Low-haze glass and method for producing and using the same

Abstract

The application relates to the field of glass products, and discloses a low-haze glass and a preparation method and application thereof. The method comprises the following steps: (1) polishing aluminum-silicon glass in the presence of a polishing solution to obtain an intermediate product I; (2) performing first etching on the intermediate product I in etching solution I to obtain an intermediate product II; the first etching conditions comprise: an etching thickness of 1-2 microns; the height difference of the surface of the intermediate product II within any 40 microns*40 microns range is not greater than 0.25 microns; and (3) performing second etching on the intermediate product II in etching solution II to obtain the low-haze glass; the second etching conditions comprise: an etching thickness of 30-80 microns. The low-haze glass prepared by the method has better optical uniformity, and the yield in the preparation of low-haze glass products from float aluminum-silicon glass is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of glass products, specifically to a low-haze glass, its preparation method, and its application. Background Technology

[0002] Anti-glare protective glass products for displays are manufactured using processes such as chemical etching and spraying. Protective glass treated with anti-glare technology not only boasts excellent anti-glare performance but also delivers clearer image quality and a sharper visual effect when used in displays. Currently, the main technical indicators for evaluating the quality of anti-glare glass are its optical performance, including gloss, haze, light transmittance, and sharpness.

[0003] Higher haze means a decrease in the gloss, transparency, and especially the image clarity of the protective glass. As high-end cars demand increasingly higher clarity in their in-vehicle displays, low-haze products are becoming more and more popular with customers.

[0004] Anti-glare protective glass for displays, in addition to optical performance, also requires high physical and chemical properties. This necessitates that the alkali metal and aluminum content in the glass composition be controlled within a certain range (alkali metal content not exceeding 7% by weight, and alumina content at least 7% by weight). In the production process of this type of glass, the float glass production process has a large capacity and low cost, giving it a clear advantage in product application competition. However, in actual production, the drawing amount of float glass is at least 10 times that of the overflow method, resulting in a large glass output. Furthermore, the viscosity of aluminosilicate glass is at least 100°C higher than that of ordinary soda-lime glass, leading to higher melting and forming viscosity. This makes the glass surface prone to microscopic inhomogeneity during the melting and forming process, resulting in poor optical uniformity in anti-glare protective glass products. This defect increases sharply as the haze decreases.

[0005] However, existing research still faces many challenges in addressing the poor optical uniformity of low-haze glass products. For example, firstly, improving the uniformity of the molten glass during molding requires addressing the issue of poor optical uniformity, which mainly depends on the molding channel and stirring device. This fixed investment is too large, increasing product manufacturing costs by more than 50% and directly impacting product competitiveness. Secondly, due to the characteristics of float glass, it is difficult to effectively improve glass molding and temperature control processes. Ultimately, only batch selection and verification of products can be performed, but the proportion of optical defects still cannot be effectively improved or guaranteed, resulting in numerous complaints and unstable supply. Summary of the Invention

[0006] The purpose of this invention is to solve the problem of poor optical uniformity in existing low-haze glass.

[0007] To achieve the above objectives, a first aspect of the present invention provides a method for preparing low-haze glass, the method comprising:

[0008] (1) Polishing aluminum-silicon glass in the presence of a polishing solution to obtain intermediate product I; the polishing conditions include: a polishing thickness of 10-20 μm; the polishing solution is selected from at least one of solution A, solution B and solution C;

[0009] (2) The intermediate product I is etched in etching solution I to obtain intermediate product II; the conditions for the first etching include: the etching thickness is 1-2 μm; the difference in the height of the unevenness within any 40 μm × 40 μm range on the surface of the intermediate product II is not greater than 0.25 μm;

[0010] (3) The intermediate product II is subjected to a second etching in etching solution II to obtain the low-haze glass; the conditions for the second etching include: an etching thickness of 30-80 μm. ；

[0011] Based on the total mass of solution A, solution A contains 2-8 wt% hydrofluoric acid, 1-7 wt% sulfuric acid, 1-5 wt% hydrochloric acid, 1-5 wt% nitric acid and 75-95 wt% water;

[0012] Based on the total mass of solution B, solution B contains 3-10 wt% ammonium bifluoride, 10-30 wt% sulfuric acid and 60-87 wt% water;

[0013] Based on the total mass of solution C, solution C contains 2-13 wt% hydrofluoric acid, 1-7 wt% sulfuric acid, 1-5 wt% hydrochloric acid, 3-8 wt% phosphoric acid and 71-93 wt% water.

