摘要:
A tin and/or lead electroplating bath is free from fluoride or fluoborate ions and comprises
(A) a bath-soluble metal salt which is a stannous salt, a lead salt, or a mixture of stannous and lead salts; (B) an alkane sulphonic acid or alkanol sulphonic acid; (C) a nonionic, cationic or amphoteric surfactant; (D) a primary brightening agent which is an aromatic aldehyde, an acetophenone or a carbonyl compound of the formula: in which Ar is a substituted or unsubstituted phenyl, naphthyl, pyridyl, thiophenyl or furyl group; and (E) a secondary brightening agent which is a lower aliphatic aldehyde or a substituted olefin of the formula: in which R, is a carboxy, carboxamide, alkali metal car boxylate, ammonium carboxylate, amine carboxylate or allyl carboxylate group; and R 2 , R 3 and R 4 are each independently hydrogen or lower alkyl groups.
摘要:
A tin and/or lead electroplating bath is free from fluoride or fluoborate ions and comprises (A) a bath-soluble metal salt which is a stannous salt, a lead salt, or a mixture of stannous and lead salts; (B) an alkane sulphonic acid or alkanol sulphonic acid; (C) a nonionic, cationic or amphoteric surfactant; (D) a primary brightening agent which is an aromatic aldehyde, an acetophenone or a carbonyl compound of the formula: in which Ar is a substituted or unsubstituted phenyl, naphthyl, pyridyl, thiophenyl or furyl group; and (E) a secondary brightening agent which is a lower aliphatic aldehyde or a substituted olefin of the formula: in which R, is a carboxy, carboxamide, alkali metal car boxylate, ammonium carboxylate, amine carboxylate or allyl carboxylate group; and R 2 , R 3 and R 4 are each independently hydrogen or lower alkyl groups.