Chemically strengthened glass articles

Abstract

The lithium aluminosilicate glass-based article contains 55.0 mol% to 75.0 mol% of SiO2, 1.0 mol% to 18.0 mol% of Al2O3, and 9.0 mol% to 25.0 mol% of Li2O. The glass-based article has a thickness of less than 0.74 mm, and the fracture toughness of the intermediate surface composition of the glass-based article is 0.75 [Math 1] The compression depth is greater than or equal to TIFF2026522856000041.tif5114 and greater than or equal to 0.14t, where t is the thickness of the glass-based article. The glass-based article is designed to have a single induction mode in the prism-coupled spectrum at wavelengths of 360 nm to 405 nm for at least one of transverse magnetic field polarization or transverse electric field polarization.

Description

[Technical Field]

[0001] This application claims priority under Section 119 of the United States Patent Act to U.S. Provisional Application No. 63 / 522,024, filed on June 20, 2023, the contents of which this Provisional Application is relied upon and incorporated in its entirety by reference herein.

[0002] This specification generally relates to lithium aluminosilicate glass and lithium aluminosilicate glass ceramics. More specifically, this specification covers lithium-containing alkali aluminosilicate glass and lithium aluminosilicate glass ceramics having tuned mechanical properties for producing low-cost glass and glass ceramic articles with low thickness, high fracture toughness, and high compression depth. [Background technology]

[0003] For example, there is an ongoing need to provide glass and glass-ceramic articles that possess the mechanical properties required to function as covers for portable electronic devices such as mobile phones, tablets, and smartwatches. Glass and glass-ceramics used for such purposes must have certain mechanical properties, such as strength to withstand cracking and shattering, as well as scratch resistance. These mechanical properties are at least partially related to the stress profile of the glass or glass-ceramic article, including compressive stress and central tension. [Overview of the project]

[0004] This disclosure relates to glass and glass-ceramic compositions having stress profiles that can be easily and rapidly measured for quality control purposes by prism-coupled spectroscopy.

[0005] The first aspect is a lithium aluminosilicate glass-based article, comprising SiO2 of 55.0 mol% or more and 75.0 mol% or less, Al2O3 of 1.0 mol% or more and 18.0 mol% or less, and Li2O of 9.0 mol% or more and 25.0 mol% or less. The glass-based article has a thickness of less than 0.74 mm, and the fracture toughness of the intermediate plane composition of the glass-based article is 0.75

Number

[0006] The second aspect includes the glass-based article of the first aspect, wherein the glass-based article has a thickness of 0.67 mm or less.

[0007] The third aspect includes the glass-based article according to the previous aspect, wherein the glass-based article has a thickness of 0.43 mm or less.

[0008] The fourth aspect includes the glass-based article according to the previous aspect, wherein the glass-based article has a fracture toughness of 0.80

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[0009] The fifth aspect includes the glass-based article according to the previous aspect, wherein the glass-based article has a fracture toughness of 0.85

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[0010] The sixth aspect includes the glass-based article according to the previous aspect, wherein the glass-based article is a glass ceramic.

[0011] The seventh aspect is that the glass-based article is 1.00

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[0012] The eighth aspect is that the glass-based article is 1.10

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[0013] The ninth embodiment includes the glass-based article described in the preceding embodiment, wherein the glass-based article has a surface compressive stress of 150 MPa or more.

[0014] The tenth aspect is a CS in which the glass-based article is (20 + 100 * t) or more. k The glass article according to the prior embodiment comprises the formula, wherein t is the thickness of the glass article measured in mm.

[0015] An eleventh embodiment includes a glass-based article according to the prior art, wherein both the transverse magnetic field (TM) spectrum and the transverse electric field (TE) spectrum have a single fringe corresponding to an induced optical mode at wavelengths of 360 nm to 405 nm.

[0016] A twelfth embodiment includes a glass-based article according to a prior embodiment, wherein the interval between one induction mode and the critical angle is 0.00012 refractive index units (RIU) or more for at least one of the TM polarization and TE polarization.

[0017] A thirteenth embodiment includes a glass-based article according to the prior embodiment, wherein the interval between one induction mode and the critical angle is 0.00012 RIU or greater for both TM polarization and TE polarization.

[0018] A fourteenth embodiment includes a glass-based article according to the prior embodiment, wherein the interval between one induction mode and the critical angle is 0.00020 RIU or more for at least one of the TM polarization and TE polarization.

[0019] A 15th embodiment includes a glass-based article according to the prior embodiment, wherein the interval between one induction mode and the critical angle is 0.00030 RIU or more for at least one of the TM polarization and TE polarization.

[0020] The sixteenth embodiment includes the glass-based article described in the preceding embodiment, wherein the glass-based article has a central tension of 80 MPa or less.

[0021] The 17th embodiment includes the glass-based article described in the preceding embodiment, wherein the glass-based article has a central tension of 70 MPa or less.

[0022] The 18th embodiment includes the glass-based article described in the preceding embodiment, wherein the glass-based article has a central tension of 60 MPa or less.

[0023] The 19th embodiment includes the glass-based article described in the preceding embodiment, wherein the glass-based article has a central tension of 40 MPa or more.

[0024] The 20th embodiment includes the glass-based article described in the prior embodiment, wherein the glass-based article comprises 60.0 mol% or more and 75.0 mol% or less of SiO2, 1.0 mol% or more and 8.0 mol% or less of Al2O3, and 10.0 mol% or more and 25.0 mol% or less of Li2O.

[0025] The 21st embodiment includes the glass-based article described in the prior embodiment, wherein the glass-based article further comprises 0.2 mol% or more and 1.6 mol% or less of Na2O, 0.05 mol% or more and 1.5 mol% or less of K2O, and 0.5 mol% or more and 5.5 mol% or less of ZrO2.

[0026] A 22nd embodiment includes a glass-based article according to a prior embodiment, which is strengthened by an ion exchange process comprising heating an ion exchange solution to a temperature of 450°C or higher and 550°C or lower, wherein the ion exchange solution contains the following molten salts: 12% or more and 30% or less by weight of NaNO3, 0.02% or more and 0.1% or less by weight of LiNO3, and 75% or more and 80% or less by weight of KNO3, and contacting the glass-based article with the ion exchange solution for a period of 7 minutes or more and 210 minutes or less.

[0027] The 23rd embodiment includes the glass-based article described in the prior embodiment, wherein the glass-based article is a two-dimensional glass-based article.

[0028] The 24th embodiment includes a glass-based article of any one of embodiments 1 to 22, wherein the glass-based article is a 2.5-dimensional glass-based article.

[0029] The 25th embodiment includes a glass-based article of any one of embodiments 1 to 22, wherein the glass-based article is a three-dimensional glass-based article.

[0030] The 26th embodiment includes an electronic product (200) comprising a housing (202) having a front (204), a back (206), and a side (208); a display (210); and a cover substrate (212) disposed on the front (204), which is a glass-based article as described in the prior embodiment.

[0031] Additional features and advantages are described in the following detailed description, some of which will be readily apparent to those skilled in the art from that description, or will be recognized by practicing the embodiments described herein, including the following detailed description, claims, and accompanying drawings.

[0032] It should be understood that both the above overview and the following detailed description are intended to illustrate various embodiments and provide an outline or framework for understanding the nature and characteristics of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments and are incorporated herein and constitute part of this specification. The drawings illustrate the various embodiments described herein and, together with their descriptions, help to illustrate the principles and work of the claimed subject matter. [Brief explanation of the drawing]

