Manufacture of a planographic printing plate by making silver halide
申请人:AGFA-GEVAERT N.V.
公开号:US03989522A1
公开(公告)日:1976-11-02
A method for the preparation of a planographic printing plate wherein a photoexposed and developed photographic material containing a pattern of poorly water-soluble silver salt is treated with an aqueous liquid which contains in dissolved state an organic cationic compound or mixture of organic cationic compounds, iodide ions, and a sufficient amount of hydronium ions (H.sub.3 O.sup.+) for creating an acidic medium, said liquid being capable of making an unexposed and undeveloped photographic silver halide material as defined in the disclosure sufficiently receptive for a lithographic ink.
Fixer compositions used in planographic printing containing onium
申请人:AGFA-GEVAERT N.V.
公开号:US04062682A1
公开(公告)日:1977-12-13
A method for the preparation of a planographic printing plate wherein a sheet material comprising an outer hardenable hydrophilic colloid layer on whose surface is concentrated a visible silver image that has been formed thereon from silver halide complexes according to the silver complex diffusion transfer process, is treated with an aqueous lithographic fixer having a pH in the range of 1.0 to 6.5 and containing 1. an iron(III) salt of a polyaminopolycarboxylic acid as oxidizing agent for the silver image, 2. a compound yielding in dissolved state iodide ions as precipitating agent for silver ions, and 3. an organic onium compound.