| 摘要 |
PURPOSE:To obtain a lithographic printing plate for electronic photograph, which is excellent in desensitizing property and fatigure resistance in relation to color ink or etchant liquid and free of ground and spot staining by controlling the exposure ratio of photo conductive zinc oxide in the surface of the photo conductive layer of a lithographic printing plate to a given value. CONSTITUTION:The exposure ratio of the photo conductive zinc oxide in the photo conductive surface is controlled to 10% or more to improve the print staining of a lithographic printing plate. As a supporter used, a metal such as conductive zinc, iron, copper, etc., or a base paper may be cited. The photo conductive layer provided to the supporter is composed of a binder (e.g., silicone resin) and a photo conductive substance (e.g., zinc oxide, titanium oxide, etc.) in a photo conductive substance to binder proportion of 3:1-20:1 by weight. The control on the exposure ratio of the zinc oxide in the surface of the photo conductive layer to 10% or more is made by lowering the proportion of the resin binder or properly selecting the composition and viscosity of the monomer. |
