Preparation process of high-refraction glass beads

Abstract

The invention discloses a preparation process of high-refraction glass beads, and relates to the technical field of glass. When the high-refraction glass beads are prepared, firstly, silicon dioxide sol and titanium dioxide sol are prepared; secondly, respectively modifying silicon dioxide sol, titanium dioxide sol, nano aluminum sol and nano zirconium dioxide sol by using mercaptopropyltrimethoxysilane to obtain modified silicon dioxide sol, modified titanium dioxide sol, modified nano aluminum sol and modified nano zirconium dioxide sol; mixing the modified titanium dioxide sol and the modified zirconium dioxide sol to obtain composite sol A, and mixing the modified silicon dioxide sol and the modified nano aluminum sol to obtain composite sol B; and finally, sequentially modifying the glass beads by using the composite sol A and the composite sol B through a dip-coating method, and carrying out heat treatment to obtain the high-refraction glass beads. The high-refractive-index glass beads prepared by the method have good wear resistance and high refractive index.

Description

Technical Field

[0001] The invention relates to the technical field of glass, in particular to a preparation process of high-refractive glass microbeads. Background Art

[0002] High-refractive glass beads can be made by applying a layer of high-refractive index transparent coating on the surface of ordinary glass beads through special technology. This coating gives the beads a higher refractive index, enabling them to show better refraction and reflection effects under light exposure without relying on special materials such as lead glass, titanate glass or lanthanide glass; the refractive index of high-refractive glass beads is usually much higher than that of ordinary glass beads, and this feature makes them have a wide range of application value in many fields.

[0003] In application scenarios, high-refractive glass microspheres are widely used to enhance the visual effects of products due to their unique optical properties. For example, in the coating and ink industry, they can significantly improve the gloss and hiding power of the coating, making the coating surface brighter and fuller; in the field of plastics and rubber products, the addition of high-refractive glass microspheres can improve the transparency and texture of the product, making its appearance more beautiful; in the field of optics, they are used to manufacture optical components such as reflectors and lenses, as well as for the encapsulation of LED light sources to improve luminous efficiency and light uniformity;

[0004] However, traditional glass microspheres have limitations in some aspects, such as insufficient wear resistance and limited refractive index, which restrict their performance in high-end applications. Therefore, in order to overcome these shortcomings, researchers have developed high-wear-resistant and high-refractive-index glass microspheres. This new type of microsphere not only inherits the advantages of traditional glass microspheres, but also achieves significant improvements in wear resistance and refractive index, meeting the market demand for high-quality optical materials and promoting scientific and technological progress in multiple industries such as optics, coatings, and plastics. Summary of the invention

[0005] The purpose of the present invention is to provide a preparation process of high-refractive glass microspheres to solve the problems existing in the prior art.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0007] A method for preparing high-refractive glass microspheres comprises the following preparation steps:

[0008] (1) TEOS and anhydrous ethanol were mixed at a volume ratio of 1:25 for 30 min to obtain a silicon solution, 30 wt% ammonia water and anhydrous ethanol were mixed at a volume ratio of 1:10, stirred at room temperature for 30 min, heated to 50° C., and the silicon solution was added dropwise at a rate of 1 mL / min. After the addition was completed, the mixture was stirred under a sealed condition for 1 h. After the stirring was completed, a silica sol was obtained; anhydrous ethanol was used to adjust the solid content of the silica sol to 2%-3%, acetic acid was used to adjust the pH to 3-4, and 0.2-0.3 times the mass of the silica sol was added with mercaptopropyltrimethoxysilane, and the mixture was stirred at room temperature for 30 min to obtain a modified silica sol;

[0009] (2) Tetrabutyl titanate, anhydrous ethanol and pure water were mixed, the pH was adjusted to 2-3 with 36wt% hydrochloric acid solution, and aged at room temperature for 20 days to obtain a titanium dioxide sol; the solid content of the titanium dioxide sol was adjusted to 2%-3% with anhydrous ethanol, the pH was adjusted to 3-4 with acetic acid, 0.2-0.3 times the mass of the titanium dioxide sol was added with mercaptopropyltrimethoxysilane, and stirred at room temperature for 30 minutes to obtain a modified titanium dioxide sol;

[0010] (3) mixing nano aluminum sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3-4 with acetic acid, adding 0.2-0.3 times the mass of nano aluminum sol mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes to obtain modified nano aluminum sol; mixing nano zirconium dioxide sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3-4 with acetic acid, adding 0.2-0.3 times the mass of nano aluminum sol mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes to obtain nano zirconium dioxide sol;

