Patent ID: 8721782

Claim:
An ink formulation comprising (a) an ink base, (b) a poly(hydroxystearic acid) derived dispersant and (c) a carbon black pigment, wherein said dispersant is of a general formula III: in which R is Y is R 2 SO 3 —, CF 3 SO 3 —, Cl−, Br—, I—, or R 2 CO 3 —, R 1 is —CH 2 , or —CH(R 2 ); R 2 is independently H, —CH 3 , —C 2 H 5 , —C 3 H 7 , —C 4 H 9 , —C 5 H 11 , —C 6 H 13 , —C 7 H 15 , —C 8 H 17 , —C 9 H 19 , —C 11 H 21 , —C 12 H 23 , —C 13 H 25 , —C 14 H 27 , —C 15 H 29 , —C 16 H 31 , —C 17 H 33 or —C 18 H 37 ; n is an integer between 1 and 5; and m is an integer between 1 and 5.