Pyrazoloazole series couplers
US5118812A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 1990 |
| Grant date | Jun 2, 1992 |
| Priority date | — |
| Expiry date | Jul 6, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03C7/3825
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A pyrazoloazole series coupler having the following formula (I) ##STR1## wherein R.sub.1 represents a substituent having a Hammett's substituent constant .sigma..sub.p of at least 0.6; PA0 X represents a hydrogen atom or a group capable of being released by the coupling reaction with the oxidation product of an aromatic primary amine developing agent; PA0 Za, Zb and Zc each represents .dbd.CH--, ##STR2## (wherein R.sub.2 represents a hydrogen atom or a substituent), .dbd.N-- or --NH--; PA0 one of Za--Zb bond and Zb--Zc bond is a double bond and the other is a single bond; PA0 when Zb--Zc is a carbon-carbon double bond, this Zb--Zc may form a part of another aromatic ring; PA0 R.sub.1, R.sub.2 or X may be a divalent linking group forming a dimer, or R.sub.1 or R.sub.2 may be a divalent linking group bonded to a polymer main chain to form a polymer, a silver halide photographic material which has at least one layer containing the coupler or a support and a method for processing a silver halide color photographic material with a developer containing an aromatic primary amine developing agent in the presence of the coupler.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.