Anti-reflective and anti-reflective glass and its preparation method
By forming a porous wax layer on a photovoltaic glass substrate and etching micropores, the problems of hardness and wear resistance in the coating process are solved, achieving a high transmittance effect at low cost.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- LONGI GREEN ENERGY TECH CO LTD
- Filing Date
- 2022-07-22
- Publication Date
- 2026-07-03
AI Technical Summary
Existing photovoltaic glass coatings have low hardness and poor wear resistance, and the coating is easy to peel off. In addition, photolithography technology is expensive, which affects the light transmittance and cost of photovoltaic modules.
Antireflective and anti-reflective glass was prepared by forming a porous wax layer on the surface of a glass substrate using a paraffin dispersion and then etching to create a microporous structure.
It reduces the reflectivity of the glass, increases the transmittance, and is simple to operate and has a low cost.
Smart Images
Figure CN117466541B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of glass surface treatment technology, specifically to an anti-reflective and anti-reflective glass and its preparation method. Background Technology
[0002] In recent years, with the global consensus on addressing climate change and the formulation of carbon reduction targets by major economies, improving the cost-effectiveness of photovoltaic (PV) modules to further enhance their competitive advantage over other energy sources is of great practical significance for the healthy and sustainable development of the PV market and the achievement of carbon reduction goals. Improving the cost-effectiveness of PV modules can be achieved in two ways: firstly, by reducing material costs and optimizing various production processes to lower module costs; and secondly, by improving the photoelectric conversion performance of the modules. Compared to the former, which already has sufficiently low raw material costs and mature processes, the latter offers greater potential and more opportunities. Among these, the encapsulation of PV cells is a crucial step, and the light transmittance of PV glass is one of the important factors affecting the photoelectric conversion efficiency of PV modules.
[0003] Currently, many methods exist for achieving anti-reflection and anti-transmittance in glass, with surface coating being the most common. This involves coating the glass surface with one or more layers of metal, metal compounds, or organic thin films to reduce light reflection and improve the transmittance of photovoltaic glass. However, after coating, most functional films have lower hardness than glass, resulting in poor wear resistance. Furthermore, due to the significant difference in composition between the film material and the glass, the interfacial adhesion is low. Consequently, under prolonged exposure to humid, hot, freezing, ultraviolet radiation, and salt spray environments, the transmittance of this coated glass decreases, and phenomena such as rainbow-like patterns appear on the surface. The film is also prone to peeling off. While photolithography can avoid these problems by creating light-trapping structures on the glass surface, the tools used in photolithography are expensive, significantly increasing the cost of photovoltaic modules. Summary of the Invention
[0004] The purpose of this disclosure is to provide an anti-reflective and anti-reflective glass and its preparation method. This method can produce an anti-reflective and anti-reflective glass with multiple micropores distributed on its surface, which can effectively reduce the reflectivity of the glass surface and increase the transmittance.
[0005] To achieve the above objectives, the first aspect of this disclosure provides a method for preparing antireflective and antireflective glass, the method comprising:
[0006] Paraffin wax is dispersed in an organic solvent to obtain a paraffin wax dispersion. The paraffin wax dispersion is coated on the main surface of a glass substrate, and then the organic solvent is removed to obtain a glass substrate with a porous wax layer on the surface. The paraffin wax concentration in the paraffin wax dispersion is 0.01 to 0.03 g / mL.
[0007] An etchant is used to etch the glass substrate with a porous wax layer on its surface, and the porous wax layer is removed after etching is completed.
[0008] Optionally, the paraffin wax has a melting point of 50–70°C and contains hydrocarbons with 18–30 carbon atoms; the organic solvent includes polar solvents and / or nonpolar solvents, wherein the polar solvent is selected from one or more of alcohols with 1–4 carbon atoms, ethers with 2–4 carbon atoms, and ketones with 2–4 carbon atoms, preferably one or more of ethanol, isopropanol, and acetone; the nonpolar solvent is selected from one or more of gasoline, carbon disulfide, xylene, benzene, chloroform, carbon tetrachloride, and naphtha; preferably, the paraffin wax is dispersed in a polar organic solvent and heated to 50–75°C to obtain the paraffin wax dispersion; the thickness of the porous wax layer is 0.5–2 μm.
