NEAR-INFRARED RAY ABSORBING MICROPARTICLE DISPERSION SOLUTION, PRODUCTION METHOD THEREOF, COUNTERFEIT-PREVENTING INK COMPOSITION USING SAID NEAR-INFRARED RAY ABSORBING MICROPARTICLE DISPERSION SOLUTION, AND ANTI-COUNTERFEIT PRINTED MATTER USING SAID NEAR-INFRARED RAY ABSORBING MICROPARTICLES

摘要

The purpose of the present invention is to provide a near-infrared ray absorbing microparticle dispersion solution which has infrared region absorption capacity, has clear contrast and can be applied in offset printing; a method of producing the near-infrared ray absorbing microparticle dispersion solution; a counterfeit-preventing ink composition using said near-infrared ray absorbing microparticle dispersion solution; and anti-counterfeit printed matter using said near-infrared ray absorbing microparticles. A near-infrared ray absorbing microparticle dispersion solution is provided which contains one or more solvents selected from petroleum-based solvents, 2-25 mass% of one or more types of near-infrared ray absorbing microparticles selected from hexaboride particles represented by the general formula XBa, and a dispersant which is soluble in the solvent and includes a fatty acid in the structure; also provided is a counterfeit-preventing ink composition which contains the near-infrared ray absorbing microparticle dispersion solution. Further, by means of printed matter containing the near-infrared ray absorbing microparticles, anti-counterfeit printed matter is provided which has an excellent anti-counterfeiting effect.