Photographic silver halide element and process
US4853319A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 1987 |
| Grant date | Aug 1, 1989 |
| Priority date | — |
| Expiry date | Dec 14, 2007 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/30529
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Novel pyrazolone photographic couplers contain in the coupling position a coupling-off group represented by the formula: ##STR1## wherein: L.sub.1 and L.sub.2 individually are unsubstituted or substituted methylene or ethylene; PA1 m and n individually are 0 or 1; PA1 Y is R.sub.1 or ZR.sub.2 ; PA1 R.sub.1 is an unsubstituted or substituted aryl or heterocyclic group, or is a secondary or tertiary carbon group represented by ##STR2## wherein R.sub.3 and R.sub.4 are selected from the group consisting of halogen, R.sub.2 and Z.sub.1 R.sub.b ; wherein Z is O, S, or NR.sub.a ; Z.sub.1 is O, S, or NR.sub.c ; and R.sub.2 is an unsubstituted or substituted alkyl, aryl, or heterocyclic group. R.sub.5, R.sub.6, R.sub.a, R.sub.b and R.sub.c are as defined in the specification. R.sub.3 optionally joins together with at least one of R.sub.4 and R.sub.5 to form one or two alicyclic or heterocyclic rings, which are optionally further substituted; and PA1 X represents the atoms selected from a group consisting of carbon, oxygen, nitrogen, and sulfur atoms necessary to complete a 5-, 6-, or 7-member unsaturated ring. This ring optionally contains further substituents than those indicated above, in…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.