High-strength glass ceramic having a petalite and lithium silicate structure

Abstract

A transparent or translucent glass-ceramic material is provided that has rapid ion exchangeability and high fracture toughness. [Solution] about 55 wt% to about 80 wt% SiO2; about 5 wt% to about 20 wt% Al2O3; about 5 wt. % to about 20 wt. % Li2O; about 2% to about 4% by weight of P2O5; and A precursor glass comprising about 0.2 wt. % to about 15 wt. % ZrO2.

Description

Cross - Reference to Related Applications

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 to U.S. Provisional Patent Application No. 62 / 061,385, filed Oct. 8, 2014, and U.S. Provisional Patent Application No. 62 / 205,120, filed Aug. 14, 2015, the contents of each of which are relied upon and incorporated herein by reference in their entirety.

Technical Field

[0002] Embodiments relate to glass and glass - ceramic compositions, and more particularly to high - strength glass - ceramic compositions having a combination of a petalite phase and a lithium silicate phase.

Background Art

[0003] Lithium disilicate glass - ceramics of the SiO2 - Li2O - K2O - ZnO - P2O5 - Al2O3 - ZrO2 system have been developed and sold for use as dental crowns, bridges, and overlays. The microstructure of interconnected tabular crystals of the glass - ceramic provides high mechanical strength, fracture toughness, and excellent chemical resistance. Compositions in this field were invented at Corning Incorporated and patented as Patent Document 1 (the "’799 Patent") by Beall et al.

[0004] Furthermore, known glass - based materials often exhibit inherent brittleness or low resistance to crack propagation. For example, due to their inherently low fracture toughness (e.g., 0.5 - 1.0 MPa·m 1 / 2 ) for oxide glasses and glass - ceramics, oxide glasses are sensitive to small defects and scratches. As a comparison point, commercially available single - crystal substrates have a fracture toughness of about 2.4 - about 4.5 MPa·m 1 / 2Shows the fracture toughness value. For example, chemical strengthening by an ion exchange process imparts a compressive stress layer to glass or glass ceramic from the surface to a certain depth (e.g., 50 to 100 μm), providing a certain degree of resistance to crack penetration on the surface of the glass or glass ceramic. However, the crack penetration resistance may be limited and becomes ineffective after the crack penetrates through the compressive stress layer into the volume of the glass or glass ceramic. Although the above strengthening provides a certain degree of resistance to crack penetration, the inherent properties (k1c) of the material are not affected by ion exchange. Particular focus has continued to be placed on improving the mechanical properties of glass-based materials, particularly with regard to damage resistance and fracture toughness. Therefore, it is necessary to provide materials with improved damage resistance and fracture toughness.

[0005] Ion-exchangeable lithium-containing aluminosilicate glass ceramic articles of the β-spodumene type are known, and these provide damage resistance and fracture toughness. However, β-spodumene-based glass ceramics are generally opaque, which thereby imposes constraints on the glass ceramic for display-related applications or other applications that require transparency or translucency. Therefore, there is a need for transparent or translucent glass ceramic materials that have rapid ion-exchangeability and high fracture toughness.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Summary of the Invention

Means for Solving the Problems

[0007] The first aspect includes a glass-ceramic article having a petalite crystalline phase and a lithium silicate crystalline phase, and the petalite crystalline phase and the lithium silicate crystalline phase have a higher weight percentage than other crystalline phases present in the glass-ceramic article. In some embodiments, the petalite crystalline phase constitutes 20-70 wt% of the glass-ceramic article, and the lithium silicate crystalline phase constitutes 20-60 wt% of the glass-ceramic article. In some embodiments, the petalite crystalline phase constitutes 45-70 wt% of the glass-ceramic article, and the lithium silicate crystalline phase constitutes 20-50 wt% of the glass-ceramic article. In some embodiments, the petalite crystalline phase constitutes 40-60 wt% of the glass-ceramic article, and the lithium silicate crystalline phase constitutes 20-50 wt% of the glass-ceramic article.

[0008] In some embodiments, the glass-ceramic article is transparent. In some embodiments, the glass-ceramic article has a transmittance of at least 85% for light in the wavelength range of 400 nm to 1000 nm. In some embodiments, the glass-ceramic article has a transmittance of at least 90% for light in the wavelength range of 400 nm to 1000 nm. In some embodiments, the glass-ceramic article is transparent. In some embodiments, the glass-ceramic article contains particles having a longest dimension of 500 nm or less or 100 nm or less.

