JPH03244675A - Cationic electrodeposition polymer in fine gel particle form and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a cationic electrodeposition polymer in fine gel particle form useful as a material for controlling the rheological properties of cationic electrodeposition paint by the emulsion polymerization of a radical-polymerizable unsaturated monomer with a specified emulsifying agent in the presence of a cationic, acidic colloidal silica modified with a specified silane monomer. CONSTITUTION:A radical-polymerizable unsaturated monomer is subjected to emulsion polymerization by using a cationic reactive emulsifying agent having an allyl group in the molecule and a polymerization initiator comprising a water-soluble azoamide compound in the presence of a cationic, acidic colloidal silica modified with a polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group. As the silane monomer, gamma-methacryloxypropyltrimethoxysilane is preferably used in particular. Examples of the radical-polymerizable unsaturated monomer include 2-hydroxyethyl (meth)acrylate, acrylamide, acrylonitrile, styrene, alpha-olefin, and butadiene.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a cationic electrodepositable gelling fine particle polymer and a method for producing the same, and more particularly, to a cationic electrodepositable gelling fine particle polymer and a method for producing the same. An internally crosslinked colloidal silica-containing cationic electrodepositable gelling fine particle polymer obtained by emulsion polymerization using a cationic reactive emulsifier, and polymerization carried out by using a water-soluble azoamide compound as a polymerization initiator during emulsion polymerization. The present invention relates to a method for producing a colloidal silica-containing cationic electrodepositable gelling fine particle polymer with good stability.

(Prior Art) Microparticle polymers gelled by intraparticle crosslinking reaction and methods for producing the same have been widely known. For example, polymer particles containing a crosslinking monomer containing at least two ethylenic double bonds A method of emulsion polymerizing a monomer mixture containing
No. 761); Glycidyl (meth)acrylate and (
A method in which a monomer mixture containing meth)acrylic acid, etc. is dispersed and polymerized in a non-aqueous system using a dispersion stabilizer, and at the same time, these functional groups are reacted (Japanese Patent Publication No. 57-34846
Particularly, as a method for manufacturing using an alkoxysilane monomer in an aqueous system, there is a method in which a mixture of an alkoxysilane monomer and other monomers is emulsion polymerized in an aqueous medium using a non-reactive surfactant. (Unexamined Japanese Patent Publication 1986
-181173), alkoxysilane monomer
A method for obtaining a matte electrodeposited coating film for aluminum building materials by copolymerizing (meth)acrylic acid and other monomers and then dispersing them in water (Japanese Unexamined Patent Publication No. 59-67396), containing an alkoxysilane group and a carboxyl group. An aqueous solution composition in which an acrylic polymer and colloidal silica are combined (Japanese Patent Publication No. 61-47178), an acrylic copolymer containing an alkoxysilane group and a cationic group is water-dispersed,
A method of particle crosslinking (Japanese Patent Application No. 62-54141) has been proposed.

(Problem to be Solved by the Invention) Gelled particulate polymers obtained by conventional methods are added to coating compositions to influence the rheological and physical properties, resulting in poor coating spray efficiency and coating film formation. Contributes to improvements in prevention of dripping and pattern control of metallic pigments.

On the other hand, cationic electrodeposition paints, which are widely used mainly in the automobile industry, have excellent anti-corrosion properties, but have the disadvantage that the coating film does not thicken at the edges of the object to be coated, resulting in poor edge coverage. There is a need for improvement. Therefore, in order to solve the above problems, the present inventors investigated the application of the above-mentioned gelled fine particle polymer to Kachin electrodeposition paint, but most of the conventionally known gelled fine particle polymers are non-aqueous. It is a dispersion, or even if it is an aqueous dispersion, it is an anionic or nonionic dispersion obtained by emulsion polymerization using a non-reactive surfactant, and is usually used in cationic electrodeposition coatings. Have difficulty. parable,
Even if this material is applied to cationic electrodeposition paints, it will impair the stability of the electrodeposition bath, the electrodeposition properties, the water resistance and corrosion resistance of the coating film,
This cannot be put to practical use in this field.

