JPS59131673A - Production of electrodeposition paint - Google Patents

Abstract

PURPOSE:To provide an electrodeposition paint giving an insulation film having excellent heat resistance, by reacting an imide epoxy resin with a glycol and a dicarboxylic acid anhydride, and dispersing the resultant water-dispersible varnish together with mica powder in water. CONSTITUTION:The objective paint is prepared by reacting (A) 100pts.wt. of an imide epoxy resin prepared by the reaction of (i) an imide ring-containing dicarboxylic acid compound of formula I (R1 is bivalent organic group) and/or (ii) an imide ring-containing dicarboxylic acid compound of formula II (R2 is bivalent organic group) with (iii) an epoxy resin with (B) 2-10pts.wt. of a glycol of formula III (R3 is bivalent organic group) and (C) 15-40pts.wt. of a dicarboxylic acid anhydride of formula IV (R4 is bivalent organic group), and dispersing the resultant water-dispersible varnish and mica powder as disperse phase in water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an electrodeposition paint using a novel water-dispersed face, and more specifically, to a method for producing an electrodeposition paint using a novel water-dispersed face. This invention relates to a method for producing electrodeposition paint using a dispersed face.

When mica powder is used alone to form an electrical layer on a conductor, the strength of the formed layer is not sufficient, so when the object to be coated is taken out of the deposition tank, the mica powder will fall off, resulting in virtually no damage to the conductor. Electrodeposition is not possible.

A method to improve this drawback is to add water-dispersed Fes as an organic insulator to mica powder, form a composite insulating layer with a co-electrical layer, and increase the strength of the film (Japanese Patent Laid-Open No. 51-89178
No. 51-114602, No. 56-921
No. 298) is shown.

In the composite insulation layer, the water-dispersed varnish acts as a binder for the mica powder and provides sufficient coating strength. Furthermore, the binder is not used to completely fill the gaps between the amounts of mica powder, but the gaps are generally left behind and impregnated with a different type of resin depending on the purpose of use to form an insulating coating.

Epoxy resins, acrylic resins, polyester resins, etc. are known as water-dispersed varnish resins used as binders. is contained in an amount of 5 to 60% (weight %, hereinafter referred to as the same sphere).

With the trend toward heat-resistant insulation, heat resistance is also required for mica electrolytic insulation bags, but none of the conventional water-dispersed type fabrics has sufficient heat resistance. In order to increase the heat resistance of the insulating layer, it is possible to reduce the proportion of water-dispersed varnish resin and increase the mica content, but increasing the mica content too much is not preferable because it reduces the film strength. The development of a heat-resistant water-dispersed varnish has been desired.

As a result of congratulatory research in view of the above-mentioned problem, 1. In a method for producing an electrodeposition paint using water as a dispersion medium and mica powder and water-dispersed resin as the dispersed phase, a method commonly used as a water-dispersed resin has been developed. An imide beam-containing dicarboxylic acid compound represented by formula (1): (wherein R is a divalent organic group) and (or) general formula (■): 1 (wherein, E', 2 are The general formula (■ ):HO-R
3-OH value) (wherein R3 is a divalent organic group), 2 to 10 parts of glycol (B) of the general formula (M: 1 1 (wherein R4 is a divalent organic group) The above problem can be solved by using a dispersion in water of a reaction product (D) obtained by reacting 15 to 40 parts of a dicarboxylic acid anhydride (0), which is a group of I discovered that.

That is, in the present invention, by using a water-dispersible varnish with good heat resistance as a water-dispersible varnish for use in electrodeposition paints, it is possible to improve the film strength and heat resistance of the mica electrodeposited insulating layer. It was effective.

The imide ring-containing dicarboxylic acid compound represented by the general formula fI) used in the present invention can be obtained by reacting trimellitic acid with an aliphatic and/or aromatic diamine J. Examples of aliphatic and aromatic diamines include hexamethylene diamine, diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenylsulfone, inphorone diamine, and diaminobenzanilide.

The imide ring-containing dicarboxylic acid compound represented by the general formula (n) can be obtained by reacting trimellitic acid with an aliphatic and/or aromatic aminocarboxylic acid,
Examples of aliphatic and aromatic aminocarboxylic acids include glycine, m-aminobenzoic acid, p-aminobenzoic acid, and the like.

Examples of the epoxy resin used in the present invention include diglycidyl ether type Epicote 828 (manufactured by Shell Chemical Company), DER552 (manufactured by Dow Chemical Company), novolac type DEN468 (manufactured by Dow Chemical Company),
Examples include alicyclic type 0Y-179 (manufactured by Ciba Geigy).

The imido-epoxy resin (A) is obtained by reacting the imide ring-containing dicarboxylic acid compound and the epoxy resin at a temperature of usually 8o to 2000a in the absence of a catalyst or in the presence of a catalyst.

