| 摘要 |
PURPOSE:To obtain an image easily soluble and high in gradation reproducibility, and high in contrast by using a specified photosensitive polyvinylalcohol deriv. mixed with a wax emulsion. CONSTITUTION:A PVA deriv. used as a photosensitive element has 200-4,000 main chain polymn. degree and 70-98mol% saponification degree, and contains styryl-pyridinium or styrylquinolinium groups as polymn. monomer units in an amt. of 0.3-40mol% of the total monomer units. Said PVA has formula I in which Y is formula II or III; R1 is alkyl or aralkyl optionally substd. by at least one of OH, CONH2, or a group having an ether bond or unsatd. bond; R2 is H or lower alkyl; X<-> is an anion; (m) is 0 or 1; and (n) is 1-6. Such a photosensitive element is mixed in a wax emulsion in a weight ratio of (1/0.5)-1/5. Further, 0.01-1wt% colloidal soln. of silicic acid anhydride polymer represented by the formula: XSi(OR)3 (X being amino, vinyl, or the like, and R being methoxy or the like) to enhance adhesion of an image part and its physical strength. |
