Disclosed is an ink composition which comprises (a) water, (b) a colorant, (c) a fluorinated material selected from: (1) those of the formula �(F.sub.2n+1 C.sub.n CH.sub.2 S).sub.2 (CH.sub.3)C--CH.sub.2 CH.sub.2 COO.sup.- !�B.sup.+ !, wherein n is an integer of from about 8 to about 20 and B is a cation, (2) those of the formula �(F.sub.3 C(F.sub.2 C).sub.n CH.dbd.CHCH.sub.2 OCH(OH)CH.sub.2).sub.2 NCH.sub.2 COO.sup.- !�X.sup.+ !, wherein X is a cation and n is an integer of from about 3 to about 20, and (3) mixtures thereof, and (d) a monomeric compound having at least two carboxylic acid functional groups. Also disclosed is a process for preparing said ink composition which comprises (i) admixing the ink ingredients, and (ii) subjecting the mixture thus formed to ultrasonification, thereby reducing the average particle diameter of liposomes of the fluorinated material in the ink. Further disclosed is a process which entails (i) incorporating into an ink jet printing apparatus the aforementioned ink composition, and (ii) causing droplets of the ink composition to be ejected in an imagewise pattern onto a substrate. In a preferred embodiment, the printing apparatus employs a thermal ink jet process wherein the ink in the nozzles is selectively heated in an imagewise pattern, thereby causing droplets of the ink to be ejected in imagewise pattern.