Formation of black-and-white silver-containing negative images by a diffusion transfer process
AssigneeFuji Photo Film Co., Ltd.
InventorsYoshihiro Takagi, Katsumi Hayashi
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Abstract
A black-and-white negative image forming process is disclosed using a diffusion transfer type film unit. An exposed silver halide emulsion comprising internal latent image type silver halide grains which have substantially no fogging centers at their surface is processed with a composition comprising a silver halide solvent, a developing agent, a foggant, alkali and a fog promoting agent. The solvent for the silver halide characteristically possesses a solubilizing power for AgBr of from about 2.times.10.sup.-5 to 5.times.10.sup.-3 mol/l in a 0.002 molar aqueous solution.
Claims14
In a method of forming black-and-white silver-containing negative image by a diffusion transfer photographic process using a black-and-white diffusion transfer photographic film unit comprising a plastic support, a silver halide photographic emulsion layer and an image-receiving layer, which unit is imagewise exposed, the improvement which comprises
- (1) processing in a single processing solution comprising a solvent for the silver halide, a developing agent and a fogging promoting agent, whereby an optically negative image develops in said image-receiving layer, said silver halide photographic emulsion being an internal latent image type emulsion having no surface fog centers, and said silver halide solvent having a solubility for silver bromide of a 0.02 molar aqueous solution of about 2.times.10.sup.-5 to 5.times.10.sup.-3 mol/l at 60.degree. C. and at the developing pH;
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- (2) including a foggant in said photographic film unit.
Dependencies are inferred from the claim text.