[0033] [Figure 1] This is a schematic diagram of a glass-based article containing a compressive stress layer on its surface. [Figure 2] This is an exemplary compressive stress profile of a glass-based article according to embodiments disclosed and described herein. [Figure 3A] This is an exemplary prism-coupled spectrum having one fringe, according to embodiments disclosed and described herein. [Figure 3B] This is an exemplary prism-coupled spectrum with multiple fringes. [Figure 4] This is a schematic diagram of an exemplary article incorporating one of the glass articles according to embodiments disclosed and described herein. [Figure 5] This is the prism-coupled spectrum at 365 nm of a 0.6 mm thick glass-based sample that was ion-exchanged at 530°C for 140 minutes in a salt bath containing 20 wt% NaNO3, 0.1 wt% LiNO3, and approximately 79.9 wt% KNO3, with an additive of 1 wt% silicic acid. [Figure 6] This is the prism-coupled spectrum at 365 nm of a 0.6 mm thick glass-based sample that was ion-exchanged at 470°C for 160 minutes in a salt bath containing 40 wt% NaNO3, 0.1 wt% LiNO3, and 59.9 wt% KNO3. [Figure 7] These are RNF stress profiles measured on approximately 0.6 mm thick samples of glass-based articles that underwent ion exchange according to the conditions shown in Figure 5 (dashed line) and Figure 6 (continuous line). [Figure 8] This is the prism-coupled spectrum at 365 nm of a 0.6 mm thick 3D molded glass-based article that was ion-exchanged at 470°C for 160 minutes with 40 wt% NaNO3, 0.1 wt% LiNO3, and 59.9 wt% KNO3. [Figure 9] This is the prism-coupled spectrum at 365 nm of a 0.6 mm thick 2D glass-ceramic article that was ion-exchanged at 500°C for 90 minutes in a bath of 25 wt% NaNO3, 0.05 wt% LiNO3, and 74.95 wt% KNO3. [Figure 10] Figure 7 (dotted-dotted line) and Figure 8 (continuous line) show the compressive stress profiles of ALD glass ceramic articles that were ion-exchanged according to the conditions, compared with the profile of the drop test article prepared according to the conditions in Figure 6. [Figure 11] The peak tension / central tension (PT, CT) of a 0.6 mm thick glass ceramic, with 3D formation heat treatment prior to ion exchange, is expressed as a function of ion exchange time at 500°C. The ion exchange bath contains approximately 20 wt% NaNO3, 79.95 wt% KNO3, and 0.05 wt% LiNO3, and includes a 1 wt% silicate additive. [Figure 12] This is a 365 nm prism-coupled spectrum of a 0.6 mm chemically strengthened glass-ceramic article subjected to 3D heat treatment, illustrating several examples of the desirable 1-fringe spectrum. [Figure 13A] This is the prism-coupled spectrum at 365 nm of a 0.49 mm glass-ceramic article after ceramicizing with ion exchange at 500°C for 100 minutes in 15 wt% NaNO3, 0.033 wt% LiNO3, and the remaining approximately 85 wt% KNO3, without 3D formation heat treatment. [Figure 13B] Figure 13A shows the stress profile of a 0.49 mm sample after removing 2 microns of material per side to improve surface strength. [Figure 14A]Prismatic coupled spectra of 0.4 mm glass-ceramic articles without 3D heat treatment at 500°C in 22 wt% NaNO3, 0.027 wt% LiNO3, and 87.963 wt% KNO3 with a 1 wt% silicate additive, after ion exchange with no removal, removal of 1.6-1.7 microns per side, and removal of 2 microns per side, followed by three ion exchanges (60 min, 75 min, and 90 min). [Figure 14B] This is the stress profile of a 0.42 mm thick glass-ceramic sample with 90 minutes of ion exchange and 2 microns of post-ion-exchanged material removal per side. [Figure 15] This spectrum shows the change in the 1-fringe target spectrum on a 0.6 mm thick glass-ceramic article that was ion-exchanged at 500°C for 130 minutes in a bath of 20 wt% NaNO3, 0.03 wt% LiNO3, and 79.97 wt% KNO3, depending on the LiNO3 content in the bath and the addition of TSP. [Figure 16] This is the 365 nm prism-coupled spectrum of a 0.57 mm thick glass ceramic that was ion-exchanged with 25 wt% NaNO3 and 0.5 wt% LiNO3 at 500°C for 3.5 hours. [Figure 17] Figure 16 shows the RNF stress profile of a 0.57 mm thick glass-ceramic article. [Figure 18] This is the 365 nm FSM spectrum of a 0.5 mm thick 3D molded glass ceramic that was ion-exchanged at 500°C for 2.43 hours with 25 wt% NaNO3 and 0.5 wt% LiNO3. [Figure 19] Figure 18 shows the RNF compressive stress profile of a 0.5 mm thick glass-ceramic article. [Figure 20] In a molten salt bath containing approximately 4.95 wt% NaNO3, 93.56 wt% KNO3, and approximately 1.49 wt% LiNO3, ion exchange was performed at 450°C for 2.5 hours, resulting in 0.89

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[0034] This disclosure pertains to chemically strengthened cover glass for portable electronic devices such as smartphones, tablets, smartwatches, and premium portable laptop computers. 0.8 or 0.85

number

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[0035] The glass articles disclosed and described herein have surface spikes that produce a single fringe in prism-coupled measurements in TM polarization state, TE polarization state, or both. In the case of transparent cover glass products such as cover glass for telephone screens and tablet screens, this is a single fringe when the measurement is obtained at wavelengths of 405 nm or less, preferably 385 nm or less. Low-cost quality control (QC) of lithium aluminosilicate glass and glass ceramics can be utilized by evaluating glass articles for this single fringe using existing prism-coupled stress meters already available in state-of-the-art manufacturing facilities. This QC methodology can replace expensive and time-consuming conventional state-of-the-art techniques used to measure the stress profiles of glass articles, such as integrated stress meters, by utilizing scattered light polarization methods at least in part.

[0036] The advantages of QC are particularly strong for glass-ceramics and glass with relatively low to moderate PT (e.g., less than about 90 MPa), and generally for thinner glass-based articles (e.g., glass-based articles with a thickness of less than 0.74 mm or less than 0.50 mm, as described below). In all of these cases, scattered light polarization results in relatively poor QC performance due to limited PT, relatively small thickness, or particularly high optical (spot) noise, especially in transparent glass-ceramic articles. Glass-based articles formulated to have one fringe surface spike, as disclosed and described herein, offer the advantages of low-cost QC means; a useful CS boost in the first few microns to increase resistance to high stress fracture; no reduction in performance in the deeper parts of the profile due to suboptimal conditions of the deep profile; and no cost increase due to excessive ion exchange time required to reach two fringe spikes. Further advantages include low-cost quality control, and the ability to measure all manufactured parts very quickly using existing evanescent prism-coupled (EPC) stress meters. This QC method is significantly less expensive than using SLP, especially for thin glass and glass ceramics, when brittleness is not an issue (i.e., PT is not too high). One fringe EPC-based QC is equally applicable to low-thickness glass-based articles, such as those less than 0.45 mm, less than 0.42 mm, and even less than 0.35 mm, compared to greater thicknesses. In contrast, the performance of SLP-based QC degrades significantly at lower thicknesses, as the useful signal is proportional to thickness and PT.

[0037] Another advantage of the glass-based articles disclosed and described herein is a higher surface CS compared to articles made from the same base glass or glass ceramic without 1-fringe K surface spikes. Compared to 2-fringe surface spikes mounted on the same glass or glass ceramic, the glass-based articles disclosed and described herein have reduced manufacturing costs, increased PT, or stress integrals in the deeper parts of the stress profile, in addition to knee (knee stress or CS).k ) higher compressive stress, or higher CS k It has either a higher surface area (CS) or a higher surface area (CS).

[0038] As described above, glass articles exhibiting a single fringe in the prism-coupled spectrum have advantageous properties for use as covers on electronic devices, and the QC of such glass articles can be easily performed by observing the single fringe of such glass articles. Therefore, it has been unexpectedly discovered that it is possible to produce such glass compositions ideal for such applications, especially when the thickness of the cover glass is relatively small. Accordingly, glass articles according to the embodiments disclosed and described herein are formulated from glass compositions that can be chemically strengthened to have a stress profile that provides a single fringe when evaluated by prism-coupled spectral analysis.

[0039] Here, lithium aluminosilicate glass compositions according to various embodiments are referred to in detail. The physical properties of lithium aluminosilicate glass articles may generally be related to the glass composition and its strengthening treatment.

[0040] For this purpose, lithium aluminosilicate glass compositions have good ion exchange capacity, and chemical strengthening processes are used to achieve high strength and toughness properties in alkali aluminosilicate glass compositions. Lithium aluminosilicate glass compositions have high ion exchange capacity with good moldability and quality. Substitution of Al2O3 in the silicate glass network increases the interdiffusivity of monovalent cations during ion exchange. The diffusivity, measured by the diffusion coefficient, is one of the important factors determining the ion exchange capacity in lithium aluminosilicate glass compositions, depending on the glass framework and ion size. High strength and high toughness glass articles can be achieved by chemical strengthening in a molten salt bath (e.g., KNO3).

[0041] This specification describes lithium aluminosilicate glass-based compositions that can be ion-exchanged to achieve high CS with good DOL, and according to embodiments, the physical properties of the lithium aluminosilicate glass-based compositions according to embodiments, and the advantages of the ion-exchange capacity of the lithium aluminosilicate glass-based compositions according to embodiments before and after ion exchange.

[0042] In the embodiments of the glass compositions described herein, the concentrations of the constituent components (e.g., SiO2, Al2O3, etc.) are given in mole percent (mol%) on an oxide basis, unless otherwise specified. The constituent components of the lithium aluminosilicate glass compositions according to the embodiments are considered individually below. It should be understood that any of the various enumerated ranges of one constituent component may be combined with any of the various enumerated ranges of any other constituent component.

[0043] In some embodiments, the main glass-forming component is silica (SiO2), which is the largest component of the composition and therefore the main component of the resulting glass network. Although not bound by theory, SiO2 improves the chemical durability of the glass, specifically the resistance of the glass-based composition to decomposition in acids and to decomposition in water. If the SiO2 content is too low, the chemical durability and chemical resistance of the glass are reduced, and the glass may become more susceptible to corrosion. Therefore, in embodiments, a high SiO2 concentration is generally desired. However, if the SiO2 content is too high, the higher the SiO2 concentration, the greater the difficulty of melting the glass, which adversely affects the formability of the glass and thus the formability of the glass may decrease.

[0044] In the embodiments, the glass-based composition generally contains an amount of SiO2 of 55.0% or more and 75.0 mol% or less. In the embodiments, the glass-based composition contains an amount of SiO2 of 62.0 mol% or more or 65.0 mol% or more. In the embodiments, the glass-based composition contains an amount of SiO2 of 72.0 mol% or less or 70.0 mol% or less. In the embodiments, the glass-based composition includes an amount of SiO2 of 62.0 mol% or more and 72.0 mol% or less, for example, 65.0 mol% or more and 70.0 mol% or less, or 67.0 mol% or more and 69.0 mol% or less, as well as all and partial ranges within the disclosed range. In one or more embodiments, the glass-based composition includes an amount of SiO2 of 55.0 mol% or more and 70.0 mol% or less, for example, 60.0 mol% or more and 70.0 mol% or less, or 60.0 mol% or more and 65.0 mol% or less, as well as all and partial ranges within the disclosed range.

[0045] The glass-based composition of the embodiment may further contain Al2O3. Al2O3, like SiO2, can serve as a glass network-forming material. Due to its tetrahedral coordination in the glass melt formed from a properly designed glass-based composition, Al2O3 can increase the viscosity of the glass-based composition, and if the amount of Al2O3 is too high, it can reduce the moldability of the glass-based composition. However, when the concentration of Al2O3 is balanced with respect to the concentration of SiO2 and the concentration of alkali oxides in the glass-based composition, Al2O3 can lower the liquidus temperature of the glass melt, thereby improving the liquidus viscosity and enhancing the compatibility of the glass-based composition with certain forming processes, such as fusion forming processes.

