The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 18, 1983
Filed:
Jul. 17, 1980
Gerald Jan, Marly, CH;
Ciba-Geigy Ltd., Basel, CH;
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 and alkylammonium and n is an integer from 2 to 4.