emulsion for a photothermographisches material, method for the production of a photothermographischen material and a aufzeichnungsverfahren

摘要

PROBLEM TO BE SOLVED: To obtain the photothermographic material exhibiting a low fog level and improved gradation through imagewise exposure and heat development by incorporating a specified polyhalogenated compound in an emulsion and also a reaction compound between this compound or a reducing agent present in this emulsion. SOLUTION: This emulsion comprises a substantially photononsensitive organic silver salt and a photosensitive silver halide catalytically associated with this organic silver salt and a binder, and this emulsion contains the polyhalogenated compound selected from a group comprising quaternary ammonium polyhalide and quaternary phosphonium polyhalide and the like satisfying a prescribed test and a reaction product between this polyhalogenated compound and a reducing agent present in this emulsion. The method for manufacturing this photothermographic material comprises a heat-developable element containing the emulsion capable of forming an image without prheating before exposure.