Photographic silver halide materials and process comprising a pyrazolotriazole coupler
US5645981A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 6, 1994 |
| Grant date | Jul 8, 1997 |
| Priority date | — |
| Expiry date | Apr 6, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/3835
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Novel pyrazolotriazole dye-forming couplers contain an aliphatic or aromatic aryl ballast group and having one carboxy or sulfonic group on the ballast group enabling the pyrazolotriazole to have increased activity and having an ether (--O--) group or group A bonded directly to a carbon atom or arylene group that is bonded directly to the pyrazolotriazole nucleus and wherein the pyrazolotriazole is capable of forming an immobile dye in a gelatino silver halide emulsion and is free of coupling-off groups that reduce silver. When the ballast group is bonded to the pyrazoloazole nucleus by means of an aromatic group, the aromatic group is ortho substituted. Group A is ##STR1## --S--, --SO--, --SO.sub.3 --, or --OSO.sub.2 --. The ether group or group A enables the dye formed to have desired hue. These couplers are useful in photographic silver halide materials and processes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.