(57) This invention relates to heat-developable photographic materials, i.e., photothermographic materials. It has been described in the patent literature to transfer a dye image formed in a photothermographic system by means of a transfer solvent.
It would be desirable to provide a photothermographic material capable of producing multiple color images, wherein image development, including dye transfer, can be carried out without the use of liquids. This invention provides a photothermographic article comprising (a) an image-receiving element comprising a polymeric image-receiving layer, (b) strippably adhered to said image-receiving element, an imageable photothermographic element comprising a plurality of emulsion layers, each of which emulsion layers comprises a binder, a silver source material, photosensitive silver halide in catalytic proximity to the silver source material, and a leuco dye, and (c) interposed between each pair of said emulsion layers, a dye-permeable interlayer. The dyes formed in each emulsion layer, i.e., magenta dye in the green sensitive layer, yellow dye in the blue sensitive layer, and cyan dye in the red sensitive layer, migrate through the interlayers and the emulsion layers to the image-receiving layer as the photothermographic article is heated for development. Dye formation and dye transfer can be carried out without the aid of any transfer solvent or wet chemicals. After development by heat, the imageable photothermographic element, which is strippably adhered to the image-receiving layer, can be peeled away from the image-receiving layer and discarded.