| 摘要 |
PURPOSE: To provide a planographic printing plate excellent in chemical resistance and high printing durability even when printing is performed by using UV inks without burning treatment, by applying a coating liquid containing a specified compd. on a supporting body and then drying it. CONSTITUTION: This positive photosensitive planographic printing plate is obtd. by applying a coating liquid on a supporting body and then drying it. The coating liquid contains a polymer compd. having sulfone amide groups which is insoluble in water but soluble in alkali soln., an alkali-soluble novolac resin, a photosensitive compd. which gives a positive image, and a cyclic lactone. If only the combination of a polymer compd. containing sulfone amide groups and a novolac resin is used, no effect is obtd. By combining these constitutional requirements, the development latitude is significantly improved and high printing durability against UV inks is obtd. The polymer compd. having sulfone amide groups which is insoluble in water but soluble in alkali soln. is a polymer compd. containing -SO2 -NH- bonds in the side chains or the main chain, and a polymer compd. containing -SO2 -NH- bonds in the side chains is preferable. |
