Process and electrolyte for electroplating tin, lead or tin-lead alloys

摘要

A process and bath for electroplating tin, lead and tin-lead alloys. Improved brightness, solderability and broader current density ranges are achieved by the use in the baths of a soluble alkylene oxide condensate to provide a cloud point of the bath above about 90° F., a soluble bismuth compound, an aromatic aldehyde and acetaldehyde. Tin and lead are supplied to the bath as salts of alkyl or alkylol sulfonic acids with sufficient free alkyl or alkylol sulfonic acid to provide a bath pH of less than 3.