[0011] (4) Mixing modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide, and stirring at room temperature for 30 min to obtain composite sol A; mixing modified nano-aluminum sol, anhydrous ethanol, modified silicon dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide, and stirring at room temperature for 30 min to obtain composite sol B;

[0012] (5) The glass microbeads are immersed in acetone and ultrasonically treated for 10-20 min, and then immersed in anhydrous ethanol and ultrasonically treated for 10-20 min, washed with pure water for 3-4 times, dried at 50-60°C for 2-3 h, cooled to room temperature, impregnated with composite sol A to form a coating, heat treated at 100-110°C for 1-2 h, and cooled to room temperature; impregnated with composite sol B to form a coating, heat treated at 100-110°C for 1-2 h, and obtained high-refractive glass microbeads.

[0013] As an optimization, the volume ratio of 30 wt % ammonia water to tetraethyl orthosilicate in step (1) is 1:1.

[0014] As an optimization, the volume ratio of tetrabutyl titanate, anhydrous ethanol and pure water in step (2) is 2:1:25.

[0015] As an optimization, the parameters of the nano zirconium dioxide sol in step (3) are: particle size 20-30 nm, solid content 30%, pH 4-6.

[0016] As an optimization, the parameters of the nano aluminum sol in step (3) are: particle size 10-20 nm, solid content 20%, pH 3-5.

[0017] As an optimization, the mass ratio of the modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide in step (4) is 1:10:10:0.02:1.

[0018] As an optimization, the mass ratio of the modified nano-aluminum sol, anhydrous ethanol, modified silica sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide in step (4) is 1:10:10:0.02:1.

[0019] As an optimization, the model of the glass microbeads in step (5) is HL20.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] The invention prepares high-refractive glass microbeads by first preparing silica sol and titania sol; secondly, using mercaptopropyltrimethoxysilane to modify silica sol, titania sol, nano aluminum sol and nano zirconium dioxide sol respectively to obtain modified silica sol, modified titania sol, modified nano aluminum sol and modified nano zirconium dioxide sol; mixing the modified titania sol and modified zirconium dioxide sol to obtain composite sol A; and mixing the modified silica sol and modified nano aluminum sol to obtain composite sol B; finally, using the composite sol A and the composite sol B in sequence to modify glass microbeads by an immersion and pulling method, and obtaining high-refractive glass microbeads after heat treatment.

[0022] Firstly, a large-particle silica sol is prepared by adjusting the ratio of ammonia water, ethyl orthosilicate and anhydrous ethanol; a large-particle anatase titanium dioxide sol is prepared by adjusting the ratio of tetrabutyl titanate, anhydrous ethanol, hydrochloric acid and pure water and then aging, and the anatase titanium dioxide sol has a high refractive index; secondly, mercaptopropyl trimethoxysilane is used to modify the silica sol, titanium dioxide sol, nano aluminum sol and nano zirconium dioxide sol respectively, and the surface of the sol is provided with mercapto groups through the modification of mercaptopropyl trimethoxysilane. The modified titanium dioxide sol and the modified zirconium dioxide sol are mixed to obtain composite sol A. The zirconium dioxide and titanium dioxide in the composite sol A are both substances with high refractive index, which can improve the refractive index of glass microspheres. The modified silicon dioxide sol and the modified nano-aluminum sol are mixed to obtain composite sol B. The two sols in the composite sol are polymerized by generating disulfide bonds under the action of tetrabutylammonium iodide-hydrogen peroxide oxidation system, and the two sol particles are tightly combined together to finally generate particle composite particles. The introduction of sulfur element can also improve the refractive index of the material.

[0023] Finally, composite sol A and composite sol B are used in sequence to modify glass microbeads by the immersion pulling method to obtain high-refractive glass microbeads. The addition of zirconium dioxide and titanium dioxide sols contained in composite sol A helps to improve the refractive index and hardness of the material, and a functional layer will be modified on the glass surface. Composite sol B contains silicon dioxide and nano-aluminum components. Nano-aluminum sol has good adhesion and film-forming properties, and has strong adhesion when dried and cured, which can improve the friction and scratch resistance of the film surface, and a wear-resistant layer will be modified on the glass surface. High-refractive glass microbeads are obtained by heat treatment. The disulfide bond, as a reversible bond, breaks during high-temperature treatment and recovers at room temperature. When the glass microbeads are heat-treated, the broken disulfide bonds in composite sol A and the broken disulfide bonds in composite sol B will be cross-linked, so that the functional layer and the wear-resistant layer are cross-linked through disulfide bonds to form a denser network, thereby enhancing wear resistance and mechanical properties. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] The parameters of the nano zirconium dioxide sol used in the following examples and comparative examples are: particle size 20-30nm, solid content 30%, pH 4-6; the parameters of the nano aluminum sol used are: particle size 10-20nm, solid content 20%, pH 3-5; the model of the glass microbeads used is HL20.

