JPH0347853A - Fluorinated aqueous dispersion, production of fluorinated aqueous dispersion and fluorinated electrodeposition coating composition of anionic matte type - Google Patents

Abstract

PURPOSE:To obtain a fluorinated aqueous dispersion containing a reaction product of fluorinated polycarboxylic acid resin and epoxy silane compound as a resin component, having excellent storage stability and useful for anionic electrodeposition coating composition capable of forming a matte coating film. CONSTITUTION:The aqueous dispersion consisting essentially of a reaction product of (A) a fluorinated polycarbonic acid resin, e.g. obtained by reacting an OH-containing radical polymerizable unsaturated monomer with a fluoroolefin and esterifying the reaction product with a polybasic acid anhydride and (B) an epoxysilane compound having one epoxy group, one or more hydroxysilane group and/or Si bond hydrolyzable group and e.g. obtained by dispersing (dissolving) the components A and B (preferably alicyclic in this case) into an organic solvent and reacting the component A with the component B till acid value of the component A becomes smaller by >=1 and blending the reaction product with a neutralizing agent and dispersing the blend into water and the electrodeposition coating composition containing the above-mentioned aqueous dispersion.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluorine-based aqueous dispersion, a method for producing the same, and a fluorine-based matte anionic electrodeposition coating composition containing the dispersion.

[Conventional technology and its problems]

Water-based paints are widely used because they use water as a medium and are free from concerns about the working environment and the risk of fire.

However, recently, due to the diversification of user needs, there has been a strong demand for a matte coating that gives off a calm atmosphere, replacing the metallic gloss windows.

Conventionally, α was used as a resin composition for matte anionic electrodeposition paints.
, β, β-ethylene saturated carboxylic acid resin and an epoxy compound containing a product obtained by heating a hydrogen emulsion is described in JP-A-58-213058.

However, the α, β, β-ethylene saturated polycarboxylic acid resin used in this publication is a hydroxyalkyl-containing ester or amide of α, β-ethylenically unsaturated carboxylic acid, β-ethylenically unsaturated carboxylic acid. It is a copolymer obtained by copolymerizing derivatives and alkyl esters of α,β ethylenically unsaturated carboxylic acids, and the final coating film formed using this product has weather resistance,
It had the disadvantage of poor chemical resistance. Also, α, β
As the epoxy compound to be reacted with the β-ethylene saturated polycarboxylic acid resin, a compound having at least one epoxy group per molecule is used.

However, when attempting to form a matte coating film using a monoepoxy compound having one epoxy group per molecule as the epoxy compound, the compound itself is not compatible with the polycarboxylic acid resin and has a large molecular weight. It is essential to use it. For this reason, there is a drawback that the monoepoxy compound prevents water dispersion, making it impossible to obtain an electrodeposition coating with excellent stability. In addition, the gloss of the formed coating film is also high (and there is a drawback that a coating film with excellent mechanical properties cannot be obtained.As an epoxy compound, a polyepoxy compound having at least two epoxy groups per molecule is used. The disadvantage of using this product is that the stabilization of the emulsion particles is impaired when the emulsion is heated, resulting in the formation of coarse particles and aggregates in the emulsion.Also, the deposited coating film obtained by electrodepositing this product is highly hydrophobic and contains excess It has disadvantages in that it has poor suitability for washing with water to remove the electrocoated paint that has adhered to it, and that the finished appearance of the coating film is poor.

Further, a resin composition for electrodeposition coatings comprising a fluorine-containing polymer having a carboxyl group and a hydroxyl group and an organoalkoxysilane compound is described in JP-A-64-75575. However, in this publication, the weather resistance of the electrodeposited coating film is limited in an electrodeposition resin composition containing a fluorine-containing polymer having a carboxyl group and a hydroxyl group and an amino resin as coating film forming components.

An organoalkoxysilane compound is used in place of the amino resin, which is a crosslinking agent component, in order to improve properties such as heat resistance and electrical insulation, and it is difficult to obtain a matte coating film from this composition. .

[Means for solving problems]

As a result of extensive research in order to solve the above-mentioned problems, the present inventors have discovered that an electrodeposition coating composition containing a reaction product of a fluorine-based polycarboxylic acid resin and an epoxysilane compound as an essential component is stable on storage. The present inventors have discovered that a matte coating film with excellent properties and cosmetic properties can be formed, and have completed the present invention.

