Developing Photographic Silver Halide Materials

1,197,306. Developing photographic silver halide materials. GEVAERT - AGFA N. V. Sept.19, 1967 [Sept.19, 1966], No.42524/67. Divided out of 1,194,334. Heading G2C. An exposed photographic silver halide material having an emulsion of the lith type is developed with a hydroquinone/aldehyde-or ketone-bisulphite developer containing a polymer comprising oxyalkylene units in the presence of an N-vinyl-2- pyrrolidone polymer. The latter may be present in the emulsion or another water-permeable layer of the silver halide material or in the developer, and may be homopolymer or a copolymer with vinyl acetate or sodium acrylate or an iodine complex of such a polymer with molecular iodine. The polymer containing oxyalkylene units may be a homopolymer of an alkylene glycol or of an alkylene oxide or a product of condensing alkylene oxides with other organic compounds. In an Example, a sensitized silver chlorobromide emulsion containing 5-methyl-7-hydroxy-5-triazolo-(1: 5-a)- pyrimidine, cadmium chloride and a poly (N-vinyl- 2-pyrrolidone) is developed with a hydroquinone/ formaldehyde bisulphite developer containing an oxyethylene polymer.