Precursor Glasses and Transparent Glass-Ceramic Articles Formed Therefrom with Improved Mechanical Durability - Patent application

Abstract

The glass-ceramic article includes 60 mol% to 72 mol% SiO2, 2.5 mol% to 8 mol% Al2O3, 17 mol% to 26 mol% Li2O, 0.2 mol% to 4 mol% ZrO2, and 0.5 mol% to 2 mol% P2O5. The sum of the alkaline earth oxides and transition metal oxides in the glass-ceramic article may be 0.1 mol% to 6 mol%, the alkaline earth oxides being the sum of CaO, MgO, SrO, and BaO, and the transition metal oxides being the sum of La2O3, Y2O3, Ta2O5, and GeO2. The sum of the P2O5 and ZrO2 in the glass-ceramic article may be 1 mol% to 6 mol%. The glass-ceramic article may have a crystalline phase including lithium disilicate and petalite. The total amount of lithium disilicate and petalite in the crystalline phase of the glass-ceramic article may be greater than 50% by weight, based on the total weight of the crystalline phase.

Description

Priority

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Patent Application No. 63 / 212145, filed June 18, 2021, the contents of which are relied upon and incorporated herein by reference in their entirety. [Technical field]

[0002] The present specification relates to precursor glass compositions and glass-ceramic articles, and more particularly to precursor glass compositions and ion-exchangeable glass-ceramic articles formed therefrom. [Background technology]

[0003] Glass articles, such as cover glass, glass backplanes, and housings, are used in both consumer and commercial electronic devices, such as smartphones, tablets, portable media players, personal computers, and cameras. Due to the portable nature of these portable devices, they and the glass articles contained therein are particularly susceptible to being accidentally dropped onto hard surfaces, such as the ground. Furthermore, glass articles, such as cover glass, may be provided with "touch" functionality, where the glass article necessarily comes into contact with various objects, including a user's finger and / or stylus instrument. Thus, the glass article must be tough enough to withstand accidental drops and everyday contact without sustaining damage, such as scratches. Indeed, scratches occurring on the surface of a glass article may reduce the strength of the glass article, as they may act as initiation points for cracks that result in catastrophic failure of the glass.

[0004] Additionally, the optical characteristics of the glass article, such as its transmittance, may be an important consideration when the glass article is incorporated as a cover glass in a portable electronic device. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, there is a need for alternative materials that have improved mechanical properties relative to glass, while also having similar optical characteristics to glass. [Means for solving the problem]

[0006] According to a first aspect A1, the glass-ceramic article may comprise 60 mol% to 72 mol% SiO2, 2.5 mol% to 8 mol% Al2O3, 17 mol% to 26 mol% Li2O, 0.2 mol% to 4 mol% ZrO2, and 0.5 mol% to 2 mol% P2O5, with alkaline earth oxides + transition metal oxides being 0.1 mol% to 6 mol%, and the alkaline earth oxides being selected from the group consisting of CaO, MgO, SrO, and the like. the transition metal oxide is the sum of La2O3, YO, Ta2O5, and GeO2; P2O5+ZrO2 is greater than or equal to 1 mol% and less than or equal to 6 mol%; (SiO2+Al2O3) / (P2O5+ZrO2) is greater than or equal to 12 mol% and less than or equal to 34 mol%; and the glass-ceramic article has a crystalline phase comprising lithium disilicate and petalite, wherein the total amount of lithium disilicate and petalite is greater than 50 mass% based on the total mass of the crystalline phase.

[0007] A second aspect A2 includes the glass-ceramic article according to the first aspect A1, wherein the glass-ceramic article includes greater than or equal to 0.5 mol % and less than or equal to 4 mol % ZrO2.

[0008] A third aspect A3 includes a glass-ceramic article according to the first aspect A1 or the second aspect A2, wherein the alkaline earth oxides plus transition metal oxides is 0.1 mol % or more and 5 mol % or less.

[0009] A fourth aspect A4 includes the glass-ceramic article according to any one of the first through third aspects A1-A3, wherein P2O5+ZrO2 is equal to or greater than 2 mol % and equal to or less than 5 mol %.

[0010] A fifth aspect A5 includes the glass-ceramic article according to any one of the first through fourth aspects A1-A4, wherein (SiO2+Al2O3) / (P2O5+ZrO2) is equal to or greater than 14 mol% and equal to or less than 32 mol%.

[0011] A sixth embodiment A6 includes a glass-ceramic article according to any one of the first through fifth embodiments A1-A5, wherein the molar ratio of Li2O to Al2O3 is 2 or greater and 12 or less.

[0012] A seventh embodiment A7 includes the glass-ceramic article according to the sixth embodiment A6, wherein the molar ratio of Li2O to Al2O3 is 4 or greater and 10 or less.

[0013] An eighth embodiment A8 includes the glass-ceramic article according to any one of the first through seventh embodiments A1-A7, wherein the molar ratio of Li2O to SiO2 is greater than or equal to 0.25 and less than or equal to 0.5.

[0014] A ninth embodiment A9 includes the glass-ceramic article according to the eighth embodiment A8, wherein the molar ratio of Li2O to SiO2 is greater than or equal to 0.25 and less than or equal to 0.4.

[0015] A tenth embodiment A10 includes the glass-ceramic article according to any one of the first through ninth embodiments A1-A9, wherein the glass-ceramic article includes greater than or equal to 2.5 mol % and less than or equal to 6 mol % Al2O3.

[0016] An eleventh aspect A11 includes the glass-ceramic article according to any one of the first through tenth aspects A1-A10, wherein the glass-ceramic article includes greater than or equal to 18 mol % and less than or equal to 24 mol % Li2O.

[0017] A twelfth aspect A12 includes the glass-ceramic article according to any one of the first through eleventh aspects A1-A11, wherein the glass-ceramic article includes greater than or equal to 0.7 mol % and less than or equal to 1.75 mol % P2O5.

[0018] A thirteenth embodiment A13 includes the glass-ceramic article according to any one of the first through twelfth embodiments A1-A12, wherein R2O is equal to or greater than 17 mol % and equal to or less than 30 mol %, R2O being the sum of Li2O, Na2O, and K2O.

[0019] A fourteenth embodiment A14 includes the glass-ceramic article according to any one of the first through thirteenth embodiments A1-A13, wherein the glass-ceramic article includes greater than or equal to 0 mol % and less than or equal to 6 mol % Na2O, and greater than or equal to 0 mol % and less than or equal to 6 mol % K2O.

[0020] A fifteenth embodiment A15 includes the glass-ceramic article according to any one of the first through fourteenth embodiments A1-A14, wherein the glass-ceramic article includes ≧0 mol % and ≦8 mol % CaO, ≧0 mol % and ≦8 mol % MgO, ≧0 mol % and ≦8 mol % SrO, and ≧0 mol % and ≦8 mol % BaO.

[0021] A sixteenth embodiment A16 includes the glass-ceramic article according to any one of the first through fifteenth embodiments A1-A15, wherein the glass-ceramic article includes ≧0 mol % and ≦4 mol % La2O3, ≧0 mol % and ≦6 mol % Y2O3, ≧0 mol % and ≦3 mol % Ta2O5, and ≧0 mol % and ≦2 mol % GeO2.

[0022] A seventeenth aspect A17 includes the glass-ceramic article according to any one of the first through sixteenth aspects A1-A16, wherein the glass-ceramic article includes greater than or equal to 0 mol % and less than or equal to 8 mol % B2O3.

[0023] An eighteenth aspect A18 includes the glass-ceramic article according to any one of the first through seventeenth aspects A1-A17, wherein the glass-ceramic article includes greater than or equal to 0 mol % and less than or equal to 10 mol % ZnO.

[0024] A nineteenth embodiment A19 includes the glass-ceramic article according to any one of the first through eighteenth embodiments A1-A18, wherein the crystalline phase lithium disilicate and petalite particles have a grain size of 10 nm or more and 100 nm or less.

[0025] A twentieth embodiment, A20, includes the glass-ceramic article according to any one of the first through nineteenth embodiments, A1-A19, wherein the crystalline phase of the glass-ceramic article further includes lithium metasilicate, β-quartz, cristobalite, or a combination thereof.

[0026] A twenty-first aspect A21 includes the glass-ceramic article according to any one of the first to twentieth aspects A1-A20, wherein the average transmittance of the glass-ceramic article is greater than or equal to 50% and less than or equal to 95% over the wavelength range from 400 nm to 800 nm, measured at an article thickness of 0.8 mm.

[0027] A twenty-second embodiment, A22, relates to the fracture toughness, K, of a glass-ceramic article, as measured by the chevron notched short bar method. IC , but 1.0MPa m 1 / 2 The present invention includes a glass-ceramic article according to any one of the first to twenty-first aspects A1 to A21.

[0028] A twenty-third aspect A23 includes the glass-ceramic article according to any one of the first through twenty-second aspects A1-A22, wherein the glass-ceramic article has a modulus of elasticity of 90 GPa or greater.

[0029] A twenty-fourth aspect, A24, includes the glass-ceramic article according to any one of the first through twenty-third aspects, A1-A23, wherein the glass-ceramic article is chemically strengthened in an ion exchange bath at a temperature of 350° C. or more and 500° C. or less for a period of 2 hours or more and 24 hours or less to form an ion-exchanged glass-ceramic article.

[0030] A twenty-fifth embodiment A25 includes the glass-ceramic article according to the twenty-fourth embodiment A24, wherein the ion exchange bath includes KNO3.

[0031] A twenty-sixth embodiment A26 includes the glass-ceramic article according to the twenty-fifth embodiment A25, wherein the ion exchange bath further includes NaNO 3 .

[0032] A twenty-seventh embodiment, A27, comprises the glass-ceramic article according to any one of the twenty-fourth through twenty-sixth embodiments, A24-A26, wherein the glass-ceramic article has a maximum central tension of 30 MPa or greater.

[0033] A twenty-eighth embodiment, A28, includes the glass-ceramic article according to any one of the twenty-fourth through twenty-seventh embodiments, A24-A27, wherein the glass-ceramic article has a surface compressive stress of 80 MPa or greater.

[0034] A twenty-ninth embodiment, A29, includes the glass-ceramic article according to any one of the twenty-fourth through twenty-eighth embodiments, A24-A28, wherein the glass-ceramic article has a compression depth of 0.025t or greater.

[0035] A thirtieth embodiment, A30, includes the glass-ceramic article according to any one of the twenty-fourth through twenty-ninth embodiments, A24-A29, wherein the glass-ceramic article has a sodium ion penetration depth of greater than or equal to 0.025t and less than or equal to 0.28t.

[0036] A thirty-first embodiment, A31, includes the glass-ceramic article according to any one of the twenty-fourth through thirtieth embodiments, A24-A30, wherein the glass-ceramic article has a potassium ion penetration depth greater than or equal to 0t and less than or equal to 0.01t.

[0037] According to a thirty-second aspect A32, the glass composition may include 60 mol% or more and 72 mol% or less of SiO2, 2.5 mol% or more and 8 mol% or less of Al2O3, 2.5 mol% or more and 8 mol% or less of Al2O3, 1.5 mol% or more and 4 mol% or less of ZrO2, and 0.5 mol% or more and 2 mol% or less of P2O5, where the alkaline earth oxides + transition metal oxides are 0.1 mol% or more and 6 mol% or less, the alkaline earth oxides being the sum of CaO, MgO, SrO, and BaO, the transition metal oxides being the sum of La2O3, YO3, Ta2O5, and GeO2, and P2O5 + ZrO2 being 1 mol% or more and 6 mol% or less.

[0038] A thirty-third embodiment A33 includes a glass composition according to the thirty-second embodiment A32, in which P2O5+ZrO2 is equal to or greater than 1 mol % and equal to or less than 6 mol %.

[0039] A thirty-fourth embodiment A34 includes a glass composition according to the thirty-second embodiment A32 or the thirty-third embodiment A33, in which P2O5+ZrO2 is equal to or greater than 2 mol % and equal to or less than 5 mol %.

[0040] A thirty-fifth embodiment, A35, comprises the glass composition according to any one of the thirty-second to thirty-fourth embodiments, A32-A34, in which the molar ratio of Li2O to Al2O3 is 2 or more and 12 or less.

[0041] A thirty-sixth embodiment, A36, includes a glass composition according to the thirty-fifth embodiment, A35, in which the molar ratio of Li2O to Al2O3 is 4 or more and 10 or less.

[0042] A thirty-seventh embodiment A37 comprises the glass composition according to any one of the thirty-second to thirty-sixth embodiments A32-A36, in which the molar ratio of Li2O to SiO2 is equal to or greater than 0.25 and equal to or less than 0.5.

[0043] A thirty-eighth embodiment, A38, includes the glass composition according to the thirty-seventh embodiment, A37, in which the molar ratio of Li2O to SiO2 is greater than or equal to 0.25 and less than or equal to 0.4.

[0044] A thirty-ninth embodiment, A39, comprises the glass composition according to any one of the thirty-second to thirty-eighth embodiments, A32-A38, in which the glass composition comprises 2.5 mol % or more and 6 mol % or less of Al2O3.

[0045] A fortieth embodiment A40 comprises the glass composition according to any one of the thirty-second to thirty-ninth embodiments A32-A39, in which the glass composition comprises 18 mol % or more and 24 mol % or less of Li2O.

[0046] A forty-first embodiment A41 comprises the glass composition according to any one of the thirty-second to fortieth embodiments A32-A40, in which the glass composition comprises 0.7 mol % or more and 1.75 mol % or less of P2O5.

[0047] A forty-second embodiment A42 includes the glass composition according to any one of the thirty-second to forty-first embodiments A32 to A41, in which R2O is 17 mol % or more and 30 mol % or less, and R2O is the sum of Li2O, Na2O, and K2O.

[0048] A forty-third embodiment A43 includes a glass composition according to any one of the thirty-second to forty-second embodiments A32-A42, in which the glass composition includes 0 mol % or more and 8 mol % or less of CaO, 0 mol % or more and 8 mol % or less of MgO, 0 mol % or more and 8 mol % or less of SrO, and 0 mol % or more and 8 mol % or less of BaO.

[0049] A forty-fourth aspect, A44, comprises a glass composition according to any one of the thirty-second to forty-third aspects, A32-A43, in which the glass composition comprises 0 mol % or more and 4 mol % or less of La2O3, 0 mol % or more and 6 mol % or less of Y2O3, 0 mol % or more and 3 mol % or less of Ta2O5, and 0 mol % or more and 2 mol % or less of GeO2.

[0050] A forty-fifth embodiment, A45, comprises the glass composition according to any one of the thirty-second to forty-fourth embodiments, A32-A44, in which the glass composition comprises 0 mol % or more and 8 mol % or less of B2O3.

[0051] A forty-sixth aspect A46 comprises the glass composition according to any one of the thirty-second to forty-fifth aspects A32-A45, in which the glass composition comprises 0 mol % or more and 10 mol % or less of ZnO.