[0009] Optionally, the etching agent is an inorganic acid solution, including a hydrofluoric acid solution, wherein the hydrofluoric acid content in the hydrofluoric acid solution is 4-12% by weight; optionally, the inorganic acid solution also includes hydrochloric acid and / or nitric acid; the etching temperature is 15-30°C, and the etching time is 10-30 min.
[0010] Optionally, the method further includes: forming a colloidal protective layer on the main surface of the glass substrate away from the porous wax layer before etching, and removing the colloidal protective layer after etching is completed.
[0011] Optionally, the method further includes pretreating the glass substrate before coating the paraffin dispersion, the pretreatment including chemical cleaning and / or ultrasonic cleaning of the surface of the glass substrate.
[0012] Optionally, the coating method includes one or more of spraying, spin coating, and blade coating.
[0013] Optionally, after the etching is completed, the porous wax layer is removed using an organic solvent, wherein the organic solvent is selected from one or more of ethanol, isopropanol and acetone.
[0014] The second aspect of this disclosure provides an anti-reflective and anti-reflective glass prepared by the method described in the first aspect of this disclosure, comprising a glass substrate and a plurality of micropores distributed on the surface of the glass substrate, wherein the micropores are blind pores and the average diameter of the opening of the micropores is 8 to 14 μm.
[0015] Optionally, the pore depth of the micropores is 0.2 to 0.5 μm, and the opening distance between two adjacent micropores is less than 5 μm; all the micropores are distributed on one side of the main surface of the glass substrate.
[0016] Optionally, the micropores are formed by etching at least a portion of the surface of the glass substrate.
[0017] The present disclosure provides an antireflective and anti-reflective glass and its preparation method using the above technical solution. The preparation method involves coating a paraffin dispersion with a concentration of 0.01–0.03 g / mL onto a glass substrate, removing the solvent from the paraffin dispersion, and forming a porous wax layer with a suitable pore structure on the glass substrate surface. Then, wet etching is used to selectively etch the glass substrate, resulting in an antireflective and anti-reflective glass with multiple micropores distributed on its surface. The average diameter of the openings of these micropores is in the range of 8–14 μm, resulting in a reduced reflectivity and increased transmittance of the prepared antireflective and anti-reflective glass. The method of the present disclosure is simple to operate, easy to implement, and low in cost.
[0018] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description
[0019] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:
[0020] Figure 1 This is a flowchart of the method for preparing antireflective and antireflective glass according to Embodiment 1 of this disclosure;
[0021] Figure 2 This is a schematic diagram of the structure of the antireflective and anti-reflective glass prepared according to Embodiment 1 of this disclosure;
[0022] Figure 3 The transmittance of the antireflective and anti-reflective glass 1 prepared in Embodiment 1 of this disclosure and the glass substrate;
[0023] Figure 4 The reflectance of the antireflective and anti-reflective glass 1 prepared in Embodiment 1 of this disclosure and the glass substrate. Detailed Implementation
[0024] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.
[0025] The first aspect of this disclosure provides a method for preparing antireflective and antireflective glass, the method comprising:
[0026] Paraffin wax is dispersed in an organic solvent to obtain a paraffin wax dispersion. The paraffin wax dispersion is coated on the main surface of a glass substrate, and then the organic solvent is removed to obtain a glass substrate with a porous wax layer on the surface. The paraffin wax concentration in the paraffin wax dispersion is 0.01 to 0.03 g / mL.
[0027] An etchant is used to etch the glass substrate with a porous wax layer on its surface, and the porous wax layer is removed after etching is completed.
