ORIGINAL PLATE OF WATERLESS PLANOGRAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To provide an original plate of a waterless planographic printing plate excellent in both image reproducibility and printing resistance by forming a photosensitive layer contg. a diazo compd. and having tensile characteristics after exposure represented by a specified modulus of initial elasticity and a specified breaking extension. SOLUTION: A photosensitive layer and an ink repellent layer are successively laminated on a substrate. The photosensitive layer contains a diazo compd. and has tensile characteristics after exposure represented by 5-75kgf/mm<2> modulus of initial elasticity and >=100% breaking extension. The substrate is preferably a metallic sheet with plated or vapor-deposited Al, Cu or Zn or a plastic film such as a PE, polystyrene or PP film and an Al-base metallic sheet is especially preferable.