The present invention is a matting fluorine-based aqueous dispersion containing a reaction product of a fluorine-based polycarboxylic acid resin and an epoxy silane compound as a resin component; An organic dispersion or an alicyclic epoxysilane compound containing an epoxy group and one or more hydroxysilane groups and/or a hydrolyzable group directly bonded to a silicon atom, dispersed or dissolved in an organic solvent. ! The acid value of the fluorine-based polycarboxylic acid resin is 1.
A method for producing a fluorine-based aqueous dispersion, which is characterized by reacting until the size of the fluorine-based polycarboxylic acid resin becomes smaller than or equal to 100%, and then dispersing it in water; After or before neutralizing the solution or organic dispersion with a neutralizing agent, one aliphatic epoxy group and one or more hydroxysilane groups and/or a hydrolyzable group directly bonded to a silicon atom per molecule. If the aliphatic epoxysilane compound containing Provided is a method for producing a fluorine-based aqueous dispersion, characterized in that the reaction is carried out until the fluorine-containing aqueous dispersion is reacted until It is something to do.

The fluorine-based polycarboxylic acid resin used as the resin component in the dispersion of the present invention includes a hydroxyl group-containing radically polymerizable unsaturated monomer, a fluoroolefin, and, if necessary, other radically polymerizable unsaturated monomers. A carboxyl group obtained by esterifying some or all of the hydroxyl groups in the polymer between a hydroxyl group-containing fluoropolymer obtained by a polymerization reaction and a polybasic acid anhydride, or a fluorine-based polymer having a carboxyl group and a hydroxyl group. Polycarboxylic acid polymers can be used.

First, the hydroxyl group-containing fluoropolymer will be described.

The above-mentioned hydroxyl group-containing radically polymerizable unsaturated monomer includes:
It has a radically polymerizable unsaturated double bond and a hydroxyl group that can be radically copolymerized with fluoroolefins, and specifically, hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, hydroxypentyl vinyl ether, etc. Hydroxyallyl ethers such as , ethylene glycol monoallyl ether, diethylene glycol monoallyl ether, and triethylene glycol monoallyl ether can be suitably used.

The fluoroolefins have the following general formula % (wherein R+, Rt, and R3 are H, F, and CI!
.

shows. R, , R, and R3 may be the same or different. ) can be used.

Specifically, for example, vinyl fluoride, vinylidene fluoride,
Examples include trifluorochloroethylene and tetrafluoroethylene. Among these, tetrafluoroethylene and trifluorochloroethylene are preferred because they provide a matte coating film with excellent durability and cosmetic properties.

Other radically polymerizable unsaturated monomers include those having unsaturated double bonds that are radically copolymerizable with the fluoroolefin, and conventionally known monomers may be used depending on the required coating performance. You can choose from. Specifically, α-olefins such as ethylene, propylene, isobutylene, butylene-1, etc.; vinyl ethers such as ethyl vinyl ether, isobutyl vinyl ether, butyl vinyl ether, cyclohexyl vinyl ether, etc.; vinyl acetate, vinyl lactate, vinyl butyrate, and Fatty acid vinyl esters such as vinyl acetate, vinyl caproate, vinyl bivaric acid and vinyl caprylate; fatty acid isopropenyl esters such as isopropenyl acetate and isopropenyl propionate.

The monomers include 3 to 80% by weight, preferably 5 to 50% by weight of a hydroxyl group-containing radically polymerizable unsaturated monomer, 20 to 80% by weight, preferably 30 to 70% by weight of fluoroolefin, and other radical polymerizable monomers. Sexually unsaturated monomer O~77% by weight
, preferably in a proportion of 10 to 65% by weight.

The copolymerization reaction is usually carried out in a water-soluble organic solvent in the presence of a polymerization initiator at a temperature of -20 to 150°C, preferably 5 to 9°C.
It is carried out at 5°C1 pressure of 0 to 30 kg/cm''.G, preferably 0 to 10 kg/cm2.G.

Examples of water-soluble organic solvents include acetone, methyl ethyl ketone, ketones such as cyclohexanone, methanol,
Ethanol, i-propertool, L-butanol, n-
Alcohols such as butanol, dimethylcarpitol,
Examples include ethers such as cellosolve and tetrahydrofuran, amides such as dimethylformamide and dimethylacetamide, and acetic acid esters such as methylcellosolve acetate.

Examples of polymerization initiators include peroxides such as di-i-propyl peroxydicarbonate, t-butyl peroxy phthylate, and benzoyl peroxide, and azo compounds such as azobis-1-butyronitrile and azobisvaleronitrile. Can be mentioned.

Next, the fluorine-based polycarboxylic acid polymer will be described.

The polymer is prepared by reacting the hydroxyl group-containing fluoropolymer with a polybasic acid anhydride to convert at least a portion of the hydroxyl groups in the polymer into 0-C-R4COOH (wherein R4 represents a divalent organic group). A polymer having an ester group represented by the following formula can be suitably used.

