Anti-radiation multifunctional spectrum regulation optical metamaterial coating and preparation method thereof

Abstract

The invention relates to the field of paint coatings, in particular to an anti-radiation multifunctional spectrum regulation optical metamaterial coating and a preparation method thereof, and the preparation method comprises the following steps: adding a diluent into an organic polymer to obtain an organic polymer prepared solution; respectively adding quantitative high-refractive-index particles and a dispersing agent into the organic polymer preparation liquid, and mixing to obtain a coating semi-finished product; adding a quantitative curing agent into the coating semi-finished product, and mixing to obtain a coating finished product; and repeating the three steps, respectively preparing paint finished products with three particle sizes, and sequentially spraying the paint finished product with high-refractive-index particles with a first particle size, the paint finished product with high-refractive-index particles with a second particle size and the paint finished product with high-refractive-index particles with a third particle size on the surface of the object to be coated, forming the high-reflection bottom layer; ultraviolet-visible light wavelength conversion particles are added into an organic polymer configuration liquid, an anti-ultraviolet coating is obtained after uniform mixing, the surface of the high-reflection bottom layer can be coated with the anti-ultraviolet coating in a blade coating mode, a spray coating mode and the like, and an anti-ultraviolet middle layer is obtained after drying; the preparation method comprises the following steps: adding dye into an organic polymer preparation solution, uniformly mixing to obtain a colored coating, and coating the colored coating on the surface of the anti-ultraviolet intermediate layer in manners of blade coating, spray coating and the like to finally obtain the optical metamaterial coating which comprises the high-reflection bottom layer, the anti-ultraviolet intermediate layer and the colored surface layer from bottom to top.

Description

Technical Field

[0001] The present application relates to the field of paint coatings, and in particular to a radiation-resistant multifunctional spectral regulation optical metamaterial coating and a preparation method thereof. Background Art

[0002] Nowadays, there are a large number of outdoor buildings and a large number of outdoor equipment in the fields closely related to people's lives, such as energy storage and transportation, power transmission, and information transmission. In addition to being exposed to wind and rain, these facilities are also exposed to strong solar radiation for a long time. In the absence of effective protection measures, radiant heat can easily accumulate, resulting in a rapid increase in equipment temperature, a series of problems such as reduced strength due to surface aging, and equipment overheating and shutdown, which seriously affect the stability and reliability of the facilities. At present, there is no relevant technology that combines protection and passive cooling. As a conventional and efficient form of protection, coatings have great room for development and improvement. Therefore, it is urgent to develop a protective optical metamaterial coating that can provide excellent high-irradiation resistance while providing functional protection such as wear resistance, waterproofness, acid and alkali resistance, and salt spray resistance. It can protect outdoor buildings and equipment from the effects of radiation aging while reducing equipment thermal stress and equipment failure rate.

[0003] Patent CN114634727A discloses a radiation cooling coating structure for the outer surface of a building and its manufacturing method. By adding various additives to acrylate and adjusting their proportions, a kind of alkali-resistant and rust-resistant protective paint with good adhesion, good corrosion resistance and high gloss is obtained. The coating can be applied to cement substrates or steel substrates and play a good protective role. The coating proposed in this patent needs to add a variety of additives and raw materials during the preparation process, and the preparation process is complicated. In addition, the coating does not have strong radiation resistance, and its service life in outdoor exposure environment is unknown.

[0004] Patent CN202310903062 discloses a building exterior wall protective coating and its preparation method. By adding additives, titanium dioxide, tetrahedral radiation cooling fillers and other substances to organic polymer emulsion, a building radiation cooling coating is obtained. The coating achieves a solar reflectance of about 93% and an atmospheric window emissivity of 96%. Its high solar reflectance theoretically brings it a certain degree of radiation resistance, but its wear resistance and corrosion resistance have yet to be verified.

[0005] Patent CN116004026A discloses a radiant cooling paint with borate as the main filler. The paint uses borate as scattering particles, which not only forms a solar spectrum reflectivity of about 92%, but also has good anti-corrosion and anti-mildew effects. Although the paint of this invention is relatively simple to prepare, its solar spectrum reflectivity still has a lot of room for improvement.

[0006] Patent CN115851126A discloses a radiant cooling paint, a preparation method thereof and a radiant cooling coating, which uses n-hexane as a solvent and PDMS as a film-forming material to obtain a high emissivity. TiO2 and Y2O3 are added as fillers to reflect solar radiation. The coating uses PDMS as a substrate, has poor mechanical properties, and its tolerance to harsh outdoor environments is unknown.

[0007] Currently, there are few protective coatings for high-irradiation environments. The protective coatings used in outdoor facilities in high-irradiation areas cannot achieve both acid, alkali, salt spray, and erosion protection as well as high-irradiation resistance and cooling properties. This is mainly because these coatings lack optical design and cannot fundamentally solve the problems of surface aging and overheating in high-irradiation environments from an optical perspective. Therefore, the anti-radiation protection capabilities provided to buildings, equipment, etc. are limited. Summary of the invention

[0008] In summary, it is of great significance to develop a coating that has multiple protective effects such as resistance to acid, alkali, and salt spray, improves the solar radiation reflection characteristics of the coating from an optical perspective, achieves long-term high-efficiency radiation resistance, and provides a cooling effect for the equipment. Therefore, the present application provides a radiation-resistant multifunctional spectral regulation optical metamaterial coating with a layered structure and its preparation method and application, which can effectively prevent or weaken the temperature rise and aging phenomenon caused by solar radiation on the surface of an object, and avoid damage to the coating in harsh outdoor environments:

[0009] 1. A method for preparing a radiation-resistant multifunctional spectrally regulated optical metamaterial coating, the steps comprising: adding a diluent to an organic polymer to obtain an organic polymer solution; adding a certain amount of high-refractive index particles and a dispersant to the organic polymer solution and mixing to obtain a coating semi-finished product;