[0028] The inventors of this disclosure discovered that coating a paraffin dispersion with a concentration of 0.01–0.03 g / mL onto a glass substrate and then removing the solvent from the paraffin dispersion can form a porous wax layer with a suitable pore structure on the glass substrate surface. Subsequently, wet etching can selectively etch the glass substrate, resulting in an antireflective and anti-reflective glass with multiple micropores distributed on its surface. The average diameter of the openings of these micropores is in the range of 8–14 μm, thus reducing the reflectivity and increasing the transmittance of the produced antireflective and anti-reflective glass. The method of this disclosure is simple to operate, easy to implement, and low in cost.
[0029] In one embodiment of this disclosure, the paraffin wax has a melting point of 50–70°C and contains hydrocarbons with 18–30 carbon atoms; the organic solvent includes polar solvents and / or nonpolar solvents, wherein the polar solvent is selected from one or more of alcohols with 1–4 carbon atoms, ethers with 2–4 carbon atoms, and ketones with 2–4 carbon atoms, preferably one or more of ethanol, isopropanol, and acetone; the nonpolar solvent is selected from one or more of gasoline, carbon disulfide, xylene, benzene, chloroform, carbon tetrachloride, and naphtha; preferably, the paraffin wax is dispersed in a polar organic solvent and heated to 50–75°C to obtain the paraffin wax dispersion. In the above embodiments, by selecting a preferred organic solvent, a paraffin dispersion of a specific concentration can be obtained. This paraffin dispersion is coated onto a glass substrate and dried at 10–40°C to allow the organic solvent to evaporate. This results in a porous wax layer with a suitable pore structure and thickness on the glass substrate surface. In a preferred embodiment, the thickness of the porous wax layer is 0.5–2 μm, preferably 0.5–1 μm. The pore depth of the porous wax layer is equal to the thickness of the porous wax layer, allowing the etchant to contact the glass substrate through the pore structure, thereby improving the etching effect.
[0030] In one embodiment of this disclosure, the etchant is an inorganic acid solution, including a hydrofluoric acid solution, wherein the hydrofluoric acid content in the hydrofluoric acid solution is 4-12% by weight, preferably 8-12% by weight; optionally, the inorganic acid solution further includes hydrochloric acid and / or nitric acid; the etching temperature is 15-30°C, preferably 20-25°C, and the etching time is 10-30 min, preferably 15-20 min. In the above embodiments, the etchant can be a hydrofluoric acid solution, a mixture of hydrofluoric acid and hydrochloric acid, or a mixture of hydrofluoric acid and nitric acid.
[0031] In one embodiment of this disclosure, the method further includes: forming a colloidal protective layer on the main surface of the glass substrate away from the porous wax layer before etching, and removing the colloidal protective layer after etching to form a structure in which micropores are distributed on the same side of the main surface of the glass substrate; the colloidal protective layer can be a material that is not reacted or dissolved by the etchant, preferably, the colloidal protective layer comprises a resin, the resin being selected from one or more of epoxy resin, silicone resin, polyester resin, and polyamide resin. In a preferred embodiment, the thickness of the colloidal protective layer is 0.5–5 μm. In the above embodiments, by selecting a preferred colloidal protective layer, the main surface of the glass substrate away from the porous wax layer can be protected from the influence of the etchant.
[0032] In one embodiment of this disclosure, the method further includes pretreating the glass substrate before coating the paraffin dispersion. The pretreatment includes chemical cleaning and / or ultrasonic cleaning of the surface of the glass substrate. The chemical cleaning conditions may include scrubbing the glass substrate with a detergent to remove most of the grease. The detergent may be one or more of surfactants, oxidants, and alkaline chemical detergents. The ultrasonic cleaning conditions may include ultrasonic cleaning of the glass substrate with an alcohol solvent or a ketone solvent, with an ultrasonic cleaning power of 10–80 kHz and a time of 5–60 min. In a preferred embodiment, the alcohol solvent may be ethanol, and the ketone solvent may be acetone. In the above embodiments, by selecting the preferred pretreatment, impurities on the surface of the glass substrate can be removed.
