SU1497275A1 - Solution for pickling the surface of polystyrene plastics prior to chemical metallization - Google Patents

Abstract

The invention relates to chemical deposition of metallic coatings, in particular, to solutions for etching plastics before metallization. The purpose of the invention is to increase the strength of adhesion of the coating to the substrate. According to the invention, the etching solution of polystyrene plastics contains, g / l: chromic anhydride 350-400, sulfuric acid (specific weight 1.84 g / cm ³ ) 380-420 and chromoxane 0.01-0.05. The introduction of the ethereal fluoroorganic compound chromoxane to the etching solution provides simultaneous efficient degreasing and etching of the plastics surface and, as a result, the adhesive strength of electroplating with the substrate reaches 920-980 g / cm, eliminating the delamination of coatings, increases by 2-3 times their corrosion resistance. 1 tab.

Description

The invention relates to chemical deposition of metallic coatings, in particular, to solutions for the etching of plastics from non-metallic metals, and can be used in sanitary, electrical, instrument-making and other national economic industries when creating products from polymeric materials with protective and decorative materials, electrical wires. 1dimi, etc .. coatings.

 the invention is an increase in the strength of the straining of the coating with the base.

The invention is illustrated by examples of the production of electroplating on polystyrene plastic products using the proposed etching solution containing, g / l: chromic anhydride 350-400, sulfuric acid (specific weight 1.84 g / cm) 380-420 and chromoxane (potassium oxoperfluoroalkane sulfanate) About 01-0 05. Specific compositions of the solutions and the achieved results are presented in the table, where for comparison, data on the etching of plastics in known solutions and when the concentration of components deviates from the optimum are also given (examples 8-16). From the above data, it follows that the addition of a surfactant chromoxane additive, which is surfactant, reduces the surface tension of the etching solution, ensuring uniform wetting of the polymer42

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Noah iverhbnostn, which leads to the leveling effect of the pickling solution. This, in turn, provides a uniform surface depth over the surface roughness. In contrast to the known fluororgian compounds used in the etching solutions of polymers (see table), chromoxane is stronger PLV due to the simultaneous presence of hydroxy and sulfoate grains. The presence of the latter in the chromoxane molecule provides all the advantages of additives that are derivatives of persulfonic acids, in particular, the increase in the hydrophilicity of the polymer surface and, consequently, its good degreasing; the presence of hydroxy groups in the additive determines uniform etching; its low molecular weight chromoxane gives it mobility, the ability to penetrate into the smallest pores of the surface and ensure its wetting. At the same time, the complete fluorinated skeleton of the guarantor molecule is the stability of a substance in an aggressive solution.

Thus, in the proposed solution, simultaneous degreasing and etching of the polygon surface is achieved. During processing, it is not difficult to erase. products of surfactant destruction which, due to decomposition under the coating, can lead to

Lead to its swelling and flaking, which leads to higher rates of corrosion 1st resistance. Due to the high efficacy of chromoxane, its relatively small amount of 0.01-0.05 g / l in solution provides increased adhesion of coatings to the substrate, which is significant from the point of view of the environmental problem of pollution (with drains) of the environment.

Claims (1)

These positive qualities of the proposed etching solution indicate its technical and economic advantages as compared with similar ones. I Formula of invention The etching solution of the surface of polystyrene plastics before chemical metallization, containing chromic anhydride, sulfuric acid and a perfluorosulfonic acid derivative, is characterized in that it contains chromoxane in the following ratio of components, g / l, to increase the strength of adhesion of the coating to the substrate : Chromic anhydride 350-400 Sulfuric acid (beats weight 1.84 g / cm) 380-420 Chromoxane 0,01-0,05