Abstract

Ink compositions that are particularly suitable for, but are not limited to, color, thermal ink-jet printing on various print media are described. The ink compositions of the present invention provide superior decap performance and decreased image drying time without sacrificing other, important ink composition characteristics. One embodiment of an ink composition according to the present invention comprises, by weight, from about 0.5 to about 20 percent water-soluble dye, and from about 5 to about 30 percent of an organic solvent comprising a branched, lower alkyl compound having terminal hydroxyl groups, with the balance being mostly water. Currently, the best results appear to be achieved when the organic solvent is a 1,3-propanediol having a lower alkyl group at the two position, such as 2-methyl-1,3-propanediol, or a mixture of a 1,3-propanediol having a lower alkyl group at the two position and a butanediol, such as 1,4-butanediol. Other components commonly found in ink-jet ink compositions, such as biocides, surfactants and pH buffers, may be added to the ink compositions of the present invention.