| 摘要 |
PROBLEM TO BE SOLVED: To provide an aluminum alloy substrate for planographic printing plate excellent in printing durability, ink stain resistance and surface quality. SOLUTION: This substrate is obtained by subjecting an aluminum alloy sheet containing, by mass, 0.2 to 0.5% Fe, 0.04 to 0.20% Si, 0.005 to 0.040% Cu, 0.010 to 0.040% Ti, 0.001 to 0.020% Mg and 0.005 to 0.2% Ni, and Al as rest with inevitable impurities to a surface roughening treatment including an electrochemical surface roughening treatment. In the substrate, the relation among Ni content [Ni], Cu content [Cu] and average surface roughness [Ra] (μm) satisfies the following inequality (1): [Ni]/10+[Ra]/100<=[Cu] (1). |