[0052] A forty-seventh aspect, A47, is a glass-ceramic article made by heating a precursor glass article in a furnace to a nucleation temperature at a rate of ≧1° C. / min and ≦10° C. / min, wherein the precursor glass article is made from a precursor glass composition including ≧60 mol% and ≦72 mol% SiO2, ≧2.5 mol% and ≦8 mol% Al2O3, ≧17 mol% and ≦26 mol% Li2O, ≧0.5 mol% and ≦4 mol% ZrO2, and ≧0.5 mol% and ≦2 mol% P2O5, wherein alkaline earth oxides plus transition metal oxides are ≧0.1 mol% and ≦6 mol%, wherein the alkaline earth oxides are the sum of CaO, MgO, SrO, and BaO, wherein the transition metal oxides are the sum of La2O3, YO3, Ta2O5, and GeO2, and wherein P2O5+ZrO2 is ≧1 mol% and ≦6 mol%, , (SiO2+Al2O3) / (P2O5+ZrO2) is 12 mol% or more and 34 mol% or less; maintaining the precursor glass article at a nucleation temperature in a furnace for a period of 0.1 hours or more and 8 hours or less to produce a nucleated crystallizable glass article; heating the nucleated crystallizable glass article in a furnace to a crystallization temperature at a rate of 1°C / min or more and 10°C / min or less; maintaining the nucleated crystallizable glass article in a furnace at a crystallization temperature for a period of 0.1 hours or more and 8 hours or less to produce a glass-ceramic article, the glass-ceramic article having a crystalline phase comprising lithium disilicate and petalite, the total amount of lithium disilicate and petalite being greater than 50% by weight, based on the total weight of the crystalline phases; and cooling the glass-ceramic article to room temperature.

[0053] A forty-eighth embodiment, A48, includes the glass-ceramic article according to the forty-seventh embodiment, A47, wherein the average transmittance of the glass-ceramic article is greater than or equal to 50% and less than or equal to 95% over the wavelength range from 400 nm to 800 nm, measured at an article thickness of 0.8 mm.

[0054] The forty-ninth embodiment A49 is a glass-ceramic article having a fracture toughness K measured by a small square bar method with chevron notches. IC , but 1.0MPa m 1 / 2 The above includes a glass-ceramic article according to the forty-seventh embodiment A47 or the forty-eighth embodiment A48.

[0055] A fiftieth embodiment, A50, includes the glass-ceramic article according to any one of the forty-seventh through forty-ninth embodiments, A47-A49, wherein the glass-ceramic article has a modulus of elasticity of 90 GPa or greater.

[0056] A fifty-first embodiment, A51, includes a glass-ceramic article according to any one of the forty-seventh to fiftieth embodiments, A47-A50, further comprising strengthening the glass-ceramic article in an ion exchange bath at a temperature of 350° C. or more and 500° C. or less for a period of 2 hours or more and 12 hours or less to form an ion-exchanged glass-ceramic article.

[0057] A fifty-second embodiment A52 includes the glass-ceramic article according to the fifty-first embodiment A51, wherein the ion exchange bath includes KNO3.

[0058] A fifty-third embodiment A53 includes the glass-ceramic article according to the fifty-second embodiment A52, wherein the ion exchange bath further comprises NaNO3.

[0059] A fifty-fourth embodiment, A54, comprises the glass-ceramic article according to any one of the fifty-first to fifty-third embodiments, A51-A53, wherein the glass-ceramic article has a maximum central tension of 30 MPa or greater.

[0060] A fifty-fifth embodiment, A55, includes the glass-ceramic article according to any one of the fifty-first through fifty-fourth embodiments, A51-A54, wherein the glass-ceramic article has a surface compressive stress of 80 MPa or greater.

[0061] A fifty-sixth embodiment, A56, includes the glass-ceramic article according to any one of the fifty-first through fifty-fifth embodiments, A51-A55, wherein the glass-ceramic article has a compression depth of 0.025t or greater.

[0062] A fifty-seventh embodiment, A57, includes the glass-ceramic article according to any one of the fifty-first through fifty-sixth embodiments, A51-A56, wherein the glass-ceramic article has a sodium ion penetration depth greater than or equal to 0.025t and less than or equal to 0.28t.

[0063] A fifty-eighth embodiment, A58, includes the glass-ceramic article according to any one of the fifty-first through fifty-seventh embodiments, A51-A57, wherein the glass-ceramic article has a potassium ion penetration depth greater than or equal to 0t and less than or equal to 0.01t.

[0064] According to a fifty-ninth embodiment A59, a consumer electronics device may include a housing having a front, a back, and sides; electrical components at least partially disposed within the housing, the electrical components including at least a controller, a memory, and a display disposed at or adjacent to a front of the housing; and the glass-ceramic article of the first embodiment A1 disposed over the display and / or forming part of the housing.

[0065] Additional features and advantages of the glass-ceramic articles described herein are set forth in the following detailed description, and in part will be readily apparent to those skilled in the art from that description, or may be learned by practicing the embodiments described herein, including the following detailed description, claims, and accompanying drawings.

[0066] It will be understood that both the foregoing general description and the following detailed description describe various embodiments and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments described herein and, together with the description, serve to explain the principles and operation of the claimed subject matter. [Brief description of the drawings]

[0067] [Figure 1] FIG. 1 is a plan view of an electronic device incorporating any of the glass-ceramic articles according to one or more embodiments described herein. [Diagram 2] FIG. 2 is a perspective view of the electronic device of FIG. [Diagram 3] FIG. 1 is a plot of central tension (x-axis: ion-exchange time; y-axis: central tension) of comparative glass-ceramic articles made from comparative glass compositions and exemplary glass-ceramic articles made from precursor glass compositions according to one or more embodiments described herein. [Figure 4] FIG. 1 is a plot of central tension (x-axis: ion-exchange time; y-axis: central tension) of comparative glass-ceramic articles made from comparative glass compositions and exemplary glass-ceramic articles made from precursor glass compositions according to one or more embodiments described herein. [Diagram 5] FIG. 1 is a plot of central tension (x-axis: ion-exchange time; y-axis: central tension) of comparative glass-ceramic articles made from comparative glass compositions and exemplary glass-ceramic articles made from precursor glass compositions according to one or more embodiments described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0068] Reference will now be made in detail to various embodiments of the precursor glass composition and glass-ceramic articles formed therefrom with improved mechanical durability. According to embodiments, the glass-ceramic article comprises SiO2 of 60 mol% or more and 72 mol% or less, Al2O3 of 2.5 mol% or more and 8 mol% or less, Li2O of 17 mol% or more and 26 mol% or less, ZrO2 of 0.2 mol% or more and 4 mol% or less, and P2O5 of 0.5 mol% or more and 2 mol% or less. The sum of alkaline earth oxides and transition metal oxides in the glass-ceramic article may be 0.1 mol% to 6 mol%, the alkaline earth oxides being the sum of CaO, MgO, SrO, and BaO, and the transition metal oxides being the sum of La2O3, Y2O3, Ta2O5, and GeO2. The sum of P2O5 and ZrO2 in the glass-ceramic article may be 1 mol% to 6 mol%. The glass-ceramic article may have a crystalline phase including lithium disilicate and petalite. The total amount of lithium disilicate and petalite in the crystalline phase of the glass-ceramic article can be greater than 50 weight percent, based on the total weight of the crystalline phase.Various embodiments of precursor glass compositions and methods of forming ion-exchangeable glass-ceramic articles therefrom are described herein with specific reference to the accompanying drawings.

[0069] Ranges may be expressed herein as from "about" one particular value, and / or to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values ​​are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another embodiment. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0070] Any directional terms used herein - e.g., up, down, right, left, front, back, upper and bottom - are used only with reference to the drawings depicted and are not intended to imply absolute orientation.

[0071] Unless otherwise expressly stated, it is never intended that any method described herein be construed as requiring that its steps be performed in a particular order, or that any particular orientation of any apparatus be required. Thus, where a method claim does not actually recite an order in which its steps must be followed, or an apparatus claim does not actually recite an order or orientation for individual components, or where it is otherwise specifically stated in the claim or description that the steps are to be limited to a particular order, or where a particular order or orientation for the apparatus components is not recited, no order or orientation is ever intended to be implied. This applies to any possible non-expressive criteria of interpretation, including sequence of steps, flow of operations, order of components, or orientation of components; obvious meanings derived from grammatical construction or punctuation; and logical matters regarding the number or type of embodiments described in the specification.

[0072] As used herein, nouns include plural referents unless the context clearly indicates otherwise. Thus, for example, a reference to a component includes aspects having two or more of such components unless the context clearly indicates otherwise.

[0073] The term "substantially free," when used to describe the concentration and / or absence of a particular component in a precursor glass composition and the resulting glass-ceramic article, means that the component is not intentionally added to the precursor glass composition and the resulting glass-ceramic article. However, the precursor glass composition and the resulting glass-ceramic article may contain trace amounts of the component as a contaminant or admixture in amounts less than 0.1 mole percent.

[0074] The terms "0 mol %" and "free," when used to describe the concentration and / or absence of a particular component in the precursor glass composition and the resulting glass-ceramic article, mean that the component is not present in the precursor glass composition and the resulting glass-ceramic article.

[0075] In the embodiments of the precursor glass compositions and resulting glass-ceramic articles described herein, concentrations of components (e.g., SiO, AlO, etc.) are specified in mole percent (mol%) on an oxide basis, unless otherwise specified.

[0076] The term "fracture toughness (K IC The term "fracture toughness" refers to the ability of a glass composition to resist fracture. Fracture toughness is determined by the K IC The fracture toughness test methods described herein are not suitable for glass that has been subjected to IOX processing. However, fracture toughness measurements made as described herein on the same glass (e.g., glass substrate) before IOX processing correlate with fracture toughness after IOX processing and are therefore used as such. IC The chevron notched small square bar (CNSB) method used to measure the Y * mis disclosed in Reddy, KPR et al., "Fracture Toughness Measurement of Glass and Ceramic Materials Using Chevron-Notched Specimens," J. Am. Ceram. Soc., 71 [6], C-310-C-313 (1988), except that it is calculated using Equation 5 in Bubsey, RT et al., "Closed-Form Expressions for Crack-Mouth Displacement and Stress Intensity Factors for Chevron-Notched Short Bar and Short Rod Specimens Based on Experimental Compliance Measurements," NASA Technical Memorandum 83796, pp. 1-30 (October 1992). IC The double-torsion technique and fixture utilized to measure the K values ​​are described in Shyam, A. and Lara-Curzio, E., "The double-torsion testing technique for determination of fracture toughness and slow crack growth of materials: A review," J. Mater. Sci., Vol. 41, pp. 4093-4104, (2006). The double-torsion method generally produces slightly higher K values ​​than the chevron notched small square bar method. IC Unless otherwise stated, all fracture toughness values ​​were measured by the Chevron Notched Small Square Bar (CNSB) method.

[0077] The transmittance data (total transmittance and diffuse transmittance) were measured on a Lambda 950 UV / Vis spectrophotometer manufactured by PerkinElmer Inc. (Waltham, Massachusetts, USA). The Lambda 950 instrument was equipped with a 150 mm linear sphere. Data were collected using an open beam baseline at the sample position and a Spectralon® reference reflectance disk. For total transmittance (Total Tx), the sample is fixed at the entry point of the integrating sphere. For diffuse transmittance (Diffuse Tx), the Spectralon reference reflectance disk above the exit port of the sphere is removed to allow the on-axis light to exit the sphere and enter the light trap. With no sample present, a zero offset measurement of the diffuse portion is taken to determine the efficiency of the light trap. To correct for diffuse transmittance measurements, the formula: Diffuse Tx=Diffuse 測定 -(Zero Offset * Subtract the zero offset contribution from the sample measurements using (%Diffuse Tx / %Total Tx). Measure the scattering ratio for all wavelengths as (%Diffuse Tx / %Total Tx).

[0078] The term "average transmittance" as used herein refers to the average of transmittance measurements made within a given wavelength range, with each integer wavelength weighted equally. In the embodiments described herein, "average transmittance" is reported over the wavelength range of 400 nm to 800 nm, inclusive.

[0079] The term "transparent," when used to describe a glass-ceramic article formed from the precursor glass compositions described herein, means that the glass-ceramic article has an average transmittance of 85% or greater when measured at normal incidence for light in the wavelength range of 400 nm to 800 nm (endpoints included) at an article thickness of 0.8 mm.

[0080] The term "transparent haze," when used to describe a glass-ceramic article formed from the precursor glass compositions described herein, means that the glass-ceramic article has an average transmission of greater than or equal to 50% and less than 85%, measured at normal incidence for light in the wavelength range of 400 nm to 800 nm (endpoints included) at an article thickness of 0.8 mm.

[0081] The term "semi-transparent," when used to describe a glass-ceramic article formed from the precursor glass compositions described herein, means that the glass-ceramic article has an average transmittance of greater than or equal to 20% and less than 50%, measured at normal incidence for light in the wavelength range of 400 nm to 800 nm (endpoints included) at an article thickness of 0.8 mm.

[0082] The term "opaque", when used to describe a glass-ceramic article formed from the precursor glass compositions described herein, means that the glass-ceramic article has an average transmission of less than 20% when measured at normal incidence for light in the wavelength range of 400 nm to 800 nm (endpoints included) at an article thickness of 0.8 mm.

[0083] As used herein, the term "melting point" refers to the temperature at which the viscosity of the precursor glass composition is 200 poise.

[0084] As used herein, the term "softening point" refers to the point at which the viscosity of the precursor glass composition is less than 1×10 7.6 The softening point is a function of temperature similar to ASTM C1351M, which is 10 7 From 10 9 It is measured according to the parallel plate viscometry method which measures the viscosity of inorganic glasses in poise.

[0085] The term "liquidus viscosity" as used herein refers to the viscosity of a precursor glass composition at the onset of devitrification (ie, the liquidus temperature as determined by gradient furnace measurement per ASTM C829-81).

[0086] The term "liquidus temperature" as used herein refers to the temperature at which the precursor glass composition begins to devitrify as measured according to the gradient furnace method per ASTM C829-81.

[0087] The elastic modulus (also referred to as Young's modulus) of the glass-ceramic articles as described herein is given in units of gigapascals (GPa) and is measured according to ASTM C623.

[0088] The modulus of rigidity of the glass-ceramic articles as described herein is given in units of gigapascals (GPa) and is measured according to ASTM C623.

[0089] Poisson's ratio as described herein is measured in accordance with ASTM C623.

[0090] As used herein, the terms "coefficient of linear thermal expansion" and "CTE" refer to a temperature range of 25° C. to 300° C., as measured in accordance with ASTM E228-85, and expressed as a function of "×10 -7 / ℃".

[0091] Surface compressive stress is measured with a surface stress meter (FSM), such as a commercially available instrument, such as the FSM-6000 manufactured by Orihara Seisakusho Co., Ltd. (Japan). Surface stress measurement relies on the measurement of the stress optical coefficient (SOC), which is related to the birefringence of the glass-ceramic article. SOC is then measured according to procedure C (glass disk method) described in ASTM standard C770-16, entitled "Standard Test Method for Measurement of Glass Stress-Optical Coefficient," the contents of which are incorporated herein in their entirety. Depth of compression (DOC) is measured with an FSM in conjunction with a scattered light polarimeter (SCALP), as known in the art. The FSM measures the depth of compression for potassium ion exchange, and the SCALP measures the depth of compression for sodium ion exchange. Maximum central tension (CT) values ​​are measured using SCALP technology, as known in the art. Values ​​reported herein for central tension (CT) refer to maximum central tension unless otherwise noted.

