Acid-base composite antireflection coating liquid and preparation method thereof

Abstract

The invention discloses an acid-base composite anti-reflection coating liquid and a preparation method thereof. The acid-base composite anti-reflection coating liquid comprises the following components in parts by weight: 25 parts of an acid coating liquid A and 5 parts of an alkali coating liquid B. The main molecule in the coating liquid is silicon dioxide, the acid coating liquid A constructs a chain structure with hexadecyl trimethyl ammonium bromide as a template agent, good mechanical performance and long preservation time after coating are guaranteed, and the alkali coating liquid B controls the aggregation degree of silicon dioxide nano-particles through polyvinylpyrrolidone. And by adjusting the components of the solution A and the solution B, silicon dioxide with uniform particle size and uniform distribution is synthesized, so that the silicon dioxide has better wear resistance and stability while the reflectivity is reduced. The coating film is applied to photovoltaic glass to reduce light reflection.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic glass coating solution manufacturing technology, specifically relating to an acid-base composite antireflective coating solution and its preparation method. Background Technology

[0002] Early anti-reflective glass products were mainly used in the manufacture of optical lenses for cameras and microscopes, with the primary function of reducing light reflection to achieve high transmittance. The application of this function has been extended to the development of anti-reflective film glass for solar photovoltaic modules, and this has also led to the development of anti-reflective film glass for larger areas. While reducing light reflection, glare problems are alleviated to some extent. To completely eliminate glare from glass reflections and improve the lighting environment, anti-glare glass has been developed for high-end shop windows, museum display cases, airport control towers, observation decks, and picture frames. Consequently, anti-glare glass for smartphones, television displays, industrial instruments, automotive instruments, and educational panels has also emerged.

[0003] In the early 21st century, building upon previous laboratory research conducted by various research institutions and manufacturers, researchers discovered that by using SiO2, which has a refractive index similar to glass, and combining it with functional additives, anti-reflective and anti-reflective films could be prepared on the glass surface. After adjusting the production process, a single-layer dense SiO2 anti-reflective film glass with an open-pore structure was applied to photovoltaic modules. The transmittance of uncoated photovoltaic glass in the effective solar wavelength range (380~1100nm) is generally around 90.5%, while the transmittance after coating can reach around 92%, an increase of about 2 percentage points compared to the original glass. This increased transmittance of photovoltaic glass improves the power generation efficiency of photovoltaic modules, leading to its increasingly widespread application in photovoltaic modules. Summary of the Invention

[0004] The purpose of this invention is to provide an acid-base composite antireflective coating solution and its preparation method, which solves the problem of the short shelf life of coating solutions used in photovoltaic cells at present, while improving light transmittance.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: An acid-base composite antireflective coating solution comprises, by weight, 25 parts of the above-mentioned acid-based coating solution A and 5 parts of the alkaline-based coating solution B; wherein, the acid-based coating solution A is prepared from hexadecyltrimethylammonium bromide, tetraethyl orthosilicate, anhydrous ethanol, and hydrochloric acid; and the alkaline-based coating solution B is prepared from polyvinylpyrrolidone, tetraethyl orthosilicate, anhydrous ethanol, and ammonia.

[0006] Furthermore, the preparation of acid-based coating solution A includes the following steps: 1) Weigh 9g of tetraethyl orthosilicate into a beaker for later use; 2) Weigh 80g of anhydrous ethanol into another beaker, add 1g of hydrochloric acid (0.5mol / L) and 0.05-0.15g of hexadecyltrimethylammonium bromide in sequence, and stir continuously for half an hour; 3) Place the liquid from step 2) into a 50°C water bath and heat and stir it. Slowly add the previously weighed tetraethyl orthosilicate. After the tetraethyl orthosilicate has been completely added, seal the beaker and stir in the 50°C water bath for 4 hours. Remove it and stir at room temperature for 12 hours. Let it age at room temperature for 3 days.

