Patent ID: 11248133

Abstract:
A near infrared absorbing-fine-particle dispersion liquid having absorption in a near infrared region, having clear contrast, and being applicable to offset printing; a method for producing the same; an anti-counterfeit ink composition using the near infrared absorbing-fine-particle dispersion liquid; and anti-counterfeit printed matter using the near infrared absorbing-fine-particles. The near infrared absorbing-fine-particle dispersion liquid contains a solvent of one or more from vegetable oils or vegetable oil-derived compounds; near infrared absorbing-fine-particles of 2 mass % or more and 25 mass % or less, selected from one or more of hexaboride fine-particles expressed by formula XBa (where X is one or more kinds of specified elements, and 4.0≤a≤6.2); and a dispersant soluble in solvent and having a fatty acid in its structure, where the viscosity is 180 mPa·s or less. The anti-counterfeit printed matter is excellent in anti-counterfeit effect due to the near infrared absorbing-fine-particles.