DE2459895

1477379 Spray drying of base dyestuffs CIBA-GEIGY AG 19 Dec 1974 [20 Dec 1973] 55003/74 Heading C4P A process for the production of spray dried, low melting basic dyestuffs comprises spray drying by means of a cooled atomizing organ of an aqueous suspension of a crystalline, lowmelting, basic dyestuff having a particle size of 1-100 Á and containing at least 5%, relative to the amount of dry dyestuff, of an additive which stabilizes the suspension and maintains the crystalline modification. A disc atomizer or spray nozzle cooled to 25-60‹ C. may be used. The dyestuffs (azo or others) have a decomposition point of below 200‹ C., especially 30- 150‹ C. The additives are water-soluble salts of inorganic acids, especially sodium sulphate or KCl, or a mixture thereof.