| 摘要 |
PURPOSE:To form a fog inhibitor capable of preventing fog due to overdevelopment and extremely small in loss of photosensitivity by incorporating a specified compd. in a silver halide emulsion layer and/or a colloidal layer having water permeability relation between this layer and said emulsion layer. CONSTITUTION:The fog inhibitor to be added is a thioether type fog inhibitor precursor, sufficiently stable in a weak acid medium, extremely effective against over- development fogging, and further, extremely small in deterioration of sensitivity, and it is represented by formula (I) and (II) in which A is the heterocyclic group of the mercapto fog inhibitor. As the inhibitor, any compd. having a fog preventive effect may be used, and compds. each having an N-cong. 5- or 6-membered hetero ring having an S atom combined with the C atom adjacent to the N atom of said ring are especially preferable, and such a ring can be typified by tetrazole, etc., rings. |
