| 摘要 |
PURPOSE:To obtain the high sensitivity and the high max. optical density and the low min. optical density of the subject material even in the case that the photosensitive material is processed with a developer having a relatively low pH by incorporating a specified alkinyl substd. heterocyclic ring quaternary ammonium salt in the photosensitive material. CONSTITUTION:At least one kind of a compd. shown by formula I is incorporated in the photosensitive material. In the formula, Z is a nonmetal atomic group necessary for forming a 6-membered heterocyclic ring nucleus contg. at least one of nitrogen atom, R<1> is an aliphatic group, R<2> is hydrogen atom or an aliphatic group, etc., at least one of of the groups R<1>, R<2> and Z is alkinyl group, Y is a pair ion for balancing an electric charge, (n) is a number necessary for balancing an electric charge. The additional amount of a nucleus forming agent shown by formula I in a silver halide emulsion is useful practically in an amount of a range of about 1X10<-8>-1X10<-2>mol, preferably about 1X10<-7>-1X10<-3>mol per 1mol of silver contd. in the silver halide emulsion. Thus, the sufficiently high max. optical density of the photosensitive material, without increasing the min. optical density of the material, is obtd. |