[0007] Furthermore, the preparation of alkaline coating solution B includes the following steps: 1) Weigh 9g of tetraethyl orthosilicate into a beaker for later use; 2) Weigh 80g of anhydrous ethanol into another beaker, add 2.7g of ammonia (AR, 28wt%) and 0.1g of polyvinylpyrrolidone in sequence, and stir continuously for half an hour; 3) Place the liquid after mixing in step 2) into a 50°C water bath and heat and stir. Slowly add the previously weighed tetraethyl orthosilicate. After the tetraethyl orthosilicate has been completely added, seal the beaker. Stir in the 50°C water bath for 2 hours, then remove and stir at room temperature for 12 hours. Let it age at room temperature for 7 days.

[0008] Furthermore, the preparation method of the acid-base composite antireflective coating solution includes the following steps: (1) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine and sonicate for 30 minutes to disperse the solute in the solution; (2) The acid coating solution A and the alkaline coating solution B, which have been ultrasonically treated, are filtered to remove impurities and large particles. (3) Take 25g of the filtered acid coating solution A into a beaker, add 25g of anhydrous ethanol, and stir for 1h; take 5g of the filtered alkaline coating solution B into another beaker, add 5g of anhydrous ethanol and 3 drops of hydrochloric acid (0.5mol / l) in sequence, and stir for 1h. (4) Slowly pour the B solution after stirring for 1 hour in step (3) into the A solution after stirring for 1 hour. Then measure the pH value of the solution and control it at 5-6. Heat and stir in a 50℃ water bath for 2 hours, then take it out and stir at room temperature for 12 hours to obtain the acid-base composite anti-reflection coating solution.

[0009] The beneficial effects of this invention are as follows: (1) The present invention uses a small amount of hexadecyltrimethylammonium bromide and polyvinylpyrrolidone as additives to prepare uniform long-chain silica particles and spherical silica particles. The antireflective coating solution composed of the two has the advantages of long shelf life and good antireflection effect.

[0010] (2) The acid antireflective coating solution A prepared by the present invention has hexadecyltrimethylammonium bromide as a template agent, which accelerates the hydrolysis of SiO2 precursor, resulting in long-chain silicon dioxide particles in the antireflective coating solution. By controlling the amount of hexadecyltrimethylammonium bromide added, the degree of hydrolysis can be controlled, and the storage time can be extended.

[0011] (3) The alkaline antireflective coating solution B prepared in this invention has polyvinylpyrrolidone as a surfactant, which controls the degree of aggregation of silica nanoparticles and thus controls the transmittance after coating. By regulating it, the transmittance can be improved.

[0012] (4) The acid-base composite antireflective coating solution prepared in this invention, the alkaline antireflective coating solution B and the acidic antireflective coating solution A, under the promotion of hexadecyltrimethylammonium bromide, the spherical particles and long chain particles are combined to prepare silica particles with uniform size and good distribution. Thus, the acid-base composite antireflective coating solution has both the long storage time and good stability of the acid method and the good antireflective effect of the alkaline method. Attached Figure Description

[0013] Figure 1 This is a TEM image of acid-chain nano-silica prepared by aging the acid-method antireflective coating solution at room temperature for 3 days in this invention.

[0014] Figure 2 This is a TEM image of alkaline spherical nano-silica prepared by aging the alkaline antireflective coating solution at room temperature for 7 days in this invention.

[0015] Figure 3 This is a TEM image of the acid-base composite nano-silica prepared in Example 1 of the present invention.

[0016] Figure 4 SEM image of the acid-base composite nano-silica prepared in Comparative Example 1.

[0017] Figure 5 This is a particle size distribution diagram of acid-based chain-like nano-silica prepared by aging the acid-based antireflective coating solution at room temperature for 3 days in this invention.

[0018] Figure 6 This is a particle size distribution diagram of alkaline spherical nano-silica prepared by aging the alkaline antireflective coating solution at room temperature for 7 days in this invention.

