PROCESS OF FORMING YELLOW PHOTOGRAPHIC IMAGES

摘要

This invention discloses a novel process for forming a dye image which comprises developing an image-exposed silver halide photographic emulsion layer by an aromatic primary amine colour developing agent in the presence of an (aromatic acyl) acetoamide compound which is substituted in the d-position by a diacylamino group. This latter compound is represented by the general formula (I) wherein R1 is an aryl group, R2 is an aryl group or a heterocyclic group, and Z is the non-metallic atom or atoms necessary to form, together with the moiety in the formula, a 4-, 5- or 6- membered substituted or unsubstituted ring. A photographic element containing this compound is also disclosed. These novel yellow-forming couplers are 2- equivalent yellow couplers and require only two moles of exposed silver halide to form one mol of methine dye. These couplers are suitable for colour photography using the colour subtraction process and reduce the content of silver halide incorporated into the emulsion thereby improving the sharpness of the image obtained.