CN102277023A - Transparent heat-insulation coating for glass and preparation method thereof - Google Patents

Abstract

A glass transparent heat-insulating coating and its preparation method, the coating contains cesium tungsten bronze powder with a general formula of Cs _0.1-3.5 WO ₃ , and the crystal phase composition of the powder is Cs _0.2 WO ₃ or Cs _0.32 WO ₃ , the particle size of the powder is 100-1300nm, and the specific surface area is 7-50m ² /g. The glass transparent heat-insulating coating of the present invention has the functions of visible light transmission and near-infrared shielding, and has the function of light self-regulation, that is, with the extension of light intensity and light time, the effects of visible light transmission and near-infrared shielding will be further enhanced , so it is especially suitable for preparing transparent thermal insulation film on the surface of glass. It is an intelligent transparent thermal insulation coating for glass and has broad application prospects in the fields of thermal insulation of architectural window glass and automotive glass. The coating has simple components and is suitable for large-scale industrial production and practical application.

Description

A kind of glass transparent heat-insulating coating and preparation method thereof

technical field

The invention relates to a novel glass heat-insulation coating with near-infrared shielding function, in particular to a glass transparent heat-insulation coating containing cesium tungsten bronze powder and a preparation method thereof.

Background technique

Traditional glass can transmit light, but its thermal insulation performance is poor. The wavelength distribution of solar radiation is 300-2500nm, of which the ultraviolet part accounts for 14%, the visible part accounts for 40%, and the infrared part accounts for 44%. Glass transparent heat-insulating coating is a functional coating that is coated on the surface of glass to reduce the near-infrared shielding coefficient of glass as the main heat-insulating method under the premise of maintaining a certain visible light transmittance. Oxide particles currently commonly used in the preparation of glass transparent thermal insulation coatings include indium tin oxide (ITO) (Electroceram, 2009, 23: 361-366), antimony tin oxide (ATO) (Thin solid film, 1997, 295: 95-100 ), aluminum zinc oxide (AZO) (Electroceram, 2009, 23:341-345) and other powders. In recent years, tungsten bronze has attracted widespread attention because of its interesting photoelectric properties, photochromism and superconductivity. Cesium tungsten bronze (Cs _x WO ₃ ) formed by doping monovalent cation Cs ⁺ in tungsten oxide has Excellent low-temperature superconducting properties and low resistivity near room temperature. Recently, studies have found that transparent films on glass surfaces made of hexagonal cesium tungsten bronze (Cs _x WO ₃ ) have better visible light transmission and near-infrared light shielding properties than ITO films (J.Am.Ceram.Soc. , 2007, 90(12): 4059-4061; Journal of Solid State Chemistry, 2010, 183(10): 2456-2460). Cesium tungsten bronze powder will be used as a new type of near-infrared shielding material, widely used in the preparation of transparent heat-insulating coatings or heat-insulating films on glass surfaces, and has broad application prospects in energy-saving building window glass and automotive glass heat insulation.

Therefore, the present invention provides a glass surface transparent heat-insulating coating added with Cs _x WO ₃ powder and a preparation method thereof.

Contents of the invention

One of the objectives of the present invention is to provide a novel transparent heat-insulating coating for glass surfaces (hereinafter referred to as coating) and a preparation method thereof. The coating contains cesium tungsten bronze powder with a general formula of Cs _0.1-3.5 WO ₃ , the crystal phase composition of the powder is Cs _0.2 WO ₃ or Cs _0.32 WO ₃ , the particle size of the powder is 100-1300 nm, and the specific surface area is 7-50m ² /g.

The content of cesium tungsten bronze powder in the paint of the present invention is 0.0135-0.05g/ml.

The paint of the present invention also contains polyvinyl butyral (PVB), polyvinyl alcohol (PVA) or collodion as a film forming agent.

The present invention further provides a method for preparing the above coating, including the step of mixing the cesium tungsten bronze powder mentioned above with a film-forming agent, and the crystal phase composition of the cesium tungsten bronze powder is Cs _0.2 WO ₃ or Cs _0.32 WO ₃ , the powder particle size is 100-1300nm, and the specific surface area is 7-50m ² /g; the film-forming agent is polyvinyl butyral (PVB), polyvinyl alcohol (PVA) or collodion ). Among them, polyvinyl alcohol (PVA) is preferred.

More specifically, the above-mentioned coating preparation method of the present invention comprises the following steps:

① Prepare slurry I with a PVA content of 0.05-0.15 g/ml using water or an aqueous citric acid solution with a concentration of 1-4 mol/L as a solvent;

②Cesium tungsten bronze powder is ground in water or citric acid aqueous solution with a concentration of 2mol/L, and ultrasonically dispersed to obtain slurry II;

③Add the slurry II to the slurry I according to the volume ratio of 1:3~1:1, so that the content of cesium tungsten bronze powder is 0.0135~0.05g/ml, and then stir and heat the mixture in a water bath at 80°C for 30min. Place it for another 2 days to obtain a transparent heat-insulating coating for glass.