[0092] The terms "depth of compression" and "DOC" refer to the location in a glass-ceramic article where compressive stress transitions to tensile stress.

[0093] As used herein, the term "sodium ion penetration depth after ion exchange" refers to the depth within the glass-ceramic article to which sodium ions introduced during ion exchange diffuse into the glass-ceramic article (i.e., the distance from the surface of the glass article to the interior region) at which the concentration of sodium ions reaches a minimum, as determined by glow discharge optical emission spectroscopy (GD-OES).

[0094] As used herein, the term "potassium ion penetration depth after ion exchange" refers to the depth within the glass-ceramic article to which potassium ions introduced during ion exchange diffuse into the glass-ceramic article (i.e., the distance from the surface of the glass article to the interior region) at which the concentration of potassium ions reaches a minimum, as determined by GD-OES.

[0095] As used herein, the term "particle size" refers to the average size of the largest dimension of a particle as measured using scanning electron microscopy as described in MN Rahaman, Ceramic Processing, CRC Press, 2007, p. 107.

[0096] The term "aspect ratio" as used herein refers to the average ratio of the largest dimension to the smallest dimension perpendicular to the largest dimension of a particle as measured using scanning electron microscopy, as described in M. N. Rahaman, Ceramic Processing, CRC Press, 2007, p. 107.

[0097] Electron diffraction images using scanning electron microscopy (SEM) as described herein were taken on a ZEISS GeminiSEM 500 scanning electron microscope at a working distance (WD) of 4.7 mm, an electron high tension (EHT) of 3.00, and in high vacuum mode.

[0098] As used herein, the term "precursor glass composition" refers to a glass composition that upon heat treatment forms a precursor glass article or a glass-ceramic article.

[0099] As used herein, the term "precursor glass article" refers to a glass article that contains one or more nucleating agents that, upon heat treatment, result in the nucleation of a crystalline phase.

[0100] As used herein, the term "glass-ceramic article" refers to an article formed by heat-treating a glass article formed from a precursor glass composition to induce nucleation of a crystalline phase. In embodiments, the glass-ceramic article has a crystallinity of about 1% to about 99%.

[0101] For ease of reading, the term "precursor glass composition" is referred to throughout this detailed description, however, it should be recognized that the glass-ceramic articles described herein are produced by heat-treating precursor glass articles formed from the precursor glass compositions.

[0102] Glass-ceramic articles generally have improved fracture toughness compared to articles formed from glasses due to the presence of crystalline grains (which impede crack growth) and the relatively high elastic modulus of the glass-ceramic articles. However, due to the inherent microstructure of glass-ceramic articles, it can be difficult to achieve the desired transparency. Furthermore, alkali oxides present in the precursor glass composition can be included in the crystalline phase after heat treatment and can be unavailable for ion exchange.

[0103] Disclosed herein are precursor glass compositions and glass-ceramic articles formed therefrom that alleviate the above-mentioned problems. Specifically, the precursor glass compositions described herein contain relatively high concentrations of Li2O, Al2O3, K2O, P2O5, and ZrO2, resulting in transparent or transparent haze lithium disilicate and petalite-containing glass-ceramic articles with relatively high amounts of Li2O in the residual glass phase. Therefore, the residual glass phase will be easily ion-exchanged. Furthermore, the lithium disilicate and petalite nanocrystals have an interlocking microstructure, which may help improve the fracture toughness of the glass-ceramic article. "Interlocking microstructure" refers to elongated, randomly oriented nanocrystals that are interlocked and entangled with each other. This interlocking structure creates a tortuous path for the cracks and impedes the propagation of the cracks. The Al2O3 content, as well as the relatively high amounts of lithium disilicate and petalite (e.g., greater than 50% by weight, based on the total weight of the crystalline phases), may result in a relatively high modulus of elasticity compared to articles formed from glass alone. In addition, the precursor glass compositions described herein contain alkaline earth oxides (i.e., CaO, MgO, SrO, BaO) and / or transition metal oxides (i.e., La2O3, YO3, Ta2O5, and GeO2), which may primarily partition into the residual glass and result in glass-ceramic articles having relatively high maximum central tensions.

[0104] The precursor glass compositions and glass-ceramic articles described herein may be described as lithium aluminosilicate precursor glass compositions and glass-ceramic articles, and include SiO2, Al2O3, and Li2O. In addition to SiO2, Al2O3, and Li2O, the precursor glass compositions and glass-ceramic articles described herein further include ZrO2 and P2O5 to achieve the desired lithium disilicate and petalite phase-containing crystal phases. The precursor glass compositions and glass-ceramic articles described herein further include alkaline earth oxides (i.e., CaO, MgO, SrO, BaO) and / or transition metal oxides (i.e., La2O3, YO3, Ta2O5, and GeO2) to increase the maximum central tension of the resulting glass-ceramic article.

[0105] SiO2 is the primary glass former in the precursor glass compositions described herein and may function to stabilize the network structure of the glass-ceramic article. The concentration of SiO2 in the precursor glass composition should be high enough (e.g., 60 mol% or more) to form a crystalline phase including lithium disilicate and petalite when the precursor glass composition is subjected to a heat treatment to convert the precursor glass composition into a glass-ceramic article. The concentration of SiO2 may be limited (e.g., 72 mol% or less) to control the melting point of the precursor glass composition, since the melting temperature of pure SiO2 or high SiO2 glasses is undesirably high. Therefore, limiting the concentration of SiO2 may help improve the meltability and formability of the resulting glass-ceramic article.

[0106] Thus, in embodiments, the precursor glass compositions and resulting glass-ceramic articles may comprise 60 mol% or more and 72 mol% or less of SiO2. In embodiments, the concentration of SiO2 in the precursor glass compositions and resulting glass-ceramic articles may be 60 mol% or more, 64 mol% or more, or even 66 mol% or more. In embodiments, the concentration of SiO2 in the precursor glass compositions and resulting glass-ceramic articles may be 72 mol% or less, or even 70 mol% or less. In embodiments, the concentration of SiO2 in the precursor glass compositions and resulting glass-ceramic articles may be 60 mol% or more and 72 mol% or less, 60 mol% or more and 70 mol% or less, 64 mol% or more and 72 mol% or more, 64 mol% or more and 70 mol% or more, 66 mol% or more and 72 mol% or less, or even 66 mol% or more and 70 mol% or less, or any and all ranges formed from any of these endpoints.

[0107] Al2O3 is a component of petalite and is included in the precursor glass compositions described herein to achieve this crystalline phase. Like SiO2, Al2O3 may stabilize the glass network, in addition to imparting improved mechanical properties and chemical durability to the resulting glass-ceramic article. The concentration of Al2O3 may also be adjusted to control the viscosity of the precursor glass composition. However, if the concentration of Al2O3 is too high, the viscosity of the melt may increase and the fraction of lithium disilicate nanocrystals may be reduced to the point where they cannot form an interlocking structure. The concentration of Al2O3 is adjusted to ensure that the resulting glass-ceramic article has lithium disilicate and the desired fracture toughness (e.g., 1.0 MPa m 1 / 2 The Al2O3 concentration should be sufficiently high (e.g., 2.5 mol % or more) to have a high Al2O3 content (e.g., greater than 8 mol %). However, if the concentration of Al2O3 is too high (e.g., greater than 8 mol %), the viscosity of the melt may increase, which may impair the formability of the resulting glass-ceramic article, and the nanocrystalline fraction of lithium disilicate may decrease.

[0108] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 2.5 mol% or more and 8 mol% or less Al2O3. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 2.5 mol% or more and 6 mol% or less Al2O3. In embodiments, the concentration of Al2O3 in the precursor glass compositions and the resulting glass-ceramic articles may be 2.5 mol% or more, 3 mol% or more, or even 3.5 mol% or more. In embodiments, the concentration of Al2O3 in the precursor glass compositions and the resulting glass-ceramic articles may be 8 mol% or less, 6 mol% or less, or even 4.5 mol% or less. In embodiments, the concentration of Al2O3 in the precursor glass compositions and the resulting glass-ceramic articles can be from 2.5 mol% to 8 mol%, from 2.5 mol% to 6 mol%, from 2.5 mol% to 4.5 mol%, from 3 mol% to 8 mol%, from 3 mol% to 6 mol%, from 3 mol% to 4.5 mol%, from 3 mol% to 8 mol%, from 3 mol% to 6 mol%, from 3 mol% to 4.5 mol%, from 3.5 mol% to 8 mol%, from 3.5 mol% to 6 mol%, or even from 3.5 mol% to 4.5 mol%, or any and all ranges formed from any of these endpoints.

[0109] Li2O is a component of lithium disilicate and petalite and is included in the precursor glass compositions described herein to achieve these desired phases. Li2O also aids in the ion exchangeability of the resulting glass-ceramic article. Li2O lowers the softening point of the precursor glass composition, thereby enhancing the formability of the resulting glass-ceramic article. The concentration of Li2O should be high enough (e.g., 17 mol% or more) so that the resulting glass-ceramic article has lithium disilicate and petalite in an amount of 50 mass% or more, based on the total mass of the crystalline phases. However, too high a concentration of Li2O (e.g., greater than 26 mol%) can undesirably increase the viscosity of the melt, thereby reducing the formability of the resulting precursor glass and glass-ceramic article.

[0110] Thus, in embodiments, the precursor glass compositions and the resulting glass-ceramic articles may comprise 17 mol% or more and 26 mol% or less Li2O. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may comprise 18 mol% or more and 24 mol% or less Li2O. In embodiments, the concentration of Li2O in the precursor glass compositions and the resulting glass-ceramic articles may be 17 mol% or more, 18 mol% or more, or even 20 mol% or more. In embodiments, the concentration of Li2O in the precursor glass compositions and the resulting glass-ceramic articles may be 26 mol% or less, 24 mol% or less, or even 22 mol% or less. In embodiments, the concentration of LiO in the precursor glass compositions and the resulting glass-ceramic articles can be from 17 mol% to 26 mol%, from 17 mol% to 24 mol%, from 17 mol% to 22 mol%, from 18 mol% to 26 mol%, from 18 mol% to 24 mol%, from 18 mol% to 22 mol%, from 20 mol% to 26 mol%, from 20 mol% to 24 mol%, or even from 20 mol% to 22 mol%, or any and all ranges formed from any of these endpoints.

[0111] In embodiments, the molar ratio of the concentration of LiO in the precursor glass composition and the resulting glass-ceramic article to the concentration of AlO in the precursor glass composition and the resulting glass-ceramic article (i.e., LiO (mol %) to AlO (mol %)) may be 2 or more and 12 or less to achieve the desired lithium disilicate and petalite-containing crystal phase. In embodiments, the molar ratio of LiO to AlO in the precursor glass composition and the resulting glass-ceramic article may be 4 or more and 10 or less. In embodiments, the molar ratio of LiO to AlO in the precursor glass composition and the resulting glass-ceramic article may be 2 or more, or even 4 or more. In embodiments, the molar ratio of LiO to AlO in the precursor glass composition and the resulting glass-ceramic article may be 12 or less, 10 or less, or even 8 or less. In embodiments, the molar ratio of LiO to AlO in the precursor glass compositions and the resulting glass-ceramic articles can be from 2 to 12, from 2 to 10, from 2 to 8, from 4 to 12, from 4 to 10, and even from 4 to 8, or any and all ranges formed from any of these endpoints.

[0112] In embodiments, the molar ratio of the concentration of Li2O in the precursor glass composition and the resulting glass-ceramic article to the concentration of SiO2 in the precursor glass composition and the resulting glass-ceramic article (i.e., Li2O (mol %) to SiO2 (mol %)) may be 0.25 or more and 0.5 or less to achieve the desired lithium disilicate and petalite-containing crystal phase. In embodiments, the molar ratio of Li2O to SiO2 in the precursor glass composition and the resulting glass-ceramic article may be 0.25 or more and 0.4 or less. In embodiments, the molar ratio of Li2O to SiO2 in the precursor glass composition and the resulting glass-ceramic article may be 0.25 or more and even 0.3 or more. In embodiments, the molar ratio of Li2O to SiO2 in the precursor glass composition and the resulting glass-ceramic article may be 0.5 or less, 0.4 or less, or even 0.35 or less. In embodiments, the molar ratio of LiO to SiO in the precursor glass compositions and the resulting glass-ceramic articles can be greater than or equal to 0.25 and less than or equal to 0.5, greater than or equal to 0.25 and less than or equal to 0.4, greater than or equal to 0.25 and less than or equal to 0.35, greater than or equal to 0.3 and less than or equal to 0.5, greater than or equal to 0.3 and less than or equal to 0.4, or even greater than or equal to 0.3 and less than or equal to 0.35, or any and all ranges formed from any of these endpoints.

[0113] The precursor glass compositions and resulting glass-ceramic articles described herein may further include alkali metal oxides other than Li2O, such as Na2O and / or K2O. Na2O reduces the melting point and improves the formability of the resulting glass-ceramic article, in addition to aiding in the ion-exchangeability of the resulting glass-ceramic article. In embodiments, the precursor glass compositions and resulting glass-ceramic articles may include 0 mol% or more and 6 mol% or less Na2O. In embodiments, the concentration of Na2O in the precursor glass compositions and resulting glass-ceramic articles may be 0 mol% or more, or even 1 mol% or more. In embodiments, the concentration of Na2O in the precursor glass compositions and resulting glass-ceramic articles may be 6 mol% or less, 5 mol% or less, 4 mol% or less, or even 3 mol% or less. In embodiments, the concentration of Na2O in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 1 mol% to 6 mol%, from 1 mol% to 5 mol%, from 1 mol% to 4 mol%, or even from 1 mol% to 3 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles can be substantially free or free of Na2O.

[0114] K2O promotes ion exchange, increases the compression depth, and reduces the melting point, improving the formability of the resulting glass-ceramic article. However, the addition of K2O may result in too low a surface compressive stress and melting point. In embodiments, the precursor glass composition and the resulting glass-ceramic article may contain 0 mol% or more and 6 mol% or less of K2O. In embodiments, the concentration of K2O in the precursor glass composition and the resulting glass-ceramic article may be 0 mol% or more, or even 1 mol% or more. In embodiments, the concentration of K2O in the precursor glass composition and the resulting glass-ceramic article may be 6 mol% or less, 5 mol% or less, 4 mol% or less, or even 3 mol% or less. In embodiments, the concentration of KO in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 1 mol% to 6 mol%, from 1 mol% to 5 mol%, from 1 mol% to 4 mol%, or even from 1 mol% to 3 mol%, or any and all subranges formed from any of these endpoints. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles can be substantially free or free of KO.

[0115] As used herein, R2O is the sum (mol %) of Li2O, Na2O, and K2O present in the precursor glass composition and the resulting glass-ceramic article (i.e., R2O=Li2O(mol %)+Na2O(mol %)+K2O(mol %)). Alkali oxides such as Li2O, Na2O, and K2O lower the softening point and forming temperature of the precursor glass composition, thereby offsetting the increase in the softening point and forming temperature of the precursor glass composition due to the high amount of SiO2 in the precursor glass composition. The softening point and forming temperature can be further lowered by including a combination of alkali oxides (e.g., two or more alkali oxides) in the precursor glass composition, a phenomenon referred to as the "mixed alkali effect." However, too much alkali oxide can increase the average thermal expansion coefficient of the precursor glass composition by more than 100×10 -7 / °C, which would be undesirable.

