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:
Jul. 03, 1990
Filed:
Dec. 09, 1988
Peter Bergthaller, Bergisch Gladbach, DE;
Helmut Haseler, Leverkusen, DE;
Heinz Meckl, Bergisch Gladbach, DE;
Agfa-Gevaert Aktiengesellschaft, Leverkusen, DE;
Abstract
In the case of color materials with the usual processing times, bleaching and bleaching/fixing baths containing an iron(III) ion complex salt as bleach and, in addition, a 5- to 7-membered heterocyclic compound containing at least one N-atom and at least one other hetero atom from the group consisting of O,S,N which is substituted by --S.sup..crclbar. and, at a quaternary ring nitrogen atom, carries a positive charge arranged in such a way that no tautomeric charge compensation to a neutral thione form is possible, provide for good bleaching, i.e. for black areas free from residual silver in the case of color negative materials and for low minimum densities in the case of color reversal materials, by virtue of their excellent bleaching rate and, at the same time, their high stability.