The slurry I described in the above coating preparation method of the present invention also contains a defoamer. Those skilled in the art can routinely determine the specific type and dosage of the defoamer according to the prior art, and the present invention uses SN-DEFOAMER1340 defoamer.

In the above-mentioned coating preparation method of the present invention, the preparation method of slurry I is: soak polyvinyl alcohol (PVA) in water or the citric acid aqueous solution that concentration is 1～4mol/L for 1～3h, add defoamer, then The mixture was heated and stirred in a water bath at 95° C. for 1 to 3 hours, and the slurry I was obtained after filtration, wherein the PVA content was 0.05 g/ml to 0.15 g/ml.

In the above coating preparation method of the present invention, the solvent used in the step ① and step ② is preferably water.

Most preferably, the preparation method of glass surface transparent thermal insulation coating of the present invention comprises the steps:

① Soak polyvinyl alcohol (PVA) in water for 1-3 hours, add SN-DEFOAMER 1340 defoamer, then heat and stir the mixture in a 95°C water bath for 1-3 hours, and obtain slurry I after filtration, in which the PVA content is 0.05g/ml～0.15g/ml;

②Grind cesium tungsten bronze powder in water for 5 minutes, then ultrasonically disperse it for 20 minutes, repeat the operation of grinding and ultrasonic dispersion until uniform and stable cesium tungsten bronze slurry II is obtained;

③Add the slurry II to the slurry I according to the volume ratio of 1:3~1:1, so that the content of cesium tungsten bronze powder is 0.0135~0.05g/ml, and then stir and heat the mixture in a water bath at 80°C for 30min. Place it for another 2 days to obtain a transparent heat-insulating coating for glass.

The glass transparent heat-insulating coating of the present invention contains a new type of near-infrared shielding particles—cesium tungsten bronze (Cs _x WO ₃ ) nanopowder. Adjustment function, that is, with the extension of light intensity and light time, the visible light transmission and near-infrared shielding effect will be further enhanced, so it is especially suitable for preparing transparent heat insulation film on the glass surface. It is an intelligent glass transparent heat insulation film. Coatings have broad application prospects in the fields of thermal insulation of architectural window glass and automotive glass. The coating is composed of film-forming agents such as polyvinyl alcohol (PVA), has simple components, and is suitable for large-scale industrial production and practical application.

Description of drawings

8 pieces of accompanying drawings of the present invention:

Figures 1-6 are the UV-visible transmission spectra of the glass coated with the transparent heat-insulating coating on the glass surface prepared in Examples 1-6 before and after UV irradiation.

Fig. 7 is the heat insulation test results of the glass coated with the coatings prepared in Examples 1-4 and the blank glass.

Fig. 8 is the heat insulation test results of the glass coated with the coating prepared in Examples 5-6 and the blank glass.

Detailed ways

The invention provides a novel transparent heat-insulating coating for glass surfaces and a preparation method thereof. The coating contains cesium tungsten bronze powder with a general formula of Cs _0.1-3.5 WO ₃ , the crystal phase composition of the powder is Cs _0.2 WO ₃ or Cs _0.32 WO ₃ , the particle size of the powder is 100-1300 nm, and the specific surface area is 7-50m ² /g. The preparation method of the coating includes the step of mixing the above-mentioned cesium tungsten bronze powder with a film-forming agent, polyvinyl butyral (PVB), polyvinyl alcohol (PVA) or collodion. The cesium tungsten bronze powder described in the present invention is prepared by the following method:

① Prepare a precursor solution containing tungstic acid, cesium carbonate and reducing substances according to the Cs/W molar ratio of 0.01 to 0.35:1, and the solvent is water or a mixture of ethanol and water in a volume ratio of 1:4 to 4:1;

②The precursor solution is placed in an autoclave, reacted at 180-200°C for 1-3 days, and the resulting precipitate is post-processed to obtain cesium tungsten bronze powder.

In the above method for preparing cesium tungsten bronze powder, the concentration of tungstic acid in the precursor solution is 0.1-1.0 mol/L.

The reducing substance described in the above method for preparing cesium tungsten bronze powder is citric acid. The concentration of citric acid in the precursor solution is 0.1-1.5 mol/L.

The following method can be used to prepare the precursor solution: under stirring conditions, add 0.1-1.0 mol/L cesium carbonate aqueous solution to 0.1-1.0 mol/L tungstic acid aqueous solution, then add citric acid, make up the solvent and continue stirring for 1- 2h. In the above technical solution, it is preferable to use water as the precursor solution, and the particle size of the prepared Cs _x WO ₃ powder is slightly smaller.

The preparation method of tungstic acid aqueous solution in the method for preparing cesium tungsten bronze powder mentioned above is to dissolve sodium tungstate in deionized water to prepare sodium tungstate aqueous solution, and then exchange the sodium tungstate aqueous solution through styrene cation exchange resin to obtain tungstic acid Solution, make the concentration of tungstic acid solution be 0.1～1.0mol/L.