On the other hand, the present inventors first water-dispersed a mixture of an acrylic copolymer containing a hydrolyzable alkoxysilane group and a cationic group and cationic acidic colloidal silica, and found that the mixture was crosslinked in particles. We have proposed a characteristic colloidal silica-containing cationic electrodepositable gelatinized fine particle polymer and its manufacturing method (Japanese Patent Application No. 213661/1983). This colloidal silica-containing cationic electrodepositable gelling fine particle polymer has cationic 1t@ properties and does not impair bath stability or electrodeposition properties even when added to cationic W paints, and the baked coating film is an edge cover. They are particularly good at sex, but
The coating surface electrodeposited and baked on the horizontal portions had the disadvantage of losing its luster, which was unsatisfactory in practical terms.

(Means for Solving the Problems) The present inventors have conducted intensive research to develop a cationic tS gelling fine particle polymer useful as a rheology control agent for cationic electrodeposition paints, and as a result, we have found that cationic acidic colloidal It has been found that a cationic M-adhering gelling fine particle polymer containing colloidal silica within the particles and whose silica surface is grafted with an acrylic copolymer is extremely effective in solving the above problems. In addition, this product has cationic 1fW properties, and even when added to cationic electrodeposition coatings, it does not impair bath stability, electrodeposition properties, water resistance, or corrosion resistance of the coating, and it does not impair the stability of cationic electrodeposition coatings. The present inventors have discovered that this is extremely effective in improving finishing properties and edge coverage, and have completed the present invention.

Thus, according to the invention, in the presence of a cationic acidic colloidal silica modified with a polymerizable unsaturated vinylsilane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group,
Provided is a colloidal silica-containing cationic electrodepositable gelling fine particle polymer, which is formed by emulsion polymerizing a radically polymerizable unsaturated monomer using a cationic reactive emulsifier containing an allyl group in the molecule. .

According to the invention, also in the presence of a cationic acidic colloidal silica modified with a polymerizable unsaturated vinyl silane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group,
Cationic electrodeposition containing colloidal silica, characterized in that a water-soluble azoamide compound is used as a polymerization initiator when emulsion polymerizing a radically polymerizable unsaturated monomer using a cationic reactive emulsifier containing an allyl group in the molecule. A method for producing a gelling particulate polymer is provided.

Colloidal silica used in the present invention includes:
An aqueous dispersion having Sing as a basic unit, especially 0
．． In the present invention, colloidal silica having a cationic surface and an acidic dispersion state are particularly preferred. can be used.

Commercial products of such cationic acidic colloidal silica include, for example, "Applied CT-100,""AppliedCT-300J," and "Applied CT-400."
J (non-electrified industrial ceramic products), “Snowtex OJ
(Mass-produced chemical industrial ceramic products), “Cataroid SNJ (
Examples include Catalysts & Chemicals Industries ■Products).

The polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group used in the present invention is an extremely important component in imparting grafting active sites to the surface of cationic acidic colloidal silica. Yes, the following - Formula % Formula % In the formula, Q represents a polymerizable unsaturated group such as a γ-methacryloxypropyl group or a vinyl group, and R represents an acetoxy group or an alkoxy group having 1 to 8 carbon atoms. It is a compound represented by , .

Examples of such alkoxy groups include methoxy, ethoxy, propoxy, butoxy, imbutoxy, pentoxy, hexoxy, and the like, as well as methoxymethoxy, ethoxymethoxy, alkoxyallyloxy, ethoxyphenoxy, and the like. Preferred R is a methoxy or ethoxy group. The silane monomers are known per se or are prepared analogously to those known per se. Specific examples of such silane monomers include:
Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris(2-methoxyethoxy)silane, γ-
Examples include methacryloxypropyltrimethoxysilane, vinyltriacetate, oxysilane, and the like, and among these, γ-methacryloxypropyltrimethoxysilane is particularly preferred.

Although the mixing ratio of the cationic acidic colloidal silica and the polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group is not strictly limited, generally the solid content The ratio of the polymerizable unsaturated vinyl silane monomer containing a double bond and a hydrolyzable alkoxysilane group to 100 parts by weight of the cationic acidic colloid is preferably in the range o, oi to 10 parts by weight, more preferably 0.1 to 10 parts by weight. More preferably, the amount is in the range of 5 parts by weight.