[0010] Adding a certain amount of curing agent into the semi-finished coating to obtain a finished coating;

[0011] Repeat the above three steps to prepare a finished coating product having high refractive index particles of a first particle size, a finished coating product having high refractive index particles of a second particle size, and a finished coating product having high refractive index particles of a third particle size, respectively, wherein the first particle size, the second particle size, and the third particle size satisfy the following relationship: the first particle size ≥ the second particle size ≥ the third particle size, wherein,

[0012] Spraying a coating product having high refractive index particles of a first particle size, a coating product having high refractive index particles of a second particle size, and a coating product having high refractive index particles of a third particle size on the surface of the object to be coated in sequence to form the high reflective bottom layer;

[0013] The UV-visible light wavelength conversion particles are added to the organic polymer preparation liquid, and after uniform mixing, an anti-UV coating is obtained. The anti-UV coating can be applied to the surface of the high-reflection bottom layer by scraping, spraying, etc., and after drying, an anti-UV intermediate layer is obtained.

[0014] 2. The method according to item 1 is characterized in that a dye is added to an organic polymer preparation liquid, and a colored surface layer coating is obtained after uniform mixing. The colored surface layer coating can be coated on the surface of the anti-ultraviolet intermediate layer by scraping, spraying, etc., and finally a multifunctional spectrally regulating optical metamaterial coating having a high-reflection base layer, an anti-ultraviolet intermediate layer and a colored surface layer is obtained.

[0015] 3. The method according to item 1 is characterized in that one or more of waterproof coatings, acid-proof coatings, alkali-proof coatings, and anti-corrosion coatings are also coated on the colored surface layer to constitute other functional layers.

[0016] 4. The method according to item 1, wherein the high-reflection bottom layer is prepared by mixing high-refractive index particles of various particle sizes and then coating the mixture on the object to be coated to obtain a high-reflection coating.

[0017] 5. The method according to item 1, wherein the thinner is selected from one or more of nitrocellulose lacquer thinner, perchlorethylene lacquer thinner, phenolic lacquer thinner, acrylic lacquer thinner, alkyd lacquer thinner, epoxy lacquer thinner, phenolic lacquer thinner and silicone lacquer thinner.

[0018] 6. The method according to item 1, wherein the organic polymer is selected from one or more of phenolic resin, polyamide resin, amino resin, alkyd resin, furan resin, polyester resin, vinyl resin, acrylic resin, epoxy resin and silicone resin.

[0019] 7. The method according to item 1, wherein the particle size of the high refractive index particles ranges from 100 to 3000 nm.

[0020] 8. The method according to item 7, wherein the high refractive index particles are selected from one or more materials such as titanium dioxide, silicon dioxide, zinc oxide, silicon carbide, silicon nitride, zinc sulfide, aluminum oxide, iron oxide, boron nitride, magnesium oxide, barium sulfate, barium carbonate and aluminum silicate.

[0021] 9. The method according to item 1, wherein the ultraviolet-visible light wavelength conversion particles are selected from one or more of fluorescein isothiocyanate, Oregon Green, carboxynaphthofluorescein, fluorescein isothiocyanate, rhodamine, oxadiazoles and their derivatives, triazoles and their derivatives, rhodamine and their derivatives, coumarin derivatives, 1,8-naphthalimide derivatives, pyrazoline derivatives, triphenylamine derivatives, porphyrin compounds, carbazole, pyrazine, thiazole derivatives, and perylene derivatives.

[0022] 10. The method according to item 1, wherein the dye is selected from one or more of medium chrome yellow, red iron oxide, iron yellow, iron blue, iron green, iron black, toluidine red, scarlet powder, and molybdenum chrome orange.

[0023] 11. The method according to item 1, wherein the dispersant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, cetyltrimethylammonium bromide, polyoxyethylene stearate, polyvinyl alcohol, sodium polyacrylate, polyacrylamide, polyphosphate, colloidal silicon, and hydroxyethyl cellulose.

[0024] 12. The method according to item 1, wherein the diluent is selected from one or more of ethyl acetate, butyl acetate, n-butanol, acetone, toluene, xylene, ethyl acetate, isobutanol, and methanol.

[0025] 13. The method according to item 1, wherein the curing agent is selected from one or more of aromatic polyamines, imidazoles, acid anhydrides, polyisocyanate curing agents, nitrogen-containing phenolic resins, aromatic ether ester diarylamines, acid anhydride curing agents, polyether amine curing agents, thiolamine epoxy curing agents, trimellitic anhydride, metaphenylenediamine curing agents, methyltetrahydrophthalic anhydride, and dicyandiamide.

[0026] 14. The method according to item 1, wherein the mass ratio of the curing agent to the organic polymer is 0.1:5-2:5.

[0027] 15. The method according to item 1, wherein the volume fraction of the high refractive index particles in the finished coating product is 0.5%-50%.

[0028] 16. An optical metamaterial coating, comprising:

[0029] A high-reflective bottom layer, comprising high-refractive index particles having a first particle size, high-refractive index particles having a second particle size, and high-refractive index particles having a third particle size, wherein the first particle size, the second particle size, and the third particle size satisfy the following relationship: the first particle size ≥ the second particle size ≥ the third particle size;

[0030] UV resistant middle layer;

[0031] Colored surface layer; and

[0032] Other functional layers.

[0033] 17. The optical metamaterial coating according to claim 16, wherein:

[0034] The thickness of the high-reflection bottom layer is 10-500 μm;

[0035] The thickness of the anti-ultraviolet intermediate layer is 10-500 μm;

[0036] The thickness of the colored surface layer is 10-500 μm;

[0037] The thickness of the other functional layer is 10-500 μm.

