| 摘要 |
PURPOSE:To obtain a liquid which permits retouching even after a treatment for impartation of a lipophilic property or after printing by incorporating a nonfluorinated betaine type surfactant into the retouching liquid for an offset printing plate with which a silver image is utilized as an ink receptor. CONSTITUTION:A compd. which converts an oxidizing agent of silver and silver ion to a silver complex salt or silver halide like ferric complex salt of an org. acid, for example, ferric complex salt of aminopolycarboxylic acid, is used. This material is the complex of, for example, ferric ion and ethylenediaminetetraacetic acid or the disodium salt thereof. The retouching liquid is prepd. by using such nonfluorinated betaine type surfactant at 0.1-0.5mol per 1l of the retouching agent soln. and >=0.5mol potassium bromide in the soluble amt. and dissolving the same into water or various alcohols. The silver image to which a mercapto compd. for intensifying the lipophilic property is adsorbed is satisfactorily oxidized and the quick retouching is permitted even after the treatment for impartation of the lipophilic property or after printing according to this liquid. |