[0009] In some embodiments, the glass-ceramic article has a composition containing the following by weight%: SiO2: 55-80%; Al2O3: 2-20%; Li2O: 5-20%; B2O3: 0-10%; Na2O: 0-5%; ZnO: 0-10%; P2O5: 0.5-6%; and ZrO2: 0.2-15%.

[0010] In some embodiments, the glass ceramic article has a composition further comprising any of the following additional components by weight%: K2O: 0 - 4%; MgO: 0 - 8%; TiO2: 0 - 5%; CeO2: 0 - 0.4%; and SnO2: 0.05 - 0.5%.

[0011] In some embodiments, the glass ceramic article has a composition comprising the following by weight%: SiO2: 69 - 80%; Al2O3: 6 - 9%; Li2O: 10 - 14%; B2O3: 0 - 2%; P2O5: 1.5 - 2.5%; and ZrO2: 2 - 4%.

[0012] In some embodiments, the glass ceramic article has a composition comprising the following by weight%: SiO2: 69 - 80%; Al2O3: 6 - 9%; Li2O: 10 - 14%; Na2O: 1 - 2%; K2O: 1 - 2%; B2O3: 0 - 12%; P2O5: 1.5 - 2.5%; and ZrO2: 2 - 4%.

[0013] In some embodiments, the glass ceramic article has a composition comprising the following by weight%: SiO2: 65 - 80%; Al2O3: 5 - 16%; Li2O: 8 - 15%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 2%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 6%.

[0014] In some embodiments, the glass ceramic article has a composition comprising, in weight %: SiO2: 60 - 80%; Al2O3: 5 - 20%; Li2O: 5 - 20%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 4%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 8%.

[0015] In some embodiments, the sum of the weight percentages of P2O5 and ZrO2 in the glass ceramic composition is greater than 3.

[0016] In some embodiments, the glass ceramic article comprises one or more of the following: a fracture toughness of 1 MPa·m 1 / 2 or greater; a Vickers hardness of about 600 kgf / mm 2 (about 5884 N / mm 2 ) or greater; or a ring-on-ring strength of at least 300 MPa. In some embodiments, the glass ceramic article has a compression stress layer formed by ion exchange having a layer depth (depth of layer: DOL) of at least about 30 μm. In some embodiments, the ion-exchanged glass ceramic article is not brittle.

[0017] A second aspect includes a method of forming a glass ceramic article, the method comprising, in weight %: SiO2: 55 - 80%; Al2O3: 2 - 20%; Li2O: 5 - 20%; B2O3: 0 - 10%; Na2O: 0 - 5%; ZnO: 0 - 10%; P2O5: 0.5 - 6%; and ZrO2: 0.2 - 15% forming a glass composition comprising; and ceramming the glass composition to form a glass-ceramic article comprising a petalite crystalline phase and a lithium silicate crystalline phase comprising, the petalite crystalline phase and the lithium silicate crystalline phase have a higher weight percentage than other crystalline phases present in the glass-ceramic article.

[0018] In some embodiments, the method comprises forming a glass composition further comprising, in weight percentages: K2O: 0-4%; MgO: 0-8%; TiO2: 0-5%; CeO2: 0-0.4%; and SnO2: 0.05-0.5%.

[0019] In some embodiments, the method comprises forming a glass composition further comprising, in weight percentages: SiO2: 69-80%; Al2O3: 6-9%; Li2O: 10-14%; B2O3: 0-2%; P2O5: 1.5-2.5%; and ZrO2: 2-4%.

[0020] In some embodiments, the method comprises forming a glass composition further comprising, in weight percentages: SiO2: 69-80%; Al2O3: 6-9%; Li2O: 10-14%; Na2O: 1-2%; K2O: 1-2%; B2O3: 0-12%; P2O5: 1.5-2.5%; and ZrO2: 2-4%.

[0021] In some embodiments, the method includes forming a glass composition further comprising the following by weight percentage: SiO2: 65 - 80%; Al2O3: 5 - 16%; Li2O: 8 - 15%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 2%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 6%.

[0022] In some embodiments, the method includes forming a glass composition further comprising the following by weight percentage: SiO2: 60 - 80%; Al2O3: 5 - 20%; Li2O: 5 - 20%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 4%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 8%.

[0023] In some embodiments, the total weight percentage of P2O5 and ZrO2 in the above glass - ceramic composition is greater than 3.

[0024] In some embodiments, the method further includes ion - exchanging the above glass - ceramic article to produce a compressive stress layer having a layer depth of at least 30 μm. In some embodiments, the ion - exchanged glass - ceramic article is not brittle.

