Method for making improved lithographic printing plate

Claim 1

A method of printing with lithographic printing plate made by the silver complex diffusion transfer process comprising diffusion tranferring a diffusible silver complex formed from undeveloped silver halide in an imagewise exposed silver halide emulsion layer and a silver halide complexing agent to a physical development nuclei layer and developing it there to form a transferred silver which is utilized as an ink-receptive area, and wherein the diffusion transfer development treatment is carried out in the presence of at least one thione compound having a non-enolizable thione group, an adjacent nitrogen atom with an attached substituent R and represented by N-R, and a group of atoms which may carry the substituent R, said group of atoms being necessary for forming a 5- or 6-membered ring having no aromatic condensed ring, said substituent R is selected from the group consisting of alkyl, alkoxyalkyl, aminoalky, hydroxyalkyl, carboxyalkyl, acyloxyalkyl, sulfoalkyl, haloalkyl, allyl, amino, alkylamino, dialkylamino, acylamide, hydroxyl, acyloxy, alkylthio, and alkoxy groups which have no carbon atom or have 1 to 3 carbon atoms and then applying ink to the printing plate.

Claim 2

A method of printing with lithographic printing plate made by the silver complex diffusion transfer process comprising diffusion tranferring a diffusible silver complex formed from undeveloped silver halide in an imagewise exposed silver halide emulsion layer and a silver halide complexing agent to a physical development nuclei layer and developing it there to form a transferred silver which is utilized as an ink-receptive area, and wherein the diffusion transfer development treatment is carried out in the presence of at least one thione compound having a non-enolizable thione group, an adjacent nitrogen atom with an attached substituent R and represented by N-R, and a group of atoms which may carry the substituent R, said group of atoms being necessary for forming a 5- or 6-membered ring having no aromatic condensed ring, said substituent R is selected from the group consisting of alkyl, alkoxyalkyl, aminoalky, hydroxyalkyl, carboxyalkyl, acyloxyalkyl, sulfoalkyl, haloalkyl, allyl, amino, alkylamino, dialkylamino, acylamide, hydroxyl, acyloxy, alkylthio, and alkoxy groups which have no carbon atom or have 1 to 3 carbon atoms and then applying ink to the printing plate.