[0026] Embodiment 1:

[0027] A method for preparing high-refractive glass microspheres, the method comprising the following steps:

[0028] (1) Weigh 30 wt% ammonia water and tetraethyl orthosilicate in a volume ratio of 1:1, mix tetraethyl orthosilicate and anhydrous ethanol in a volume ratio of 1:25 for 30 minutes to obtain a silicon solution, mix 30 wt% ammonia water and anhydrous ethanol in a volume ratio of 1:10, stir at room temperature for 30 minutes, heat to 50° C., add the silicon solution dropwise at a rate of 1 mL / min, stir under sealed conditions for 1 hour after the addition is completed, and obtain a silica sol after the stirring is completed; adjust the solid content of the silica sol to 2% with anhydrous ethanol, adjust the pH to 4 with acetic acid, add 0.2 times the mass of the silica sol of mercaptopropyltrimethoxysilane, and stir at room temperature for 30 minutes to obtain a modified silica sol;

[0029] (2) Weigh tetrabutyl titanate, anhydrous ethanol, and pure water in a volume ratio of 2:1:25, mix well, use 36wt% hydrochloric acid solution to adjust the pH to 3, and age at room temperature for 20 days to obtain a titanium dioxide sol; use anhydrous ethanol to adjust the solid content of the titanium dioxide sol to 2%, use acetic acid to adjust the pH to 4, add 0.2 times the mass of the titanium dioxide sol mercaptopropyltrimethoxysilane, and stir at room temperature for 30 minutes to obtain a modified titanium dioxide sol;

[0030] (3) mixing nano aluminum sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 4 with acetic acid, adding 0.3 times the mass of nano aluminum sol of mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes, and obtaining modified nano aluminum sol; mixing nano zirconium dioxide sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 4 with acetic acid, adding 0.2 times the mass of nano aluminum sol of mercaptopropyl trimethoxysilane, and stirring at room temperature for 30 minutes to obtain nano zirconium dioxide sol;

[0031] (4) Modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide were mixed in a mass ratio of 1:10:10:0.02:1, and stirred at room temperature for 30 min to obtain composite sol A; modified nano-aluminum sol, anhydrous ethanol, modified silica sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide were mixed in a mass ratio of 1:10:10:0.02:1, and stirred at room temperature for 30 min to obtain composite sol B;

[0032] (5) The glass microbeads were immersed in acetone and ultrasonically treated for 20 min, and then immersed in anhydrous ethanol and ultrasonically treated for 20 min, washed with pure water for 4 times, dried at 60°C for 3 h, cooled to room temperature, impregnated with composite sol A to form a coating, heat treated at 110°C for 2 h, and cooled to room temperature; the coating was impregnated with composite sol B to form a coating, and heat treated at 110°C for 2 h to obtain high-refractive glass microbeads.

[0033] Embodiment 2:

[0034] A method for preparing high-refractive glass microspheres, the method comprising the following steps:

[0035] (1) Weigh 30 wt% ammonia water and tetraethyl orthosilicate in a volume ratio of 1:1, mix tetraethyl orthosilicate and anhydrous ethanol in a volume ratio of 1:25 for 30 minutes to obtain a silicon solution, mix 30 wt% ammonia water and anhydrous ethanol in a volume ratio of 1:10, stir at room temperature for 30 minutes, heat to 50° C., add the silicon solution dropwise at a rate of 1 mL / min, stir under sealed conditions for 1 hour after the addition is completed, and obtain a silica sol after the stirring is completed; adjust the solid content of the silica sol to 2.5% with anhydrous ethanol, adjust the pH to 3.5 with acetic acid, add 0.25 times the mass of the silica sol of mercaptopropyltrimethoxysilane, and stir at room temperature for 30 minutes to obtain a modified silica sol;

