in combination with the hydrophilic resins in the form of emulsions. In the present invention, the aqueous resin includes such a curing agent and a resin combination system having no hydrophilic functional group. Such electrodepositable aqueous resins are well known to those skilled in the art and do not require further explanation as such do not form part of the present invention. Micro resin particles Various methods have been proposed to produce micro resin particles, one of which involves suspension polymerization or polymerization of an ethylenically unsaturated monomer with a crosslinkable comonomer in an aqueous medium. This method uses emulsion polymerization to create a dispersion of fine resin particles, and then removes water by solvent replacement, azeotropy, centrifugation, drying, etc. to obtain fine resin particles. Ethylenically unsaturated monomers and crosslinkable copolymers are co-coated in organic solvents or non-aqueous organic solvents that dissolve monomers but do not dissolve polymers, such as high SP organic solvents such as esters, ketones, and alcohols. This is a method called the NAD method or precipitation method, in which the resulting fine resin particle copolymer is dispersed through polymerization. The fine resin particles of the present invention may be produced by any of the above methods. Examples of ethylenically unsaturated monomers include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)allylate, isobutyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. Alkyl esters of acrylic acid or methacrylic acid and other monomers having ethylenically unsaturated bonds that can be copolymerized with them, such as styrene,
Examples include α-methylstyrene, vinyltoluene, t-butylstyrene, ethylene, propylene, vinyl acetate, vinyl propionate, acrylonitrile, methacrylonitrile, dimethylaminoethyl (meth)acrylate, and the like. Two or more types of these monomers may be used. The crosslinkable copolymerizable monomer is a monomer having two or more radically polymerizable ethylenically unsaturated bonds in the molecule and/or two types of ethylenically unsaturated monomers each carrying mutually reactive groups. Contains group-containing monomers. Examples of monomers having two or more radically polymerizable ethylenically unsaturated groups in the molecule include polymerizable unsaturated monocarboxylic acid esters of polyhydric alcohols;
Examples include polymerizable unsaturated alcohol esters of polybasic acids and aromatic compounds substituted with two or more vinyl groups, examples of which include the following compounds. Ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol dimethacrylate acrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate,
Pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol dimethacrylate,
Glycerol diacrylate, glycerol allyloxy dimethacrylate, 1,1,1-trishydroxymethylethane diacrylate, 1,1,
1-trishydroxymethylethane triacrylate, 1,1,1-trishydroxymethylethane dimethacrylate, 1,1,1-trishydroxymethylethane trimethacrylate, 1,1,
1-trishydroxymethylpropane diacrylate, 1,1,1-trishydroxymethylpropane triacrylate, 1,1,1-trishydroxymethylpropane dimethacrylate, 1,
1,1-trishydroxymethylpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate and divinylbenzene. In addition, two groups each carrying a group that can react with each other
Examples of monomers having ethylenically unsaturated groups include epoxy group-containing ethylenically unsaturated monomers such as glycidyl acrylate and glycidyl methacrylate, and carboxyl group-containing ethylenically unsaturated monomers such as acrylic acid, methacrylic acid, and croton. The most typical example is amine and carbonyl, epoxide and carboxylic acid anhydride, amine and carboxylic acid chloride, and alkylene imine. Various compounds have been proposed, such as carbonyl and organoalkoxysilane, carboxyl and hydroxyl, and isocyanate and hydroxyl, and the present invention broadly encompasses these. Fine resin particles produced in an aqueous medium or a non-aqueous organic medium are isolated by a method such as filtration, spray drying, or freeze drying, and then left as is or pulverized to an appropriate particle size using a mill or the like. Furthermore, the synthesized dispersion liquid can be used as it is, or the medium can be replaced by solvent replacement. Generally, it is desirable to control the particle size of the particles obtained by the polymerization method. 0.01
For particles of ~0.6 μ, emulsion polymerization method and NAD method are
Precipitation polymerization is suitable for particles of 0.2-2μ. The degree of crosslinking of the internally crosslinked fine resin particles is determined by the molar fraction of the crosslinkable comonomer in the monomer mixture. Fine resin particles with a degree of crosslinking less than 0.01 mmol/g have little effect on controlling the fluidity of the coating film during baking, while those with a degree of crosslinking exceeding 5.05 mmol/g are difficult to put into practical use. In order to maintain a stable dispersion state in the paint and the electrodeposition bath, the fine resin particles themselves preferably have ionizable groups of the same polarity as the aqueous resin that is the base resin. In other words, anionic groups such as carboxyl groups and sulfonic acid groups are used in anionic electrodeposition, and amino groups and quaternary groups are used in cationic electrodeposition.
