Glass composition, chemically strengthened glass, preparation method of chemically strengthened glass and electronic equipment

Abstract

The invention discloses a glass composition, chemically strengthened glass, a preparation method of the chemically strengthened glass and electronic equipment, and belongs to the technical field of glass. According to the invention, the mass ratio of SiO2 to Al2O3 to B2O3 to P2O5 to Li2O to Na2O to K2O to CaO to SrO in the glass composition is adjusted to meet the following conditions: 1.67 < = A = (SiO2 + B2O3) / (P2O5 + Al2O3) < = 2.91, 0.37 < = B = (Li2O + K2O) / Na2O < = 2.64 and 3.03 < = C = (Al2O3 + P2O5 + CaO + SrO) / (Li2O + Na2O + K2O) < = 3.76, so that the high-temperature viscosity of the glass can be reduced, the crystallization is inhibited, the stress relaxation problem caused in the long-time or high-temperature chemical strengthening process of the glass can be improved, the ion exchange speed and depth during chemical strengthening can be promoted, the chemical strengthening effect can be improved, and the service life of and the mechanical property of the chemically strengthened glass is enhanced.

Description

Technical Field

[0001] This invention relates to the field of glass technology, and more particularly to a glass composition, chemically strengthened glass, a method for preparing the same, and electronic equipment. Background Technology

[0002] With the development of communication technology, the use of glass for the front and back covers of mobile communication devices (such as mobile phones and smartwatches) has become an inevitable trend. This places higher demands on the glass materials used to protect the display devices. Typically, superior physical and mechanical properties are required, such as high mechanical strength, high Young's modulus, high chemical temperature resistance, and thinness, to prevent screen damage caused by external factors such as impacts, drops, scratches, and pressure during use. Traditional soda-lime silicate glass cannot meet the above requirements; its high strength, high deformation resistance, and scratch resistance are poor. Therefore, there is a need to find glass with higher strength, higher hardness, lower brittleness, scratch resistance, and deformation resistance. Firstly, one can start with the glass system and composition. By adjusting the composition and structure of the glass, the elastic modulus, hardness, and brittleness can be improved, thereby obtaining glass with high impact resistance, high scratch resistance, and high deformation resistance. For example, lithium aluminum silicate glass has the advantages of high strength and high hardness, making it suitable as cover glass for electronic products.

[0003] However, there are many problems in the strengthening process of lithium aluminum silicate glass. For example, lithium aluminum silicate glass requires secondary ion exchange. During the second chemical strengthening, stress relaxation is prone to occur, leading to technical problems such as poor mechanical properties due to drop difference. Summary of the Invention

[0004] The main objective of this invention is to provide a glass composition, chemically strengthened glass, a method for preparing the same, and an electronic device, thereby solving the technical problem of stress relaxation in glass caused by high-temperature chemical strengthening during the chemical strengthening stage.

[0005] To achieve the above objectives, the present invention provides a glass composition comprising, by weight percentage, the following components: SiO2: 50%–60%, Al2O3: 20%–30%, B2O3: 1%~6%, P2O5: 0.5%~5%, Li2O: 2%~6.5%, Na2O: 3%~7%, K2O: 0.1%~1%, CaO: 0.1%–4%, SrO: 0.1%~4%, Satisfy: 1.67 ≤ A = (SiO2 + B2O3) / (P2O5 + Al2O3) ≤ 2.91, 0.37 ≤ B = (Li2O + K2O) / Na2O ≤ 2.64, 3.03 ≤ C = (Al2O3 + P2O5 + CaO + SrO) / (Li2O + Na2O + K2O) ≤ 3.76.

[0006] In some embodiments of the present invention, calculated by mass percentage, the glass composition further comprises an auxiliary agent: 0 - 1%, and the auxiliary agent comprises at least one of MgO, TiO2, ZnO, Y2O3.

[0007] The present invention also provides a chemically strengthened glass, and the chemically strengthened glass comprises the glass composition as described above.

[0008] In some embodiments of the present invention, define the stress relaxation resistance index of the chemically strengthened glass as F, and satisfy: 1.97 ≤ F = 100×(ρpost - ρpre)×(CS - CS-Na) / (DOL-Na - DOL-K).

[0009] In some embodiments of the present invention, satisfy: 1.97 ≤ F = 100×(ρpost - ρpre)×(CS - CS-Na) / (DOL-Na - DOL-K) ≤ 4.43.