Specific examples of the polybasic acid anhydride include maleic anhydride, itaconic anhydride, succinic anhydride, phthalic anhydride, and 1.2-cyclohexanedicarboxylic anhydride.

The esterification reaction between the copolymer and the polybasic acid anhydride is usually carried out in the presence of the copolymer, the acid anhydride, and a catalyst for a reaction time of about 30 to 10
This is carried out continuously for about 1 to 10 hours at 0°C. As a catalyst,
Examples include zirconium naphthenate and tetrabutyl titanate.

The reaction molar ratio of copolymer and acid anhydride is approximately 110.5 to 11
It is 5. The amount of the catalyst is approximately 0.0% per 100 parts by weight of the copolymer.
01 to 1 part by weight is used.

Further, the fluorine-based polycarboxylic acid polymer using the fluoroolefin may be produced by reacting the hydroxyl group-containing radically polymerizable unsaturated monomer such as hydroxyalkyl vinyl ether and/or hydroxyallyl ether with the polybasic acid anhydride. The carboxyl group-containing radically polymerizable unsaturated monomer obtained by adding a fluoroolefin, optionally the hydroxyl group-containing radically polymerizable unsaturated monomer,
If necessary, those obtained by copolymerization with other radically polymerizable unsaturated monomers can also be used. The monomer is a carboxyl group-containing radically polymerizable unsaturated monomer 2 to
40% by weight, preferably 4-30% by weight, 20-80% by weight of fluoroolefins, preferably 30-70% by weight
, hydroxyl group-containing radically polymerizable unsaturated monomer O to 40% by weight, preferably 2 to 30% by weight, other radically polymerizable unsaturated monomers 0 to 74% by weight, preferably 10 to 64% by weight It can be blended with

In addition, as the fluorine-based polycarboxylic acid resin in the present invention, a monomer having a perfluoroalkyl group or a perfluoroalkenyl group at one end and an ethylenic double bond at the other end, an ethylenically unsaturated carbon A polymer obtained by copolymerizing an acid, a hydroxyl group-containing radically polymerizable unsaturated monomer, and another radically polymerizable unsaturated monomer can be used.

Monomers having both a perfluoroalkyl group or a perfluoroalkenyl group and an ethylenic double bond at the other end are preferably perfluoroptylethyl methacrylate, perfluorooctylethyl methacrylate, perfluoroisononylethyl Examples include methacrylate and perfluorodecylethyl methacrylate.

As the ethylenically unsaturated carboxylic acid, preferably acrylic acid, methacrylic acid, maleic acid, maleic anhydride,
Examples include fumaric acid, crotonic acid and itaconic acid.

Preferred examples of the hydroxyl group-containing radically polymerizable unsaturated monomer include 2-hydroxyethyl acrylate, hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, and hydroxypropyl methacrylate.

Other radically polymerizable unsaturated monomers are preferably methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, butyl acrylate, hexyl acrylate, octyl acrylate, lauryl acrylate, and cyclohexyl acrylate. , methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Alkyl (C+-+ll) esters of acrylic acid or methacrylic acid such as isopropyl methacrylate, butyl methacrylate, hexyl methacrylate, octyl methacrylate, lauryl methacrylate; vinyl aromatic monomers such as styrene, α-methylstyrene, vinyltoluene, etc. ;
Amide compounds of acrylic acid or methacrylic acid and derivatives thereof; examples include acrylonitrile and methachronitrile.

These monomers contain about 10 to 90% by weight, preferably 2% by weight of a monomer having a perfluoroalkyl group or a perfluoroalkenyl group at one end and an ethylenic double bond at the other end.
0-90% by weight, about 2-3 ethylenically unsaturated carboxylic acids
0% by weight, preferably 3 4 is about 4 to 20% by weight, hydroxyl group-containing radically polymerizable unsaturated monomer O to 40% by weight, preferably about 2 to 30% by weight
, and other radically polymerizable unsaturated monomers in an amount of about 0 to 88% by weight, preferably about 0 to 74% by weight.

The copolymerization reaction of this product is usually carried out in a water-soluble organic solvent in the presence of a polymerization initiator at a temperature of about 40 to 250° C., preferably about 50 to 180° C., for about 1 to 24 hours.

The same water-soluble organic solvent and polymerization initiator as mentioned above can be used.

In the present invention, when the former fluoroolefin copolymer is used as the fluorine-based polycarboxylic acid resin,
Since a structure in which a carboxylic acid is present in the side chain in a form separated from the fluorine atom bonded to the main chain is obtained, the advantage is that the reaction between the carboxylic acid and the next epoxysilane compound can be carried out easily. be. Further, since the coating film formed using this material has excellent properties such as weather resistance and chemical resistance, it is desirable to use this material.