It is preferable to carry a cationic group of a grade ammonium group. To achieve this, monomers having an ethylenically unsaturated bond and a carboxyl group, such as acrylic acid and methacrylic acid, and monomers having an ethylenically unsaturated bond and a basic group,
For example, dimethylaminoethyl (meth)acrylate, vinyl pyridine, etc. are added to the monomer mixture during the synthesis of minute resin particles, or monomers are added to the monomer mixture using an initiator that provides a cationic end during the synthesis of minute resin particles. There is a method of polymerizing the mixture. If the polymer itself that makes up the micro resin particles is non-polar, use an appropriate emulsifier during synthesis of the micro resin particles, especially oligosoaps, polysoaps, or reactive emulsifiers that have amphoteric ionic groups to stably disperse the micro resin particles. You can also do so. These emulsifiers having zwitterionic groups were disclosed in Japanese Patent Application Laid-Open No.
56-24461, 57-21927, 57-40522, etc. The fine resin particles are obtained by polymerizing the above-mentioned monofunctional ethylenically unsaturated monomer and crosslinkable monomer by solution polymerization or bulk polymerization, crushing the resulting polymer, and then classifying it to a predetermined particle size. You can also get it. As another method, in the case of fine resin particles such as epoxy resin, melamine resin, alkyd resin, etc., a liquid resin is emulsified and dispersed in water, and the emulsified resin dispersion is spray-dried to obtain a fine resin having a predetermined particle size. Alternatively, if the resin is solid, it can be crushed and classified to form a predetermined microscopic resin. Electrodeposition Coating Composition The electrodeposition coating composition of the present invention contains the electrodepositable aqueous resin and the fine resin particles as essential components. The ratio of aqueous resin and fine resin particles is 1 to 50% by weight of the former as solid content.
It is. If the amount of fine resin particles added is too small, there will be no effect, and if it is too large, the stability of the paint and the workability of electrodeposition will be impaired. Depending on the type of aqueous resin used, it may also contain auxiliary curing agents such as melamine resin, benzodiguanamine resin, phenolic resin, blocked polyisocyanate compounds, and metal compounds such as manganese, cobalt, copper, lead, and tin as catalysts. be able to. These components are dispersed in an aqueous medium containing a base for anionic electrodeposition and an acid for cationic electrodeposition. These acids and bases are used to neutralize the electrodepositable water-soluble resin. Examples of the base used for neutralization include ammonia, diethanolamine, triethanolamine, methylethanolamine, diethylamine,
Examples include morpholine and potassium hydroxide. As the acid, phosphoric acid, acetic acid, propionic acid, lactic acid, etc. are used. The aqueous medium is water or a mixture of water and a water-miscible organic solvent. If necessary, the aqueous medium may contain a water-immiscible organic solvent. Examples of water-miscible organic solvents include ethyl cellosolve, propyl cellosolve, butyl cellosolve, ethylene glycol dimethyl ether, diacetone alcohol, 4-methoxy-4-methylpentanone-2, methyl ethyl ketone, and the like. Examples of water-immiscible organic solvents include xylene, toluene, methyl isobutyl ketone, and 2-ethylhexanol. A pigment can be obtained from the coating composition of the present invention. Examples include titanium dioxide, red iron,
There are coloring pigments such as carbon black, extender pigments such as aluminum silicate and precipitated barium sulfate, and antirust pigments such as aluminum phosphomolybdate, strontium chromate, basic lead silicate, and lead chromate. The coating composition of the present invention has a non-volatile content of the coating of 10 to 10%.
Adjust to about 20%, electrodeposit to a dry film thickness of 15 to 30μ,
Depending on the type of resin, it can be cured by room temperature curing, heat curing, ultraviolet curing, electron beam curing, etc. Production examples, examples and comparative examples of the present invention are shown below. Parts and percentages in these examples are by weight. Production example 1 Production of anionic micro resin particles In a two-colben equipped with a stirrer, nitrogen inlet tube, temperature control device, condenser, and decanter, 184 parts of bishydroxyethyl taurine, 130 parts of neopentyl glycol, 236 parts of azelaic acid, and anhydrous Charge 186 parts of phthalic acid and 27 parts of xylene and raise the temperature. Water produced by the reaction is removed by azeotropic reflux with xylene. The temperature is increased over 2 hours from the start of reflux.