[0025] In some embodiments, the step of ceramizing comprises the following consecutive steps: heating the glass composition to a preliminary glass nucleation temperature; maintaining the preliminary glass nucleation temperature for a predetermined period; heating the composition to a nucleation temperature; maintaining the nucleation temperature for a predetermined period; heating the composition to a crystallization temperature; and maintaining the crystallization temperature for a predetermined period.

[0026] In some embodiments, the step of ceramizing comprises the following consecutive steps: heating the composition to a nucleation temperature; maintaining the nucleation temperature for a predetermined period; heating the composition to a crystallization temperature; and maintaining the crystallization temperature for a predetermined period.

[0027] In some embodiments, the method forms a glass-ceramic article, wherein the petalite crystalline phase constitutes 20-70 wt% of the glass-ceramic article, and the lithium silicate crystalline phase constitutes 20-60 wt% of the glass-ceramic article.

[0028] Other features and advantages of the present invention will become apparent by reading the following detailed description with reference to the accompanying drawings.

Brief Description of the Drawings

[0029]

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DETAILED DESCRIPTION OF THE INVENTION

[0030] In the following detailed description, numerous specific details may be set forth in order to provide a thorough understanding of the embodiments described herein. However, it will be apparent to one of ordinary skill in the art that embodiments may be practiced without some or all of these specific details. In other instances, well-known features or processes may not be described in detail so as not to obscure the present disclosure unnecessarily. Further, like or identical reference numbers may be used to identify common or similar elements. Additionally, unless otherwise defined, all technical and chemical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In case of a conflict in meaning, the present specification, including the definitions, will control.

[0031] Although other methods and materials can be used in the practice or testing of the embodiments, specific preferred methods and materials are described herein.

[0032] Disclosed are materials, compounds, compositions, and components that can be used with the methods and compositions of the present disclosure, can be used in the preparation of the methods and compositions of the present disclosure, or are embodiments of the methods and compositions of the present disclosure. Although these and other materials are disclosed herein and combinations, subsets, interactions, groups, etc. of these materials are disclosed, it should be understood that each of the various individual and collective combinations and permutations of these compounds may not be explicitly recited, yet each is specifically contemplated and described herein.

[0033] Accordingly, if substituents A, B, and C are disclosed along with classes D, E, and F of substituents and examples A-D of combination embodiments are disclosed, each is considered both individually and collectively. Thus, in this example, from the disclosure of A, B, and / or C; D, E, and / or F; and exemplary combination A-D, combinations A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are specifically contemplated and considered to be disclosed. Similarly, any subset or combination of these is specifically contemplated and disclosed. Thus, for example, from the disclosure of A, B, and / or C; D, E, and / or F; and exemplary combination A-D, subgroups A-E, B-F, and C-E are also specifically contemplated and considered to be disclosed. This concept applies to all aspects of the present disclosure, including but not limited to any components of the above compositions and steps of methods of making and using the compositions of the present disclosure. More specifically, exemplary compositional ranges recited herein are considered to be part of this specification, and further, the endpoints of exemplary numerical ranges are provided as being equivalent in every respect to those specifically included in the text, and all combinations are specifically contemplated and disclosed. Further, if there are various additional steps that are possible, it should be understood that each of these additional steps can be carried out with any specific embodiment or combination of embodiments of the method of the present disclosure, and each of the above combinations is specifically contemplated and considered to be disclosed.

[0034] Furthermore, when a range of numerical values including upper and lower limits is recited herein, unless expressly specified to the contrary in a particular context, the range is intended to include its endpoints and all integers and fractions within the range. When a range is defined, it is not intended to limit the scope of the present disclosure to the specific values recited. Further, when a quantity, concentration, or other value or parameter is given as a range, one or more preferred ranges, or a list of preferred upper and lower values, this is to be understood as specifically disclosing all ranges formed from any pair of any upper range limit or preferred value and any lower range limit or preferred value, whether or not such pairs are individually disclosed. Finally, when the term “about” is used in connection with the recitation of a value or endpoint of a range, the present disclosure is to be understood as including the recited specific value or endpoint.

[0035] As used herein, the term “about” means that the quantity, size, formulation, parameter, and other quantities and characteristics are not and need not be exact, but rather are approximate and / or may be, as appropriate, greater or less by tolerances, conversion factors, rounding, measurement errors, and other factors known to those of skill in the art. In general, the quantity, size, formulation, parameter, or other quantity or characteristic is “about” or “approximate” whether or not expressly so stated.

[0036] As used herein, the term “or” is inclusive; more specifically, the phrase “A or B” means “A, B, or both A and B.” Exclusive “or” is indicated herein, for example, by the terms “either A or B” and “one of A or B.”

