| 摘要 |
PROBLEM TO BE SOLVED: To prevent production of silver sludge without inhibiting suppression of physical development and ink receiving property by incorporating succinic acid, its salt or monothioether containing its deriv. into a treating liquid for a lithographic plate which uses a silver complex salt diffusion transfer method. SOLUTION: A treating liquid for a plate making process to develop a lithographic plate by using a silver complex salt diffusion transfer method or to neutralize and stabilize the plate after development contains succinic acid, its salt or monothioether compd. having its deriv. If the thioether compd. has two more thioether groups, the effect as a solvent for silver halides is too strong so that the effect to prevent silver sludge is lost. As for the deriv. of succinic acid, esters with a substituent for a hydrogen atom in a carboxyl group, amide groups with a substituent for a hydroxyl group, and acid anhydride can be used. Salts are not specified and for example, salts of alkali metals such as Na, K, ammonium salt and amine salts can be used. |
