Homogeneous single-part photographic color developing concentrate and method of making

Abstract

An aqueous, homogeneous, single-part color developing concentrate comprises a color developing agent in free base form, an antioxidant for the color developing agent, a buffering agent, and a water-miscible or water-soluble hydroxy-substituted, straight-chain organic solvent present in an a concentration such that the weight ratio of water to the organic solvent is from about 15:85 to about 50:50. This composition is prepared in a unique manner, namely by combining the noted components, and removing the sulfate anions commonly present in color developing agents by precipitation with alkali metal ions, before addition of further components. The concentrate can be used to make a working strength processing solution, or it can be used as a replenishing composition with proper dilution.

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