PYROPHOSPHATE-AMMONIUM ELECTROLYTE OF CONTACT SILVERING Russian patent published in 2018 - IPC C23C18/42 

FIELD: technological processes.

SUBSTANCE: invention relates to the field of applying silver coatings on copper and its alloys and can be used in the technology of electronic devices, radio engineering industry for the application of decorative coatings, for the silvering of waveguides and products of complex configuration, as the electrolyte of preliminary silvering in the technology of electroplating of silver coatings. Electrolyte for contact silvering of copper and its alloys contains, g/l: silver nitrate 2–20, potassium pyrophosphate 50–300, ammonium sulfate 25–50, sodium hydroxide 5–15 and distilled water up to 1 liter; pH of the electrolyte is 9.0–11.0.

EFFECT: invention provides high adhesion of the resulting silver coatings, stability and low toxicity of the electrolyte.

1 cl, 1 tbl