Examples of the general glycols used in the present invention include ethylene glycol, propylene glycol, butanediol, and the like.

The acid anhydride represented by the general formula (M) may be any cyclic acid anhydride, such as phthalic anhydride,
Examples include tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methyltetrahydrophthalic anhydride.

In the present invention, when obtaining the reaction product (D), a solventless reaction is also possible at 0T, but it is preferable to use a solvent such as xylene or toluene. Further, metal salts such as hot-melted tin cylate and cobalt acetylacetonate can also be used.

The reaction product (D) used in the present invention is 2 to 10 parts of glycol (B) per 100 parts of imide epoxy resin (4),
It is obtained by reacting 15 to 40 parts of dicarboxylic acid anhydride (0) at 80 to 200°C in the presence of the above-mentioned solvent or in the absence of a solvent, in the presence of the above-mentioned catalyst or in the absence of a catalyst.

The water-dispersed face used in the present invention is a reaction product CD) 10
0 parts to 6-60 parts of volatile base and 0.1 parts of surfactant
50 to 2500 parts of an aqueous solution containing 5 parts of
It can be obtained by dispersing at 90°0 and further distilling off volatile substances from the aqueous solution. The reaction product CD) used here is obtained by the above reaction and preferably has an acid value of 60 to 70. The difference in mobility during electrodeposition between the water-dispersed face resin particles, which have an acid value higher than 70, and the mica powder is too large, making it impossible to form a uniform composite insulating layer. On the other hand, if the acid value is lower than 60, it may become difficult to disperse in a dispersion medium, the particle size in the dispersed state may become too large, and the moisture content of the composite insulating layer formed may become too high to be of practical use. do.

Suitable volatile bases used when dispersing the reaction product (D) in water include aqueous ammonia, trimethylamine) and triethylamine. Although there are no particular restrictions on the surfactant, anionic threads, nonionic surfactants, or a mixture thereof are advantageous from the standpoint of stability of the water-dispersed face. For example, sodium laurylbenzenesulfonate , sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium dodecyl sulfate, and polyethylene glycol laurate monoester.

The production of electrodeposition paint using the obtained water-dispersed face is carried out by adding 100 mica powder per 10 parts of solid content of the water-dispersed face of imide epoxy thread (ifJ resin), which is the reaction product (D).
This is done by mixing ~650 parts and diluting with water to give a total solids concentration of 10 to 20%.

According to the method of the present invention, when an electrodeposition coating material is produced by using the imide epoxy resin, which has high heat resistance, as a component of a water-dispersed varnish, it is possible to easily form an mN coating material that provides a composite insulating layer with high heat resistance. .

Next, the present invention will be explained in detail with reference to Examples and Comparative Examples.

Example 1 Imide ring-containing dicarboxylic acid compound formed by formula (IC!-1): 54.
69 (0,1 mol) and I) KR532136 g (o,
Imide epoxy resin 1 obtained by reacting with 4 mol)
90g, ethylene glycol 99. 609% of tetrahydrophthalic anhydride, 40g of xylene, and 0.269% of zinc octylate as a catalyst were mixed and reacted at 150" CI for 1.5 hours to obtain a reaction product with an acid value of 50. Acetone 609 was added to reduce the viscosity, and the mixture was poured into an aqueous solution 2000 Q containing 50 g of a 28% ammonia aqueous solution and lauryl sulfate soda 29, and stirred at 70°C for about 60 minutes to disperse it. Thereafter, air was blown into the dispersion to volatilize ammonia, and the pH was adjusted to 8.

The resulting water-dispersed fest and mica powder were mixed and dispersed in a weight ratio of 15:85 to produce an electrodeposition paint.

Using the electrodeposition paint, a rectangular copper wire was subjected to electrodeposition treatment at an applied voltage of 80 cm to form a composite insulating layer.

The obtained insulation In was good.

The copper rectangular wire having the composite insulating layer obtained was impregnated with an acid anhydride-curing epoxy resin (an impregnating resin consisting of Ebifuto 828190m, 150 parts of methyltetrahydrophthalic anhydride, and 1 part of benzyldimethylamine), and baking was treated. Then, an insulating film with a thickness of 100 μm was formed.

The mica content in the insulating coating, the initial dielectric breakdown voltage, and the dielectric breakdown voltage after deterioration at 260° C. for 20 days of the obtained sample were measured.

The results are shown in Table 1.

