PROCESS FOR THE FORMATION OF NEGATIVE COLOUR IMAGES ACCORDING TO THE SILVER DYE-BLEACHING PROCESS, AND THE SILVER DYE-BLEACHING MATERIAL USED IN THIS PROCESS

摘要

Negative color images are produced by the silver dye bleach process, by exposure of a photographic silver dye bleach material, silver developing, dye bleaching, silver bleaching and fixing, the silver bleaching being optionally carried out simultaneously with the dye bleaching and/or the fixing, in a single treatment bath. The photographic material consists of a support with at least one layer assembly of three layers in each case, each layer assembly containing, as viewed from the same side as the incident light: (a) a first layer which contains a highly sensitive and optionally spectrally sensitized silver halogenoiodide emulsion, (b) an intermediate layer containing neither silver halide nor image dye, and (c) a third layer which contains a bleachable image dye and a core-shell emulsion which is free of iodide or has a low iodide content, the particles of which emulsion consist of a surface-fogged silver halide core optionally treated with a developing retarder, and of a silver halide shell enclosing the said core, and the material, in the case where it contains more than one layer assembly, contains optionally intermediate layers (d) between the layer assemblies. The material according to the invention is distinguished by enhanced sensitivity and increased contrast in the positive silver image. The developing is carried out in a developer solution which does not contain any silver-complexing agents.