[0046] In embodiments, the glass-based composition generally includes Al2O3 at concentrations of 1.0 mol% to 18.0 mol%, 2.0 mol% to 7.0 mol%, greater than 3.0 mol% to 6.0 mol%, 3.5 mol% to 6.5 mol%, or 3.5 mol% to 6.0 mol%, as well as all and partial ranges within the disclosed range. In one or more embodiments, the glass-based article includes 10.0 mol% to 18.0 mol%, for example, 12.0 mol% to 16.0 mol%, or 14.0 mol% to 16.0 mol%, as well as all and partial ranges within the disclosed range.

[0047] According to the embodiment, the glass-based composition may also contain alkali metal oxides such as Li2O, Na2O, and K2O. A combination of these alkali metal oxides (e.g., Li2O + Na2O + K2O) may also be referred to as R2O. In the embodiment, the amount of R2O is greater than 18.0 mol%, for example, greater than 19.0 mol%, or 20.0 mol% or more. Having a glass-based composition with this amount of alkali metal oxide, particularly Li2O, can result in a deep compression depth (DOC) and surface compressive stress (CS). In addition, alkali metal oxides, particularly Li2O, provide a short ion exchange time with high DOC and high central tension (CT).

[0048] In some embodiments, other alkali metal oxides, such as Rb2O and Cs2O, may also be present in the glass-based composition. These alkali metal oxides can reduce the liquidus temperature, increase the liquidus viscosity, and subsequently preserve the glass-forming molten material from crystallization at high temperatures. However, these alkali metal oxides may also produce undesirable effects, such as increasing density and CTE. Therefore, the glass-based compositions of one or more embodiments do not contain these alkalis.

[0049] In one or more embodiments, the glass-based composition may include lithium oxide (Li2O). Without being bound by theory, adding Li2O to the glass-based composition results in a glass suitable for high-performance ion exchange of lithium ions (Li + ) with respect to larger alkali metal ions such as sodium ions (Na + ). Since Li + is very small (ionic radius is 0.06 nm), Li + in the glass enables very rapid ion exchange in a Na + -containing salt bath, generating compressive stress in a short time, thereby enabling the generation of a deep DOC in a short time. However, if there is too much Li2O in the glass, the glass viscosity may decrease and the glass liquidus temperature may increase, thus reducing the glass liquidus viscosity and making mass production difficult. To achieve a good balance between the stress profile and the manufacturing ability, in embodiments, it is desirable to limit the amount of Li2O present in the glass-based composition.

[0050] In embodiments, the glass-based composition includes Li2O in an amount of 9.0 mol% or more and 25.0 mol% or less, such as 18.5 mol% or more and 24.5 mol% or less, 19.0 mol% or more and 24.0 mol% or less, 19.5 mol% or more and 23.5 mol% or less, or 20.0 mol% or more and 23.0 mol% or less, and includes all ranges and sub-ranges within the disclosed ranges. In one or more embodiments, the glass-based composition includes Li2O in an amount of 9.0 mol% or more and 12.0 mol% or less, such as 9.5 mol% or more and 11.5 mol% or less, or 10.0 mol% or more and 11.0 mol% or less, and includes all ranges and sub-ranges within the disclosed ranges.

[0051] In embodiments, the glass-based composition includes sodium oxide (Na2O). The amount of Na2O in the glass-based composition is also related to the ion exchangeability of the glass made from the glass-based composition. Specifically, the presence of Na2O in the glass-based composition allows Na +By increasing the ion diffusivity, the ion exchange rate during ion exchange strengthening of glass can be increased. Furthermore, Na2O can suppress the crystallization of alumina-containing species such as spodumene, mullite, and corundum, thus reducing the liquidus temperature and increasing the liquidus viscosity. However, increasing the amount of Na2O in the glass composition can reduce the elastic modulus and fracture toughness, and / or decrease the annealing and strain points of the glass, thus increasing the CTE and degrading the mechanical properties of the glass. Therefore, in embodiments, it is desirable to limit the amount of Na2O present in the glass composition.

[0052] In the embodiments, the glass-based composition generally contains an amount of Na2O of 0.2 mol% or more and 1.8 mol% or less. In the embodiments, the glass-based composition includes an amount of Na2O of 0.3 mol% or more and 1.6 mol% or less, for example, 0.4 mol% or more and 1.4 mol%, 0.5 mol% or more and 1.2 mol%, or 0.6 mol% or more and 1.0 mol%, as well as all and partial ranges within the disclosed range.

[0053] The glass-based composition according to the embodiment may further contain potassium oxide (K2O). The amount of K2O present in the glass-based composition is also related to the ion exchange properties of the glass-based composition. Specifically, as the amount of K2O present in the glass-based composition increases, the compressive stress in the glass obtained by ion exchange decreases as a result of the exchange of potassium and sodium ions. Furthermore, potassium oxide, like sodium oxide, can decrease the liquidus temperature and increase the liquidus viscosity, but at the same time, it can decrease the elastic modulus and fracture toughness and increase the CTE. Therefore, it is desirable to limit the amount of K2O present in the glass-based composition.

[0054] In the embodiments, the glass-based composition contains K2O in an amount of 0.05 mol% or more and 1.5 mol% or less. In one or more embodiments, the glass-based composition contains K2O in an amount of 0.1 mol% or more and 1.4 mol% or less, for example, 0.2 mol% or more and 1.3 mol% or less, 0.5 mol% or more and 1.2 mol% or less, 0.7 mol% or more and 1.1 mol% or less, or 0.8 mol% or more and 1.0 mol% or less, as well as all and partial ranges within the disclosed range.

[0055] The glass-based compositions of the embodiments may contain titania (TiO2). Titania can be added to the glass-based compositions of the present disclosure without a significant increase in density to increase the elastic modulus and fracture toughness of the glass. However, titania may slow down the ion exchange process. In addition, small amounts of titania can be added to the glass to prevent darkening of the light due to ultraviolet exposure sometimes used in the glass washing process. However, titania may impart undesirable discoloration to the glass. Therefore, the titania content is limited in the embodiments.

[0056] In embodiments, the glass-based composition contains TiO2 in an amount of 0.0 mol% or more and 1.0 mol% or less. It should be understood that in embodiments, the glass-based composition may contain no TiO2 or substantially no TiO2. In one or more embodiments, the glass-based composition contains TiO2 in an amount of 1.0 mol% or less, for example, 0.5 mol% or less, 0.2 mol% or less, or 0.1 mol% or less, and all and partial ranges within the disclosed range.

[0057] The glass-based compositions of the embodiments may contain zirconia (ZrO2). Zirconia can be added to the glass-based compositions of the present disclosure to increase the elastic modulus, fracture toughness, and low-temperature viscosity. However, it has been empirically found that adding too much ZrO2 can increase the liquidus temperature, and therefore adversely affect the crystallization of refractory minerals such as zirconia (ZrO2) and zircon (ZrSiO4) from the glass-forming molten material at high temperatures. Therefore, the zirconia content is limited in the embodiments.

[0058] In some embodiments, the glass-based composition contains ZrO2 in an amount of 0.5 mol% or more and 5.5 mol% or less. In one or more embodiments, the glass-based composition contains ZrO2 in an amount of 1.0 mol% or more and 5.0 mol% or less, for example, 1.5 mol% or more and 4.5 mol% or less, 2.0 mol% or more and 4.0 mol% or less, or 2.5 mol% or more and 3.5 mol% or less, as well as all and partial ranges within the disclosed range.

[0059] The glass-based compositions of the embodiments may contain tin oxide (SnO2). Tin oxide can be added to the glass-based compositions of the present disclosure at low concentrations as a clarifier. However, it has been empirically found that in some cases, particularly when the Al2O3 content is greater than the total content of the modifier, even the addition of very small amounts of SnO2 may cause precipitation of cassiterite (SnO2) from the molten material at high temperatures. Therefore, the tin oxide content is limited in the embodiments.

[0060] In embodiments, the glass-based composition contains an amount of SnO2 of 0.0 mol% or more and 0.5 mol% or less. It should be understood that in embodiments, the glass-based composition may contain no SnO2 or substantially no SnO2. In one or more embodiments, the glass-based composition contains an amount of SnO2 of 0.5 mol% or less, for example, 0.4 mol% or less, 0.3 mol% or less, 0.2 mol% or less, or 0.1 mol% or less, and all and partial ranges within the disclosed range.

[0061] According to the embodiments, the glass-based composition may contain phosphorus oxide (P2O5). The presence of P2O5 increases the liquidus viscosity of the glass-based composition by suppressing the crystallization of mullite, spodumene, and several other species (e.g., spinel) from the glass-forming molten material. However, the phosphorus oxide content is limited in the embodiments.

[0062] In the embodiments, the amount of P2O5 in the glass-based composition is 0.0 mol% or more and 2.0 mol% or less. In the embodiments, it should be understood that the glass-based composition does not contain P2O5 or substantially contains it. In one or more embodiments, the glass-based composition contains P2O5 in amounts of 0.0 mol% or more and 2.0 mol% or less, for example, 0.1 mol% or more and 1.8 mol% or less, 0.2 mol% or more and 1.5 mol% or less, 0.5 mol% or more and 1.2 mol% or less, 0.5 mol% or more and 1.0 mol% or less, or 0.7 mol% or more and 1.0 mol% or less, and includes all and partial ranges within the disclosed range.

[0063] In embodiments, the glass-based composition may include B2O3 in amounts of 4.0 mol% or more and 8.0 mol% or less, 4.5 mol% or more and 7.5 mol% or less, 5.0 mol% or more and 7.0 mol% or less, or 5.5 mol% or more and 6.5 mol% or less, as well as all and partial ranges within the disclosed range. In one or more embodiments, the glass-based article does not contain B2O3.

[0064] In embodiments, the glass-based composition may contain MgO in an amount of 3.0 mol% or more and 6.0 mol% or less, for example, 3.5 mol% or more and 5.5 mol% or less, or 4.0 mol% or more and 5.0 mol% or less, and may include all and partial ranges within the disclosed range. In one or more embodiments, the glass-based article does not contain MgO.

