| 摘要 |
PURPOSE:To obtain a direct positive photographic sensitive material having high stability for the lapse of time, providing high maximum density without causing elevation of minimum density even it is exposed to light of low illumination by allowing >=80wt.% of total sensitizer incorporated into a surface latent image type silver halide emulsion to be present in a silver halide particle phase, and keeping a ratio of the total amt. of the sensitizer remaining in a binder phase at a low value. CONSTITUTION:The title photographic sensitive material is a direct positive photographic sensitive material contg. the total amt. of the sensitizer in at least one emulsion layer, contg. >=80wt.% of the total amt. of the sensitizer in a silver halide particle phase, or a direct positive photographic sensitive material having at least one layer of internal latent image type silver halide emulsion on a base. >=80at.% of the total amt. of the sensitizer in the emulsion is allowed to be present in a silver particle phase by using a porous absorbent and/or an ion exchange resin after adding the total amt. of the sensitizer to the emulsion, and/or carrying out washing of the emulsion with water. By this method, the total amt. of the sensitizer remaining in the binder phase is reduced. Thus, positive sensitivity is elevated, reversal negative sensitivity is reduced, and, moreover, the maximum density is increased without causing elevation of the minimum density. |
