RU2262522C2 - Protective varnish composition and method for production of protective coating on nickel, tin and alloys thereof - Google Patents

Abstract

FIELD: protective varnish composition and method for production of anticorrosion protective coating with high resistance in harsh environment.

SUBSTANCE: claimed composition contains varnish which represents 68±2 % maleinized polybutadiene solution in diacetone and isopropyl alcohols, modified by 50-100 g/l phenol resin with addition of 25 % ammonium aqueous solution (3-6 mg/l) and isopropyl alcohol/water mixture in ratio of 1:1 up to 1 l. Composition has pH of 6.5-7.5. Method includes chemical degreasing, washing in cold flowing water, activation for 30-60 s in solution of phosphoric acid (1.5 ml/l) and auxiliary additive (10 g/l), washing in distilled water, coating of protective varnish composition by direct dipping at 15-35°C for 2-4 min, elimination of drop moisture, and drying at 140-180°C for 1 h or more.

EFFECT: composition being capable to form corrosion-resistant varnish coating on nickel, tin and alloys thereof.

2 cl, 3 ex

Description

The invention relates to varnish protective compositions and can be used as anticorrosive protection of nickel, tin and its alloys to protect products operating in various climatic conditions.

Water-borne lacquer composition for anticorrosive protection of copper alloys is known in modern technology. [USSR Author's Certificate No. 691475], consisting of g / l:

Residrol VA-133 150-160 Resin K421-02 10 Varnish PF-060 10 Triethyleneamine 19 ml / l Manganese Sulfate 0.3 Distilled water up to 1 liter

The application of this water-borne varnish composition is carried out by electrodeposition.

The closest in technical essence to the proposed composition and method for producing a protective lacquer coating for nickel, tin and its alloys are a protective lacquer composition and a method for producing a protective coating for composite waveguide devices made of aluminum alloys. [Patent No. 2196156 published January 10, 2003] based on KCH-0125 varnish, which is a 68 ± 2% solution of maleated polybutadiene in isopropyl and diacetone alcohol modified with phenolic resin with the addition of 25% aqueous fatty acid ammonia desiccant ZhK-10 and a mixture of isopropyl alcohol and water in a ratio of 1: 1 in the following ratio of components:

Varnish KCh-0125 270-300 g / l Ammonia water 25% solution 14-16 ml / l Desiccant LCD 10 12-18 g / l A mixture of isopropyl alcohol and water 1: 1 up to 1 l pH of the composition 6.5-7.0

A method of obtaining a protective varnish composition includes the following operations: etching, washing in hot running water, washing in cold running water, clarification, washing in cold running water, chemical oxidation of conductive, washing in cold running water, applying the protective varnish composition by simple immersion at a temperature of 15 ... 35 ° C for 3-6 minutes, washing in cold running water, removing droplet moisture and drying at a temperature of 125-180 ° C for at least 1 hour.

A disadvantage of the known technical solutions is the impossibility of obtaining high-quality varnish coatings for nickel, tin and its alloys.

An object of the invention is to provide a protective lacquer composition capable of forming a corrosion-resistant lacquer coating on nickel, tin and its alloys, and a method for producing such a protective coating.

The solution to the problem is achieved by the fact that the protective lacquer composition applied to nickel, tin and its alloys based on varnish KCh-0125 (STP6-1-48-95), is a 68 ± 2% solution of maleated polybutadiene in diacetone and isopropyl alcohol, modified phenolic resin with the addition of ammonia water 25% and a mixture of isopropyl alcohol and water in a ratio of 1: 1.

New in the proposed protective varnish composition is its following composition:

Varnish KCh-0125 50-100 g / l Ammonia water (25% solution) 3-6 ml / l Isopropyl alcohol + water (1: 1) up to 1 l pH of the composition 6.5-7.5

The method of obtaining a protective varnish coating on nickel, tin and its alloys includes washing in cold running water, applying a protective varnish composition by simple immersion at a temperature of 15 ... 35 ° C for 2 ... 4 minutes, removing droplet moisture, drying at a temperature 140 ... 180 ° С for at least 1.0 hour.

New features of the method of obtaining a protective varnish coating are chemical degreasing, carried out before washing in cold running water, activation for 30-60 seconds in a solution of the composition:

Phosphoric acid (GOST6552-80) - 1.5 ml / l Substance auxiliary OP-7 or OP-10 (GOST 8433-81) -polyoxyethylene alkyl phenol ethers - 10 g / l

washing in distilled water, applying a protective varnish composition.

When applied to nickel, tin and its alloys by the claimed method, a varnish film uniform in thickness, resistant to climatic factors, is formed from the proposed protective varnish composition.

Example 1

The corrosion protection of nickel-coated products was carried out with the following application method:

1. Surface preparation:

- chemical degreasing, for example, in a solution of an auxiliary substance OP-10, washing in cold running water;

2. Activation in solution, composition:

Phosphoric acid - 1.5 ml / l Substance auxiliary OP-7 or OP-10 - 10 g / l

within 30 seconds;

3. Rinsing in distilled water.

4. Application of the varnish film by simple immersion in a protective varnish composition of the following composition:

Varnish KCh-0125 - 50 g / l Ammonia water 25% - 3 ml / l A mixture of isopropyl alcohol and water 1: 1 up to 1 l pH of the composition - 7

for 2 min at a temperature of 25 ° C.

5. Rinsing in cold running water.

6. Removal of a drop of moisture.

7. Drying at a temperature of 140 ° C for 1.0 hour.

These parts were tested for exposure to low temperature - 65 ° C for 24 hours, cyclic exposure to temperatures from - 60 ° C to 85 ° C (3 cycles), exposure to tropical humidity for 21 days (relative humidity 98 ± 2% at 40 ° C) and salt fog for 7 days.

After testing, the appearance of the varnish film remained unchanged, corrosion of the base metal was not detected.

Example 2

Corrosion protection was carried out by the proposed protective varnish composition of waveguide structures with a channel section of 13 × 3 at a length of 500 mm coated with a tin-zinc alloy according to the following regime:

1. Surface preparation (example 1).

2. Activation in solution, composition:

Phosphoric acid - 1.5 ml / l

Claims (2)

1. Protective varnish composition for coatings of nickel, tin and its alloys, containing KCH-0125 varnish, which is a (68 ± 2)% solution of maleated polybutadiene modified with phenolic resin in diacetone and isopropyl alcohol, 25% aqueous ammonia and a mixture of isopropyl alcohol and water in a ratio of 1: 1 in the following ratio of components: Varnish KCh-0125 50-100 g / l Ammonia water 25% 3-6 ml / l A mixture of isopropyl alcohol and water in the ratio 1: 1 up to 1 l pH of the composition 6.5-7.5 2. A method of obtaining a protective varnish coating on nickel, tin and its alloys, including chemical degreasing, washing in cold running water, activation for 30-60 s in a solution of the composition: Phosphoric acid  1.5 ml / l Excipient OP-7 or OP-10 10 g / l washing in distilled water, applying the protective varnish composition according to claim 1 by simple immersion at 15-35 ° C for 2-4 minutes, removing droplet moisture, drying at a temperature of 140-180 ° C for at least 1 hour