METHOD FOR DECORATIVE ELECTROCHEMICAL FINISHING OF SILVER SURFACE Russian patent published in 2015 - IPC C25F3/02 

FIELD: chemistry.

SUBSTANCE: method includes treating with aqueous sodium thiosulphate solution with Na₂S₂O₃·5H₂O content of 790 g/l at temperature of 20±2°C using pulsed unipolar and bipolar rectangular currents with the following amplitude-time parameters: t_puls=100-500 mcs, t_{"отр."puls}=100-500 mcs, t_"з"=100-500 mcs, t_pause=100-500 mcs, amplitude current density in a positive polarity pulse i_puls=0.25-0.8 A/cm², amplitude current density in a reverse polarity pulse i_{"отр."puls}=0-0.6 A/cm², and treatment duration of 2-4 minutes, wherein the current is unipolar at I_{"отр."puls}=0.

EFFECT: forming fine, medium and large patterns on irregularly shaped surfaces, including thin-wall and thin-sheet articles.

7 dwg, 1 tbl, 6 ex