Method for producing supports for lithographic printing plates
AssigneesFuji Photo Film Co., Ltd., Nippon Light Metal Company, Ltd.
InventorsHirokazu Sasaki, Akira Morita, Takemasa Yamamoto
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Abstract
A method for producing a support for a lithographic printing plate is described, which comprises mechanically graining the surface of an aluminum sheet, and then electrolytically graining the surface of the aluminum sheet in a solution containing hydrochloric acid, nitric acid, or a mixture thereof by applying thereto an alternating current in such manner that the ratio the quantity of electricity during the cathodic period to the quantity of electricity anodic period is in the range of from 1.0/1 to 2.5/1.
Claims5
A method for producing a support for a lithographic printing plate which comprises mechanically graining the surface of an aluminum sheet, and then electrolytically graining the surface of the aluminum sheet in a solution containing hydrochloric acid, nitric acid, or a mixture thereof by applying thereto an unsymmetrical alternating current in such manner that the ratio of the quantity of electricity during the cathodic period to the quantity of electricity during the anodic period is in the range of from 1.0/1 to 2.5/1 and the quantity of electricity during the anodic period is 300 coulombs/dm.sup.2 or less.
Dependencies are inferred from the claim text.