PYRAZOLO MAGENTA COUPLERS USED IN SILVER HALIDE PHOTOGRAPHY

摘要

A magenta-forming photographic coupler is a pyrazolo triazolo of general formula.

where R1 + R2 are each H, halogen or various aliphatic or cyclic substituents; X is H or a coupling releasable group; or R1, R2 or X may form a bis-coupler; or R1 or R2 may link to a vinyl group of a vinyl monomer to form a polymer coupler.
72 specific couplers are shown, and six synthesis methods.
The coupler may be in a silver halide emulsion layer of a photographic material or in a primary amine color developing solution. The material may include other magenta couplers, and/or a phenoxy derivative as a dye stabilizer.
Color development produces good magenta image free from subsidiary yellow absorptions.