abstract |
A photothermographic element comprising a support bearing at least one heat-developable, photosensitive, image-forming photothermographic emulsion layer comprising: (a) a photosensitive silver halide; (b) a non-photosensitive, reducible source of silver; (c) a chromogenic leuco dye reducing agent; and (d) a binder; wherein the chromogenic leuco dye reducing agent is a chromogenic leuco redox-dye-releasing compound of general formula (a), wherein (i) Cp is a coupler group; (ii) N-D is a photographic developper group; and (iii) R1 is a -C(O)-NH-A-Dye group wherein Dye represents the chromophore of a thermally mobile dye; and A represents a single bond or a divalent linking group of the formula -X-R5-L-, wherein R5 is a divalent hydrocarbon chain containing up to 12 carbon atoms, L is a single bond or a divalent group that binds the chromophore of the thermally mobile dye to R5, and X represents a single bond or an -SO¿2?- group. |