Process for the production of colored photographic images by the silver dye-bleach process
US4266011A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 20, 1979 |
| Grant date | May 5, 1981 |
| Priority date | — |
| Expiry date | Sep 20, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/28
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A process for the production of colored photographic images by the silver dye-bleach process by image-wise exposure and subsequent processing by developing the silver image, dye-bleaching and silver bleaching, it being possible, optionally, for the last two steps to be combined, silver fixing and washing, in which process dye-bleaching and/or silver bleaching is carried out in the presence of at least one bleach catalyst of the formula ##STR1## In the formula, A and B are in each case the non-metallic atoms necessary to complete a benzene or pyridine ring, R.sub.1 and R.sub.3 are each hydrogen, hydroxyl, halogen, alkyl, carboxyl, carbalkoxy, carbalkoxyalkoxy, --CH.sub.2 OH, --O(CH.sub.2).sub.n OH, --O(CH.sub.2).sub.2 O(CH.sub.2).sub.2 OH, --CH.sub.2 Cl, --CH.sub.2 Br, --NR.sub.5 R.sub.6, --CH.sub.2 NR.sub.5 R.sub.6, --O(CH.sub.2).sub.n NR.sub.5 R.sub.6, --CH.sub.2 SO.sub.3 M, --O(CH.sub.2).sub.n SO.sub.3 M or --SO.sub.3 M, R.sub.2 and R.sub.4 are each hydrogen, hydroxyl, alkyl or alkoxy and R.sub.5 and R.sub.6 are each hydrogen or alkyl, M is hydrogen, an alkali metal, ammonium or alkylammonium and n is an integer from 2 to 4.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.