JPS6099165A - Resin composition - Google Patents

Abstract

PURPOSE:To provide a resin composition of improved chemical resistance for use as heat-resistant, inflammable, or electrical insulating coating or binder, comprising polymethylsiloxane, ethyl cellulose and hydrolyzate from silicic ester or its polymer. CONSTITUTION:The objective resin composition in the form of solution comprising (A) a product derived from hydrolysis in an alcoholic solution using acid catalyst, of silicic ester (methyl silicate, ethyl silicate, etc.) and/or its polymer, (B) polymethylsiloxane of formula, and (C) ethyl cellulose (pref. with an ethoxyl group content 45-49wt% in terms of solubility in alcohol and compatibility with other components). The amounts are as follows: the component (A): 100pts.wt. on an SiO2 solid basis the component (B): 600-1,500pts.wt. the component (C): 10-50pts.wt. For preparing the above composition, each component is used in the form of 5-60wt% (on a solid basis) alcoholic solution.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resin composition for heat-resistant, nonflammable, %1 insulation coatings and binders.

The purpose of the present invention is to provide a new resin composition that has excellent film-forming properties, which further enhances the superior heat resistance and electrical insulation properties of silicone resins, improves the relatively poor chemical resistance, especially solvent resistance. The present invention was made as follows.

In the present invention, (A) a silicate ester or a polysilicate ester which is a polymer thereof, an ester of a lower aliphatic alcohol of monosilicic acid, or a polymer thereof,
Examples are methyl silicate, ethyl silicate, propyl silicate,
Butyl silicate and its polymers. These silicate esters and their polymers are generally made into hydrolyzed products (hereinafter collectively referred to as alcoholic silica sol) by reacting with water in an alcoholic solvent using an acid as a catalyst, and then used as a binder for powder or granules. ) is used as. However, when alcoholic silica sol is used as a coating agent, unless it is coated on a substrate as a very thin film (generally less than a few um), it cannot be chalked (chalked) to form a uniform film. It has the disadvantage of not being possible.

Moreover, as the polymethylsiloxane (B), Ha %-8i-0s H3 A structure with the following structure is used.

Furthermore, the ethyl silicate (C) preferably has an ethoxyl group content of 45 to 499b in terms of solubility in alcohol and compatibility with silica sol and polymethylsiloxane. Ethyl cellulose has a remarkable effect as a film-forming agent, and has the advantage of improving the viscosity of alkaline silica sol and being relatively easily dispersed by heating, leaving no colored residue (carbide). to be worshiped.

Due to such effects of ethyl cellulose, a composition of alcohol-based silica sol, polymethylsoloxa 7, and ethyl cellulose becomes extremely useful as a heat-resistant, nonflammable, gas-insulating coating agent and binder.

In the present invention, the ratio of (A), (B), and (C) can be selected from a wide range depending on the application purpose, but (A)
5i (12) Conversion a for solid content 1 Shown in white is (A
) Against 100 weights B) 600-1500
i1Ei part (C) to-503i: part is common, and these are methanol, ethanol, glopanol,
Solid content concentration 5-6 in alcohol-based solvents such as butanol
It is used after being dissolved in 095.

The present invention will be explained in more detail with reference to Examples below.
The present invention is not limited to these Examples.

Example I (1) Preparation of hydrolyzate of ethyl silicate 100 g of ethyl silicate.

165 g of ethanol and 15 g of 0.05 N hydrochloric acid aqueous solution
After stirring at room temperature for 5 hours, it was heated for 2 hours to form an alcohol-based silica sol (Si (% hlO)).
- Got it.

(2) Preparation of paint Add 400 g of the above alcohol-based silica sol and 5 g of ethyl cellulose and dissolve completely, then add to this isopropanol solution of polymethylsiloxane (concentration 509 hours).
600 g was added to obtain a homogeneous paint solution.

This pigment solution can be applied as it is as a coating agent for plastics, glass, ceramics, metals, etc. Coating methods include dipping, soufflé,
Brush coating, spin coating, and other methods are effective, and the coating dries to the touch at 25°C for 1 hour after coating. Even if you leave it at room temperature, it's still good! Although the reaction progresses, it is heated at 140°C for 2 hours + 200°C.
It can also be cured by heating for 1 hour at °C.

(3) Example of use as a coating and binder (a) The above coating material was dip-coated onto mild steel, left at room temperature for 1 day, and then heated at 120° C. for 3 hours to obtain a transparent coating film with a film thickness of IQu+n.

As a result of the Gopan eye peeling test, this film was rated at 100/1.
It exhibited adhesion of 'OO, and the hardness of lead clam was 6H. Further, this coating film showed excellent chemical resistance, with no abnormalities observed even when immersed in pure water, ethanol, xylene, gasoline, or chlorofluorocarbon for 3 hours. Furthermore, this coating film was heated to 360°C.
After heating for 1 hour, no smoke was observed, and even after cooling, there were no abnormalities in adhesion, chemical resistance, etc., showing excellent heat resistance.

(bl) This coating film 1 is made of natural paper/synthetic paper (Nomex)
・If coated on a synthetic resin substrate, arc resistance is excellent [
Improved by 2 times. For example, in the case of pulcanized fiber, the arc resistance (JIS K6911) is uncoated 4().
~50 seconds, whereas with coating it becomes 180 seconds.

(C1 Also, if necessary, powders such as silica, mica, alumina, magnesia, boron nitride, etc. may be added to the above coating solution to form a slurry, and this can be used as a coating agent.

For example, a mica plate (cured at 250°C for 2 hours) made from the above paint/mica slurry of 20/80 (weight ratio) has a resistance of 10122 - 10 Ωcm at room temperature, 10 Ωcm at 200°C, and 10 Ωcm at 450°C.
It has extremely high electrical insulation properties even at high temperatures of 9 cm. This mica board does not change its texture even when immersed in xylene, trichlorene, alcohol, chlorofluorocarbons, pure water, etc.

Example 2 A paint was prepared in the same manner as in Example 1 except that butyl silicate was used in place of the hydrolysis product of ethyl silicate in Example 1. The visibility of the coating film using butyl silicate was better than that using ethyl silicate, but the electrical insulation, secondary arc resistance, and chemical resistance were similar to those using ethyl silicate. Met.

patent applicant Qi Nis B Co., Ltd. Representative: Eiji Otsunai

Claims (1)

[Claims] (5) Hydrolyzate of silicate ester and/or polysilicate ester - A resin composition comprising (131 polymethylsiloxa/(q) ethyl cellulose).