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. 19, 1982
Filed:
Jul. 11, 1980
Applicant:
Inventors:
Rolf Steiger, Praroman, CH;
Jean F Reber, Marly, CH;
Assignee:
Ciba-Geigy AG, Basel, CH;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03C / ; G03C / ;
U.S. Cl.
CPC ...
430411 ; 430574 ; 430596 ; 430597 ; 430412 ; 542434 ; 542435 ; 542436 ; 26032615 ; 2602 / ; 546176 ; 546121 ; 544345 ; 548156 ; 548146 ; 548219 ; 548328 ; 430573 ;
Abstract
Direct-positive photographic material which has at least one layer which contains a silver halide emulsion surface-fogged by chemical means or by exposure and, as a sensitizer, a trinuclear tetramethinecyanine dye in which all or some of the methine hydrogen atoms have been replaced by fluorine, chlorine, bromine or iodine atoms. The novel trinuclear tetramethinecyanine dyes impart an excellent blue-sensitivity to the photographic materials. Furthermore, high maximum densities and very low minimum densities are achieved.