Process for making decorative or informative patterns on objects made of metal sheets with one or possibly several coatings

摘要

According to the invention a method for producing decorative or informative patterns on objects made of plated metal sheets is disclosed. The procedure is to remove the outer plated layer mechanically or chemically as far as at least one of the lower layers in the shape of the desired pattern. The object thus obtained, with the exposed lower layer or layers, is then treated in one and the same surface treatment bath, with which the outer and the inner layers react differently. It is advantageous to use aluminum of different degrees of purity for plated layers and to use a polishing bath for the surface treatment.