JPS61127772A - Matte electrodeposition paint composition - Google Patents

Abstract

PURPOSE:The titled composition, obtained by incorporating an alpha,beta-ethylenically unsaturated polycarboxylic acid resin with an alkoxylated methylolmelamine and a nonionic surfactant having a high HLB in a specific proportion, and capable of giving uniform beautiful films of large thickness. CONSTITUTION:A composition obtained by incorporating (A) 100pts.wt. (nonvolatile content) resin composition containing a product prepared by mixing (A) 5-95pts.wt. alpha,beta-ethylenically unsaturated polycarboxylic acid resin with (B) 95-5pts.wt. alkoxylated methylolmelamine with (C) 0.1-5pts.wt. nonionic surfactant having 8-16 HLB< e.g. glycerol ester of a fatty acid.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to a matte electrodeposition coating composition, and a paint that can form a thick matte electrodeposition coating film with an excellent appearance in one electrodeposition coating. Regarding the composition.

(Prior Art) In recent years, matte electrodeposition coating that can form a matte appearance has become widely practiced. This method uses a specific coating composition obtained by reacting an electrodeposition coating composition under special conditions without adding a matting agent from outside the system. (Refer to JP-A No. 58-84869.) However, when this coating composition is used for electrodeposition coating, a beautiful matte electrodeposition coating film appearance with low gloss is formed, but the coating thickness cannot be increased. There was a drawback that there was no

On the other hand, it is known that surfactants are added as dispersants for dispersing pigments, etc. in electrodeposition paints, and to prevent deterioration of the appearance of electrodeposition coatings due to changes in the electrodeposition coating bath over time. ing. (Refer to Japanese Patent Publication No. 57-34310) On the other hand,
As a method of increasing the thickness of the coating film, it has been proposed to add various surfactants to the aqueous organic resin bath. (Refer to Japanese Patent Application Laid-open No. 59-185800) However,
This invention merely shows that adding various surfactants to a general cationic or anionic aqueous organic resin bath is effective in increasing film thickness, but does not clearly indicate the appearance of the coating.

(Object of the Invention) The present invention aims to eliminate the drawbacks of the above-mentioned specific electrodeposition coating composition, and aims to form a matte electrodeposition coating film with a thick film and excellent surface appearance by -3 times of electrodeposition coating. The object of the present invention is to provide a matte electrodeposition coating composition that can be coated.

(Structure of the Invention) According to the research conducted by the present inventors, in order to form a thicker coating film than before using the specific matte layer@paint targeted by the present invention, it is necessary to The present invention was completed based on the knowledge that by blending a specific amount of an ionic surfactant, a thick, matte electrodeposited coating film with a beautiful appearance can be formed.

To outline the matte electrodeposition coating composition of the present invention, (a
) α, β-ethylenically unsaturated polycarboxylic acid resin (b)
(c) H
A nonionic surfactant having an LB of 8 to 16 is blended in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the nonvolatile components of the resin composition. To explain the present invention in more detail, the α, β-
Ethylenically unsaturated polycarboxylic acid resin (a) α, β-ethylenically unsaturated polycarboxylic acid 3 to 30% by weight) α,
β-ethylenically unsaturated carboxylic acid droxyalkyl-containing ester or amide or amide derivative 5 to 30% by weight, (c) α, β-ethylenically unsaturated carboxylic acid alkyl ester 30 to 80% by weight, (d) Other It is obtained by reacting a monomer composition composed of 0 to 20% by weight of copolymerizable monomers and blended so that the total amount is 100% by weight, and preferably has an acid value of 10 to 200. .

stomach.

Suitable (a) α,β-ethylenically unsaturated carboxylic acids include acrylic acid, α-chloroacrylic acid, methacrylic acid,
itaconic acid, maleic anhydride, maleic acid, fumaric acid,
Crotonic acid, citraconic acid, mesaconic acid, etc. alone or
Mixtures or functional derivatives thereof having at least one carboxyl group, such as partial esters or amides of unsaturated di- or poly-carboxylic acids.

(b) As the α,β-ethylenically unsaturated carboxylic acid droxyalkyl-containing ester or amide or amide derivative, 2- and droxyethyl acrylate, 2-
Hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, acrylamide, methacrylamide, de-methylol acrylamide, methylolmethacrylamide, alkoxymethylolamide, alkoxymethylolmethacrylamide,
Examples include diacetone acrylamide and diacetone methacrylamide.