[0065] In embodiments, the glass-based composition may contain CaO in an amount of 0.2 mol% or more and 1.0 mol% or less, for example, 0.4 mol% or more and 0.8 mol% or less, or 0.40 mol% or more and 0.6 mol% or less, and may include all and partial ranges within the disclosed range. In one or more embodiments, the glass-based article does not contain CaO.

[0066] Without limiting the possible compositions selected from each of the various components described above, in the embodiments, the glass-based composition may include SiO2 in an amount of 60.0 mol% or more and 75.0 mol% or less, Al2O3 in an amount of 1.0 mol% or more and 8.0 mol% or less, Li2O in an amount of 18.0 mol% or more and 25.0 mol% or less, Na2O in an amount of 0.2 mol% or more and 1.6 mol% or less, K2O in an amount of 0.05 mol% or more and 1.5 mol% or less, ZrO2 in an amount of 0.5 mol% or more and 5.5 mol% or less, P2O5 in an amount of 0.0 mol% or more and 2.0 mol% or less, and SnO2 in an amount of 0.0 mol% or more and 0.5 mol% or less, as well as all and partial ranges within the disclosed range.

[0067] Without limiting the possible compositions selected from each of the various components described above, in the embodiments, the glass-based composition may include SiO2 in an amount of 62.0 mol% or more and 72.0 mol% or less, Al2O3 in an amount of 2.0 mol% or more and 6.0 mol% or less, Li2O in an amount of 20.0 mol% or more and 24.0 mol% or less, Na2O in an amount of 0.4 mol% or more and 1.2 mol% or less, K2O in an amount of 0.1 mol% or more and 1.2 mol% or less, ZrO2 in an amount of 1.5 mol% or more and 4.0 mol% or less, P2O5 in an amount of 0.5 mol% or more and 1.5 mol% or less, and SnO2 in an amount of 0.0 mol% or more and 0.5 mol% or less, as well as all and partial ranges within the disclosed range.

[0068] Without limiting the possible compositions selected from each of the various components described above, in the embodiments, the glass-based composition may include SiO2 in an amount of 66.0 mol% or more and 70.0 mol% or less, Al2O3 in an amount of 2.0 mol% or more and 4.0 mol% or less, Li2O in an amount of 21.0 mol% or more and 23.0 mol% or less, Na2O in an amount of 0.5 mol% or more and 1.0 mol% or less, K2O in an amount of 0.5 mol% or more and 1.1 mol% or less, ZrO2 in an amount of 2.0 mol% or more and 3.5 mol% or less, P2O5 in an amount of 0.7 mol% or more and 1.1 mol% or less, and SnO2 in an amount of 0.0 mol% or more and 0.5 mol% or less, as well as all and partial ranges within the disclosed range.

[0069] Without limiting the possible compositions selected from each of the various components described above, in the embodiments, the glass-based composition may include 55.0 mol% to 65.0 mol% of SiO2, 13.0 mol% to 18.0 mol% of Al2O3, 8.0 mol% to 12.0 mol% of Li2O, 1.0 mol% to 2.0 mol% of Na2O, 0.1 mol% to 0.5 mol% of K2O, 4.0 mol% to 8.0 mol% of B2O3, 3.0 mol% to 5.0 mol% of MgO, and 0.1 mol% to 0.6 mol% of CaO, as well as all and partial ranges within the disclosed range.

[0070] Here, we will consider the physical properties of the lithium aluminosilicate glass compositions disclosed and described herein.

[0071] As described above, in the embodiment, the alkali aluminosilicate glass composition can be strengthened by ion exchange or the like to produce damage-resistant glass for applications such as cover glass and digital screens. Referring to Figure 1, the glass has a first region under compressive stress extending from the surface to the depth of the glass layer DOL (e.g., the first and second compression layers 120, 122 in Figure 1), and a second region under tensile stress or central tension CT extending from the depth of the layer to the center or internal region of the glass (e.g., the central region 130 in Figure 1).

[0072] As used herein, “peak compressive stress” refers to the highest compressive stress (CS) value measured within the compressive stress region. CS has its maximum value at the surface of the glass and varies according to a function of distance d from the surface. Referring again to Figure 1, the first segment 120 extends from the first surface 110 to a depth d1, and the second segment 122 extends from the second surface 112 to a depth d2. Together, these segments define the surface compression or surface CS of the glass 100. In embodiments, the surface CS may be 150 MPa or more and 300 MPa or less. In embodiments, the surface CS may be at least 150 MPa, at least 220 MPa, at least 240 MPa, at least 250 MPa, at least 260 MPa, or at least 280 MPa. In the embodiment, the surface pressure CS may be 210 MPa or more and 290 MPa or less, for example, 220 MPa or more and 280 MPa or less, 230 MPa or more and 270 MPa or less, 240 MPa or more and 260 MPa or less, or about 250 MPa.

[0073] In embodiments, the compressive stress profile may have spikes in a region close to the surface of the glass-based article such that the compressive stress decreases in a first gradient from the surface of the glass-based article to a knee where the gradient of compressive stress transitions to a second gradient which is smaller than the first gradient. The transition point from the first gradient to the second gradient is referred to herein as the knee of the compressive stress profile. The knee may be located within 15 nm from the surface of the glass-based article, for example, within 14 nm, within 13 nm, within 12 nm, within 11 nm, within 10 nm, within 9 nm, or within 8 nm from the surface of the glass-based article.

[0074] Compressive stress profile of the knee (CS k The compressive stress in ) is (20 + 100 * t) MPa or greater, where t is the thickness of the glass-based article in millimeters. In one or more embodiments, the CS of the compressive stress profile k This is (25 + 100 * t) MPa or higher, for example, (30 + 100 * t) MPa or higher, (35 + 100 * t) MPa or higher, or (40 + 100 * t) MPa or higher.

[0075] As used herein, "depth of layer" (DOL) refers to the depth within a glass article where the ions of a metal oxide diffuse into the glass article to the point where the ion concentration reaches its minimum value. The depth of layer DOL after ion exchange in a single molten salt for less than two hours.

[0076] According to one or more embodiments, the central tension (CT) or peak tension (PT) of a glass-based article, CT or PT, is 80 MPa or less, 70 MPa or less, 60 MPa or less, 55 MPa or less, 50 MPa or less, or 48 MPa or less. In one or more embodiments, CT or PT is 35 MPa or more, 40 MPa or more, or 44 MPa or more. Therefore, in the embodiments, CT or PT is 35 MPa or more and 80 MPa or less, for example, 40 MPa or more and 70 MPa or less, 45 MPa or more and 65 MPa or less, or 50 MPa or more and 60 MPa or less.

[0077] In one or more embodiments, the compression depth (DOC) is measured per thickness (t) of the glass-based article (DOC / t) and is 0.14t or greater, for example, 0.15t or greater, 0.16t or greater, 0.17t or greater, 0.18t or greater, 0.19t or greater, or 0.20t or greater. In embodiments, DOC / t is 0.14t or greater and 0.22t or less, for example, 0.15t or greater and 0.21t or less, 0.16t or greater and 0.20t or less, or 0.17t or greater and 0.19t or less.

[0078] When moderate peak tension falls significantly below the brittle limit, glassy articles may tend to fracture with only a single crack extension during fracture events caused by the introduction of deep damage. The high fracture toughness of glassy articles disclosed and described herein, high DOC as described in the embodiments of the present invention, and relatively high CS k When combined, this moderate CT characteristic provides a unique combination of a desirable fracture pattern with low probability of fracture and minimal fragmentation, which in most cases allows electronic devices with such fractured coverslips to be used almost as if the coverslip were unbroken. A QC method based on a single fringe spectrum is very suitable for quality control of this type of product.

[0079] In this embodiment, the thickness of the glass-based article is 0.74 mm or less, for example, 0.72 mm or less, 0.70 mm or less, 0.67 mm or less, 0.64 mm or less, 0.62 mm or less, 0.60 mm or less, 0.58 mm or less, 0.56 mm or less, 0.54 mm or less, 0.52 mm or less, 0.50 mm or less, 0.48 mm or less, 0.46 mm or less, or 0.43 mm or less. For each of the above values, the thickness of the glass-based article is 0.35 mm or more.

[0080] According to the embodiment, the glass-based article is 0.75

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[0081] As described above, a compressive stress layer can be formed in a glass-based article by exposing the glass-based composition to an ion-exchange solution. In embodiments, the ion-exchange solution may be a molten nitrate or a molten sulfate. In embodiments, the ion-exchange solution may be molten KNO3, molten NaNO3, molten LiNO3, or a combination thereof. In certain embodiments, the ion-exchange solution may contain 15% to 40% by weight of molten NaNO3, 0.020% to 0.5% by weight of LiNO3, and 59% to 85% by weight of molten KNO3. In one or more embodiments, the ion-exchange solution may contain 12% to 30% by weight of NaNO3, 0.02% to 0.1% by weight of LiNO3, and 75% to 80% by weight of KNO3.

[0082] A glass-based composition can be exposed to an ion exchange solution by immersing a glass article made from the glass-based composition in a bath of the ion exchange solution, spraying the ion exchange solution onto a glass article made from the glass-based composition, or otherwise physically applying the ion exchange solution to a glass article made from the glass-based composition. When the glass-based composition is exposed, according to the embodiment, the temperature of the ion exchange solution may be between 450°C and 550°C, for example, between 470°C and 515°C, or between 475°C and 500°C. In the embodiment, the glass-based composition may be exposed to the ion exchange solution for a period of 7 minutes to 210 minutes, for example, between 45 minutes and 160 minutes, between 60 minutes and 150 minutes, between 80 minutes and 140 minutes, or between 100 minutes and 120 minutes.