The resin thus obtained has a carboxyl group as an essential component in the resin, but this carboxyl group is
It is a group necessary for water dispersion and a group used to react with the epoxy group in the epoxysilane compound. The content of the carboxyl group is such that the resin acid value is 20 to 2.
00, preferably in the range of 30 to 100, and the resin acid value after reaction with the epoxysilane compound is 19 to 199.
, preferably in the range of 30 to 100. If the resin acid value after reaction is less than 19, the stability of the aqueous dispersion tends to be poor, while if the nucleic acid value is greater than 199, the durability of the coating film may be poor.

Fluorine-based polycarboxylic acid resin is about 2000 to 1000
00, preferably in the range of about 5,000 to 80,000. If the molecular weight is less than about 2000, the matting effect of the coating film tends to be reduced, and the weather resistance, water resistance, etc. of the coating film may also be reduced.

On the other hand, if the molecular weight is greater than about 100,000, the melt flow properties of the paint film during baking may deteriorate, resulting in a matte film with poor smoothness, which is undesirable.

The fluorine-based polycarboxylic acid used in the aqueous dispersion of the present invention preferably has a hydroxyl group in addition to a carboxyl group. Utilizing the hydroxyl group, it is possible to carry out a crosslinking reaction with an amino resin, a blocked polyisocyanate compound, and the like. The content of the hydroxyl group is such that the hydroxyl value is usually in the range of 10 to 200, preferably about 20 to 100. Further, as the above-mentioned amino resin, formaldehyde adducts of melamine, urea, benzoguanamine, acetoguanamine, or mixtures thereof and alcohol etherified products thereof are used, and the amino resin does not need to be water-soluble. Blocked polyisocyanate is a polyisocyanate compound reacted with a blocking agent (e.g. alcohol, phenol, etc.), and the isocyanate compounds include tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, O-xylylene diisocyanate, m
-xylylene diisocyanate, P-xylylene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, 4.4'-methylene bis(cyclohexyl isocyanate), methylcyclohexane 2.4
(2,6) diisocyanate, 1,3-(isocyanatomethyl)cyclohexane, isophorone diisocyanate, trimethylhexamethylene diisocyanate, and the like.

The above-mentioned amino resin and block polyisocyanate may be used alone or in combination. The amount used is 50% by weight or less in terms of resin solid content.

The epoxysilane compound used to react with the fluorine-based polycarboxylic acid resin has one epoxy group and one or more hydroxysilane groups and/or a hydrolyzable group directly bonded to a silicon atom per molecule. It has the following.

The hydrolyzable group directly bonded to the silicon atom is a residue that is hydrolyzed by water or moisture to produce a hydroxysilane group, and includes, for example, a hydrogen atom; a C1-5 alkoxyl group; a phenoxy group, a tolyl group, and a tolyl group. Aryloxy groups such as oxy group, varamethoxyphenoxy group, varanitrophenoxy group, benzyloxy group; Acyloxyl group such as acetoxy group, propionyloxy group, butanoyloxy group, benzoyloxy group, phenylacetoxy group, formyloxy group; Examples of aliphatic epoxysilane compounds represented by the following formula include residues represented by CH3. Among these, alkoxyl groups, acyloxyl groups, and the like are preferred because they are easily hydrolyzed to produce hydroxysilane. Preferred epoxylan compounds have the general formula (I
) 7 CR2H5 CH3 CH3 9 0 etc.; alicyclic ring represented by general formula (II) 7 7 (wherein, R7, R11, R9 have the same meanings as above; n shows the same integer as above); The epoxysilane compound and the polysilane compound (e.g., tetramethoxysilane, tetrapropoxysilane,
Aliphatic or Alicyclic epoxy polysilane compound; aliphatic epoxy group-containing polymerizable unsaturated monomer (
For example, glycidyl (meth)acrylate, allyl glycidyl ether) or alicyclic epoxy group-containing polymerizable unsaturated monomers (for example, 3,4-epoxycyclohexylmethyl (meth)acrylate, etc.), directly bonded to hydroxysilane groups and silicon atoms. Polymerizable unsaturated monomers with hydrolyzable groups (e.g. vinyltris (β-methoxyethoxy)
Silane, vinyltriethoxysilane, vinyltrimethoxysilane, r-(meth)acryloxypropyltrimethoxysilane, 2-styrylethyltrimethoxysilane, r
-(meth)acryloxypropyltrimethoxysilanol, etc.) as an essential monomer component. Among these, it is preferable to use epoxysilane compounds represented by general formulas (1) and (If), which have excellent stability in aqueous dispersions and form matte coatings with excellent cosmetic properties in small amounts. be.

