| 摘要 |
PURPOSE:To improve the photosensitivity of the title material in from a red color region to an infra-red region, and to lessen the characteristic change of the photosensitive material at the time of preserving the coating solution by incorporating a specified compd. in the silver halide contd. in a silver halide emulsion layer, and then aging the obtd. emulsion layer, and by composing the silver halide emulsion layer of silver chloroiodobromide contg. a prescribed amount of silver chloride. CONSTITUTION:The compd. shown by formula I is incorporated in the silver halide contd. in the silver halide emulsion layer, and then the obtd. emulsion layer is aged. The silver halide contd. in the silver halide emulsion layer is composed of the silver chloroiodobromide contg. 50mol% of the silver chloride. In the formula, R1-R3 are each hydrogen atom or a substituting group, X<-> is an anion. The tetrazolium compd. shown by formula I is incorporated in the photosensitive material in an amount of about >=1mg and up to 10g, preferably about >=10mg and up to about 2g per 1mol of the silver halide. Thus, the sensitivity of the photosensitive material in from the red color region to the infra-red region and the contrast of said material are improved, and the characteristic change of the photosensitive material at the time of preserving the coating solution, is lessened. |
