PLANOGRAPHIC PRINTING PLATE

摘要

PURPOSE:To provide a planographic printing plate for scanning exposure which uses an aluminum plate as a supporting body, uses silver complex diffusion transfer method, and has excellent picture quality and printing durability. CONSTITUTION:This planographic printing plate has physical development nuclei between an aluminum supporting body which is roughened and anodically oxidized and a silver halide emulsion layer. Such an aluminum plate is used as the supporting body that the number of pits having 0.03-0.30mum diameter is >=500 pieces/100mum<2> and that the average diameter of these pits is 0.05 0.20 p. Further, the silver halide emulsion contains a watersoluble gold compd. A water-soluble irridium compd. is added to the emulsion during emulsifying or physical ageing.