| 摘要 |
PURPOSE:To obtain a lithographic plate superior in printing resistance, by forming a layer containing a specified amount of hydroquinone and specified physical development nuclei on a silver halide emulsion layer provided on a support, and developing it with an alkali activation processing solution. CONSTITUTION:An antihalation layer containing carbon black and a developing agent, such as 1-phenyl-3-pyrazolidone is formed on a support, and on this layer a high sensitivity silver halide emulsion layer is provided. A nucleus layer containing particles of metal, such as Pd, or its sulfide distributed in this layer and partially protruded out of the surface, hydrophilic colloid particles, such as gelatin particles in <=30wt% of the nucleus particles, and 0.5-1.5g/m<2> hydroquinone in the layer. A nonnucleus layer except this nucleus layer does not contain hydroquinone. The lithographic plate thus obtained is imagewise exposed, developed with an alkali activation processing solution, and subjected to treatment for insensitization to grease to form a printing plate superior in printing resistance. |