[0083] The glass-based articles according to the embodiments disclosed and described herein have a spike region extending to a depth of about 10 μm from the surface of the glass-based article and a compressive stress (CS) at the knee of about 90 MPa. k It may have a compressive stress profile as shown in Figure 2, with DOC being approximately 120 μm and CT or PT being approximately 48 MPa at a depth of approximately 300 μm. Figure 2 is merely an exemplary stress profile for glass-based articles according to embodiments disclosed and described herein, and it should be understood that the values ​​shown may differ for the various embodiments disclosed and described herein.

[0084] The properties of glass-based articles described above are sufficient for glass-based articles that can be used as glass covers for electronic devices. However, conventional quality control measurements to ensure that glass-based articles have the above properties can be expensive and time-consuming. However, it has been found that molding glass-based articles having the above properties enables faster and lower-cost quality control measurements than conventional methods. Therefore, molding glass-based articles to have the glass-based compositions disclosed herein and strengthening the glass-based articles by the ion exchange processes disclosed herein provides glass-based articles that can utilize the quality control measurement techniques described below.

[0085] Figure 3A shows an exemplary prism-coupled spectrum of a glass article according to embodiments disclosed and described herein, illustrating a single induction mode in the prism-coupled spectrum at wavelengths of 360 nm to 405 nm for at least one of transverse magnetic field polarization or transverse electric field polarization, also referred herein as a “one-fringe spectrum,” and showing a glass article having the desired properties disclosed and described herein. In embodiments, the glass article may have a single induction mode in the prism-coupled spectrum at wavelengths of 360 nm to 405 nm for both transverse magnetic field polarization and transverse electric field polarization. In contrast, Figure 3B shows a multi-fringe prism-coupled spectrum, which shows that the glass article does not have the desired properties disclosed and described herein.

[0086] One-fringe spectra offer unique advantages for quality control of transparent glass ceramics, going beyond the selection of nearly optimal ion exchange times for a given thickness. Compared to conventional chemically strengthened glass ceramics that do not exhibit strongly inductive optical modes, one-fringe spectra provide multiple parameters for quality control, enabling the avoidance of the need for direct tension zone measurement due to slower, more expensive, and low thicknesses such as below 60 MPa and / or moderate peak tensions, as well as inappropriate scattered light polarization for glass and glass ceramics. On the other hand, compared to glass ceramic articles ion-exchanged to exhibit two or more fringes per polarization, one-fringe spectra offer a significantly wider measurement window and accurate CS for a wide range of ion exchange conditions. k This enables measurement. This proves essential for the best glass ceramics with significant crystalline content (e.g., higher or significantly higher, as well as glass phase content by volume), because it is extremely difficult to raise the K concentration in these materials enough to allow significant separation of the fringe. CS k The appropriate measurement window size for measurement increases with increasing fringe separation; therefore, in robust glass ceramics with a high proportion of crystalline phase, it is virtually impossible to have an appropriate measurement window. Recognizing this problem, the inventors have found an effective solution by defining a target 1-fringe spectrum and designing a quality control architecture that enables effective quality control of chemical strengthening and the resulting stress profile at low cost and without imposing artificial yield losses (e.g., due to problematicly narrow measurement windows) that do not involve QC measurements.

[0087] In the embodiment, the interval between one induction mode and the critical angle is 0.00012 refractive index units (RIU) or more for at least one of the TM polarization and TE polarization, for example, 0.00020 RIU or more for at least one of the TM polarization and TE polarization, 0.00025 RIU or more for at least one of the TM polarization and TE polarization, 0.00030 RIU or more for at least one of the TM polarization and TE polarization, or 0.00035 RIU or more for at least one of the TM polarization and TE polarization. In one or more embodiments, the interval between one induction mode and the critical angle is 0.00012 RIU or more for both TM polarization and TE polarization, and 0.00020 RIU or more for at least one of TM polarization or TE polarization, for example, 0.00012 RIU or more for both TM polarization and TE polarization, and 0.00025 RIU or more for at least one of TM polarization or TE polarization, or 0.00012 RIU or more for both TM polarization and TE polarization, and 0.00030 RIU or more for at least one of TM polarization or TE polarization.

[0088] Glass articles made from the glass compositions disclosed herein may be incorporated into other articles, such as displays (or display articles) (e.g., consumer electronics including mobile phones, watches, tablets, computers, navigation systems, etc.), building articles, transport articles (e.g., automobiles, trains, aircraft, ships, etc.), electrical appliances, or any article which may benefit from a certain degree of transparency, scratch resistance, abrasion resistance, or a combination thereof.

[0089] An exemplary article incorporating one of the glass-based articles disclosed herein is shown in Figure 4. Specifically, Figure 4 shows a consumer electronic product 200 including a housing 202 having a front 204, a back 206, and a side 208. A display 210, for example, a light-emitting diode (LED) display or an organic light-emitting diode (OLED) display, is at least partially inside the housing 202. A cover substrate 212 may be positioned on or over the front 204 of the housing 202 so that it is placed on the display 210. The cover substrate 212 may include one of the glass-based articles made from a glass-based composition disclosed herein. The cover substrate 212 may help protect the display 210 and other components of the consumer electronic product 200 from damage. In embodiments, the cover substrate 212 may be bonded to the display 210 with an adhesive. In embodiments, the cover substrate 212 may define all or part of the front 204 of the housing 202. In some embodiments, the cover substrate 212 may define all or part of the front surface 204 and the side surface 208 of the housing 202.

[0090] In embodiments, it should be understood that glass articles may be two-dimensional (2D), 2.5-dimensional (2.5D), or three-dimensional (3D) glass articles. As used herein, a 2D glass article is a glass article having a main surface that is essentially flat, meaning that the thickness of the glass article does not vary significantly across the surface of the glass article and the glass article does not have significant curvature. In a 2D glass article, the edges of the glass article are at an angle of about 90° to the main surface of the glass article. In contrast, a 2.5D glass article has reduced thickness and / or slight curvature at one or more edges of the glass article. In a 2.5D glass article, most of the main surface has uniform thickness and no curvature, but at the edges (e.g., within tens of microns from the edge), the thickness of the glass article decreases and / or the glass article has sharp curvature. In embodiments, a 2.5D glass article can be perceived as a glass article having rounded edges. In addition, a 3D glass article has significant variations in thickness and / or curvature along the main surface of the glass article. In embodiments, the curvature may be significant near the edges of the glass article, but is significantly more pronounced than in a 2.5D glass article. In embodiments, a 3D glass article includes a glass article having wrap-around edges, or a glass article used to cover a curved screen. [Examples]

[0091] The embodiments are further clarified by the following examples. It should be understood that these examples are not limiting to the embodiments described above.

[0092] The glass-based compositions listed in Table 1 were subjected to an ion exchange process as disclosed in the examples provided below. [Table 1]

[0093] Figure 5 shows the 365 nm prism-coupled spectrum (FSM) measured on a 0.6 mm thick glass-ceramic sample having the composition shown in Table 1, ion-exchanged at 530°C for 140 minutes in a salt bath containing 20 wt% NaNO3, 0.1 wt% LiNO3, and 79.9 wt% KNO3, with a 1% silica additive. In face-drop tests using 80-grit Rynowet sandpaper as a cover glass for a 200 g test vehicle, the average failure height was 72 cm, with the entire range of the 10 systems tested ranging from 40 cm to 90 cm. This average failure height was approximately 2.5 times that of the test sample equipped with a 0.6 mm thick Gorilla® glass Victus® cover glass and approximately 2.2 times that of the test vehicle equipped with a Gorilla® glass Victus® 2 cover glass.

[0094] Figure 6 shows the prism-coupled spectra at 365 nm for 0.6 mm thick glass-ceramic samples having the compositions disclosed in Table 1, ion-exchanged at 470°C for 160 minutes in a salt bath containing 40 wt% NaNO3, 0.1 wt% LiNO3, and 59.9 wt% KNO3. When used with 200 g drop test samples in the same 80-grit sandpaper drop test, nine devices showed a mean failure height of 96 cm, with results ranging from 40 cm to 170 cm. This mean failure height was approximately 3.3 times that of comparable systems equipped with Gorilla® glass Victus® cover glass and approximately 2.9 times that of systems equipped with Gorilla® glass Victus® 2 glass.

[0095] Figure 7 shows the stress profiles of 0.6 mm glass-ceramic materials with the compositions shown in Table 1, ion-exchanged according to the conditions represented by the prism-coupled spectra in Figures 5 and 6. Due to the limited optical resolution of the RNF (approximately 1.5–2 microns), the CS spikes near the surface are nearly accurate. Surface compressive stress is extrapolated to compensate for the finite resolution, and this extrapolation introduces an uncertainty of approximately 20–50 MPa in the displayed surface CS, underestimating the surface CS in most cases. The profiles inside the glass beyond the surface spikes can be considered substantially accurate, with only slight uncertainty in the closest neighborhood of the knee point (closest to 10 microns) where CS may be slightly underestimated as a result of LOESS smoothing applied to the raw RNF data to reduce noise in the profiles. The continuous profile representing the conditions in Figure 2 shows a high CS of approximately 135 MPa compared to the dashed line profile of 85 MPa corresponding to the ion-exchange conditions represented by the spectra in Figure 5. k It has. The DOC of the profile in the example in Figure 6 is slightly smaller, partly due to the 1% smaller thickness. The profile corresponding to the state in Figure 2 has a higher CS. k It was observed that this correlated with a somewhat higher mean failure height. In the case of a single-step ion exchange process, surface CS and CS k It should be noted that, in general, this decreases with increasing ion exchange rate, and this rate increases regardless of longer ion exchange time, higher ion exchange temperature, or both. Specifically, for the examples in Figures 4, 5, and 6, the 140-minute exchange at 530°C in the example of Figure 5 is equivalent to approximately three times the ion exchange time under the conditions of Figure 6 (the time is 160 minutes, but the temperature is substantially lower at 470°C).

