| 摘要 |
PURPOSE:To obtain a photosensitive material high in sensitivity, superior in image quality, and good in image tone after processing it by forming a silver halide emulsion layer contg. flat silver halide grains contg. silver iodine grains having a diameter to thickness ratio of >=5 on at least one side of a support. CONSTITUTION:The speed of addition of both water-soluble silver salt and halide are increased as silver halide grains grow in preparing flat silver halide grains in order to regulate the diameter distribution of silver halide grains into a monodispersion state, and to shorten their addition and mixing time. The upper limit of the addition speed is the max. flow rate not producing fresh silver halide crystal nuclei, and a pH of 1.5-10 and ammonia or the like as a growth accelerator are used. The silver halide grains are prepared in the temp. range of 35- 90 deg.C. The flat silver halide grains has a thickness of <=500nm, and a diameter to thickness ratio of >=5, and the flat grains amount to >=50wt% of the total grains. Silver halide grains having internally fogged nuclei are incorporated in a constituent layer on the side same as the silver halide emulsion layer, and a fluorinated surfactant is also added to a constituent layer. |
