Patent ID: 9249329
Filing Date: 2016-02-02
CPC Classification: C08K,C09D

Claim Text:
1. An aqueous ink composition comprising: water; a co-solvent; and an aqueous submicron colorant wax dispersion comprising a plurality of colorant wax particles comprising a colorant core surrounded by a wax shell, wherein the colorant wax particles exhibit a particle size distribution of from about 150 nanometers to less than about 300 nanometers; wherein the aqueous submicron colorant wax dispersion is an aqueous submicron pigment wax dispersion containing at least 25 percent by weight of pigment based on the total weight of the pigment and wax in the pigmented wax dispersion; wherein the aqueous submicron colorant wax dispersion is prepared by (a) melting and mixing a dry colorant with at least one wax to form a colorant concentrate, wherein the colorant concentrate contains at least 25 percent by weight of colorant; (b) milling the colorant concentrate of step (a) to form a milled colorant concentrate; (c) combining the milled colorant concentrate of (b) with water and dispersing to form the colorant wax dispersion; wherein the melting and mixing of step (a) and the milling of step (b) is done in an immersion media mill or a horizontal mill; and wherein the combining of step (c) is done using a piston homogenizer.