[0036] (2) Weigh tetrabutyl titanate, anhydrous ethanol, and pure water in a volume ratio of 2:1:25, mix well, use 36wt% hydrochloric acid solution to adjust the pH to 2.5, and age at room temperature for 20 days to obtain a titanium dioxide sol; use anhydrous ethanol to adjust the solid content of the titanium dioxide sol to 2.5%, use acetic acid to adjust the pH to 3.5, add 0.25 times the mass of the titanium dioxide sol of mercaptopropyltrimethoxysilane, and stir at room temperature for 30 minutes to obtain a modified titanium dioxide sol;

[0037] (3) mixing nano aluminum sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3.5 with acetic acid, adding 0.25 times the mass of nano aluminum sol mercaptopropyl trimethoxy silane, stirring at room temperature for 30 minutes to obtain modified nano aluminum sol; mixing nano zirconium dioxide sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3.5 with acetic acid, adding 0.25 times the mass of nano aluminum sol mercaptopropyl trimethoxy silane, stirring at room temperature for 30 minutes to obtain nano zirconium dioxide sol;

[0038] (4) Modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide were mixed in a mass ratio of 1:10:10:0.02:1, and stirred at room temperature for 30 min to obtain composite sol A; modified nano-aluminum sol, anhydrous ethanol, modified silica sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide were mixed in a mass ratio of 1:10:10:0.02:1, and stirred at room temperature for 30 min to obtain composite sol B;

[0039] (5) The glass microbeads were immersed in acetone and ultrasonically treated for 15 min, then immersed in anhydrous ethanol and ultrasonically treated for 15 min, washed with pure water three times, dried at 55°C for 2.5 h, cooled to room temperature, impregnated with composite sol A to form a coating, heat treated at 105°C for 1.5 h, and cooled to room temperature; the coating was impregnated with composite sol B to form a coating, heat treated at 105°C for 1.5 h, and then cooled to room temperature. High-refractive glass microbeads were obtained.

[0040] Embodiment 3:

[0041] A method for preparing high-refractive glass microspheres, the method comprising the following steps:

[0042] (1) Weigh 30 wt% ammonia water and tetraethyl orthosilicate in a volume ratio of 1:1, mix tetraethyl orthosilicate and anhydrous ethanol in a volume ratio of 1:25 for 30 minutes to obtain a silicon solution, mix 30 wt% ammonia water and anhydrous ethanol in a volume ratio of 1:10, stir at room temperature for 30 minutes, heat to 50°C, add the silicon solution dropwise at a rate of 1 mL / min, stir under sealed conditions for 1 hour after the addition is completed, and obtain a silica sol after the stirring is completed; adjust the solid content of the silica sol to 3% with anhydrous ethanol, adjust the pH to 3 with acetic acid, add 0.3 times the mass of the silica sol of mercaptopropyltrimethoxysilane, and stir at room temperature for 30 minutes to obtain a modified silica sol;

[0043] (2) Weigh tetrabutyl titanate, anhydrous ethanol, and pure water in a volume ratio of 2:1:25, mix well, use 36wt% hydrochloric acid solution to adjust the pH to 3, and age at room temperature for 20 days to obtain a titanium dioxide sol; use anhydrous ethanol to adjust the solid content of the titanium dioxide sol to 3%, use acetic acid to adjust the pH to 3, add 0.3 times the mass of the titanium dioxide sol mercaptopropyltrimethoxysilane, and stir at room temperature for 30 minutes to obtain a modified titanium dioxide sol;

[0044] (3) mixing nano aluminum sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3 with acetic acid, adding 0.3 times the mass of nano aluminum sol mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes to obtain modified nano aluminum sol; mixing nano zirconium dioxide sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3 with acetic acid, adding 0.3 times the mass of nano aluminum sol mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes to obtain nano zirconium dioxide sol;

[0045] (4) Modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide were mixed in a mass ratio of 1:10:10:0.02:1, and stirred at room temperature for 30 min to obtain composite sol A; modified nano-aluminum sol, anhydrous ethanol, modified silica sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide were mixed in a mass ratio of 1:10:10:0.02:1, and stirred at room temperature for 30 min to obtain composite sol B;

[0046] (5) The glass microbeads were immersed in acetone for 10 min and then immersed in anhydrous ethanol for 10 min. The glass microbeads were washed with pure water for 3 times, dried at 50 °C for 2 h, cooled to room temperature, impregnated with composite sol A to form a coating, and heat treated at 100 °C for 1 h. The coating was cooled to room temperature. The composite sol B was used to impregnate and pull the coating, and heat treated at 100 °C for 1 h to obtain high-refractive glass microbeads.

