Abstract: An aqueous acidic plating bath for electrodeposition of tin, lead or tin-lead alloys on a substrate is described. The plating baths are free of fluoborate and comprise (a) at least one bath-soluble metal salt selected from the group consisting of a stannous salt, a lead salt, or a mixture of stannous and lead salts, (b) at least one alkane sulfonic acid or alkanolsulfonic acid, (c) at least one nonionic, cationic or amphoteric surfactant, (d) an effective amount of at least one primary brightening agent selected from the group consisting of aromatic aldehydes, acetophenones, and carbonyl compounds having the general formulaAr--C(H).dbd.C(H)--C(O)--CH.sub.3 (III)wherein Ar is a phenyl, naphthyl, pyridyl, thiophenyl or furyl group, and (e) an effective amount of a secondary brightening agent selected from the group consisting of lower aliphatic aldehydes and substituted olefins of the formula ##STR1## wherein R.sub.

Abstract: The present invention provides an ammonia-free acid zinc plating bath for electrodepositing bright zinc on a substrate in which the zinc deposit produced thereby is ductile and presents a glossy to bright coating on the substrate over a wide cathodic current density range. The ammonia-free acid zinc plating baths of the invention comprise zinc ions, chloride ions, at least one polyoxyalkylated naphthol, at least one aromatic carboxylic acid or bath-soluble salt thereof, and at least one anionic aromatic sulfonic acid or bath-soluble salt thereof. In addition to the above components, the ammonia-free acid zinc plating baths of the invention may contain at least one nonionic polyoxyethylene compound and at least one aromatic aldehyde, ketone, or mixtures thereof. The ammonia-free acid zinc plating baths of the invention are free from significant amounts of complexing agents that would impede the removal of zinc ions from the baths prior to disposal.