# US 5,565,138 A · Bleach

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 5,565,138 A
- Document ID: US5565138A
- Status: Granted
- Kind: A
- Application number: 08/329,990
- Filed: 1994-10-27
- Granted: 1996-10-15
- Earliest claimed: 1993-11-05
- Assignees: Agfa NV
- Inventors: Norman Klaunzer; Ralf Wichmann; Gustav Tappe; Eltjo Boelema
- Web page: https://patentgrep.com/patent/US5565138A

## CPC

- G03C 7/42: Bleach-fixing or agents therefor {; Desilvering processes}
- 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)

## Abstract

A bleach prepared from an iron (III) complex of a complexing agent of the formula I ##STR1## in which L.sub.1, L.sub.2 mean an optionally substituted alkylene group with 1 to 4 C atoms L.sub.3 means an alkylene group with 1 to 4 C atoms, Z.sub.1, Z.sub.2 mean OH, NH.sub.2, NHR.sub.2, X means N, P.dbd.0, SO.sub.2 H Y.sub.1 means OH, NH.sub.2, NHR.sub.3, NR.sub.3 R.sub.4, SO.sub.3 H, PO.sub.3 H.sub.2, NHCOR.sub.5, R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 mean optionally substituted alkyl or optionally substituted phenyl exhibits excellent bleaching action.

## Claims

### Claim 1

Bleach prepared from an iron (III) complex of a complexing agent of the formula 1 ##STR21## wherein m and n are the same or different and are a number from 1 to 4,
Y.sub.2 is OH or NH.sub.2 and
R.sub.6 is an unsubstituted CH.sub.3 group or a CH.sub.3 group substituted by hydroxy, phenyl or C.sub.1 -C.sub.4 -alkoxy.

### Claim 2 (depends on 1)

Bleach according to claim 1 prepared from an iron (III) complex of a complexing agent of the formula ##STR22##

### Claim 3 (depends on 1)

Photographic processing bath with bleaching action characterised by an effective content of at least one iron (III) complex according to claim 1.

### Claim 4 (depends on 3)

Process for photographic processing having at least the stages (a) color development and (b) bleaching and fixing or bleaching/fixing, characterised in that a processing bath with bleaching action according to claim 3 is used for bleaching or bleaching/fixing.