[0116] In embodiments, the concentration of R2O in the precursor glass compositions and the resulting glass-ceramic articles may be 17 mol% or more and 30 mol% or less. In embodiments, the concentration of R2O in the precursor glass compositions and the resulting glass-ceramic articles may be 17 mol% or more, 19 mol% or more, or even 21 mol% or more. In embodiments, the concentration of R2O in the precursor glass compositions and the resulting glass-ceramic articles may be 30 mol% or less, 27 mol% or less, or even 25 mol% or less. In embodiments, the concentration of R2O in the precursor glass compositions and the resulting glass-ceramic articles can be from 17 mol% to 30 mol%, from 17 mol% to 27 mol%, from 17 mol% to 25 mol%, from 19 mol% to 30 mol%, from 19 mol% to 27 mol%, from 19 mol% to 25 mol%, from 21 mol% to 30 mol%, from 21 mol% to 27 mol%, or even from 21 mol% to 25 mol%, or any and all ranges formed from any of these endpoints.

[0117] The precursor glass compositions and resulting glass-ceramic articles described herein further include ZrO2. ZrO2 may help reduce petalite grain size, which may be important for the formation of transparent or transparent haze glass-ceramic articles. ZrO2, like SiO2 and Al2O3, may act as a network former, thereby reducing devitrification during forming and improving the stability of the glass by lowering the liquidus temperature. The addition of ZrO2 may also improve the chemical durability of the resulting glass-ceramic article. In embodiments, the precursor glass compositions and resulting glass-ceramic articles may include 0.2 mol% or more and 4 mol% or less ZrO2. In embodiments, the precursor glass compositions and resulting glass-ceramic articles may include 0.5 mol% or more and 4 mol% or less ZrO2. In embodiments, the concentration of ZrO2 in the precursor glass compositions and resulting glass-ceramic articles may include 1.5 mol% or more and 4 mol% or less ZrO2. In embodiments, the concentration of ZrO2 in the precursor glass compositions and the resulting glass-ceramic articles may be 0.2 mol% or more, 0.5 mol% or more, 1 mol% or more, or even 1.5 mol% or more. In embodiments, the concentration of ZrO2 in the precursor glass compositions and the resulting glass-ceramic articles may be 4 mol% or less, or even 3.5 mol% or less. In embodiments, the concentration of ZrO2 in the precursor glass compositions and the resulting glass-ceramic articles may be 0.2 mol% or more and 4 mol% or less, 0.2 mol% or more and 3.5 mol% or more, 0.5 mol% or more and 4 mol% or less, 0.5 mol% or more and 3.5 mol% or more, 1 mol% or more and 4 mol% or less, 1 mol% or more and 3.5 mol% or more, 1.5 mol% or more and 4 mol% or less, or even 1.5 mol% or more and 3.5 mol% or less, or any and all ranges formed from any of these endpoints.

[0118] The precursor glass compositions and the resulting glass-ceramic articles described herein further comprise P2O5. P2O5 acts as a nucleating agent that causes bulk nucleation of crystalline phases in the glass, thereby converting the glass to a glass-ceramic article. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may comprise 0.5 mol% or more and 2 mol% or less of P2O5. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may comprise 0.7 mol% or more and 1.75 mol% or less of P2O5. In embodiments, the concentration of P2O5 in the precursor glass compositions and the resulting glass-ceramic articles may be 0.5 mol% or more, 0.7 mol% or more, or even 0.9 mol% or more. In embodiments, the concentration of P2O5 in the precursor glass compositions and the resulting glass-ceramic articles may be 2 mol% or less, 1.75 mol% or less, 1.5 mol% or less, or even 1.25 mol% or less. In embodiments, the concentration of P2O5 in the precursor glass compositions and the resulting glass-ceramic articles can be from 0.5 mol% to 2 mol%, from 0.5 mol% to 1.75 mol%, from 0.5 mol% to 1.5 mol%, from 0.5 mol% to 1.25 mol%, from 0.7 mol% to 2 mol%, from 0.7 mol% to 1.75 mol%, from 0.7 mol% to 1.5 mol%, from 0.7 mol% to 1.25 mol%, from 0.9 mol% to 2 mol%, from 0.9 mol% to 1.75 mol%, from 0.9 mol% to 1.5 mol%, or even from 0.9 mol% to 1.25 mol%, or any and all ranges formed from any of these endpoints.

[0119] In embodiments, the sum (mol %) of P2O5 and ZrO2 (i.e., P2O5(mol %)+ZrO2(mol %)) in the precursor glass composition and the resulting glass-ceramic article should be high enough (e.g., 1 mol % or more) to cause bulk nucleation of crystalline phases in the glass, thereby converting the glass to a glass-ceramic article. The sum of P2O5 and ZrO2 may be limited (e.g., 6 mol % or less) to produce a transparent or transparent haze glass-ceramic article. Thus, in embodiments, the sum of P2O5 and ZrO2 may be 1 mol % or more and 6 mol % or less. In embodiments, P2O5+ZrO2 in the precursor glass composition and the resulting glass-ceramic article may be 2 mol % or more and 5 mol % or less. In embodiments, P2O5+ZrO2 in the precursor glass composition and the resulting glass-ceramic article may be 1 mol % or more, or even 2 mol % or more. In embodiments, P2O5 + ZrO2 in the precursor glass compositions and the resulting glass-ceramic articles can be 6 mol% or less, 5 mol% or less, or even 4 mol% or less. In embodiments, P2O5 + ZrO2 in the precursor glass compositions and the resulting glass-ceramic articles can be greater than or equal to 1 mol% and less than or equal to 6 mol%, greater than or equal to 1 mol% and less than or equal to 5 mol%, greater than or equal to 1 mol% and less than or equal to 4 mol%, greater than or equal to 2 mol% and less than or equal to 6 mol%, greater than or equal to 2 mol% and less than or equal to 5 mol%, or even greater than or equal to 2 mol% and less than or equal to 4 mol%, or any and all ranges formed from any of these endpoints.

[0120] In embodiments, the molar ratio of the sum of SiO and AlO (i.e., SiO (mol%) + AlO (mol%)) to the sum of P2O5 and ZrO (i.e., P2O5 (mol%) + ZrO2 (mol%)), expressed as (SiO (mol%) + AlO (mol%)) / (P2O5 (mol%) + ZrO (mol%)), in the precursor glass composition and the resulting glass-ceramic article, may be greater than or equal to 12 mol% and less than or equal to 34 mol% to ensure the formation of the desired lithium disilicate and petalite phases. Without intending to be bound by theory, it is believed that when (SiO (mol%) + AlO (mol%)) / (P2O5 (mol%) + ZrO (mol%)) in the precursor glass composition and the resulting glass-ceramic article is greater than 34 mol%, other crystalline phases, such as quartz phase, will be formed. In embodiments, (SiO2(mol%)+Al2O3(mol%)) / (P2O5(mol%)+ZrO2(mol%)) in the precursor glass compositions and the resulting glass-ceramic articles may be 14 mol% or more and 32 mol% or less. In embodiments, (SiO2(mol%)+Al2O3(mol%)) / (P2O5(mol%)+ZrO2(mol%)) in the precursor glass compositions and the resulting glass-ceramic articles may be 12 mol% or more, 14 mol% or more, 16 mol% or more, 18 mol% or more, or even 20 mol% or more. In embodiments, (SiO2(mol%)+Al2O3(mol%)) / (P2O5(mol%)+ZrO2(mol%)) in the precursor glass compositions and the resulting glass-ceramic articles may be 34 mol% or less, 32 mol% or less, 30 mol% or less, or even 28 mol% or less.In embodiments, (SiO2 (mol %) + Al2O3 (mol %)) / (P2O5 (mol %) + ZrO2 (mol %)) in the precursor glass composition and the resulting glass-ceramic article is 12 mol% or more and 34 mol% or less, 12 mol% or more and 32 mol% or less, 12 mol% or more and 30 mol% or less, 12 mol% or more and 28 mol% or less, 14 mol% or more and 34 mol% or less, 14 mol% or more and 32 mol% or less, 14 mol% or more and 30 mol% or less, 14 mol% or more and 28 mol% or less, 16 mol% or more and 30 ... 4 mol% or less, 16 mol% or more and 32 mol% or less, 16 mol% or more and 30 mol% or more, 16 mol% or more and 28 mol% or less, 18 mol% or more and 34 mol% or less, 18 mol% or more and 32 mol% or more, 18 mol% or more and 30 mol% or more, 18 mol% or more and 28 mol% or less, 20 mol% or more and 34 mol% or less, 20 mol% or more and 32 mol% or more, 20 mol% or more and 30 mol% or more, or even 20 mol% or more and 28 mol% or less, or any and all ranges formed from any of these endpoints.

[0121] The precursor glass compositions and the resulting glass-ceramic articles described herein further include alkaline earth oxides and / or transition metal oxides, which may be primarily distributed in the residual glass phase during crystallization, thereby filling the glass network. Although alkali diffusivity during ion exchange may be slowed due to the presence of alkaline earth oxides and / or transition metal oxides in a more highly filled glass network, the ions exchanged into the glass network create a relatively higher stress per ion than a less filled glass network. The higher stress increases the maximum central tension of the resulting glass-ceramic article. Thus, the inclusion of alkaline earth oxides and / or transition metal oxides in the precursor glass composition will increase the maximum central tension of the resulting glass-ceramic article.

[0122] "Alkaline earth oxides" is the sum (mol%) of CaO, MgO, SrO, and BaO present in the precursor glass composition and the resulting glass-ceramic article (i.e., alkaline earth oxides=CaO(mol%)+MgO(mol%)+SrO(mol%)+BaO(mol%)). "Transition metal oxides" is the sum (mol%) of La2O3, YO3, Ta2O5, and GeO2 present in the precursor glass composition and the resulting glass-ceramic article (i.e., La2O3(mol%)+YO3(mol%)+Ta2O5(mol%)+GeO2(mol%)). In embodiments, the sum (mol%) of alkaline earth oxides and transition metal oxides (i.e., alkaline earth oxides(mol%)+transition metal oxides(mol%)) in the precursor glass composition and the resulting glass-ceramic article may be 0.1 mol% or more and 6 mol% or less. In embodiments, the sum of the alkaline earth oxides and transition metal oxides in the precursor glass composition and the resulting glass-ceramic article may be 0.1 mol% or more and 5 mol% or less. In embodiments, the sum of the alkaline earth oxides and transition metal oxides in the precursor glass composition and the resulting glass-ceramic article may be 0.1 mol% or more, 0.2 mol% or more, 0.5 mol% or more, 0.7 mol% or more, or even 1 mol% or more. In embodiments, the sum of the alkaline earth oxides and transition metal oxides in the precursor glass composition and the resulting glass-ceramic article may be 6 mol% or less, 5 mol% or less, 4 mol% or less, 3 mol% or less, or even 2 mol% or less.In embodiments, the sum of alkaline earth oxides and transition metal oxides in the precursor glass composition and the resulting glass-ceramic article is 0.1 mol % or more and 6 mol % or less, 0.1 mol % or more and 5 mol % or less, 0.1 mol % or more and 4 mol % or less, 0.1 mol % or more and 3 mol % or less, 0.1 mol % or more and 2 mol % or less, 0.2 mol % or more and 6 mol % or less, 0.2 mol % or more and 5 mol % or less, 0.2 mol % or more and 4 mol % or less, 0.2 mol % or more and 3 mol % or less, 0.2 mol % or more and 2 mol % or less, 0.5 mol % or more and 6 mol % or less, 0.5 mol % or more and 6 mol % or less, 0.5 mol % or more and 5 mol % or less, 0.1 mol % or more and 4 mol % or less, 0.1 mol % or more and 3 mol % or less, 0.1 mol % or more and 2 mol % or less, 0.2 mol % or more and 6 mol % or less, 0.5 mol % or more and 5 mol % or less, 0.2 mol % or more and 4 mol % or less, 0.2 mol % or more and 3 mol % or less, 0.2 mol % or more and 2 mol % or less, 0.5 mol % or more and 6 mol % or less, 0.5 mol % or more and and 5 mol% or less, at least 0.5 mol% and 4 mol% or less, at least 0.5 mol% and 3 mol% or less, at least 0.5 mol% and 2 mol% or less, at least 0.7 mol% and 6 mol% or less, at least 0.7 mol% and 5 mol% or less, at least 0.7 mol% and 4 mol% or less, at least 0.7 mol% and 3 mol% or less, at least 0.7 mol% and 2 mol% or less, at least 1 mol% and 6 mol% or less, at least 1 mol% and 5 mol% or less, at least 1 mol% and 4 mol% or less, at least 1 mol% and 3 mol% or less, or even at least 1 mol% and 2 mol% or less, or any and all ranges formed from any of these endpoints.

[0123] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 8 mol% or less of CaO. In embodiments, the concentration of CaO in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 1 mol% or more, or even 2 mol% or more. In embodiments, the concentration of CaO in the precursor glass compositions and the resulting glass-ceramic articles may be 8 mol% or less, 7 mol% or less, 6 mol% or less, 5 mol% or less, or even 4 mol% or less. In embodiments, the concentration of CaO in the precursor glass composition and the resulting glass-ceramic article can be from 0 mol% to 8 mol%, from 0 mol% to 7 mol%, from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 1 mol% to 8 mol%, from 1 mol% to 7 mol%, from 1 mol% to 6 mol%, from 1 mol% to 5 mol%, from 1 mol% to 4 mol%, from 2 mol% to 8 mol%, from 2 mol% to 7 mol%, from 2 mol% to 6 mol%, from 2 mol% to 5 mol%, or even from 2 mol% to 4 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and the resulting glass-ceramic article can be substantially free or free of CaO.

[0124] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 8 mol% or less MgO. In embodiments, the concentration of MgO in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 1 mol% or more, or even 2 mol% or more. In embodiments, the concentration of MgO in the precursor glass compositions and the resulting glass-ceramic articles may be 8 mol% or less, 7 mol% or less, 6 mol% or less, 5 mol% or less, or even 4 mol% or less. In embodiments, the concentration of MgO in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 8 mol%, from 0 mol% to 7 mol%, from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 1 mol% to 8 mol%, from 1 mol% to 7 mol%, from 1 mol% to 6 mol%, from 1 mol% to 5 mol%, from 1 mol% to 4 mol%, from 2 mol% to 8 mol%, from 2 mol% to 7 mol%, from 2 mol% to 6 mol%, from 2 mol% to 5 mol%, or even from 2 mol% to 4 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles can be substantially free or free of MgO.