The step of preparing the precursor solution in the above-mentioned method for preparing cesium tungsten bronze powder may be to add simple substance of citric acid or an aqueous solution of citric acid with a concentration of 1-5 mol/L. The latter is preferred.

In the above method for preparing cesium tungsten bronze powder, the post-treatment of the obtained precipitate in step ② includes the steps of water washing, alcohol washing, centrifugation, and vacuum or sub-vacuum drying. The sub-vacuum mentioned therein is a vacuum degree of 0.09MPa, which can be obtained by the following method: put the precipitated product sample obtained by centrifugation into an Erlenmeyer flask, seal the Erlenmeyer flask with a rubber stopper with a hole, and connect the vacuum pump to the rubber stopper , vacuumize the conical flask, keep the vacuum degree at 0.09MPa, then put the conical flask into a water bath at 50-80°C, and the sample can be dried in sub-vacuum.

More specifically, the above-mentioned method for preparing cesium tungsten bronze powder includes the following steps:

① Prepare tungstic acid aqueous solution, cesium carbonate aqueous solution and citric acid solution respectively;

Preparation of tungstic acid aqueous solution: According to the concentration of tungstic acid solution to be prepared, accurately weigh a certain amount of sodium tungstate, dissolve it in deionized water to obtain an aqueous solution of sodium tungstate, and then exchange the aqueous solution of sodium tungstate through styrene cation exchange resin Finally, an aqueous tungstic acid solution is obtained, and the concentration of the obtained aqueous tungstic acid solution is 0.1 to 1.0 mol/L;

Preparation of citric acid solution: weigh citric acid and dissolve it in deionized water to obtain a citric acid solution with a concentration of 1-5mol/L;

Preparation of cesium carbonate aqueous solution: according to the concentration of cesium carbonate aqueous solution to be prepared, accurately weigh a certain amount of cesium carbonate, dissolve it in deionized water, and obtain cesium carbonate aqueous solution, the concentration of cesium carbonate aqueous solution is 0.1～1.0mol/L;

② Preparation of precursor solution: While stirring, add cesium carbonate aqueous solution to tungstic acid aqueous solution, then add citric acid solution, and then add a certain amount of absolute ethanol (or no ethanol) and continue stirring for 1 to 2 hours to obtain the prepared cesium Tungsten bronze reaction precursor solution;

③Transfer the precursor solution into an autoclave, react at 180-200°C for 1-3 days, wash with water, wash with alcohol, and centrifuge to obtain a precipitated sample of Cs _x WO ₃ , and dry it under vacuum or sub-vacuum at 50-80°C After that, cesium tungsten bronze (Cs _x WO ₃ ) powder was obtained.

Unless otherwise specified, the following methods are used for the determination of performance parameters of cesium tungsten bronze (Cs _x WO ₃ ) powder and coating products prepared by the above method:

(1) Use D/max-3B X-ray diffraction (X-ray diffraction, XRD) to analyze the crystal phase composition of the synthesized Cs _x WO ₃ powder, using Cu Kα rays, tube pressure 40.0kV, current 20mA, scanning The range is 5°～70°.

(2) The SSA-4200 pore size and specific surface area analyzer produced by Biod Electronic Technology Co., Ltd. was used to characterize the specific surface area of Cs _x WO ₃ powder, and the adsorption gas was N ₂ .

(3) Use the Zetasize 3000HSA laser particle size analyzer produced by British MALVERN Instruments to characterize the particle size distribution and average particle size of the Cs _x WO ₃ powder. Specific test method: Disperse the prepared powder in water, test its particle size distribution and average particle size directly after ultrasonication for 5 minutes; or disperse 0.272g of Cs _x WO ₃ powder in 1g/10ml of Prepare a uniform slurry in the PVA solution, then disperse the Cs _x WO ₃ /PVA slurry in water, test the average particle size of the Cs _x WO ₃ particles in the slurry after ultrasonication for 5 minutes.

(4) The ultraviolet-visible-near-infrared absorption properties of the Cs _x WO ₃ powder were characterized in the range of 300-1100 nm by using a Lambda35 ultraviolet-visible spectrophotometer produced in the United States. Specific test method: With BaCl ₂ as the background, the powder is pressed on the BaCl ₂ sheet, and the near-infrared absorption performance is characterized by testing its absorbance.

(5) Preparation of transparent film on glass surface:

Pour a certain amount of thermal insulation paint on the glass slide, use a glass rod to spread the paint evenly on the glass slide, and then quickly pull one end of the glass slide vertically to make the excess paint flow out under the action of gravity. Keep the vertical state for 1 hour, and a transparent heat-insulating film on the glass surface with certain transparency, uniformity and flatness can be obtained.