[0037] The indefinite articles "a" and "an" are used to describe the elements and components of the present disclosure. The use of these articles means that one or at least one of these elements or components is present. These articles have conventionally been used to mean that the noun being modified is a singular noun, but as used herein, the articles "a" and "an" include the plural as well, unless specifically stated otherwise in a particular instance. Similarly, as used herein, the definite article "the" also means that the noun being modified can be singular or plural, unless specifically stated otherwise in a particular instance.

[0038] For purposes of describing embodiments, note that references herein to a variable being a "function" of a parameter or another variable are not intended to indicate that the variable is a function of only the parameter or variables recited. Rather, references to a variable that is a "function" of the recited parameter are intended to be non-limiting, and thus the variable can be a function of a single parameter or multiple parameters.

[0039] Note that terms such as "preferably," "commonly," and "typically" as used herein are not used to limit the scope of the present disclosure or to imply that a particular feature is decisive, essential, or more important to the structure or function of the present disclosure. Rather, these terms are merely intended to identify particular aspects of certain embodiments of the present disclosure or to highlight alternative or additional features that may or may not be used in a particular embodiment of the present disclosure.

[0040] One or more of the claims may use the term "wherein" as a transitional phrase. For the purpose of defining the present disclosure, this term is introduced into the claims as a non-limiting transitional phrase used to introduce a recitation of a series of features of a structure and should be construed in a manner similar to the more commonly used non-limiting preamble term "comprising".

[0041] Certain impurities or components that are not deliberately added, as a result of the raw materials and / or equipment used in manufacturing the glass or glass-ceramic composition of the present disclosure, may be present in the final glass or glass-ceramic composition. Such materials are present in trace amounts in the glass or glass-ceramic composition and are referred to herein as "tramp material".

[0042] As used herein, a glass or glass-ceramic composition having 0 wt% of a certain compound means that although the compound, molecule or element was not intentionally added to the composition, the composition may still contain the compound, typically in trace or small amounts. Similarly, "iron-free", "sodium-free", "lithium-free", "zirconium-free", "alkali earth metal-free", or "heavy metal-free", etc. are defined to mean that although the compound, molecule or element was not intentionally added to the composition, the composition may still contain iron, sodium, lithium, zirconium, alkali earth metal or heavy metal, etc., but only in approximately trace or small amounts.

[0043] Unless otherwise specified, the concentrations of all components described herein are expressed in weight percent (wt%).

[0044] Glass and Glass-Ceramics As described above, it is desirable to obtain a transparent or translucent lithium-containing aluminosilicate glass-ceramic composition having petalite and lithium silicate as primary crystal phases. The lithium silicate crystal phase may be lithium disilicate or lithium metasilicate. The improved properties of the glass and glass-ceramic compositions disclosed herein include the following: 1) The glass retains a low melting point (less than 1500 ° C) while providing a relatively high liquid-phase viscosity (> 2000 poise) and a wide processing range compatible with conventional rolling, forming, and float processes; 2) Lithium silicate is retained as the primary crystal phase, which provides the glass-ceramic with inherent high mechanical strength and fracture toughness; and 3) Petalite is the second primary crystal phase, has a fine particle size that contributes to the transparency or translucency of the glass-ceramic, and can be ion-exchanged for additional mechanical strength. Further, the above materials can be ceramized with minimal deformation into a certain shape, can be easily machined into an accurate shape, can be cut, drilled, chamfered, tapped, polished to an excellent gloss using conventional ceramic machining tools, and can exhibit various degrees of translucency depending on the composition and heat treatment. Due to these properties, the above glass-ceramic can be used in a wide variety of applications, such as counter tops and other surfaces; covers for consumer electronic devices of the hand-held type, desktop type, and wall-mounted type; doors and exteriors of household appliances; floor tiles; wall panels; ceiling panels; whiteboards; material storage containers (hollow wares) such as beverage bottles; food sales and storage containers; and mechanical parts that require light weight, good wear resistance, and accurate dimensions. The above glass-ceramic can be formed into three-dimensional articles using various methods due to its relatively low viscosity.