[0125] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 8 mol% or less SrO. In embodiments, the concentration of SrO in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 1 mol% or more, or even 2 mol% or more. In embodiments, the concentration of SrO in the precursor glass compositions and the resulting glass-ceramic articles may be 8 mol% or less, 7 mol% or less, 6 mol% or less, 5 mol% or less, or even 4 mol% or less. In embodiments, the concentration of SrO in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 8 mol%, from 0 mol% to 7 mol%, from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 1 mol% to 8 mol%, from 1 mol% to 7 mol%, from 1 mol% to 6 mol%, from 1 mol% to 5 mol%, from 1 mol% to 4 mol%, from 2 mol% to 8 mol%, from 2 mol% to 7 mol%, from 2 mol% to 6 mol%, from 2 mol% to 5 mol%, or even from 2 mol% to 4 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles can be substantially free or free of SrO.

[0126] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 8 mol% or less BaO. In embodiments, the concentration of BaO in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 1 mol% or more, or even 2 mol% or more. In embodiments, the concentration of BaO in the precursor glass compositions and the resulting glass-ceramic articles may be 8 mol% or less, 7 mol% or less, 6 mol% or less, 5 mol% or less, or even 4 mol% or less. In embodiments, the concentration of BaO in the precursor glass composition and the resulting glass-ceramic article can be from 0 mol% to 8 mol%, from 0 mol% to 7 mol%, from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 1 mol% to 8 mol%, from 1 mol% to 7 mol%, from 1 mol% to 6 mol%, from 1 mol% to 5 mol%, from 1 mol% to 4 mol%, from 2 mol% to 8 mol%, from 2 mol% to 7 mol%, from 2 mol% to 6 mol%, from 2 mol% to 5 mol%, or even from 2 mol% to 4 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and the resulting glass-ceramic article can be substantially free or free of BaO.

[0127] In embodiments, the concentration of alkaline earth oxides in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 0.1 mol% or more, 0.2 mol% or more, 0.5 mol% or more, 0.7 mol% or more, or even 1 mol% or more. In embodiments, the concentration of alkaline earth oxides in the precursor glass compositions and the resulting glass-ceramic articles may be 10 mol% or less, 6 mol% or less, 4 mol% or less, 3 mol% or less, or even 2 mol% or less. In embodiments, the concentration of alkaline earth oxides in the precursor glass composition and the resulting glass-ceramic article is from 0 mol% to 10 mol%, from 0 mol% to 6 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 0.1 mol% to 10 mol%, from 0.1 mol% to 6 mol%, from 0.1 mol% to 4 mol%, from 0.1 mol% to 3 mol%, from 0.1 mol% to 2 mol%, from 0.2 mol% to 10 mol%, from 0.2 mol% to 6 mol%, from 0.2 mol% to 4 mol%, from 0.2 mol% to 3 mol%, from 0.2 mol% to 2 mol% or less, 0.5 mol% to 10 mol%, 0.5 mol% to 6 mol%, 0.5 mol% to 4 mol%, 0.5 mol% to 3 mol%, 0.5 mol% to 2 mol%, 0.7 mol% to 10 mol%, 0.7 mol% to 6 mol%, 0.7 mol% to 4 mol%, 0.7 mol% to 3 mol%, 0.7 mol% to 2 mol%, 1 mol% to 10 mol%, 1 mol% to 6 mol%, 1 mol% to 4 mol%, 1 mol% to 3 mol%, or even 1 mol% to 2 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and the resulting glass-ceramic article may be substantially free or free of alkaline earth oxides.

[0128] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 4 mol% or less of La2O3. In embodiments, the concentration of La2O3 in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 0.1 mol% or more, 0.2 mol% or more, or even 0.5 mol% or more. In embodiments, the concentration of La2O3 in the precursor glass compositions and the resulting glass-ceramic articles may be 4 mol% or less, 3 mol% or less, 2 mol% or less, or even 1 mol% or less. In embodiments, the concentration of La2O3 in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 0 mol% to 1 mol%, from 0.1 mol% to 4 mol%, from 0.1 mol% to 3 mol%, from 0.1 mol% to 2 mol%, from 0.1 mol% to 1 mol%, from 0.2 mol% to 4 mol%, from 0.2 mol% to 3 mol%, from 0.2 mol% to 2 mol%, from 0.2 mol% to 1 mol%, from 0.5 mol% to 4 mol%, from 0.5 mol% to 3 mol%, from 0.5 mol% to 2 mol%, or even from 0.5 mol% to 1 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass compositions and resulting glass-ceramic articles may be substantially free or free of La2O3.

[0129] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 6 mol% or less Y2O3. In embodiments, the concentration of Y2O3 in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 0.1 mol% or more, 0.5 mol% or more, or even 1 mol% or more. In embodiments, the concentration of Y2O3 in the precursor glass compositions and the resulting glass-ceramic articles may be 6 mol% or less, 5 mol% or less, 4 mol% or less, 3 mol% or less, or even 2 mol% or less. In embodiments, the concentration of Y2O3 in the precursor glass composition and the resulting glass-ceramic article is from 0 mol% to 6 mol%, from 0 mol% to 5 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 0.1 mol% to 6 mol%, from 0.1 mol% to 5 mol%, from 0.1 mol% to 4 mol%, from 0.1 mol% to 3 mol%, from 0.1 ... % to 6 mol%, 0.5 mol% to 5 mol%, 0.5 mol% to 4 mol%, 0.5 mol% to 3 mol%, 0.5 mol% to 2 mol%, 1 mol% to 6 mol%, 1 mol% to 5 mol%, 1 mol% to 4 mol%, 1 mol% to 3 mol%, or even 1 mol% to 2 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and resulting glass-ceramic article may be substantially free or free of Y2O3.

[0130] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 3 mol% or less of Ta2O5. In embodiments, the concentration of Ta2O5 in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 0.1 mol% or more, 0.2 mol% or more, or even 0.5 mol% or more. In embodiments, the concentration of Ta2O5 in the precursor glass compositions and the resulting glass-ceramic articles may be 3 mol% or less, 2 mol% or less, or even 1 mol% or less. In embodiments, the concentration of Ta2O5 in the precursor glass composition and the resulting glass-ceramic article can be from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 0 mol% to 1 mol%, from 0.1 mol% to 3 mol%, from 0.1 mol% to 2 mol%, from 0.1 mol% to 1 mol%, from 0.2 mol% to 3 mol%, from 0.2 mol% to 2 mol%, from 0.2 mol% to 1 mol%, from 0.5 mol% to 3 mol%, from 0.5 mol% to 2 mol%, or even from 0.5 mol% to 1 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and the resulting glass-ceramic article can be substantially free or free of Ta2O5.

[0131] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 2 mol% or less of GeO2. In embodiments, the concentration of GeO2 in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 0.1 mol% or more, 0.2 mol% or more, or even 0.5 mol% or more. In embodiments, the concentration of GeO2 in the precursor glass compositions and the resulting glass-ceramic articles may be 2 mol% or less, or even 1 mol% or less. In embodiments, the concentration of GeO2 in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 2 mol%, from 0 mol% to 1 mol%, from 0.1 mol% to 2 mol%, from 0.1 mol% to 1 mol%, from 0.2 mol% to 2 mol%, from 0.2 mol% to 1 mol%, from 0.5 mol% to 2 mol%, or even from 0.5 mol% to 1 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles can be substantially free or free of GeO2.

[0132] In embodiments, the concentration of transition metal oxide in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, 0.1 mol% or more, 0.2 mol% or more, 0.5 mol% or more, 0.7 mol% or more, or even 1 mol% or more. In embodiments, the concentration of transition metal oxide in the precursor glass compositions and the resulting glass-ceramic articles may be 10 mol% or less, 6 mol% or less, 4 mol% or less, 3 mol% or less, or even 2 mol% or less. In embodiments, the concentration of transition metal oxide in the precursor glass composition and the resulting glass-ceramic article is from 0 mol% to 10 mol%, from 0 mol% to 6 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 0.1 mol% to 10 mol%, from 0.1 mol% to 6 mol%, from 0.1 mol% to 4 mol%, from 0.1 mol% to 3 mol%, from 0.1 mol% to 2 mol%, from 0.2 mol% to 10 mol%, from 0.2 mol% to 6 mol%, from 0.2 mol% to 4 mol%, from 0.2 mol% to 3 mol%, from 0.2 mol% to 2 ... mol% or less, 0.5 mol% to 10 mol%, 0.5 mol% to 6 mol%, 0.5 mol% to 4 mol%, 0.5 mol% to 3 mol%, 0.5 mol% to 2 mol%, 0.7 mol% to 10 mol%, 0.7 mol% to 6 mol%, 0.7 mol% to 4 mol%, 0.7 mol% to 3 mol%, 0.7 mol% to 2 mol%, 1 mol% to 10 mol%, 1 mol% to 6 mol%, 1 mol% to 4 mol%, 1 mol% to 3 mol%, or even 1 mol% to 2 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and the resulting glass-ceramic article may be substantially free or free of transition metal oxides.

[0133] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may include 0 mol% or more and 10 mol% or less of ZnO. In embodiments, the concentration of ZnO in the precursor glass compositions and the resulting glass-ceramic articles may be 0 mol% or more, or even 1 mol% or more. In embodiments, the concentration of ZnO in the precursor glass compositions and the resulting glass-ceramic articles may be 10 mol% or less, 6 mol% or less, 4 mol% or less, 3 mol% or less, or even 2 mol% or less. In embodiments, the concentration of ZnO in the precursor glass compositions and the resulting glass-ceramic articles can be from 0 mol% to 10 mol%, from 0 mol% to 6 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 1 mol% to 10 mol%, from 1 mol% to 6 mol%, from 1 mol% to 4 mol%, from 1 mol% to 3 mol%, or even from 1 mol% to 2 mol%, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass compositions and the resulting glass-ceramic articles can be substantially free or free of ZnO.

[0134] As used herein, RO is the sum (in mol%) of CaO, MgO, ZnO, SrO, and BaO present in the precursor glass composition and the resulting glass-ceramic article (i.e., RO=CaO(mol%)+MgO(mol%)+ZnO(mol%)+SrO(mol%)+BaO(mol%)). In embodiments, the concentration of RO in the precursor glass composition and the resulting glass-ceramic article may be 0 mol% or more, 0.1 mol% or more, 0.2 mol% or more, 0.5 mol% or more, 0.7 mol% or more, or even 1 mol% or more. In embodiments, the concentration of RO in the precursor glass composition and the resulting glass-ceramic article may be 10 mol% or less, 6 mol% or less, 4 mol% or less, 3 mol% or less, or even 2 mol% or less. In embodiments, the concentration of RO in the precursor glass composition and the resulting glass-ceramic article is from 0 mol% to 10 mol%, from 0 mol% to 6 mol%, from 0 mol% to 4 mol%, from 0 mol% to 3 mol%, from 0 mol% to 2 mol%, from 0.1 mol% to 10 mol%, from 0.1 mol% to 6 mol%, from 0.1 mol% to 4 mol%, from 0.1 mol% to 3 mol%, from 0.1 mol% to 2 mol%, from 0.2 mol% to 10 mol%, from 0.2 mol% to 6 mol%, from 0.2 mol% to 4 mol%, from 0.2 mol% to 3 mol%, from 0.2 mol% to 2 ... %, 0.5 mol % or less and 10 mol %, 0.5 mol % or more and 6 mol % or less, 0.5 mol % or more and 4 mol % or less, 0.5 mol % or more and 3 mol % or less, 0.5 mol % or more and 2 mol % or less, 0.7 mol % or more and 10 mol % or less, 0.7 mol % or more and 6 mol % or less, 0.7 mol % or more and 4 mol % or less, 0.7 mol % or more and 3 mol % or less, 0.7 mol % or more and 2 mol % or less, 1 mol % or more and 10 mol % or more, 1 mol % or more and 6 mol % or less, 1 mol % or more and 4 mol % or less, 1 mol % or more and 3 mol % or less, or even 1 mol % or more and 2 mol % or less, or any and all ranges formed from any of these endpoints.In embodiments, the precursor glass compositions and resulting glass-ceramic articles may be substantially free or free of RO.

[0135] The precursor glass compositions and the resulting glass-ceramic articles described herein may further include B2O3. B2O3 reduces the melting temperature of the precursor glass composition. Furthermore, adding B2O3 to the precursor glass composition helps achieve an interconnected crystal microstructure when the precursor glass composition is subjected to heat treatment to form the glass-ceramic article. In addition, B2O3 may improve the damage resistance of the resulting glass-ceramic article. If boron in the residual glass phase present after heat treatment is not charge balanced by alkali oxides or divalent cation oxides (such as MgO, CaO, SrO, BaO, and ZnO), the boron becomes trigonally coordinated (or tricoordinated boron), which opens up the structure of the glass. The network around these tricoordinated boron atoms is not as rigid as tetrahedrally coordinated (or tetracoordinated) boron. Without being bound by theory, it is believed that glass-ceramic articles containing tricoordinated boron can tolerate a certain degree of deformation before crack formation compared to tetracoordinated boron. By allowing some deformation, the Vickers indentation crack initiation threshold is increased. The fracture toughness of glass-ceramic articles containing tricoordinated boron will also be increased. B2O3 may be included (e.g., 0 mol% or more) to improve the formability and increase the fracture toughness of the resulting glass-ceramic article. However, if the concentration of B2O3 is too high, the chemical durability and liquidus viscosity may decrease, and the vaporization and evaporation of B2O3 during melting becomes difficult to control. Therefore, the concentration of B2O3 may be limited (e.g., 8 mol% or less) to maintain the chemical durability and manufacturability of the precursor glass composition.

[0136] In embodiments, the precursor glass composition and the resulting glass-ceramic article may include 0 mol% or more and 8 mol% or less of B2O3. In embodiments, the concentration of B2O3 in the precursor glass composition and the resulting glass-ceramic article may be 0 mol% or more, 1 mol% or more, or even 3 mol% or more. In embodiments, the concentration of B2O3 in the precursor glass composition and the resulting glass-ceramic article may be 8 mol% or less, or even 5 mol% or less. In embodiments, the concentration of B2O3 in the precursor glass composition and the resulting glass-ceramic article may be 0 mol% or more and 8 mol% or less, 0 mol% or more and 5 mol% or less, 1 mol% or more and 8 mol% or more, 1 mol% or more and 5 mol% or more, 3 mol% or more and 8 mol% or less, or even 3 mol% or more and 5 mol% or less, or any and all ranges formed from any of these endpoints. In embodiments, the precursor glass composition and the resulting glass-ceramic article may be substantially free or free of B2O3.

[0137] In embodiments, the precursor glass compositions and resulting glass-ceramic articles described herein may further include contaminants, such as TiO2, MnO, MoO3, WO3, CdO, As2O3, Sb2O3, sulfur-based compounds such as sulfates, halogens, or combinations thereof. In embodiments, the precursor glass compositions and resulting glass-ceramic articles may be substantially free or free of individual contaminants, combinations of contaminants, or all contaminants. For example, in embodiments, the precursor glass compositions and resulting glass-ceramic articles may be substantially free or free of TiO2, MnO, MoO3, WO3, CdO, As2O3, Sb2O3, sulfur-based compounds such as sulfates, halogens, or combinations thereof.

[0138] In embodiments, antimicrobial components, chemical fining agents, or other additional components may be included in the precursor glass compositions and the resulting glass-ceramic articles.

