Additive compositions, baths, and methods for electrodepositing bright zinc deposits

摘要

A composition as described which is useful particularly in improving the electrodeposition of bright zinc from aqueous acidic plating baths. The new composition comprises a reaction product obtained by the process of preparing an intermediate composition by reacting formaldehyde in water with sulfamic acid and at least one aliphatic acyclic amine containing at least one primary amine group, and thereafter reacting said intermediate compound with at least one epihalohydrin or glycerol halohydrin or mixtures thereof. Aqueous acidic zinc plating baths containing the additive compositions of the invention and methods for depositing a bright zinc coating over a wide range of current densities also are described.