Heat to 190°C, continue stirring and dehydration until the acid value equivalent to carboxylic acid reaches 145, and cool to 140°C. Next, while maintaining the temperature of the reaction solution at 140° C., 314 parts of “Cardilla E10” (Versatellite glycidyl ester manufactured by Shell) was added dropwise over 30 minutes, and stirring was continued for 2 hours to complete the reaction. The resulting polyester resin has an acid value of 59, a hydroxyl value of 90, and an Mn of 1054.
It was hot. 1 equipped with a stirrer, cooler, and temperature control device
In a reaction vessel, add 306 parts of deionized water, 45 parts of the polyester resin obtained above, and dimethylethanolamine.
Add 4.5 parts of azobiscyanovaleric acid and dissolve it while stirring while maintaining the temperature at 80°C. To this, add 4.5 parts of azobiscyanovaleric acid, 45 parts of deionized water, and 4.3 parts of dimethylethanolamine.
Add the dissolved material to the solution. Next, 70.7 parts of methyl methacrylate, n-butyl acrylate
A mixed solution consisting of 94.2 parts of styrene, 70.7 parts of styrene, 30 parts of 2-hydroxyethyl acrylate, and 4.5 parts of ethylene glycol dimethacrylate was added dropwise over 60 minutes. After the addition, a solution of 1.5 parts of azobiscyanovaleric acid dissolved in 15 parts of deionized water and 1.4 parts of dimethylethanolamine was added, and the mixture was heated at 80°C.
When stirring was continued for 60 minutes, an emulsion with a nonvolatile content of 45% and a particle size of 43 nm was obtained. Crosslinking degree 0.084
mmol/g. Production Example 2 Production of cationic micro resin particles As a monomer mixture, 55.7 parts of styrene, 41.7 parts of methyl methacrylate, 13.9 parts of n-butyl acrylate, and ethylene glycol dimethacrylate.
83.5 parts dimethylaminopropyl methacrylate
A particle size of 51 nm and a degree of crosslinking of 1.562 m were obtained by the same operation as in Production Example 1 except that 5.6 parts were used.
An emulsion of fine resin particles of mol/g was obtained.
Non-volatile content: 45% Production Example 3 Production of anionic micro resin particles Using the equipment used to produce the modified polyester resin in Production Example 1, 100 parts of ethylene glycol monomethyl ether was charged, and the temperature was raised to 100°C and maintained. Prepare two dropping funnels, put 100 parts of ethylene glycol monomethyl ether into one, and dissolve 75 parts of N-methyl-N-(vinylbenzol)taurine in the funnel. At this time, a small amount of dimethylethanolamine is added as a solubilizing agent. Furthermore, in one dropping funnel, 50 parts of 2-hydroxyethyl acrylate, 10 parts of acrylic acid, 110 parts of methyl methacrylate, 110 parts of styrene, 145 parts of n-butyl acrylate, and lauryl mercaptan were added.
Mix 10 parts and dissolve 10 parts of azobisisobutyronitrile. The contents of the two dropping funnels are added dropwise over a period of 120 minutes, after which the temperature is maintained at 100°C and stirring is continued for 60 minutes. Next, the solvent of this resin solution was removed using a rotary evaporator, and the Mn was reduced to a resin solid content of 96%.
4500 acrylic resin was obtained. 306 parts of deionized water, 18 parts of the acrylic resin obtained above, and 2.6 parts of dimethylethanolamine were placed in a reaction vessel 1 equipped with a stirrer, a cooling tube, and a temperature control device, and the temperature was raised to 80°C while stirring. . After the contents have dissolved, maintain the temperature at 80°C while stirring, and add 4.8 parts of azobiscyanovaleric acid, 4.56 parts of dimethylethanolamine, and deionized water.
Prepare an aqueous solution consisting of 48 parts, then add styrene.
A mixed solution consisting of 74.7 parts of methyl methacrylate, 74.7 parts of methyl methacrylate, 99.6 parts of n-butyl acrylate, 30 parts of 2-hydroxyethyl acrylate, and 3 parts of ethylene glycol dimethacrylate was added dropwise over 60 minutes. After dropping, add 1.2 parts of azobiscyanovaleric acid and dimethylethanol-amine at the same temperature.
