| 摘要 |
PURPOSE:To obtain a planographic printing plate which is good in both water retentivity and ink deposition characteristic, obviates scanning and defective inking and has good printing resistance by incorporating a synthetic polymer having a carboxyl group and <=about 15,000 average mol. wt. and gelatin into a layer into which fine particle powder is incorporated. CONSTITUTION:The water soluble polymer contg. the carboxyl group and having the low mol. wt., i.e., <=about 15,000 number average mol. wt. and the gelatin or the gelatin deriv. formed by treating and reforming the gelatin by various methods are incorporated into at least one layer into which the fine particle powder is incorporated. As a result, good sand grains are formed on the surface. The planographic printing plate which is good in both the water retentivity and ink deposition characteristic, obviates the scumming and defective inking and has the good printing resistance is thereby obtd. |