[0045] Petalite, i.e., LiAlSi4O 10It is monoclinic and has a three-dimensional skeletal structure with a layered structure having folded Si2O5 layers connected by tetrahedra of Li and Al. Inorganic petalite is a lithium source and is used as a low thermal expansion phase to improve the thermal shock resistance of glass ceramics or ceramic parts. Furthermore, glass ceramic articles based on the petalite phase can be chemically strengthened in a salt bath, during which Na + (and / or K + ) replaces Li in the petalite structure +Replace it, which causes compression and strengthening of the surface. In some embodiments, the weight percentage of the petalite crystalline phase in the glass-ceramic composition is about 20 to about 70 wt%, about 20 to about 65 wt%, about 20 to about 60 wt%, about 20 to about 55 wt%, about 20 to about 50 wt%, about 20 to about 45 wt%, about 20 to about 40 wt%, about 20 to about 35 wt%, about 20 to about 30 wt%, about 20 to about 25 wt%, about 25 to about 70 wt%, about 25 to about 65 wt%, about 25 to about 60 wt%, about 25 to about 55 wt%, about 25 to about 50 wt%, about 25 to about 45 wt%, about 25 to about 40 wt%, about 25 to about 35 wt%, about 25 to about 30 wt%, about 30 to about 70 wt%, about 30 to about 65 wt%, about 30 to about 60 wt%, about 30 to about 55 wt%, about 30 to about 50 wt%, about 30 to about 45 wt%, about 30 to about 40 wt%, about 30 to about 35 wt%, about 35 to about 70 wt%, about 35 to about 65 wt%, about 35 to about 60 wt%, about 35 to about 55 wt%, about 35 to about 50 wt%, about 35 to about 45 wt%, about 35 to about 40 wt%, about 40 to about 70 wt%, about 40 to about 65 wt%, about 40 to about 60 wt%, about 40 to about 55 wt%, about 40 to about 50 wt%, about 40 to about 45 wt%, about 45 to about 70 wt%, about 45 to about 65 wt%, about 45 to about 60 wt%, about 45 to about 55 wt%, about 45 to about 50 wt%, about 50 to about 70 wt%, about 50 to about 65 wt%, about 50 to about 60 wt%, about 50 to about 55 wt%, about 55 to about 70 wt%, about 55 to about 65 wt%, about 55 to about 60 wt%, about 60 to about 70 wt%, about 60 to about 65 wt%, or about 65 to about 70 wt%. In some embodiments, the glass-ceramic has a petalite crystalline phase of about 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, or 70 wt%.

[0046] As described above, the lithium silicate crystalline phase may be lithium disilicate or lithium metasilicate. Lithium disilicate, i.e., Li2Si2O5, is an orthorhombic crystal based on a wavy sheet of {Si2O5} tetrahedral arrays. The crystals are typically plate-like or rod-like in shape and have prominent cleavage planes. Glass-ceramics based on lithium disilicate provide highly desirable mechanical properties, including high bulk strength and fracture toughness, due to their microstructure of randomly oriented interconnected crystals - i.e., a crystal structure that propagates cracks through the tortuous paths around these crystals. Lithium metasilicate, i.e., Li2SiO3, has orthorhombic symmetry, with (Si2O6) chains running parallel to the c-axis and being integrally linked by lithium ions. Lithium metasilicate crystals can be easily dissolved in hydrofluoric acid diluted from glass-ceramics. In some embodiments, the weight percentage of the lithium silicate crystalline phase in the glass-ceramic composition can be in the range of about 20 to about 60 wt%, about 20 to about 55 wt%, about 20 to about 50 wt%, about 20 to about 45 wt%, about 20 to about 40 wt%, about 20 to about 35 wt%, about 20 to about 30 wt%, about 20 to about 25 wt%, about 25 to about 60 wt%, about 25 to about 55 wt%, about 25 to about 50 wt%, about 25 to about 45 wt%, about 25 to about 40 wt%, about 25 to about 35 wt%, about 25 to about 30 wt%, about 30 to about 60 wt%, about 30 to about 55 wt%, about 30 to about 50 wt%, about 30 to about 45 wt%, about 30 to about 40 wt%, about 30 to about 35 wt%, about 35 to about 60 wt%, about 35 to about 55 wt%, about 35 to about 50 wt%, about 35 to about 45 wt%, about 35 to about 40 wt%, about 40 to about 60 wt%, about 40 to about 55 wt%, about 40 to about 50 wt%, about 40 to about 45 wt%, about 45 to about 60 wt%, about 45 to about 55 wt%, about 45 to about 50 wt%, about 50 to about 60 wt%, about 50 to about 55 wt%, or about 55 to about 60 wt%.In some embodiments, the glass ceramic has a lithium silicate crystalline phase of 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, or 60 wt%.

