Photographic elements, the special awareness - contain dyes

摘要

A photographic element having a silver halide emulsion sensitized by dye of the formula I: ##STR1## wherein: R.sup.1 represents a substituted or unsubstituted aromatic or heteroaromatic group, a substituted or unsubstituted alkyl or H;PPR.sup.2 represents a substituted or unsubstituted alkyl, alkenyl, aryl, aralkyl, or H;P PE.sup.1 represents an electron withdrawing group; P PZ represents the non-metallic atoms required to complete a substituted or unsubstituted ring system containing at least one 5- or 6- membered heterocyclic nucleus;PPL.sup.1, L. sup.2, L.sup.5 and L.sup.6 independently represent a substituted or unsubstituted methine;PPm may be 0, 1, 2 or 3;P Pn may be 0 or 1.