abstract |
By use of composite tungsten oxide particles having a high heat ray-shielding effect while mainly composed of polyvinyl acetal resin, a heat ray-shielding particle is provided, having an excellent optical performance and a high weather resistance, which includes a composite tungsten oxide particle expressed by a general formula M y WO z (wherein M is one or more kinds of element selected from Cs, Rb, K, Tl, In, Ba, Li, Ca, Sr, Fe, Sn, Al, and Cu, satisfying 0.1 ¤ y ¤0. 5, 2.2 ¤ z ¤ 3.0) and having a hexagonal crystal structure; and at least one of a dispersant having an acrylic backbone, having an amino group as a functional group, and having a thermal decomposition temperature of 200°C or more, and a dispersant having an acrylic backbone, having a hydroxyl group or a carboxyl group as a functional group, and having a thermal decomposition temperature of 200°C or more, wherein a content of an organic solvent having a boiling point of 120°C or less is 5 mass% or less. |