[0019] Figure 7 This is a particle size distribution diagram of the acid-base composite nano-silica prepared in Example 1 of the present invention.

[0020] Figure 8 The image shows the FTIR spectrum of the acid-base composite nano-silica prepared in Example 1 of this invention. Detailed Implementation

[0021] To make the content of this invention easier to understand, the technical solution of this invention will be further described below with reference to specific embodiments, but this invention is not limited thereto.

[0022] The preparation of an acid-based antireflective coating solution includes the following steps: (1) Weigh 9g of tetraethyl orthosilicate into a beaker for later use.

[0023] (2) Weigh 80g of anhydrous ethanol into another beaker, add 1g of hydrochloric acid (0.5mol / l) and about 0.1g of hexadecyltrimethylammonium bromide into the beaker in sequence; stir continuously for half an hour at a speed of 100r / min and at room temperature.

[0024] (3) Place the well-mixed liquid in a 50°C water bath and heat and stir it. Slowly add the previously weighed tetraethyl orthosilicate. After the tetraethyl orthosilicate has been completely added, seal the beaker. Stir the water bath for 4 hours at a speed of 200 r / min and a temperature of 50°C. Remove the beaker and stir it at room temperature for 12 hours. Let it age at room temperature for 3 days.

[0025] The preparation of an alkaline antireflective coating solution B includes the following steps: (1) Weigh 9g of tetraethyl orthosilicate into a beaker for later use.

[0026] (2) Weigh 80g of anhydrous ethanol into another beaker, add about 2.7g of ammonia (AR, 28wt%) and 0.1g of polyvinylpyrrolidone into the beaker, and stir continuously for half an hour at a speed of 100r / min and room temperature.

[0027] (3) Place the well-mixed liquid in a 50°C water bath for heating and stirring, and slowly add the previously weighed tetraethyl orthosilicate. After the tetraethyl orthosilicate has been completely added, seal the beaker. Stir the water bath for 2 hours at a speed of 200 r / min and a temperature of 50°C. Then take it out and stir it at room temperature for 12 hours. Let it age at room temperature for 7 days.

[0028] The preparation of an acid-base composite alkaline reflective coating solution includes the following steps: (1) Take acid antireflective coating solution A that has been aged for 3 days and alkaline antireflective coating solution B that has been aged for 7 days. Place them separately in an ultrasonic machine and sonicate for 30 minutes to disperse the solutes in the solution, making the mixed solutes easier to contact, and at the same time disperse the large particles that are excessively aggregated in solution B.

[0029] (2) The samples of A and B, which have been ultrasonically treated, were filtered to remove impurities and large particles. (3) Take 25g of the filtered solution A into a beaker, add 25g of anhydrous ethanol, and stir for 1h. Take 5g of the filtered solution B into another beaker, add 5g of anhydrous ethanol and 3 drops of hydrochloric acid (0.5mol / l) in sequence (the purpose is to acidify in advance to prevent the reaction from being too violent during neutralization and causing gelation), and stir for 1h.

[0030] (4) Slowly pour the B solution after stirring for 1 hour in step (3) into the A solution after stirring for 1 hour. Then measure the pH value of the solution and control it at 5-6. Heat and stir in a 50℃ water bath for 2 hours, then take it out and stir at room temperature for 12 hours to obtain the acid-base composite anti-reflection coating solution.

[0031] Example 1 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.1g hexadecyltrimethylammonium bromide, 1g hydrochloric acid (0.5mol / l), and aged for 3d.

[0032] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0033] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B after ultrasonic treatment to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B (enhancing agent) in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After adding the solution, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0034] Example 2 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.05g hexadecyltrimethylammonium bromide, 1g hydrochloric acid (0.5mol / l), and aged for 3d.

[0035] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0036] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0037] Example 3 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.15g hexadecyltrimethylammonium bromide, 1g hydrochloric acid (0.5mol / l), aged for 3d.

[0038] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0039] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0040] Example 4 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.1g hexadecyltrimethylammonium bromide, 1g hydrochloric acid (0.5mol / l), and aged for 1d.