The radically polymerizable unsaturated monomers used in the present invention are divided into the following groups.

(2) Hydroxyl group-containing monomers, such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, allyl alcohol, methalyl alcohol, etc.

■) Nitrogen-containing alkyl (meth)acrylates, such as dimethylaminoethyl (meth)acrylate.

■) Polymerizable amides, such as acrylamide, methacrylic amide, N,N-dimethylacrylic amide, N,
N-dimethylaminopropylic acid amide.

■) Polymerizable nitriles, such as acrylonitrile and methacrylonitrile.

■) Alkyl (meth)acrylates, such as methyl (meth)acrylate, ethyl (meth)acrylate, n-
Butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc.

(2) Polymerizable glycidyl compounds, such as glycidyl (meth)acrylate.

(2) Polymerizable aromatic compounds such as styrene, α-methylstyrene, vinyltoluene, t-butylstyrene, etc.

■) α-olefins, such as ethylene and propylene.

■) Vinyl compounds, such as vinyl acetate and vinyl propionate.

X) Diene compounds such as butadiene, isoprene, etc.

XI) Blocked mono- or polyisocyanate in which one incyanate group in the molecule is blocked with a radically polymerizable monohydroxy compound, monoisocyanates used in the above components include phenyl isocyanate, p-chlorophenylisocyanate, 0 -Chlorphenylisocyanate, m-chlorphenylisocyanate, 3,4-dichlorophenylisocyanate, 2
Examples include 5-dichlorophenylisocyanate, methyl isocyanate, ethyl isocyanate, n-butyl isocyanate, n-propylisocyanate, and octadecyl isocyanate. These monoisocyanates may be used alone or in combination of two or more.

Further, as polyisocyanates, aromatic polyisocyanates such as toluene diisocyanate, naphthalene diisocyanate, xylylene diisocyanate,
Hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, dibenzyl isocyanate, etc.: Aliphatic polyisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, dicyclohexyl diisocyanate, isophorone diisocyanate, etc. are exemplified. Furthermore, polymers and billet forms of these polyisocyanate compounds can also be used. The above polyisocyanates may be used alone or in combination of two or more.

Blocking agents used to block the above mono- and polyisocyanates include, for example, radically polymerizable monohydroxy compounds, specific examples of which include hydroxyalkyl esters of acrylic or methacrylic acid, tri- or tetra- Propylene glycol mono(meth)acrylate, trimethylolbroban di(meth)acrylate, pentaerythritol tri(
Examples include meth)acrylate.

The polymerizable monohydroxy compound can be used in combination with other blocking agents, and examples of blocking agents that can be used in combination include saturated or unsaturated monoalcohols having at least 6 carbon atoms, cellosolves, calpitols, and oximes. Can be mentioned.

Specific examples thereof include hexanol, nonanol, decanol, lauryl alcohol, stearyl alcohol,
Saturated monoalcohols such as 2-ethylhexanol, unsaturated monoalcohols such as oleyl alcohol and lilunyl alcohol, methyl cellosolve, ethyl cellosolve,
Examples include cellosolves such as butyl cellosolve and hexyl cellosolve, carpitols such as methyl calpitol, ethyl carpitol and butyl carpitol, oximes such as methyl ethyl ketoxime, acetone oxime, methyl isobutyl ketoxime, and cyclohexanone oxime. I can do it.

The radically polymerizable unsaturated monomers used in the present invention also include polymerizable monomers containing at least two radically polymerizable unsaturated groups in the molecule, which can be divided into the following groups.

