LIQUID WITH TRIVALENT CHROMIUM FOR CHEMICAL CONVERSION TREATMENT OF A BASE FROM ZINC OR ZINC ALLOY AND A CHEMICAL CONVERSION TREATMENT METHOD USING Russian patent published in 2019 - IPC C23C22/06 C23C22/34 C23C22/53 C09D5/08 B82B1/00 

FIELD: technological processes.

SUBSTANCE: invention can be used in surface treatment of aircrafts, car parts. Liquid which does not contain hexavalent chromium for chemical conversion treatment of surfaces of coating with zinc or zinc alloy contains ions of trivalent chromium, zirconium ions, nitrate ions, chain colloidal silica and water. Content of trivalent chromium ions in the treatment fluid is 2–200 mmol/l. Content of zirconium ions in treatment fluid is 1–300 mmol/l. Treatment fluid has concentration of chain colloidal silica in range of 25–600 mmol/l, concentration of nitrate ions in range of 30–400 mmol/l. Molar ratio of trivalent chromium ions to zirconium ions (trivalent chromium ions/zirconium ions) is 0.1–4, pH of treatment liquid is 2.5–5.0.

EFFECT: invention enables to obtain a liquid containing trivalent chromium for chemical conversion treatment of surfaces of zinc or zinc alloy coatings, capable of forming an environmentally friendly chemical conversion coating with high corrosion resistance, having a uniform silver-white appearance.

12 cl, 1 dwg, 9 tbl, 32 ex