Cyanide-free plating solutions for monovalent metals

摘要

A solution for use in electroplating which comprises at least one monovalent metal such as copper, silver or gold which is complexed by a thiosulfate ion; and a stabilizer of an organic sulfinate compound such as, for example, one having the formula R-SO2-X wherein R is an alkyl, heterocyclic or aryl moiety and X is a monovalent cation. The stabilizer is present in an amount sufficient to stabilize the thiosulfate ion when the solution is operated at an acidic pH of less than 7. Also, the solution is substantially free of cyanide.