[0010] In some embodiments of the present invention, the chemically strengthened glass satisfies: The surface stress value CS of the chemically strengthened glass ≥ 1000 MPa; and / or, The surface stress CS-Na generated after ion exchange of sodium ions and lithium ions in the chemically strengthened glass is ≥ 300 MPa; and / or, The ion exchange depth DOL-Na of sodium ions and lithium ions in the chemically strengthened glass is ≥ 120 μm; and / or, The ion exchange depth DOL-K of potassium ions and sodium ions in the chemically strengthened glass is ≥ 8.7 μm.

[0011] In some embodiments of the present invention, the thickness of the chemically strengthened glass is 0.08 mm - 1.5 mm.

[0012] The present invention also provides a preparation method of a chemically strengthened glass, comprising the following steps: Weigh glass raw materials according to the composition of the glass composition as described above; Melt, clarify, homogenize, form, and anneal the glass raw materials to obtain a glass substrate; The glass substrate is chemically strengthened to obtain the chemically strengthened glass described above.

[0013] In some embodiments of the present invention, the chemical enhancement treatment includes a first enhancement treatment and a second enhancement treatment; The first step of the strengthening treatment includes a first molten salt, which includes NaNO3. The first strengthening temperature of the first step of the strengthening treatment is 430℃~480℃, and the first strengthening temperature is 1h~3h. The second strengthening treatment includes a second molten salt, which includes KNO3. The second strengthening temperature of the second strengthening treatment is 400℃~450℃, and the second strengthening time is 1h~3h.

[0014] The present invention also provides an electronic device, characterized in that the electronic device comprises chemically strengthened glass as described above.

[0015] The beneficial effects that this invention can achieve are: This invention employs a specific ratio combination of SiO2, Al2O3, B2O3, P2O5, Li2O, Na2O, K2O, CaO, and SrO in a glass composition, adjusting the proportions to satisfy 1.67 ≤ A = (SiO2 + B2O3) / (P2O5 + Al2O3) ≤ 2.91, 0.37 ≤ B = (Li2O + K2O) / Na2O ≤ 2.64, and 3.03 ≤ C = (Al2O3 + P2O5 + CaO + SrO) / (Li2O + Na2O + K2O) ≤ 3.76. This reduces the high-temperature viscosity of the glass, improves its crystallization performance at high temperatures, reduces the risk of crystallization, raises the strain point of the glass, enhances its thermal properties, mitigates stress relaxation issues caused by prolonged or high-temperature chemical strengthening, and promotes ion exchange rates during chemical strengthening, thereby promoting the growth of Li... + Na + K + The ion exchange between components enhances the CS-K, CS-Na, DOL, and DOL-K content of chemically strengthened glass, thereby significantly improving the chemical strengthening effect and effectively enhancing its mechanical properties. Furthermore, by optimizing the composition ratio of the glass composition, this invention enables the glass system to be mass-produced using various processes such as float glass, overflow glass, rolling glass, and downdraw glass.

[0016] The chemically strengthened glass prepared by this invention has excellent properties and can be used as a front cover or back cover for touch screens or other electronic smart terminals. It can also be applied to photovoltaic power generation devices, automotive windows, automotive protective glass, and pharmaceutical glass containers or primary packaging. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of a method for preparing chemically strengthened glass according to the present invention.

[0019] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] In this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination should be considered non-existent and not within the scope of protection claimed by this invention.

[0023] This invention provides a glass composition, which, based on mass percentage, comprises the following components: SiO2: 50%–60%, Al2O3: 20%–30%, B2O3: 1%~6%, P2O5: 0.5%~5%, Li2O: 2%~6.5%, Na2O: 3%~7%, K2O: 0.1%~1%, CaO: 0.1-4%, SrO: 0.1–4%, satisfy: 1.67≤A=(SiO2+B2O3) / (P2O5+Al2O3)≤2.91, 0.37≤B=(Li2O+K2O) / Na2O≤2.64, 3.03≤C=(Al2O3+P2O5+CaO+SrO) / (Li2O+Na2O+K2O)≤3.76.