Coating on ordinary large-sized glass pieces: Put ordinary glass on a fixed plane, and then use transparent tape to paste it on the two long edges of the rectangular ordinary glass piece and on the fixed plane to fix the ordinary glass. Ordinary glass surface forms a groove with scotch tape as protrusions on both sides. Pipette a certain amount of emulsion slurry at one end of the groove with a rubber dropper, and roll the emulsion slurry onto the surface of the glass sheet with a clean glass rod, thereby forming a film of a certain thickness on the glass surface.

(6) Utilize the Lambda35 UV-visible spectrophotometer produced in the United States to characterize the UV-visible-near-infrared transmission spectrum of the glass surface coating film in the range of 300-1100 nm, so as to evaluate the visible light transmission and near-infrared shielding performance of the glass surface film .

(7) Test of photochromic or near-infrared shading light self-adjusting intelligent function: test the transmission of the sample again after irradiating the glass sheet coated with Cs _x WO ₃ film for 10min, 30min and other times with ultraviolet light (275nm) Spectrum, in order to evaluate the relationship between the photochromic performance and near-infrared shielding performance of the glass surface film with the light time.

(8) Test of thermal insulation performance of glass film samples: prepare thermal insulation space with foam board, design thermal insulation space size is 5×10×10.5 (cm ³ ), common glass sheet area is 7×12 (cm ² ), coated The membrane area is 6.4×11 (cm ² ); the bottom of the box is covered with a black iron plate, and the red water thermometer (100°C) is closely attached to the surface of the black iron plate.

Test process: Put the glass coated with heat-insulating paint on the window of the heat-insulating airtight space, let the part coated with the film completely cover the window of the space, irradiate it with a 250W infrared lamp at a vertical distance of 25cm from the window, and record the reading of the thermometer Variation with exposure time. Use the same method to test the temperature change with time when the blank glass sheet is used as a window, and compare the two to obtain the heat insulation effect of the heat insulation coating.

The technical solutions of the present invention will be further described below in the form of specific examples, without limiting the content of the present invention in any way.

Example 1

① Prepare Cs _0.3 WO ₃ powder with Cs/W (molar ratio)=0.3:1.

Weigh a certain amount of sodium tungstate, dissolve it in deionized water, and prepare a 0.5mol/L sodium tungstate solution, and use styrene cation exchange resin to ion-exchange the sodium tungstate solution to obtain 0.5mol/L tungstic acid solution; measure 20ml of 0.5mol/L tungstic acid solution, put it into a beaker, add 30ml of 2mol/L citric acid solution once during stirring, slowly add 5ml of 0.3mol/L cesium carbonate solution dropwise, and continue stirring for 1h. Obtain the reaction precursor solution for preparing Cs _0.3 WO ₃ powder; transfer the above-prepared reaction precursor solution into an autoclave, and conduct a continuous hydrothermal reaction at 200°C for 3 days; wash the reacted precipitate with water and alcohol for 3 days Once, after centrifugation, dry in a sub-vacuum at 50°C for 10 hours to obtain blue Cs _0.3 WO ₃ powder.

②Preparation of polyvinyl alcohol (PVA) solution: Soak 10g of polyvinyl alcohol (PVA) in 2mol/L, 100ml of citric acid for 2h, add 4 drops of defoamer dropwise, then heat and stir in a water bath at 95°C for 1h, after filtering A transparent polyvinyl alcohol (PVA) slurry with considerable viscosity is obtained.

③ Preparation of glass transparent heat-insulating coating: Weigh 0.272g of cesium tungsten bronze powder, fully grind it in 2mol/L, 10ml citric acid for 5min, then ultrasonically disperse it for 20min, repeat grinding like this, and ultrasonically 3 times to get a uniform slurry; Then add it to 10ml of prepared PVA slurry, stir and heat it in a water bath at 80°C for 30 minutes, and then leave it for 2 days to obtain the glass transparent heat-insulating coating to be coated.

It has been determined that the crystal phase of the Cs _0.3 WO ₃ powder is hexagonal Cs _0.32 WO ₃ , and when it is dispersed in deionized water, the measured average particle size is 188.5nm and the specific surface area is 41.67m ² /g; Meter test results: the glass sample coated with Cs _0.3 WO ₃ transparent thermal insulation coating has the highest light transmittance at 799nm wavelength of visible light, which is 62%; the lowest light transmittance at 1100nm wavelength in the near infrared region is 49% %, compared with the highest transmittance in the visible region, the transmittance at 1100nm in the near-infrared region has dropped

Test results of photochromic or near-infrared shading light self-adjusting intelligent function: after 30 minutes of ultraviolet light, visible light at 607nm wavelength has the highest light transmittance of 56%; it has the lowest light transmittance at 1100nm wavelength in the near-infrared region of 780nm to 1100nm The light transmittance is 29%. Compared with the highest transmittance in the visible light region, the transmittance in the near infrared 1100nm has dropped

Heat insulation test results: After being irradiated by infrared light for 20 minutes, the temperature displayed in the heat insulation space of the blank glass (uncoated sample) is 80°C, and the temperature displayed in the heat insulation space of the coated glass sample is 54.8°C, with a temperature difference of 25.2°C; After 30 minutes, the temperature displayed in the insulation space of the blank glass (uncoated sample) was 86.8°C, and the temperature displayed in the insulation space of the coated glass sample was 66.2°C, with a temperature difference of 24.6°C. After 54 minutes, the temperature difference remained at 24.8°C.