Add a mixed aqueous solution consisting of 1.14 parts and 12 parts of deionized water and continue stirring for 60 minutes until the particle size is 132 nm.
An emulsion was obtained. Nonvolatile content 45%, degree of crosslinking
0.054 mmol/g. Production Example 4 Production of cationic micro resin particles As a monomer mixture, 26.6 parts of styrene, 79.8 parts of methyl methacrylate, 53.2 parts of n-butyl acrylate, and ethylene glycol dimethacrylate.
53.2 parts of ethyl acrylate, 53.2 parts of ethyl acrylate, and 16.0 parts of diethylaminoethyl acrylate.
A fine resin emulsion with a diameter of 146 nm and a degree of crosslinking of 0.953 mmol/g was obtained. Non-volatile content 45% Production Example 5 Production of anionic micro resin particles The equipment used in Production Example 1 to produce modified polyester resin was used to produce sodium salt of taurine.
Add 73.5 parts, 100 parts of ethylene glycol, and 200 parts of ethylene glycol methyl ether, and heat while stirring to raise the temperature to 120. After the contents reach a uniform state of dissolution, Epicote 1001 (manufactured by Ciel Chemical Co., diglycidyl ether type epoxy resin of bisphenol A, epoxy equivalent: 470)
470 parts and ethylene glycol monomethyl ether
A solution consisting of 400 parts is added dropwise over a period of 2 hours. After dripping
Stirring and heating were continued for 20 hours to complete the reaction, yielding 518 parts of modified epoxy resin. This resin had an acid value of 49.4 by KOH titration, and a sulfur content of 2.8% by fluorescent X-ray analysis. In a reaction vessel equipped with a stirrer, a cooling tube, and a temperature control device, 306 parts of deionized water, 7.5 parts of the modified epoxy resin obtained above, and 1.0 parts of dimethylethanolamine were added.
The temperature was raised to 80℃ while stirring. After the contents have dissolved, maintain the temperature at 80℃ while stirring, and add azobiscyanovaleric acid to this.
4.8 parts of dimethylethanolamine and 48 parts of deionized water, followed by 80 parts of styrene, 80 parts of methyl methacrylate, n-
A liquid mixture consisting of 107 parts of butyl acrylate, 30 parts of 2-hydroxyethyl acrylate, and 3 parts of ethylene glycol dimethacrylate was added dropwise over 60 minutes. After dropping, a mixed aqueous solution consisting of 1.2 parts of azobiscyanovaleric acid, 1.14 parts of dimethylethanolamine, and 12 parts of deionized water was added at the same temperature, and stirring was continued for 60 minutes to determine the particle size.
An emulsion of 0.112μ was obtained. Non-volatile content 45%, degree of crosslinking 0.051 mmol/g Production example 6 Production of anionic micro resin particles In a glass reaction flask equipped with a stirrer, Dimroth, thermometer and air inlet tube.
60 parts succinic anhydride, 440 parts Praxel FM−
5 (a 5:1 molar adduct of ε-caprolactone and 2-hydroxyethyl methacrylate, manufactured by Daicel Chemical Industries, Ltd.) and hydroxyl monomethyl ether in an amount of 500 ppm based on the total amount charged were charged at once. Then, while sucking air through the inlet pipe, the internal temperature
The reaction was carried out by stirring at 150 °C for 60 minutes.
After the reaction was completed, when the product was cooled to room temperature, a small amount of unreacted acid anhydride crystals precipitated, which were removed by filtration to obtain a semi-solid product with an acid value of 70. Into the same reaction apparatus used for the polymerization reaction in Production Example 1, 280 parts of deionized water was also charged in advance, and then 20 parts of the 100% neutralized dimethylethanolamine of the reactive monomer synthesized above, Methyl methacrylate 16 parts, n-butyl acrylate 20 parts
A mixture of 14 parts of ethylene glycol dimethacrylate and 30 parts of styrene was added dropwise to the flask using a dropping funnel while stirring at an internal temperature of 80° C. for 2 hours. Further, as an initiator, 1 part of ammonium persulfate salt dissolved in 20 parts of ion-exchanged water was added dropwise at the same time as the above-mentioned mixed monomers, thereby carrying out emulsion polymerization. The reaction product had a solids concentration of 25% by weight, and the emulsion particle diameter was 76 nm as measured by laser light scattering. Crosslinking degree 0.0884m
mol/g Example 1 Production of urethane-based cationic electrodeposition paint EPON1001 with an epoxy equivalent of 485,
Charge 970 parts and 265 parts of polycaprolactone diol (trade name PCP0200, Union Carbide Corporation). PCP0200 is thought to have become a polymer with a molecular weight of about 543 through a ring-opening reaction of ε-caprolactone with ethylene glycol. This was heated to 100℃ under a nitrogen atmosphere,
Add 0.46 parts of benzyldimethylamine. The reaction mixture is further heated to 130°C and maintained at this temperature for about 1.5 hours. This batch was cooled to 110°C and 110 parts of methyl isobutyl ketone was added, followed by 39.8 parts of a 73% solution of methyl isobutyl diketimine in nonvolatile diethylene triamine, methyl isobutyl ketone,
Add another 100 parts of methyl isobutyl ketone.
