Patent ID: 6531272
Filing Date: 2003-03-11
Classification: G03C

Abstract:
A multicolor negative silver halide photographic element comprising a support bearing a cyan dye image-forming unit comprising at least one red-sensitive silver halide emulsion layer having associated therewith at least one cyan dye-forming coupler, a magenta dye image-forming unit comprising at least one green-sensitive silver halide emulsion layer having associated therewith at least one blue-sensitive silver halide emulsion layer having associated therewith at least one yellow dye-forming coupler, wherein said blue sensitive silver halide emulsion layer comprises, in combination, large tabular grains having an equivalent circular diameter of greater than 2 &mgr;m and a fragmentable electron donating compound, said combination of large tabular grains and fragmentable electron donating compound providing beneficial lowering of RMS granularity characteristics of said blue sensitive silver halide emulsion layer and improved MTF response in underlying layers, said fragmentable electron donating compound being of the formulaQâ€”Xâ€”Yâ€²Aâ€”(Xâ€”Yâ€²)k (A)kâ€”Xâ€”Yâ€²Zâ€”(Xâ€”Yâ€²)k or(Z)kâ€”Xâ€”Yâ€²wherein:Z is a light absorbing group; k is 1 or 2; A is a silver halide adsorptive group; and Q represents the atoms necessary to form a chromophore comprising an amidinium-ion, a carboxyl-ion or dipolar-amidic chromophoric system when conjugated with Xâ€”Yâ€²; X is an electron donor moiety, Yâ€² is a leaving proton H or a leaving group Y, with the proviso that if Yâ€² is H a base, &bgr;, is covalently linked directly or indirectly to X and wherein: 1) Xâ€”Yâ€² has an oxidation potential between 0 and about 1.4 V; and 2) the oxidized form of Xâ€”Yâ€² fragments to give the radical X. and the leaving fragment Yâ€²; and, optionally, 3) the radical X. has an oxidation potential <0.7V.