JPS63291966A - Fluororesin-containing electrodeposition coating - Google Patents

Abstract

PURPOSE:To provide the titled coating of low coefficient of friction, capable of easily giving uniform coating film thickness, containing a copolymer from a (meth)acrylic fluoroalkyl ester and other acrylic monomer component(s). CONSTITUTION:The objective coating containing a copolymer from (A) 10-80wt.% of a (meth)acrylic fluoroalkyl ester, (B) 5-30wt.% of (meth)acrylic acid or derivative having its free carboxyl group, (C) 0-30wt.% of a (meth) acrylic hydroxyalkyl ester (derivative), ad (D) 0-30wt.% of styrene or (meth) acrylic alkyl ester.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a fluorine-containing electrodeposition material, and more specifically,
A fluororesin-containing electrodeposition coating that has low friction and can easily form a uniform film thickness.

Conventional technology! Rice's heavy-duty paints include acrylic-melamine, alkyd-melamine, epoxy-melamine, and acrylic-melamine.
Thermosetting resins such as urethane-based, epoxy-urethane-based, and unsaturated polyester are used. Polybutanoene, epoxy-urethane, and the like are frequently used as undercoats for automobiles, and are now an essential process. In particular, acrylic-melamine systems have excellent appearance and film performance, so they can be used as a topcoat or as a one-foot one! Already used in various fields as a coating material'x
JT].

However, for materials such as iron that are prone to rust, one-cord electrodeposition paints are disadvantageous in terms of corrosion resistance. The reason is below
The major drawback is that rust prevention cannot be achieved by applying multiple coats during the painting process. However, corrosion resistance has improved in recent years due to electroplating such as zinc plating, nickel plating, light chrome plating, and chemical conversion coatings such as zinc phosphate treatment. Even the level of the problem has been improved by the book.

On the other hand, coatings with good corrosion resistance are required for substrates with poor corrosion resistance, such as iron, and fluorine paints, silicone paints, and the like have recently been put into practical use. However, the electrodeposition coating method using fluororesin has not yet been fully developed, and the metal lubrication surface treatment method (Japanese Patent Laid-Open No.
7-104688) and a highly weather-resistant electrodeposition coating composition (used in JP-A No. 61-977 (i5)),
In these cases, it cannot be said that the characteristics of the 71 rope 1fff are fully utilized.

Problems to be Solved by the Invention The development of fluorine paints, silicone paints, etc. has resulted in significant improvements over conventional paint technology. However, with the development of various more advanced technologies and the expansion of special applications, weight! High functionality of traps is required 6 The present invention uses fluorine a, which forms a better coating film than conventional fluororesin coatings.
The purpose is to provide an electrodeposition paint containing T-fat, and the coating film completed using the electrodeposition paint according to the present invention has the characteristics of low friction, non-adhesiveness, insulation resistance, and water-repellent properties characteristic of fluororesins. Indicates oiliness, etc.

Moreover, if the same paint is used, a coating film of uniform thickness can be easily obtained with one coating.

Means for solving the two problems The dispersant used in the fluororesin-containing electrocontaining 3W paint according to the present invention is a copolymer containing the following components (average molecular 1 is 500
0 to 80,000, preferably 20,000 to 50,000)
including.

a 10-80ffi amount% of fluorinated alkyl acrylic acid or methacrylic acid ester represented by the following general formula
, preferably 40-60% by weight, CH, = CH-CO
OR.

In the formula R,=H or CI.

R2=70roalkyl group b acrylic acid or methacrylic a or a derivative of acrylic acid or methacrylic acid with a free carboxy group 5-30% by weight, preferably 5-10% by weight, c hydro-dialkyl ester of acrylic acid or tutaacrylic acid or 1%, preferably 20-30% by weight of hydroxyfulkyl ester of acrylic acid or methacrylic acid derivative, d 0-30% of styrene or alkyl ester of acrylic acid or methacrylic acid
:X! , weight %, preferably 20 to 30 weight % Next, each component of the above a-cl will be specifically described.

a is a heptafluorinated furkyl ester of acrylic acid or methacrylic acid, and as a specific example, R in the above general formula
1 is CH3, R2 is -CH, CF, -CH, CF2C
F2H or -C1(,CF',CF)ICF, these compounds are commercially available.

b Compounds with carboxyl groups such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, hexamaric acid, crotonic acid, etc. are used, and if the blending ratio is less than 5% by weight, the dispersant itself is unlikely to become water-soluble, and if If added, the appearance of the electrodeposited film will be poor (
Become.