[0041] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0042] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0043] Example 5 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.1g hexadecyltrimethylammonium bromide, 1g hydrochloric acid (0.5mol / l), and aged for 7d.

[0044] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0045] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0046] Comparative Example 1 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 1g hydrochloric acid (0.5mol / l), and aged for 3d.

[0047] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), and aged for 7d.

[0048] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0049] Comparative Example 2 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.1g hexadecyltrimethylammonium bromide, 1g hydrochloric acid (0.5mol / l), and aged for 3d.

[0050] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), and aged for 7d.

[0051] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0052] Comparative Example 3 (1) The raw materials used in its acid antireflective coating solution A include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 1g hydrochloric acid (0.5mol / l), and aged for 3d.

[0053] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0054] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0055] Comparative Example 4 (1) The raw materials used in its acid antireflective coating solution A include: 99g tetraethyl orthosilicate, 80g anhydrous ethanol, 0.1g sodium dodecyl sulfate, 1g hydrochloric acid (0.5mol / l), and aged for 3d.

[0056] (2) The raw materials used in its alkaline antireflective coating solution B include: 9g tetraethyl orthosilicate, 80g anhydrous ethanol, 2.7g ammonia (AR, 28wt%), 0.1g polyvinylpyrrolidone, and aged for 7d.

[0057] (3) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine for 30 minutes to disperse the solute in the solution. Filter the acid coating solution A and alkaline coating solution B that have been ultrasonically treated to remove impurities and large particles. Take 25g of the filtered acid coating solution A and place it in a beaker. Add 25g of anhydrous ethanol and stir for 1 hour to obtain solution A-1. Take 5g of the filtered alkaline coating solution B and place it in another beaker. Add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid and stir for 1 hour to obtain solution B-1 (the acid-alkali ratio is 5:1). Slowly add solution B-1 to solution A-1. After the addition is complete, add diluted hydrochloric acid again to adjust the pH value to 5-6. After mixing and stirring in a 50℃ water bath for 2 hours, the solution is removed and stirred at room temperature for 12 hours to obtain the acid-base composite antireflective coating solution.

[0058] Figure 1 This is a TEM image of acid-chain nano-silica prepared by aging the acid-method antireflective coating solution at room temperature for 3 days in this invention. For the acid-catalyzed synthesis of silica, the first step is hydrolysis. Under hydrochloric acid catalysis, positively charged H+ in the hydrochloric acid... + Attacking the -OR group increases the surface voids on the other side of the silicon nucleus and makes it electrophilic. At the same time, a large number of -OH groups are generated in the system, and the positive charge transition state becomes increasingly unstable, and its hydrolysis reaction rate slows down. The next step is the condensation process. Because the -OR group has a strong electron-donating ability, the unstable positive charge intermediate transition state during hydrolysis begins to stabilize. This indicates that the initial hydrolysis reaction rate is the fastest, and the condensation reaction rate of the initial hydrolysis product is also the fastest. This leads to the formation of an open three-dimensional network structure first, and then further reaction to form a cross-linked chain structure. As can be seen from the figure, the silica prepared by the acid method has a small particle size, and there are gaps between the particles, forming a chain-like shape. Because the porosity of the film formed after hydrolysis and condensation is low, its refractive index does not decrease much, so its anti-reflection effect is poor.