[0096] Examples illustrated in Figures 4, 5, and 6, particularly the example in Figure 2, demonstrate a very significant increase in drop fracture resistance compared to state-of-the-art chemically strengthened glass, approaching the performance of the best glass-ceramics. On the other hand, state-of-the-art lithium-containing glass-ceramics have much higher central tensions (100-160 MPa), and require quality control through an integrated stress meter such as the ISM-100, which measures surface stress and directly measures the tension zone, in order to ensure that the profile has appropriate DOC and CT, and at the same time, that the CT is within specifications and the glass-ceramics are non-brittle. The substantially low CT for glass-based articles disclosed and described herein is far below the brittleness limit and therefore does not require brittleness control. In addition, at small thicknesses of less than 0.7 mm, direct measurement of the CT of glass-ceramics by scattered light polarization with an accuracy of more than 2 MPa is difficult, and the uncertainty of the measurement is not many times smaller than the specification range, so there are challenges in quality control of products with a lower limit of 44 MPa and an upper limit of 53 MPa. This differs from high-CT glass ceramics, which have a much wider absolute size of the CT specification range window. The high fracture resistance of the examples in Figures 5 and 6, characterized by high fracture toughness and moderate residual stress forming chemical strengthening, offers an opportunity to bring high-performance products to market at a reduced cost, which is a result of a combination of faster ion exchange, less contamination control of the ion exchange bath, and simplified quality control without the need to purchase state-of-the-art integrated stress meters. The example in Figure 1 utilizes FSM-only measurements for quality control (QC). These are fast measurements, typically 2 seconds per measurement, and are generally faster than measurements using integrated stress meters. Compared to state-of-the-art glass ceramics, 140 minutes of ion exchange at 530°C represents a reduction in ion exchange time by about twofold. Bath contamination per run is also reduced by a factor greater than 1.5. Quality control in this example is achieved by FSM spectra, each featuring two fringes in the transverse magnetic field (upper half of the image) spectrum and transverse electric field (lower half of the image) spectrum, as well as knee stress CS. kIt relies on clearly separated critical angle transitions that enable direct measurement. Quality control ensures that the surface spikes have the two fringes required for each polarization, and CS k By observing that the value is positive, we establish that ion exchange occurred to both K and Na ions in the glass. The fringe pattern is determined by the surface CS and the depth of the spikes (DOL). sp ) enables the calculation of DOL sp If it is within the specified range, it is proven that the diffusion amount was appropriate. Then, surface CS and CS k If these are within their specified ranges, this ensures that the total amount of stress in the profile is on target, and considering the amount of diffusion, it verifies that CT is on target and DOC is also on target. This quality control method is well understood and works very well when the target stress profile is not too close to the brittle limit. One limitation in Example 1 was that the length of ion exchange diffusion had to be significantly extended to reach the 2-fringe requirement for quality control. Specifically, when exchanged in a bath with a composition of 20 wt% NaNO3 / 0.1 wt% LiNO3 / 79.9 wt% KNO3, a diffusion time of 140 minutes at 530°C was more than twice the time required to reach the maximum CT of ALD-GC. Thus, CS in the profile kFurthermore, the total stress was unnecessarily reduced due to the excessively long ion exchange. While DOC does not suffer from extending ion exchange beyond the maximum CT point, CSK and surface CS decrease, as does the integral of the compressive stress from the surface to DOC. In addition, each ion exchange run produces about 40-50% more LiNO3 than runs limited to about the maximum CT point, which requires more frequent addition of lithium-capturing compounds such as trisodium phosphate (TSP), which results in more frequent downtime of the ion exchange equipment and more frequent need to empty the bath to wash away accumulated sludge containing phosphoric acid and silicic acid. Moreover, the required temperature of 530°C (to accelerate K diffusion) is only possible with special types of ion exchange equipment that are more corrosion-resistant and generally designed for high-temperature operation. Furthermore, the salt decomposition rate increases dramatically at temperatures above 470°C, requiring more frequent addition of silicic acid to compensate for the pH drift caused by decomposition (the higher the temperature, the more frequently bath treatment is required). Finally, at higher temperatures, the effectiveness of TSP in removing Li from the liquid phase of the molten salt decreases, requiring more TSP to remove units of Li contamination, which leads to faster sludge accumulation requiring more frequent shutdowns to pre-form salt tank cleaning. Such shutdowns are relatively expensive, as they extend equipment downtime by several days, and require dissolving new salt, which also incurs considerable energy and CO2 emissions. While the example in Figure 1 is superior to state-of-the-art glass ceramics in terms of bath contamination, energy use, and ion exchange time, the example in Figure 2 is significantly superior.

[0097] Unlike the example in Figure 5, the example in Figure 6 does not exceed the maximum CT point. This not only results in cost savings, but also higher CS. kThis provides some superior fracture resistance. The example in Figure 6 has one fringe in each of the upper and lower spectra, and only in the upper (TM) spectrum is there a fringe that is well separated from the nearby critical angle transition. The inventors have found this exemplary spectrum suitable for approximate quality control as follows: The interval between the upper fringe and its transition, along with the interval between the upper and lower fringes, can be measured and is required to be within a specific range. As long as both intervals are within the range, if the ion exchange bath had approximately the correct ratio of NaNO3 to KNO3, the glass will have surface CS and CS k It was established that the parameters were within approximately the desired range, and the separation of the upper fringe from the transition confirmed that the diffusion length was nearly correct, and therefore, the DOC and CT were within the desired range. This type of QC is not extremely precise, but is still low-cost and fast based on existing equipment and existing image processing, requiring only the implementation and utilization of a new QC algorithm based on a new interpretation procedure. Due to the small gap between the upper fringe and the transition, the process window may be somewhat limited (for example, a moderate downward deviation in KNO3 concentration and / or temperature may result in a product that cannot be measured and passed), but with reasonably strict control of temperature and salt ratio KNO3:NaNO3, it is possible to produce a product with an FSM spectrum similar to Example 2 and control the quality.

[0098] Figure 8 shows the prism-coupled spectra at 365 nm of a 0.6 mm thick 3D molded glass article having the compositions shown in Table 1, which were ion-exchanged at 470°C for 160 minutes with 40 wt% NaNO3, 0.1 wt% LiNO3, and 59.9 wt% KNO3. This is another example of a spectrum that allows for approximate quality control using the interval between the upper and lower fringes, and the interval between the upper fringe and its transition. In this example, as in the example in Figure 6, the ion exchange is within the optimal range for the diffusion length, in that the ion exchange time is close to the time of maximum CT.

[0099] Figure 9 shows the prism-coupled spectrum at 365 nm of a 0.6 mm thick 2D glass-based article having the composition disclosed in Table 1, ion-exchanged at 500°C for 90 minutes in a bath of 25 wt% NaNO3, 0.05 wt% LiNO3, and 74.95 wt% KNO3. This illustrates an embodiment in which the bath composition and temperature are selected to be in favorable conditions, at the optimal time for maximizing the product CT*TA (where TA is the depth integral of the tensile stress in the tensile region, e.g., the tensile stress within the sheet), having one upper fringe and one lower fringe, each significantly separated from the transition, allowing for the measurement of several parameters with high relative accuracy. These parameters include the gap between the upper and lower fringes, CS k This includes the interval between the upper and lower transitions for direct measurement, as well as the interval between the upper fringe and its transition and the lower fringe and its transition. High relative accuracy means that for each such parameter, the uncertainty of the measurement is significantly smaller than the nominal target value of the parameter. For example, the uncertainty of the interval between the fringe and its transition needs to be significantly smaller than the interval itself to enable precise measurement for quality control purposes. Figure 9 also shows that the leak mode is formed in the upper (TM) spectrum, and any increase in ion exchange time causes a shift in the apparent position of the transition at 365 nm driven by the leak mode, and CS k The edge of a preferred 1-fringe measurement window illustrates this in that it leads to an overestimation of the value. Therefore, in this particular example, it would be better to select a slightly longer wavelength, such as 385 nm or 405 nm, to eliminate proximity of the leak mode to the critical angle and avoid systematic errors associated with the leak mode.

[0100] Figure 10 compares the compressive stress profiles of ceramic glass sheet articles with compositions from Table 1, ion-exchanged according to the conditions in Figure 8 (dotted line) and Figure 9 (continuous line), with the profiles of drop-tested articles prepared according to the conditions in Figure 6. This was done using different baths, temperatures, and ion exchange times to determine the surface spike depth DOL spThis demonstrates that it is possible to obtain substantially identical profiles at depths exceeding [a certain value]. The conditions related to Figure 5 allow for control over more parameters with greater precision, and most importantly, CS k This allows for direct measurement, making it ideal for precise quality control. The ability to measure and control not just two, but four substantially independent parameters enables rigorous, rather than approximate, quality control. Furthermore, it allows for early detection of drifts such as bath composition and temperature.

[0101] Figure 11 shows the central tension of a 0.6 mm glass-ceramic sheet having the composition disclosed and described herein, which underwent a 3D forming thermal cycle according to a normal ceramicing process. The maximum value of the peak tension PT (or central tension CT if the stress profile is symmetric) occurs over an ion exchange time of approximately 92 minutes at 500°C. The ion exchange salt contained approximately 20 wt% NaNO3, 0.05 wt% LiNO3, and 79.95 wt% KNO3, with 1 wt% silicic acid added. LiNO3 was added intentionally to help prevent devitrification of the ceramic phase near the surface during ion exchange. Typically, the stress profile includes the maximum stress integral at a time slightly shorter than the maximum CT time, and the compression depth is substantially stabilized near its maximum value by the maximum CT time. If ion exchange is significantly exceeded beyond the maximum CT time, it usually leads to a reduction in the stress integral, which impairs fracture resistance, as well as increased costs due to reduced utilization of ion exchange equipment and personnel, increased bath contamination, and increased energy consumption. In most cases, it would be preferable to use an ion exchange time of 50% to 130% of the maximum CT time, more preferably about 60% to 120% of the maximum CT time, and ideally 70% to 105% of the maximum CT time. In some cases (such as thicker glass for watch covers, for example in a 1.1mm watch), the preferred stress profile does not have maximum CT or maximum DOC, but rather appropriate DOC, appropriate surface CS, and appropriate spike depth DOL. K , and appropriate knee stress CS KThis is because a DOC of 1.1 mm is rarely required, and is substantially smaller than the maximum DOC obtainable with standard ion exchange techniques for Li-based glass, as a DOC of approximately 160 μm is rarely necessary. One of the objectives of quality control measurements of ion exchange components is to establish that the characteristics of the sample are consistent with chemical enhancements within a target range of conditions, which is usually a preferred range for maximum performance at the minimum associated cost.