[0038] 18. An optical metamaterial coating according to item 16, wherein a high-reflection bottom layer, an anti-ultraviolet intermediate layer, a colored surface layer and other functional layers are arranged in sequence from bottom to top, and the high-reflection bottom layer is directly coated on the surface of the object to be coated.

[0039] 19. The optical metamaterial coating according to item 16, wherein the other functional layer has at least one or more of waterproof function, acid resistance function, alkali resistance function and anti-corrosion function.

[0040] 20. The optical metamaterial coating according to item 16, wherein the particle size of the high refractive index particles in the high reflective bottom layer is in the range of 100-3000 nm.

[0041] 21. An optical metamaterial coating according to item 16, wherein the volume fraction of the high refractive index particles in the high reflective bottom layer is 0.5%-50%.

[0042] 22. The optical metamaterial coating according to any one of items 16-21, which is prepared by the method described in any one of items 1-15.

[0043] 23. A radiation-resistant multifunctional spectrally regulated optical metamaterial coating, wherein the coating is prepared by the method described in any one of items 1 to 15.

[0044] 24. The radiation-resistant coating as described in any one of items 16 to 23 is used for passive cooling of various equipment and buildings under outdoor direct sunlight conditions.

[0045] The beneficial effects of this application are:

[0046] The present application provides an optical metamaterial coating with a hierarchical structure, which uses a polymer as a film-forming material and inorganic scattering nanoparticles of different particle sizes as coating fillers after hierarchical regulation. The hierarchical regulation further enhances the solar radiation wave reflectivity of the coating, optimizes the reflection path of radiation of different bands inside the coating, and enables the coating to obtain a stronger performance against high radiation. At the same time, ultraviolet-visible light wavelength conversion particles, colored pigments and other functional materials can be added to the polymer base in sequence / simultaneously to prepare an anti-ultraviolet intermediate layer, a colored surface layer and other functional layers to further improve the performance of the optical metamaterial coating. In actual tests, the coating did not produce any obvious changes on the surface after more than 2000 hours of artificial climate aging test and the surface temperature was reduced by about 20°C relative to the ordinary coating, showing extremely strong resistance to high radiation. The average reflectivity in the solar band is more than 93%, and at the same time, in the mid-infrared band of 8-13μm, its emissivity is more than 95%. At the same time, the high-radiation multifunctional spectral regulation coating of the present invention also has excellent waterproof performance, strong salt and alkali resistance, good adhesion characteristics and high hardness. In summary, this high-radiation resistant multifunctional spectral regulation optical metamaterial coating has a significant cooling effect while providing reliable protection for equipment in high-irradiation environments. It can effectively extend the service life of equipment in outdoor high-irradiation environments and reduce the incidence of thermal failures. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The accompanying drawings are used to better understand the present application and do not constitute an improper limitation on the present application.

[0048] Figure 1 This is a high-reflection bottom layer SEM of the radiation-resistant multifunctional spectral regulation optical metamaterial coating prepared by the present invention.

[0049] Figure 2 The simulation results of the reflectivity of the optical metamaterial coating in Example 1 of the present application are compared with those of the coating without a graded structure in Example 8, wherein the film thickness is 100 microns.

[0050] Figure 3 The temperature performance of ordinary metal fluorocarbon paint coating and the optical metamaterial coating of this application under outdoor solar radiation. DETAILED DESCRIPTION

[0051] The specific embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the specific embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present application and to fully convey the scope of the present application to those skilled in the art.

[0052] It should be noted that certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different nouns to refer to the same component. This specification and claims do not use the difference in nouns as a way to distinguish components, but use the difference in the functions of the components as the criterion for distinction. As mentioned throughout the specification and claims, "including" or "comprising" is an open term, so it should be interpreted as "including but not limited to". The subsequent description of the specification is a preferred embodiment of the implementation of the present application, but the description is based on the general principles of the specification and is not used to limit the scope of the present application. The scope of protection of the present application shall be determined by the attached claims.

[0053] In the present application specification, "first particle size" refers to the average particle size of high refractive index particles in a finished coating product composed of high refractive index particles; "second particle size" refers to the average particle size of high refractive index particles in a finished coating product composed of high refractive index particles; "third particle size" refers to the average particle size of high refractive index particles in a finished coating product composed of high refractive index particles; and the first particle size ≥ second particle size ≥ third particle size is satisfied.

[0054] The particle size test in the present invention adopts laser diffraction technology, and mainly uses Mastersizer3000+Ultra laser particle size analyzer to test the particle size and particle size distribution of the material. It achieves this by measuring the light intensity scattered when the laser beam passes through the dispersed particles. These data are then analyzed to calculate the particle size that produces the scattering model. The micro-nano particle samples to be tested must be pretreated to ensure that they are completely dispersed before they can be tested on the machine. The duration of background measurement using Mastersizer 3000+Ultra laser particle size analyzer is generally 10s; the duration of sample measurement is generally 10-12s, and the number of tests is generally 3 times. The equipment measurement results are shown as DI (intensity distribution) by default, and DI50 is selected as the particle size data of the corresponding micro-nano particles.

[0055] In this application specification, the term "optical metamaterial" is an artificial material containing nanostructures, whose special structures give them special optical properties, and their structures are obtained from at least two different materials (usually containing metal and dielectric material).

