Anti-reflection coating liquid, preparation method thereof and anti-reflection coated glass

Abstract

The invention discloses an anti-reflection coating liquid, a preparation method thereof and anti-reflection coated glass, and the preparation method of the anti-reflection coating liquid comprises the following steps: adding an auxiliary agent and a solvent into silica sol, and uniformly mixing to obtain the anti-reflection coating liquid, the preparation method of the silica sol comprises the following steps: mixing and uniformly stirring water, an emulsifier and an initiator, adding styrene and a cationic monomer into the mixture, heating to 70-85 DEG C to carry out polymerization reaction, and cooling after reacting for 3-5 hours to obtain an emulsion; and adding siloxane, a silane coupling agent, a catalyst and water into the emulsion, uniformly stirring, and carrying out hydrolytic polycondensation reaction at 50-70 DEG C to obtain the silica sol. According to the preparation method of the anti-reflection coating liquid, the used raw materials, auxiliaries and solvents are low in price, and the cost of the raw materials can be reduced; the particle size distribution of the silica sol in the prepared anti-reflection coating liquid is uniform, so that the prepared anti-reflection coated glass has high light transmittance, high hardness and excellent smudginess resistance and weather resistance.

Description

Technical Field

[0001] This invention belongs to the field of coating liquid technology, specifically relating to an antireflective coating liquid, its preparation method, and an antireflective coated glass prepared from the antireflective coating liquid. Background Technology

[0002] With the world facing increasing energy shortages, research on photovoltaic (PV) modules for solar power generation has become a hot topic. Coating one or more anti-reflective films onto the cover glass surface of PV modules can reduce light reflection loss from the cell surface, increase light transmittance, and improve the cell's power generation efficiency.

[0003] Currently, the main methods for preparing antireflective coatings for photovoltaic glass include acid etching, magnetron sputtering, vapor deposition, and sol-gel methods. Compared to other methods, the sol-gel method requires simple equipment, the reaction is easy to carry out, the temperature is relatively low, and the cost is low, thus becoming the main method for preparing photovoltaic glass. The sol-gel method for preparing photovoltaic glass requires the use of antireflective coating solutions to roll-coat the glass substrate. The physicochemical properties of the antireflective coating solution directly affect the application performance of the final photovoltaic glass product. However, the preparation of the coating solution involves problems such as a large variety of expensive raw materials, complex preparation processes, and long reaction times. When applied to coated glass, it may have disadvantages such as low hardness and poor resistance to dirt.

[0004] For example, Chinese invention patent CN109665719B, entitled "A Self-Cleaning High-Reflection Coating Solution and Its Preparation Method and Self-Cleaning High-Reflection Solar Glass," discloses a method for preparing a coating solution, the steps of which include: (1) preparing a cationic polystyrene emulsion; (2) preparing a core-shell silica microsphere sol; (3) preparing a core-shell silica / titanium dioxide microsphere sol; and (4) preparing a coating solution. The antireflective glass prepared using this coating solution has good antireflection effect and a small water contact angle, but the preparation time of the core-shell silica / titanium dioxide microsphere sol is long, increasing production costs. Summary of the Invention

[0005] In view of this, in order to overcome the shortcomings of the prior art, the object of the present invention is to provide an antireflective coating liquid, a method for preparing the same, and an antireflective coated glass prepared from the antireflective coating liquid.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for preparing an antireflective coating solution, comprising the following steps: Additives and solvents are added to silica sol and mixed evenly to obtain the antireflective coating solution. The preparation method of the silica sol includes the following steps: After mixing and stirring water, emulsifier and initiator evenly, styrene and cationic monomer are added, and the temperature is raised to 70-85℃ to carry out the polymerization reaction. After reacting for 3-5 hours, the temperature is lowered to obtain the emulsion. Siloxane, silane coupling agent, catalyst, and water are added to an emulsion and stirred until homogeneous. A hydrolysis-condensation reaction is then carried out at 50-70°C to obtain the silica sol. By introducing cationic monomers into the polystyrene chain segments, the polystyrene polymer is transformed from neutral to cationic, allowing it to bind with the anionic silica sol through electrostatic attraction, resulting in good compatibility.