[0033] In one embodiment of this disclosure, the method of coating a paraffin dispersion onto a glass substrate includes one or more of spraying, spin coating, and blade coating, with spraying being preferred. In the above-mentioned preferred coating method, the paraffin dispersion can be uniformly coated onto the glass substrate, forming a porous wax layer of suitable thickness.
[0034] In one embodiment of this disclosure, after etching is complete, the porous wax layer is removed using an organic solvent selected from one or more of ethanol, isopropanol, and acetone. In the above embodiments, by selecting a preferred organic solvent, the porous wax layer on the glass substrate can be removed. In embodiments where a colloidal protective layer is coated, the aforementioned organic solvent can also remove the colloidal protective layer. In a specific embodiment, such as... Figure 1As shown, the method for preparing antireflective and anti-reflective glass includes: S1, cleaning the surface of the glass substrate to remove impurities; S2, dispersing paraffin in an organic solvent to obtain a paraffin dispersion with a paraffin concentration of 0.01–0.03 g / mL; S3, coating the paraffin dispersion onto the main surface of the glass substrate and removing the organic solvent to obtain a porous wax layer; S4, coating the back of the glass substrate with a colloidal protective layer to protect the back of the glass substrate from the influence of the etchant; S5, etching the glass substrate covered with the porous wax layer using an etchant; and S6, removing the porous wax layer and the colloidal protective layer from the glass substrate.
[0035] The second aspect of this disclosure provides an anti-reflective and anti-reflective glass prepared by the method described in the first aspect of this disclosure, comprising a glass substrate and a plurality of micropores distributed on the surface of the glass substrate, wherein the micropores are blind pores and the average diameter of the opening of the micropores is 8 to 14 μm; wherein the micropores are blind pores, meaning that the depth of the micropores is less than the thickness of the glass substrate.
[0036] The inventors of this disclosure discovered that when multiple micropores are distributed on the surface of the antireflective and anti-reflective glass, and the average diameter of the micropore openings is in the range of 8–14 μm, Fresnel reflection caused by the abrupt change in the refractive index coefficient of the medium when light enters the glass from air can be significantly reduced, thereby reducing the reflectivity of the glass surface and increasing the transmittance. In a preferred embodiment, when the average diameter of the micropore openings is 8–10 μm, the antireflective effect of the glass can be further improved.
[0037] In one embodiment of this disclosure, the depth of the micropores is 0.2–0.5 μm, and the distance between the openings of two adjacent micropores is less than 5 μm, preferably 0.5–2 μm. All the micropores are distributed on one side of the main surface of the glass substrate, and are arranged randomly or densely on this main surface. The shape of the micropores is not particularly limited. In a preferred embodiment, the opening shape of the micropores can be circular or elliptical, and the channel shape can be semi-circular, cylindrical, or cylindrical with an arc-shaped bottom. The distance between the openings of two adjacent micropores refers to the minimum distance between the edges of two adjacent micropores; the depth of the micropore refers to the distance from the bottom of the micropore to the main surface of the glass substrate. In the above embodiment, by selecting the preferred micropore structure, the reflectivity of the glass can be further reduced and the transmittance increased.
[0038] In one embodiment of this disclosure, the micropores are formed by etching at least a portion of the surface of the glass substrate. That is, the antireflective and anti-reflective glass is made of the same material as the glass substrate, thus exhibiting good integrity.
[0039] This disclosure provides an antireflective and anti-reflective glass and its preparation method. The method involves coating a glass substrate with a paraffin dispersion at a concentration of 0.01–0.03 g / mL, removing the solvent from the paraffin dispersion, thus forming a porous wax layer with a suitable pore structure on the glass substrate surface. Then, wet etching is used to selectively etch the glass substrate, resulting in an antireflective and anti-reflective glass with multiple micropores distributed on its surface. The average diameter of the openings of these micropores is in the range of 8–14 μm, resulting in a reduced reflectivity and increased transmittance in the prepared antireflective and anti-reflective glass. The method disclosed herein is simple to operate, easy to implement, and low in cost.