The above-mentioned epoxysilane compounds can be used alone or in combination of two or more.

Epoxysilane compound is fluorine-based polycarboxylic acid resin 1
It can be blended in a proportion of about 0.1 to 20 parts by weight, preferably about 0.5 to 10 parts by weight per 00 parts by weight. If the amount is less than about 0.1 parts by weight, a sufficient matte coating film cannot be obtained, while if the amount is more than about 20 parts by weight, the stability of the aqueous dispersion may deteriorate, so it is preferable. do not have.

The aqueous dispersion of the present invention is prepared by heating an organic solution or an organic dispersion in which the fluorine-based polycarboxylic acid resin and the epoxysilane compound are dissolved or dispersed in the organic solvent, so that the acid value of the fluorine-based polycarboxylic acid resin is 1 or more. , preferably by 2 or more, and then a basic neutralizing agent is added thereto, followed by dispersion in water. In this production method, when an epoxysilane compound having an alicyclic epoxy group is used, the reaction between the carboxyl group and the epoxy 3 4 group is carried out in an acidic atmosphere, so the ring opening of the alicyclic epoxy group is carried out quickly. This has the advantage that the reaction with carboxyl groups in the resin becomes faster. The heating conditions can be selected as appropriate so that the resin acid value falls within the above range, but are usually about 40°C to reflux temperature, preferably about 60 to 150°C.
C for about 1 to 20 hours, preferably about 1 to 15 hours. As the basic neutralizing agent, conventionally known basic compounds can be used, such as ammonia, dimethylamine, trimethylamine, diethylamine, triethylamine, diisopropylamine, butylamine, monoethanolamine, jetanolamine, triethanol. Examples include amine, monoisopropanolamine, diisopropanolamine, triisopropanolamine, N-methylethanolamine, N-aminoethylethanolamine, N-methylcitanolamine, and polyglycolamine. These neutralizing agents can be used in an amount of about 0.3 to 1.2 equivalents based on the carboxyl group of the fluorine-based polycarboxylic acid resin.

In addition, the aqueous dispersion of the present invention includes the epoxysilane compound after or before neutralizing the organic solution or organic dispersion obtained by dissolving or dispersing the fluorine-based polycarbonate resin in the organic solvent with the neutralizing agent. If it is added before neutralization, the pH of the aqueous dispersion obtained by dispersing it in water after neutralization is raised to higher than 7.0, and the aqueous dispersion is heated to carry out the reaction. can. The reaction is carried out until the acid value of the fluorine-based polycarboxylic acid resin decreases by 1 or more, preferably 2 or more. The acid value can be measured after dissolving the aqueous dispersion in an organic solvent. The heating conditions can be selected as appropriate so that the resin acid value falls within the above range, but
Usually about 40°C to reflux temperature, preferably about 40 to 80°
This can be carried out by continuing the treatment at C for about 1 to 24 hours. Generally, when a fluoroolefin copolymer is used as a fluorine-based polycarboxylic acid resin, the glass transition temperature of the copolymer is low. The stability of the aqueous dispersion may be impaired due to the fusion of the particles, and coarse particles or aggregates may be formed in the aqueous dispersion. When this compound is used, the ring opening of the aliphatic epoxy group in a basic atmosphere in the above reaction system is facilitated, and the reaction with the carboxyl group in the resin is accelerated, and the reaction temperature at 80°C
There is an advantage that the reaction can be carried out at relatively low temperatures such as:

The aqueous dispersion of the present invention may contain coloring pigments, extender pigments, coating surface conditioners, etc., if necessary.

The aqueous dispersions of the present invention can typically have resin solids content ranging from about 3 to 60% by weight, preferably from about 7 to 45% by weight.

The aqueous dispersion of the present invention can be used alone or in combination with other water-based paints as a matting agent.

As other water-based paints, conventionally known ones made by blending a base resin such as an acrylic resin or a fluorine resin with a crosslinking agent such as a melamine resin or a polyisocyanate compound can be used without particular limitation. . When used in combination, usually water-based paint resin solids content 1
The solid content of the resin in the aqueous dispersion is 10 parts by weight or more, preferably 20 parts by weight or more, based on 00 parts by weight.

The aqueous dispersion of the present invention can be used, for example, by dipping coating, roller coating,
It can be applied by means such as brush painting, flow painting, spray painting, and electrodeposition painting. Paint film thickness is usually about 5μm to 100μm
m, preferably in the range of about 10 μm to 80 μm. Although the baking time varies depending on the type of paint, it is generally considered that baking at room temperature to 250°C for about 24 hours to 10 minutes is sufficient.