[0024] This invention employs a specific ratio combination of SiO2, Al2O3, B2O3, P2O5, Li2O, Na2O, K2O, CaO, and SrO in a glass composition, adjusting the proportions to satisfy 1.67 ≤ A = (SiO2 + B2O3) / (P2O5 + Al2O3) ≤ 2.91, 0.37 ≤ B = (Li2O + K2O) / Na2O ≤ 2.64, and 3.03 ≤ C = (Al2O3 + P2O5 + CaO + SrO) / (Li2O + Na2O + K2O) ≤ 3.76. This reduces the high-temperature viscosity of the glass, improves its crystallization performance at high temperatures, reduces the risk of crystallization, raises the strain point of the glass, enhances its thermal properties, mitigates stress relaxation issues caused by prolonged or high-temperature chemical strengthening, and promotes ion exchange rates during chemical strengthening, thereby promoting the growth of Li... + Na + K + The ion exchange between them enhances the CS-K, CS-Na, DOL, and DOL-K of chemically strengthened glass, thereby significantly improving the chemical strengthening effect and effectively enhancing the mechanical properties of chemically strengthened glass.

[0025] Furthermore, the present invention also provides a chemically strengthened glass, comprising the above-described glass composition, wherein: The chemically strengthened glass of this invention contains SiO2, which serves as the main component of the glass network structure. If the SiO2 content is low, glass formation is difficult, and the strain point of the glass decreases while the coefficient of thermal expansion increases, easily leading to poor mechanical properties and chemical stability. Increasing the SiO2 content can improve the mechanical strength and stability of the glass. However, if the SiO2 content is too high, the glass is difficult to melt at high temperatures, which will exacerbate the erosion of the furnace refractory materials. Therefore, it is necessary to control its content within a suitable range. Thus, this invention controls the SiO2 content to be 50%–60%, which can be 50%, 52%, 55%, 58%, 60%, etc.

[0026] The chemically strengthened glass of this invention contains Al2O3. The non-bridging oxygen in the glass structure can form aluminum-oxygen tetrahedra with Al. The volume of aluminum-oxygen tetrahedra is larger than that of silicon-oxygen tetrahedra, making it easier to create larger gaps in the glass structure, which is beneficial for ion exchange, thereby improving the glass's scratch resistance and drop resistance. However, when the Al2O3 content is too high, the glass is difficult to melt at high temperatures; when the Al2O3 content is too low, the glass is prone to crystallization, which is not conducive to forming and results in lower mechanical strength. Considering all factors, this invention controls the Al2O3 content to be 20%–30%, which can be 20%, 22%, 25%, 26%, 28%, 29%, 30%, etc.

[0027] The chemically strengthened glass of this invention contains B2O3, which can lower the melting temperature of the glass and improve the damage resistance of the resulting glass products. At high temperatures, B2O3 exists in a trigonal form, thereby reducing the high-temperature viscosity of the glass. At low temperatures, B2O3 exists in a tetrahedral form within the glass structure, which is beneficial for strengthening the glass network structure and improving its brittleness, toughness, and light transmittance. Therefore, this invention controls the B2O3 content to be 1%–6%, which can be 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, etc.

[0028] The chemically strengthened glass of this invention contains P2O5, which can induce changes in the network structure of the glass, specifically, the replacement of SiO2 in the glass with aluminum phosphate (AlPO4). Compared to silicon-oxygen tetrahedra, aluminum phosphate (AlPO4) has a larger volume and does not disrupt the overall network structure of the glass, thereby increasing the ion exchange rate during ion strengthening and improving the glass's damage resistance. However, excessively high P2O5 content will reduce the stability of the glass. Therefore, considering all factors, this invention controls the P2O5 content to be 0.5%~5%, which can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, etc.

[0029] The chemically strengthened glass of this invention contains Li₂O, Na₂O, and K₂O. K₂O, Li₂O, and Na₂O can form a mixed alkali effect, which can reduce the high-temperature viscosity of the glass and reduce its tendency to crystallize. Simultaneously, Li₂O, Na₂O, and K₂O are the main exchange ions in the chemical strengthening process. The presence of Li ions is beneficial for secondary chemical strengthening, creating compressive stress on the glass surface, thereby improving the strength of the glass products. However, the Li₂O content should not be too high. If the content is too high, it will severely corrode the refractory materials, easily cause crystallization, and lead to poor glass stability. Conversely, when the Na₂O and K₂O contents are high, it will affect the rate of chemical strengthening of the glass, increase the coefficient of thermal expansion, and reduce the mechanical properties of the glass. Taking all factors into consideration, the present invention controls the Li2O content to be 2% to 6.5%, which can be 2%, 2.5%, 2.8%, 3%, 3.5%, 3.8%, 4%, 4.2%, 4.5%, 4.8%, 5%, 5.2%, 5.4%, 5.5%, 5.8%, 5.9%, 6%, 6.5%, etc.; the Na2O content to be 3% to 7%, which can be 3%, 3.3%, 3.5%, 3.8%, 3.9%, 4%, 4.2%, 4.5%, 4.8%, 5%, 5.5%, 6%, 6.5%, 7%, etc.; and the K2O content to be 0.1% to 3%, which can be 0.1%, 1.5%, 2%, 2.5%, 3%, etc.

