The present invention discloses
a DNA fragment-containing invisible
infrared absorbing ink-jet ink and a preparation method thereof, wherein the
DNA fragment-containing invisible
infrared absorbing ink-jet ink comprises, by weight, 1-10% of an
infrared absorbing dye, 10-25% of deionized water, 1-15% of a moisturizing agent, 1-10% of a dispersant, 0.1-5% of a surfactant, 0.1-2% of a pH value adjusting agent, 0.1-2% of an
antiseptic sterilization agent, 0.1-2% of a
polymer-wrapped
DNA fragment, and the balance of a
solvent. The
DNA fragment-containing invisible infrared absorbing ink-jet ink has the following two anti-counterfeiting features that: 1, with the light color infrared absorbing dye, the ink is invisible under the
visible spectrum; and 2, the ink contains the DNA
chain segment. The DNA fragment-containing invisible infrared absorbing ink-jet ink is suitable for the invisible point code anti-counterfeiting, can further be printed on the
colored media so as to increase the anti-counterfeiting function on the base of no influence on the original color. In addition, the average particle size of the ink is less than 300 nm, the ink can not block the
nozzle, the ink-jet printing speed of more than 100 m / min can be met, the smooth printing can be maintained, and characteristics of no ink flying and rapid
drying provided.