Silver halide photographic element containing fogged emulsions for accelerated development

摘要

This invention relates to a negative silver halide photographic element comprising a support and a silver halide imaging layer containing a light sensitive silver halide imaging emulsion, said silver halide imaging layer further comprising a separately precipitated non-imaging intentionally fogged fine grain emulsion and an electron transfer agent releasing compound represented by formula (I):$\mathop{\mathrm{image}} \[ {\text{CAR}}^{\text{1}}{\text{-(L)}}_{\text{n}}\text{-ETA} \]$ wherein:CAR¹ is a carrier moiety which is capable of releasing ―(L)n-ETA on reaction with oxidized developing agent;L is a divalent linking group, n is 0, 1 or 2; andETA is a releasable electron transfer agent, and (optionally) a development accelerator releasing compound represented by the formula (II):$\mathop{\mathrm{image}} \[ {\text{CAR}}^{\text{2}}{\text{-(SAM)-NX}}^{\text{1}}{\text{-NX}}^{\text{2}}{\text{X}}^{\text{3}} \]$ wherein:CAR² is a carrier moiety which is capable of releasing -(SAM)-NX¹-NX²X³ on reaction with oxidized developing agent;SAM is a silver absorbable moiety attached to the carrier moiety and is released on reaction with oxidized development agent; and- NX¹-NX²X³ is a hydrazine group wherein X¹, X² and X³ are individually hydrogen or a substituent chosen from alkyl, aryl, carbonyl, or sulfonyl groups with the proviso that at least one of X¹, X² and X³ is hydrogen.