[0047] There are two broad families of lithium disilicate glass ceramics. The first group includes those doped with noble metals such as ceria and silver. These are capable of photosensitive nucleation by UV light and can then be heat treated to produce tough glass ceramics such as Fotoceram®. The second family of lithium disilicate glass ceramics is nucleated by the addition of P2O5, where the nucleating phase is Li3PO4. P2O5-nucleated lithium disilicate glass ceramics have been developed for a wide range of applications such as high-temperature sealing materials, disks for computer hard drives, transparent protective clothing, and dental applications.

[0048] The glasses and glass-ceramics described herein are often described generally as lithium-containing aluminosilicate glasses or glass-ceramics and contain SiO2, Al2O3, and Li2O. In addition to SiO2, Al2O3, and Li2O, the glasses and glass-ceramics described herein may further contain alkali salts such as Na2O, K2O, Rb2O, or Cs2O, as well as P2O5 and ZrO2, and a number of other components described below. In one or more embodiments, the major crystalline phases include petalite and lithium silicate, although β-spodumene ss, β-quartz ss, lithium phosphate, cristobalite, and rutile may also be present as minor phases depending on the composition of the precursor glass. In some embodiments, the glass-ceramic composition has a residual glass content of about 5 to about 30 wt%, about 5 to about 25 wt%, about 5 to about 20 wt%, about 5 to about 15 wt%, about 5 to about 10 wt%, about 10 to about 30 wt%, about 10 to about 25 wt%, about 10 to about 20 wt%, about 10 to about 15 wt%, about 15 to about 30 wt%, about 15 to about 25 wt%, about 15 to about 20 wt%, about 20 to about 30 wt%, about 20 to about 25 wt%, or about 25 to about 30 wt%. In some embodiments, the residual glass content can be 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 wt%.

[0049] SiO2, an oxide involved in glass formation, can function to stabilize the network structures of glass and glass ceramics. In some embodiments, the glass or glass ceramic composition contains about 55% to about 80% by weight of SiO2. In some embodiments, the glass or glass ceramic composition contains 69% to about 80% by weight of SiO2. In some embodiments, the glass or glass ceramic composition can contain about 55% to about 80%, about 55% to about 77%, about 55% to about 75%, about 55% to about 73%, 60% to about 80%, about 60% to about 77%, about 60% to about 75%, about 60% to about 73%, 65% to about 80%, about 65% to about 77%, about 65% to about 75%, about 65% to about 73%, 69% to about 80%, about 69% to about 77%, about 69% to about 75%, about 69% to about 73%, about 70% to about 80%, about 70% to about 77%, about 70% to about 75%, about 70% to about 73%, about 73% to about 80%, about 73% to about 77%, about 73% to about 75%, about 75% to about 80%, about 75% to about 77%, or about 77% to about 80% by weight of SiO2. In some embodiments, the glass or glass ceramic composition contains about 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80% by weight of SiO2.

[0050] Regarding viscosity and mechanical properties, the viscosity and mechanical properties are affected by the glass composition. In the above glass and glass ceramics, SiO2 acts as a primary glass-forming oxide for the precursor glass and can function to stabilize the network structures of the glass and glass ceramics. The concentration of SiO2 must be high enough so that a petalite crystal phase is formed when the precursor glass is heat-treated to convert it into a glass ceramic. Since the melting point of pure SiO2 or high-SiO2 glass is undesirably high, the melting point (200 poise temperature) can be controlled by limiting the amount of SiO2.

[0051] Al2O3 can also impart stability to the network and provide improved mechanical properties and chemical resistance. However, if the amount of Al2O3 is too high, the proportion of lithium silicate crystals can be reduced to such an extent that, in some cases, an interconnected structure cannot be formed. By adjusting the amount of Al2O3, the viscosity can be controlled. Furthermore, if the amount of Al2O3 is too high, the viscosity of the melt generally increases. In some embodiments, the glass or glass-ceramic composition can include from about 2 to about 20 wt% Al2O3. In some embodiments, the glass or glass-ceramic composition can include from about 6 to about 9 wt% Al2O3. In some embodiments, the glass or glass-ceramic composition can include from about 2 to about 20%, from about 2 to about 18 wt%, from about 2 to about 15 wt%, from about 2 to about 12 wt%, from about 2 to about 10 wt%, from about 2 to about 9 wt%, from about 2 to about 8 wt%, from about 2 to about 5 wt%, from about 5 to about 20%, from about 5 to about 18 wt%, from about 5 to about 15 wt%, from about 5 to about 12 wt%, from about 5 to about 10 wt%, from about 5 to about 9 wt%, from about 5 to about 8 wt%, from about 6 to about 20%, from about 6 to about 18 wt%, from about 6 to about 15 wt%, from about 6 to about 12 wt%, from about 6 to about 10 wt%, from about 6 to about 9 wt%, from about 8 to about 20%, from about 8 to about 18 wt%, from about 8 to about 15 wt%, from about 8 to about 12 wt%, from about 8 to about 10 wt%, from about 10 to about 20%, from about 10 to about 18 wt%, from about 10 to about 15 wt%, from about 10 to about 12 wt%, from about 12 to about 20%, from about 12 to about 18 wt%, or from about 12 to about 15 wt% Al2O3. In some embodiments, the glass or glass-ceramic composition can include about 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt% Al2O3.