(c) Examples of α,β-ethylenically unsaturated carboxylic acid alkyl esters include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-propyl acrylate, n-propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, and butyl acrylate. , butyl methacrylate, lauryl acrylate, lauryl methacrylate, stearyl acrylate, stearyl methacrylate, hexyl acrylate, 2-ethylhexyl methacrylate, heptyl acrylate, heptyl methacrylate, and similar esters having up to 20 carbon atoms in the alkyl group. Can be used.

(d) Other copolymerizable monomers include styrene, α
-Alkylstyrene, α-chlorostyrene, vinyltoluene, acrylonitrile, vinyl acetate, etc.

On the other hand, the alkoxylated methylol melamine used as component (b) may be one in which at least a portion of the methylol group is alkoxylated with a lower alcohol. As the lower alcohol, one or more of methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, etc. is used.

In the present invention, the composition ratio of the α,β-unsaturated polycarboxylic acid resin and the alkoxylated methylolmelamine is 5 to 9% of the α,β-ethylenically unsaturated polycarboxylic acid resin.
5 parts by weight of lucoxylated methylolmelamine can be used in a range of 95 to 5 parts by weight.

In the present invention, a resin composition containing as an active ingredient a product obtained by mixing the above-mentioned (a) component and (b) component,
By adding and blending a nonionic surfactant having a HL of 88 to 16, the thickness of the matte electrodeposition coating film is increased.

Nonionic surfactants include some fatty acid ester type surfactants of polyoxy compounds, such as glycerin esters of fatty acids, glycol esters of fatty acids, pentaerythritol esters of fatty acids, sorbitan and manitol esters of fatty acids, and polyethylene esters. Some of the oxide condensation type surfactants, such as higher fatty acids,
Some of the polyethylene oxide condensation type surfactants include higher alcohols, higher alkyl amines, higher fatty acid amides, higher alkyl mercaptans, and alkyl phenols.

Some of these nonionic surfactants are added in a proportion of 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, based on 100 parts by weight of the matte electrodeposition coating resin composition. Blend.

If the amount is less than 0.1 parts by weight, no effect of increasing the matte II coating film will be observed, while if it is more than 5 parts by weight, poor appearance and poor adhesion of the paint film due to abnormal electrodeposition will occur. This is not preferable because it causes

In the present invention, nonionic surfactants with an HLB of less than 8 are not preferred because they do not have a film-enhancing effect.

Further, the use of other surfactants such as anionic surfactants, cationic surfactants, or amphoteric surfactants is also not preferred because no film-increasing effect is observed.

The matte electrodeposition coating composition of the present invention can be produced, for example, by the following method.

In a reaction vessel equipped with a stirrer, a thermometer and a reflux condenser,
(a) α, β, β-ethylene saturated polycarboxylic acid resin,
(b) Mixing alkoxylated methylolmelamine in the presence of an organic solvent. During or after this mixing, a hydrophilic base is added while stirring, and water is further added to form an emulsion. Next, the temperature is raised to 40° C. to reflux temperature, and stirring is continued to complete the reaction. The lower the heating temperature, the longer the reaction time or room temperature standing time. The nonionic surfactant is added to the aqueous emulsion after the completion of the reaction, or added after diluting the aqueous emulsion and mixed by thorough stirring.

Examples of organic solvents include methanol, ethanol,
n-propyl alcohol, isopropyl alcohol, n
-butanol, isobutanol, 5eC-butanol,
Alcohols such as t-butanol, pentanol, etc., cellosolves such as methyl cellosolve, ethyl cellosolve, isopropyl cellosolve, butyl cellosolve, 5ec-butyl cellosolve, etc. are used.

Hydrophilic bases include ammonia, monomethylamine, dimethylamine, trimethylamine, monoethylamine,
Alkylamines such as diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, monobutylamine, dibutylamine, tributylamine etc., monoethanolamine, jetanolamine, triethanolamine, mono(2-hydroxypropyl) Amine, di(2-hydroxypropyl)amine, tri(2-hydroxypropyl)
amines, alkanolamines such as dimethylaminoethanol and diethylaminoethanol, alkylenepolyamines such as ethylenediamine, propylenediamine, diethylenetriamine and triethylenetetramine, alkyleneimines such as ethyleneimine and propyleneimine,
Examples include piperazine, morpholine, pyrazine, pyridine, and metal hydroxides such as sodium hydroxide, potassium hydroxide, and lithium hydroxide.

