To provide an infrared-shielding material microparticles dispersion liquid, an infrared-shielding film, etc., each capable of inhibiting such a phenomenon as to discolor to bluish white on being irradiated with sunlight or the like.

The infrared-shielding material microparticles dispersion liquid is such that infrared-shielding material microparticles composed of tungsten oxide microparticles represented by general formula: WyOz and/or compound tungsten oxide microparticles represented by general formula: MxWyOz are dispersed in a solvent. This dispersion liquid is characterized by that the size distribution of the infrared-shielding material microparticles as determined by dynamic light-scattering method is such that the 50%-diameter is 10-30 nm, the 95%-diameter is 20-50 nm and the average diameter is 10-40 nm. The infrared-shielding film is characterized by being obtained by the following process: the surface of a base material is coated with such an infrared-shielding material microparticles dispersion liquid as the incorporated with a vehicle such as an ultraviolet-curable resin or thermosetting resin to form a coating film, from which the solvent is evaporated.

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