| 摘要 |
PURPOSE:To make improvement in reproducibility of dots by constituting the above printing plate of a specific ester compd., an alkaline-soluble novolak resin, a compd. which forms a halogen free group by irradiation with active rays, and a discoloring agent which changes the color tone of the decomposition product of this compd. by interacting therewith. CONSTITUTION:A photosensitive layer consisting of the photosensitive compsn. contg. at least the 1, 2-naphthoquinonediazide-4-sulfonate compd. of 2,3,4,3',4',5'- hexahydroxybenzophenone and/or 1, 2-naphthoquinonedizade-5-sulfonate compd., the alkaline-soluble novolak resin, the compd. which forms the halogen free group by irradiation with the active rays, and the discoloring agent which changes the color tone of the decomposition product of this compd. is provided on a base. The photosensitive planographic printing plate which has the excel lent reproducibility of the dots in printing and more particularly the reproducibility of the small dots, has wide development latitude in either of under-developability and over-developability and has the excellent exposing and visible image property is obtd. in this way. |
