Patent ID: 8318833

Claim:
A pigment suspension, comprising: a) an aqueous liquid vehicle; and b) a polymer-encapsulated pigment suspended in the liquid vehicle, said polymer-encapsulated pigment including: i) a pigment core; ii) a passivation layer deposited on a surface of the pigment core that is formed from a passivation component including an amphiphilic polymer selected from the group consisting of polyvinylpyrrolidone, polyethylene glycol, vinylpyrrolidone/vinyl acetate copolymers, poly(styrenesulfonate), poly(diallyldimethylammonium chloride), poly(ethylene-co-methacrylic acid), poly(ethylene-co-maleic acid), poly(styrene-co-maleic acid) and poly(vinylimidazole), block and random copolymers of vinylpyrrolidone, and mixtures thereof; and iii) a polymer-encapsulation layer attached to or deposited on the passivation layer, wherein the concentration range for the passivation component is from 2 to 3 parts for every 10 parts of pigment core by weight.