High chloride (100) tabular grain emulsions containing large, thin tabular grains

摘要

A radiation-sensitive emulsion is disclosed in which at least 70 percent of total grain projected area is accounted for by tabular grains (a) having {100} major faces, (b) containing greater than 50 mole percent chloride, based on silver, (c) having a mean equivalent circular diameter in the range of from 2.0 to 5.0 mu m, and (d) exhibiting a mean thickness of 0.1 mu m or less. The emulsion is prepared by (a) precipitating up to 10 percent of the total silver forming the high chloride {100} tabular grains to create a first grain population under conditions that form a crystal lattice structure that favors the growth of high chloride {100} tabular grains, (b) thereafter rapidly introducing silver and halide ions to create a second grain population, and (c) growing the first grain population to create the high chloride {100} tabular grains by ripening out the second grain population.