Photographic element containing a red dye-forming pyrazolotriazole coupler
US6638701B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2002 |
| Grant date | Oct 28, 2003 |
| Priority date | — |
| Expiry date | Dec 17, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/3212
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Disclosed is a photographic element comprising a a light sensitive silver halide emulsion layer having associated therewith a pyrazolotriazole dye forming coupler having formula I in which is and L1 is linked to the C atom;L1 is a carbon atom of the triazole ring, substituted by one or two alkyl or aryl groups;L2 is a chain of one or two carbon atoms that may be further substituted by alkyl or aryl groups;R1 is selected from the group consisting of alkyl groups containing 1-3 carbon atoms;R2 is selected from the group consisting of hydrogen, alkyl and aryl groups;R3 is a substituted carbonyl, carbamoyl, sulfonyl, or sulfamoyl group; andX is H or a coupling-off group. Such an element provides a red dye forming coupler of improved stability.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.