[0102] For phone covers of 0.4-0.7 mm, it is generally preferable to operate near the maximum CT point. For watch cover glass, it may be preferable for the stress profile to operate near a point having a surface spike with a depth of 5-8 μm, a DOC exceeding 160 μm but not exceeding 180 μm, and a CSK of at least 150 MPa. For glass ceramics with the compositions of Table 1, and at least some more transparent glass ceramics, it is possible to meet these preferred requirements and implement effective quality control when the article is designed to feature a 1-fringed potassium-based surface spike when measured on a prism coupling instrument at 365 nm (or more generally, 405 nm or less, preferably 385 nm or 375 nm or less). The time to maximum CT depends on the thermal history of the glass or glass ceramic. For ALD glass ceramics, the time to maximum CT at 0.6 mm without post-ceramic 3D forming heat treatment is about 130-135 minutes, which is about 45% longer than the maximum CT time for 3D formed ALD glass ceramics. In the case of 3D formation of fused glass, it should be noted that the cooling time after 3D formation is slower compared to the cooling during the fusion drawing process, and therefore the time to reach maximum CT (cooling temperature) is usually longer for 3D-formed glass.

[0103] The properties of an article that enable effective quality control are not inherent. Rather, for the most accurate control, it is preferable that one fringe corresponding to the induction optical mode be appropriately isolated from the critical angle transition so as to allow for precise determination of the critical angle, the fringe position, and the distance between the fringe and the critical angle. This is because the distance is a quality control variable, and the relative precision of the measurement of that variable must be fine enough to allow normal process variations to be tracked, and the quality control measurement window must be wide enough to allow normal manufacturing without unnecessary yield loss due to out-of-specification results of false positives.

[0104] Furthermore, it should be understood that the time to maximum CT scales as the square of the sample thickness. Therefore, for a typical roller-formed glass article having the compositions disclosed in Table 1, the time to maximum CT is approximately 1 hour for 0.4 mm, approximately 94 minutes for 0.5 mm, and approximately 135 minutes for 0.6 mm. However, for specific 3D forming thermal cycles used in some embodiments of this disclosure, the maximum CT time is approximately 92 minutes for 0.6 mm, approximately 41 minutes for 0.4 mm, and approximately 64 minutes for 0.5 mm.

[0105] Figure 12 shows the prism-coupled spectra obtained at 365 nm for 0.6 mm glass articles having the compositions in Table 1, ion-exchanged at 500°C in three different nitrate-salt mixed baths with different ratios of NaNO3 to KNO3. The NaNO3 content of the baths is 20% by weight, 25% by weight, and 30% by weight, respectively. The baths also contain 0.05% by weight of LiNO3, with the remaining salt being KNO3. The first row of the image corresponds to ion exchange for 70 minutes in a bath containing 20% ​​by weight of NaNO3. The second row of the image corresponds to ion exchange for 90 minutes in a bath containing 25% by weight of NaNO3. The third and fourth rows correspond to ion exchange for 90 minutes and 100 minutes in baths containing 30% by weight of NaNO3, respectively. In each row, the first image represents the ion-exchanged article without removing the material from the surface. The second image in each row corresponds to the removal of approximately 1.5 microns of target material per surface by polishing or etching. In practice, material removal was performed by etching, sometimes exceeding 1.5 microns and approaching 1.6 microns. The third image in each row corresponds to the removal of approximately 2 microns of target material per surface. Fine polishing after ion exchange is often an integral part of finishing chemically strengthened glass articles, as it is effective in removing small scratches and shallow defects that would cause problems with either the appearance or surface strength of the glass article. The prism-coupled spectra in Figure 12, combined with the ion exchange conditions, show the required levels of surface CS and knee stress CS. k Several examples illustrate how quality control can be performed on products having the following characteristics before and after polishing. Specifically, the final spectrum after polishing preferably has a single fringe in each polarization state (the upper part of the image shows the transverse magnetic field or TM polarization state, and the lower part shows the transverse electric field or TE). The normal knee stress is measured by dividing the critical angle birefringence by the stress optical coefficient (SOC), and the critical angle effective index corresponds to the position of the maximum slope on the transition between total internal reflection and partial reflection to the right of the single fringe in the exemplary image. Furthermore, in these examples, the surface compressive stress CS is also measured. surfThis is generally larger than the quality control parameter CS1 introduced here, which is the ratio of the birefringence of the first fringe (the only fringe in the case of a single fringe spectrum) to SOC:

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[0106] Quality control based on prism-coupled measurements can be implemented both before and after polishing. Before polishing, two fringes may be present in at least one polarization, allowing for the measurement of the depth of the K spike and the index increment due to the K ion in that one polarization. If two fringes are also present in other polarization states, the surface CS can be calculated using formulas known in the art, which are commercially available in various quality control software suites.

[0107] The general trend in Figure 12 is that when more significant polishing is required, longer ion exchange times are needed, or the bath needs to have a lower NaNO3 to KNO3 ratio to allow for faster formation of 2-fringe spectra to enable extra K-DOL for polishing. For example, a bath with 20 wt% NaNO3 can accommodate 2 micron polishing after only 70 minutes of ion exchange. Since 70 minutes is significantly shorter than the time for maximum CT at a thickness of 0.6 mm, samples exchanged for longer periods will have higher CTs in baths with higher levels of NaNO3. All three baths can provide excellent stress profiles that allow quality control using prism-coupled measurements after polishing, with high-Na baths (25-30 wt% NaNO3) being more suitable when the required polishing is on the lower side (e.g., 1.5-2 microns), and low-Na baths (20-25 wt% NaNO3) being more suitable when the required polishing is greater than 2 microns.

[0108] The glass-ceramic samples, which have the composition shown in Table 1 and whose material is ceramicized but has not undergone 3D formation treatment, were ion-exchanged at 500°C for 100 minutes in a bath mixture containing approximately 15 wt% NaNO3 and 85 wt% KNO3 by weight, and also contained approximately 0.033 wt% LiNO3 to prevent the formation of a low-index layer due to devitrification of nanocrystals. The prism-coupled spectrum at 365 nm is shown in Figure 13A, characterized by two fringes for each polarization state of the spectrum before polishing, and one fringe spectrum after material removal at 1.33 microns (intermediate image) and 1.94 μm. CS from image k The measured values ​​include 135 MPa after 1.33 μm removal and 125 MPa after 1.94 μm removal. CS k The prism-coupled measurement may have an uncertainty of up to 10 MPa. After removing 1.33-2 microns of material from each side of the glass-ceramic sheet, the spectrum becomes one fringe, and the quality control parameter used is CS. k These are CS1 and the distance between each fringe and its corresponding critical angle transition. The stress profile after polishing is shown in Figure 13B, which was obtained by the RNF technique. The stress profile is characterized by a stress region of 89 microns DOC, approximately 18% of a thickness of 0.49 mm, a peak tension PT of approximately 41.5 MPa, and a tension zone (e.g., tension region TA) of approximately 8.65 MPa* mm, which represents approximately 17.6 MPa when normalized to the sample thickness. The knee stress is approximately 120 MPa depending on the profile.

[0109] Figures 14A and 14B present another embodiment. Figure 14A shows the prism-coupled spectrum at 365 nm for a glass-ceramic sample having the composition disclosed in Table 1 and a thickness of approximately 0.4 mm, ion-exchanged at 500°C in a bath having approximately 12 wt% NaNO3 and approximately 88 wt% KNO3, and also having a small amount of approximately 0.027 wt% LiNO3 to help prevent the formation of a low-index surface layer. The first, second, and third rows represent ion-exchange times of 60 minutes, 75 minutes, and 90 minutes, respectively. The first, second, and third rows of the image represent the cases of no material removal, 1.6 micron target removal per side, and 2 micron target removal per side. Also, CS for 1 fringe spectrum. k The CS1 value is also included. The images clearly show that a 60-minute ion exchange, which applies removal of approximately 1 micron per side, works well, and a 75-minute ion exchange works well for removal targets of about 1.6 μm, but is insufficient for 2-micron removal due to the lack of room for variation in ion exchange and removal around the target. A 90-minute ion exchange works well for removal of 1.7 and 2 microns per side and can comfortably handle removal of 2.1 microns.

[0110] Figure 13B shows the RNF stress profile for a sample thickness of approximately 0.42 mm, with 90 minutes of ion exchange and 2 microns of removal per side. The profile features a central tension of approximately 43 MPa, a DOC of 79 microns, or approximately 18.8% of the thickness, and a tension area of ​​approximately 7.88 MPa* mm, which, when normalized to the sample thickness, represents approximately 18.7 MPa.

