Heat ray shielding fine particles, heat ray shielding fine particle dispersion liquid, coating liquid for heat ray shielding layer, and heat ray shielding layer, heat ray shielding resin film, heat ray shielding dispersion body using them

1. Heat ray shielding fine particles containing calcium lanthanum boride fine particles represented by a general formula Ca x La 1-x B m ,

wherein a value of x in the general formula is 0.001≤x≤0.800, and a value of m is 5.0≤m<6.3,

an average dispersed particle size of the calcium lanthanum boride fine particles is 1 nm or more and 800 nm or less,

a shape of each fine particle of the calcium lanthanum boride fine particles satisfies at least one of the following:

1) when scattering intensity of the calcium lanthanum boride fine particles diluted and dispersed in a solvent is measured using small-angle X-ray scattering, value Ve of a slope of a straight line is −3.8≤Ve≤−1.5, which is obtained by double-logarithmic plotting of a relationship between scattering vector q=4π sin θ/λ and scattering intensity I(q),

2) the particle shape is a flat cylindrical (wherein a diameter of the bottom circle is d and a height of the cylinder is h) shape, or a flat spheroidal (wherein a length of the long axis is d and a length of the short axis is h) shape, with a value of aspect ratio d/h being 1.5≤d/h≤20.

2. The heat ray shielding fine particles according to claim 1 , wherein a value of x in the general formula is 0.100≤x≤0.625, and a value of m is 5.0≤m<6.3.

3. The heat ray shielding fine particles containing the calcium lanthanum boride fine particles of claim 1 , which are two or more kinds of calcium lanthanum boride fine particles having different values of x in the above general formula.

4. A heat ray shielding fine particle dispersion liquid, which is a dispersion liquid containing the heat ray shielding particles of claim 1 dispersed in a liquid medium,

wherein the liquid medium is one or more selected from water, organic solvents, fats and oils, liquid resins, and liquid plasticizers for plastics.

5. The heat ray shielding particle dispersion liquid according to claim 4 , wherein the heat ray shielding particles are contained in an amount of 0.02 mass % or more and 20 mass % or less.

6. A coating liquid for a heat ray shielding layer, wherein a binder containing one or more selected from UV curable resin, room temperature curable resin, thermoplastic resin, or partial hydrolysis polymer of alkoxide is added to the heat ray shielding fine particle dispersion liquid according to claim 4 , and

a content of the heat ray shielding particles is 0.8 mass % or more and 10.0 mass % or less.

7. A heat ray shielding layer, which is formed by applying the coating liquid for a heat ray shielding layer of claim 6 on one side or both sides of a base material.

8. A heat ray shielding resin film in which the heat ray shielding layer according to claim 7 is formed on one side or both sides of a base material,

wherein the base material is a resin film, and resin of the resin film is one or more selected from polycarbonate resin, poly (meth) acrylic ester resin, saturated polyester resin, and cyclic olefin resin.

9. The heat ray shielding resin film according to claim 8 , wherein an adhesive layer for adhesion is provided on at least one side of the resin film.

10. The heat ray shielding resin film according to claim 9 , wherein the adhesive layer for adhesion contains the heat ray shielding particles.

11. The heat ray shielding resin film according to claim 8 , wherein a surface resistance value of the heat ray shielding layer or the adhesive layer for adhesion containing the heat ray shielding particles is 10 6 Ω/□ or more.

12. A heat ray shielding fine particle dispersion body wherein the heat ray shielding fine particles according to claim 1 are dispersed in a thermoplastic resin or a UV curable resin.

13. The heat ray shielding fine particle dispersion body according to claim 12 ,

wherein the thermoplastic resin is one of the resins selected from a group of polyethylene terephthalate resin, polycarbonate resin, acrylic resin, styrene resin, polyamide resin, polyethylene resin, vinyl chloride resin, olefin resin, epoxy resin, polyimide resin, fluorine resin, ethylene/vinyl acetate copolymer, and polyvinyl acetal resin,

or the mixture of two or more resins selected from the above resin group,

or a copolymer of two or more resins selected from the above resin group.

14. The heat ray shielding fine particle dispersion body according to claim 12 , which contains 0.001 mass % or more and 80.0 mass % or less of the heat ray shielding fine particles.

15. The heat ray shielding fine particle dispersion body according to claim 12 , wherein the heat ray shielding fine particle dispersion body has a sheet shape, a board shape or a film shape.

16. The heat ray shielding fine particle dispersion body according to claim 12 , wherein a content of the heat ray shielding particles is 0.01 g/m 2 or more and 0.5 g/m 2 or less per unit projected area contained in the heat ray shielding particle dispersion body.