Xl1l) Polymerizable unsaturated monocarboxylic acid esters of polyhydric alcohols, polymerizable unsaturated alcohol esters of polybasic acids, and aromatic compounds substituted with two or more vinyl groups, such as ethylene glycol di Acrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, neo Pentyl glycol diacrylate, 1,6-hexanediol diacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate,
glycerol dimethacrylate, glycerol diacrylate, glycerol aryloxy dimethacrylate,
1,1.1-trishydroxymethylethane diacrylate, 1,1.1-trishydroxymethylethane triacrylate, 1.1.1-trishydroxymethylethane dimethacrylate, 1,1.1-trishydroxymethylethane triacrylate Methacrylate, 1.1.1-trishydroxymethylpropane diacrylate, l, 1.1
- trishydroxymethylpropane triacrylate,
1.1.1-Trishydroxymethylpropane dimethacrylate, l.

Examples include 1.1-trishydroxymethylpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate, triallyl trimellitate, diallyl terephthalate, diallyl phthalate and divinylbenzene.

xm) Blocked polyisocyanate in which at least two isocyanate groups are blocked with a radically polymerizable monohydroxy compound.

The polyisocyanates used in the above block polyisocyanate include aromatic polyisocyanates such as toluene diisocyanate, naphthalene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, diphenylmethane diisocyanate, dibenzyl isocyanate, etc.; aliphatic polyisocyanates; Examples include tetramethylene diisocyanate, hexamethylene diisocyanate, dicyclohexyl diisocyanate, inphorone diisocyanate, and the like. Furthermore, polymers and billet forms of these polyisocyanate compounds can also be used. The above polyisocyanates may be used alone or in combination of two or more.

Blocking agents 1 used to block the above polyisocyanates include, for example, radical polymer monohydroxy compounds, specific examples of which include hydroxyalkyl esters of acrylic acid or methacrylic acid, tri- or tetrapropylene glycols, etc. mono(
Examples include meth)acrylate, trimethylolbroban di(meth)acrylate, and pentaerythritol tri(meth)acrylate.

The polymeric monohydroxy compound can be used in combination with other blocking agents, and examples of blocking agents that can be used in combination include saturated or unsaturated monoalcohols having at least 6 carbon atoms, cellosolves, calpitols, and oximes. Can be mentioned. Specific examples thereof include hexanol,
Saturated monoalcohols such as nonanol, decanol, lauryl alcohol, stearyl alcohol, and 2-ethylhexanol; Unsaturated monoalcohols such as nioleyl alcohol and lilunylflucol; Cellosolve B such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, and hexyl cellosolve: Examples include carpitols such as methyl carbitol, ethyl carpitol, and butyl carpitol; oximes such as methyl ethyl ketoxime, acetone oxime, methyl isobutyl ketoxime, and cyclohexanone oxime.

The radically polymerizable unsaturated monomers (I) to (chicken) are appropriately selected depending on desired properties.

Each may be used alone, or two or more types may be used in combination.

The ratio of the above radically polymerizable unsaturated monomer to the cationic acidic colloidal silica modified with a polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group is strictly limited. Generally, the solid content ratio is preferably in the range of 1 to 100 parts by weight, more preferably 5 to 70 parts by weight, of the modified cationic acidic colloidal silica per 100 parts by weight of the radically polymerizable unsaturated monomer. It is more preferable that it is in the range of .

According to the present invention, a radically polymerizable unsaturated monomer is emulsion polymerized in the presence of a cationic acidic colloidal silica modified with a polymerizable unsaturated vinylsilane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group. Typical cationic reactive emulsifiers containing an allyl group in the molecule used in this case are as follows: Formula () % Formula % In the formula, R1 has 8 carbon atoms which may have a substituent. ~22
represents a hydrocarbon group, R7 and R3 each represent an alkyl group having 1 to 3 carbon atoms, R4 represents a hydrogen atom or a methyl group, and Ae represents a monovalent anion. Reactive emulsifiers containing salts are included. The above-mentioned emulsifiers are known per se (see Japanese Patent Application Laid-Open No. 60-78947), and examples include those commercially available as Latemul-180 (trade name, manufactured by Kao Corporation). Cationic reactive emulsifiers that are gradually incorporated into the polymer are suitable, and among them, cationic reactive emulsifiers that contain an allyl group, which is a relatively low-reactivity group, are limited to those mentioned above. It can be used widely without any problems. Furthermore, the amount of the cationic reactive emulsifier containing an allyl group is not strictly limited, and can be changed depending on the type of monomer component and the physical properties desired for the type of gelled fine particle polymer produced. However, it is generally advisable to use O in an amount of 1 to 30% by weight, preferably 0.5 to 10% by weight, based on 100 parts by weight of the solid content of the gelled fine particle polymer.