[0111] Figure 15 shows an example of how the target spectrum of one fringe changes in response to changes in the ion exchange bath when the ion exchange time and temperature remain constant. The five images show the case of five different ion exchanges performed in the same bath. The second image corresponds to the first ion exchange, where a bath with approximately 20 wt% NaNO3 and 80 wt% KNO3 was modified by adding only 0.02 wt% LiNO3 to prevent the formation of a low index layer. This image represents a high CS version of a fresh bath of the product of the present invention. The bath contained 200 g of salt, and four pieces of glass ceramic with dimensions of 25 mm × 25 mm × 0.6 mm were immersed in each ion exchange run. This is 0.01316

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[0112] Figure 16 shows the FSM spectrum at 365 nm, and Figure 17 shows the RNF stress profile of a 0.57 mm thick glass-ceramic article having the composition shown in Table 1, partly designed to allow for the formation of deeper K spikes, helping to enable already established FSM-based efficient and low-cost quality control. The composition of this glass-ceramic was tuned to allow for a suitable K diffusivity to form at least two fringe spikes in both polarizations by the time ion exchange approaches the maximum central tension. Furthermore, this glass-ceramic achieves higher CT and higher compressive stress than ALD, allowing for greater flexibility in stress profile design. At the same time, the higher CT level is still well below the brittleness limit, allowing the stress profile to be designed to be very far from the limit where FSM-based quality control would be perfectly adequate without any brittleness risk for thicknesses less than approximately 0.74 mm. This composition enables similar profiles to those of ALD, as well as higher CT and higher DOC profiles, allowing for a wider range of application targets. Partly, a higher fringe count is also obtained because the time required for maximum CT is longer (4-5 hours at 500°C for 0.6 mm at 500°C, compared to only about 2.25 hours for 0.6 mm ALD at 500°C). The exemplary profile in Figure 17 shows a CT of about 65 MPa and a slightly higher DOC / t ratio compared to the ALD example.

[0113] Figure 18 shows the 365 nm FSM spectrum of a 0.5 mm glass-ceramic sample having the composition shown in Table 1, which was 3D molded and then ion-exchanged at 500°C for 2.43 hours in a 25 wt% NaNO3 / 0.5 wt% LiNO3 / 74.5 wt% KNO3 bath. Figure 19 shows its RNF compressive stress profile. The profile shows a central tension of approximately 65.2 MPa and a CS of approximately 105 MPa. k It is characterized by spikes with a 15 μm DOL and a surface CS of approximately 250 MPa. The ion exchange time of 2.43 hours is well compared to the time to maximum CT, which is estimated to be about 3 hours for 0.5 mm thick 3D molded material.

[0114] RNF profiling of stress in transparent glass ceramics offers high resolution (approximately 2 microns) for stress profile measurements, but has certain limitations. One limitation is that surface CS has significant uncertainty because it is obtained by extrapolating the RNF signal, which results in buried peak CS artifacts due to finite resolution at the surface and discontinuities in the stress profile. There is some uncertainty about the precise location of the surface, which translates into CS uncertainty in the extrapolation of the profile to replace the buried peak artifacts. Therefore, surface spikes in the RNF profile are shown only as qualitative indicators of the profile shape and not as accurate representations of the actual spikes. Another limitation of RNF profiles is the relatively high noise when profiling transparent glass ceramics. To reduce noise, post-processing is used that utilizes smoothing by the LOESS algorithm, and surface spikes are excluded from the signal provided for smoothing. Thus, the smoothing procedure applies a local linear fit over the deeper extension region of the bottom of the surface spikes, so the CS value at the bottom of the spikes is somewhat reduced by the smoothing procedure, thus the apparent CS k This results in a reduction of CS in the smoothed RNF profile. k Typically, CS is obtained from prism-coupled measurements of a proper spectrum with TM critical angle transitions and TE critical angle transitions. k This will be 10-25 MPa lower. For profiles with spike depths exceeding approximately 10 microns or more, the CS should not be expected to be substantially altered by smoothing, apart from noise reduction.

[0115] Another aspect of the RNF profile is that the raw profile is slightly asymmetric due to the design and operating principle of the asymmetric RNF device. In this disclosure, the RNF profile was symmetrized by removing the antisymmetric components of the profile. This procedure is found to significantly reduce the strain of the RNF profile compared to the actual stress profile.

[0116] The surface CS of the one-fringe glass-ceramic articles listed in Table 1 is typically in the range of 330–390 MPa before polishing after ion exchange, for LiNO3 content, and is reduced by 20–40 MPa per micron of polishing per side, depending on the slope of the K spike. Surface CS was calculated by extending ion exchange until a proper two-fringe spectrum was obtained, which allows for the calculation of surface CS by the assumption of a linear spike. The extended time to the two-fringe spectrum reduces surface CS and CSk compared to the initial values ​​of the ion exchange process. This reduction can be accurately explained by correcting for glass expansion between the one-fringe and two-fringe conditions, noting that expansion is proportional to the square root of the ion exchange time. The surface CS of the two-fringe spectrum was in the range of 310–350 MPa in the two cases studied, and the expansion correction resulted in a surface CS exceeding 350 MPa in the one-fringe case. In some cases, when the bath has a lower Na content, such as 10-15 wt% NaNO3, the surface CS in the 1-fringe spectrum can reach 390 MPa and even higher. When designed for polishing after ion exchange, the ion exchange time is often the same as or longer than the time to the maximum CT, and the surface CS is generally in the vicinity of 350 MPa or less before polishing. After polishing 1.5-2 microns per side, the surface CS can drop to the range of 270-310 MPa. If the ion exchange bath allows some LiNO3 to accumulate without TSP fixation, the surface CS will drop accordingly, but generally above 150 MPa for a preferred manufacturing target profile.

[0117] Fracture toughness (0.89

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[0118] The ion exchange conditions were selected so that the ion exchange time was shorter than the time it took for the central tension to reach its maximum at a thickness of 0.412 mm. This allows for relatively high compressive stress without excessive ion exchange growth. The weight change of the sample after ion exchange was +0.65%. This level of weight increase typically results in linear growth in the vicinity of only 0.1%, which is perfectly manageable for tablet, laptop, and large smartphone applications. In comparison, many modern smartphone cover glasses have ion exchange growth exceeding 0.15%, sometimes exceeding 0.18%, with associated weight increases of 0.9%, 1.2%, and even higher. Such ion exchange conditions pose a challenge for large devices such as tablets and laptops.

[0119] The composition and mechanical properties of the lithium aluminosilicate glass in this example are shown in Table 2 below. [Table 2]

Claims

1. Lithium aluminosilicate glass-based articles, SiO2 between 55.0 mol% and 75.0 mol% ２ and, Al content: 1.0 mol% or more and 18.0 mol% or less ２ O ３ and, Li 9.0 mol% or more and 25.0 mol% or less ２ O and, including, The glass-based article has a thickness of less than 0.74 mm. The fracture toughness of the intermediate surface composition of the glass-based article is 0.75 [Math 1] That's all. The compression depth is 0.14t or more, where t is the thickness of the glass-based article. A lithium aluminosilicate glass article, wherein the glass article is designed to have a single induction mode in a prism-coupled spectrum at a wavelength of 360 nm to 405 nm for at least one of transverse magnetic field polarization or transverse electric field polarization.

2. The glass-based article according to claim 1, wherein the glass-based article has a thickness of 0.67 mm or less.

3. The glass-based article is 0.80 [Math 2] A glass-based article according to any one of the prior claims, having fracture toughness as described above.

4. The glass-based article according to any one of the prior claims, wherein the glass-based article is a glass ceramic.

5. The glass-based article according to any one of the prior claims, wherein the glass-based article has a surface compressive stress of 150 MPa or more.

6. The glass-based article is (20 + 100 * t) or more CS ｋ A glass-based article according to any one of the prior claims, wherein t is the thickness of the glass-based article measured in mm.

7. A glass-based article according to any one of the prior claims, wherein both the transverse magnetic field (TM) spectrum and the transverse electric field (TE) spectrum have a single fringe corresponding to an induced optical mode at wavelengths of 360 nm to 405 nm.

8. A glass-based article according to any one of the prior claims, wherein the interval between one induction mode and the critical angle is 0.00012 refractive index units (RIU) or more for at least one of the TM polarization and TE polarization.

9. A glass-based article according to any one of the prior claims, wherein the interval between one induction mode and the critical angle is 0.00012RIU or more for both TM polarization and TE polarization.

10. The glass-based article according to any one of the prior claims, wherein the interval between the one induction mode and the critical angle is 0.00020 RIU or more for at least one of the TM polarization and TE polarization.

11. The glass-based article according to any one of the prior claims, wherein the interval between the one induction mode and the critical angle is 0.00030 RIU or more for at least one of the TM polarization and TE polarization.

12. The glass-based article according to any one of the prior claims, wherein the glass-based article has a central tension of 80 MPa or less.

13. The glass-based article according to any one of the prior claims, wherein the glass-based article has a central tension of 40 MPa or more.

14. The glass-based article is SiO2 60.0 mol% or more and 75.0 mol% or less ２ and, Al content of 1.0 mol% or more and 8.0 mol% or less ２ O ３ and, Li of 10.0 mol% or more and 25.0 mol% or less ２ The glass article according to any one of the preceding claims, comprising

15. The glass-based article is Na: 0.2 mol% or more and 1.6 mol% or less ２ O and, K 0.05 mol% or more and 1.5 mol% or less ２ O and, ZrO 0.5 mol% or more and 5.5 mol% or less ２ A glass-based article according to any one of the prior claims, further comprising the above.

16. The glass-based article is The ion exchange solution is heated to a temperature of 450°C or higher and 550°C or lower, wherein the ion exchange solution contains the following molten salts: NaNO12% or more by weight and 30% or less by weight ３ , LiNOx content of 0.02% by weight or more and 0.1% by weight or less ３ , and KNO 75% or more by weight and 80% or less by weight ３ , including heating, A glass-based article according to any one of the prior claims, which is strengthened by an ion exchange process, comprising contacting the glass-based article with the ion exchange solution for a period of 7 minutes or more and 210 minutes or less.

17. The glass-based article according to any one of the prior claims, wherein the glass-based article is a two-dimensional glass-based article.

18. The glass-based article according to any one of claims 1 to 16, wherein the glass-based article is a 2.5-dimensional glass-based article.

19. The glass-based article according to any one of claims 1 to 16, wherein the glass-based article is a three-dimensional glass-based article.

20. An electronic product (200), A housing (202) having a front (204), a rear (206), and a side (208), Display (210) and, An electronic product (200) comprising: a cover substrate (212) disposed on the front surface (204), which is a glass-based article as described in any one of the prior claims.

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