| 摘要 |
PURPOSE:To prevent dirt on entire background and spot dirt even at printing, by incorporating photoconductive zinc oxide, insulating resin and polyvalent metallic salt to an image reception layer of a lithographic printing thick plate and coating aq. polymer solution contg. alginate on this layer. CONSTITUTION:An image reception layer contains photoconductive zinc oxide, insulating resin and polyvalent metallic salt. As the insulating resin, resin such as acrylic, polyester, styrene, alkyd, urethane, vinyl acetate, and polyvinylchloride or their copolymer resin, and as the polyvalent metallic salt, >= divalent metal is used and hydrochloride, nitrate and other salt of Cu, Ba, Ca and Zn can be used. On the original plate, 0.1-3% ammonium or sodium alginate or a composition contg. dispersed aluminum oxide or silicon oxide in said aq. solution is coated. |