[0059] Figure 2 This is a TEM image of spherical nano-silica prepared by aging the alkaline antireflective coating solution at room temperature for 7 days in this invention. The hydrolysis reaction under ammonia catalysis is influenced by the OH groups in the ammonia solution. - The ionic radius is small, allowing direct nucleophilic attack on the silicon nucleus, making it negatively charged, weakening the Si-O bond and eventually breaking it. This step involves fewer intermediate processes, resulting in relatively fast hydrolysis. However, the -OR group can hinder the hydrolysis rate to some extent due to steric hindrance. Tetraethyl orthosilicate contains a large number of -OR groups on its silicon atoms, so the initial hydrolysis rate is slow. But once the first -OH group is replaced, subsequent OH ion attacks become more successful, and the hydrolysis rate increases progressively. During the polycondensation process, OH... -The intermediate negative charge transition state formed by the attack on silicon atoms becomes increasingly stable as the -OH group replaces the electron-donating -OCH group. This indicates that the hydrolysis reaction rate continuously accelerates, and the condensation reaction rate of the completely hydrolyzed product is also the fastest. As a result, due to the formation and nucleation of the silicon source, continuous growth occurs, eventually forming monodisperse spherical SiO2 particles. As can be seen from the figure, the silica prepared by the alkaline method has a larger particle size, and the particles easily agglomerate and aggregate together. The nanoparticles have a large number of pores, thus the antireflective coating has a relatively low refractive index.

[0060] Figure 3 The image shows a TEM image of the acid-base composite nano-silica prepared in Example 1 of this invention. As can be seen from the image, the presence of the acid-prepared silica constrains the silica particles prepared by the alkali method, resulting in uniform silica particle size and good distribution. The silica particles prepared by the acid method are too small, resulting in insufficient contrast and making them difficult to observe after composite preparation. However, the particle size and distribution show that the acid-prepared silica plays a guiding and constraining role in the growth of the alkali-prepared silica, producing silica particles with uniform size and good distribution, thereby improving wear resistance and shelf life.

[0061] Figure 4 The SEM image of the acid-base composite nano-silica prepared in Comparative Example 1 shows that, due to the absence of hexadecyltrimethylammonium bromide as a template agent and polyvinylpyrrolidone as a surfactant, the silica particles prepared are uneven in size and distribution, resulting in poor antireflection effect.

[0062] Figure 5 The image shows the particle size distribution of acid-based chain-like nano-silica prepared by aging the acid-based antireflective coating solution at room temperature for 3 days in this invention. The average particle size is 9.42 nm.

[0063] Figure 6 This is a particle size distribution diagram of spherical nano-silica prepared by aging the alkaline antireflective coating solution at room temperature for 7 days in this invention. The average particle size is 20.87 nm.

[0064] Figure 7 This is a particle size distribution diagram of the acid-base composite nano-silica prepared in Example 1 of the present invention. Its average particle size is 28.62 nm. Figure 5 , Figure 6 , Figure 7 The comparison shows that after acid-base combination, the particle size of its silica increases, but its size becomes more uniform.

[0065] Figure 8 The FTIR image of the acid-base composite nano-silica prepared in Example 1 of this invention is shown at 802.2 cm⁻¹. -1 and 1048.4cm-1 Absorption peaks exist at 878.3 cm⁻¹, corresponding to the stretching and bending vibrations of the Si-O-Si bond, respectively. -1 The absorption peak present at 3366.5 cm⁻¹ corresponds to the stretching vibration absorption peak of Si-OH caused by hydrolysis and condensation processes. -1 The relatively wide absorption band belongs to the stretching vibration of the hydroxyl group in Si-OH. Analysis of the FIIR spectrum proves that the synthesis of acid-base composite nano-silica was successful.

[0066] The coating solutions obtained in the examples and comparative examples were spin-coated onto the glass surface at a speed of 1000 r / min. After curing at room temperature, the transmittance of the coated glass was measured using a UV-Vis spectrometer. The transmittance was measured after 100 cycles of rubbing with an alcohol-soaked cotton ball on both sides of the substrate coated with the antireflective film. The solution state of each sample was determined after 3 months of storage. The particle size of the liquid was then tested. The test results are shown in Table 1.

