ELECTROPHOTOGRAPHIC PLANOGRAPHIC PRINTING PLATE

摘要

PROBLEM TO BE SOLVED: To provide an electrophotographic planographic printing plate with an electrically conductive middle layer having no humidity dependence of the surface resistance and high surface smoothness, excellent in abrasion resistance, solvent and water resistances and excellent also in adhesion to the sheetlike substrate and a photosensitive layer. SOLUTION: In the electrophotographic planographic printing plate obtained by disposing an electrically conductive middle layer on the front face of a sheetlike substrate and an electrically conductive layer on the rear side face in such a way that the layers are electrically connected at the edges of the sheetlike substrate and forming a photosensitive layer on the electrically conductive middle layer by coating with a photosensitive material containing zinc oxide and a resin binder, the electrically conductive middle layer is formed by coating the front face of the sheetlike substrate with an electrically conductive coating material containing a polypyrrole and a resin binder in such a way that the coating weight of the polypyrrole is adjusted to 0.05-0.30 g/m2 (expressed in terms of solid matter). When a composite obtained by sticking paper or a plastic film to both faces or one face of metallic foil is used as the sheetlike substrate, a planographic printing plate free of elongation particularly in printing and adaptable to full-color printing is obtained.