High-strength coverglass and preparation method therefor

Abstract

Disclosed are a high-strength coverglass and a preparation method therefor, belonging to the technical field of glass manufacturing. The high-strength coverglass is prepared from the following raw materials: 56-65wt% SiO2, 15-22.5wt% Al2O3, 3-9wt% MgO, 9-15wt% Na2O, 3-6wt% K2O, 0.2-1.2wt% CaO, 0.2-1.2wt% SrO, 0.5-1.8wt% ZrO2, and 0.1-0.5wt% SnO. According to a specific proportion, the raw materials are placed into a mortar and mixed uniformly, then poured into a platinum crucible, which is then placed into a resistance-type high-temperature box for melting; once melting and fining is complete, the mixture is poured into a mold for molding, annealing, and cooling. The disclosed coverglass is high in strength, has a high elastic modulus, improved fragmentation resistance, and high light transmittance, and the properties of thereof are suited to float process production of coverglass that can be used in display products.

Description

High-strength cover glass and preparation method thereof Technical Field

[0001] The present invention belongs to the technical field of glass manufacturing, and in particular relates to a high-strength cover glass and a preparation method thereof. Background Art

[0002] With the development of the high-tech industry, electronic products have become an integral part of human life. Glass cover plates protect display panels, and aluminosilicate glass, with its high strength and ease of post-processing, is the optimal material for these covers. As display devices become thinner and lighter, ultra-thin glass can amplify the negative impact of defects on glass strength, severely impacting product lifespan and durability. Therefore, high-strength ultra-thin cover glass is particularly important. To achieve this high strength, high-aluminum glass is generally used. While a high Al2O3 content improves glass strength, it also results in higher viscosity and higher melting temperatures, typically above 1640°C. This places higher demands on the refractory materials in the glass furnace and tin bath. Certain batch materials that are susceptible to corrosive refractory materials can cause greater damage to the furnace and complicate molding. Therefore, developing high-strength cover glass suitable for float glass production is crucial to improving the drop resistance of end products and meeting the current demand for high-end cover glass materials.

[0003] Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide a high-strength cover glass and a preparation method thereof. The glass of the present invention has the characteristics of high strength, high elastic modulus, better anti-shattering ability and high light transmittance, and the preparation process of the glass with this chemical composition is simple and easy to implement.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A high-strength cover glass is made of the following raw materials in percentage by weight: SiO2 56-65wt%, Al2O3 15-22.5wt%, MgO 3-9wt%, Na2O 9-15wt%, K2O 3-6wt%, CaO 0.2-1.2wt%, SrO 0.2-1.2wt%, ZrO2 0.5-1.8wt%, and SnO 0.1-0.5wt%; wherein Al2O3:SiO2=1:2.5-4.5, ∑RO (the total content of MgO, CaO, and SrO)=3.5-11.5wt%, and MgO:CaO:SrO=4-10:1:1.

[0007] Furthermore, the high-strength cover glass is made of the following raw materials in weight percentage: SiO2 57-61wt%, Al2O3 15-19wt%, MgO 3-7wt%, Na2O 11-14.5wt%, K2O 4-6wt%, CaO 0.5-0.8wt%, SrO 0.5-0.8wt%, ZrO2 0.5-1wt%, SnO 0.1-0.5wt%; wherein Al2O3:SiO2=1:3-4, ∑RO(MgO,CaO,SrO)

[0008] =4-8.5wt%, MgO:CaO:SrO=4~8:1:1.

[0009] A method for preparing high-strength cover glass comprises the following steps:

[0010] (1) weighing raw materials according to the above weight percentages, then placing all the raw materials in a mortar and mixing them evenly to prepare a glass batch;

[0011] (2) Pour the mixed glass batch into a platinum crucible, and then place it in a resistance high temperature box and melt it at 1580-1630°C for 3-5 hours;

[0012] (3) After the ingredients are melted and clarified, they are poured into a mold and, after forming, transferred to an annealing furnace at a temperature of 580-620°C for annealing for 25-35 minutes to eliminate residual stress in the glass structure;

[0013] (4) After annealing, the glass is cooled to room temperature in the furnace, and a cover glass with high strength, high elastic modulus, better anti-shattering ability and high light transmittance is obtained.

[0014] The SiO2 content in the glass of the present invention is between 56 and 65 wt%. SiO2 serves as a skeleton for the glass, which can increase the strain point and reduce the thermal expansion coefficient. However, when the SiO2 content is high, the high-temperature viscosity of the glass increases and the crystallization tendency increases. When the SiO2 content is too low, the chemical corrosion resistance decreases.

[0015] The Al2O3 content in the glass of the present invention is 15-22.5wt%. Al2O3 can increase Young's modulus, inhibit phase separation of glass, reduce thermal expansion coefficient, and increase strain point. However, too high a content is likely to cause crystallization and increase liquidus temperature.

[0016] The alkali metals, such as Na2O and K2O, in the glass of the present invention provide excess oxygen ions, breaking the network of silicon, the main structural element, to form non-bridging oxygen. They act as fluxing agents in glassmaking and significantly influence both the formation of glass and the clarification process of the glass liquid.

