摘要 |
<p>A photosensitive silver halide emulsion is disclosed which is spectrally sensitized with a dye combination comprising a symmetrical benzoxazolocarbocyanine dye of the formula: I. wherein R represents hydrogen or a lower alkyl group possessing from 1 to 3 n carbon atoms, inclusive; and each R1 represents a carboxyalkyl or sulfoalkyl group possessing from 1 to 4 carbon atoms, inclusive, in the alkylene chain; Y represents an anion; and n represents O or 1, with n=0 in the inner salt form of the dye; and an unsymmetrical benzimidazolocarbocyanine dye of the formula: II. wherein Y and n possess the same meaning as in Formula I; X is S or Se; R2 is a lower alkyl group possessing from 1 to 3 carbon atoms inclusive; R3 and R4 are the same or different and represent a carboxyalkyl or sulfoalkyl group, each possessing from 1 to 4 carbon atoms, inclusive, in the alkylene chain, or a lower alkyl group, with at least one of R3 and R4 being said carboxyalkyl or sulfoalkyl group; R5 is halogen, cyano, or lower carboxyalkyl; R6 is hydrogen or halogen; and Z represents the non-metallic atoms necessary to complete a benzothiazole or benzoselenazole nucleus. The dye combination imparts, in silver halide, a highly desirable and stable sensitivity to the green region of the spectrum.</p> |