Silver bromide emulsions of narrow grain size distribution and processes for their preparation

摘要

Radiation-sensitive emulsions are disclosed containing tabular silver bromide grains bounded by two substantially parallel square or rectangular crystal faces and having an average aspect ratio of at least 8.5:1. The tabular grains preferably exhibit a coefficient of variation of less than 30. The tabular grains are formed by providing cubic seed grains having an edge length of less than 0.15 micron and ripening the seed grains at a pAg in the range of from 5.0 to 8.0 in the substantial absence of non-halide silver ion complexing agents.