Example 2

① Prepare Cs _0.3 WO ₃ powder with Cs/W (molar ratio)=0.3:1.

Weigh a certain amount of sodium tungstate, dissolve it in deionized water, and prepare a 0.5mol/L sodium tungstate solution, and use styrene cation exchange resin to ion-exchange the sodium tungstate solution to obtain 0.5mol/L tungstic acid solution; measure 20ml of 0.5mol/L tungstic acid solution, put it into a beaker, add 12.6g of citric acid once during stirring, after stirring evenly, slowly add 5ml of 0.3mol/L cesium carbonate solution dropwise, and then add 10ml Absolute ethanol and 20ml of deionized water, continue to stir for 1h to obtain the reaction precursor solution for preparing Cs _0.3 WO ₃ powder; transfer the reaction precursor solution prepared above into an autoclave, and conduct a continuous hydrothermal reaction at 190°C for 3d; The reacted precipitate was washed with water and alcohol three times in sequence, and after centrifugation, it was dried in a sub-vacuum at 50°C for 10 hours to obtain light blue Cs _0.3 WO ₃ powder.

② Polyvinyl alcohol (PVA) solution preparation:

Soak 10g of polyvinyl alcohol PVA in 100ml of deionized water for 2 hours at room temperature, add 4 drops of defoamer dropwise, then heat and stir in a water bath at 95°C for 2.5 hours, and filter through a 200-mesh sieve to obtain a white, slightly transparent, quite Viscosity of PVA slurry.

③Preparation of glass transparent heat-insulating coating: Fully grind 0.272g of cesium tungsten bronze powder in 5ml of deionized water for 5min, then ultrasonically disperse for 20min, repeat grinding in this way, and ultrasonically 3 times to obtain uniform and stable cesium tungsten bronze (Cs _x WO ₃ ) slurry; then the obtained cesium tungsten bronze (Cs _x WO ₃ ) slurry was added to the 15ml PVA slurry obtained in step ②, stirred and heated in a water bath at 80°C for 30min, and left for 2d to obtain the Coated glass with transparent thermal insulation coating.

It has been determined that the crystal phase of the Cs _0.3 WO ₃ powder is hexagonal Cs _0.32 WO ₃ , which is dispersed in an aqueous solution of polyvinyl alcohol (polyvinyl alcohol concentration 1g/10ml), the measured average particle size is 1270nm, and the specific surface area is 28.47m ² /g; UV-visible spectrophotometer test results: the glass sample coated with Cs _0.3 WO ₃ transparent heat-insulating coating has the highest light transmittance at 785nm wavelength of visible light, which is 50%; in the near infrared region 1100nm wavelength has the lowest light transmittance at 45%, compared with the highest transmittance in the visible region, the transmittance at 1100nm in the near infrared region has dropped $\▿T(\%)=5\%.$

Test results of photochromic or near-infrared shading light self-adjusting intelligent function: After 30 minutes of ultraviolet light, the visible light at 712nm wavelength has the highest light transmittance of 50%; it has the lowest at 1100nm wavelength in the near-infrared region of 780nm to 1100nm The light transmittance is 37%. Compared with the highest transmittance in the visible light region, the transmittance in the near infrared 1100nm has dropped

Heat insulation test results: After being irradiated by infrared light for 20 minutes, the temperature displayed in the heat insulation space of the blank glass (uncoated sample) is 80°C, and the temperature displayed in the heat insulation space of the coated glass sample is 65°C, with a temperature difference of 15°C; After 30 minutes, the temperature displayed in the insulation space of the blank glass (uncoated sample) was 86.8°C, and the temperature displayed in the insulation space of the coated glass sample was 72.8°C, with a temperature difference of 14°C. After 42 minutes, the temperature difference remained at 14°C.

Example 3

① Prepare Cs _0.3 WO ₃ powder with Cs/W (molar ratio)=0.3:1.

Weigh a certain amount of sodium tungstate, dissolve it in deionized water, and prepare a 0.5mol/L sodium tungstate solution, and use styrene cation exchange resin to ion-exchange the sodium tungstate solution to obtain 0.5mol/L tungstic acid solution; measure 20ml of 0.5mol/L tungstic acid solution, put it into a beaker, add 12.6g of citric acid once during stirring, after stirring evenly, slowly add 5ml of 0.3mol/L cesium carbonate solution dropwise, and then add 30ml Continue stirring with absolute ethanol for 1 hour to obtain a reaction precursor solution for preparing Cs _0.3 WO ₃ powder; transfer the reaction precursor solution prepared above into an autoclave, and conduct a continuous hydrothermal reaction at 190°C for 3 days; The mixture was washed with water and alcohol three times in sequence, and after centrifugation, it was dried in a sub-vacuum at 50°C for 10 hours to obtain light blue Cs _0.3 WO ₃ powder.