[0014] Preferably, the polishing conditions further include a polishing rate of 2-4 μm / min.

[0015] Preferably, the polishing solution is a C solution.

[0016] Preferably, the thickness of the aluminosilicate glass is 0.3-1.8 mm.

[0017] More preferably, the thickness of the aluminosilicate glass is 1.0-1.5 mm.

[0018] More preferably, the thickness of the tin-impregnated layer on the tin side of the aluminosilicate glass is not higher than 15 μm.

[0019] Preferably, in step (2), based on the total mass of the etching solution I, the etching solution I contains 18-26 wt% ammonium bifluoride, 7-11 wt% citric acid, 2-5 wt% barium sulfate, 2-6 wt% bentonite, 8-15 wt% ferric chloride, 8-15 wt% potassium nitrate, 5-9 wt% potassium fluoride, 3-6 wt% hydrofluoric acid and 7-44 wt% water.

[0020] In a preferred embodiment, in step (2), the etching solution I contains 25-30 wt% ammonium bifluoride, 8-12 wt% ammonium fluoride, 5-10 wt% magnesium fluoride, 20-25 wt% oxalic acid, 2-3 wt% calcium phosphate, 4-6 wt% ammonium sulfate, 5-10 wt% sodium hexametaphosphate and 4-31 wt% water, based on the total mass of the etching solution I.

[0021] Preferably, in step (3), the etching solution II is selected from at least one of solution C and solution D; based on the total mass of solution D, solution D contains 5-20 wt% hydrofluoric acid, 2-15 wt% sulfuric acid, 5-20 wt% ammonium bifluoride, 1-5 wt% glucose and 40-87 wt% water.

[0022] Preferably, the method further includes coating the tin side of the aluminosilicate glass with a protective material before performing step (1).

[0023] More preferably, the protective material is selected from at least one of acid-resistant ink, UV-curable ink, and UV film.

[0024] More preferably, the thickness of the protective coating is 15-70 μm.

[0025] A second aspect of the present invention provides a low-haze glass prepared by the method described in the first aspect.

[0026] A third aspect of the invention provides the application of the low-haze glass described in the second aspect in a display device.

[0027] The low-haze glass prepared by the method provided in this invention has better optical uniformity, which greatly improves the yield of low-haze glass products prepared by float aluminum silicate glass. Attached Figure Description

[0028] Figure 1 The images show the grain surface of the low-haze glass prepared in Example 1 of this invention at different magnifications (gloss (G): 121, roughness (Ra): 0.035, haze (H): 3.5, maximum height (Rz): 0.325, average width (Rsm): 15, flash point value (sparkle): 0.78).

[0029] Figure 2 The images show the grain surface of the low-haze glass prepared in Example 3 of this invention at different magnifications (gloss (G): 25, roughness (Ra): 0.4, haze (H): 35, average width (Rsm): 55). Detailed Implementation

[0030] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0031] As previously described, a first aspect of the present invention provides a method for preparing low-haze glass, the method comprising:

[0032] (1) Polishing aluminum-silicon glass in the presence of a polishing solution to obtain intermediate product I; the polishing conditions include: a polishing thickness of 10-20 μm; the polishing solution is selected from at least one of solution A, solution B and solution C;

[0033] (2) The intermediate product I is etched in etching solution I to obtain intermediate product II; the conditions for the first etching include: the etching thickness is 1-2 μm; the difference in the height of the unevenness within any 40 μm × 40 μm range on the surface of the intermediate product II is not greater than 0.25 μm;

[0034] (3) The intermediate product II is subjected to a second etching in etching solution II to obtain the low-haze glass; the conditions for the second etching include: an etching thickness of 30-80 μm. ；

[0035] Based on the total mass of solution A, solution A contains 2-8 wt% hydrofluoric acid, 1-7 wt% sulfuric acid, 1-5 wt% hydrochloric acid, 1-5 wt% nitric acid and 75-95 wt% water;

[0036] Based on the total mass of solution B, solution B contains 3-10 wt% ammonium bifluoride, 10-30 wt% sulfuric acid and 60-87 wt% water;

[0037] Based on the total mass of solution C, solution C contains 2-13 wt% hydrofluoric acid, 1-7 wt% sulfuric acid, 1-5 wt% hydrochloric acid, 3-8 wt% phosphoric acid and 71-93 wt% water.

