Preparation of pigmentary form of quinacridone pigments

A process of preparing pigmentary grade quinacridone from crude quinacridone consisting essentially of a quinacridone or mixture of quinacridones of the formula ##STR5## and mixtures thereof, with 0 to 75 weight percent of unsubstituted quinacridone and 0 to 15 wt. % of a quinacridone of the formula ##STR6## where R.sup.1, and R.sup.2 are fluorine, chlorine, bromine, methyl or methoxy;

• R.sup.7, R.sup.9, and R.sup.10 are hydrogen or chlorine;
• R.sup.3, R.sup.4, R.sup.5, and R.sup.6 are hydrogen, fluorine, chlorine, bromine, methyl, or methoxy;
• and R.sup.8 is hydrogen, chlorine, bromine, nitro, alkyl groups of 1 to 5 carbon atoms, alkoxy groups of 1 or 2 carbon atoms or benzoylamino, and m is an integer of from 1 to 4 by converting the crude quinacridone to a low crystallinity aggregated form, followed by milling the low crystallinity quinacridone in a water miscible organic liquid which is effective in improving the crystallinity of quinacridone particles containing up to an equal amount of water present in an amount sufficient to give a fluid slurry and recovering a pigmentary product.