In addition, as a polymerization initiator, in the following formula (II), X
represents a linear or branched alkylene group having 2 to 12 carbon atoms, or the following formula (rll), where at least one of Xl, x3 and x3 is a hydroxyl group,
Particularly suitable are water-soluble azoamide compounds of the form, where the others represent hydrogen.

These compounds are known per se (Japanese Unexamined Patent Publication No. 6
1-218618, Japanese Patent Application Laid-open No. 61-63643), for example, those commercially available as VA series (trade name, manufactured by Wako Pure Chemical Industries, Ltd.). Polymerization initiators are known in the art. Although it can be used in the amount commonly used, the optimal amount is 0.1 to 1.0 parts by weight based on 100 parts by weight of the solid content of the gelled particulate polymer.
It is within the range of 5 parts by weight.

The cationic acidic colloidal silica modified with the polymerizable unsaturated vinyl silane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group can be produced according to a known method. A polymerizable unsaturated vinyl silane monomer containing a vinyl double bond and a hydrolyzable alkoxysilane group is added to an aqueous medium containing acidic colloidal silica, and a reaction temperature of about 1 to 20
This can be carried out by continuing the reaction for a period of time.

Furthermore, the copolymerization of the radically polymerizable unsaturated monomers can be carried out by emulsion polymerization, which is a method itself for producing acrylic copolymers. For example,
The above radically polymerizable unsaturated monomer is mixed in an aqueous medium containing cationic acidic colloidal silica modified with the above polymerizable unsaturated vinyl silane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group. In the presence of a cationic reactive emulsifier containing an allyl group and a water-soluble azoamide compound polymerization initiator, the
The reaction can be carried out by continuing the reaction for about 1 to about 20 hours at a reaction temperature of about 100 DEG C., thereby producing a cationically electrodepositable gelling fine particle polymer.

The cationic electrodepositable gelling particulate polymer according to the present invention typically has an aqueous dispersion of about 10 to 40% by weight based on the total weight.
It can have a resin solids content of . The gelatinized fine particle polymer usually has a particle size of 500n11 or less, preferably 10 to
The particle size can be adjusted by adjusting the amount of cationic reactive emulsifier containing allyl groups in the molecule, polymerization containing vinyl double bonds and hydrolyzable alkoxysilane groups. This can be done by adjusting the type and amount of the polyunsaturated vinyl silane monomer and the type and amount of the cationic acidic colloidal silica, and the desired range can be easily obtained.

(Functions and Effects) When the cationic electrodepositable gelatinized fine particle polymer of the present invention is added to ordinary cationic electrodeposition paints, it does not cause problems such as agglomeration, abnormal electrodeposition, and sedimentation, and can be co-electrodeposited. The gelled fine particle polymer acts as a flow regulator during heat curing of the electrodeposited coating, and exhibits excellent cissing prevention effects and edge covering effects. Furthermore, the coating film forms a micro-separated structure, resulting in a significant improvement in the physical properties of the coating film.

(Example) Hereinafter, the present invention will be explained in more detail with reference to Examples.

"Part" and "1%" indicate parts by weight and % by weight, respectively.

Production example 1 2 equipped with a stirrer, air introduction pipe, cooling pipe, and temperature control device
222 parts of inphorone diisocyanate and 50 parts of methyl isobutyl ketone were placed in a °C flask, and the mixture was stirred and heated to 70 °C while blowing dry air into the liquid phase. 0.3 parts of dibutyltin dilaurate was added thereto, and then 116 parts of 2-hydroxyethyl acrylate was added dropwise for 1 hour, and the temperature was maintained at 7Q'C for another 1 hour after the addition was completed. Subsequently, 115 parts of methyl isobutyl ketoxime was added dropwise over 1 hour. Even after the completion of the dropwise addition, the mixture was heated and kept at 70°C. The reaction mixture was collected over time and the absorption of -NGO was confirmed by IR.
The time point at which absorption of -NGO ceased was defined as the end point of the reaction. In this way, a 90% inphorone diisocyanate/2-hydroxyethyl acrylate/methyl isobutyl ketoxime block solution was obtained. The 70% solid foam viscosity of this product (solvent composition: 10% methyl isobutyl ketone, 20% n-butyl acrylate) was DE.

