METHOD OF PROCESSING CHROME-PLATED TIN Russian patent published in 2003 - IPC

FIELD: plating equipment. SUBSTANCE: method involves electrolytic deposition of chromatized film and lacquering, with electrolytic deposition being carried out at current density of 20-40 A/sq.dm and temperature of electrolyte of 30-35 C, pH value of electrolyte of 2.4-2.8. Electrolyte used in the process comprises, g/l: chromium sulfate 25-100; ammonium sulfate 30-110; urea 45- 50. Method allows processing equipment service life to be increased by eliminating from process of toxic and highly corrosive chromatizing electrolyte based on Cr (VI) and replacing it with ecologically safe and less corrosive electrolyte based on salts of trivalent chromium. Method may be used for obtaining rolled products with plated coating, in particular, packaging material for canned food and food-processing industry, as well as chemical industry. EFFECT: increased corrosion-resistive properties of chrome-plated tin, improved working conditions for personnel and increased service life of equipment. 1 ex