| 摘要 |
PURPOSE:To improve gradation without decreasing sensitivity and printing durability by successively forming specified two kinds of positive photosensitive layers on a supporting body. CONSTITUTION:A positive photosensitive layer (a) containing an o-quinone diazide compd. in which its diazo groups are isolated, and a positive photosensitive layer (b) containing an o-quinone diazide compd. are formed in the order of (a) and (b) on a supporting body. More preferably, the proportion of radicals of diazo groups in the o-quinone diazide compd. in the positive photosensitive layer (a) is 1-80mol% of the whole diazo groups in the o-quinone diazide compd. As for the coating method for the upper layer (b), it is preferable to use a water, hydrocarbon or alcohol-base solvent as a coating solvent to disperse the photosensitive liquid. The photosensitive liquid is dispersed, for example, by using a ball mill, sand grinder, roll mill, three-roll method, high pressure homogenizier, ultradisperser, bubble homogenizer or the like. |
