# US 12,760,190 B2 · Coating composition, its preparation and use in reducing heat gain > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,760,190 B2 - Document ID: US12760190B2 - Status: Granted - Kind: B2 - Application number: 18/061,624 - Filed: 2022-12-05 - Published: 2024-06-06 - Granted: 2026-10-13 - Earliest claimed: 2022-12-05 - Assignees: City University of Hong Kong - Applicants: City University of Hong Kong - Inventors: Dangyuan Lei; Xue Ma; Yang Fu - Web page: https://patentgrep.com/patent/US12760190B2 ## CPC - C09D 7/70: {characterised by shape, e.g. fibres, flakes or microspheres} - C08K 3/40: Glass - C08K 7/20: Glass - C09D 5/18: Fireproof paints {including high temperature resistant paints} - C09D 7/61: inorganic - C09K 11/7734: {Aluminates} - C08K 2003/2241: {Titanium dioxide} - C08K 2201/005: Additives being defined by their particle size in general - C09D 7/66: {characterised by particle size} - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE ## Abstract A coating composition for reducing heat gain of an article includes TiO2 particles; hollow glass microspheres; a phosphor material having a quantum yield of at least about 90% and an excitation wavelength from about 250 nm to about 440 nm, matching those of the TiO2 particles; and a polymer. Also a method for reducing heat gain of an article by using the coating composition of the present invention. ## Claims ### Claim 1 A coating composition for reducing heat gain of an article, comprising: TiO2 particles; hollow glass microspheres; phosphor material particles having a quantum yield of at least about 90% and an excitation wavelength range from about 250 nm to about 440 nm, said excitation wavelength range matching that of the TiO2 particles, thereby enhancing heat gain reduction of the coating composition; and a polymer matrix; wherein the TiO2 particles have a weight percentage of about 10% wt to about 30% wt with respect to the coating composition; and the phosphor material particles are BaMgAl10O17:Eu2+, having a weight percentage of about 4% wt to about 8% wt with respect to the coating composition; wherein the TiO2 particles and the phosphor material particles are sized and formulated relative to each other such that the TiO2 particles adhere to and assemble into a dielectric shell around the phosphor material particles, the coated phosphor material particles having a Purcell factor of about 2.6. ### Claim 2 (depends on 1) The coating composition as claimed in claim 1, wherein the phosphor material has a particle size of about 8 μm to about 15 μm. ### Claim 3 (depends on 1) The coating composition as claimed in claim 1, wherein the TiO2 particles comprise a rutile crystal structure, an anatase crystal structure, or a mixture thereof. ### Claim 4 (depends on 1) The coating composition as claimed in claim 1, wherein the hollow glass microspheres comprise a coating selected from the group consisting of silver, nickel, zinc(II) oxide, TiO2 with anatase form, TiO2 with the rutile form, and a combination thereof. ### Claim 5 (depends on 1) The coating composition as claimed in claim 1, wherein the polymer matrix is selected from the group consisting of polystyrene, polyacrylate, polyalkylacrylate, polymethacrylate, polyalkylmethacrylate, polycarbonate, polyacryclic acid, polymethacrylic acid, and mixtures thereof, and copolymers thereof. ### Claim 6 (depends on 1) The coating composition as claimed in claim 1, wherein the polymer matrix is polystyrene acrylic emulsion polymer. ### Claim 7 (depends on 1) The coating composition as claimed in claim 1, wherein the polymer matrix has a weight percentage of about 45% wt to about 60% wt with respect to the coating composition. ### Claim 8 (depends on 1) The coating composition as claimed in claim 1, wherein the coating composition, when applied on the article, reduces the heat gain of the article by at least about 15° C. ### Claim 9 (depends on 1) The coating composition as claimed in claim 1, wherein the coating composition has an enhanced net cooling power by about 28 W/m2 caused by the presence of phosphor material. ### Claim 10 (depends on 1) The coating composition as claimed in claim 1, wherein the article comprises infrastructure, clothing, or an automobile. ### Claim 11 (depends on 1) The coating composition as claimed in claim 1, further comprising a wetting agent, a dispersant agent, an antifoaming agent, a suspending agent, a levelling agent, a film-forming agent, water, or a mixture thereof. ### Claim 12 (depends on 1) A method for reducing heat gain of an article by using the coating composition as claimed in claim 1, comprising the steps of: a) providing a mixture comprising the coating composition as claimed in claim 1 and one or more additives; and b) applying the mixture on a surface of the article thereby forming a layer of coating thereon. ### Claim 13 (depends on 12) The method as claimed in claim 12, wherein the one or more additives comprises a wetting agent, a dispersant agent, an antifoaming agent, a suspending agent, a levelling agent, a film-forming agent, water, or a mixture thereof. ### Claim 14 (depends on 12) The method as claimed in claim 12, wherein step b) comprises a step of spraying the mixture on the surface of the article at a predefined pressure.