Improvements in an acidic aqueous composition for the electrowinning of nickel

摘要

Plating defects may occur during the electrodeposition of nickel using compositions containing primary and secondary brighteners. According to the invention such defects are avoided by including 0.01 to 1 g/l of a sulfonated acetylenic compound or a salt of such a compound in an aqueous acidic nickel plating bath containing 0.2 to 10 g/l of saccharin, and 20 to 500 parts per million of Zn ions. The acetylenic bond and the sulfonate radical of the sulfonated acetylenic compound are connected by a carbon chain of at least one carbon atom and not more than 6 carbon atoms. The invention relates to the composition of such a bath, to the method of bright nickel plating using such a bath and to compositions for forming the bath.