SPECTRAL SENSITIZATION BY POLYMETHINE DYES WHICH CONTAIN AN UNSATURATED ALKYL SULFONIC ACID GROUP

摘要

The invention relates to photographic materials which are optically sensitized with cyanine dyes containing at least 1 nitrogen-containing heterocyclic grouping, the nitrogen of which is substituted with an olefinically unsaturated alkyl sulfonic acid grouping. Such dyes provide more sensitization than corresponding dyes in which the alkyl is saturated.