Patent ID: 6811673
Filing Date: 2004-11-02
Classification: C25D

Abstract:
A process for the electrolytic coating of metals with zinc or a zinc alloy at a current density of from 10 to 400 A/dm2 in which matt surfaces are obtained, which comprises electrodepositing zinc from an electrolyte solution comprisinga) a zinc salt selected from zinc sulfate, an alkanesulfonate of zinc or mixtures thereof, and optionally further metal salts, b) an alkanesulfonic acid or a mixture of an alkanesulfonic acid and sulfuric acid, and c) at least one additive for improving the surface roughness and preventing dendritic edge growth, selected from the group consisting of polyethyleneimines, products obtained by reacting amines with epichlorohydrin, alkyl sulfates having at least 5 carbon atoms, sulfonates, and isethionates, without addition of further conventional additives.