[0030] The chemically strengthened glass of this invention contains CaO. The addition of CaO helps to lower the high-temperature melting temperature of the glass, regulate the properties of the glass forming material, and reduce the tendency for high-temperature crystallization. The radius of Ca ions is close to that of Na ions, which can regulate the exchange rate between Li and Na ions during ion exchange, further improving the CS-Na stress intensity and depth after glass strengthening. Simultaneously, CaO raises the strain point of the glass, thereby mitigating stress relaxation caused by prolonged or high-temperature chemical strengthening. Therefore, considering all factors, the CaO content of this invention is controlled at 0.1% to 4%, and can be 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.2%, 3.5%, 3.8%, 4%, etc.

[0031] The chemically strengthened glass of this invention contains SrO, which can improve the glass's meltability. Controlling the SrO content in the glass within a suitable range is beneficial for improving the glass's thermal and chemical stability and chemical strengthening properties. However, if the SrO content is high, it may result in a higher glass density, a higher coefficient of thermal expansion, and poorer glass stability, which is detrimental to glass production and processing. Therefore, considering all factors, the SrO content of this invention is 0.1% to 4%, and can be 0.1%, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.2%, 3.5%, 3.8%, 4%, etc.

[0032] In some embodiments, the chemically strengthened glass of the present invention further includes 0-1% additives by weight percentage. The additives include at least one of K2O, MgO, TiO2, ZnO, and Y2O3, which are beneficial for reducing the melting temperature of the glass, have the function of regulating the properties of the glass forming material, and can also regulate the ion exchange during the chemical strengthening process.

[0033] In some embodiments, the glass composition of the chemically strengthened glass of the present invention further includes a clarifying agent, which includes any two or more of sodium chloride, sodium sulfate, tin oxide, cerium oxide, and NaNO3. The amount of clarifying agent added is 0.1% to 0.3% of the mass of the glass raw materials required for the composition of the glass composition, and may be 0.2%.

[0034] In the chemically strengthened glass of this invention, SiO2 forms the glass network structure. When SiO2 is replaced by AlO4 or AlPO4, AlO4 and AlPO4 have a larger volume compared to the silicon-oxygen tetrahedrons in the glass network structure, which can improve the ion exchange rate during subsequent glass strengthening and reduce the high-temperature viscosity of the glass. B2O3 can enter the glass network structure in the form of trihedrons or tetrahedrons. Under high-temperature conditions rich in aluminum and phosphorus, B easily transforms into larger tetrahedrons, which can replace SiO2 together with AlO4 and AlPO4, making the glass network more open. This reduces the high-temperature viscosity of the glass, decreases the risk of crystallization, and promotes ion exchange. Therefore, this invention adjusts the relationship between SiO2, B2O3, P2O5, and Al2O3, controlling 1.67≤A=(SiO2+B2O3) / (P2O5+Al2O3)≤2.91, that is, A can be 1.67, 1.70, 1.71, 1.73, 1.75, 1.77, 1.79, 2.00, 2.10, 2.20, 2.30, 2.40, 2.50, 2.55, 2.60, 2.65, 5.70, 2.75, 2.80, 2.85, 2.87, 2.90, 2.91, etc., thereby reducing the high-temperature viscosity of glass, reducing the risk of crystallization, improving glass forming, promoting the ion exchange rate during chemical strengthening, and enhancing the chemical strengthening effect, thus enhancing the mechanical properties of glass.

[0035] In the chemically strengthened glass of this invention, the value of B is controlled to be 0.3 ≤ B = (Li₂O + K₂O) / Na₂O ≤ 2.64, i.e., the value of B can be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.5, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.55, 2.56, 2.58, 2.59, 2.60, 2.61, 2.62, 2.63, 2.64, etc., which is beneficial to Li + Na + K +The exchange between them generates a sufficient ion exchange depth, while simultaneously enhancing the CS-K, CS-Na, DOL, and DOL-K values ​​of the chemically strengthened glass. The synergistic effect of these values ​​and the A value further improves the chemical strengthening effect of the glass and enhances its mechanical properties.