[0067] Table 1 Sample performance test results Table 1 shows that the best results were achieved when the acid-based antireflective coating solution contained 0.1 g of hexadecyltrimethylammonium bromide and was aged for 3 days, and the alkaline-based antireflective coating solution contained 0.1 g of polyvinylpyrrolidone and was aged for 7 days, with the highest transmittance of the sample being 93.34%. Comparison of the experimental example with Comparative Examples 1, 2, and 3 shows that the addition of hexadecyltrimethylammonium bromide and polyvinylpyrrolidone increases the transmittance. Comparison of the experimental example with Comparative Example 4 shows that hexadecyltrimethylammonium bromide is more effective than sodium dodecyl sulfate.

[0068] By comparing the experimental examples with the comparative examples, it can be seen that the antireflective coating prepared by using hexadecyltrimethylammonium bromide as a template agent and polyvinylpyrrolidone as a surfactant has good wear resistance.

[0069] By observing the state of each liquid after standing for 3 months, it can be seen that the chain-like silica prepared by the acid method binds the spherical silica prepared by the alkali method, preventing it from excessively condensing. This gives the solution a longer shelf life.

[0070] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. An acid-base composite antireflective coating solution, characterized in that: The components of the acid-base composite antireflective coating solution, by weight, include: 25 parts of acid coating solution A and 5 parts of alkaline coating solution B; wherein, acid coating solution A is prepared from hexadecyltrimethylammonium bromide, tetraethyl orthosilicate, anhydrous ethanol, and hydrochloric acid; and alkaline coating solution B is prepared from polyvinylpyrrolidone, tetraethyl orthosilicate, anhydrous ethanol, and ammonia.

2. The acid-base composite antireflective coating solution according to claim 1, characterized in that, The preparation of acid-based coating solution A includes the following steps: (1) Weigh 9g of tetraethyl orthosilicate into a beaker for later use; (2) Weigh 80g of anhydrous ethanol into another beaker, add 1g of 0.5mol / L hydrochloric acid and 0.05-0.15g of cetyltrimethylammonium bromide in sequence, and stir continuously for half an hour; (3) Place the liquid after mixing in step (2) in a 50°C water bath and heat and stir it. Slowly add the previously weighed tetraethyl orthosilicate. After the tetraethyl orthosilicate has been completely added, seal the beaker. Stir in the 50°C water bath for 4 hours, then remove and stir at room temperature for 12 hours. Let it age at room temperature for 3 days.

3. The acid-base composite antireflective coating solution according to claim 1, characterized in that, The preparation of alkaline coating solution B includes the following steps: (1) Weigh 9g of tetraethyl orthosilicate into a beaker for later use; (2) Weigh 80g of anhydrous ethanol into another beaker, add 2.7g of 28wt% ammonia water and 0.1g of polyvinylpyrrolidone in sequence, and stir continuously for half an hour; (3) Place the liquid after mixing in step (2) in a 50°C water bath and heat and stir. Slowly add the previously weighed tetraethyl orthosilicate. After the tetraethyl orthosilicate is completely added, seal the beaker. Stir in the 50°C water bath for 2 hours, then take it out and stir at room temperature for 12 hours. Let it age at room temperature for 7 days.

4. The method for preparing the acid-base composite antireflective coating solution according to claim 1, characterized in that, Includes the following steps: (1) Take acid coating solution A that has been aged for 3 days and alkaline coating solution B that has been aged for 7 days, and place them separately in an ultrasonic machine and sonicate for 30 minutes to disperse the solute in the solution; (2) The acid coating solution A and the alkaline coating solution B, which have been ultrasonically treated, are filtered to remove impurities and large particles. (3) Take 25g of the filtered acid coating solution A into a beaker, add 25g of anhydrous ethanol, and stir for 1h; take 5g of the filtered alkaline coating solution B into another beaker, add 5g of anhydrous ethanol and 3 drops of 0.5mol / l hydrochloric acid in sequence, and stir for 1h. (4) Slowly pour the B solution after stirring for 1 hour in step (3) into the A solution after stirring for 1 hour. Then measure the pH value of the solution and control it at 5-6. Heat and stir in a 50℃ water bath for 2 hours, then take it out and stir at room temperature for 12 hours to obtain the acid-base composite anti-reflection coating solution.

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