[0047] Comparative Example 1:

[0048] The preparation method of high-refractive glass beads in Comparative Example 1 is different from that in Example 2 in that step (5) is modified as follows: immersing the glass beads in acetone for ultrasonic treatment for 15 minutes, then immersing them in anhydrous ethanol for ultrasonic treatment for 15 minutes, washing them with pure water three times, drying them at 55°C for 2.5 hours, cooling them to room temperature, impregnating and pulling the coating film with composite sol B, and heat treating them at 105°C for 1.5 hours to obtain high-refractive glass beads.

[0049] Comparative Example 2:

[0050] The preparation method of high-refractive glass beads in Comparative Example 2 is different from that in Example 2 in that step (5) is modified as follows: immersing the glass beads in acetone for ultrasonic treatment for 15 minutes, then immersing them in anhydrous ethanol for ultrasonic treatment for 15 minutes, washing them with pure water three times, drying them at 55°C for 2.5 hours, cooling them to room temperature, impregnating and pulling the coating film with composite sol A, and heat treating them at 105°C for 1.5 hours to obtain high-refractive glass beads.

[0051] Comparative Example 3:

[0052] The preparation method of the high-refractive glass microbeads in Comparative Example 3 differs from that in Example 2 in that step (4) is modified as follows: zirconium dioxide sol, anhydrous ethanol, and titanium dioxide sol are mixed in a mass ratio of 1:10:10, and stirred at room temperature for 30 minutes to obtain composite sol A; nano-aluminum sol, anhydrous ethanol, and silicon dioxide sol are mixed in a mass ratio of 1:10:10, and stirred at room temperature for 30 minutes to obtain composite sol B.

[0053] Test Example 1:

[0054] Test method:

[0055] Wear resistance test: The wear resistance of the protective layer was tested using an abrasion tester, and the rotation speed of the abrasion tester stage was set to 100 r / min. The high refractive glass microspheres prepared in the examples and comparative examples were subjected to wear tests until the protective layer was worn and the base glass microspheres were exposed, and the time taken for this process was recorded. The results are shown in Table 1.

[0056] Refractive index test: The refractive index was measured by oil immersion method. The results are shown in Table 1.

[0057] Table 1

[0058] Duration (h) Refractive Index Example 1 824 1.91 Example 2 825 1.92 Example 3 825 1.92 Comparative Example 1 482 1.71 Comparative Example 2 531 1.89 Comparative Example 3 757 1.87

[0059] From the comparison of the experimental data of Examples 1 to 3 and Comparative Examples 1 to 3 in Table 1, it can be found that the high-refractive glass microspheres prepared in the present invention have good wear resistance and a relatively high refractive index.

[0060] By comparison, the wear resistance of Examples 1 to 3 is better than that of Comparative Examples 1 to 3, indicating that the composite sol B contains silicon dioxide and nano-aluminum components, and the nano-aluminum sol has good adhesion and film-forming properties, and has strong adhesion when dried and solidified, which can improve the friction and scratch resistance of the film surface, and will modify a wear-resistant layer on the glass surface, and then obtain high-refractive glass beads through heat treatment. The disulfide bond, as a reversible bond, breaks during high-temperature treatment and recovers at room temperature. When the glass beads are heat-treated, the broken disulfide bonds in the composite sol A and the broken disulfide bonds in the composite sol B will be cross-linked, so that the functional layer and the wear-resistant layer are cross-linked through disulfide bonds to form a denser network, thereby enhancing the wear resistance and mechanical properties.

[0061] By comparison, the refractive index of Examples 1 to 3 is better than that of Comparative Examples 1 to 3, indicating that firstly, by adjusting the ratio of ammonia water, ethyl orthosilicate, and anhydrous ethanol, a large-particle silica sol is prepared; by adjusting the ratio of tetrabutyl titanate, anhydrous ethanol, hydrochloric acid, and pure water, and then by aging, a large-particle anatase titanium dioxide sol is prepared, and the anatase titanium dioxide sol has a higher refractive index; secondly, mercaptopropyl trimethoxysilane is used to modify the silica sol, titanium dioxide sol, nano aluminum sol, and nano zirconium dioxide sol, respectively. , the surface of the sol is modified with mercaptopropyltrimethoxysilane so that the surface of the sol is provided with mercapto groups, and the modified titanium dioxide sol and the modified zirconium dioxide sol are mixed to obtain a composite sol A. The zirconium dioxide and titanium dioxide in the composite sol A are both substances with high refractive index, which can increase the refractive index of the glass microbeads; the modified silica sol and the modified nano-aluminum sol are mixed to obtain a composite sol B; the two sols in the composite sol are polymerized by generating disulfide bonds under the action of a tetrabutylammonium iodide-hydrogen peroxide oxidation system, and the introduction of sulfur element can also increase the refractive index of the material.