Production example 2 2 equipped with a stirrer, air introduction pipe, cooling pipe, and temperature control device
A J2 flask was charged with 222 parts of isophorone diisocyanate and 50 parts of methyl isobutyl ketone, and the mixture was stirred and heated to 70°C while blowing dry air into the liquid phase.

To this was added 0.3 parts of dibutyltin dilaurate, and then 232 parts of 2-hydroxyethyl acrylate was added dropwise over 1 hour. After the completion of the dropwise addition, the temperature was maintained at 70°C and one reaction product was collected over time. The absorption of NGO was confirmed by IR, and the time point when the absorption of -NGO disappeared was defined as the end point of the reaction. In this way, a 90% inphorone diisocyanate/2-hydroxyethyl acrylate block solution was obtained.

Example 1 1580 parts of deionized water and cationic acidic colloidal silica "Applied CT-300J" were placed in a 12 flask equipped with a stirrer, a thermometer, a cooling tube, and a heating mantle.
2500 parts of Asahi Denka Kogyo product, solid content 20% and 10 parts of KBM-503 (γ-methacryloxybrobyltrimethoxysilane, manufactured by Shin-Etsu Chemical) were added and kept at 80°C for 2 hours with stirring. . After that, -1 to Latemur
360 parts of 80 (manufactured by Kao ■, 25% aqueous solution) were added, and the temperature was raised to 90° C. with stirring. To this was added 20% of an aqueous solution mixture in which 50 parts of VA-086 (manufactured by Wako Pure Chemical Industries, Ltd.), a polymerization initiator, was dissolved in 2000 parts of deionized water.

After 15 minutes, 5% of the following monomer mixture was added.

Styrene: 480 parts N-butyl acrylate: 480 parts 2-hydroxyethyl acrylate: 40 parts Then, after further stirring for 30 minutes, dropwise addition of the remaining monomer mixture and the aqueous polymerization initiator solution was started. The monomer mixture was heated to 1 weight in 3 hours.
The polymerization initiator aqueous solution was supplied every 3.5 hours, and the polymerization temperature was kept at 90°C.After the dropwise addition of the polymerization initiator aqueous solution was completed, the polymerization initiator aqueous solution was heated for 30 minutes and kept at 90°C, then cooled to room temperature, and then heated in a furnace cloth. It was filtered and taken out. Thus, solids content 22
．． 5%, pH 4.4, a viscosity of 175 cps (BM type rotational viscometer, 2 spindles), and an average particle diameter of 250 nm (measured with Coulter Nanosizer N-4).

Examples 2 to 7 In Example 1, the amount of deionized water initially charged, the type and amount of cationic acidic colloidal silica, KBM-5
Emulsion polymerization was carried out in the same manner as in Example 1, except that the amount of 03, the type of polymerization initiator, and the monomer composition were changed as shown in Table 1 to obtain a gelled fine particle polymer having the properties shown in Table 1. Ta.

*1 Cationic acidic colloidal silica (manufactured by Asahi Denka Kogyo ■, solid content 20%) *2 γ-methacryloxypropyltrimethoxysilane (manufactured by Shin-Etsu Chemical Co., Ltd.) *3 Quaternary ammonium salt-based cationic allyl group-containing Reactive emulsifier (manufactured by Kao ■, 25% aqueous solution) *4 VA-086,2,2'-azobis[2-methyl-N-(2-hydroxyethyl)-propionamide] (manufactured by Wako Tsumugi Kogyo ■) VA -080,2,2'-azobis(2-methyl-N-[1,1'-bis(hydroxymethyl)-2-hydroxyethyl]propionamide) (manufactured by Wako Tsumugi Kogyo ■) *5 BM type rotational viscosity Comparative Example 1 3,507.5 parts of deionized water and -180 parts of Latemul were placed in an IJ2 flask equipped with a stirrer, thermometer, cooling tube, and heating mantle. Add 80 parts and heat to 90℃ while stirring.
The temperature rose to . To this was added 20 percent of an aqueous mixture of 12.5 parts of VA-086, a polymerization initiator, dissolved in 500 parts of deionized water. After 15 minutes, 5 percent of the following monomer mixture was added.

