In color photographic materials according to a subtractive color process, development inhibitor-releasing couplers, so-called DIR couplers, have hitherto been used for the purpose of improving sharpness, graininess, color reproducibility, or the like photographic performance properties. The photographic actions of DIR couplers are described, e.g., in T. H. James (ed.), The Theory of Photographic Process, 4th Ed., pp. 610-611 & p. 344, MacMillan Publishing Co., New York (1977).
Known DIR couplers are roughly divided into a) those capable of releasing a development inhibitor or a precursor thereof, on coupling with an oxidation product of a developing agent at the time of development and, at the same time, forming a dye, and b) those capable of releasing a development inhibitor or a precursor thereof, on coupling with an oxidation product of a developing agent, but taking substantially no part in dye image formation.
Silver halide color photographic materials generally are comprised of a light-sensitive layer which develops a yellow color, a magenta color, or a cyan color. Where a DIR coupler of the former type is used in such a color photographic material, it is desirable, for the purpose of preventing color mixing, that the DIR coupler should form a dye of the same color as that formed by the dye image-forming coupler in the light-sensitive layer to which it is added. However, a DIR coupler which is capable of forming a magenta dye, while at the same time functioning sufficiently well as a DIR coupler, has not yet been discovered. Under the present situation, therefore, DIR couplers which form a yellow dye have been used in a green-sensitive layer. On the other hand, the DIR couplers of the latter type, which do not substantially participate in color image formation, can be utilized in light-sensitive layers irrespective of their color sensitivity without causing color mixing.
DIR couplers of the latter type, developed to date, include those described in U.S. Pat. No. 4,482,629, JP-A-63-37350 (the term "JP-A" as used herein means an "unexamined published Japanese patent application"), U.S. Pat. No. 5,026,628, EP 0443530, and EP 0514869. However, none of them can be said to satisfy all the requirements for DIR couplers of this type, i.e., causing no color mixing, producing sufficiently improved color reproducibility or sharpness, and having stability in light-sensitive material during storage. Thus, there still has been the need for further improvement.