flachdruckplattentru00e4ger, procedures to its production and flachdruckplattenvorlu00e4ufer

摘要

The invention provides a method for producing a support for planographic printing plates which comprises a step of roughening the surface of an aluminum plate and in which the surface-roughening step includes (1) a pre-electrolytic surface-roughening step of electrolytically roughening the surface of an aluminum plate in an aqueous hydrochloric acid solution, (2) an alkali-etching step of etching the roughened surface of the aluminum plate with an alkali solution, (3) a desmutting step of contacting the etched aluminum plate with an aqueous sulfuric solution having predetermined sulfuric acid and aluminum ion concentrations at a predetermined temperature for 1 to 180 seconds, and (4) an electrolytic surface-roughening step of processing the desmutted aluminum plate in an aqueous nitric acid solution with an alternating current being applied thereto. The invention enables stable and inexpensive production of planographic printing plate supports even from regenerated aluminum. IMAGE