PURPOSE: To obtain an image receiving layer having higher smoothness to form a sharp image without disconnection of lines by a method wherein the image receiving layer consisting of a photoconductive zinc oxide, a binder, and a lead oxide sensitizing dye and having a surface roughness of 1.10μm or less by a center line average height Ra is provided on a water-resistant substrate.
CONSTITUTION: An original plate 1 for thermal transfer lithographic printing is provided with an image receiving layer 3 on a water-resistant substrate 2. A thermal transfer ribbon 4 is provided with a plate-making image forming material 5 on the surface of a transfer base film 6. Liquid obtained by mixing and dispersing a photoconductive zinc oxide, a binder, a lead oxide sensitizing dye, and an adjuvant in an organic solvent, such as toluene, by a ball mill or the like is applied on the water-resistant substrate and dried to form the photosensitive layer on the water-resistant substrate of the lithographic printing original plate 1. Moreover, the layer is calendered to make the surface smooth. In this manner, a lithographic printing master for electrophotographic plate making can be obtained. In this manner, a lithographic printing original plate ensuring a sharply printed matter can be produced.
UEDA HITOSHI
SUGIYAMA SHOICHI