Method of manufacturing a support for a lithographic printing plate

摘要

Disclosed is a method of manufacturing a support for a lithographic printing plate, which method includes: a casting step in which an aluminum alloy melt is fed between a pair of cooling rollers by a melt feed nozzle and is rolled as it is being solidified by the pair of cooling rollers, forming an aluminum alloy plate, and a graining treatment step in which a surface of the aluminum alloy plate is subjected to graining treatment which includes at least alkali etching treatment and subsequent electrochemical graining treatment, thereby giving a support for a lithographic printing plate; wherein the surface of the aluminum alloy plate on the side which is subjected to the graining treatment undergoes an amount of aluminum dissolution X per square meter (g/m<2>) during the alkali etching treatment and has a total amount of electricity Y per square decimeter (C/dm<2>) applied thereto during an anode reaction in the electrochemical graining treatment such as to satisfy formula (1) below: 1,000 > Y ≥ 10x (1). By using this method, a support for a lithographic printing plate which is free of surface mottling is provided.