PREPARATION OF PLANOGRAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To prevent the lowering of printing resistance which is caused in the case of <=4 g/m2 amount of anodically oxidized aluminum in a planographic printing plate using an aluminum sheet as the substrate and utilizing a silver complex salt diffusion transfer process. SOLUTION: In preparation in which a planographic printing plate having physical developing nuclei between an anodically oxidized aluminum substrate and a silver halide emulsion layer and utilizing a silver complex salt diffusion transfer process is subjected to at least development after exposure, the amount of anodically oxidized aluminum in the planographic printing plate is <=4 g/m2 and polyacrylic acid is contained in a developer used.