[0036] In the chemically strengthened glass of this invention, controlling 3.03≤(Al2O3+P2O5+CaO+SrO) / (Li2O+Na2O+K2O)≤3.76, i.e., the C value can be 3.03, 3.05, 3.09, 3.10, 3.12, 3.15, 3.18, 3.20, 3.23, 3.25, 3.29, 3.30, 3.40, 3.50, 3.60, 3.65, 3.68, 3.69, 3.70, 3.71, 3.72, 3.73, 3.74, 3.75, 3.76, etc., can improve the crystallization performance of the glass at high temperatures, increase the strain point of the glass, and enhance the thermal properties of the glass. This improves the stress relaxation problem caused by chemical strengthening of the glass over a long period of time or at high temperatures. In synergy with the above-mentioned A and B values, the chemical strengthening effect of the glass is improved, and the mechanical properties of the glass are enhanced.

[0037] This invention employs a specific ratio combination of the components SiO2, Al2O3, B2O3, P2O5, Li2O, Na2O, K2O, CaO, and SrO in a glass composition, adjusting them to satisfy the following conditions: 1.67 ≤ A = (SiO2 + B2O3) / (P2O5 + Al2O3) ≤ 2.91, 0.37 ≤ B = (Li2O + K2O) / Na2O ≤ 2.64, and 3.03 ≤ C = (Al2O3 + P2O5 + CaO + SrO) / (Li2O + Na2O + K2O) ≤ 3.76. By controlling the values ​​of A, B, and C, the glass works synergistically to reduce its high-temperature viscosity, improve its crystallization performance at high temperatures, reduce the risk of crystallization, increase its strain point, enhance its thermal properties, mitigate stress relaxation issues caused by prolonged or high-temperature chemical strengthening, and promote ion exchange rates during chemical strengthening, thereby promoting the growth of Li... + Na + K + The ion exchange between them enhances the CS-K, CS-Na, DOL, and DOL-K of chemically strengthened glass, thereby significantly improving the chemical strengthening effect and effectively enhancing the mechanical properties of chemically strengthened glass.

[0038] The chemically strengthened glass prepared by this invention has excellent properties and can be used as a front cover or back cover for touch screens or other electronic smart terminals. It can also be applied to photovoltaic power generation devices, automotive windows, automotive protective glass, and pharmaceutical glass containers or primary packaging.

[0039] In some embodiments, calculated by mass percentage, the components of the glass composition in the chemically strengthened glass further include an auxiliary agent: 0 to 1%, and the auxiliary agent includes at least one of MgO, TiO2, ZnO, and Y2O3.

[0040] The chemically strengthened glass component of the present invention contains lithium aluminosilicate. As a lithium aluminosilicate glass, during chemical strengthening, the first-step sodium-lithium ion replacement can generate CS-Na and DOL-Na, providing a stress exchange layer and stress depth for resisting ball drop impact. During the second-step potassium-sodium ion replacement process, on the one hand, the stress value generated during the first-step sodium-lithium replacement will undergo stress relaxation, CS-Na decreases, and DOL-Na increases; the potassium-sodium replacement generates a greater surface compressive stress value CS-K and a denser DOL-K ion exchange layer; on the other hand, different density differences are generated before and after ion exchange, which is likely to bring differences in strengthening performance. Based on the above findings, the chemical strengthening performance of the glass has a significant relationship with F = 100×(ρafter - ρbefore)×(CS - CS-Na) / (DOL-Na - DOL-K). In the above relational expression, ρafter refers to the density of the chemically strengthened glass after chemical strengthening, and ρbefore refers to the density of the chemically strengthened glass before chemical strengthening, that is, the density of the glass substrate obtained after forming. When controlling the F value within a certain range: 1.97 ≤ F = 100×(ρafter - ρbefore)×(CS - CS-Na) / (DOL-Na - DOL-K), the stress relaxation problem generated during the high-temperature chemical strengthening of the glass can be further improved.

