Near-infrared shielding ultrafine particle dispersion body, near-infrared shielding intermediate film, near-infrared shielding laminated structure, and method for producing near-infrared shielding ultrafine particle dispersion body

A near-infrared shielding ultrafine particle dispersion body in which ultra-fine particles having near-infrared shielding properties are dispersed in a solid medium,

• wherein the ultrafine particles are composite tungsten oxide ultrafine particles represented by a general formula MxWyOz in which M is one or more elements selected from the group consisting of H, He, Li, Na, Rb, Cs, alkaline earth metal, rare earth element, Mg, Zr, Cr, Mn, Fe, Ru, Co, Rh, Jr, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga, In, Tl, 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, x, y, and z satisfy 0.001≤x/y≤1, 2.0<z/y≤3.0, and have an XRD peak top intensity ratio value of 0.13 or more based on an XRD peak intensity ratio value of 1 on plane (220) of a silicon powder standard sample,
• a dispersed particle size of the composite tungsten oxide ultrafine particles is 10 nm or more and 200 nm or less,
• a crystallite size of the composite tungsten oxide ultrafine particles is 10 nm or more and 200 nm or less,
• each of the composite tungsten oxide ultrafine particles is made of a single crystal in which a volume ratio of an amorphous phase in the composite tungsten oxide ultrafine particles is less than 50%,
• the solid medium contains a resin binder and a weather resistance improver,
• the weather resistance improver includes at least one selected from the group consisting of a benzotriazole-based UV absorber, a triazine-based UV absorber, and a benzophenone-based UV absorber, and
• a content of a volatile component contained in the composite tungsten oxide ultrafine particles is 1.3 mass % or more and 1.6 mass % or less.