Preparation of agx emulsions in the presence of a thioether having amino and carboxylic groups

Abstract From the Canadian patent

In the preparation of silver halide emulsions silver halide grain-growth is accelerated by the addition to the precipitation medium during or before silver halide precipitation of a compound of the formula wherein :, n is an integer from 1 to 5 R1 is C1-C5 alkyl or substituted alkyl R2 is hydrogen or C1-C5 alkyl or substituted alkyl or a, carboxylic acyl group, R3 is hydrogen or C1-C5 alkyl or substituted alkyl and, R is hydrogen or C1-C5 alkyl or substituted alkyl group aryl or substituted aryl or a salt-forming cation.