Eastman-kodak Company

Keith H Stephen

Stuart T Gordon

Richard P Szajewski

David George Foster

Mary Ellen Craver

John M Buchanan

Sidney J Bertucci

William G Henry

Eric R Brown

Patrick H Saturno

Gerhard Popp

Manuel A Santos-Rosario

Celia Ann DeAndrea

Mary Morris Podhorecki

Carol J MacDonald

A composition for bleach-fixing a silver halide photographic element comprising a fixing agent and a ternary ferric-complex salt formed by a tetradentate ligand and a tridentate ligand and a method of bleach-fixing using said composition.

Photographic processing solution containing ternary ferric-complex salts

This invention provides an accelerator for peracid bleaches used for bleaching silver halide photographic elements. The accelerator is a complex of ferric (Fe III) ion and a 2-pyridinecarboxylic acid or a 2,6-pyridinecarboxylic acid. The accelerator may be contained in the bleaching solution, a solution preceding the bleaching solution or in the photographic elements themselves.

Photographic peracid bleaches with ferric 2-pyridinecarboxylate and

A method of treating a seasoned fixing solution comprising desilvering a fixing solution containing a chelating compound represented by Formula I

Fixer additives used in combination with iron complex based bleaches to

Bleach compositions and methods that are improvements over those provided by Fyson, U.S. Pat. No. 4,294,914, are disclosed. A highly preferred bleach composition of this invention (a) has the ferric complex of methyliminodiacetic acid as a bleaching agent, and additionally comprises (b) at least 0.9 mole of acetic acid per liter, (c) from about 15 to about 35 grams per liter of potassium bromide; and (d) has a pH of from about 2.5 to about 4.0. This invention includes the discovery of a synergistic bleaching coaction of a bleach (i) comprising an alkyliminodiacetic acid such as methyliminodiacetic acid, and (ii) which has a pH of from about 3.5 to about 4.5 , and (iii) in which the amount of ferric iron is from about 2 to about 16 grams per liter. This coaction between iron levels and pH was previously unknown and was unexpected. Bleach formulations of this invention can be used in the processing of color photographic materials, such as film.

Photographic bleach compositions and methods of photographic processing

An environmentally advantageous photographic bleaching solution for use in the color processing of photographic elements comprises (1) as a bleaching agent, a potassium salt of a ferric complex of an aminopolycarobxylic acid, (2) as an agent which functions to convert silver to silver halide, a potassium halide, and (3) as an agent which functions to inhibit bleach induced dye formation, a water-soluble aliphatic carboxylic acid. The bleaching solution is especially useful in the processing of photographic elements containing a low pKa, high-activity, yellow-dye-forming coupler in that it serves to effectively avoid the undesirable increase in blue D.sub.min that can occur in such elements as a result of bleach induced dye formation.

Photographic bleaching solution and use thereof in photographic color

Bleaching and bleach-fixing solutions, especially useful in the processing of a photographic color material, contain a bleaching agent comprising a ferric complex of propylenediaminetetraacetic acid and a hydroxy-substituted chelating agent present in an amount sufficient to reduce the formation of ferric propylenediaminetetraacetic acid precipitates. The solutions do not generate unacceptable stain or adversely affect leuco cyan dye recovery or process cleanliness.

Photographic bleaching and bleach-fixing solutions

A bleach-fix sheet for use in color photographic processes comprises a support having thereon a bleaching agent, a fixing agent and a hardened hydrophilic binder. In a preferred embodiment, the bleach-fix sheet is useful to bleach and fix a retained image in a color image diffusion transfer unit.

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Rochester, NY, United States of America

Keith H Stephen