Silver halide emulsion containing an arylphosphonium salt as antifoggant

摘要

Substances of the structure R1R3<+> ANGLE Z ANGLE X<-> R2R4 wherein Z is phosphorus, X<->is Cl<->, Br<->, ClO2<-> or BF4<->, and R1 - R4 are alkyl or aromatic groups are excellent inhibitors of fog formation when incorporated in photographic emulsions containing silver halides.