[0052] In the glasses and glass-ceramics described herein, Li2O aids in the formation of both petalite crystal phase and lithium silicate crystal phase. In practice, it is desirable to have at least about 7 wt% Li2O in the above composition to obtain petalite and lithium silicate as the dominant crystal phases. Further, once the Li2O becomes too high - about 15 wt% - it has been found that the above composition becomes highly fluid. In some embodiments, the glass or glass-ceramic can contain from about 5 wt% to about 20 wt% Li2O. In other embodiments, the glass or glass-ceramic can contain from about 10 wt% to about 14 wt% Li2O. In some embodiments, the glass or glass-ceramic composition can contain from about 5 to about 20 wt%, from about 5 to about 18 wt%, from about 5 to about 16 wt%, from about 5 to about 14 wt%, from about 5 to about 12 wt%, from about 5 to about 10 wt%, from about 5 to about 8 wt%, from 7 to about 20 wt%, from about 7 to about 18 wt%, from about 7 to about 16 wt%, from about 7 to about 14 wt%, from about 7 to about 12 wt%, from about 7 to about 10 wt%, from 10 to about 20 wt%, from about 10 to about 18 wt%, from about 10 to about 16 wt%, from about 10 to about 14 wt%, from about 10 to about 12 wt%, from 12 to about 20 wt%, from about 12 to about 18 wt%, from about 12 to about 16 wt%, from about 12 to about 14 wt%, from 14 to about 20 wt%, from about 14 to about 18 wt%, from about 14 to about 16 wt%, from about 16 to about 20 wt%, from about 16 to about 18 wt%, or from about 18 to about 20 wt% Li2O. In some embodiments, the glass or glass-ceramic composition can contain about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt% Li2O.

[0053] As described above, Li2O is generally useful for forming the glass ceramics of the embodiments, while other alkali oxides tend to reduce glass ceramic formation and form aluminosilicate residual glass in the glass ceramics. More than about 5 wt% of Na2O or K2O, or a combination thereof, results in an undesirable amount of residual glass, which has been found to lead to deformation during crystallization and undesirable microstructures with respect to mechanical properties. By adapting the composition of the residual glass, the viscosity during crystallization can be controlled, deformation or undesirable thermal expansion can be minimized, or the properties of the microstructure can be controlled. Thus, generally, the compositions described herein have small amounts of non-lithium alkali oxides. In some embodiments, the glass or glass ceramic composition can comprise from about 0 to about 5 wt% of R2O, where R is one or more of the alkali cations Na and K. In some embodiments, the glass or glass ceramic composition can comprise from about 1 to about 3 wt% of R2O, where R is one or more of the alkali cations Na and K. In some embodiments, the glass or glass ceramic composition can comprise 0 to about 5 wt%, 0 to 4 wt%, 0 to 3 wt%, 0 to about 2 wt%, 0 to about 1 wt%, >0 to about 5 wt%, >0 to about 4 wt%, >0 to about 3 wt%, >0 to about 2 wt%, >0 to about 1 wt%, about 1 to about 5 wt%, about 1 to about 4 wt%, about 1 to about 3 wt%, about 1 to about 2 wt%, about 2 to about 5 wt%, about 2 to about 4 wt%, about 2 to about 3 wt%, about 3 to about 5 wt%, about 3 to about 4 wt%, or about 4 to about 5 wt% of Na2O or K2O, or a combination thereof. In some embodiments, the glass or glass ceramic composition can comprise about 0, >0, 1, 2, 3, 4, or 5 wt% of R2O.