[0056] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, the steps of which include: adding a diluent to an organic polymer to obtain an organic polymer solution; adding a certain amount of high-refractive index particles and a dispersant to the organic polymer solution and mixing to obtain a coating semi-finished product;

[0057] Adding a certain amount of curing agent into the semi-finished coating to obtain a finished coating;

[0058] Repeat the above three steps to prepare a finished coating product having high refractive index particles of a first particle size, a finished coating product having high refractive index particles of a second particle size, and a finished coating product having high refractive index particles of a third particle size, respectively, wherein the first particle size, the second particle size, and the third particle size satisfy the following relationship: the first particle size ≥ the second particle size ≥ the third particle size, wherein,

[0059] The high-reflection bottom layer is formed by spraying a coating product having high-refractive index particles of a first particle size, a coating product having high-refractive index particles of a second particle size, and a coating product having high-refractive index particles of a third particle size on the surface of the object to be coated in sequence.

[0060] The UV-visible light wavelength conversion particles are added to the organic polymer preparation liquid, and after uniform mixing, an anti-UV coating is obtained. The anti-UV coating can be applied to the surface of the high-reflection bottom layer by scraping, spraying, etc., and after drying, an anti-UV intermediate layer is obtained.

[0061] The dye is added to the organic polymer preparation liquid, and after uniform mixing, a colored surface layer coating is obtained. The colored surface layer coating can be coated on the surface of the anti-ultraviolet intermediate layer by scraping, spraying, etc., and finally a multifunctional spectrally regulated optical metamaterial coating with a high-reflection base layer, an anti-ultraviolet intermediate layer and a colored surface layer is obtained.

[0062] In a specific embodiment of the present application, the resin is selected from one or more of phenolic resin, polyamide resin, amino resin, alkyd resin, furan resin, polyester resin, vinyl resin, acrylic resin, epoxy resin and silicone resin.

[0063] In a specific embodiment of the present application, the refractive index of the multifunctional spectrally regulated optical metamaterial coating can be controlled by the type and concentration of the added nanoparticles (i.e., high refractive index particles), and one or more high refractive index particles can be selected to be added to the multifunctional spectrally regulated optical metamaterial coating.

[0064] In a specific embodiment of the present application, the refractive index of the multifunctional spectrally regulated optical metamaterial coating can be controlled by the type and concentration of the added nanoparticles (i.e., high refractive index particles). For example, the high refractive index particles can be titanium dioxide, silicon dioxide, zinc oxide, silicon carbide, silicon nitride, zinc sulfide, aluminum oxide, iron oxide, boron nitride, magnesium oxide, barium sulfate, barium carbonate and aluminum silicate.

[0065] In a specific embodiment of the present application, the refractive index of the multifunctional spectrally regulated optical metamaterial coating can be controlled by the type and concentration of the added nanoparticles (i.e., high refractive index particles), and the particle size range of the high refractive index particles is 100-3000nm, for example, it can be 100nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, 550nm, 600nm, 650nm, 700nm, 750nm, 800nm, 850nm, 900nm, 950nm, 1000nm, 1050nm, 1100nm, 1150nm, 1200nm, 1250nm , 1300nm, 1350nm, 1400nm, 1450nm, 1500nm, 1550nm, 1600nm, 1650nm, 1700 nm, 1750nm, 1800nm, 1850nm, 1900nm, 1950nm, 2000nm, 2050nm, 2100nm, 215 0nm, 2200nm, 2250nm, 2300nm, 2350nm, 2400nm, 2450nm, 2500nm, 2550nm, 2 600nm, 2650nm, 2700nm, 2750nm, 2800nm, 2850nm, 2900nm, 2950nm, 3000nm.

[0066] In a specific embodiment of the present application, the ultraviolet-visible light wavelength conversion particles are selected from one or more of fluorescein isothiocyanate, Oregon Green, carboxynaphthofluorescein, fluorescein isothiocyanate, rhodamine, oxadiazole and its derivatives, triazole and its derivatives, rhodamine and its derivatives, coumarin derivatives, 1,8-naphthalimide derivatives, pyrazoline derivatives, triphenylamine derivatives, porphyrin compounds, carbazole, pyrazine, thiazole derivatives, and perylene derivatives.

[0067] In a specific embodiment of the present application, the dye can bring a colored surface layer of one or more colors to the multifunctional spectrally regulated optical metamaterial coating. For example, the dye can be one or more of medium chrome yellow, iron oxide red, iron yellow, iron blue, iron green, iron black, toluidine red, scarlet powder, and molybdenum chrome orange.

[0068] In a specific embodiment of the present application, another functional layer is coated on the colored surface layer, and the other functional layer may be another functional layer having a waterproof function and composed of a waterproof coating.

[0069] In a specific embodiment of the present application, another functional layer is coated on the colored surface layer, and the other functional layer may be another functional layer composed of an acid-proof coating and having an acid-proof function.

[0070] In a specific embodiment of the present application, another functional layer is coated on the colored surface layer, and the other functional layer may be another functional layer composed of an alkali-proof coating and having an alkali-proof function.

[0071] In a specific embodiment of the present application, another functional layer is coated on the colored surface layer, and the other functional layer may be another functional layer having an anti-corrosion function and composed of an anti-corrosion coating.

[0072] In a specific embodiment of the present application, the dispersant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, hexadecyltrimethylammonium bromide, polyoxyethylene stearate, polyvinyl alcohol, sodium polyacrylate, polyacrylamide, polyphosphate, colloidal silicon, and hydroxyethyl cellulose.

[0073] In a specific embodiment of the present application, the diluent is selected from one or more of ethyl acetate, butyl acetate, n-butanol, acetone, toluene, xylene, ethyl acetate, isobutanol, and methanol.

[0074] In a specific embodiment of the present application, the curing agent is selected from one or more of aromatic polyamines, imidazoles, acid anhydrides, polyisocyanate curing agents, nitrogen-containing phenolic resins, aromatic ether ester diarylamines, acid anhydride curing agents, polyether amine curing agents, thiolamine epoxy curing agents, trimellitic anhydride, metaphenylenediamine curing agents, methyltetrahydrophthalic anhydride, and dicyandiamide.