Next, the application of the aqueous dispersion of the present invention to electrodeposition coating will be explained.

As the electrodeposition coating method and the apparatus used therein, any known method and apparatus conventionally used in anodic electrodeposition coating can be used. Electrodeposition coating conditions that can be used are generally bath temperature of 20 to 30°C, voltage of 100 to
400V (preferably 100-300VL energizing time 30
Electrodeposition is preferably performed in seconds to 10 minutes. A dry coating thickness of about 2 to 50 μm, preferably about 5 to 30 μm, is considered sufficient.

The objects to be coated by electrodeposition include conductive materials such as iron, steel, copper, aluminum, plated steel plates with zinc, tin, chromium, aluminum, etc. plated on the surface of the steel, and chromic acid coated on the surface of the steel. , metal materials that have been chemically or electrolytically treated with phosphoric acid or the like. Among them, various shapes of aluminum subjected to anodizing treatment (
For example, it is a plate-shaped, rod-shaped, enamel-shaped article, etc.

After the electrodeposition coating film formed on the object to be coated is lifted out of the electrodeposition bath, excess paint deposited on the electrodeposition coating film is removed by water, Ultrafiltration filtrate, or reverse osmosis. Washing with water that has permeated through the method, usually about 150 to 22
0°C1 preferably about 160-200"C and about 10~
Baking is carried out for 60 minutes, preferably about 20-40 minutes.

[Action and effect of invention]

As described above, the resin component of the aqueous dispersion of the present invention includes a carboxyl group obtained by reacting a fluorine-based polycarboxylic acid resin and an epoxysilane compound, and a hydroxyl group directly bonded to a hydroxysilane group and/or a silicon atom. It is a fluororesin with degradable groups. The epoxy group in the epoxy compound chemically bonds with the carboxyl group in the fluorine-based polycarboxylic acid resin to easily introduce a hydroxysilane group and/or a hydrodispersible group directly bonded to a silicon atom into the resin. It is something that can be done. In addition, regarding hydroxysilane groups and hydrolyzable groups directly bonded to silicon atoms, if they have hydrolyzable groups directly bonded to silicon atoms during water dispersion, they are hydrolyzed to become hydroxysilane groups, and then A condensation reaction between hydroxysilane groups or a condensation reaction between a hydroxysilane group and a hydrolyzable group directly bonded to a silicon atom is carried out. As a result of the condensation reaction, the interior of the particles of the water-dispersed product becomes a gel structure, and the surface of the particles has many hydrophilic hydroxysilane groups, forming fine and stable water-dispersed particles, resulting in excellent storage stability. Moreover, the fluidity of the paint film of this product deteriorates due to the reaction between the hydroxysilane groups on the particle surface, resulting in a fine matte coating. Usually, the coating film obtained by electrocoating a paint using fluorine-based polycarboxylic acid resin is highly hydrophobic, so when the excess electrocoating paint is washed with water, the water will spread onto the surface of the coating film. The coating film obtained by electrocoating the fluorine-based aqueous dispersion of the present invention is It is highly hydrophilic and excess electrocoating paint can be removed with water, etc., making it possible to obtain a matte coating film with excellent suitability for washing with water and an excellent finish. In addition, when baking the electrodeposited coating, polysiloxane bonds are generated by the reaction between hydroxysilane groups on the particle surface, resulting in improved weather resistance and
A matte coating film with excellent chemical and mechanical properties can be formed.

〔Example〕

The present invention will be explained in more detail. "Parts" and "%" in the examples are based on weight.

Polycarboxylic acid resin I production example: 106 parts of hydroxybutyl vinyl ether, 60 parts of diglyme, 180 parts of 1so-propatol, and 1 ml of N-dimethylbenzylamine were charged into an autoclave (pressure resistance 50 kg/cm"), and the space was replaced with nitrogen. After that, 116 parts of chlorotrifluoroethylene was added,
Heated to 65°C.

Next, diglyme/l5O-propatol (1/1 by weight) in which 2.5 parts of azobisisobutyronitrile was dissolved
40 parts of the mixture were added to start polymerization. The temperature was maintained for 20 hours with stirring. 475 parts of an organic solvent solution of a hydroxyl group-containing resin having a solid content of 42% was obtained.

The solvent was removed under reduced pressure while heating the solution to 60-80°C, and then 109 parts of 1.2
-Cyclohexanedicarboxylic anhydride and 100 μ2 of zirconium naphthenate were added and heated to react for 5 hours.

