PHOTOGRAPHIC PHYSICAL DEVELOPERS COMPRISING AN IONIC SURFACTANT AND PROCESSES UTILIZING THIS DEVELOPER

摘要

1440631 Photographic physical developer solution ITEK CORP 27 Nov 1973 [26 Dec 1972] 54908/73 Heading G2C A photographic physical developer solution comprises an aqueous solution of a water-soluble silver salt e.g. silver nitrate, a photographic reducing agent for said silver salt containing ferrous ion e.g. a ferrous ammonium sulphate/ferric nitrate containing citric and/or tartaric acid, and an ionic surfactant which is a salt of an alkenylamine having at least eight carbon atoms in the alkenyl group e.g. oleylamine acetate. A salt of a primary alkylamine e.g. dodecylamine acetate and an ethyleneoxide condensate of an aliphatic alcohol may also be present. The physical developer may be used to develop an image of catalytic nuclei, e.g. of Ag, Au, Hg, Pt, Pd, silver sulphide or graphite, such as one obtained by exposure of a light-sensitive material sensitized by silver halide, TiO 2 , ZnO, ZnS, tin oxide, cerium oxide, ferric salt/silver ion, or prefogged lead iodde or arsenic sulphide, or an imaged obtained by the silver salt diffusion process. Examples relate to physical development of a material having TiO 2 in a binder, and of a silver halide material having a low silver content emulsion layer coated on an anodized aluminium support which after development is used as a half-tone lithographic printing plate. A printing plate may also be formed by exposing an integral silver salt diffusion material and amplifying the image obtained using the above physical developer.