Patent ID: 7666924

Claim:
A water dispersion for ink-jet printing comprising: a polymeric dispersant, water, and a colorant, wherein the polymeric dispersant comprises a vinyl polymer, the water dispersion is a dispersion comprising vinyl polymer particles comprising the colorant, the vinyl polymer particles being formed at least from the vinyl polymer and the colorant, and the vinyl polymer has a constitutional unit represented by the following formula 1: wherein R 1 is a hydrogen atom or a methyl group, R 2 and R 4 are the same and are an alkylene group having from 2 to 3 carbon atoms, M 1 and M 2 may be the same or different and are each independently a hydrogen atom or a cation, R 3 is an alkylene group having 4 carbon atoms, k and m are zero, and L is a number from 2 to 20.