Patent ID: 6682645
Filing Date: 2004-01-27
Classification: B41N,C25F

Abstract:
A process for producing an aluminum support for a lithographic printing plate comprising, in sequence, the steps of:(1) subjecting an aluminum plate to preliminary AC electrochemical roughening in an aqueous solution based on hydrochloric acid using electricity in an amount of 1 to 300 C/dm2; (2) immersing the aluminum plate in an aqueous solution of an acid or an alkali to perform chemical etching or electropolishing with said aluminum plate being used as anode, so that the aluminum plate is dissolved in an amount of 0.01 to 1.5 g/m2; (3) subjecting the aluminum plate to DC or AC electrochemical roughening in an aqueous solution based on nitric acid; and (4) immersing the aluminum plate in an aqueous solution of an acid or an alkali to perform chemical etching or electropolishing with said aluminum plate being used as anode, so that the aluminum plate is dissolved in an amount of 0.01 to 10 g/m2.