Photographic4-or 6-equivalent magenta colour couplers which are less sensitive to adventitious formaldehyde than pyrazolone couplers and which may be used, inter alia, in situations where competing couplers are used have the gen- eralformula:
wherein: A represents the atoms necessary to complete, with the nitrogen atom to which it is attached, a photographic magenta dye-forming colour coupler moiety whose coupling position is inactivated bythe-CHR1R2 group,
R' is an alkyl-O-CO, alkyl-CO, aryl-O-C0, aryl-CO-, -COOH, -NO2 or -CN group in which the alkyl and aryl groups are optionally substituted, and
R2 is one of the groups R1 may represent or an arylcarbamoyl or (substituted aryl)-carbamoyl group.
与
吡唑酮
偶联剂相比,摄影用 4 或 6 等效品红色
偶联剂对偶联
甲醛的敏感性较低,可在使用竞争性
偶联剂的情况下使用:
其中A 代表必要的原子,以便与所连接的氮原子一起构成一个感光品红色
染料成色耦合剂分子,其耦合位置被 CHR1R2 基团灭活、
R'是烷基-O-CO、烷基-CO、芳基-O-C0、芳基-CO-、-COOH、-
NO2 或-CN 基团,其中烷基和芳基任选被取代,以及
R2 是 R1 可代表的基团之一或芳基
氨基甲酰基或(取代的芳基)
氨基甲酰基。