Continue cooling until the batch temperature reaches 70℃, and at this temperature, add 53.1 parts of diethylamine and raise the bath temperature to 120℃.
After holding for 3 hours, remove. This is called the first liquid. Non-volatile content: 85% In a separate reactor, 218 parts of 2-ethylhexanol was added to 291 parts of an 80/20 (weight ratio) mixture of 2,4-/2,6-toluene diisocyanate under a dry nitrogen atmosphere while stirring. and cooled externally to bring the reaction temperature to 38
℃ to prepare the polyurethane crosslinker. This is kept at 38° C. for an additional half hour, then heated to 60° C., and 75 parts of trimethylolpropane are added, followed by 0.08 parts of dibutyltin dilaurate catalyst. After the initial exotherm, the batch is held at 121° C. for 1 hour until substantially all of the isocyanate residues have been consumed as determined by infrared scanning or the like. This batch is further diluted with 249 parts of ethylene glycol monoethyl ether.
Add this to the second liquid. Non-volatile content: 70% Next, 576 parts of the first liquid, 217 parts of the second liquid and 13.2 parts of dibutyltin dilaurate catalyst were mixed, and glacial acetic acid
Neutralize with 12.3 parts and slowly dilute with 705.5 parts of deionized water. To this was added 39 parts of ethylene glycol monohexyl ether, 1880 parts of deionized water, and 145 parts of the fine resin dispersion of Production Example 2, resulting in a solid content of approximately 20%.
(Solid content of fine resin particles in the paint bath is approximately 2%). A dull steel plate treated with zinc phosphate is immersed in a paint bath, and the coating voltage is 60V with the object to be coated as the cathode.
After electrodeposition for 3 minutes, washing with water and baking at 175°C for 30 minutes, a coated plate with a film thickness of 2 μm was obtained. Example 2 Production of cationic electrodeposited enamel Part 1 An acid salt of an organic tertiary amine is prepared according to the following recipe.

Table: Using a suitable reaction vessel, add 2-ethylhexanol semi-capped diisocyanate to dimethylethanolamine at room temperature. The mixture becomes exothermic and is stirred at 80°C for 1 hour. Next, add lactic acid and then add butyl cellosolve. The reaction mixture is stirred at 65° C. for about half an hour to obtain the desired quaternizing agent. Part 2 A dissolving resin vehicle containing the reactive product of the epoxy-containing organic compound and the blocked isocyan group-containing organic amine described in Part 1 is prepared according to the following recipe.

[Table] Epon 829 and Bisphenol A are charged into a suitable reactor and heated to 150-160°C under nitrogen atmosphere. This is an initial exothermic reaction. Reaction mixture 150-160
After being subjected to a thermal reaction at ℃ for about 1 hour and then cooled to 120℃,
Add 2-ethylhexanol semi-capped toluene diisocyanate. The temperature of the reaction mixture is maintained at 110-120°C for about 1 hour and then the butyl cellosolve is added. Then cool to 85-95℃, homogenize,
Add water and then add quaternizing agent. The temperature of the reaction mixture is maintained at 80-85°C until the acid number is 1. Part 3 Prepare a pigment paste using the resin vehicle from Part 2 according to the following recipe.