Styrene: 450 parts N-butyl acrylate: 470 parts 2-hydroxyethyl acrylate: 40 parts 1.6-hexanediol diacrylate: 40 parts After further stirring for 30 minutes, dropwise addition of the remaining monomer mixture and the aqueous polymerization initiator solution was started. The monomer mixture was supplied for 3 hours, and the polymerization initiator aqueous solution was supplied for 3.5 hours, and the polymerization temperature was kept at 90 °C. After the dropwise addition of the polymerization initiator aqueous solution was completed, the mixture was heated for 30 minutes and kept at 90 °C. The mixture was cooled to room temperature, filtered using a furnace cloth, and taken out.

Thus, solids content 20.0%, pH 3.9, 90 cps
A gelled fine particle polymer having a viscosity of 73 nm and an average particle diameter of 73 nm was obtained.

Comparative Example 2 The following monomer mixture was used as a monomer mixture in the same formulation as in Comparative Example 1.

Styrene 430 parts n-butyl acrylate 440 parts 1,6-hexanediol diacrylate 40 parts 2-hydroxyethyl acrylate 40 parts KBM-
503, 50 parts Thus, solids content 21.0%, pH 3.8, 105 cp
A gelled fine particle polymer having a viscosity of s and an average particle diameter of 76 nn+ was obtained.

Application Example 1 50 parts of the gelled fine particle polymer obtained in Example 1 was added to 572 parts of a cationic electrodepositing clear emulsion (trade name, Nileclone 9450, manufactured by Kansai Paint Co., Ltd.) with a solid content of 35% consisting of a polyamide-modified epoxy resin and a completely blocked diisocyanate. Pigment paste 1 below with a solid content of 43%
Add with stirring 39.4 parts of deionized water and 588.5 parts of deionized water.
A cationic electrolyte paint was obtained by diluting the solution with

Application Examples 2 to 8 In Application Example 1, Example 2 was used as the gelling fine particle polymer.
Cation IIW paints were obtained in the same manner except that 50 parts of each of the dispersions obtained in Examples 1 to 6 and Comparative Examples 1 to 2 were used.

In the cationic T@ paint obtained in Application Examples 1 to 8, a cold-rolled dull steel plate of 0.8 x 300 (at an angle of 45 degrees), and electrodeposition was performed using it as a cathode. 1t@
Painting conditions are: electric @ paint bath temperature 30℃, pH 6.5, voltage 3
00V, and the film thickness (based on the drying film thickness) is 20 units.
Form an I@ coating film, wash the coating film with water after electrodeposition, and heat at 185°C for 2
Baking was performed for 0 minutes. The performance test results of this coated board are shown in Table 2 below, and the measurement results of the coating film melt viscosity are also shown in Table 2.

[Performance test method] (*l) Melt viscosity of coating film I! during baking @ Rolling ball viscosity measurement method (J
I 5-Z-0237+: Semi-Sur) Evaluation was made from the thermal fluid appearance of the scratch marks compared to the tono. The numerical value indicates the lowest viscosity (centipoise).

(*2) A test plate is prepared by electrocoating a steel plate with an angle of 45° at the 5-joint part under the condition that the cured film thickness of the flat part is 20 degrees, and hardening it under the specified baking conditions. Set the test plate in the Tsuruto spray device so that the edge part is vertical, and apply JIS-Z-
The corrosion resistance of the edge portion after 168 hours is evaluated by the 2371 salt spray test.

0: No rust at all ○: Slight rust occurrence ×: Significant rust occurs (*3) Smoothness of painted surface Visually evaluate the finish of the electrodeposited surface.

