METHOD OF MANUFACTURING SILVER BROMIDE/IODIDE PHOTOGRAPHIC EMULSIONS Russian patent published in 1997 - IPC

FIELD: chemical-photographic industry. SUBSTANCE: emulsions are manufactured by way of conducting controlled two-jet emulsification with simultaneously introducing, into solution 1 containing gelatin, ammonia, and water, solution 2 containing silver nitrate and water and solution 3 containing potassium bromide and iodide mixture and water at pH 8.4-9.5 and constant pBr value (2.7-3.7). Before emulsification is commenced, solution 1 or emulsion in the emulsifying process is supplemented with (1-4) x 10^-4 mol per 1 mol of silver in solution 2 of surfactant compound - sodium sulfosuccinic acid diester with general formula R′OOCH₂-CHCOOR²-SO₃Na where and w =1 or 2. EFFECT: increased resolution capability of monodisperse emulsions of one dimension class by 1-3 line groups of absolute contrast measure with sensitometric characteristics retained. 1 tbl