[0075] In a specific embodiment of the present application, in the finished coating product, the mass ratio of the added curing agent to the organic polymer is 0.1:5 to 2:5, for example, it can be 0.1:5, 0.2:5, 0.3:5, 0.4:5, 0.5:5, 0.6:5, 0.7:5, 0.8:5, 0.9:5, 1:5, 1.1:5, 1.2:5, 1.3:5, 1.4:5, 1.5:5, 1.6:5, 1.7:5, 1.8:5, 1.9:5, 2:5.

[0076] The present application provides an optical metamaterial coating, which includes a high-reflection bottom layer, wherein the high-reflection bottom layer includes high-refractive index particles with a first particle size, high-refractive index particles with a second particle size, and high-refractive index particles with a third particle size, wherein the first particle size, the second particle size, and the third particle size satisfy the following relationship: the first particle size ≥ the second particle size ≥ the third particle size; an anti-ultraviolet intermediate layer; a colored surface layer; and other functional layers.

[0077] In a specific embodiment of the present application, the first particle size satisfies being larger than the second particle size. Preferably, the first particle size satisfies a range of 1000-3000nm, for example, 1001nm, 1050nm, 1100nm, 1150nm, 1200nm, 1250nm, 1300nm, 1350nm, 1400nm, 1450nm, 1500nm, 1550nm, 1600nm, 1650nm, 1700nm, 1750nm, 1800nm, 1850nm, 1900nm, 1950nm, 2000nm, 2050nm, 2100nm, 2150nm, 2200nm, 2250nm, 2300nm, 2350nm, 240 0nm, 2450nm, 2500nm, 2550nm, 2600nm, 2650nm, 2700nm, 2750nm, 2800nm, 2850nm, 2900nm, 2950nm, 3000nm.

[0078] In a specific embodiment of the present application, the second particle size is greater than the third particle size and smaller than the first particle size. Preferably, the second particle size is in the range of 600-1000nm, for example, it can be 601nm, 650nm, 700nm, 750nm, 800nm, 850nm, 900nm, 950nm, 1000nm.

[0079] In a specific embodiment of the present application, the third particle size is smaller than the second particle size. Preferably, the third particle size is in the range of 100-600nm, for example, it can be 101nm, 150nm, 200nm, 250nm, 300nm, 350nm, 400nm, 450nm, 500nm, 550nm, 600nm.

[0080] In a specific embodiment of the present application, the volume fraction of the high refractive index particles in the finished coating is 0.5%-50%, for example, it can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, 10%, 10.5%, 11%, 11.5%, 12%, 12.5%, 13%, 13.5%, 14%, 14.5%, 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, 18%, 18.5%, 19%, 19.5%, 20%, 20.5%, 21%, 21.5%, 22%, 22.5%, 23%, 23.5%, 24%, 24.5%, 25%, 25.5%, 26%, 26.5%, 27%, 27.5%, 28%, 28.5%, 29%, 29.5%, 30%, 30.5%, 31%, 31.5%, 32%, 32.5%, 33%, 33.5%, 34%, 34.5%, 35%, 35.5%, 36%, 36.5%, 37%, 38.5%, 39%, 39.5%, 40%, 40.5%, 41%, 41.5%, 42%, 42.5%, 43%, 43.5%, 44%, 44.5%, 45%, 45.5%, 46%, 46.5%, 47%, 47.5%, 48%, 48.5%, 49%, 49.5%, 50%.

[0081] In a specific embodiment of the present application, the thickness of the high reflective bottom layer is 10-500 μm, for example, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm, 110 μm, 115 μm, 120μm, 125μm, 130μm, 135μm, 140μm, 145μm, 150μm, 155μm, 160μm, 165μm, 170μm, 175μm, 180μm , 185μm, 190μm, 195μm, 200μm, 205μm, 210μm, 215μm, 220μm, 225μm, 230μm, 235μm, 240μm, 245μm m, 250μm, 255μm, 260μm, 265μm, 270μm, 275μm, 280μm, 285μm, 290μm, 295μm, 300μm, 305μm, 310 μm, 315μm, 320μm, 325μm, 330μm, 335μm, 340μm, 345μm, 350μm, 355μm, 360μm, 365μm, 370μm, 37 5μm, 380μm, 385μm, 390μm, 395μm, 400μm, 405μm, 410μm, 415μm, 420μm, 425μm, 430μm, 435μm, 4 40μm, 445μm, 450μm, 455μm, 460μm, 465μm, 470μm, 475μm, 480μm, 485μm, 490μm, 495μm, 500μm.

[0082] In a specific embodiment of the present application, the thickness of the anti-ultraviolet intermediate layer is 10-500 μm, for example, it can be 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm, 110 μm, 115 μm , 120μm, 125μm, 130μm, 135μm, 140μm, 145μm, 150μm, 155μm, 160μm, 165μm, 170μm, 175μm, 180μm m, 185μm, 190μm, 195μm, 200μm, 205μm, 210μm, 215μm, 220μm, 225μm, 230μm, 235μm, 240μm, 245 μm, 250μm, 255μm, 260μm, 265μm, 270μm, 275μm, 280μm, 285μm, 290μm, 295μm, 300μm, 305μm, 31 0μm, 315μm, 320μm, 325μm, 330μm, 335μm, 340μm, 345μm, 350μm, 355μm, 360μm, 365μm, 370μm, 3 75μm, 380μm, 385μm, 390μm, 395μm, 400μm, 405μm, 410μm, 415μm, 420μm, 425μm, 430μm, 435μm, 440μm, 445μm, 450μm, 455μm, 460μm, 465μm, 470μm, 475μm, 480μm, 485μm, 490μm, 495μm, 500μm.

