Patent ID: 7534291

Claim:
An ink composition comprising a colorant, a solvent, a surfactant, and a defoaming agent, wherein the defoaming agent has a structure as in Formula (I), R 1 —X—(CH 2 CH 2 O) m -(CHCH 3 CH 2 O) n -R 2 (I) in which, X is selected from the group consisting of COO, S, R 3 —N and R 4 (R 5 )—C; R 1 , R 2 , R 3 , R 4 , and R 5 are each independently selected from the group consisting of a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group and a substituted or unsubstituted aralkyl group; m is an integer from 0 to 100; and n is a natural number from 1 to 100.