[Table] 1024 parts of the resin vehicle of Part 2 are diluted with 241 parts of butyl cellulosolve and 1122 parts of deionized to give a solids content of 30%. Next, 1,666 parts of kaolin, 204.4 parts of lead silicate, and 71.4 parts of dibutyltin oxide are added, and the mixture is mixed and stirred using a disperser for about 1 hour. After glass beads are added to this mixture, they are dispersed in a sand mill to a particle size of 20 μm or less, and the glass beads are separated to obtain a pigment paste. Non-volatile content 55% 576 parts of the first liquid of Example, 217 parts of the second liquid of Example 1
and 13.2 parts of divibltin dilaurate, neutralized with 12.3 parts of glacial acetic acid, and diluted with 705.5 parts of deionized water. After adding 39 parts of ethylene glycol monohexyl ether and 1880 parts of deionized water, 360 parts of the pigment paste prepared above, 630 parts of deionized water, and 190 parts of the fine resin particle dispersion of Production Example 4 were added.
A cationic electrodeposited enamel with a solid content of about 2% of fine resin particles in the paint bath is obtained. The electrodeposition coating conditions were the same as in Example 1. However, the coating voltage is 100V Example 3 Production of polybutadiene-based cationic electrodeposition paint Part 1 Nisseki Polybutadiene B-2000 (number average molecular weight
2000, 1,2 bonds (65%) was epoxidized using peracetic acid to produce epoxidized polybutadiene with an oxirane oxygen content of 6.4%. After charging 1000 g of this epoxidized polybutadiene and 354 g of ethyl cellosolve into two autoclaves, 62.1 g of dimethylamine was added, and the mixture was heated to 150°C.
The reaction was carried out for 5 hours. After distilling off the unreacted amine, it was cooled to 120°C, a mixture of 79.3g of acrylic acid, 7.6g of hydroquinone and 26.4g of ethyl cellosolve was added, and the reaction was further carried out at 120°C for 3 hours and 45 minutes to obtain the resin solution (A). Manufactured. The amine value of this product is 85.2 mmol/100g, and the acid value is 100 mmol/100 g.
100g and the solids concentration was 75.0% by weight. Part 2 1000g of bisphenol type epoxy resin (trade name Epicote 1004 manufactured by Yuka Ciel Epoxy Co., Ltd.) with an epoxy equivalent of 950 was mixed with 343g of ethyl cellosolve.
Dissolved in acrylic acid 76.3g, hydroquinone 10
5 g and N,N-dimethylaminoethanol
g was added, heated to 100°C, and reacted for 5 hours to synthesize a resin solution (B). Solid content concentration 75% by weight Part 3 Nisseki Polybutadiene B-1000 (number average molecular weight
1000, 1,2 bonds 60%) 1000g maleic anhydride
265.8 g, xylene 10 g, and Antigen 6C (Sumitomo Chemical brand name) 1 g were placed in two separable flasks equipped with a reflux condenser and heated at 190°C under a nitrogen stream for 50 minutes.
Allowed time to react. Next, unreacted maleic anhydride and xylene were distilled off under reduced pressure, and the acid value was 214 mmol/100.
g of maleated polybutadiene was synthesized. Next, 1000 g of maleated polybutadiene and 212.4 g of ethyl cellosolve were charged into a two-separable flask equipped with a reflux condenser and reacted with stirring at 120° C. for 2 hours to produce a half-esterified product (C) of maleated polybutadiene. Solid content concentration 98% by weight Part 4 400g of (A) manufactured in Part 1, manufactured in Part 2
After 240 g of (B) and 19.2 g of (C) prepared in step 3 were mixed until homogeneous, 8.1 g of acetic acid was added and thoroughly stirred for neutralization. 1835 g of deionized water was gradually added to this varnish to obtain an emulsion with a solids concentration of about 20%. Thereafter, 156 g of the fine resin dispersion of Production Example 2 was added to prepare an aqueous solution with a solid content concentration of approximately 20% (solid content of fine resin particles in the paint bath was approximately 3%). Using the above electrodeposition coating solution, cathodic deposition coating was carried out at 100 V for 3 minutes using the carbon electrode as the anode and the zinc phosphate treated plate as the cathode. Baking at 175℃ x 30 minutes.
The test results are shown in Table-1. Example 4 Polybutadiene-based cationic electrodeposited enamel Part 1 Quaternary ammonium group-containing resin E1800-6.5 (manufactured by Nippon Petrochemical Co., Ltd., epoxidized polybutadiene) 1000 g Butyl cellosolve 349 g Dimethylamine 46 g 50% lactic acid 138 g Deionized water 473 g Phenyl Grillcidyl Ether 117g After charging epoxidized polybutadiene E1800-6.5 and butyl cellosolve into an autoclave,
Dimethylamine was added and reacted at 150°C for 5 hours.
