METHOD OF PREPARING PIGMENTS Russian patent published in 1998 - IPC

FIELD: dyestuffs. SUBSTANCE: pigments are prepared by crushing filler with a part of dye taken in amount no more than 5% based on total amount of dye on vibrational centrifugal mill with 65-70% ball charge. After that, mixture is combined with remaining part of the same dye and resulting mixture is treated on vibrational centrifugal mill with 50-55% ball charge. EFFECT: increased fineness of pigment and improved its painting characteristics. 1 tbl