2. polyvinyl alcohol (PVA) solution preparation: with embodiment 2 steps 2.;

③ glass transparent heat-insulating coating preparation: the same as embodiment 2 step ③;

It has been determined that the crystal phase of the Cs _0.3 WO ₃ powder is hexagonal Cs _0.32 WO ₃ , which is dispersed in an aqueous solution of polyvinyl alcohol (polyvinyl alcohol concentration 1g/10ml), the measured average particle size is 1032nm, and the specific surface area is 27.44nm; UV-visible spectrophotometer test results: After the glass sample coated with Cs _0.3 WO ₃ transparent heat-insulating coating is exposed to the outside for 10 minutes, it has the highest light transmittance at 877nm wavelength of visible light, which is 39%; The 1100nm near-infrared region has the lowest light transmittance of 36%. Compared with the highest transmittance in the visible region, the transmittance at 1100nm in the near-infrared region has decreased

Photochromic or near-infrared shading light self-adjusting intelligent function test results: After 30 minutes of ultraviolet light, visible light at 737nm wavelength has the highest light transmittance of 37%; in the near-infrared region of 780nm to 1100nm, 1100nm wavelength has the lowest The light transmittance is 25%. Compared with the highest transmittance in the visible light region, the transmittance in the near infrared 1100nm has decreased

Heat insulation test results: After being irradiated by infrared light for 20 minutes, the temperature displayed in the heat insulation space of the blank glass (uncoated sample) is 80°C, and the temperature displayed in the heat insulation space of the coated glass sample is 59.8°C, with a temperature difference of 21.2°C; After 30 minutes, the blank glass (uncoated sample) showed a temperature of 86.8°C in the heat-insulated space, and the coated glass sample showed a temperature of 66.5°C in the heat-insulated space, with a temperature difference of 20.3°C. After 50 minutes, the temperature difference remained at 20.6°C.

Example 4

① Prepare Cs _0.3 WO ₃ powder with Cs/W (molar ratio)=0.3:1.

Weigh a certain amount of sodium tungstate, dissolve it in deionized water, and prepare a 0.5mol/L sodium tungstate solution, and use styrene cation exchange resin to ion-exchange the sodium tungstate solution to obtain 0.5mol/L tungstic acid solution; measure 10ml of 0.5mol/L tungstic acid solution, put it into a beaker, add 12.6g of citric acid once during stirring, after stirring evenly, slowly add 5ml of 0.15mol/L cesium carbonate solution dropwise, and then add 40ml Continue stirring with absolute ethanol for 1 hour to obtain a reaction precursor solution for preparing Cs _0.3 WO ₃ powder; transfer the reaction precursor solution prepared above into an autoclave, and conduct a continuous hydrothermal reaction at 190°C for 3 days; The mixture was washed with water and alcohol three times in sequence, and after centrifugation, it was dried in a sub-vacuum at 50°C for 10 hours to obtain light blue Cs _0.3 WO ₃ powder.

2. polyvinyl alcohol (PVA) solution preparation: with embodiment 2 steps 2.;

③ glass transparent heat-insulating coating preparation: the same as embodiment 2 step ③;

It has been determined that the crystal phase of the Cs _0.3 WO ₃ powder is hexagonal Cs _0.32 WO ₃ , which is dispersed in an aqueous solution of polyvinyl alcohol (polyvinyl alcohol concentration 1g/10ml), the measured average particle size is 561nm, and the specific surface area is 25.65m ² /g; UV-visible spectrophotometer test results: the glass sample coated with Cs _0.3 WO ₃ transparent heat-insulating coating has the highest light transmittance at 716nm wavelength of visible light, which is 56%; The wavelength of 1100nm in the region has the lowest light transmittance of 50%. Compared with the highest transmittance in the visible region, the transmittance of 1100nm in the near-infrared region has decreased. $\▿T(\%)=6\%.$

Test results of photochromic or near-infrared shading light self-adjusting intelligent function: After 30 minutes of ultraviolet light, the visible light at 676nm wavelength has the highest light transmittance of 54%; it has the lowest at 1100nm wavelength in the near-infrared region of 780nm to 1100nm The light transmittance is 40.5%. Compared with the highest transmittance in the visible light region, the transmittance in the near infrared 1100nm has dropped

Heat insulation test results: After being irradiated by infrared light for 20 minutes, the temperature displayed in the heat insulation space of the blank glass (uncoated sample) is 80°C, and the temperature displayed in the heat insulation space of the coated glass sample is 66.5°C, with a temperature difference of 13.5°C; After 30 minutes, the temperature displayed in the insulation space of the blank glass (uncoated sample) was 86.8°C, and the temperature displayed in the insulation space of the coated glass sample was 73.5°C, with a temperature difference of 14°C. After 30 minutes, the temperature difference remained at 13.3°C. After 50 minutes, the temperature difference remained constant. at 12.8°C.