Further, the obtained reaction product was cooled to room temperature, and then butyl cellosolve was added thereto to obtain an organic solvent solution of polycarboxylic acid resin I with a solid content of 50%. The hydroxyl value and acid value of the resin are JIS
When measured by the method described in K 0070, they were 25 and 100, respectively.

1 2 Moreover, the number average molecular weight (measured by gel permeation chromatography) of the resin was 30,000.

Example of manufacturing polycarboxylic acid resin H. Pour 100 parts of isopropyl alcohol into a reaction vessel.8
15 parts of styrene, 20.2 parts of methyl methacrylate, 42 parts of 2-perfluorooctylethyl methacrylate, 10 parts of 2-hydroxyethyl acrylate, 12.8 parts of acrylic acid, and azobisisobutyrochloride were placed in a container kept at 0°C. A mixture of 1.0 part of nitrile was added dropwise over 3 hours,
Further, the same temperature was maintained for 3 hours to obtain an organic solvent solution of polycarboxylic acid resin H having a solid content of 50%. The resin had a number average molecular weight of 30,000, a hydroxyl value of 50, and an acid value of 100.

Production example of polycarboxylic acid resin ■Pour 100 parts of isopropyl alcohol into a reaction vessel.8
15 parts of styrene, 30 parts of methyl methacrylate, n-butyl acrylate) a 2.2 into a container kept at 0°C.
10 parts of 2-hydroxyethyl acrylate, 12.8 parts of acrylic acid, and 1 part of azobisisobutyronitrile.
0 parts of the mixture was added dropwise over 3 hours, and the mixture was further kept at the same temperature for 3 hours to form a polycarboxylic acid resin with a solid content of 50%.
A solvent solution was obtained.

The resin had a number average molecular weight of 30,000, a hydroxyl value of 50, and an acid value of 100.

Example 1 50 parts of polycarboxylic acid resin ■ 200 parts of an organic solvent solution, 42 parts of Melan 620 (manufactured by Hitachi Chemical ■, melamine resin, solid content 70%) and triethylamine (carboxyl group of polycarboxylic acid resin) 0.8 equivalent) was added and mixed uniformly. Next, 1096 parts of deionized water was added to the mixture while stirring, and the solid content was 10%.
% aqueous dispersion was obtained.

The aqueous dispersion was heated at a temperature of 40° C. for 12 hours while stirring to obtain an aqueous dispersion of Example 1.

Examples 2 to 11 Aqueous dispersions were produced in the same manner as in Example 1 using the formulations listed in Table 1, and then heated under the conditions listed in Table 1 to obtain aqueous dispersions of Examples 2 to 11. I got it.

Comparative Examples 1 to 6 After producing aqueous dispersions with the formulations shown in Table 1, they were heated under the conditions shown in Table 1 to obtain aqueous dispersions of Comparative Examples 1 to 6.

Compounds b to e in Table 1 are as follows.

Compound b: CHz-CH-CHz-0-CI6-5
i (CI(3) (OC2H5) 2ゝ.' Compound d: Methyltrimethoxysilane Compound e: Polyethylene glycol diglycidyl ether Sample m Alumite treatment was carried out using the aqueous dispersions of the above Examples and Comparative Examples as an electrodeposition paint bath. 6063S aluminum alloy plate (anodized film thickness 10μm) coated object (anode)
and the stainless steel plate (cathode), the dry film thickness is 10 μm.
A voltage was applied such that the voltage was applied for 3 minutes to form a coating film of electrodeposition paint on the object to be coated. Next, the coated article was lifted out of the bath, and any excess electrocoating paint that had adhered during lifting was washed away with deionized water, and then baked at 180''C for 30 minutes to obtain a cured coating.

6 of No. The test was conducted in a closed state. The evaluation is as follows.

A: There are no sediments or aggregates.

B: There are some sediments and aggregates.

C: There are sediments and aggregates.

D: There are many sediments and aggregates.

Sato Sotodara The smoothness and bumps on the surface of the coating film were visually observed.

The evaluation is as follows.

A: Excellent smoothness.

B: Slightly poor smoothness.

C: Smoothness is poor and bumps occur.

D: Smoothness is extremely poor and spots occur.

* Poor suitability for washing with water. (Defects such as stains and stripes remain on the paint film after washing with water.) Satoshi and plate gloss: 60° specular reflectance (unit: 2 %) was measured.

Goban adhesion: Make 100 1 mm square creases in the coating film with a cutter knife, and cut 100 creases with cellophane adhesive tape.
A peel test was conducted to determine the number of remaining folds.

After being immersed in an aqueous solution of sodium hydroxide having alkali resistance of 10% by weight for 72 hours, the appearance of the coating film was visually observed to determine the presence or absence of blistering.

A: There is no abnormality.