[0041] In some embodiments, control 1.97 ≤ F = 100×(ρafter - ρbefore)×(CS - CS-Na) / (DOL-Na - DOL-K) ≤ 4.43, that is, the F value can be 1.97,​​​​​In some embodiments, the surface stress CS-Na generated in the chemically strengthened glass after ion exchange between sodium and lithium ions is ≥300 MPa. CS-Na refers to the compressive stress value on the surface of the chemically strengthened glass, which is mainly affected by the replacement of lithium ions in the glass by sodium ions in the molten salt. Preferably, CS-Na is 300~400 MPa, more preferably 300~350 MPa, and CS-Na can be 300 MPa, 310 MPa, 320 MPa, 330 MPa, 340 MPa, 350 MPa, 360 MPa, 370 MPa, 380 MPa, 390 MPa, 400 MPa, etc., which are not limited here.

[0044] In some embodiments, the sodium-lithium ion exchange depth (DOL-Na) of the chemically strengthened glass is ≥120 μm. DOL-Na refers to the exchange depth of sodium and lithium ions in the compressive stress layer of the chemically strengthened glass. Preferably, DOL-Na is 120 μm to 150 μm, more preferably 120 μm to 140 μm. DOL-Na can be 120 μm, 125 μm, 130 μm, 135 μm, 140 μm, 145 μm, 150 μm, etc., and is not limited thereto.

[0045] In some embodiments, the potassium-sodium ion exchange depth (DOL-K) of the chemically strengthened glass is ≥8.7 μm. DOL-K refers to the potassium ion exchange depth in the compressive stress layer of the chemically strengthened glass. Preferably, DOL-K is 8.7 μm to 15 μm, more preferably 8.7 μm to 13 μm. DOL-K can be 8.7 μm, 9 μm, 9.5 μm, 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm, 15 μm, etc., and is not limited herein.

[0046] In some embodiments, the thickness of the chemically strengthened glass is 0.08mm to 1.5mm, and can be 0.08mm, 0.1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0047] This invention optimizes the composition ratio of the glass composition, enabling the glass system to be mass-produced through various processes such as float glass, overflow glass, rolling glass, and down-drawing glass.

[0048] This invention also provides a method for preparing chemically strengthened glass, referring to... Figure 1 This includes the following steps: S10. Weigh out the glass raw materials according to the composition of the glass composition of the present invention; S20. Melt, clarify, homogenize, shape, and anneal the glass raw materials to obtain a glass substrate; S30: Chemically strengthened glass is obtained by chemically strengthening a glass substrate.

[0049] In some embodiments, the chemical enhancement treatment includes a first enhancement treatment and a second enhancement treatment. The first enhancement treatment primarily promotes the exchange of sodium and lithium ions, while the second enhancement treatment promotes the exchange of potassium and sodium ions.

[0050] In some embodiments, the first strengthening process includes a first molten salt, wherein the glass substrate is immersed in the first molten salt for the first strengthening process, and the first molten salt includes NaNO3.

[0051] In some embodiments, the mass percentage of the first molten salt is 100%, for example, it may be 100% NaNO3.

[0052] In some embodiments, the first strengthening temperature of the first strengthening treatment is 430°C to 480°C, and the first strengthening temperature is 1h to 3h.

[0053] In some embodiments, the second strengthening process includes a second molten salt, wherein the glass substrate that has completed the first strengthening process is immersed in the second molten salt for the second strengthening process, and the second molten salt includes KNO3.

[0054] In some embodiments, the second molten salt has a mass percentage content of 100%, for example, it may be 100% KNO3.

[0055] In some embodiments, the second strengthening temperature of the second strengthening treatment is 400℃~450℃, and the second strengthening time is 1h~3h.

[0056] In some embodiments, after the above chemical strengthening treatment is completed, the following treatment is also performed: S40, the chemically strengthened glass obtained after the chemical strengthening treatment is cleaned and dried.

[0057] In some embodiments, the method for preparing chemically strengthened glass further includes the following steps: S30, chemical strengthening treatment, that is, chemically strengthening the chemically strengthened glass to obtain chemically strengthened glass.

[0058] In some embodiments, the chemical strengthening treatment includes a pretreatment, which includes preheating the glass substrate at a temperature of 380°C to 400°C for a time of 30 min to 60 min.

[0059] In some embodiments, during the forming step, the glass substrate can be formed by any one of the following methods: float glass, overflow glass, calendering glass, and pull glass.

[0060] The chemically strengthened glass prepared by this invention has excellent properties and can be used as a front cover or back cover for touch screens or other electronic smart terminals. It can also be applied to photovoltaic power generation devices, automotive windows, automotive protective glass, and pharmaceutical glass containers or primary packaging.

