| 摘要 |
PURPOSE:To obtain an organic silver salt, having high sensitivity and capable of providing an image with the high maximum concentration and hardly any fog without reducing development speed, by reacting a compound, such as benzotriazole, with silver nitrate while keeping pH within a specific range. CONSTITUTION:A compound expressed by formula I-III (Z1-Z3 each are atomic group required to form a 5--9-membered heterocylic ring), e.g. benzotriazoles (formula I), 2-mercaptobenzothiazoles (formula II) or hydroxytetraazaindenes (formula III), is reacted with silver nitrate at 10-90 deg.C temperature while keeping pH at >=2, especially with the range of 2.5-10 to afford the aimed organic silver salt. The reaction can be carried out in the presence of a silver ion complex-forming compound (e.g. ammonia or thiocyanate) to control the particle size of the formed organic silver salt. If the organic silver salt is contained in a photosensitive material using a silver halide, the organic silver halide is preferably converted into a hydrophilic binder dispersion (regulated to pH5.5-9.5). |
