Patent ID: 6440207
Filing Date: 2002-08-27
Classification: C08G,C09B,C09D

Abstract:
A process for preparing a dispersible organic pigment composition comprising(a) wet-milling a mixture comprising (1) one or more organic pigments, (2) at least about 1% by weight, relative to the organic pigment, of one or more aromatic polyalkylene oxide dispersants, (3) a positive amount of up to about 10 parts by weight, relative to the organic pigment, of a milling liquid in which the organic pigment is substantially insoluble, (4) 0 to about 50% by weight, relative to the organic pigment, of one or more milling additives other than dispersant (2), and (5) 0 to about 20% by weight, relative to the organic pigment, of one or more surface treatment additives; (b) optionally, adding to the milled pigment (6) one or more liquids in which the organic pigment is substantially insoluble in amounts such that the total solids content is not reduced below about 10%, and (7) one or more multivalent metal salts and/or one or more quaternary ammonium salt; and (c) isolating and drying the milled organic pigment.