SUPPORTING BODY FOR LITHOGRAPHIC PRINTING PLATE, ITS MANUFACTURE, FORMATION OF PIT, AND LIGHT-SENSITIVE LITHOGRAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To provide a supporting body for lithographic printing plate by which a blanket contamination and a contamination when water is squeezed becomes hard to arise, the printing property when a printing paper having a high moisture absorption is used, can be improved, and the performance retention against a variation of the printing conditions can be performed, its manufacturing method, a pit forming method which can be applied to the manufacturing method, and a light-sensitive lithographic printing plate having those capabilities. ;SOLUTION: This supporting body for lithographic printing plate has small pits being formed by overlapping under a highly dense state a roughness component of which the average pit diameter or the average wavelength is 3 μm-20 μm, and of which the average opening diameter is 0.1-1.0 μm, and a standard deviation for the small pit diameter distribution is 0.3 or lower. For this pit forming method, in an acidic electrolyte solution, an anodizing film-forming treatment is performed on an Al based material, and an uneven shape of the anodizing film/base metal interface is formed, and the pits are formed based on the uneven shape of the interface by performing a chemical surface treatment. For this manufacturing method of the supporting body for lithographic printing plate, the pits are formed by using this pit forming method. Also, for this light-sensitive lithographic printing plate, a light- sensitive layer is formed on the supporting body of the supporting body for lithographic printing plate.;COPYRIGHT: (C)1999,JPO