Tin, lead, and tin-lead alloy plating baths

Abstract

A tin, lead or tin-lead alloy plating bath, which comprises (A) a principal plating bath containing an alkanesulfonic or alkanolsulfonic acid, and either a divalent tin salt or a divalent lead salt thereof or both; (B) at least one of surfactants comprising (a) a cationic surfactant selected from the group consisting of quarternary ammonium salts, alkyl pyridinium salts, alkyl imidazolinium salts and higher alkyl amine salts, (b) an amphoteric surfactant selected from betaines, or (c) a nonionic surfactant selected from the group consisting of condensation products of ethylene oxide and/or propylene oxide with a styrenated phenol, a higher alcohol, an alkylphenol, an alkylnaphthol, a fatty acid amide, a sorbitan or a phosphate; and (C) at least one of levelling agents selected from the group consisting of alkylidene sulfamic acids, quinolinol derivatives, benzotriazole derivatives, dialkylidene o-phenylene diamines, benzaldehyde derivatives, triazine derivatives, salicylic acid derivatives and nitriles.

Dependencies are inferred from the claim text.