[0038] It should be noted that, in this invention, the polishing thickness refers to the thickness removed by polishing the non-tin surface of the aluminosilicate glass; the etching thickness refers to the thickness removed by etching the non-tin surface of the aluminosilicate glass.

[0039] In a preferred embodiment, the concentration of the hydrofluoric acid is 55 wt%, the concentration of the sulfuric acid is 98 wt%, the concentration of the hydrochloric acid is 36 wt%, the concentration of the nitric acid is 68 wt%, the concentration of the ammonium bifluoride is 95 wt%, and the concentration of the phosphoric acid is 85 wt%.

[0040] It should be noted that, in order to ensure the uniformity of the polishing solution, the polishing solution can be stirred and / or bubbled with compressed air before use. The inventors will not elaborate on this further, and those skilled in the art should not understand it as a limitation of the present invention.

[0041] Preferably, the polishing conditions further include a polishing rate of 2-4 μm / min.

[0042] More preferably, the polishing conditions further include a temperature of 20-35°C.

[0043] Preferably, the conditions for the first etching and the second etching processes are independent of each other, including a temperature of 20-40°C.

[0044] Preferably, the polishing solution is a C solution.

[0045] Preferably, the thickness of the aluminosilicate glass is 0.3-1.8 mm.

[0046] More preferably, the thickness of the aluminosilicate glass is 1.0-1.5 mm.

[0047] More preferably, the thickness of the tin-impregnated layer on the tin side of the aluminosilicate glass is not higher than 15 μm.

[0048] Preferably, in step (2), based on the total mass of the etching solution I, the etching solution I contains 18-26 wt% ammonium bifluoride, 7-11 wt% citric acid, 2-5 wt% barium sulfate, 2-6 wt% bentonite, 8-15 wt% ferric chloride, 8-15 wt% potassium nitrate, 5-9 wt% potassium fluoride, 3-6 wt% hydrofluoric acid and 7-44 wt% water.

[0049] In a preferred embodiment, in step (2), the etching solution I contains 25-30 wt% ammonium bifluoride, 8-12 wt% ammonium fluoride, 5-10 wt% magnesium fluoride, 20-25 wt% oxalic acid, 2-3 wt% calcium phosphate, 4-6 wt% ammonium sulfate, 5-10 wt% sodium hexametaphosphate and 4-31 wt% water, based on the total mass of the etching solution I.

[0050] It should be noted that in this invention, different formulations (types and / or ratios) of etching solution I can be selected according to different market demands. By using etching solution I provided by this invention in combination with specific polishing and etching processes, glass products with good gloss uniformity, high product yield, and haze values ​​meeting different market requirements can be obtained. Those skilled in the art can obtain the low-haze glass described in this invention using the formulations and process parameters provided by this invention. Furthermore, several exemplary examples are listed later in this invention to illustrate the preparation method of the low-haze glass of this invention. This invention will not elaborate on all formulations and process parameters, and those skilled in the art should not construe this as a limitation of the invention.

[0051] Preferably, in step (3), the etching solution II is selected from at least one of solution C and solution D; based on the total mass of solution D, solution D contains 5-20 wt% hydrofluoric acid, 2-15 wt% sulfuric acid, 5-20 wt% ammonium bifluoride, 1-5 wt% glucose and 40-87 wt% water.

[0052] Preferably, the glucose is a glucose aqueous solution with a concentration of 90-95 wt%.

[0053] It should be noted that, in order to ensure the uniformity of etching, etching solution I and etching solution II can be stirred and / or bubbled with compressed air before use. The inventors will not elaborate further here, and those skilled in the art should not understand this as a limitation of the present invention.

[0054] In order to meet product quality requirements, low-haze products need to have surface treatment on the air side and protection treatment on the tin side. Preferably, the method further includes: coating the tin side of the aluminosilicate glass with a protective material before performing step (1).

[0055] More preferably, the protective material is selected from at least one of acid-resistant ink, UV-curable ink, and UV film.

[0056] It should be noted that in this invention, the acid-resistant ink is AG glass protective ink, the UV-curing ink is UV-curing acid-resistant ink, and the UV film is a UV acid and alkali resistant protective film. This invention does not have special requirements for the above materials, as long as they can withstand 10wt% hydrofluoric acid for 15-30 minutes. Under the premise of ensuring the quality of the protective material product, the manufacturer and model do not need to be specified.

