abstract |
Dispersions of organic pigments are produced by adding a surfactant to an aqueous slurry of an organic pigment followed by subjecting the slurry to ultrasonic radiation. The surfactant utilized is one or more of the surfactants selected from the group consisting of: various specific acidic or quaternary salts of alkyl substituted propanediamines, and derivatives thereof, as well as a poly(ethyleneoxide) ether of an 18 carbon alcohol having 9 units of ethylene oxide thereon. |