Bath and process for plating lead and lead/tin alloys
AssigneeLeaRonal, Inc.
InventorsFred I. Nobel, Barnet Ostrow, David N. Schram
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Abstract
This invention relates to the electrodeposition of tin, lead and particularly tin-lead alloys from an electroplating bath comprising a lead and/or tin alkylsulfonate, an alkylsulfonic acid in a sufficient amount to impart a pH below about 3 to the bath, and various additives to improve the brightness of the deposits, the useful current density ranges, and/or the solderability of tin-lead alloy deposits including quaternary nitrogen wetting agents containing a fatty acid radical, alkylene oxides, pyridine compounds, aromatic aldehydes, acetaldehyde and/or a bismuth compound.
Claims8
An electroplating bath for the electrodeposition of lead and lead-tin alloys comprising an aqueous solution containing the metal or metals as a lower alkylsulfonate salt, a soluble alkylsulfonic acid in a sufficient amount to give a pH below about 3 to the bath, an aromatic aldehyde and a soluble bismuth compound in a sufficient amount to extend current density range for producing bright deposits.
An electroplating bath for the electrodeposition of lead-tin alloys comprising an aqueous solution containing lead and tin as soluble alkyl-sulfonates, a sufficient amount of a soluble alkylsulfonic acid salt to impart a pH value below about 3 to said bath, and an aromatic aldehyde and a soluble bismuth compound in a sufficient amount to extend current density range for producing bright deposits.
A method for electroplating lead and lead-tin alloys which comprises immersing a substrate to be plated into an electroplating bath comprising an aqueous solution containing lead and tin as soluble alkyl-sulfonates, a sufficient amount of a soluble alkylsulfonic acid salt to impart a pH value below about 3 to said bath, and an aromatic aldehyde and a soluble bismuth compound in a sufficient amount to extend current density range for producing bright deposits.
Dependencies are inferred from the claim text.