[0083] In a specific embodiment of the present application, the thickness of the colored surface layer is 10-500 μm, for example, it can be 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm, 110 μm, 115 μm, 120μm, 125μm, 130μm, 135μm, 140μm, 145μm, 150μm, 155μm, 160μm, 165μm, 170μm, 175μm, 180μm , 185μm, 190μm, 195μm, 200μm, 205μm, 210μm, 215μm, 220μm, 225μm, 230μm, 235μm, 240μm, 245μm m, 250μm, 255μm, 260μm, 265μm, 270μm, 275μm, 280μm, 285μm, 290μm, 295μm, 300μm, 305μm, 310 μm, 315μm, 320μm, 325μm, 330μm, 335μm, 340μm, 345μm, 350μm, 355μm, 360μm, 365μm, 370μm, 37 5μm, 380μm, 385μm, 390μm, 395μm, 400μm, 405μm, 410μm, 415μm, 420μm, 425μm, 430μm, 435μm, 4 40μm, 445μm, 450μm, 455μm, 460μm, 465μm, 470μm, 475μm, 480μm, 485μm, 490μm, 495μm, 500μm.

[0084] In a specific embodiment of the present application, the thickness of the other functional layer is 10-500 μm, for example, it can be 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm, 95 μm, 100 μm, 105 μm, 110 μm, 115 μm, 120μm, 125μm, 130μm, 135μm, 140μm, 145μm, 150μm, 155μm, 160μm, 165μm, 170μm, 175μm, 180μm , 185μm, 190μm, 195μm, 200μm, 205μm, 210μm, 215μm, 220μm, 225μm, 230μm, 235μm, 240μm, 245μm m, 250μm, 255μm, 260μm, 265μm, 270μm, 275μm, 280μm, 285μm, 290μm, 295μm, 300μm, 305μm, 310 μm, 315μm, 320μm, 325μm, 330μm, 335μm, 340μm, 345μm, 350μm, 355μm, 360μm, 365μm, 370μm, 37 5μm, 380μm, 385μm, 390μm, 395μm, 400μm, 405μm, 410μm, 415μm, 420μm, 425μm, 430μm, 435μm, 4 40μm, 445μm, 450μm, 455μm, 460μm, 465μm, 470μm, 475μm, 480μm, 485μm, 490μm, 495μm, 500μm.

[0085] In a specific embodiment of the present application, the optical metamaterial coating is used for passive cooling of various equipment, buildings, etc. under outdoor direct sunlight conditions. The optical metamaterial coating and ordinary metal fluorocarbon coating are placed together in the same outdoor solar radiation environment, and the temperature changes as shown in FIG. Figure 3 shown.

[0086] Example 1

[0087] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, which comprises the following steps:

[0088] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0089] S2. Mix 190 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer solution prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0090] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a coating product A with a particle size of 1000 nm.

[0091] Repeat the above steps S1-S3, and use 700nm and 400nm titanium dioxide to replace the original 1000nm titanium dioxide to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection bottom layer, a second high reflection bottom layer and a third high reflection bottom layer, each of which has a thickness of 100μm and a titanium dioxide particle volume fraction of 25%. After drying, a high reflection bottom layer is obtained, see Figure 1 As shown in SEM picture.

[0092] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0093] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0094] The colored surface layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet middle layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0095] Example 2

[0096] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, which comprises the following steps:

[0097] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0098] S2. Mix 115 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer solution prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0099] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a coating product A with a particle size of 1000 nm.

[0100] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of titanium dioxide particles of 15%, and a high reflection bottom layer is obtained after drying.

[0101] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0102] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0103] The surface of the anti-ultraviolet intermediate layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet intermediate layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0104] Example 3

[0105] A method for preparing a radiation-resistant coating comprises the following steps:

[0106] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0107] S2. Mix 190 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer solution prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0108] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer at a speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a finished coating product A.

[0109] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of titanium dioxide particles of 25%, and a high reflection bottom layer is obtained after drying.

[0110] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0111] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of dye and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0112] The colored surface layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet middle layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0113] Example 4

[0114] A method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating comprises the following steps:

[0115] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0116] S2. Mix 115 g of silicon dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer solution prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0117] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer at a speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a finished coating product A.

[0118] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of silicon dioxide particles of 15%, and a high reflection bottom layer is obtained after drying.

[0119] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0120] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0121] The surface of the anti-ultraviolet intermediate layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet intermediate layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0122] Example 5

[0123] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, which comprises the following steps:

[0124] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0125] S2. Mix 266 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer formulation prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0126] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a coating product A with a particle size of 1000 nm.

[0127] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of titanium dioxide particles of 35%, and a high reflection bottom layer is obtained after drying.

[0128] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0129] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0130] The surface of the anti-ultraviolet intermediate layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet intermediate layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0131] Example 6

[0132] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, which comprises the following steps:

[0133] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0134] S2. Mix 266 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer formulation prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0135] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a coating product A with a particle size of 1000 nm.

[0136] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of titanium dioxide particles of 35%, 25% and 15% respectively, and a high reflection bottom layer is obtained after drying.

[0137] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0138] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0139] The surface of the anti-ultraviolet intermediate layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet intermediate layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0140] Example 7

[0141] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, which comprises the following steps:

[0142] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0143] S2. Mix 266 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer formulation prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0144] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a coating product A with a particle size of 1000 nm.

[0145] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of titanium dioxide particles of 15%, 25% and 35% respectively, and a high reflection bottom layer is obtained after drying.

[0146] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0147] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0148] The surface of the anti-ultraviolet intermediate layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflection bottom layer, the anti-ultraviolet intermediate layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0149] Example 8

[0150] A method for preparing a coating comprises the following steps:

[0151] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0152] S2. Mix 64 g of titanium dioxide particles with diameters of 400 nm, 700 nm and 1000 nm, a total of 192 g of titanium dioxide powder, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer formulation prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25°C. Stirring is continued for 25 minutes to finally obtain a semi-finished coating product.

