| abstract |
Colored organic solid particles of potential value as pigments are partially milled to an extent less than that required to develop full pigmentary strength by size reduction and further conditioned concurrently with a flushing step. The organic pigment particles are transferred from an aqueous dispersion to an organic hydrophobic vehicle in the presence of an organic breaching agent. The resulting flushed pigmented vehicle has pigmentary strength at least equal to that obtained by fully conditioning the crude particles without the breaching treatment. The conditioned pigments need not be recovered as a dry powdered product. The process is valuable in the manufacture of flushed phthalocyanines, quinacridones, etc., with substantial improvement in equipment utilization in milling. The flushed pigmented vehicles are useful in manufacture of paints, varnishes, lacquers, inks, color concentrates, and formulations for mass coloration of plastics. |