[0139] In embodiments, the liquidus temperature of the precursor glass composition may be greater than or equal to 900° C., or even greater than or equal to 1000° C. In embodiments, the liquidus temperature of the precursor glass composition may be less than or equal to 1200° C., or even less than or equal to 1100° C. In embodiments, the liquidus temperature of the precursor glass composition may be greater than or equal to 900° C. and less than or equal to 1200° C., greater than or equal to 900° C. and less than or equal to 1100° C., greater than or equal to 1000° C. and less than or equal to 1200° C., or even greater than or equal to 1000° C. and less than or equal to 1100° C., or any and all subranges formed from any of these endpoints.

[0140] The precursor glass articles described herein or glass-ceramic articles formed therefrom may be of any suitable thickness, which may vary depending on the particular application of the glass-ceramic article. In embodiments, the precursor glass articles or glass-ceramic articles formed therefrom may be of any suitable thickness, which may vary depending on the particular application of the glass-ceramic article. In embodiments, the precursor glass articles or glass-ceramic articles formed therefrom may be of any suitable thickness, which may vary depending on the particular application of the glass-ceramic article. In embodiments, the precursor glass articles or glass-ceramic articles formed therefrom may be of any suitable thickness, which may vary depending on the particular application of the glass-ceramic article. In embodiments, the precursor glass articles or glass-ceramic articles formed therefrom may be of any suitable thickness, which may vary depending on the particular application of the glass-ceramic article. In some embodiments, the thickness may be from 0 to 750 μm, from 750 μm to 6 mm, from 750 μm to 4 mm, from 750 μm to 2 mm, from 750 μm to 1 mm, from 1 mm to 6 mm, from 1 mm to 4 mm, from 1 mm to 2 mm, from 2 mm to 6 mm, from 2 mm to 4 mm, or even from 4 mm to 6 mm, or any and all sub-ranges formed from any of these endpoints.

[0141] As previously noted, glass-ceramic articles formed from the precursor glass compositions described herein may have increased fracture toughness such that the glass-ceramic articles are more damage tolerant. In embodiments, the glass-ceramic articles have a fracture toughness of 1.0 MPa m, as measured by the Chevron Notched Small Square Bar Method. 1 / 2 Fracture toughness K IC In an embodiment, the glass-ceramic article may have a modulus of 1.0 MPa m, as measured by the Chevron Notched Small Square Bar Method. 1 / 2 More than 1.1MPa m 1 / 2 or even 1.2MPa m 1 / 2 Fracture toughness K IC It may have.

[0142] In embodiments, the elastic modulus of the glass-ceramic article may be 90 GPa or more. In embodiments, the elastic modulus of the glass-ceramic article may be 90 GPa or more, or even 100 GPa or more. In embodiments, the elastic modulus of the glass-ceramic article may be 125 GPa or less, or even 115 GPa or less. In embodiments, the elastic modulus of the glass-ceramic article may be 90 GPa or more and 125 GPa or less, 90 GPa or more and 115 GPa or less, 100 GPa or more and 125 GPa or more and even 100 GPa or more and 115 GPa or less, or any and all subranges formed from any of these endpoints.

[0143] In embodiments, the precursor glass compositions and the resulting glass-ceramic articles may have a modulus of rigidity of 30 GPa or more, or even 40 GPa or more. In embodiments, the glass-ceramic articles may have a modulus of rigidity of 55 GPa or less, or even 45 GPa or less. In embodiments, the glass-ceramic articles may have a modulus of rigidity of 30 GPa or more and 55 GPa or less, 30 GPa or more and 45 GPa or less, 40 GPa or more and 55 GPa or less, or even 40 GPa or more and 45 GPa or less, or any and all subranges formed from any of these endpoints.

[0144] In embodiments, the average transmittance of the glass-ceramic article may be 50% or more and 95% or less of light over the wavelength range of 400 nm to 800 nm, measured at an article thickness of 0.8 mm. In embodiments, the average transmittance of the glass-ceramic article may be 50% or more, 60% or more, 70% or more, or even 80% or more of light over the wavelength range of 400 nm to 800 nm, measured at an article thickness of 0.8 mm. In embodiments, the average transmittance of the glass-ceramic article may be 95% or less, or even 90% or less of light over the wavelength range of 400 nm to 800 nm, measured at an article thickness of 0.8 mm. In embodiments, the average transmittance of the glass-ceramic article, measured at an article thickness of 0.8 mm, can be 50% or more and 95% or less, 50% or more and 90% or less, 60% or more and 95% or less, 60% or more and 90% or less, 70% or more and 95% or less, 70% or more and 90% or less, 80% or more and 95% or less, or even 80% or more and 90% or less, or any and all subranges formed from any of these endpoints, of light over the wavelength range of 400 nm to 800 nm. In embodiments, the glass-ceramic article can be transparent or transparent haze.

[0145] In embodiments, the Poisson's ratio of the glass-ceramic article may be greater than or equal to 0.17, or even greater than or equal to 0.19. In embodiments, the Poisson's ratio of the glass-ceramic article may be less than or equal to 0.23, or even less than or equal to 0.21. In embodiments, the Poisson's ratio of the glass-ceramic article may be greater than or equal to 0.17 and less than or equal to 0.23, greater than or equal to 0.17 and less than or equal to 0.21, greater than or equal to 0.19 and less than or equal to 0.23, or even greater than or equal to 0.19 and less than or equal to 0.21, or any and all subranges formed from any of these endpoints.

[0146] In embodiments, the SOC of the glass-ceramic article may be 2.5 nm / mm / MPa or more, or even 2.4 nm / mm / MPa or more. In embodiments, the SOC of the glass-ceramic article may be 2.8 nm / mm / MPa or less, or even 2.7 nm / mm / MPa or less. The SOC of the glass-ceramic article may be 2.4 nm / mm / MPa or more and 2.8 nm / mm / MPa or less, 2.4 nm / mm / MPa or more and 2.7 nm / mm / MPa or less, 2.5 nm / mm / MPa or more and 2.8 nm / mm / MPa or less, 2.5 nm / mm / MPa or more and 2.7 nm / mm / MPa or less, or any and all ranges formed from any of these endpoints.

[0147] In embodiments, the glass-ceramic articles described herein can be ion-exchanged to strengthen the article. In a typical ion-exchange process, smaller metal ions in a glass-ceramic article are replaced, or "exchanged," with larger metal ions of the same valence in a layer near the outer surface of the glass-ceramic article. The replacement of smaller ions with larger ions creates compressive stresses in the layer of the glass-ceramic article. In embodiments, the metal ions are monovalent metal ions (e.g., Li + , Na + , K + , etc.), and the ion exchange is carried out by immersing the glass-ceramic article in a bath containing a molten salt of at least one of the larger metal ions that are to be exchanged for the smaller metal ions in the glass-ceramic article. + , Tl + , Cu + Other monovalent ions, such as , may be exchanged for monovalent ions. Ion exchange processes used to strengthen glass-ceramic articles may include, but are not limited to, immersion in a single bath or multiple baths of the same or different composition with optional washing and / or slow cooling steps between immersions.

[0148] When exposed to the glass-ceramic article, the ion exchange solution (e.g., a KNO and / or NaNO molten salt bath, which may also contain LiNO), according to embodiments, may be at a temperature of 350° C. or more and 500° C. or less, 360° C. or more and 450° C. or less, 370° C. or more and 440° C. or less, 360° C. or more and 420° C. or more and 400° C. or less, 375° C. or more and 475° C. or more and 400° C. or less, 410° C. or more and 490° C. or more, 420° C. or more and 480° C. or more, 430° C. or more and 470° C. or more, or even 440° C. or more and 460° C. or less, or any and all subranges formed from any of these endpoints. In embodiments, the glass-ceramic article may be exposed to the ion exchange solution for a period of time of at least 2 hours and not more than 24 hours, at least 2 hours and not more than 12 hours, at least 2 hours and not more than 6 hours, at least 8 hours and not more than 24 hours, at least 6 hours and not more than 24 hours, at least 6 hours and not more than 12 hours, at least 8 hours and not more than 24 hours, and even at least 8 hours and not more than 12 hours, or any and all subranges formed from any of these endpoints.

[0149] The resulting compressive stress layer may have a depth (also referred to as "depth of compression" or "DOC") of 100 μm or more at the surface of the glass-ceramic article at an ion-exchange time of 2 hours. In embodiments, the glass-ceramic article may be ion-exchanged to achieve a compression depth of 10 μm or more, 20 μm or more, 30 μm or more, 40 μm or more, 50 μm or more, 60 μm or more, 70 μm or more, 80 μm or more, 90 μm or more, or even 100 μm or more. In embodiments, the glass-ceramic article has a thickness "t" and may be ion-exchanged to achieve a compression depth of 0.25t or more, 0.27t or more, or even 0.30t or more.

[0150] The occurrence of this surface compression layer is beneficial for better crack resistance and higher flexural strength compared to materials that are not ion-exchanged. The surface compression layer has a higher concentration of ions exchanged into the glass-ceramic article compared to the concentration of ions exchanged into the bulk of the glass-ceramic article (i.e., areas that do not include surface compression).

[0151] In embodiments, glass-ceramic articles produced from the precursor glass compositions described herein may have a surface compressive stress after ion-exchange strengthening of 80 MPa or more, 100 MPa or more, or even 250 MPa or more. In embodiments, the glass-ceramic articles may have a surface compressive stress after ion-exchange strengthening of 1 GPa or less, 750 MPa or less, or even 500 MPa or less. In embodiments, the glass-ceramic articles may have a surface compressive stress after ion-exchange strengthening of 80 MPa or more and 1 GPa or less, 80 MPa or more and 750 MPa or less, 80 MPa or more and 500 MPa or less, 100 MPa or more and 1 GPa or less, 100 MPa or more and 750 MPa or less, 100 MPa or more and 500 MPa or less, 250 MPa or more and 1 GPa or less, 250 MPa or more and 750 MPa or less, or even 250 MPa or more and 500 MPa or less, or any and all sub-ranges formed from any of these endpoints.

[0152] The inclusion of alkaline earth oxides and / or transition metal oxides in the precursor glass compositions as described herein may increase the maximum central tension of the resulting glass-ceramic article. In embodiments, glass-ceramic articles produced from the precursor glass compositions described herein may have a central tension after ion-exchange strengthening of 30 MPa or more, 50 MPa or more, or even 100 MPa or more. In embodiments, glass-ceramic articles produced from the precursor glass compositions described herein may have a central tension after ion-exchange strengthening of 250 MPa or less, 200 MPa or less, or even 175 MPa or less. In embodiments, glass-ceramic articles produced from the precursor glass compositions described herein may have a central tension after ion exchange strengthening of greater than or equal to 30 MPa and less than or equal to 250 MPa, greater than or equal to 30 MPa and less than or equal to 200 MPa, greater than or equal to 30 MPa and less than or equal to 175 MPa, greater than or equal to 50 MPa and less than or equal to 250 MPa, greater than or equal to 50 MPa and less than or equal to 200 MPa, greater than or equal to 50 MPa and less than or equal to 175 MPa, greater than or equal to 100 MPa and less than or equal to 250 MPa, greater than or equal to 100 MPa and less than or equal to 200 MPa, or even greater than or equal to 100 MPa and less than or equal to 175 MPa, or any and all ranges formed from any of these endpoints.

[0153] In embodiments, the glass-ceramic article may have a sodium ion penetration depth (also referred to as chemical depth) after ion exchange of 0.025t or more, 0.1t or more, or even 0.2t or more. In embodiments, the glass-ceramic article may have a sodium ion penetration depth of 0.28t or less, or even 0.25t or less. In embodiments, the glass-ceramic article may have a sodium ion penetration depth of 0.025t or more and 0.28t or less, 0.025t or more and 0.25t or less, 0.1t or more and 0.28t or less, 0.1t or more and 0.25t or more, 0.2t or more and 0.28t or less, or even 0.2t or more and 0.25t or less, or any and all ranges formed from any of these endpoints.

[0154] In embodiments, the glass-ceramic article may have a potassium ion penetration depth after ion exchange of greater than or equal to 0t and less than or equal to 0.01t.

[0155] In embodiments, a process for producing a glass-ceramic article includes heat treating a precursor glass article formed from a precursor glass composition in a furnace at one or more preselected temperatures for one or more preselected times to induce glass homogenization and crystallization (i.e., nucleation and growth) of one or more crystalline phases (e.g., having one or more compositions, amounts, morphologies, sizes, or size distributions, etc.). In embodiments, the heat treating may include (i) heating the precursor glass article in the furnace to a nucleation temperature at a rate of at least 1° C. / min and not more than 10° C. / min, (ii) maintaining the precursor glass article in the furnace at the nucleation temperature for a time of at least 0.1 hours and not more than 8 hours to produce a nucleated crystallizable glass, (iii) heating the nucleated crystallizable glass article in the furnace to a crystallization temperature at a rate of at least 1° C. / min and not more than 10° C. / min, (iv) maintaining the nucleated crystallizable glass article in the furnace at the crystallization temperature for a time of at least 0.1 hours and not more than 8 hours to produce a glass-ceramic article, and (v) cooling the glass-ceramic article to room temperature.

[0156] In embodiments, the nucleation temperature can be greater than or equal to 600° C. and less than or equal to 900° C. In embodiments, the nucleation temperature can be greater than or equal to 600° C., or even greater than or equal to 650° C. In embodiments, the nucleation temperature can be less than or equal to 900° C., or even less than or equal to 800° C. In embodiments, the nucleation temperature can be greater than or equal to 600° C. and less than or equal to 900° C., greater than or equal to 600° C. and less than or equal to 800° C., greater than or equal to 650° C. and less than or equal to 900° C., or even greater than or equal to 650° C. and less than or equal to 800° C., or any and all ranges formed from any of these endpoints.

[0157] In embodiments, the crystallization temperature may be greater than or equal to 700° C. and less than or equal to 1000° C. In embodiments, the crystallization temperature may be greater than or equal to 700° C., or even greater than or equal to 750° C. In embodiments, the crystallization temperature may be less than or equal to 1000° C., or even less than or equal to 900° C. In embodiments, the crystallization temperature may be greater than or equal to 700° C. and less than or equal to 1000° C., greater than or equal to 700° C. and less than or equal to 900° C., greater than or equal to 750° C. and less than or equal to 1000° C., or even greater than or equal to 750° C. and less than or equal to 900° C., or any and all ranges formed from any of these endpoints.

[0158] As used herein, heating rate, nucleation temperature, and crystallization temperature refer to the heating rate and temperature of the furnace in which the precursor glass composition or precursor glass article is heat treated.

[0159] The precursor glass composition, as well as the temperature-time profile of the heat treatment step of heating to and maintaining the temperature at the crystallization temperature, are judiciously designed to produce one or more of the following desired attributes: the crystalline phase of the glass-ceramic article, the ratio of the one or more primary crystalline phases and / or the one or more secondary crystalline phases and the residual glass phase, the crystalline phase population of the one or more primary crystalline phases and / or the one or more secondary crystalline phases and the residual glass phase, and the grain size or grain size distribution within the one or more primary crystalline phases and / or the one or more secondary crystalline phases, which in turn may affect the ultimate integrity, quality, color, and / or opacity of the resulting glass-ceramic article.