[0057] More preferably, the thickness of the protective coating is 15-70 μm.

[0058] As previously stated, the second aspect of the present invention provides a low-haze glass prepared by the method described in the first aspect.

[0059] As previously stated, the third aspect of the present invention provides the application of the low-haze glass described in the second aspect in a display device.

[0060] The present invention will be described in detail below through examples, but this does not limit the invention. In the following examples, unless otherwise specified, the experimental instruments, reagents and raw materials involved are all commercially available products, and the reagents are all analytical grade products.

[0061] Unless otherwise specified, in the following examples, the concentrations of hydrofluoric acid are 55 wt%, sulfuric acid is 98 wt%, hydrochloric acid is 36 wt%, nitric acid is 68 wt%, ammonium bifluoride is 95 wt%, phosphoric acid is 85 wt%, and glucose is a 95 wt% aqueous solution of glucose.

[0062] Example 1

[0063] This embodiment illustrates that the low-haze glass of the present invention is prepared according to the process parameters in Table 1 and the method described below.

[0064] The method for preparing low-haze glass includes:

[0065] Pretreatment: Coat the tin side of the aluminosilicate glass with a 50μm UV adhesive film; the thickness of the aluminosilicate glass is 1.1mm; the thickness of the tin-impregnated layer on the tin side of the aluminosilicate glass is 10μm;

[0066] Step 1: Polish the aluminosilicate glass in the presence of a polishing solution to obtain intermediate product I;

[0067] Step 2: The intermediate product I is etched in etching solution I to obtain intermediate product II;

[0068] Step 3: The intermediate product II is etched a second time in etching solution II to obtain the low-haze glass.

[0069] Unless otherwise specified, the remaining examples follow a similar process to Example 1, except that the process parameters used in each example are different, as detailed in Table 1.

[0070] Table 1

[0071]

[0072]

[0073] Example 7

[0074] This embodiment follows a similar process to Embodiment 1. The difference is that in this embodiment, the polishing conditions in step one are: a polishing rate of 4.5 μm / min; and, based on the total mass of the polishing solution, the polishing solution contains 8 wt% hydrofluoric acid, 6 wt% sulfuric acid, 5 wt% hydrochloric acid, 7 wt% phosphoric acid, and 74 wt% water.

[0075] Everything else is the same as in Example 1.

[0076] Low-haze glass S7 was prepared.

[0077] Comparative Example 1

[0078] This comparative example uses a similar process to Example 1. The difference is that in this comparative example, in step one, the polishing solution contains 5 wt% hydrofluoric acid, 3 wt% acetic acid (concentration of 99 wt%), and 92 wt% water, based on the total mass of the polishing solution.

[0079] Everything else is the same as in Example 1.

[0080] Low-haze glass DS1 was prepared.

[0081] Comparative Example 2

[0082] This comparative example uses a similar process to Example 1. The difference is that in this comparative example, in step two, the first etching condition is: the etching thickness is 4μm.

[0083] Everything else is the same as in Example 1.

[0084] Low-haze glass DS2 was prepared.

[0085] Comparative Example 3

[0086] This comparative example uses a similar process to Example 1. The difference is that in this comparative example, in step three, the second etching condition is: the etching thickness is 4 μm.

[0087] Everything else is the same as in Example 1.

[0088] Low-haze glass DS3 was prepared.

[0089] Comparative Example 4

[0090] This comparative example follows a similar process to Example 1, except that in step one, physical polishing is used for polishing. Specifically, the physical polishing steps are as follows:

[0091] In the presence of polishing fluid, aluminosilicate glass is polished to obtain intermediate product I; the polishing conditions include: polishing thickness of 15μm, polishing rate of 3μm / min, polishing temperature of 30-38℃, and pH value of 3-9.

[0092] The polishing fluid is a polishing fluid (model VK-Ce02W, purchased from Xuancheng Jingrui New Materials Co., Ltd.) and water in a mass ratio of 1:1.

[0093] Everything else is the same as in Example 1.

[0094] Low-haze glass DS4 was prepared.

[0095] Test case

[0096] 1. Gloss uniformity test: The gloss of the etched surface of the product is tested using a triangular gloss meter. For each product, taking 10.5-inch as an example, 9 points are measured. The uniformity is the CPK value of the 9 test points. The higher the value, the better.

