| 摘要 |
Granulates of dyestuffs or optical brighteners with a particle size of >=1 mm are obtd. by mixing the dyestuff or brightener with urea, water and a water-immiscible org. solvent, with heating, distilling off the water azeotropically and sepg. the deposited granulate from the the emulsion and drying it. Used for the prepn. of non-dusting granulates of pref. water-sol. dyestuffs or brighteners of the acid, acid reactive and cationic type, partic. those contg. >=1 sulphonic acid group. The granulates have increased stability wrt known granulates or powderS. |
