Process for rapid manufacture of large tabular grains with novel size distribution

摘要

An improvement in tabular grain manufacture is provided wherein large tabular grains can be prepared in less time and with a narrower size distribution than available in the art. The improved process includes the steps of: a) forming a nucleation solution by adding aqueous soluble silver salt to a vessel containing 0.08 to 0.25 molar aqueous soluble halide salt in an aqueous medium; b) adding a solution of ammoniacal base to said nucleation solution when 0.30 to 9.0% of said soluble silver salt has been added; c) optionally ripening said nucleation solution for up to 60 minutes; d) adding said soluble silver salt to said nucleation solution preferrably at an increasing rate to obtain growth pBr of 1.3 to 2.3; e) adding said soluble silver salt and said soluble halide salt to grow said tabular grains.