The hydrophilic base may be added in a molar ratio of 0.1 to 0.8 to the carboxyl group of the α,β-ethylenically unsaturated polycarboxylic acid resin.

When an acid is added to the resin composition of the matte electrodeposition paint of the present invention, the reaction time and the coating film baking time are shortened, and favorable results can be obtained. This is because the acid promotes the reaction with the α,β-ethylenically unsaturated polycarboxylic acid resin lucoxylated methylolmelamine to form a reaction product, and
It is presumed that this is because it acts as a crosslinking catalyst during heating and baking of the coating film.

Acids that can be blended into the resin composition in the present invention include organic acids and/or inorganic acids. Examples of organic acids include formic acid, acetic acid, oxalic acid, and sulfonic acid compounds, while examples of inorganic acids include sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid. In the present invention, at least one type of organic acid or inorganic acid, or a mixture of an organic acid and an inorganic acid can be used.

In the present invention, it is preferable to use a sulfonic acid compound because it exhibits particularly excellent effects. Sulfonic acid compounds include aliphatic sulfonic acids and aromatic sulfonic acids.

Examples of aliphatic sulfonic acids include alkanesulfonic acids such as methanesulfonic acid and ethanesulfonic acid; examples of aromatic sulfonic acids include m-nonylbenzenesulfonic acid, p-decylbenzenesulfonic acid, p-undecylbenzenesulfonic acid, and p-undecylbenzenesulfonic acid. - Alkylbenzenesulfonic acids such as dodecylbenzenesulfone a, p-toluenesulfonic acid, dinonylnaphthalenesulfonic acid, dinonylnaphthalenesulfonic acid, diakylnaphthalenesulfonic acid, dialkylnaphthalenesulfonic acid, dioctylnaphthalenesulfonic acid, didecylnaphthalenesulfonic acid A dialkylnaphthalene sulfonic acid or a disulfonic acid such as the like is used.

The acid may be added as desired, and may be added at the time of mixing the film-forming components or after mixing, for example, before adding the hydrophilic base. In addition, when adding an acid, it may be added separately and at the same time as a hydrophobic base, or in some cases, a salt-containing substance containing a reaction product with the base may be added. Effects can be obtained.

The reason why a hydrophobic base is used to neutralize an acid in the present invention is that an acid is normally neutralized by a base and becomes water-soluble, but when a hydrophobic base is used, it becomes hydrophobic even after being neutralized. The neutralized product is included in the resin of the paint film forming component, so it is not removed even if the paint is ion-exchanged, and therefore, even with continuous operation, fluctuations in the amount of acid in the paint are minimized. This is for the purpose of retaining.

It is appropriate that the acid or salt-containing substance is added in an amount of 10% by weight or less, preferably 5% by weight or less, particularly preferably 1.0% by weight or less, based on the coating film forming components of the resin composition.

This is necessary in order to preserve the excellent physical properties of the resulting matte coating.

The hydrophobic base is particularly preferably one that is sparingly soluble or insoluble in water. Examples include research alkyl amines or amines containing aralkyl groups.

The matte electrodeposition coating composition of the present invention has a resin solid content concentration of 3 to 3.
It can be used in a range of 50% by weight, and may be diluted with water to an appropriate concentration. At that time, ordinary colorants and other paint additives may be mixed and used.

Furthermore, the matte electrodeposition coating composition of the present invention can be mixed with an electrodeposition coating composition that forms a coating film with excellent gloss, and the gloss of the resulting coating film can be adjusted as desired.

When an object is coated with the matte electrodeposition paint prepared in this manner, a uniform, thick, and beautiful hazy matte coating can be formed regardless of the material, shape, and size of the object.

(Examples of the Invention) Examples are shown below to more specifically explain the present invention.