[0097] 2. Haze value: The haze of the product is measured using a haze transilluminator;

[0098] 3. Roughness difference: The roughness of the etched surface of the product is tested using a Mitutoyo roughness measuring instrument. For each product, taking a 10.5-inch piece as an example, at least 6 points are measured, and the difference between the maximum and minimum values ​​is calculated. The smaller the value, the better.

[0099] 4. Product yield: The product yield is mainly determined by first confirming that the haze value parameter meets the requirements (not higher than 35) through instrument measurement, and then visually inspecting the appearance for obvious spot / line / block discoloration and scratches. If there are no defects, the product is considered qualified. Each example and comparative example uses the corresponding preparation method to prepare 100 pieces of glass. Product yield = number of qualified products / 100.

[0100] The performance of the low-haze glass obtained in the examples and comparative examples was tested using the above test methods, and the results are shown in Table 2.

[0101] Table 2

[0102]

[0103]

[0104] As can be seen from the results in Table 2, the low-haze glass prepared by the method provided by the present invention not only meets the market demand for low haze, but also has better gloss uniformity and roughness, resulting in a higher product yield and effectively reducing input costs.

[0105] The present invention provides an exemplary embodiment 1 ( Figure 1 ) and Example 3 ( Figure 2 The grain surface images of the low-haze glass prepared at different magnifications further illustrate that the method provided by this invention can obtain products with different roughness and haze values, as well as high optical uniformity and yield, meeting the needs of different markets while ensuring product quality.

[0106] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing low-haze glass, characterized in that, The method includes: (1) Polishing aluminum-silicon glass in the presence of a polishing solution to obtain intermediate product I; the polishing conditions include: a polishing thickness of 10-20 μm; the polishing solution is selected from at least one of solution A, solution B and solution C; (2) The intermediate product I is etched in etching solution I to obtain intermediate product II; the conditions for the first etching include: the etching thickness is 1-2 μm; the difference in the height of the unevenness within any 40 μm × 40 μm range on the surface of the intermediate product II is not greater than 0.25 μm; (3) The intermediate product II is subjected to a second etching in etching solution II to obtain the low haze glass; the conditions for the second etching include: etching thickness of 30-80 μm; Based on the total mass of solution A, solution A contains 2-8 wt% hydrofluoric acid, 1-7 wt% sulfuric acid, 1-5 wt% hydrochloric acid, 1-5 wt% nitric acid and 75-95 wt% water; Based on the total mass of solution B, solution B contains 3-10 wt% ammonium bifluoride, 10-30 wt% sulfuric acid and 60-87 wt% water; Based on the total mass of solution C, solution C contains 2-13 wt% hydrofluoric acid, 1-7 wt% sulfuric acid, 1-5 wt% hydrochloric acid, 3-8 wt% phosphoric acid and 71-93 wt% water; In step (2), based on the total mass of the etching solution I, the etching solution I contains 18-26 wt% ammonium bifluoride, 7-11 wt% citric acid, 2-5 wt% barium sulfate, 2-6 wt% bentonite, 8-15 wt% ferric chloride, 8-15 wt% potassium nitrate, 5-9 wt% potassium fluoride, 3-6 wt% hydrofluoric acid and 7-44 wt% water; In step (3), the etching solution II is selected from at least one of solution C and solution D; based on the total mass of solution D, solution D contains 5-20 wt% hydrofluoric acid, 2-15 wt% sulfuric acid, 5-20 wt% ammonium bifluoride, 1-5 wt% glucose and 40-87 wt% water.

2. The method according to claim 1, characterized in that, In step (1), the polishing conditions also include a polishing rate of 2-4 μm / min; And / or, the polishing solution is a C solution.

3. The method according to claim 1 or 2, characterized in that, The thickness of the aluminosilicate glass is 0.3-1.8 mm; And / or, the thickness of the tin-impregnated layer on the tin side of the aluminosilicate glass is not higher than 15 μm.

4. The method according to claim 3, characterized in that, The thickness of the aluminosilicate glass is 1.0-1.5 mm.

5. The method according to claim 1 or 2, characterized in that, The method further includes coating the tin side of the aluminosilicate glass with a protective material before performing step (1).

6. The method according to claim 5, characterized in that, The protective material is selected from at least one of acid-resistant ink, UV-curable ink, and UV film.

7. The method according to claim 6, characterized in that, The thickness of the protective coating is 15-70 μm.

8. The low-haze glass prepared by the method according to any one of claims 1-7.

9. The application of the low-haze glass according to claim 8 in a display device.

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