[0007] According to some preferred embodiments of the invention, the cationic monomer is a quaternary ammonium chloride.

[0008] According to some preferred embodiments of the present invention, the cationic monomer is one or more of methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, methacrylamidopropyltrimethylammonium chloride, acrylamidopropyltrimethylammonium chloride, and dimethyldiallylammonium chloride.

[0009] According to some preferred embodiments of the present invention, the mass ratio of water, emulsifier, initiator, styrene monomer, and cationic monomer in the emulsion is 70-90:0.1-0.25:0.1-0.25:10-30:0.1-1.0. In some embodiments of the present invention, the emulsifier is one or more selected from sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, dodecyl ammonium chloride, hexadecyltrimethylammonium bromide, and hexadecylpyridine bromide; the initiator is one or more selected from ammonium persulfate, potassium persulfate, sodium persulfate, azobisisopropylimidazoline hydrochloride, azobisisobutyramidine hydrochloride, and azodicyanovalerate.

[0010] According to some preferred embodiments of the present invention, the mass percentages of the emulsion, siloxane, silane coupling agent, catalyst, and water in the silica sol are 13-21:17-30:1-5:0.01-0.1:8-13. In some embodiments of the present invention, the siloxane is one or more selected from tetramethyl orthosilicate, tetraethyl orthosilicate, methyltrimethoxysilane, methyltriethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane, and phenyltriethoxysilane; the silane coupling agent is γ-glycidoxypropyltrimethoxysilane and / or γ-methacryloyloxypropyltrimethoxysilane; and the catalyst is hydrochloric acid or nitric acid.

[0011] According to some preferred embodiments of the present invention, the mass percentages of silica sol, additives and solvent in the antireflective coating solution are 25-35: 2-5: 60-70.

[0012] According to some preferred embodiments of the present invention, the adjuvant is propylene glycol methyl ether acetate or diethylene glycol ethyl ether.

[0013] According to some preferred embodiments of the invention, the solvent is ethanol and / or isopropanol.

[0014] The present invention also provides an antireflective coating solution, which is prepared by the antireflective coating solution preparation method described above.

[0015] Preferably, the antireflective coating solution of the present invention comprises, by weight percentage, the following components: 25%-35% silica sol, 2%-5% additives and 60%-70% solvent.

[0016] This invention further provides an anti-reflective coated glass, wherein one side of the anti-reflective coated glass has an anti-reflective coating prepared from the anti-reflective coating solution described above. The method for preparing this anti-reflective coated glass includes the following steps: After cleaning and drying the photovoltaic glass substrate, an anti-reflective coating solution is applied to the photovoltaic glass substrate using a coating process such as spraying, roller coating, dip coating, or spin coating. After the surface dries, it is cured at 150-250℃ for 5-10 minutes, and then tempered at 650-750℃ for 5-10 minutes to prepare anti-reflective glass.

[0017] Compared with the prior art, the present invention has the following beneficial effects: 1) The silica sol in the antireflective coating solution of the present invention has a uniform particle size distribution, and the antireflective coating prepared by the antireflective coating solution has a uniform pore size, which can effectively improve the hardness, dirt resistance and weather resistance of the antireflective coating. 2) The preparation method of the antireflective coating solution of the present invention can realize continuous production, simplify the process flow, and use inexpensive raw materials, additives and solvents, which can reduce raw material costs and improve the cost performance of the antireflective coating solution. 3) The anti-reflective coated glass of the present invention has high light transmittance, high hardness and excellent resistance to dirt and weathering. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] Example 1: This example provides an antireflective coating solution and its preparation method. The preparation method of the antireflective coating solution includes the following steps: Step 1: Prepare the emulsion.

