Process for digestion of silver halide emulsions - replacing sulphur cpds. with seleno-organic cpd. to enhance sensitivity while maintaining low fogging and grain

摘要

A process for digestion of silver halide emulsions at 35-65[deg]C and pH 2-10 utilises 10-9 to 10-3 moles per mole of silver halide of formula (I); Y = C=X, C-Z or SO2; X = O or NR2; Z = halogen; n = 0, or 1 in case of Y = C-Z; R1 = H or substit. or forming fused ring with X; R2 = H or substit.; and Q = atoms to form a 5- or 6-membered ring.