Aqueous dispersion liquid and coating material, film, and product using the same
In one embodiment, an aqueous dispersion liquid contains at least one particles selected from tungsten oxide particles and tungsten oxide composite particles. A mean primary particle diameter (D50) of the particles is in the range of 1 nm to 400 nm. In the aqueous dispersion liquid, concentration of the particles is in the range of 0.1 mass % to 40 mass %, and pH is in the range of 1.5 to 6.5. The aqueous dispersion liquid excels in dispersibility of particles and capable of maintaining good liquidity for a long period.
1. A method for producing a film, comprising:
applying an aqueous dispersion liquid or a coating material comprising the aqueous dispersion liquid and at least one binder component selected from an inorganic binder and an organic binder on a substrate to form an applied film of the aqueous dispersion liquid or the coating material; and
drying the applied film to produce the film,
wherein the aqueous dispersion liquid comprises particles selected from tungsten oxide particles and tungsten oxide composite particles and a dispersion medium including water,
wherein a mean primary particle diameter (D50) of the particles is in a range of 1 nm to 400 nm, a concentration of the particles in the aqueous dispersion liquid is in a range of 0.1 mass % to 40 mass %, and pH of the aqueous dispersion liquid is in a range of 1.5 to 6.5, and
wherein the tungsten oxide composite contains at least one metal element selected from transition metal elements and aluminum, or a compound including at least one metal element selected from transition metal elements and aluminum, in a range of 0.001 mass % to 50 mass % as an amount of the metal element, balanced by tungsten oxide.
2. The producing method according to claim 1 ,
wherein the dispersion medium contains alcohol in a range of 20 mass % or less.
3. The producing method according to claim 1 ,
wherein the coating material contains the binder component in a range of 5 mass % to 95 mass %.
4. The producing method according to claim 1 ,
wherein the concentration of the particles in the aqueous dispersion liquid is in a range of 1.0 mass % to 20 mass %, and pH of the aqueous dispersion liquid is in a range of 2.5 to 5.5.
5. The producing method according to claim 1 ,
wherein a D90 diameter of a particle size distribution of the particles in the aqueous dispersion liquid is in a range of 0.01 μm to 10 μm.
6. The producing method according to claim 1 ,
wherein the metal element is at least one element selected from titanium, zirconium, manganese, iron, palladium, platinum, copper, silver, aluminum, and cerium.
7. The producing method according to claim 1 ,
wherein the tungsten oxide composite contains the metal element or the compound in a range of 0.01 mass % to 10 mass % as the amount of the metal element.