Example 5

① Prepare Cs _0.35 WO ₃ powder with Cs/W (molar ratio)=0.35:1.

Weigh a certain amount of sodium tungstate, dissolve it in deionized water, and prepare a 0.5mol/L sodium tungstate solution, and use styrene cation exchange resin to ion-exchange the sodium tungstate solution to obtain 0.5mol/L tungstic acid solution; measure 60ml of 0.5mol/L tungstic acid solution, put it into a beaker, add 37.8g of citric acid once during stirring, after stirring evenly, slowly add 15ml of 0.35mol/L cesium carbonate solution dropwise, and then add 90ml With absolute ethanol, continue to stir for 1 hour to obtain a reaction precursor solution for preparing Cs _0.35 WO ₃ powder; transfer the reaction precursor solution prepared above into three 100ml autoclaves in three groups, and conduct a continuous hydrothermal reaction at 190°C for 3 days ; The precipitate after the reaction was washed with water and alcohol for 3 times in sequence, and after centrifugation, it was dried in a sub-vacuum at 50°C for 10 hours to obtain light blue Cs _0.35 WO ₃ powder.

②Preparation of polyvinyl alcohol (PVA) solution: Weigh 10g of PVA, soak it in 100ml deionized water for 2 hours at room temperature, then add 4 drops of defoamer dropwise, stir in a water bath at 80°C for 2 hours, and then filter through a 200-mesh sieve to obtain 1g/10ml PVA aqueous solution with a certain viscosity;

③ glass transparent heat-insulating coating preparation: the same as embodiment 2 step ③;

It has been determined that the crystal phase of the Cs _0.35 WO ₃ powder is hexagonal Cs _0.32 WO ₃ , which is dispersed in an aqueous solution of polyvinyl alcohol (polyvinyl alcohol concentration 1g/10ml), the measured average particle size is 520nm, and the specific surface area is 7.41m ² /g; UV-visible spectrophotometer test results: the glass sample coated with Cs _0.3 WO ₃ transparent heat-insulating coating has the highest light transmittance at 681nm wavelength of visible light, which is 50.4%; It has the lowest light transmittance at 1100nm wavelength, which is 34.2%. Compared with the highest transmittance in the visible light region, the transmittance at 1100nm in the near infrared region has decreased. $\▿T(\%)=16.2\%.$

Photochromic or near-infrared shading light self-adjusting intelligent function test results: After 30 minutes of ultraviolet light, the visible light at 659nm wavelength has the highest light transmittance of 48.7%; it has the lowest at 1100nm wavelength in the near-infrared region of 780nm to 1100nm The light transmittance is 30.4%. Compared with the highest transmittance in the visible light region, the transmittance in the near infrared 1100nm has dropped

Heat insulation test results: After being irradiated by infrared light for 20 minutes, the temperature displayed in the heat insulation space of the blank glass (uncoated sample) is 78°C, and the temperature displayed in the heat insulation space of the coated glass sample is 61°C, with a temperature difference of 17°C; After 30 minutes, the temperature displayed in the insulation space of the blank glass (uncoated sample) was 84.8°C, and the temperature displayed in the insulation space of the coated glass sample was 68.5°C, with a temperature difference of 16.3°C. After 64 minutes, the temperature difference remained at 15°C.

Example 6

① Prepare Cs _0.1 WO ₃ powder with Cs/W (molar ratio)=0.1:1.

Weigh a certain amount of sodium tungstate, dissolve it in deionized water, and prepare a 0.5mol/L sodium tungstate solution, and use styrene cation exchange resin to ion-exchange the sodium tungstate solution to obtain 0.5mol/L tungstic acid solution; measure 60ml of 0.5mol/L tungstic acid solution, put it into a beaker, add 37.8g of citric acid once during stirring, after stirring evenly, slowly add 15ml of 0.1mol/L cesium carbonate solution dropwise, and then add 90ml Continue stirring with absolute ethanol for 1 hour to obtain a reaction precursor solution for preparing Cs _0.1 WO ₃ powder; transfer the reaction precursor solution prepared above into three 100ml autoclaves in three groups, and conduct a continuous hydrothermal reaction at 190°C for 3 days ; Wash the reacted precipitate with water and alcohol three times in sequence, after centrifugation, dry at 50° C. for 10 h in a sub-vacuum to obtain light blue Cs _0.1 WO ₃ powder.

