PROCESS FOR ALUNINIUM SURFACE PREPARATION

摘要

A method for treating an aluminum sheet useful for lithography by etching said sheet in an aqueous bath containing up to about 25% of nitric and/or hydrochloric acids and from about 1% to about 25% of an inorganic fluorine containing acid or salt thereof. Said etching step is sequentially followed by electrochemical graining and anodizing process steps.