An electromagnetic wave absorbing laminated transparent base material includes a plurality of sheets of transparent base materials; and an electromagnetic wave absorbing particle dispersoid including at least electromagnetic wave absorbing particles and a thermoplastic resin. The electromagnetic wave absorbing particles contain hexagonal tungsten bronze having oxygen deficiency. The tungsten bronze is expressed by a general formula: M.sub.xWO.sub.3−y (where one or more elements M include at least one or more species selected from among K, Rb, and Cs, 0.15≤x≤0.33, and 0<y≤0.46). Oxygen vacancy concentration N.sub.V in the electromagnetic wave absorbing particles is greater than or equal to 4.3×10.sup.14 cm.sup.−3 and less than or equal to 8.0×10.sup.21 cm.sup.−3. The electromagnetic wave absorbing particle dispersoid is arranged between the plurality of sheets of the transparent base materials.

A W.sub.18O.sub.49 peak is confirmed by X-ray diffraction analysis of a sputtering surface and a cross section orthogonal to the sputtering surface, a ratio I.sub.S(103)/I.sub.S(010) of a diffraction intensity I.sub.S(103) of a (103) plane to a diffraction intensity I.sub.S(010) of a (010) plane of W.sub.18O.sub.49 of the sputtering surface is 0.38 or less, a ratio I.sub.C(103)/I.sub.C(010) of a diffraction intensity I.sub.C(103) of the (103) plane to a diffraction intensity I.sub.C(010) of the (010) plane of W.sub.18O.sub.49 of the cross section is 0.55 or more, and an area ratio of W.sub.18O.sub.49 phase of a surface parallel to the sputtering surface is 37% or more.

A W.sub.18O.sub.49 peak is confirmed by X-ray diffraction analysis of a sputtering surface and a cross section orthogonal to the sputtering surface, a ratio I.sub.S(103)/I.sub.S(010) of a diffraction intensity I.sub.S(103) of a (103) plane to a diffraction intensity I.sub.S(010) of a (010) plane of W.sub.18O.sub.49 of the sputtering surface is 0.38 or less, a ratio I.sub.C(103)/I.sub.C(010) of a diffraction intensity I.sub.C(103) of the (103) plane to a diffraction intensity I.sub.C(010) of the (010) plane of W.sub.18O.sub.49 of the cross section is 0.55 or more, and an area ratio of W.sub.18O.sub.49 phase of a surface parallel to the sputtering surface is 37% or more.

Surface-treated infrared-absorbing fine particles with excellent moisture and heat resistance and excellent infrared-absorbing properties, surface-treated infrared absorbing fine particle powder containing the surface-treated infrared absorbing fine particles, an infrared absorbing fine particle dispersion liquid and an infrared absorbing fine particle dispersion body using the surface-treated infrared absorbing fine particles, and a method for producing them, wherein a surface of infrared absorbing particles is coated with a coating layer containing at least one selected from hydrolysis product of a metal chelate compound, polymer of hydrolysis product of a metal chelate compound, hydrolysis product of a metal cyclic oligomer compound, and polymer of hydrolysis product of a metal cyclic oligomer compound.

An infrared absorbing material fine particle dispersion liquid including infrared absorbing material fine particles and a solvent, the infrared absorbing material fine particles containing fine particles of composite tungsten oxide represented by a general formula MxWOy, the solvent containing water, wherein an absolute value of a zeta potential of the infrared absorbing material fine particle dispersion liquid is 5 mV or more and 100 mV or less.

An infrared absorbing material fine particle dispersion liquid including infrared absorbing material fine particles and a solvent, the infrared absorbing material fine particles containing fine particles of composite tungsten oxide represented by a general formula MxWOy, the solvent containing water, wherein an absolute value of a zeta potential of the infrared absorbing material fine particle dispersion liquid is 5 mV or more and 100 mV or less.

Electromagnetic wave absorbing particles are provided that include hexagonal tungsten bronze having oxygen deficiency, wherein the tungsten bronze is expressed by a general formula: M.sub.xWO.sub.3-y(where one or more elements M include at least one or more species selected from among K, Rb, and Cs, 0.15≤x≤0.33, and 0<y≤0.46), and wherein oxygen vacancy concentration N.sub.v in the electromagnetic wave absorbing particles is greater than or equal to 3×10.sup.14 cm.sup.−3 and less than or equal to 8.0×10.sup.21 cm.sup.−3.

Electromagnetic wave absorbing particles are provided that include hexagonal tungsten bronze having oxygen deficiency, wherein the tungsten bronze is expressed by a general formula: M.sub.xWO.sub.3-y(where one or more elements M include at least one or more species selected from among K, Rb, and Cs, 0.15≤x≤0.33, and 0<y≤0.46), and wherein oxygen vacancy concentration N.sub.v in the electromagnetic wave absorbing particles is greater than or equal to 3×10.sup.14 cm.sup.−3 and less than or equal to 8.0×10.sup.21 cm.sup.−3.

The present application proposes a method for detecting an okadaic acid based on a near-infrared photoelectric composite material, which includes the following steps: synthesizing NaYF.sub.4: Yb, Tm up-conversion nanoparticles (UCNPs) and a semiconductor material flower-like tungsten oxide (WO.sub.3) by a simple high-temperature solvothermal method; coupling the UCNPs with an okadaic acid monoclonal antibody through a classic amidation reaction to construct a competitive near-infrared photoelectrochemical immunosorbent assay (cNIR-PECIA) for okadaic acid detection. In addition, the present application employs a screen-printed carbon electrode (SPE) as the working electrode, and thus only requires a small amount of electrolytes, which is low-cost and maintenance-free.

The present application proposes a method for detecting an okadaic acid based on a near-infrared photoelectric composite material, which includes the following steps: synthesizing NaYF.sub.4: Yb, Tm up-conversion nanoparticles (UCNPs) and a semiconductor material flower-like tungsten oxide (WO.sub.3) by a simple high-temperature solvothermal method; coupling the UCNPs with an okadaic acid monoclonal antibody through a classic amidation reaction to construct a competitive near-infrared photoelectrochemical immunosorbent assay (cNIR-PECIA) for okadaic acid detection. In addition, the present application employs a screen-printed carbon electrode (SPE) as the working electrode, and thus only requires a small amount of electrolytes, which is low-cost and maintenance-free.