C Specific compounds include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)7acrylate, 3-hydroxypropyl (meth)acrylate,
Examples include hydroxybutyl (meth)7 acrylate, 4-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhedotyl (meth)7 acrylate, etc., and have excellent stability in water and electrodeposition. For crosslinking with paint, 0-30% by weight, preferably 20-30% by weight
30! Use li%.

d Specific examples include styrene, methyl(meth)7acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate-Flsec-butyl(meth)acrylate , butyl (meth)acrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate
Acrylate, n-octyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, etc. improve the adhesion between paint and metal, adjust the T of the polymer, and improve flexibility. Contained for the purpose of imparting.

The above components a=d are copolymerized according to conventional methods. As the method of copolymerization, for example, in situ polymerization or solution polymerization can be used, and the latter method is simple.

A specific synthesis method uses a polymerization initiator such as benzoin peroxide, t-butyl perbenzoate, -butyl peroxide, hydroperoxide, quinone hydroperoxide, and monobutyl peroxide.
Using 7zo compounds such as peroxide, 7zobisisobutyronitrile, 7zoisobutyric acid nitrile, etc. as solvents, water-soluble acetone, methyl ethyl ketone, methanol, ethanol, n-propatool, impropatool, n- Butanol, inbutanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mobutyl ether, etc. are used.

Polymerization is carried out at about 50 DEG to 160 DEG C. for about 2 to 24 hours until there is no remaining monomer.

The electrodeposition paint according to the present invention is a fluororesin dispersion obtained by adding 10 to 50 parts by weight of a dispersant produced by the above method and 1 to 3 parts by weight of a neutralizing agent to 100 parts by weight of a fluororesin. The solid content ratio of the water-soluble electrodeposition paint to the liquid is approximately 1:2 to 3:
91 is made by mixing so that it becomes 1. Specifically, 10 to 50 parts by weight of the above-mentioned dispersant are added to 100 parts of the fluororesin, kneaded well, and then neutralizers 1 to 3! 1 part to pH 7-10! ! do. At this time, fibrillation does not occur. Water, preferably pure water, is gradually added to this to disperse the FuJ resin in the water. The present invention can be carried out by mixing the obtained fluororesin dispersion and water-soluble electrodeposition paint with stirring so that the solid content ratio of the fluororesin and water-soluble electrodeposition paint is approximately 1 = 2 to 3:1. Electrodeposition paint is obtained.

The above neutralizing agents include ammonia and organic amines such as dimethylamine, trimethylamine, diethylamine,
Triethylamine, diisopropylamine, butylamine, monoethanolamine, jetanolamine, triethanolohelamine, monoisopropanolamine, noisopropanolamine, triisopropanolamine,
N-methylethanolamine, N-7minoethylethanolamine, N-methyljetanolamine, polyglycolamine, etc. are used. As a fluororesin!
! 17-fluorinated ethylene resin (PTFE'), tetrafluorinated ethylene, hexafluorinated propylene copolymer resin (FEP
), Tetrafluoroethylene per70roalkyl vinyl ether A 1! +If fat (PFA), tetrafluoroethylene-ethylene copolymer resin (ETFE),
Fine powders such as chlorine trifluoride ethylene resin (PCTFE) and vinylitine fluoride resin (PV clF ) are used alone or in combination of two or more.

Water-soluble electrodeposition paints include anionic and cationic electrodeposition paints, with acrylic, polyester, and polyimide paints being preferred. Shimizu Co., Ltd.) or Eleko) AM-2 (same as above) is used as a 7-ion type electrocoating paint, and Eleko) CM (same as before) is used as a cationic electrocoating paint.
It is exemplified as a paint. Further, there are types of polyester-based and polyimide-based electrodeposition paints that can be coated with a uniform film thickness by ion-exchanging water-soluble heat-resistant varnish.

Note that high heat resistance may be added to the dispersant by adding a silicone resin to modify the dispersant with silicone.

The electrodeposition paint according to the present invention is used according to a normal electrodeposition coating method. In other words, the voltage, time, temperature, etc. of energization can be determined according to conventional methods.If baking is performed after the first coating by heating above the melting point of the fluorocarbon resin, the resin will melt and form a continuous film, resulting in corrosion resistance. It can be reduced by dramatically increasing the amount of

Example A) Synthesis of dispersant 40 g of isopropyl alcohol was added to a 300-meter 4-tube flask equipped with a Zumroth reflux device, and the mixture was stirred under heating under reflux on a water bath. 12g.