[0040] The present disclosure will be further illustrated by the following examples, but the present disclosure is not limited thereto.
[0041] In the following examples and comparative examples, the main component of the detergent is a surfactant, and the paraffin is purchased from Sanjin Shop Company, product number 56 semi-crystal, with a melting point of 56°C, and mainly contains hydrocarbons with 18 to 30 carbon atoms.
[0042] Unless otherwise specified, all other raw materials used are commercially purchased products.
[0043] The average diameter, depth, and spacing of the micropore openings were measured using a scanning electron microscope, model TESCAN MIRA3 GM.
[0044] The thickness of the porous wax layer was measured using a scanning electron microscope, model TESCAN MIRA3GM.
[0045] Example 1
[0046] (1) Use detergent (mainly surfactant) to scrub the surface of the glass substrate to remove most of the grease and other impurities; use ethanol, acetone, isopropanol and ethanol in sequence to ultrasonically clean the glass substrate. The ultrasonic cleaning power is 45KHz and the time is 20min to remove the residual impurities. After cleaning, blow the glass substrate dry for later use.
[0047] (2) Paraffin is dispersed in ethanol and heated to 70°C to obtain a paraffin dispersion. The paraffin dispersion is sprayed onto the main surface of a glass substrate and dried at 20°C to allow the solvent to evaporate, resulting in a glass substrate with a porous wax layer on the surface. The paraffin concentration in the paraffin dispersion is 0.02 g / mL, and the thickness of the porous wax layer is 1 μm.
[0048] (3) A layer of resin is brushed onto the back of a glass substrate with a porous wax layer on its surface. After drying, a colloidal protective layer is formed. The glass substrate with the colloidal protective layer is immersed in a hydrofluoric acid solution (the hydrofluoric acid content in the hydrofluoric acid solution is 8% by weight). The hydrofluoric acid contacts the glass substrate through the pores of the porous wax layer and etches the corresponding area. After etching, the porous wax layer and the colloidal protective layer are washed away with ethanol to obtain antireflective and anti-reflective glass 1. Multiple micropores are distributed on its surface. The micropores are blind pores with an average opening diameter of 10 μm and a pore depth of 0.2 to 0.5 μm. The opening distance between two adjacent micropores is 0.5 to 2 μm.
[0049] Example 2
[0050] Similar to Example 1, except that the paraffin concentration in the paraffin dispersion is 0.015 g / mL, resulting in antireflective and anti-reflective glass 2 with multiple micropores distributed on its surface. The micropores are blind pores with an average opening diameter of 12 μm, a pore depth of 0.2–0.5 μm, and a spacing of 1–4 μm between the openings of two adjacent micropores.
[0051] Example 3
[0052] Same as Example 1, except that the paraffin concentration in the paraffin dispersion is 0.03 g / mL, resulting in antireflective and anti-reflective glass 3 with multiple micropores distributed on its surface. The micropores are blind pores with an average opening diameter of 8 μm, a pore depth of 0.2 to 0.5 μm, and a spacing of 0.5 to 3 μm between the openings of two adjacent micropores.
[0053] Comparative Example 1
[0054] Similar to Example 1, except that: paraffin was dispersed in ethanol, and the paraffin concentration in the paraffin dispersion was 0.1 g / mL, resulting in control glass 1. Due to the excessively high paraffin concentration, the paraffin failed to form a porous film on the glass surface, so the hydrofluoric acid etching solution could not penetrate into the glass surface, and the glass surface could not be etched.
[0055] Comparative Example 2
[0056] Similar to Example 1, except that paraffin was dispersed in ethanol and the paraffin concentration in the paraffin dispersion was 0.001 g / mL to obtain control glass 2. Due to the low paraffin concentration, most of the glass surface was exposed. After etching with hydrofluoric acid, the surface was severely etched, resulting in a frosted surface, increased diffuse reflection, and reduced light transmittance of the glass.