2. polyvinyl alcohol (PVA) solution preparation: with embodiment 5 steps 2.;

③ glass transparent heat-insulating coating preparation: the same as embodiment 2 step ③;

It has been determined that the crystal phase of the Cs _0.1 WO ₃ powder is hexagonal Cs _0.2 WO ₃ , which is dispersed in an aqueous solution of polyvinyl alcohol (polyvinyl alcohol concentration 1g/10ml), the measured average particle size is 566nm, and the specific surface area is 43.2 m ² /g; UV-visible spectrophotometer test results: the glass sample coated with Cs _0.1 WO ₃ transparent thermal insulation coating has the highest light transmittance at 674nm wavelength of visible light, which is 62.6%; in the near-infrared region of 780-1100nm The 1100nm wavelength has the lowest light transmittance of 49%. Compared with the highest transmittance in the visible light region, the transmittance at 1100nm in the near infrared region has dropped $\▿T(\%)=13.6\%.$

Photochromic or near-infrared shading light self-adjustment intelligent function test results: After 30 minutes of ultraviolet light, visible light at 666nm wavelength has the highest light transmittance of 61.8%; it has the lowest light transmittance at 1100nm wavelength in the near-infrared region of 780nm to 1100nm The light transmittance is 46.5%. Compared with the highest transmittance in the visible light region, the transmittance in the near infrared 1100nm has dropped

Heat insulation test results: After being irradiated by infrared light for 20 minutes, the temperature displayed in the heat insulation space of the blank glass (uncoated sample) is 78°C, and the temperature displayed in the heat insulation space of the coated glass sample is 70°C, with a temperature difference of 8°C; After 30 minutes, the temperature displayed in the insulation space of the blank glass (uncoated sample) was 84.8°C, and the temperature displayed in the insulation space of the coated glass sample was 78°C, with a temperature difference of 6.8°C.

Claims (10)

1. glass transparent insulating coating, it is characterized in that containing in this coating general formula is Cs _0.1-3.5WO ₃Caesium tungsten bronze(s) powder, described powder crystalline phase consists of Cs _0.2WO ₃Or Cs _0.32WO ₃, powder size is that 100～1300nm, specific surface area are 7～50m ²/ g.

2. the described glass transparent insulating coating of claim 1, the content that it is characterized in that caesium tungsten bronze(s) powder in the described coating is 0.0135～0.05g/ml.

3. the described glass transparent insulating coating of claim 2 is characterized in that also containing in the described coating polyvinyl butyral acetal, polyvinyl alcohol or pyroxylin (e) cement as membrane-forming agent.

4. the preparation method of the described glass transparent insulating coating of claim 1 is characterized in that comprising with caesium tungsten bronze(s) powder and membrane-forming agent blended step, wherein:

Described caesium tungsten bronze(s) powder crystalline phase consists of Cs _0.2WO ₃Or Cs _0.32WO ₃, powder size is that 100～1300nm, specific surface area are 7～50m ²/ g;

Described membrane-forming agent is polyvinyl butyral acetal, polyvinyl alcohol or pyroxylin (e) cement.

5. the described method of claim 4 is characterized in that described membrane-forming agent is a polyvinyl alcohol.

6. the described method of claim 5 comprises the steps:

1. be that the aqueous citric acid solution of 1～4mol/L is that solvent prepares the slurry I that PVA content is 0.05～0.15g/ml with water or concentration;

2. caesium tungsten bronze(s) powder is grinding, a ultra-sonic dispersion in the 2mol/L aqueous citric acid solution at water or concentration, gets slurry II;

3. according to volume ratio 1: 3～1: 1 slurry II is joined among the slurry I, makes wherein that caesium tungsten bronze(s) powder content is 0.0135～0.05g/ml, then with mixture at 80 ℃ of stirred in water bath heating 30min, placed again 2 days, glass transparent insulating coating.

7. the described method of claim 6 is characterized in that also containing defoamer among the described slurry I.

8. the described method of claim 7, the preparation method who it is characterized in that described slurry I is: polyvinyl alcohol is soaked in 1～3h in the aqueous citric acid solution that water or concentration are 1～4mol/L, add defoamer, then with mixture heated and stirred 1～3h in 95 ℃ of water-baths, obtain slurry I after filtering, wherein PVA content is 0.05g/ml～0.15g/ml.

9. arbitrary described method in the claim 6～8, it is characterized in that described step 1. with step 2. in employed solvent be water.

10. the described method of claim 9 is characterized in that comprising the steps:

1. polyvinyl alcohol is soaked in 1～3h in the water, adds SN-DEFOAMER 1340 defoamers, with mixture heated and stirred 1～3h in 95 ℃ of water-baths, obtain slurry I after filtering then, wherein PVA content is 0.05g/ml～0.15g/ml;

2. caesium tungsten bronze(s) powder grinds ultra-sonic dispersion 20min behind the 5min in water, repeats to grind the operation with ultra-sonic dispersion, until obtaining even, stable caesium tungsten bronze(s) slurry II;

3. according to volume ratio 1: 3～1: 1 slurry II is joined among the slurry I, makes wherein that caesium tungsten bronze(s) powder content is 0.0135～0.05g/ml, then with mixture at 80 ℃ of stirred in water bath heating 30min, placed again 2 days, glass transparent insulating coating.

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