| 摘要 |
PURPOSE:To improve the reciprocity law failure of the sensitive material at a low illuminance, and to attain the excellent graininess and the development progress of the sensitive material by constituting the emulsion of an inner nucleus composed of a silver iodobromide particle contg. 1-12mol.% of silver iodide and an external nucleus composed of a silver halide contg. 0-2mol.% of silver iodide. CONSTITUTION:The inner nucleus of a core/shell type silver halide particle is composed of the silver iodobromide particle which is chemically sensitized in the presence of an org. silver halide solvent and contains 1-12mol.% of silver iodide. The external nucleus coating the photosensitive site of a core is composed of the silver halide contg. 0-2mol.%. Namely, the emulsion comprises a part (A) having a high interstitial silver ion concn. in the inner part of the silver halide particle, and as the inner nucleus is chemically sensitized in the presence of the org. silver halide solvent, the part (B) having the high interstitial silver ion concn. is effectively and chemically sensitized. The emulsion has the synergetic effect due to the parts (A) and (B). Thus, the reciprocity law failure of the sensitive material at the low illuminance, and the graininess and the development characteristic of the sensitive material are improved. |
