To obtain a new compound excellent in the color sensitization in green color short wave region and useful as a photosensitive coloring matter subject to spectral sensitization in high sensitivity without deteriorating the storage stability of silver halide emulsions.
This new compoind is shown by formula I (R1 to R4 are each an aliphatic group; V1 to V4 are each H or the like; X is an ion necessary of neutralizing intermolecular electric charge; (n) is a number necessary for neutralizing intermolecular electric charge; with a proviso that at least one of R1 to R4 is a group of the formula L-Q, at least one of the others being a sulfoalkyl; L is an alkylene which may be interposed with a chalcogen; Q is a heterocycle), e.g. a compound of formula II. The compound of formula I can be synthesized based on a conventionally known method; for example, for the compound of formula II, it is obtained by reaction between a compound of formula III and a compound of formula IV in dimethyl sulfoxide in the presence of 1,8-diazabicyclo [5,4,0] undec-7-ene.
FUKUSAKA KIYOSHI
KAGAWA NOBUAKI