[0057] Test case
[0058] The transmittance and reflectance of the glasses obtained in the examples and comparative examples were tested using a Shimadzu UV-3600 ultraviolet-visible spectrophotometer. The test results are shown in Tables 1 and 2.
[0059] Table 1
[0060]
[0061]
[0062] Table 2
[0063]
[0064] The data above shows that Examples 1-3, using the method of this disclosure, yielded antireflective and anti-reflective glass with higher transmittance and lower reflectance; Comparative Examples 1-2, not using the method of this disclosure, yielded glass with lower transmittance and higher reflectance. Therefore, the method provided in Examples 1-3 of this disclosure is superior to that in Comparative Examples 1-2.
[0065] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.
[0066] It should also be noted that the specific technical features described in the above embodiments can be combined in any suitable manner, provided that there is no contradiction.
[0067] To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.
[0068] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.
Claims
1. A method for preparing antireflective and anti-reflective glass, characterized in that, The method includes: Paraffin wax is dispersed in an organic solvent to obtain a paraffin wax dispersion. The paraffin wax dispersion is coated on the main surface of a glass substrate, and then the organic solvent is removed to obtain a glass substrate with a porous wax layer on the surface. The paraffin wax concentration in the paraffin wax dispersion is 0.02~0.03 g / mL, and the thickness of the porous wax layer is 0.5~2 μm. The glass substrate with a porous wax layer on its surface is etched using an etchant, and the porous wax layer is removed after etching is completed; The method further includes: forming a colloidal protective layer on the main surface of the glass substrate away from the porous wax layer before etching, and removing the colloidal protective layer after etching is completed; The antireflective and anti-reflective glass includes a glass substrate and a plurality of micropores distributed on the surface of the glass substrate, wherein the average diameter of the opening of the micropores is 8~10μm.
2. The method according to claim 1, characterized in that, The paraffin wax has a melting point of 50~70℃ and contains hydrocarbons with 18~30 carbon atoms; The organic solvent includes polar solvents and / or non-polar solvents. The polar solvent is selected from one or more of alcohols with 1 to 4 carbon atoms, ethers with 2 to 4 carbon atoms, and ketones with 2 to 4 carbon atoms. The non-polar solvent is selected from one or more of gasoline, carbon disulfide, xylene, benzene, chloroform, carbon tetrachloride, and naphtha.
3. The method according to claim 2, characterized in that, The polar solvent is one or more of ethanol, isopropanol, and acetone.
4. The method according to claim 2, characterized in that, The paraffin is dispersed in a polar organic solvent and heated to 50-75°C to obtain the paraffin dispersion.
5. The method according to claim 1, characterized in that, The etching agent is an inorganic acid solution, which includes a hydrofluoric acid solution, wherein the hydrofluoric acid content in the hydrofluoric acid solution is 4-12% by weight. The etching temperature is 15~30℃ and the etching time is 10~30min.
6. The method according to claim 5, characterized in that, The inorganic acid solution also includes hydrochloric acid and / or nitric acid.
7. The method according to claim 1, characterized in that, The method further includes pretreating the glass substrate before coating it with the paraffin dispersion, the pretreatment including chemical cleaning and / or ultrasonic cleaning of the surface of the glass substrate.
8. The method according to claim 1, characterized in that, The coating method includes one or more of spraying, spin coating and blade coating.
9. The method according to claim 1, characterized in that, After the etching is completed, the porous wax layer is removed using an organic solvent, which is selected from one or more of ethanol, isopropanol and acetone.
10. The method according to claim 1, characterized in that, The micropores are blind pores.
11. The method according to claim 1, characterized in that, The micropores have a depth of 0.2~0.5μm, and the opening distance between two adjacent micropores is less than 5μm; all the micropores are distributed on one side of the main surface of the glass substrate.
12. The method according to claim 1, characterized in that, The micropores are formed by etching at least a portion of the surface of the glass substrate.