| abstract |
An agglomerated pigment comprises (1) an organicnpigment compound, (2) either a sulfonated organic pigmentncompound obtained by incorporating at least one sulfonicngroup into the organic pigment compound or a sulfonatednorganic pigment derivative obtained by incorporating at leastnone sulfonic group into a derivative of the organic pigmentncompound, (3) univalent inorganic counter ions bonded tonsulfonic groups of component (2), and (4) bivalent or higherninorganic counter ions which are bonded to sulfonic groups ofncomponent (2) and each has an at least univalent positivencharge, the surface of the agglomerated organic pigment as anwhole being positively charged. An aqueous pigmentndispersion and a water-based ink composition both havingnexcellent storage stability, an agglomerated pigment for usenas a raw material for the dispersion, and a process fornproducing the pigment are provided. |