Solid particle dispersions for imaging systems.

摘要

A process for preparing a stable, solid particle dispersion of a substantially water-insoluble compound useful in imaging, comprises the steps of: (a) forming a coarse aqueous slurry of solid particles of said compound and a hydrophobic, water-soluble or water-dispersible polymer in an amount of 0.1 to 100% by weight based on the weight of said compound; and (b) milling said slurry for time sufficient to provide particles of the desired average particle size; wherein the polymer is an uncharged or weakly anionically charged water-soluble or water-dispersible homopolymer or copolymer in which at least 10 mole % of the repeat units contain an uncharged pendant group that terminates in (a) a CH3 unit, (b) a ring containing at least two contiguous CH2 units, or (c) an aromatic group. The resulting dispersion has dispersed solid particles of said compound having the desired small particle size and is stable toward particle agglomeration, particle growth and needle growth.