Patent ID: 7034065

Claim:
An ink jet ink composition comprising water, a dispersed pigment, a humectant and a hyperbranched polymer having end groups consisting essentially of hydrophilic moieties, said hyperbranched polymer having the following formula: HB—X g wherein: HB is a hyperbranched polymer core; X is a hydrophilic end group; and g is an integer of at least 2, wherein said hyperbranched polymer is a chain polymerized residue of a monomer of the formula M 1 n —R 1 —M 2 m wherein (i) R 1 is a substituted or non-substituted straight, cyclic or branched alkyl, alkenyl, or aryl moiety or hetero atom containing substituted or non-substituted straight, cyclic or branched alkyl, alkenyl, or aryl moiety; (ii), M 1 and M 2 are reactive groups that react independently of each other in which M 1 is a polymerization group and M 2 is a precursor of a moiety M 2 * which initiates the polymerization of M 1 as a result of being activated by any source; and (iii), n and m are integers of at least 1.