Example 2 Imide ring-containing dicarboxylic acid compound formed by formula (IC-2): 54.
89 (0,1, mol) and Ebiko) 828769
(0.2 mol) of imide epoxy resin, 5 g of propylene glycol, 60 g of hexahydrophthalic anhydride, and 60 g of xylene,
The reaction was carried out at 40°C for 2 hours to obtain a reaction product with an acid value of 55. Acetone 409 was added to the obtained reaction product to reduce the viscosity, and it was poured into a water bath solution 15009 containing 28% ammonia water bath solution 209 and LOg of sodium traurylbenzenesulfonate, and stirred at 75oO for about 50 minutes. and dispersed. Thereafter, air was blown into the dispersion to volatilize ammonia, and the pH was adjusted to 7.5.

The resulting water-dispersed Fes and mica powder are combined to reduce the solid content
They were mixed and dispersed in a ratio of 15:85 to produce an electrodeposition paint.

A rectangular copper wire having a good composite insulating layer was prepared using the electrodeposition paint in the same manner as in Example 1, and the wire was soaked with the epoxy-impregnated resin 1]d to form an insulating coating with a thickness of 100 μm.

The same measurements as in Example 1 were performed on the obtained sample.

The results are shown in Table 1.

Example 6 Imide-containing dicarboxylic acid compound 31 of the formula (IO-5): 1,
H' (0,1 mol) and DER5521029 (o,5
imide epoxy resin 13 obtained by reacting with
0, butanediol 20g, tetrahydrophthalic anhydride 76q1 xylene 409 were blended, and the mixture was heated at 150°C for 2 hours.
A reaction product with an acid value of 50 was obtained by reacting for hours. Acetone 609 was added to the obtained reaction product to lower its viscosity, and it was placed in a water bath 1i2ooo9 containing 40 g of a 28% ammonia water bath solution and 1.0 g of polyethylene glycol oleate monoester, and heated at 70°C. The mixture was stirred and dispersed for about 60 minutes. Thereafter, air was blown into the dispersion to volatilize ammonia, and the pH was adjusted to 8.

The obtained water-dispersed varnish and mica powder are heavily used as solids,
They were mixed and dispersed in a ratio of 15:85 to produce a chamber material for electrodeposition.

A rectangular copper wire having a good composite insulating layer was prepared using the electrodeposition paint in the same manner as in Example 1, and was impregnated with the epoxy resin to form an insulating coating with a thickness of 100 μm.

The same measurements as in Example 1 were performed on the obtained sample.

The results are shown in Table 1.

Example 4 Example 1 except that the solid content ratio of water-dispersed varnish and mica powder in Example 1 was changed to 30:70.
Samples were prepared in the same manner as above, and their properties were investigated.

The results are shown in Table 1.

Comparative Examples 1 to 2 Epoxy-based fests conventionally used as water-dispersed fests (water-dispersed fests made of Epifut 10 former mitetrahydrophthalic anhydride, ethylene glycol) or acrylic fests (acrylic nitrile, styrene,
All samples were prepared in the same manner as in Example 1 using a water-dispersed type of fabric consisting of ethyl acrylate and glycidyl methacrylate, and their properties were examined.

The results are shown in Table 1.

From Table 1, it can be seen that the dielectric breakdown voltage after deterioration of the sample using the water-dispersed face used in the method of the present invention is better than that of the conventional case, and the heat resistance is good.

Claims (4)

[Claims] (1) In a method for producing an electrodeposition paint using water as a dispersion medium and mica powder and a water-dispersed face resin as the dispersed phase, the water-dispersed face is expressed by the general formula (): (wherein, R is 2 an imide ring-containing dicarboxylic acid compound represented by the general formula (■): 1 (wherein R2 is a divalent organic group); General formula (■): HO-R3-OH(I[[) (wherein, R3 is a divalent organic 2 to 10 parts by weight of glycol (B), which is a group), and further anhydride (0) of lucicarboxylic acid, which is of the general formula (M: 1 1 (in the formula, R4 is a divalent organic group)) 1. A method for producing an electrocoat for electrodeposition, comprising using a dispersion in which a reaction product (D) obtained by subjecting 15 to 40 parts by weight of a reaction product (D) to water is used. (2) The reaction product Φ) has an acid value of 60 to 7.
0. A method for producing an electrodeposition coating material according to item (1) of the scope of patent application, characterized in that a coating material of 0.0 is used. (3) The dispersion contains 6 to 60 parts by weight of a volatile base and 0.1 to 5 parts by weight of a surfactant based on 100 parts of the reaction product (D).
13. The method for producing an electrodeposition paint according to claim 12, wherein the dispersion is a dispersion prepared by dispersing the electrodepositing paint in 500 to 2,500 parts by weight of a water bath liquid containing a severe tumor. (4) A method for producing an electrodeposition paint according to claim 1 (v), characterized in that a solvent is used in the reaction of the imide epoxy resin (A), the glycol (B), and the dicarboxylic anhydride (0).