Ferrous photographic bleach-fixing precursor compositions and methods for their use

摘要

Stable, single-part photographic bleach-fixing "precursor" compositions comprise one or more iron-ligand complexes, one or more thiosulfates as the sole fixing agents, and optionally, a sulfite preservative. At least 50 mol % of the iron in the composition is in the form of Fe(II). This composition can be used directly in photoprocessing, or used as a regenerator when mixed with bleach-fixing overflow to provide a replenishing solution. Because the Fe(II) compounds are precursor bleaching agents, they must be oxidized to Fe(III) for active bleaching prior to or during the photographic processing operations. <IMAGE>