摘要 |
A process for incorporating dopants in a silver halide emulsion is described comprising precipitating silver halide emulsion grains in a reaction vessel, wherein at least one gallium dopant, at least one Group 8 metal dopant, and at least one selenium dopant are introduced into the reaction vessel during precipitation of the silver halide grains; where the gallium dopant is introduced in the form of a gallium halide coordination complex of the formula (I):wherein R represents a lower alkyl group of from 1-3 carbon atoms; X is Cl, Br, or I; and x is from 1-3, y is from 1-3, and x+y=4; and the Group 8 metal dopant satisfies the formula (II):wherein n is -2, -3 or -4; M is a Fe<+2>, Ru<+2>, or Os<+2 >ion; and L6 represents bridging ligands which can be independently selected, provided that at least four of the ligands are anionic ligands, and at least one of the ligands is a cyano ligand or a ligand more electronegative than a cyano ligand. In another embodiment, this invention is directed towards silver halide emulsions formed by such process. In a still further aspect, this invention is directed towards a photographic element comprised of a support, and a silver halide emulsion layer coated on the support comprised of an emulsion obtained by the process of the invention.
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