PROTECTIVE COATING FOR MEDICAL INSTRUMENTS AND METHOD OF ITS APPLICATION Russian patent published in 2018 - IPC A61L31/00 C25D3/06 

FIELD: medicine.

SUBSTANCE: invention relates to medicine, specifically to protective coatings consisting of successively applied layers of copper – 7–10 microns thick, bronze – 3–7 microns thick and containing 55 % of copper and 45 % of tin, and the top layer is 10–15 microns thick and represents an alloy containing cobalt (93±0.5 %), chromium (5±0.5 %) and tungsten (2±0.5 %), 10–15 microns thick. Also, the application of these layers is carried out as follows: copper – from a pyrophosphate electrolyte containing CuSO₄ 0.16–0.24 mol/l, K₄P₂O₇ 1.0–1.36 mol/l, K₂C₂O₄ 0.06–0.09 mol/l, at pH 8–9, temperature 45–55 °C and current density 0.5–1 A/dm², bronze layer – from tripolyphosphate electrolyte containing Na₅P₃O₁₀ 0.4–0.5 mol/l, CuSO₄ 0.06–0.08 mol/l and SnCl₂ 0.03–0.05 mol/l, at pH 6–7, temperature 20–22 °C and current density 0.8–1.4 A/dm² and the top layer is from an electrolyte containing 49–51 % of water, 49–51 % of dimethylformamide (DMF), CrCl₃ 0.35–1.26 mol/l, Na₂WO₄ 0.01–0.15 mol/l, CoCl₂ 0.01–0.05 mol/l, saccharin 0.5–2 g/l at pH 1.1–1.9, temperature 35–45 °C and current density of 15–30 A/dm².

EFFECT: coating has high hardness and wear resistance and has high corrosion resistance.

2 cl, 1 tbl, 6 ex