40 g of 2-hydroxyethyl 7-acrylate, 12 g of n-butyl acrylate, 28 g of 2-ethyl hemosil acrylate and 56 g of trifluoroethyl methacrylate and 12 g of 2.2.3.4.4.4-hexa-70 butyl methacrylate; After adding and mixing azobisisobutyronitrile 2B as a polymerization initiator, the above-mentioned monomer was transferred to a dropping funnel.A dropping funnel was attached to the above-mentioned 4-7 glass vessel, stirring was performed using a stirring motor, and the above monomer was added under reflux of isopropyl alcohol. The mixture was divided into two parts, and the mixture was added dropwise at 10 minute intervals. The reaction was carried out for about 5 hours at a reaction temperature of 70 to 80°C until the monomer was completely exhausted.

B) Manufacture of 1st coat paint PTFE Hui Powder SO (trade name: Lubron L-2, manufactured by Daikin Industries, Ltd.) and the dispersant of Section A 20. Add triethylamine ice along with a small amount of pure water and mix. Gradually add pure water and disperse the fluororesin for 500 m.
7 separately, 100% water-soluble heat-resistant varnish (trade name Aquanel 600, manufactured by Nippon Shokubai) and 40% ion-exchanged water.
After adding 0 g and stirring, purify by ion exchange treatment to remove miscellaneous ions. 1 Mix both to make 17, 2
When anionic electrodeposition was carried out at 150 V for 2 minutes at a bath temperature of 5° C. using 5VS304 as a cathode, an electrodeposited coating film containing a fluororesin was obtained.

Further baking at 360°C for 10 minutes in an electric furnace results in PTFE.
The electrocoated paint film formed into a continuous film.

C) Characteristics/Tests The following tests were conducted on the fluororesin coated piece obtained in Section 8 (hereinafter referred to as the subject test piece).

a) Non-adhesive test After cleaning the test piece with ethanol, apply Sekisui cello tape (width 18-ken) and measure the load when hoisting the bow at the speed of 2-wheeled/S. The following results were obtained. Ta.

Table 1 b) Friction test A 3cm square test piece was placed on the test stand so that the painted surface was exposed, and a 500g weight was placed on the 3a+m square test piece and the load was applied by moving it laterally. Measure. Note that the surface of the test piece was cleaned with ethanol after each test. The results are shown in Table 2, Table t143.

Table 2 (blank below) Table 3 μS: Static friction coefficient μ: Dynamic friction coefficient Effects of the invention Electrodeposition using the electrodeposition paint according to the present invention! ! Since the electrodeposited coating contains fine fluororesin powder, the fluorine wffW is melted and formed into a continuous film by heating and baking above the melting point of the fluorine street resin. By forming a film, the corrosion resistance of the coating film is significantly increased, and a coating film having 81 properties such as low friction properties, chemical resistance, and submerged and oil-throwing properties peculiar to fluororesin is formed. Furthermore, the coating film can be obtained with a uniform thickness in one coat.

On the other hand, since the electrodeposition paint according to the present invention does not contain a surfactant such as a water-soluble dispersant, it is easy to handle and store during running. Further, there is no appearance defect caused by the surfactant, and there is no phenomenon of deterioration of other resin components due to the surfactant during baking.

Further, in the present invention, since a fine powder of fluorocarbon resin which is easily available is used, there is no need to synthesize the fluorocarbon resin from monomers, which is economically advantageous.

Therefore, the weight 1 coating according to the present invention is suitable for the chemical industry,
It can be used in a wide range of fields, including the electronics and electrical industry, machinery industry, and food industry, as well as space exploration, ocean exploration, and general households.

Claims (2)

[Claims] (1) A fluororesin-containing electrodeposition paint characterized by containing a copolymer containing the following components. a Fluorinated alkyl esters of acrylic acid or methacrylic acid 10-80% by weight b 5-30% by weight of acrylic acid or methacrylic acid or derivatives thereof containing free carboxy groups c Hydroxy alkyl esters of acrylic acid or methacrylic acid or their Derivatives 0-30% by weight d Styrene or alkyl esters of acrylic acid or methacrylic acid 0-30% by weight (2) The following A component and B component have a solid content ratio of 1:
A fluororesin-containing electrodeposition paint characterized by containing a fluororesin in a ratio of 2 to 3:1. Component A: The following components based on 100 parts of fluororesin: a) 10 to 80% by weight of acrylic acid or methacrylic acid fluorinated alkyl ester b) 5 to 30% by weight of acrylic acid or methacrylic acid or a derivative thereof containing a free carboxy group c 0 to 30% by weight of a hydroxyalkyl ester of acrylic acid or methacrylic acid or a derivative thereof d 10 to 50 parts of fluorine containing a copolymer containing 0 to 30% by weight of styrene or an alkyl ester of acrylic acid or methacrylic acid Resin dispersion. Component B: Water-soluble electrodeposition paint.