[0061] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and are not intended to limit the present invention.

[0062] Examples 1 to 10 The preparation method of chemically strengthened glass in this embodiment is as follows: S10. Weigh out the glass raw materials and clarifying agents NaNO3 and SnO2 according to the composition of the glass composition in Table 1. The mass ratio of NaNO3 to SnO2 is 10:1, and the mass of the clarifying agent is 0.2% of the total mass of the glass raw materials. Mix the glass raw materials and clarifying agents evenly to obtain a mixture.

[0063] S20. Pour the mixture into a platinum-rhodium crucible, then heat and melt it at 1610℃~1650℃ for 4 hours and mix it evenly to obtain a glass slurry. Take out the glass slurry from the crucible, pour it into a preheated mold to cast it into a block, and then put it into a muffle furnace at 630℃ for 2 hours for precision annealing. After the muffle furnace cools down to room temperature, take it out to obtain a glass substrate.

[0064] S30. The prepared glass substrate is subjected to chemical strengthening treatment, which includes a first chemical strengthening treatment and a second chemical strengthening treatment.

[0065] During the first chemical strengthening treatment, the glass substrate is immersed in a first molten salt NaNO3 with a mass concentration of 100%, the first strengthening temperature is 430℃~480℃, and the first strengthening time is 1h~3h.

[0066] In the second chemical strengthening process, the glass substrate that has completed the first chemical strengthening process is immersed in a second molten salt KNO3 with a mass concentration of 100%. The second strengthening temperature is 400℃~450℃ and the second strengthening time is 1h~3h, to obtain chemically strengthened glass.

[0067] S40. Clean and dry the chemically strengthened glass.

[0068] Comparative Example 1 Comparative Example 1 prepared chemically strengthened glass according to the preparation method of Example 1. The difference is that the composition of the glass composition in Comparative Example 1 is different, as detailed in Table 1.

[0069] Comparative Example 2 Comparative Example 2 prepared chemically strengthened glass according to the preparation method of Example 1. The difference is that the composition of the glass composition in Comparative Example 1 is different, as detailed in Table 1.

[0070] Performance testing The physical and chemical properties and strengthening properties of the 0.55 mm thick chemically strengthened glass in the examples and comparative examples were tested.

[0071] 1. In this invention, unless otherwise stated, a Japanese Orihara FSM-6000LE+SLP1000 surface stress analyzer was used to test the CS and DOL of the chemically strengthened glasses of each embodiment and comparative example after ion exchange. Using a birefringence imaging system, polarized light of a specific wavelength passes through glass with a stress gradient, generating a refracted optical path difference, and the relevant stress distribution indices are calculated: CS, CS-Na, DOL-Na, and DOL-K.

[0072] Note: CS refers to the compressive stress value on the surface of chemically strengthened glass, which is mainly affected by the replacement of sodium ions in the glass by potassium ions in the molten salt.

[0073] CS-Na refers to the compressive stress value on the surface of chemically strengthened glass, which is mainly affected by the replacement of lithium ions in the glass by sodium ions in the molten salt.

[0074] DOL-Na refers to the exchange depth of sodium and lithium ions in the compressive stress layer of chemically strengthened glass. DOL-K refers to the potassium ion exchange depth in the compressive stress layer of chemically strengthened glass.

[0075] 2. Determine the density of chemically strengthened glass before and after chemical strengthening according to ASTM C-693, in g / cm³. 3 .

[0076] 3. The overall sandpaper drop performance was tested using a mobile phone controlled drop tester. The specific test conditions were: marble platform, 195g total weight, 60cm base height, increasing by 5cm, once per height, until it broke.

[0077] The results of the above tests are shown in Tables 1 and 2.

[0078] Table 1. Glass composition and properties of chemically strengthened glass in Examples 1 to 6

[0079] Table 2. Composition and properties of the glass compositions of Examples 7 to 10, and Comparative Examples 1 and 2.

[0080] As can be seen from the performance test results of the glasses in each embodiment shown in Tables 1 and 2, the chemically strengthened glass prepared according to the glass composition of the embodiment involves two-step strengthening. In the first step, the first molten salt of the chemical strengthening treatment is NaNO3 with a mass concentration of 100%, the first strengthening temperature is 430℃~480℃, and the first strengthening time is 1h~2h. In the second step, the second molten salt of the chemical strengthening treatment is KNO3 with a mass concentration of 100%, the second strengthening temperature is 400℃~430℃, and the second strengthening time is 1h~2h. The chemically strengthened glass obtained after chemical ion strengthening exchange meets the following requirements: CS≥1000MPa, CS-Na≥300MPa, DOL-Na≥120μm, and DOL-K≥8.7μm.

