Patent ID: 7393626
Filing Date: 2008-07-01
Classification: G03C

Abstract:
1. A black-and-white photothermographic material that forms a black-and-white image by a silver image, the black-and-white photothermographic material comprising, on one surface of a substrate, photosensitive silver halide grains having a core/shell structure, a non-photosensitive organic silver salt, a reducing agent and a binder, wherein said photosensitive silver halide grains include at least iridium and a metal selected from the group consisting of iron, copper, rhodium and ruthenium, an amount of iridium in the silver halide grains is from 1×10 −8 to 1×10 −2 mol per 1 mol of silver halide, an amount of the metal selected from the group consisting of iron, copper, rhodium and ruthenium in the silver halide grains is from 1×10 −8 to 1×10 −2 mol per 1 mol of silver halide, and 90% or more of a total iridium amount contained in the silver halide grains is contained in a core portion of the grain providing that, the core portion of the grain corresponds to 50% of the total mol % of silver halide in the grain, and at least 50% of a total amount of the metal selected from the group consisting of iron, copper, rhodium and ruthenium contained in the silver halide grains is contained in the shell portion of the grain, wherein the reducing agent is a bisphenol compound represented by the following formula (R): wherein, in formula (R), R and wherein the silver halide is silver bromide, silver iodobromide or silver iodide.