[Preparation of matte electrodeposition paint stock solution] In a reaction vessel equipped with a stirring device, a thermometer, and a reflux condenser, 10 parts of acrylic acid, 15 parts of 2- and droxyethyl methacrylate, 15 parts of styrene, 15 parts of octyl acrylate,
10 parts of butyl acrylate, 35 parts of methyl methacrylate
1.5 parts of azobisisobutyronitrile, 12 parts of ethylene glycol motubutyl ether, and 35 parts of isopropyl alcohol were charged and stirred for 6 hours under reflux to obtain α.

β-ethylenically unsaturated polycarboxylic acid resin solution (acid value 7
8) was prepared.

In a separately prepared reaction vessel equipped with a stirrer, a thermometer, and a reflux condenser, 100 parts of the above α,β-ethylenically unsaturated polycarboxylic acid resin solution was added. 30 parts of the solution were added and mixed by stirring. Next, 4.2 parts of triethylamine was added while stirring, and then 150 parts of deionized water was added to form an emulsion. The emulsified contents were heated to about 90° C. and stirred for about 12 hours to complete the reaction and prepare a matte electrodeposition paint stock solution.

Example 1 270 parts by weight of a matte N-adhesive paint stock solution was mixed with 720 parts by weight of deionized water, 12 parts by weight of ethylene glycol monobutyl ether and 1 part by weight of dimethylaminoethanol were added, and a nonionic surfactant (commercial product) was added. Name Noni Ball 9
5. 3.5 parts by weight of polyoxyethylene nonylphenyl ethyl HLB13) manufactured by Sanyo Chemical Co., Ltd. was added and thoroughly mixed to prepare a matte electrodeposition paint.

Examples 2 to 5 and Comparative Examples 1 to 2 The same method as in Example 1 was carried out except that the amount of nonionic surfactant added was varied as shown in Table 1. were prepared respectively.

Table 1 below: Examples 6 to 8 and Comparative Examples 3 to 5 The same method as in Example 1 was carried out except that the following types of nonionic surfactants were used. were prepared respectively.

Comparative Example 6 The same method as in Example 1 except that an anionic surfactant (trade name: Neogen R manufactured by Daiichi Kogyo Seiyaku Co., Ltd., nidodecylbenzenesulfonic acid sodium salt) was used instead of the nonionic surfactant. A matte electrodeposition paint was prepared by carrying out this process.

Application Examples In each of the paints prepared in Examples 1 to 8 and Comparative Examples 1 to 6,
An aluminum plate that has been anodized and inorganically colored is connected to the anode and a stainless steel plate to the cathode and immersed, and a voltage of 180 volts is applied between the two electrodes to give an initial current density of 1. OA/
dm for 2 minutes. After finishing the electrodeposition coating, take out the stand aluminum plate and thoroughly wash it with water.
Hot air drying was performed at ℃ for 30 minutes.

As a result, the electrodeposition coating films formed on each aluminum plate were as shown in Table 3.

However, the coating film adhesion test was based on the JISK-5400 substrate test.

Margins below (Effects of the Invention) As is clear from the above results, the matte electrodeposition coating composition of the present invention can form a thick matte electrodeposition coating film with an excellent appearance after - times of electrodeposition coating. It is something that can be formed.

Applicant Honey Kasei Co., Ltd. Procedural amendment writing method) % formula % 1. Indication of case 1981 Patent Application No. 25017
No. 7 1 So+l groan] -÷-Heri /-Line zo t I Fuhen 2, Title of the invention Matte electrodeposition coating composition 3, Relationship with the case of the person making the amendment Patent applicant 澗λ′ 煴4:8 Childhood address (residence) 3-1-33 Hiyoshi-cho, Nagata-ku, Kobe *a Name Name: Honey Kaoru Co., Ltd. 4 Date of amendment order: March 6, 1985 (shipment date)
(March 26, 1985) 5. Subject of amendment Clear text/Original text 6. Contents of amendment As shown in the appendix, submit a clearly written specification clearly typed (in black) and an application clearly stamped. .

Claims (1)

[Claims] 1, (a) α, β-ethylenically unsaturated polycarboxylic acid resin and (b) alkoxylated methylolmelamine as coating film forming components, product obtained by mixing the (a) component and (b) component (c) A nonionic surfactant having an HLB of 8 to 16 is added to the resin composition containing as an active ingredient, based on 100 parts by weight of the nonvolatile components of the resin composition.
．． A matte electrodeposition coating composition containing 1 to 5 parts by weight.