[0153] S3. Mix the obtained in S2 with 90g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800r / min and an ambient temperature of 25°C for 10 minutes to finally obtain a finished coating; spray the finished coating on the surface of a metal substrate with a thickness of 300μm and a volume fraction of titanium dioxide particles of 25%.

[0154] S4, 100g of acrylic resin varnish and 27g of methanol were mixed and stirred for 30 minutes, 0.5g of fluorescein isothiocyanate and 0.07g of sodium dodecyl sulfate were added, and stirred for 20 minutes, and then polyisocyanate curing agent was added and mixed and stirred to obtain a wavelength conversion coating solution. The solution was sprayed on the surface of the high-reflection bottom layer, dried, and cured to obtain an anti-ultraviolet intermediate layer.

[0155] S5, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the anti-ultraviolet intermediate layer, dried, and cured to obtain a colored surface layer.

[0156] Comparative Example 1

[0157] The present application provides a method for preparing a radiation-resistant multifunctional spectral control optical metamaterial coating, which comprises the following steps:

[0158] S1. 180 g of acrylic resin varnish was mixed with 27 g of methanol. The stirring tool was a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring was continued for 15 minutes to finally obtain an organic polymer formulation liquid.

[0159] S2. Mix 266 g of titanium dioxide powder with a diameter of 1000 nm, 3.8 g of sodium dodecylbenzene sulfonate and the organic polymer formulation prepared in S1. The stirring tool is a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. The stirring lasts for 25 minutes to finally obtain a semi-finished coating product.

[0160] S3. Mix the obtained in S2 with 90 g of polyisocyanate curing agent, using a magnetic stirrer with a rotation speed of 800 r / min and an ambient temperature of 25° C. for 10 minutes to finally obtain a coating product A with a particle size of 1000 nm.

[0161] Repeat the above steps S1-S3, and use titanium dioxide with particle sizes of 700nm and 400nm to replace the original titanium dioxide with particle size of 1000nm to prepare a coating product B with a particle size of 700nm and a coating product C with a particle size of 400nm. The three coating products AC are sprayed on the surface of the metal substrate in sequence to form a first high reflection layer, a second high reflection layer and a third high reflection layer with a thickness of 100μm and a volume fraction of titanium dioxide particles of 15%, 25% and 35% respectively, and a high reflection coating is obtained after drying.

[0162] S4, 100g of acrylic resin varnish and 27g of methanol are mixed and stirred for 30 minutes, 0.3g of iron blue and 0.07g of sodium dodecyl sulfate are added, and stirred for 20 minutes, and then polyisocyanate curing agent is added and mixed and stirred to obtain a colored coating solution. The colored surface layer coating is sprayed on the surface of the high-reflective bottom layer, dried, and cured to obtain a colored surface layer.

[0163] The surface of the high-reflective bottom layer is coated with a waterproof coating to obtain a coating with a waterproof function. In general, the composite material of the high-reflective bottom layer, the colored surface layer and the waterproof layer is called an anti-radiation multifunctional spectral regulation optical metamaterial coating.

[0164] Table 1 Reflection results of different coatings

[0165]

[0166]

[0167] By comparing Example 1 with Example 2, it can be found that reducing the titanium dioxide content in the high-reflection bottom layer from 25% to 15% will result in a decrease in the reflectivity of the overall coating. By comparing Example 1 with Example 3, it can be found that reducing the thickness of the high-reflection bottom layer from 100μm to 80μm will result in a decrease in the reflectivity of the overall coating. By comparing Example 2 with Example 4, it can be found that the high-reflection bottom layer with titanium dioxide as the high-refractive index particles will have a better solar radiation band reflectivity than the high-reflection bottom layer with silicon dioxide as the high-refractive index particles. By comparing Example 1 with Example 5, it can be found that increasing the titanium dioxide content in the high-reflection bottom layer from 25% to 35% will result in a decrease in the reflectivity of the overall coating. This is because the high-refractive index particle content causes agglomeration, thereby affecting the reflective performance of the overall coating. By comparing Example 1 with Example 6 and Example 7, it can be found that the reflectivity of the coating is optimal when the volume fraction of the three particle sizes of particles in their respective layers is 25%. By comparing Example 7 with Comparative Example 1, it can be found that the anti-ultraviolet intermediate layer composed of ultraviolet-visible light wavelength conversion particles has an effect of improving the reflectivity of the overall coating. Figure 2As shown, it can be found that blending high refractive index particles of different sizes will reduce the overall reflectivity of the coating, proving that the layered structure design of the coating is very necessary.

[0168] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0169] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A method for preparing an optical metamaterial coating, comprising the steps of: Adding a diluent to an organic polymer to obtain an organic polymer formulation; Adding a certain amount of high refractive index particles and a dispersant to the organic polymer solution and mixing to obtain a semi-finished coating product; Adding a certain amount of curing agent into the semi-finished coating to obtain a finished coating; Repeat the above three steps to prepare a finished coating product having high refractive index particles of a first particle size, a finished coating product having high refractive index particles of a second particle size, and a finished coating product having high refractive index particles of a third particle size, respectively, wherein the first particle size, the second particle size, and the third particle size satisfy the following relationship: the first particle size ≥ the second particle size ≥ the third particle size, wherein, Spraying a coating product having high refractive index particles of a first particle size, a coating product having high refractive index particles of a second particle size, and a coating product having high refractive index particles of a third particle size on the surface of the object to be coated in sequence to form the high reflective bottom layer; The UV-visible light wavelength conversion particles are added to the organic polymer preparation liquid, and after uniform mixing, an anti-UV coating is obtained. The anti-UV coating can be applied to the surface of the high-reflection bottom layer by scraping, spraying, etc., and after drying, an anti-UV intermediate layer is obtained.