○: Good O: Poor △: Slightly poor (*4) Impact resistance JIS-5400-19796, 13, 3B method, 6 weight: 500 g, conducted in an atmosphere of 20°C.
The maximum height (am) that does not cause paint film damage under the conditions of the tip diameter of the center of impact (% inch) was set at 50ca+.

(*5) Chipping resistance Baking type@Painted board is further coated with thermosetting intermediate paint and top coat, and after being heated and cured, the following tests are conducted.

■Test equipment: Q-G-R Gravelometer (product of Q Panel Company) ■Stones to be sprayed: Crushed stones with a diameter of 15 to 20mm■ Capacity of stones to be sprayed: Approximately 500d■ Sprayed with air pressure crab approximately 4kg/ cm"■Temperature during test: Approximately 20℃ The test piece was attached to a test piece holding stand, and the test piece was sprayed with approximately 500 kg of crushed stone using air pressure at a rate of approximately 4 kg/cm", and the coated surface condition was determined. was evaluated. The condition of the painted surface is visually observed and evaluated using the following criteria.

(Evaluation) 0 (Good): Only a few scratches due to impact were observed in a part of the top coat, and no peeling of the electrodeposited film was observed.

■ (Slightly poor): There are scratches caused by impact on the top coat and intermediate coat, and slight peeling of the electrodeposition coat is observed.

Δ (Poor): Many scratches due to impact were observed on the top coat and intermediate coat, and considerable peeling of the electrodeposition coating was also observed.

(*6) Secondary adhesion after immersion in hot water After being immersed in water at 40°C for 20 days, JIS-5
400-19766, 15, and adhesive cellophane tape was applied to the surface of the coating, and the coated surface was evaluated after it was rapidly peeled off.

0: Good with no abnormalities △: Slight peeling of the edges of the gongs ×: Part of the gongs are peeling off (*7) Make cross-cut scratches on the coating film with a knife to reach the anti-corrosion base. This is 8 according to JIS Z 2371.
A 40-hour salt water spray test was conducted, and evaluation was made based on rust from knife scratches and the width of blisters.

○: The maximum width of n or bulge is less than one question from the cut part (
one side).

■: The maximum width of rust or blisters is 1 mm or more and less than 2 mm from the cut part (one side).

Δ: The maximum width of rust or flaking is 2III1 from the cut part
3I is less than 1m (on one side), and blisters are quite noticeable on the flat surface.

×: M or the maximum width of the bulge is 3III from the cut part
11 or higher, and blisters are observed on the entire painted surface.

(*8) Using the aqueous dispersion of the L effect application example as an electric IF paint, use a stainless steel plate as an anode, L-shaped (ratio of horizontal part to vertical part is 1/1, horizontal part is on the opposite electrode (anode) side) A zinc phosphate iron plate bent in such a way as to face each other was used as a cathode, and electrodeposition was applied to a film thickness of 20 μm. After washing the ms coated test plate with water,
Baking was carried out for 30 minutes, and the appearance of the paint film was visually observed to determine baking in the horizontal areas.

Evaluation criteria ○: Excellent smoothness.

Δ: Bumps appear partially.

×: Bumps appear on the entire surface.

Claims (1)

[Scope of Claims] 1. In the presence of cationic acidic colloidal silica modified with a polymerizable unsaturated vinyl silane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group, a radically polymerizable unsaturated monomer 1. A colloidal silica-containing cationic electrodepositable gelling fine particle polymer, which is obtained by emulsion polymerization using a cationic reactive emulsifier containing an allyl group in the molecule. 2. In the presence of cationic acidic colloidal silica modified with a polymerizable unsaturated vinyl silane monomer containing a vinylic double bond and a hydrolyzable alkoxysilane group, a radically polymerizable unsaturated monomer is converted into an allyl group in the molecule. A method for producing a colloidal silica-containing cationic electrodepositable gelling fine particle polymer, which comprises using a water-soluble azoamide compound as a polymerization initiator during emulsion polymerization using a cationic reactive emulsifier containing colloidal silica.