[0160] The glass-ceramic articles described herein include a crystalline phase and a residual glass phase. In embodiments, the crystalline phase may include lithium disilicate and petalite. Lithium disilicate Li2Si2O5 is an orthorhombic crystal based on corrugated plates of {Si2O5} tetrahedral arrangements. The crystals are typically plate-like or lath-like in shape with prominent cleavage planes. Petalite Li2O·Al2O3·8SiO2 is an orthorhombic crystal based on corrugated plates of {Si2O5} tetrahedral arrangements. 10Glass-ceramic articles based on lithium disilicate and petalite exhibit highly desirable mechanical properties, including high bulk strength and fracture toughness, due to a microstructure of randomly oriented interlocking crystals that cause cracks to propagate through the material in a tortuous path around these crystals.

[0161] In embodiments, the total amount of lithium disilicate and petalite in the crystalline phase, based on the total weight of the crystalline phase, may be 50% or more, 60% or more, or even 70% or more by weight. In embodiments, the total amount of lithium disilicate and petalite in the crystalline phase, based on the total weight of the crystalline phase, may be 99% or less, 90% or less, or even 85% or less by weight. In embodiments, the total amount of lithium disilicate and petalite in the crystalline phase, based on the total weight of the crystalline phase, may be 50% or more and 99% or less, 50% or more and 90% or less, 50% or more and 85% or less, 60% or more and 99% or less, 60% or more and 90% or less, 60% or more and 85% or less, 70% or more and 99% or less, 70% or more and 90% or less, or even 70% or more and 85% or less by weight, or any and all ranges formed from any of these endpoints.

[0162] In embodiments, the amount of lithium disilicate in the crystalline phase, based on the total weight of the crystalline phase, may be 20% by weight or more, or even 30% by weight or more. In embodiments, the amount of lithium disilicate in the crystalline phase, based on the total weight of the crystalline phase, may be 60% by weight or less, or even 50% by weight or less. In embodiments, the amount of lithium disilicate in the crystalline phase, based on the total weight of the crystalline phase, may be 20% by weight or more and 60% by weight or less, 20% by weight or more and 50% by weight or less, 30% by weight or more and 60% by weight or less, or even 30% by weight or more and 50% by weight or less, or any and all ranges formed from any of these endpoints.

[0163] In embodiments, the amount of petalite in the crystalline phase, based on the total weight of the crystalline phase, may be 20% by weight or more, or even 30% by weight or more. In embodiments, the amount of petalite in the crystalline phase, based on the total weight of the crystalline phase, may be 60% by weight or less, or even 50% by weight or less. In embodiments, the amount of petalite in the crystalline phase, based on the total weight of the crystalline phase, may be 20% by weight or more and 60% by weight or less, 20% by weight or more and 50% by weight or less, 30% by weight or more and 60% by weight or less, or even 30% by weight or more and 50% by weight or less, or any and all ranges formed from any of these endpoints.

[0164] In embodiments, the crystalline phases of the glass-ceramic article, in addition to lithium disilicate and petalite, may further include lithium metasilicate, β-quartz, cristobalite, or combinations thereof.

[0165] In embodiments, the size of the crystalline phase lithium disilicate and petalite particles may be limited (e.g., 100 nm or less) such that the glass-ceramic article is transparent or transparent haze. In embodiments, the crystalline phase lithium disilicate and petalite particles may have a size of 10 nm or more, 25 nm or more, or even 50 nm or more. In embodiments, the crystalline phase lithium disilicate and petalite particles may have a size of 100 nm or less, or even 75 nm or less. In embodiments, the crystalline phase lithium disilicate and petalite particles may have a size of 10 nm or more and 100 nm or less, 10 nm or more and 75 nm or less, 25 nm or more and 100 nm or less, 25 nm or more and 75 nm or less, 50 nm or more and 100 nm or less, or even 50 nm or more and 75 nm or less, or any and all subranges formed from any of these endpoints.

[0166] In embodiments, the crystalline phase lithium disilicate and petalite particles may have an aspect ratio of 2:1 or greater, 5:1 or greater, 10:1 or greater, 20:1 or greater, or 25:1 or greater.

[0167] In embodiments, the glass-ceramic article may comprise, by weight (i.e., by weight %) of the glass-ceramic article, 50% or more crystalline phase and 50% or less residual glass phase, 60% or more crystalline phase and 40% or less residual glass phase, 70% or more crystalline phase and 30% or less residual glass phase, 80% or more crystalline phase and 20% or less residual glass phase, or even 90% or more crystalline phase and 10% or less residual glass phase, or any and all subranges formed from any of these endpoints, as determined according to Rietveld analysis of an XRD spectrum.

[0168] The glass-ceramic article may be provided as a sheet, which may then be reshaped by pressing, blowing, bending, sagging, vacuum forming, or other means into a curved or bent piece of uniform thickness.

[0169] The glass-ceramic articles described herein may be used in a variety of applications, including, for example, cover glass or glass backplane applications in consumer or commercial electronic devices, including LCD and LED displays, computer monitors, and automated teller machines (ATMs); touch screen or touch sensor applications, for example, for portable electronic devices, including mobile phones, personal media players, watches, and tablet computers; integrated circuit applications, including, for example, semiconductor wafers; photovoltaic applications; architectural glass applications; automotive or vehicular glass applications; or commercial or household appliance applications. In embodiments, consumer electronic devices (e.g., smartphones, tablet computers, watches, personal computers, ultrabooks, televisions, and cameras), architectural glass, and / or automotive glass may comprise the glass-ceramic articles as described herein.

[0170] An exemplary electronic device incorporating any of the glass-ceramic articles disclosed herein is shown in Figures 1 and 2. In particular, Figures 1 and 2 show a consumer electronic device 100 comprising a housing 102 having a front surface 104, a back surface 106, and sides 108; electrical components (not shown) at least partially within or completely within the housing, including at least a controller, memory, and a display 110 at or adjacent to the front surface of the housing; and a cover substrate 112 at or over the front surface of the housing so as to cover the display. In an embodiment, at least a portion of at least one of the cover substrate 112 and the housing 102 may comprise any of the glass-ceramic articles disclosed herein. EXAMPLES

[0171] So that the various embodiments may be more readily understood, reference is made to the following examples, which are intended to illustrate various embodiments of the precursor glass compositions and glass-ceramic articles described herein.

[0172] Table 1 lists exemplary and comparative precursor glass compositions (mol %) as well as the liquidus temperatures of the precursor glass compositions. Table 2 lists the heat treatment schedules for obtaining exemplary and comparative glass-ceramic articles, and the respective properties of the glass-ceramic articles. Glass-ceramic articles were formed from exemplary precursor glass compositions 1-29 and comparative precursor glass compositions C1-C9 listed in Table 1.

[0173] [Table 1-1]

[0174] [Table 1-2]

[0175] [Table 1-3]

[0176]

Table 1-4

[0177]

Table 1-5

[0178]

Table 1-6

[0179]

Table 1-7

[0180]

Table 2-1

[0181]

Table 2-2

[0182]

Table 2-3

[0183]

Table 2-4

[0184]

Table 2-5

[0185]

Table 2-6

[0186] [Table 2-7]

[0187] [Table 2-8]

[0188] As shown by the exemplary precursor glass compositions in Table 1 and the glass-ceramic articles in Table 2, the glass-ceramic articles formed from the precursor glass compositions described herein may be transparent or transparent haze lithium disilicate and petalite glass-ceramic articles with improved fracture toughness and elastic modulus.

[0189] 3, glass-ceramic articles formed from exemplary precursor glass compositions 2, 3, 5, and 12, and comparative precursor glass composition C1, were exposed to a 100% NaNO ion exchange bath at a temperature of 470° C. As shown in FIG. 3, the inclusion of MgO (exemplary precursor glass composition 5 (E5)), CaO (exemplary precursor glass composition 2 (E2)), SrO (exemplary precursor glass composition 12 (E12)), and BaO (exemplary precursor glass composition 3 (E3)) in the precursor glass compositions increased the maximum central tension of the exemplary glass-ceramic articles compared to the maximum central tension of the comparative glass-ceramic article formed from comparative precursor glass composition C1, which did not include any alkaline earth or transition metal oxides.

[0190] 4, glass-ceramic articles formed from exemplary precursor glass composition 17 and comparative precursor glass composition C2 were exposed to a 100% NaNO ion exchange bath at a temperature of 470° C. As shown in FIG. 4, the inclusion of Y2O3 (exemplary precursor glass composition 17 (E17)) in the precursor glass composition increased the maximum central tension of the exemplary glass-ceramic article compared to the maximum central tension of the comparative glass-ceramic article formed from comparative precursor glass composition C2, which did not include Y2O3 or other transition metal oxides or alkaline earth oxides.

[0191] 5, glass-ceramic articles formed from exemplary precursor glass composition 29, as well as comparative precursor glass compositions C3 and C4, were exposed to a 100% NaNO ion exchange bath at a temperature of 470° C. As shown in FIG. 5, the inclusion of Ta2O5 (precursor glass composition 29 (E29)) in the precursor glass composition increased the maximum central tension of the exemplary glass-ceramic articles compared to the maximum central tension of the comparative glass-ceramic articles formed from comparative precursor glass compositions C3 and C4, which did not include Ta2O5 or other transition metal oxides or alkaline earth oxides.

[0192] As shown in Figures 3-5, the inclusion of alkaline earth oxides and / or transition metal oxides in the precursor glass compositions described herein results in glass-ceramic articles with increased maximum central tension for a given ion exchange process, as compared to glass-ceramic articles formed from precursor glass compositions that do not include either alkaline earth oxides or transition metal oxides.

[0193] Further, Figures 3-5 show that the inclusion of certain alkaline earth oxides and / or transition metal oxides in the precursor glass compositions described herein will result in a more rapid achievement of the target central tension. For example, as shown in Figure 3, the glass-ceramic article formed from precursor glass composition 5 achieved a central tension of 100 MPa after about 6 hours of ion exchange, whereas the other glass-ceramic articles took longer to achieve a central tension of 100 MPa. The glass-ceramic article containing alkaline earth oxides and / or transition metal oxides achieves the target central tension more quickly because it produces more stress per ion exchange (requiring less ion exchange time). The shorter ion exchange time provides the advantages of lower cost and less stress relaxation that may occur upon exposure to high temperatures. Thus, the precursor glass compositions described herein can be tailored to include certain alkaline earth oxides and / or transition metal oxides to achieve the target central tension in a relatively short period of time.

[0194] It will be apparent to those skilled in the art that various modifications and variations may be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Therefore, it is intended that this specification cover modifications and variations of the various embodiments described herein, provided such modifications and variations come within the scope of the appended claims and their equivalents.

[0195] Preferred embodiments of the present invention will be described below in detail.

[0196] EMBODIMENT 1 1. A glass-ceramic article comprising: 60 mol% or more and 72 mol% or less of SiO2; 2.5 mol% or more and 8 mol% or less of Al2O3; 17 mol% or more and 26 mol% or less of Li2O; 0.2 mol% or more and 4 mol% or less of ZrO2, and 0.5 mol% or more and 2 mol% or less P2O5, Including, The alkaline earth oxides + transition metal oxides are 0.1 mol % or more and 6 mol % or less, the alkaline earth oxides are the sum of CaO, MgO, SrO, and BaO, and the transition metal oxides are the sum of La2O3, Y2O3, Ta2O5, and GeO2, P2O5+ZrO2 is 1 mol% or more and 6 mol% or less, (SiO2+Al2O3) / (P2O5+ZrO2) is 12 mol% or more and 34 mol% or less, The glass-ceramic article has a crystalline phase comprising lithium disilicate and petalite, wherein the total amount of lithium disilicate and petalite is greater than 50 weight percent, based on the total weight of the crystalline phase.

[0197] EMBODIMENT 2 2. The glass-ceramic article of claim 1, wherein the glass-ceramic article comprises greater than or equal to 0.5 mol % and less than or equal to 4 mol % ZrO2.

[0198] EMBODIMENT 3 3. The glass-ceramic article of embodiment 1 or 2, wherein the alkaline earth oxides plus transition metal oxides is equal to or greater than 0.1 mol % and equal to or less than 5 mol %.

[0199] EMBODIMENT 4 4. The glass-ceramic article of any one of embodiments 1 to 3, wherein P2O5+ZrO2 is greater than or equal to 2 mol% and less than or equal to 5 mol%.

[0200] EMBODIMENT 5 5. The glass-ceramic article of any one of claims 1 to 4, wherein (SiO2+Al2O3) / (P2O5+ZrO2) is equal to or greater than 14 mol% and equal to or less than 32 mol%.

[0201] EMBODIMENT 6 6. The glass-ceramic article of any one of the preceding claims, wherein a molar ratio of Li2O to Al2O3 is greater than or equal to 2 and less than or equal to 12.

[0202] EMBODIMENT 7 7. The glass-ceramic article of embodiment 6, wherein a molar ratio of LiO to AlO is greater than or equal to 4 and less than or equal to 10.

[0203] EMBODIMENT 8 8. The glass-ceramic article of any one of the preceding claims, wherein a molar ratio of LiO to SiO is greater than or equal to 0.25 and less than or equal to 0.5.

[0204] EMBODIMENT 9 9. The glass-ceramic article of embodiment 8, wherein a molar ratio of LiO to SiO is greater than or equal to 0.25 and less than or equal to 0.4.

[0205] EMBODIMENT 10 10. The glass-ceramic article of any one of claims 1 to 9, wherein the glass-ceramic article comprises greater than or equal to 2.5 mol% and less than or equal to 6 mol% Al2O3.

[0206] EMBODIMENT 11 11. The glass-ceramic article of any one of claims 1 to 10, wherein the glass-ceramic article comprises greater than or equal to 18 mol% and less than or equal to 24 mol% LiO.

[0207] EMBODIMENT 12 12. The glass-ceramic article of any one of the preceding claims, wherein the glass-ceramic article comprises greater than or equal to 0.7 mol % and less than or equal to 1.75 mol % P2O5.

[0208] EMBODIMENT 13 13. The glass-ceramic article of any one of the preceding claims, wherein R2O is equal to or greater than 17 mol% and equal to or less than 30 mol%, R2O being the sum of Li2O, Na2O, and K2O.

[0209] EMBODIMENT 14 the glass-ceramic article comprising: 0 mol% or more and 6 mol% or less of Na2O, and 0 mol% or more and 6 mol% or less of K2O, 14. The glass-ceramic article of any one of the preceding claims, comprising:

[0210] EMBODIMENT 15 the glass-ceramic article comprising: 0 mol% or more and 8 mol% or less of CaO; 0 mol% or more and 8 mol% or less of MgO; 0 mol% or more and 8 mol% or less of SrO, and 0 mol% or more and 8 mol% or less of BaO; 15. The glass-ceramic article of any one of the preceding claims, comprising:

[0211] EMBODIMENT 16 the glass-ceramic article comprising: 0 mol% or more and 4 mol% or less of La2O3, 0 mol% or more and 6 mol% or less of Y2O3, 0 mol% or more and 3 mol% or less of Ta2O5, and 0 mol% or more and 2 mol% or less of GeO2; 16. The glass-ceramic article of any one of the preceding claims, comprising:

[0212] EMBODIMENT 17 17. The glass-ceramic article of any one of the preceding claims, wherein the glass-ceramic article comprises greater than or equal to 0 mol% and less than or equal to 8 mol% B2O3.

