| 摘要 |
PURPOSE:To provide high sensitivity in the near infrared region and to reduce stain and fog due to a residual dye by using a specified sensitizing dye. CONSTITUTION:A rhodacyanine dye represented by formula I is added to a photographic silver halide emulsion. In the formula I, Z1 is thiazole or the like, Z2 is a group of atoms required to form a 5- or 6-membered heterocyclic ring contg. N, each of R1, R3 and R4 is alkyl, aralkyl or alkenyl, R2 is alkyl, aralkyl, alkenyl or aryl, X<-> is an acid anion, when the dye has the structure of betaine, X<-> is not present, and m=1 or 2. An example of the dye used is represented by formula 1. |