[0062] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and scope of the equivalent elements of the claims be included in the invention. Any marking in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for preparing high-refractive glass microspheres, characterized in that: The method comprises the following preparation steps: (1) TEOS and anhydrous ethanol were mixed at a volume ratio of 1:25 for 30 min to obtain a silicon solution, 30 wt% ammonia water and anhydrous ethanol were mixed at a volume ratio of 1:10, stirred at room temperature for 30 min, heated to 50° C., and the silicon solution was added dropwise at a rate of 1 mL / min. After the addition was completed, the mixture was stirred under a sealed condition for 1 h. After the stirring was completed, a silica sol was obtained; anhydrous ethanol was used to adjust the solid content of the silica sol to 2%-3%, acetic acid was used to adjust the pH to 3-4, and 0.2-0.3 times the mass of the silica sol was added with mercaptopropyltrimethoxysilane, and the mixture was stirred at room temperature for 30 min to obtain a modified silica sol; (2) Tetrabutyl titanate, anhydrous ethanol and pure water were mixed, the pH was adjusted to 2-3 with 36wt% hydrochloric acid solution, and aged at room temperature for 20 days to obtain a titanium dioxide sol; the solid content of the titanium dioxide sol was adjusted to 2%-3% with anhydrous ethanol, the pH was adjusted to 3-4 with acetic acid, 0.2-0.3 times the mass of the titanium dioxide sol was added with mercaptopropyltrimethoxysilane, and stirred at room temperature for 30 minutes to obtain a modified titanium dioxide sol; (3) mixing nano aluminum sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3-4 with acetic acid, adding 0.2-0.3 times the mass of nano aluminum sol mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes to obtain modified nano aluminum sol; mixing nano zirconium dioxide sol and anhydrous ethanol in a volume ratio of 1:10, adjusting the pH to 3-4 with acetic acid, adding 0.2-0.3 times the mass of nano aluminum sol mercaptopropyl trimethoxysilane, stirring at room temperature for 30 minutes to obtain nano zirconium dioxide sol; (4) Mixing modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide, and stirring at room temperature for 30 min to obtain composite sol A; mixing modified nano-aluminum sol, anhydrous ethanol, modified silicon dioxide sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide, and stirring at room temperature for 30 min to obtain composite sol B; (5) The glass microbeads are immersed in acetone and ultrasonically treated for 10-20 min, and then immersed in anhydrous ethanol and ultrasonically treated for 10-20 min, washed with pure water for 3-4 times, dried at 50-60°C for 2-3 h, cooled to room temperature, impregnated with composite sol A to form a coating, heat treated at 100-110°C for 1-2 h, and cooled to room temperature; impregnated with composite sol B to form a coating, heat treated at 100-110°C for 1-2 h, and obtained high-refractive glass microbeads.

2. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: In step (1), the volume ratio of 30 wt% ammonia water to tetraethyl orthosilicate is 1:

1.

3. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: In step (2), the volume ratio of tetrabutyl titanate, anhydrous ethanol and pure water is 2:1:

25.

4. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: The parameters of the nano zirconium dioxide sol in step (3) are: particle size 20-30nm, solid content 30%, pH 4-6.

5. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: The parameters of the nano aluminum sol in step (3) are: particle size 10-20nm, solid content 20%, pH 3-5.

6. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: In step (4), the mass ratio of the modified zirconium dioxide sol, anhydrous ethanol, modified titanium dioxide sol, tetrabutylammonium iodide, and 30wt% hydrogen peroxide is 1:10:10:0.02:

1.

7. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: In step (4), the mass ratio of the modified nano-aluminum sol, anhydrous ethanol, modified silica sol, tetrabutylammonium iodide, and 30 wt% hydrogen peroxide is 1:10:10:0.02:

1.

8. The method for preparing high-refractive glass microspheres according to claim 1, characterized in that: The model of the glass microspheres in step (5) is HL20.