| abstract |
An ink composition suitable for printing machine readable indicia on a substrate with an ink jet printing device is disclosed. The disclosed ink composition comprises water, a water soluble resin, a red fluorescent colorant material mixture comprising C.I. Basic yellow 40 dye, C.I. Basic Red 1 dye, and C.I. Basic Violet 11:1 dye, and a blue colorant material comprising C.I. Acid Blue 9. In the preferred embodiments of the ink composition, the dyes in the red fluorescent colorant material mixture are present in a weight ratio of approximately 1.12 to 1.36 to 1, respectively, and the weight ratio of the red fluorescent colorant material mixture to the blue colorant material is in the range of about 3.8 to 1 to about 46 to 1. |