[0081] The glass components of Comparative Example 1 are all within the requirements of this invention, but C=2.47, which does not meet the requirements of this invention. The chemically strengthened glass obtained after chemical strengthening treatment has CS=852.6MPa, CS-Na=261.5MPa, DOL-Na=134.2μm, DOL-K=11μm, and linear stress strength F=1.58. The drop height of the whole machine is 130cm.

[0082] In Comparative Example 2, the K2O component in the chemically strengthened glass is not within the requirements of this invention. Even if A, B, and C are within the requirements of this invention, the chemically strengthened glass obtained has CS=883.8MPa, CS-Na=273.2MPa, DOL-Na=133.7μm, DOL-K=9.3μm, and linear stress intensity F=1.5, and the drop height of the whole machine is 130cm.

[0083] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A glass composition characterized in that, The glass composition comprises the following components in terms of mass percentage: SiO2: 50% to 60%, Al2O3: 20% to 30%, B2O3: 1% to 6%, P2O5: 0.5% to 5%, Li2O: 2% to 6.5%, Na2O: 3% to 7%, K2O: 0.1% to 1%, CaO: 0.1% to 4%, SrO: 0.1% to 4%, satisfying: 1.67≤A=(SiO2+B2O3) / (P2O5+Al2O3)≤2.91, 0.37≤B=(Li2O+K2O) / Na2O≤2.64, 3.03≤C=(Al2O3+P2O5+CaO+SrO) / (Li2O+Na2O+K2O)≤3.

76.

2. The glass composition of claim 1, wherein, The glass composition further comprises an additive in terms of mass percentage: 0 to 1%, the additive comprising at least one of MgO, TiO2, ZnO, Y2O3.

3. A chemically strengthened glass characterized in that, The chemically strengthened glass comprises the glass composition of claim 1 or 2.

4. The chemically strengthened glass according to claim 3, wherein The stress relaxation index F of the chemically strengthened glass is defined as: 1.97≤F=100×(ρafter-ρbefore)×(CS-CS-Na) / (DOL-Na-DOL-K).

5. The chemically strengthened glass according to claim 4, wherein 1.97≤F=100×(ρafter-ρbefore)×(CS-CS-Na) / (DOL-Na-DOL-K)≤4.

43.

6. The chemically strengthened glass according to any one of claims 3 to 5, characterized in that, The chemically strengthened glass satisfies: The surface stress CS of the chemically strengthened glass is≥1000MPa; and / or, The surface stress CS-Na of the chemically strengthened glass after ion exchange of sodium ions and lithium ions is≥300MPa; and / or, The exchange depth DOL-Na of sodium ions and lithium ions of the chemically strengthened glass is≥120μm; and / or, The exchange depth DOL-K of potassium ions and sodium ions of the chemically strengthened glass is≥8.7μm.

7. The chemically strengthened glass according to claim 3, wherein The thickness of the chemically strengthened glass is 0.08mm to 1.5mm.

8. A method of producing a chemically strengthened glass, characterized by, The method comprises the following steps: The glass raw materials are weighed according to the composition of the glass composition of claim 1 or 2; The glass raw materials are melted, refined, homogenized, formed, and annealed to obtain a glass substrate; The glass substrate is subjected to a chemical strengthening treatment to obtain the chemically strengthened glass of any one of claims 3 to 7.

9. The method of claim 8, wherein the chemical strengthening of the glass is performed by immersing the glass in a molten salt bath. The chemical strengthening treatment comprises a first step strengthening treatment and a second step strengthening treatment; The first step strengthening treatment comprises a first molten salt, the first molten salt comprising NaNO3, the first step strengthening treatment having a first strengthening temperature of 430℃ to 480℃, and the first strengthening temperature lasting for 1h to 3h; The second step strengthening treatment comprises a second molten salt, the second molten salt comprising KNO3, the second step strengthening treatment having a second strengthening temperature of 400℃ to 450℃, and the second strengthening temperature lasting for 1h to 3h.

10. An electronic device, comprising: The electronic device comprises the chemically strengthened glass of any one of claims 3 to 7.

Images