Lithographic printing plate material improved in water retention characteristics.

摘要

Printing endurance of a lithographic printing plate made by using silver complex diffusion transfer process is markedly improved and besides staining which occurs during printing can be effectively inhibited by containing in at least one of a layer which contains nuclei for physical development comprising a heavy metal or a sulfide thereof and a layer contiguous to said layer at least one water-soluble synthetic polymer having the following structural units: <CHEM> wherein A:B = 100:0 - 50:50 (molar ratio) C:D = 100:0 - 50:50 (molar ratio) (A+B):(C+D) = 95:5 - 5:95 (molar ratio) and R1 represents a hydrogen atom or an alkyl group of 1-6 carbon atoms, R2 represents a hydrogen atom or an alkyl group of 1-20 carbon atoms, R3 represents an alkyl group of 1-20 carbon atoms and M represents a hydrogen atom or a cation.