After distilling off unreacted amine, it was cooled to 60°C.
80℃ after adding a mixture of 50% lactic acid and deionized water
Stir and keep warm for 30 minutes. After that, phenyl glycidyl ether was added, the temperature was raised to 110℃, and while stirring and keeping warm, the acid value of the contents was measured by the usual method using phenolphthalene as an indicator and alcoholic KOH as a standard solution, and the acid value was 0.1 or less. After allowing the reaction to occur, production is terminated. Non-volatile content 55% Part 2 Pigment paste part 1 varnish 231g Deionized water 315g Carbon black 16g Titanium oxide 92g Kaolin 220g Basic lead silicate 58g After adding deionized water to the varnish of Part 1 and dissolving it, add the pigment and use a disper. Stir and mix for about 1 hour. After glass beads are added to this mixture, they are dispersed in a sand mill to a particle size of 20 μm or less, and the production is completed after the glass beads are separated. Non-volatile content 55% Part 3 Electrodeposited enamel 400g of (A) manufactured in Part 1 of Example 3, Example 3
240g of (B) produced in Part 2 of Example 3, Part 3 of Example 3
After mixing 19.2 g of (C) produced in step 1 until homogeneous, 8.1 g of acetic acid was added and thoroughly stirred to neutralize.
1835 g of deionized water was gradually added to this varnish to obtain an emulsion with a solids concentration of about 20%. after that,
360 g of the paste from Part 2, 140 g of the fine resin dispersion from Production Example 4, and 260 g of deionized water were uniformly stirred to prepare an enamel electrodeposition bath (solid content of fine resin particles in the paint: about 2%). Using this electrodeposition bath, electrodeposition (150V x 3 minutes) and curing (baking at 175°C x 30 minutes) were carried out under the same conditions as in Example 1.
Table 1 shows the performance of the coated film. Example 5 Production of polybutadiene-based anionic electrodeposition paint Part 1 Nisseki Polybutadiene B-1500 (*1) 1000g Antigen 6C (*2) 10g Maleic anhydride 250g Deionized water 20g Diethylamine 0.5g Propylene glycol 100g Ethyl cellosolve 340g (* 1) Manufactured by Nippon Petrochemical Co., Ltd.; Mn1500, vinyl 65
%, trans 14%, cis 16% (*2) Manufactured by Sumitomo Chemical Co., Ltd.; N-methyl-N′-(1,
3-dimethylbutyl), p-phenylenediamine Charge 1000g of Nisseki Polybutadiene B-1500 into a 2-kolben equipped with a cooling tube, and add 10g of Antigen 6C and 250g of maleic acid. The addition reaction of maleic acid to polybutadiene is carried out while stirring and maintaining the internal temperature at 190 to 200°C. Approximately 5 hours after the temperature was raised, it was confirmed that the reaction had completed due to the dimethylaniline color reaction. After that, the internal temperature was cooled to 100℃, and a mixture of 20 g of deionized water and 0.5 g of diethylamine was added to the
Drop in 30 minutes. Further, stirring was continued for about 1 hour after the completion of the dropwise addition, and the acid value was confirmed to be 140. Thereafter, 100 g of propylene glycol was added and reacted at 110° C. for 3 hours, and the total acid value was confirmed to be 125. Then add 340g of ethyl cellosolve and heat at 80°C.
After stirring for about 1 hour, the synthesis was completed. Nonvolatile content 80% Part 2 Epotote YD-014 (*3) 950g Ethyl cellosolve 240g Hydroquinone 10g Acrylic acid 65g Dimethylbenzylamine 5g (*3) Manufactured by Tobu Kasei Co., Ltd., epoxy resin, epoxy equivalent 950, 2 Kolben with cooling tube Epotote YD-014
Add 950g and 240g of ethyl cellosolve and gradually
Uniformly dissolve YD-014 while stirring to 120℃. Then add 10 g of hydroquinone, and further add 65 g of acrylic acid and 5 g of dimethylbenzylamine. After reacting at 120°C for 4 hours, it was confirmed that the post-acid value was 1 or less. Non-volatile content 80% Part 3 Part 1 varnish 125g, Part 2 varnish 75g,
Collect 40g of butylated melamine (50% nonvolatile content) and 40g of resol type phenolic resin (50% nonvolatile content), add 2g of nonionic surfactant and 3g of cobalt naphthenate, stir evenly, and then add 13g of triethylamine. Next, 707 g of deionized water was gradually added and stirred uniformly to dissolve it, and 60 g of the fine resin particle dispersion of Production Example 1 was added, and the solid content concentration was approximately 20% (the solid content of fine resin particles in the paint was approximately 3 %)
A paint bath was prepared. A dull steel plate treated with zinc phosphate was immersed in a paint bath, and electrodeposition was applied at 150V for 3 minutes using the object to be coated as an anode. Thereafter, the surface of the object to be coated was washed with water and baked in a baking oven at 140°C for 30 minutes to obtain a coated plate with a film thickness of about 20μ. The results of testing the performance of the obtained coating film are shown below.