[0017] The content of MgO in the glass of the present invention is 3 to 9 wt %. MgO is a component that reduces high-temperature viscosity and improves solubility, and is a component that significantly increases Young's modulus among alkaline earth metal oxides.

[0018] The content of CaO in the glass of the present invention is 0.2-1.2 wt %. CaO can significantly improve the chemical stability and mechanical strength of the glass, and is a component that reduces high-temperature viscosity and improves solubility.

[0019] The content of SrO in the glass of the present invention is 0.2-1.2 wt %. SrO, as a co-solvent, can prevent crystallization. However, excessive SrO will increase the density of the glass, making the weight too high.

[0020] The ZrO2 content in the glass of the present invention is 0.5-1.8wt%. During the glass ion exchange process, it can increase the component of the compressive stress on the glass surface, improve the glass hardness and Young's modulus, improve the weather resistance and stability of the glass, and at the same time has a certain effect of strengthening the glass network structure. However, too much ZrO will make the glass difficult to melt and increase the possibility of cracking in the glass due to self-indentation.

[0021] The content of SnO in the glass of the present invention is 0.1-0.5 wt%. SnO acts as a clarifier, so that the formula does not contain harmful substances such as arsenic and antimony, thus meeting environmental protection requirements.

[0022] Beneficial effects of the present invention:

[0023] 1. Different from the common float high-aluminum glass, the glass of the present invention has a lower melting temperature, ranging from 1590 to 1610°C. 2. The cover glass produced by the present invention has an elastic modulus of ≥78GPa, a hardness of ≥610MPa, a strain point higher than 630°C, and a density of ρ≤2.48g / cm 3 The visible light transmittance can reach more than 91% in the wavelength of 377nm~1000nm, and it has excellent comprehensive performance. 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 embodiments described 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 making any creative efforts shall fall within the scope of protection of the present invention.

[0025] The cover glasses of Examples 1-5 were prepared according to the following steps:

[0026] (1) Weigh the raw materials according to the mass percentage in Table 1

[0027] (2) Then, all the raw materials are put into a mortar and mixed evenly to prepare a glass batch;

[0028] (3) Pour the mixed glass batch into a platinum crucible, then place it in a resistance high temperature box and melt it at 1630°C for 3 hours;

[0029] (4) After the ingredients are melted and clarified, they are poured into a mold and, after forming, transferred to an annealing furnace at a temperature of 600°C for 30 minutes to eliminate residual stress in the glass structure;

[0030] (5) After annealing, the glass is cooled to room temperature in the furnace and then cut, ground, and polished to obtain the cover glass.

[0031] Table 1 Raw material components of Examples 1-5

[0032] The cover glasses obtained in Examples 1-6 were subjected to performance tests, and the results are shown in Table 2 below:

[0033] Table 2 Glass performance indicators obtained in Examples 1-5

[0034] As can be seen from the data in Table 2 above, the cover glass obtained by the present invention has an elastic modulus ≥78 GPa, a hardness ≥610 MPa, a strain point higher than 630°C, and a density ρ <2.48 g / cm3; and a visible light transmittance of more than 91% at a wavelength of 377 nm to 1000 nm, with excellent overall performance.

[0035] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0036] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A high-strength cover glass, characterized in that: The invention is made of the following raw materials in weight percentage: SiO2 56-65wt%, Al2O3 15-22.5wt%, MgO 3-9wt%, Na2O 9-15wt%, K2O 3-6wt%, CaO 0.2-1.2wt%, SrO 0.2-1.2wt%, ZrO2 0.5-1.8wt%, SnO 0.1-0.5wt%.

2. The high-strength cover glass according to claim 1, characterized in that: Al2O3:SiO2=1:2.5~4.5, the total content of MgO, CaO and SrO is 3.5-11.5wt%, MgO:CaO:SrO=4~10:1:

1.

3. The high-strength cover glass according to claim 1, characterized in that: The invention is made of the following raw materials in weight percentage: SiO2 57-61wt%, Al2O3 15-19wt%, MgO 3-7wt%, Na2O 11-14.5wt%, K2O 4-6wt%, CaO 0.5-0.8wt%, SrO 0.5-0.8wt%, ZrO2 0.5-1wt%, SnO 0.1-0.5wt%.

4. The high-strength cover glass according to claim 3, characterized in that: Al2O3:SiO2=1:3~4, the total content of MgO, CaO and SrO is =4-8.5wt%, MgO:CaO:SrO=4~8:1:

1.

5. A method for preparing a high-strength cover glass according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) weighing raw materials according to the above weight percentages, then putting all the raw materials into a mortar and mixing them evenly to prepare a glass batch; (2) pouring the mixed glass batch into a platinum crucible, and then placing it in a resistance high temperature box and melting it at 1580-1630° C. for 3-5 hours; (3) After the ingredients are melted and clarified, they are poured into a mold, and after forming, they are transferred to an annealing furnace at a temperature of 580-620°C for annealing for 25-35 minutes to eliminate residual stress in the glass structure; (4) After the annealing is completed, the glass is cooled to room temperature in the furnace to obtain the cover glass.

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