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:
Nov. 24, 1981
Filed:
Jul. 24, 1980
Applicant:
Inventor:
Graham Evans, Galleywood, GB;
Assignee:
Ciba-Geigy AG, Basel, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
542461 ; 430523 ;
Abstract
New optical brightening agents and photographic materials which contain in at least one layer these brightening agents are provided. The compounds have the general formula ##STR1## wherein R.sub.1 and R.sub.3 are hydrogen or methyl, R.sub.2 and R.sub.4 are alkyl R.sub.5 is hydrogen, alkyl, aryl, aralkyl, X is --NH--, --O-- or --S--, L.sub.1 and L.sub.2 are alkylene oxide chains and M.sup..sym. is a hydrogen or an alkali metal cation. These brightening agents enhance the brightness in the white areas of photographic print materials.