[0213] EMBODIMENT 18 18. The glass-ceramic article of any one of the preceding claims, wherein the glass-ceramic article comprises greater than or equal to 0 mol % and less than or equal to 10 mol % ZnO.

[0214] EMBODIMENT 19 19. The glass-ceramic article of any one of the preceding claims, wherein the crystalline phase lithium disilicate and petalite particles have a grain size of 10 nm or more and 100 nm or less.

[0215] EMBODIMENT 20 20. The glass-ceramic article of any one of the preceding claims, wherein the crystalline phase of the glass-ceramic article further comprises lithium metasilicate, β-quartz, cristobalite, or a combination thereof.

[0216] EMBODIMENT 21 21. The glass-ceramic article of any one of claims 1 to 20, wherein the glass-ceramic article has an average transmittance, measured at an article thickness of 0.8 mm, of greater than or equal to 50% and less than or equal to 95% over the wavelength range of 400 nm to 800 nm.

[0217] EMBODIMENT 22 The fracture toughness K of the glass-ceramic article measured by the chevron-notched small square bar method IC , but 1.0MPa m 1 / 2 22. The glass-ceramic article of any one of the preceding claims.

[0218] EMBODIMENT 23 23. The glass-ceramic article of any one of the preceding claims, wherein the glass-ceramic article has an elastic modulus of 90 GPa or greater.

[0219] EMBODIMENT 24 24. The glass-ceramic article of any one of claims 1 to 23, wherein the glass-ceramic article is chemically strengthened in an ion exchange bath at a temperature of 350°C or more and 500°C or less for a period of 2 hours or more and 24 hours or less to form an ion-exchanged glass-ceramic article.

[0220] EMBODIMENT 25 25. The glass-ceramic article of claim 24, wherein the ion exchange bath comprises KNO.

[0221] EMBODIMENT 26 26. The glass-ceramic article of embodiment 25, wherein the ion exchange bath further comprises NaNO.

[0222] EMBODIMENT 27 27. The glass-ceramic article of any one of claims 24 to 26, wherein the glass-ceramic article has a maximum central tension of 30 MPa or greater.

[0223] EMBODIMENT 28 28. The glass-ceramic article of any one of claims 24 to 27, wherein the glass-ceramic article has a surface compressive stress of 80 MPa or more.

[0224] EMBODIMENT 29 29. The glass-ceramic article of any one of claims 24 to 28, wherein the glass-ceramic article has a compression depth of 0.025t or greater.

[0225] EMBODIMENT 30 30. The glass-ceramic article of any one of claims 24 to 29, wherein the glass-ceramic article has a sodium ion penetration depth of greater than or equal to 0.025t and less than or equal to 0.28t.

[0226] EMBODIMENT 31 31. The glass-ceramic article of any one of claims 24 to 30, wherein the glass-ceramic article has a potassium ion penetration depth greater than or equal to 0t and less than or equal to 0.01t.

[0227] EMBODIMENT 32 1. A glass composition comprising: 60 mol% or more and 72 mol% or less of SiO2; 2.5 mol% or more and 8 mol% or less of Al2O3; 17 mol% or more and 26 mol% or less of Li2O; 1.5 mol% or more and 4 mol% or less of ZrO2, and 0.5 mol% or more and 2 mol% or less P2O5, Including, The alkaline earth oxides + transition metal oxides are 0.1 mol % or more and 6 mol % or less, the alkaline earth oxides are the sum of CaO, MgO, SrO, and BaO, and the transition metal oxides are the sum of La2O3, Y2O3, Ta2O5, and GeO2, A glass composition in which P2O5+ZrO2 is 1 mol % or more and 6 mol % or less.

[0228] EMBODIMENT 33 33. The glass composition of embodiment 32, wherein the alkaline earth oxides plus transition metal oxides is 0.1 mol % or more and 5 mol % or less.

[0229] EMBODIMENT 34 34. The glass composition according to embodiment 32 or 33, wherein P2O5+ZrO2 is ≧2 mol% and ≦5 mol%.

[0230] EMBODIMENT 35 35. The glass composition according to any one of embodiments 32 to 34, wherein a molar ratio of Li2O to Al2O3 is 2 or more and 12 or less.

[0231] EMBODIMENT 36 36. The glass composition of embodiment 35, wherein a molar ratio of Li2O to Al2O3 is 4 or more and 10 or less.

[0232] EMBODIMENT 37 37. The glass composition according to any one of embodiments 32 to 36, wherein a molar ratio of LiO to SiO is equal to or greater than 0.25 and equal to or less than 0.5.

[0233] EMBODIMENT 38 38. The glass composition of embodiment 37, wherein a molar ratio of Li2O to SiO2 is equal to or greater than 0.25 and equal to or less than 0.4.

[0234] EMBODIMENT 39 39. The glass composition of any one of claims 32 to 38, wherein the glass composition comprises 2.5 mol% or more and 6 mol% or less of Al2O3.

[0235] EMBODIMENT 40 40. The glass composition of any one of claims 32 to 39, wherein the glass composition comprises greater than or equal to 18 mol% and less than or equal to 24 mol% Li2O.

[0236] EMBODIMENT 41 41. The glass composition of any one of claims 32 to 40, wherein the glass composition comprises greater than or equal to 0.7 mol % and less than or equal to 1.75 mol % P2O5.

[0237] EMBODIMENT 42 42. The glass composition according to any one of embodiments 32 to 41, wherein R2O is equal to or greater than 17 mol % and equal to or less than 30 mol %, R2O being the sum of Li2O, Na2O, and K2O.

[0238] EMBODIMENT 43 The glass composition comprises: 0 mol% or more and 8 mol% or less of CaO; 0 mol% or more and 8 mol% or less of MgO; 0 mol% or more and 8 mol% or less of SrO, and 0 mol% or more and 8 mol% or less of BaO; 43. The glass composition of any one of claims 32 to 42, comprising:

[0239] EMBODIMENT 44 The glass composition comprises: 0 mol% or more and 4 mol% or less of La2O3, 0 mol% or more and 6 mol% or less of Y2O3, 0 mol% or more and 3 mol% or less of Ta2O5, and 0 mol% or more and 2 mol% or less of GeO2; 44. The glass composition of any one of claims 32 to 43, comprising:

[0240] EMBODIMENT 45 45. The glass composition of any one of claims 32 to 44, wherein the glass composition comprises ≧0 mol % and ≦8 mol % B2O3.

[0241] EMBODIMENT 46 46. ​​The glass composition of any one of claims 32 to 45, wherein the glass composition comprises greater than or equal to 0 mol % and less than or equal to 10 mol % ZnO.

[0242] EMBODIMENT 47 1. A method of forming a glass-ceramic article, comprising: heating the precursor glass article in a furnace to a nucleation temperature at a rate of at least 1° C. / min and not more than 10° C. / min, the precursor glass article comprising: 60 mol% or more and 72 mol% or less of SiO2; 2.5 mol% or more and 8 mol% or less of Al2O3; 17 mol% or more and 26 mol% or less of Li2O; 0.5 mol% or more and 4 mol% or less of ZrO2, and 0.5 mol% or more and 2 mol% or less P2O5, a precursor glass composition comprising: The alkaline earth oxides + transition metal oxides are 0.1 mol % or more and 6 mol % or less, the alkaline earth oxides are the sum of CaO, MgO, SrO, and BaO, and the transition metal oxides are the sum of La2O3, Y2O3, Ta2O5, and GeO2, P2O5+ZrO2 is 1 mol% or more and 6 mol% or less, (SiO2+Al2O3) / (P2O5+ZrO2) is 12 mol% or more and 34 mol% or less; maintaining the precursor glass article at the nucleation temperature in the furnace for a period of at least 0.1 hours and not more than 8 hours to produce a nucleated crystallizable glass article; heating the nucleated crystallizable glass article in the furnace to a crystallization temperature at a rate of at least 1° C. / min and at most 10° C. / min; maintaining the nucleated crystallizable glass article at the crystallization temperature in the furnace for a period of at least 0.1 hours and not more than 8 hours to produce the glass-ceramic article, the glass-ceramic article having a crystalline phase comprising lithium disilicate and petalite, the total amount of lithium disilicate and petalite being greater than 50 weight percent, based on the total weight of the crystalline phase; and cooling the glass-ceramic article to room temperature; The method includes:

[0243] EMBODIMENT 48 48. The method of claim 47, wherein the glass-ceramic article has an average transmittance of greater than or equal to 50% and less than or equal to 95% over the wavelength range from 400 nm to 800 nm, measured at an article thickness of 0.8 mm.

[0244] EMBODIMENT 49 The fracture toughness K of the glass-ceramic article measured by the chevron-notched small square bar method IC , but 1.0MPa m 1 / 2 The method according to embodiment 47 or 48, wherein

[0245] EMBODIMENT 50 50. The method of any one of claims 47 to 49, wherein the glass-ceramic article has an elastic modulus of 90 GPa or greater.

[0246] EMBODIMENT 51 51. The method of any one of claims 47 to 50, further comprising strengthening the glass-ceramic article in an ion exchange bath at a temperature of 350°C to 500°C for a period of 2 hours to 12 hours to form an ion-exchanged glass-ceramic article.

[0247] EMBODIMENT 52 52. The method of embodiment 51, wherein the ion exchange bath comprises KNO.

[0248] EMBODIMENT 53 53. The method of embodiment 52, wherein the ion exchange bath further comprises NaNO.

[0249] EMBODIMENT 54 54. The method of any one of claims 51 to 53, wherein the glass-ceramic article has a maximum central tension of 30 MPa or greater.

[0250] EMBODIMENT 55 55. The method of any one of claims 51 to 54, wherein the glass-ceramic article has a surface compressive stress of 80 MPa or more.

[0251] EMBODIMENT 56 56. The method of any one of claims 51 to 55, wherein the glass-ceramic article has a compression depth of 0.025t or greater.

[0252] EMBODIMENT 57 57. The method of any one of claims 51 to 56, wherein the glass-ceramic article has a sodium ion penetration depth of greater than or equal to 0.025t and less than or equal to 0.28t.

[0253] EMBODIMENT 58 58. The method of any one of claims 51 to 57, wherein the glass-ceramic article has a potassium ion penetration depth greater than or equal to 0t and less than or equal to 0.01t.

[0254] EMBODIMENT 59 In consumer electronics, a housing having a front, a back, and sides; Electrical components disposed at least partially within said housing, the electrical components including at least a controller, a memory, and a display disposed on or adjacent a front surface of the housing; and 2. The glass-ceramic article of embodiment 1, wherein the glass-ceramic article is disposed over the display and / or forms part of the housing. Electronic devices, including [Explanation of symbols]

[0255] 100 Consumer Electronics 102 Case 104 Front 106 Back 108 Side 110 Display 112 Cover board

Claims

1. A glass-ceramic article, containing 60 mol% or more and 72 mol% or less of SiO ２ , 2.5 mol% or more and 8 mol% or less of Al ２ O ３ , 17 mol% or more and 26 mol% or less of Li ２ O, 0.2 mol% or more and 4 mol% or less of ZrO ２ , and 0.5 mol% or more and 2 mol% or less of P ２ O ５ , comprising the alkaline earth oxide + transition metal oxide is 0.1 mol% or more and 6 mol% or less, the alkaline earth oxide is the sum of CaO, MgO, SrO, and BaO, and the transition metal oxide is La ２ O ３ , Y ２ O ３ , Ta ２ O ５ , and GeO ２ in total, P ２ O ５ + ZrO ２ is 1 mol% or more and 6 mol% or less, (SiO ２ + Al ２ O ３ ) / (P ２ O ５ + ZrO ２ ) is 12 mol% or more and 34 mol% or less, the glass-ceramic article has a crystal phase containing lithium disilicate and cordierite, and the total amount of lithium disilicate and cordierite is more than 50% by mass based on the total mass of the crystal phase. A glass-ceramic article.

2. The glass-ceramic article according to claim 1, wherein the glass-ceramic article contains 0.5 mol% or more and 4 mol% or less of ZrO ２ .

3. The glass-ceramic article according to claim 1 or 2, wherein the alkaline earth oxide + transition metal oxide is 0.1 mol% or more and 5 mol% or less.

4. P ２ O ５ +ZrO ２ is 2 mol% or more and 5 mol% or less, the glass-ceramic article according to claim 1.

5. (SiO ２ +Al ２ O ３ ) / (P ２ O ５ +ZrO ２ ) is 14 mol% or more and 32 mol% or less, the glass-ceramic article according to claim 1.

6. The average transmittance of the glass-ceramic article is 50% or more and 95% or less over a wavelength range of 400 nm to 800 nm, measured at an article thickness of 0.8 mm, the glass-ceramic article according to claim 1.

7. The fracture toughness K ＩＣ of the glass-ceramic article measured by the small-sized angular bar method with a chevron notch is 1.0 MPa·m １／２ or more, the glass-ceramic article according to claim 1.

8. In a method for forming a glass-ceramic article, A step of heating a precursor glass article to a nucleation temperature in a furnace at a rate of 1 °C / min or more and 10 °C / min or less, wherein the precursor glass article is 60 mol% or more and 72 mol% or less of SiO ２ , 2.5 mol% or more and 8 mol% or less of Al ２ O ３ , 17 mol% or more and 26 mol% or less of Li ２ O, 0.5 mol% or more and 4 mol% or less of ZrO ２ , and 0.5 mol% or more and 2 mol% or less of P ２ O ５, made from a precursor glass composition containing the alkaline earth oxide + transition metal oxide is 0.1 mol% or more and 6 mol% or less, the alkaline earth oxide is the total of CaO, MgO, SrO, and BaO, and the transition metal oxide is La ２ O ３ , Y ２ O ３ , Ta ２ O ５ , and the total of GeO ２ , P ２ O ５ + ZrO ２ is 1 mol% or more and 6 mol% or less, (SiO ２ + Al ２ O ３ ) / (P ２ O ５ + ZrO ２ ) is 12 mol% or more and 34 mol% or less, a process, maintaining the precursor glass article at the nucleation temperature in the furnace for a period of 0.1 hour or more and 8 hours or less to produce a crystallizable glass article that has been nucleated, heating the crystallizable glass article that has been nucleated in the furnace to the crystallization temperature at a rate of 1 °C / min or more and 10 °C / min or less, maintaining the crystallizable glass article that has been nucleated in the furnace at the crystallization temperature for a period of 0.1 hour or more and 8 hours or less to produce the glass-ceramic article, the glass-ceramic article having a crystal phase containing lithium disilicate and cordierite, and the total amount of lithium disilicate and cordierite being more than 50% by mass based on the total mass of the crystal phase, a process, and cooling the glass-ceramic article to room temperature, A method comprising.

9. The method according to claim 8, further comprising a step of strengthening the glass-ceramic article in an ion-exchange bath at a temperature of 350 °C or more and 500 °C or less for a period of 2 hours or more and 12 hours or less to form an ion-exchanged glass-ceramic article.

10. The method according to claim 9, wherein the glass-ceramic article has a maximum central tension of 30 MPa or more.

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