2. The method according to claim 1, wherein: A colored surface layer is coated on the anti-ultraviolet intermediate layer, and a dye is added to an organic polymer configuration liquid. After uniform mixing, a colored surface layer coating is obtained. The colored surface layer coating can be coated on the surface of the anti-ultraviolet intermediate layer by scraping, spraying, etc., and finally an optical metamaterial coating with a high-reflection base layer, an anti-ultraviolet intermediate layer and a colored surface layer is obtained.

3. The method according to claim 1, characterized in that One or more of waterproof coating, acid-proof coating, alkali-proof coating and anti-corrosion coating are also coated on the colored surface layer to form other functional layers.

4. The method according to claim 1, wherein: The high-reflection bottom layer is prepared by mixing high-refractive index particles of various particle sizes and then coating the object to be coated to obtain a high-reflection coating.

5. The method according to claim 1, wherein: The thinner is selected from one or more of nitrocellulose lacquer thinner, perchlorethylene lacquer thinner, phenolic lacquer thinner, acrylic lacquer thinner, alkyd lacquer thinner, epoxy lacquer thinner, phenolic lacquer thinner and silicone lacquer thinner.

6. The method according to claim 1, wherein: The organic polymer is selected from one or more of phenolic resin, polyamide resin, amino resin, alkyd resin, furan resin, polyester resin, vinyl resin, acrylic resin, epoxy resin and silicone resin.

7. The method according to claim 1, wherein: The particle size of the high refractive index particles ranges from 100 to 3000 nm.

8. The method according to claim 7, wherein: The high refractive index particles are selected from one or more materials such as titanium dioxide, silicon dioxide, zinc oxide, silicon carbide, silicon nitride, zinc sulfide, aluminum oxide, iron oxide, boron nitride, magnesium oxide, barium sulfate, barium carbonate and aluminum silicate.

9. The method according to claim 1, wherein: The ultraviolet-visible light wavelength conversion particles are selected from one or more of fluorescein isothiocyanate, Oregon green, carboxy naphthofluorescein, fluorescein isothiocyanate, rhodamine, oxadiazole and its derivatives, triazole and its derivatives, rhodamine and its derivatives, coumarin derivatives, 1,8-naphthalimide derivatives, pyrazoline derivatives, triphenylamine derivatives, porphyrin compounds, carbazole, pyrazine, thiazole derivatives, and perylene derivatives.

10. The method according to claim 1, wherein: The dye is selected from one or more of medium chrome yellow, red iron oxide, iron yellow, iron blue, iron green, iron black, toluidine red, scarlet powder, and molybdenum chrome orange.

11. The method according to claim 1, wherein: The dispersant is selected from one or more of sodium dodecyl sulfate, sodium dodecylbenzene sulfonate, hexadecyltrimethylammonium bromide, polyoxyethylene stearate, polyvinyl alcohol, sodium polyacrylate, polyacrylamide, polyphosphate, colloidal silicon, and hydroxyethyl cellulose.

12. The method according to claim 1, wherein: The diluent is selected from one or more of ethyl acetate, butyl acetate, n-butanol, acetone, toluene, xylene, ethyl acetate, isobutanol and methanol.

13. The method according to claim 1, wherein: The curing agent is selected from one or more of aromatic polyamines, imidazoles, acid anhydrides, polyisocyanate curing agents, nitrogen-containing phenolic resins, aromatic ether ester diarylamines, acid anhydride curing agents, polyether amine curing agents, thiolamine epoxy curing agents, trimellitic anhydride, metaphenylenediamine curing agents, methyltetrahydrophthalic anhydride, and dicyandiamide.

14. The method according to claim 1, wherein: The mass ratio of the curing agent to the organic polymer is 0.1:5-2:

5.

15. The method according to claim 1, wherein: The volume fraction of the high refractive index particles in the finished coating product is 0.5%-50%.

16. An optical metamaterial coating, comprising: A high-reflective bottom layer, comprising high-refractive index particles having a first particle size, high-refractive index particles having a second particle size, and high-refractive index particles having a third particle size, wherein the first particle size, the second particle size, and the third particle size satisfy the following relationship: the first particle size ≥ the second particle size ≥ the third particle size; UV resistant middle layer; Colored surface layer; and Other functional layers.

17. The optical metamaterial coating according to claim 16, wherein: The thickness of the high-reflection bottom layer is 10-500 μm; The thickness of the anti-ultraviolet intermediate layer is 10-500 μm; The thickness of the colored surface layer is 10-500 μm; The thickness of the other functional layer is 10-500 μm.

18. The optical metamaterial coating of claim 16, wherein: The high-reflection bottom layer, the anti-ultraviolet middle layer, the colored surface layer and other functional layers are arranged in sequence from bottom to top, and the high-reflection bottom layer is directly arranged on the surface of the object to be coated.

19. The optical metamaterial coating of claim 16, wherein: The other functional layer has at least one or more of waterproof function, acid resistance function, alkali resistance function and anti-corrosion function.

20. The optical metamaterial coating of claim 16, wherein: The particle size of the high refractive index particles in the high reflective bottom layer ranges from 100 to 3000 nm.

21. The optical metamaterial coating of claim 16, wherein: The volume fraction of the high refractive index particles in the high reflective bottom layer is 0.5%-50%.

22. The optical metamaterial coating according to any one of claims 16 to 21, which is prepared by the method according to any one of claims 1 to 15.

23. An optical metamaterial coating, wherein: It is prepared by the method according to any one of claims 1 to 15.

24. The optical metamaterial coating according to any one of claims 16 to 23 is used for passive cooling of various equipment and buildings under outdoor direct sunlight conditions.

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