HEAT STABLE IR SCANNABLE WATERFAST INKS FOR INK JET PRINTERS

摘要

An ink jet ink composition comprises a liquid vehicle, a primary dye, a sulfur black dye, a polymer, and at least one water soluble organic solvent for enhancement of waterfastness. The ink preferably comprises 1% ethoxylated polyethyleneimine to which is added 2% N-methyl-pyrrolidone, to increase the waterfastness of the ink to a level greater than 90%. The presence of at least 4% of a 10% liquid sulfur black dye provides heat stability to the ink. An additional approximately 6% to 8% of the 10% liquid sulfur black dye can be provided to make the ink both heat stable and infrared scannable.