Shown in 1. Example 6 Production of polybutadiene-based anionic electrodeposited enamel Part 1 Pigment enamel 125 g of the varnish from Example 5, Part 1 was collected, 13 g of triethylamine was added thereto, and then 250 g of deionized water was gradually added to dissolve uniformly. The varnish has a non-volatile content of 26%. Next, 150g of titanium dioxide, 50g of lead silicate, 25g of strontium chromate, and 25g of carbon black.
Add g and stir with a disperser for about 1 hour. After glass beads are added to this mixture, they are dispersed in a sand mill to a particle size of 20μ or less, and after the glass beads are separated, the production is completed. Non-volatile content 55% Part 2 Electrodeposited enamel 125g of varnish of Example 1, varnish of Part 2
75g, butylated melamine (50% non-volatile content) 40g,
Resol type phenolic resin (non-volatile content 50%) 40g
2 g of nonionic surfactant and 3 g of cobalt naphthenate were added to this, and after stirring uniformly, 13 g of triethylamine was added, and then deionized water was added.
Gradually add 707g and stir evenly to dissolve.
Next, 125g of pigment paste from Part 1, deionized water
220 g and 80 g of the fine resin particle dispersion of Production Example 3 were uniformly stirred to prepare an enamel electrodeposition bath (solid content of fine resin particles in the paint was about 3%). Table 1 shows the performance of the coating film electrodeposited and cured using this electrodeposition bath under the same conditions as in Example 5.
Coating voltage: 150 V x 3 minutes Example 7 The same procedure as in Example 6 was carried out except that the fine resin particle dispersion of Production Example 3 in Example 6 was changed to the fine resin particle dispersion of Production Example 5. Example 8 The same procedure as in Example 6 was carried out except that the fine resin particle dispersion of Production Example 3 in Example 6 was changed to the fine resin particle dispersion of Production Example 6. Comparative Example 1 The same procedure as Example 1 was carried out except that the fine resin particle dispersion of Production Example 2 of Example 1 was not added. (However, the coating voltage was 50 V) Comparative Example 2 The same procedure as in Example 2 was carried out except that the fine resin particle dispersion of Production Example 4 of Example 2 was not added. (However, the coating voltage was 80 V) Comparative Example 3 The same procedure as in Example 5 was carried out except that the fine resin particle dispersion of Production Example 1 of Example 5 was not added. (However, the coating voltage was 100 V) Comparative Example 4 The same procedure as in Example 6 was carried out except that the fine resin particle dispersion of Production Example 3 of Example 6 was not added. (However, the painting voltage is 100V)

【table】

Claims (1)

[Scope of Claims] 1. (a) an aqueous dispersion of an aqueous resin that can be electrodeposited; (b) a cross-linked aqueous resin having a particle size of 0.01 to 20 μ and uniformly dispersed in the aqueous dispersion of the aqueous resin; degree is 0.01~
An electrodeposition coating composition comprising 5.05 mmol/g of internally crosslinked fine resin particles as an essential component. 2. The electrodeposition coating composition according to item 1, wherein the aqueous dispersion of the electrodepositable aqueous resin is an emulsion. 3 The aqueous resin has a first aqueous resin having an anionic group.
The electrodeposition coating composition according to item 1 or 2. 4 The aqueous resin has a cationic group.
The electrodeposition coating composition according to item 1 or 2. 5 Items 1 to 4, wherein the amount of the fine resin particles is 1 to 50% by weight of the solid content of the aqueous resin.
The electrodeposition coating composition according to any one of paragraphs.