Near-infrared absorbing fine particle dispersion liquid and method for producing the same

A near infrared absorbing fine particle dispersion liquid, comprising:

• a solvent of one or more kinds selected from petroleum-based solvents;
• near infrared absorbing fine particles of one or more kinds selected from 10 mass % more and 25 mass % or less of a composite tungsten oxide expressed by MxWyOz (M is an element of one or more kinds selected from H, He, alkali metal, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, TI, Si, Ge, Sn, Pb, Sb, B, F, P, S, Se, Br, Te, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os, Bi, and I, W is tungsten, O is oxygen, satisfying 0.001≤x/y≤1, and 2.2≤z/y≤3.0), and/or a tungsten oxide having a Magneli phase expressed by a general formula WyOz (W is tungsten, O is oxygen, satisfying 2.45≤z/y≤2.999);
• and
• a dispersant having a fatty acid in its structure, and soluble in the solvent,
• wherein a viscosity is 180 mPa·S or less,
• the solvent is one or more solvents selected from petroleum-based solvents having an aniline point of 60° C. or more and 95° C. or less and a boiling point of 50° C. or more and 350° C. or less, and
• the structure of the dispersant has a polylactone structure or a hydroxystearic acid chain.