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. 09, 1979
Filed:
May. 06, 1977
Immo Boie, Odenthal, DE;
Karl Kuffner, Unterhaching, DE;
Gertrud Kirchhoff, Leverkusen, DE;
Karl-Wilhelm Schranz, Langenfeld, DE;
Abstract
Desirable 2-equivalent yellow-forming couplers in which a 1,3-diazolone-2-ring as splittable group is attached by the nitrogen in its 1-position to the coupling position of the 2-equivalent yellow-forming coupler and in which the diazolone ring has a C.dbd.C double bond adjacent to the nitrogen atom in its 1-position, have improved photographic properties in particular with respect to improved reactivity on chromogenic development and improved stability of the couplers as well as the dyes produced from them on chromogenic development in a photographic material which has been subjected to storage under moist and/or warm conditions.