MANUFACTURING METHOD OF ALUMINUM SUPPORT FOR PLANOGRAPHIC PRINTING PLATE MATERIAL, ALUMINUM SUPPORT FOR PLANOGRAPHIC PRINTING PLATE MATERIAL, AND PLANOGRAPHIC PRINTING PLATE MATERIAL

摘要

Disclosed is a manufacturing method of an aluminum support for a planographic printing plate material, which comprises electrolytically surface-roughening an aluminum plate in an electrolytic solution containing mainly hydrochloric acid at current density of from 35 to 150 A/dm² and at a quantity of electricity of from 600 to 1500 A·second/dm², employing AC, etching the surface-roughened aluminum plate so that the dissolution amount of the aluminum is from 3 to 5 g/m², electrolytically surface-roughening the resulting aluminum plate in an electrolytic solution containing mainly hydrochloric acid at current density of from 15 to 30 A/dm² and at a quantity of electricity of from 100 to 400 A·second/dm², employing AC, desmutting smut produced on the aluminum plate in an acidic solution containing mainly phosphoric acid, so that the amount of the smut remaining undissolved is from 0.05 to 0.3 g/m², and anodizing the desmutted aluminum plate in that order.