Fixer additives used in combination with iron complex based bleaches to prevent iron retention
AssigneeEastman Kodak Company
InventorsMary E. Craver, Janet M. Huston, Robert J. Opitz
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Abstract
A method of processing an image wise exposed and developed silver halide photographic element comprising bleaching the photographic element in a bleaching or bleach-fixing solution containing as the primary bleaching agent a complex of ferric ion and a tridentate or a tetradentate ligand, and then processing the photographic element in a solution containing a chelating compound represented by Formula I HOOC(CH.sub.2).sub.m (X) ((CH.sub.2).sub.n COOH).sub.2 (I) where X is N, or C--OH; n and m are independently 0, 1, or 2; and M is a cationic ion.
Claims18
A method of processing an imagewise exposed and developed color silver halide photographic element comprising bleaching the photographic element in a bleaching or bleach-fixing solution having a pH greater than 3.0 and containing as the bleaching agent a complex of ferric ion and a tridentate or a tetradentate aminopolycarboxylic acid ligand and then processing the photographic element in a solution containing a biodegradable chelating compound represented by Formula I
- MOOC(CH.sub.2).sub.m (X)((CH.sub.2).sub.n COOM).sub.2 (I)
- where
- X is N, or C--OH;
- n and m are independently 0, 1, or 2, and
- M is a cationic counterion.
Dependencies are inferred from the claim text.