B: Some blistering occurs.

C blister occurs.

D: Significant blistering occurs.

The appearance of the coating film after being left in an aqueous sulfuric acid solution with acid resistance = 10% by weight for 72 hours was visually observed to determine the presence or absence of blistering. Evaluation was performed using the same criteria as for alkali resistance.

Weather resistance: Accelerated weather resistance test was conducted for 480 hours using a Weatherometer (manufactured by Suga Test Instruments Co., Ltd., Ducycle, 60 minutes of irradiation/60 minutes of darkness, black panel temperature of 63°C), and the gloss retention rate (unit: %) and appearance were measured. The appearance was visually observed in comparison with the coating film before the test.

A: There is no abnormality.

B: Gloss decreases and stains occur.

C: Gloss is significantly reduced and stains and whitening occur.

7 8 Example 12 To 200 parts of polycarboxylic acid resin solution, triethylamine (0.8 equivalents) and 42 parts of Melan 620 were added and mixed well, and then 1047 parts of deionized water was added to this mixture to reduce the solid content to 10. % of an acrylic aqueous dispersion was obtained. Next, 300 parts of the aqueous dispersion of Example 4 was added to 700 parts of the aqueous dispersion and mixed uniformly.
An aqueous dispersion of No. 2 was obtained.

Comparative Example 7 The glossy acrylic aqueous dispersion used in Example 12 was used as the aqueous dispersion of Comparative Example 7.

The storage stability and coating film performance of the aqueous dispersions of Example 12 and Comparative Example 7 are shown in Table 2.

Table 2 Storage stability, coating film appearance, and coating film performance were evaluated using the same evaluation methods as above.

Example 13 50 parts of polycarboxylic acid resin solution I 200 parts of organic solvent solution
35 parts of the compound were added thereto, mixed uniformly, and heated at 60°C for 6 hours while stirring. Next, this material was cooled to 20°C, and then 42 parts of Melan 620 and triethylamine (0,
8 equivalents) and mixed until uniform.

Subsequently, 1096 parts of deionized water was added to this to obtain an aqueous dispersion of Example 13 having a solid content of 10%.

Examples 14 to 20 Aqueous dispersions of Examples 14 to 20 were obtained in the same manner as in Example 13 using the formulations and heating conditions shown in Table 3.

Comparative Examples 8 to 11 Aqueous dispersions of Comparative Examples 8 to 11 were obtained in the same manner as in Example 13 using the formulations and heating conditions shown in Table 3.

Table 3 shows the storage stability, coating film appearance, and coating film performance of the dispersions of Examples 13 to 20 and Comparative Examples 8 to 11. Storage stability, coating film appearance, and coating film performance were evaluated in the same manner as above.

2 Example 21 The paint obtained in Example 4 was coated on a zinc phosphate treated steel plate with a dry film thickness of 1
Coat with a bar coater to a thickness of 5 μm, and coat at room temperature for 20 minutes.
After being left for a minute, it was baked at 180°C for 30 minutes. The coating film has appearance A, gloss 30, grain adhesion 100, alkali resistance A, acid resistance A, weather resistance (appearance A5 gloss retention rate 100)
) was in good condition.

4

Claims (1)

[Claims] 1. A mattable fluorine-based aqueous dispersion containing a reaction product of a fluorine-based polycarboxylic acid resin and an epoxysilane compound as a resin component. 2. Fluorine-based polycarboxylic acid resin and alicyclic epoxy containing one alicyclic epoxy group and one or more hydroxysilane groups and/or hydrolyzable groups directly bonded to a silicon atom per molecule After reacting an organic dispersion or organic solution obtained by dispersing or dissolving a silane compound in an organic solvent until the acid value of the fluorine-based polycarboxylic acid resin is reduced by 1 or more, a neutralizing agent is added and the mixture is dispersed in water. A method for producing a fluorine-based aqueous dispersion characterized by: 3. After or before neutralizing an organic solution or organic dispersion obtained by dissolving or dispersing a fluorine-based polycarboxylic acid resin in an organic solvent with a neutralizing agent, one aliphatic epoxy group and one aliphatic epoxy group per molecule are added. If an aliphatic epoxysilane compound containing two or more hydroxysilane groups and/or a hydrolyzable group directly bonded to a silicon atom is added before neutralization, it is dispersed in water after neutralization. A method for producing a fluorine-based aqueous dispersion, which comprises heating the obtained aqueous dispersion and causing the reaction to occur until the acid value of the fluorine-based polycarboxylic acid resin decreases by 1 or more. 4. A fluorine-based matte anionic electrodeposition coating composition containing the fluorine-based aqueous dispersion according to claim 1.