Electroconductive particle, visible light transmitting particle-dispersed electrical conductor and manufacturing method thereof, transparent electroconductive thin film and manufacturing method thereof, transparent electroconductive article that uses the same, and infrared-shielding article

An infrared-shielding nanoparticle dispersion obtained by dispersing infrared-shielding nanoparticles in a medium, wherein

• said infrared-shielding nanoparticles include composite oxide nanoparticles expressed by the general formula MEAGW(1-G)OJ;
• the M is one or more elements selected from Cs, Rb, K, Li, Ba, Ca, Sr, Fe, In, and Sn;
• the A is one or more elements selected from Mo, Nb, Ta, Mn, V, Re, Pt, Pd, and Ti;
• the W is tungsten;
• the O is oxygen;
• 0.2≦E≦0.5, 0<G<1, and 2 ≦J≦3 are satisfied;
• and
• the composite oxide expressed by the general formula MEAGW(1-G)OJ has a hexagonal crystal structure.

A method for manufacturing infrared-shielding nanoparticles composed of composite oxide nanoparticles expressed by the general formula MEAGW(1-G)OJ wherein the M is one or more elements selected from Cs, Rb, K, Li, Ba, Ca, Sr, Fe, In, and Sn;

• the A is one or more elements selected from Mo, Nb, Ta, Mn, V, Re, Pt, Pd, and Ti;
• the W is tungsten;
• the O is oxygen;
• 0.2≦E≦0.5, 0<G<1, and 2 ≦J≦3 are satisfied;
• and the composite oxide expressed by the general formula MEAGW(1-G)OJ has a hexagonal crystal structure, the method comprising
• heat treating a starting material of the composite oxide nanoparticles in an atmosphere of a reducing gas and/or an inert gas at 250° C. or greater to manufacture the composite oxide nanoparticles.

A transparent electroconductive film composed of a composite oxide expressed by the general formula MEAGW(1-G)OJ, wherein

• the M is one or more elements selected from Cs, Rb, K, Li, Ba, Ca, Sr, Fe, In, and Sn;
• the A is one or more elements selected from Mo, Nb, Ta, Mn, V, Re, Pt, Pd, and Ti;
• the W is tungsten;
• the O is oxygen;
• 0.2 ≦E≦0.5, 0<G<1, and 2 ≦J≦3 are satisfied;
• maximum transmittance of the film in the region of 400 nm or greater to 780 nm or less ranges from 10% or greater to less than 92%;
• surface resistance of the film is 1.0×1010 Ω/square or less;
• the composite oxide expressed by the general formula MEAGW1-G)OJ has a hexagonal crystal structure;
• and
• the film is formed directly on a non-electroconductive substrate.