[0020] Using a three-necked flask equipped with a thermometer and a stirrer, add 0.2 g of hexadecyltrimethylammonium bromide, 0.2 g of azobisisopropylimidazoline hydrochloride, and 74.6 g of pure water. Start stirring, then add 25.0 g of styrene and 0.5 g of acryloyloxyethyltrimethylammonium chloride to the three-necked flask. Stir until homogeneous and heat to 75°C to carry out the polymerization reaction. After reacting for 3 hours, cool down to 60°C to obtain a cationic polystyrene emulsion. In this example, the particle size of the cationic polystyrene emulsion is 60 nm.

[0021] Step 2: Prepare silica sol.

[0022] Add 150g tetraethyl orthosilicate, 25g γ-glycidoxypropyltrimethoxysilane and 265g isopropanol to the emulsion in step 1 and start stirring; then dissolve 0.25g nitric acid in 60g water to obtain a catalyst solution, add the catalyst solution to a three-necked flask, heat to 60℃ and keep warm for 4h to carry out hydrolysis and polycondensation reaction, then cool to room temperature, and the discharged product is silica sol.

[0023] Step 3: Prepare the antireflective coating solution.

[0024] Add 52g of propylene glycol methyl ether acetate and 1081g of isopropanol to the silica sol in step 2 above, and mix well to obtain the antireflective coating solution.

[0025] This embodiment also provides an antireflective coating solution prepared by the above preparation method.

[0026] Comparative Example 1: Comparative Example 1 provides an antireflective coating solution and its preparation method. This comparative example is basically the same as Example 1, except that 0.5g of acryloyloxyethyltrimethylammonium chloride is not added in step 1 of Comparative Example 1, that is, no cationic monomer is added. The particle size of the polystyrene emulsion prepared in step 1 of Comparative Example 1 is 100nm.

[0027] This comparative example also provides an antireflective coating solution prepared by the above preparation method.

[0028] Comparative Example 2: Comparative Example 2 provides an antireflective coating solution and its preparation method. This comparative example is basically the same as Example 1, except that the amount of styrene added in step 1 of Comparative Example 2 is larger, which is 40.0g. The remaining steps are the same as in Example 1.

[0029] In Comparative Example 2, the amount of styrene used is relatively large. During the free radical polymerization reaction in step 1, the molecular weight and particle size of the polymer macromolecules will gradually increase with the increase of the amount of styrene monomer. In this comparative example, the particle size of the cationic polystyrene emulsion obtained in step 1 is 200 nm.

[0030] Example 2: Performance evaluation of antireflective coating solution.

[0031] After cleaning and drying a photovoltaic glass substrate, the antireflective coating liquid prepared in Example 1, Comparative Example 1 and Comparative Example 2 was coated onto the photovoltaic glass substrate using a roller coating process. After the surface dried, it was cured at 200°C for 10 minutes and then tempered at 700°C for 10 minutes to prepare three different antireflective coated glasses. The following tests were performed on each antireflective coated glass, and the test results are shown in Table 1.

[0032] The antireflective glass obtained from Example 1, Comparative Example 1, and Comparative Example 2 was tested, and relevant data were obtained.

[0033] Table 1 Summary of test results for various performance characteristics of antireflective coated glass The specific methods for the above tests are as follows: 1) Transmittance: The test was conducted in the 380nm-1100nm wavelength range according to the test procedure of GB / T30984.1-2015.

[0034] 2) Hardness: The pencil hardness of antireflective coated glass shall be determined in accordance with GB / T6739-2006. A hardness greater than or equal to 3H is considered qualified.

[0035] 3) Stain resistance: A rapid test was conducted using 3M Scotch 610-1PK tape. The test method was to lay the 3M tape flat on the surface of the anti-reflective coated glass, press and smooth it with a lint-free cloth, and then tear the tape at a 90° angle. The depth of the residual mark on the surface of the film was judged as 1-5, with 1 being no mark, 2 being very slight, 3 being more obvious, 4 leaving a bright white mark, and 5 being peeling off. The higher the number, the worse the stain resistance.

