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:
Apr. 28, 1987
Filed:
Nov. 07, 1985
Applicant:
Inventors:
Paul Tschopp, Dudingen, CH;
David G Leppard, Marly, CH;
Assignee:
Ciba-Geigy AG, Basel, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03C / ;
U.S. Cl.
CPC ...
430512 ; 430372 ; 430551 ; 430610 ; 430931 ;
Abstract
Photographic material containing magenta coupler is stabilized by incorporating a dibenzoxaphosphorin of the formula ##STR1## into the emulsion layer containing the coupler or into an adjoining colloid layer. The yellowing on dark storage of such material is substantially reduced as a result. The symbols A and n are defined in claim 1.