# US 5,702,874 A · Method of processing photographic silver halide materials

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- Number: US 5,702,874 A
- Document ID: US5702874A
- Status: Granted
- Kind: A
- Application number: 08/722,923
- Filed: 1996-09-27
- Granted: 1997-12-30
- Earliest claimed: 1995-09-29
- Assignees: Eastman Kodak Company
- Inventors: John Richard Fyson; Gareth Bryn Evans
- Web page: https://patentgrep.com/patent/US5702874A

## CPC

- G03C 7/42: Bleach-fixing or agents therefor {; Desilvering processes}
- G03C 7/407: Development processes or agents therefor {(G03C7/3244 takes precedence)}
- G03C 1/035: characterised by the crystal form or composition, e.g. mixed grain
- G03C 2001/03517: {Chloride content}
- Y10S 430/144: Hydrogen peroxide treatment
- G03C: PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES (for photomechanical purposes G03F); PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY (photographic processes characterised by the use or manipulation of apparatus classifiable per se in subclass G03B, see G03B; photomechanical production of textured or patterned surfaces G03F; electrophotography, magnetography G03G)
- Y10S: TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS

## Abstract

High silver chloride photographic materials are processed using a development stop bath containing a sulfite fixing agent, followed by bleaching, fixing and treatment with an oxidizing agent that destroys sulfite ions. No washing or stabilizing steps are used after the treatment with oxidizing agent.

## Claims

### Claim 1

A method of processing an imagewise exposed photographic silver halide material comprising at least two dye image-forming layer units responsive to different regions of the spectrum in which the silver halide in each layer comprises at least 85 mol % silver chloride, and the layer units contain a dye image-forming color coupler,
said method comprising, in sequence, the step of dye image formation, followed by the steps:
(a) treating said material in a bath which stops dye image formation
(b) bleaching said material in a first bleach bath containing hydrogen peroxide as bleaching agent, or a material that provides hydrogen peroxide, and an alkali metal halide,
(c) fixing said material in a fixing bath that contains an alkali metal sulfite or a material that provides sulfite as fixing agent, and
(d) treating said material in a bath containing a colorless oxidizing agent that destroys sulfite ions which bath has a pH of 5 or below, and wherein no washing or stabilizing steps are carried out after step (d).

### Claim 2 (depends on 1)

The method of claim 1 wherein the bath in step (a) contains a fixing agent that will not prevent bleaching in a subsequent bleach bath.

### Claim 3 (depends on 1)

The method of claim 1 wherein said oxidizing agent is hydrogen peroxide or a material that provides hydrogen peroxide.

### Claim 4 (depends on 1)

The method of claim 1 wherein said dye image- forming step is a color development and/or redox amplification step.

### Claim 5 (depends on 1)

The method of claim 1 wherein at least one of the processing baths is replenished.

### Claim 6 (depends on 5)

The method of claim 5 in which either
(i) the replenisher for the fixing bath of step (c) comprises the overflow from the fixer of another processing line, or
(ii) the overflow from the fixing bath of step (c) is used to replenish the fixer from another processing line.

### Claim 7 (depends on 6)

The method of claim 6 wherein the other processing line is used for processing a color negative film.

### Claim 8 (depends on 5)

The method of claim 5 wherein the two baths of steps (a) and (c) are replenished using the same replenisher solution, or the overflow from one bath comprises at least part of the replenisher for the other.

### Claim 9 (depends on 1)

The method of claim 1 carried out by passing said material through a tank containing a processing solution that is recirculated through the tank at a rate of from 0.1 to 10 tank volumes per minute.

### Claim 10 (depends on 1)

The method of claim 1 carried out in a machine wherein the ratio of tank volume to maximum area of material accommodatable therein is less than 11 dm3/m.sup.2.

### Claim 11 (depends on 2)

The method of claim 2 wherein said fixing agent is an alkali metal sulfite or a material that provides sulfite as a fixing agent.