[0036] As shown in Table 1, the antireflective coated glass prepared by the antireflective coating solution in Example 1 exhibits superior performance compared to the antireflective coated glasses prepared by the antireflective coating solutions in Comparative Examples 1 and 2. Specifically, the antireflective coated glass prepared by the antireflective coating solution in Comparative Example 1 has a hardness of 3H, and its resistance to dirt and weathering is reduced. This is because no cationic monomer was added in step 1 of Comparative Example 1, resulting in a common emulsion product with neutral charge. This leads to poor compatibility with silica sol, resulting in uneven silica sol particle size distribution in the coating solution and uneven pore size in the prepared antireflective coated glass, thus affecting the hardness, resistance to dirt, and weathering performance of the coating. The antireflective coated glass prepared by the antireflective coating solution in Comparative Example 2 has a hardness of 2H, and its resistance to dirt and weathering is also reduced compared to Example 1. This is because the amount of styrene monomer used in step 1 of Comparative Example 2 is relatively large, resulting in a larger particle size of the styrene polymer product. When it is compounded with silica sol to prepare the coating solution, the pores in the silica sol network are too large, which affects the hardness, dirt resistance and weather resistance of the film.

[0037] This invention provides a method for preparing an antireflective coating solution. The reaction time is short and the preparation process is simple, requiring no complex formulation and enabling continuous production. Furthermore, the reaction raw materials do not require expensive substances or excessive multifunctional additives, resulting in low cost. The antireflective coated glass prepared using this invention exhibits high light transmittance, excellent resistance to dirt and weathering, and high cost-effectiveness.

[0038] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing an antireflection coating solution, characterized in that, Includes the following steps: Additives and solvents are added to silica sol and mixed evenly to obtain the antireflective coating solution. The preparation method of the silica sol includes the following steps: After mixing and stirring water, emulsifier and initiator evenly, styrene and cationic monomer are added, and the temperature is raised to 70-85℃ to carry out the polymerization reaction. After reacting for 3-5 hours, the temperature is lowered to obtain the emulsion. The siloxane, silane coupling agent, catalyst and water are added to the emulsion and stirred evenly. The mixture is then subjected to a hydrolysis-condensation reaction at a temperature of 50-70°C to obtain the silica sol.

2. The production method according to claim 1, characterized by, The cationic monomer is a quaternary ammonium chloride.

3. The preparation method according to claim 2, characterized in that, The cationic monomer is one or more of the following: methacryloyloxyethyltrimethylammonium chloride, acryloyloxyethyltrimethylammonium chloride, methacrylamidopropyltrimethylammonium chloride, acrylamidopropyltrimethylammonium chloride, and dimethyldiallylammonium chloride.

4. The production method according to claim 1, characterized by, The mass ratio of water, emulsifier, initiator, styrene monomer, and cationic monomer in the emulsion is 70-90: 0.1-0.25：0.1-0.25：10-30：0.1-1.0。 5. The preparation method according to claim 1, characterized in that, The mass percentages of the emulsion, siloxane, silane coupling agent, catalyst, and water in the silica sol are 13-21:17-30:1-5:0.01-0.1:8-13.

6. The method of claim 1, wherein, The mass percentage of silica sol, additives and solvent in the antireflective coating solution is 25-35: 2-5: 60-70.

7. The preparation method according to claim 1, characterized in that, The auxiliary agent is propylene glycol methyl ether acetate or diethylene glycol ethyl ether.

8. The method of claim 1, wherein, The solvent is ethanol and / or isopropanol.

9. An antireflective coating solution, characterized in that, It is prepared by the preparation method described in any one of claims 1-8.

10. Antireflection-coated glass, characterized in that One side of the antireflective coated glass has an antireflective coating prepared by the antireflective coating solution of claim 9.

Images