[0054] The above glass and glass-ceramic compositions can include P2O5. P2O5 can function as a nucleating agent to produce bulk nucleation. If the concentration of P2O5 is too low, the precursor glass will crystallize, but it will only be from the surface inward at high temperatures (due to low viscosity), resulting in a fragile and possibly deformed object. However, if the P2O5 is too high, devitrification after cooling during the formation of the precursor glass can become difficult to control. Embodiments can include from >0 to about 6 wt% P2O5. Other embodiments can include from about 2 to about 4 wt% P2O5. Still other embodiments can include from about 1.5 to about 2.5 wt% P2O5.The composition of the embodiment can contain P2O5 in an amount of 0 to about 6 wt%, 0 to about 5.5 wt%, 0 to about 5 wt%, 0 to about 4.5 wt%, 0 to about 4 wt%, 0 to about 3.5 wt%, 0 to about 3 wt%, 0 to about 2.5 wt%, 0 to about 2 wt%, 0 to about 1.5 wt%, 0 to about 1 wt%, >0 to about 6 wt%, >0 to about 5.5 wt%, >0 to about 5 wt%, >0 to about 4.5 wt%, >0 to about 4 wt%, >0 to about 3.5 wt%, >0 to about 3 wt%, >0 to about 2.5 wt%, >0 to about 2 wt%, >0 to about 1.5 wt%, >0 to about 1 wt%, about 0.5 to about 6 wt%, about 0.5 to about 5.5 wt%, about 0.5 to about 5 wt%, about 0.5 to about 4.5 wt%, about 0.5 to about 4 wt%, about 0.5 to about 3.5 wt%, about 0.5 to about 3 wt%, about 0.5 to about 2.5 wt%, about 0.5 to about 2 wt%, about 0.5 to about 1.5 wt%, about 0.5 to about 1 wt%, about 1 to about 6 wt%, about 1 to about 5.5 wt%, about 1 to about 5 wt%, about 1 to about 4.5 wt%, about 1 to about 4 wt%, about 1 to about 3.5 wt%, about 1 to about 3 wt%, about 1 to about 2.5 wt%, about 1 to about 2 wt%, about 1 to about 1.5 wt%, about 1.5 to about 6 wt%, about 1.5 to about 5.5 wt%, about 1.5 to about 5 wt%, about 1.5 to about 4.5 wt%, about 1.5 to about 4 wt%, about 1.5 to about 3.5 wt%, about 1.5 to about 3 wt%, about 1.5 to about 2.5 wt%, about 1.5 to about 2 wt%, about 2 to about 6 wt%, about 2 to about 5.5 wt%, about 2 to about 5 wt%, about 2 to about 4.5 wt%, about 2 to about 4 wt%, about 2 to about 3.5 wt%, about 2 to about 3 wt%, about 2 to about 2.5 wt%, about 2.5 to about 6 wt%, about 2.5 to about 5.5 wt%, about 2.5 to about 5 wt%, about 2.5 to about 4.5 wt%, about 2.5 to about 4 wt%, about 2.5 to about 3.5 wt%, about 2.5 to about 3 wt%, about 3 to about 6 wt%, about 3 to about 5.5 wt%, about 3 to about 5 wt%, about 3 to about 4.5 wt%, about 3 to about 4 wt%, about 3 to about 3.5 wt%, about 3.5 to about 6 wt%, about 3.5 to about 5.5 wt%, about 3.5 to about 5 wt%, about 3.5 to about 4.5 wt%, about 3.5 to about 4 wt%, about 4 to about 6 wt%, about 4 to about 5.5 wt%, about 4 to about 5 wt%, about 4 to about 4.5 wt%, about 4.5 to about 6 wt%, about 4.5 to about 5.5 wt%, about 4.5 to about 5 wt%, about 5 to about 6 wt%, about 5 to about 5.5 wt%, or about 5.5 to about 6 wt%.In some embodiments, the glass or glass-ceramic composition can comprise from about 0, >0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, or 6 weight % P2O5.

[0055] In the glasses and glass-ceramics described herein, it has generally been found that ZrO2 can improve the stability of Li2O-Al2O3-SiO2-P2O5 glasses by significantly reducing devitrification of the forming glass and lowering the liquidus temperature. At concentrations above 8 wt%, ZrSiO4 can form a primary liquid phase at high temperatures, thereby significantly reducing the liquid-phase viscosity. When the glass contains more than 2 wt% ZrO2, a transparent glass can be formed. The addition of ZrO2 can also assist in reducing the betalite particle size, which aids in the formation of a transparent glass-ceramic. In some embodiments, the glass or glass-ceramic composition can include from about 0.2 to about 15 wt% ZrO2. In some embodiments, the glass or glass-ceramic composition can include from about 2 to about 4 wt% ZrO2. In some embodiments, the glass or glass-ceramic composition can include from about 0.2 to about 15 wt%, from about 0.2 to about 12 wt%, from about 0.2 to about 10 wt%, from about 0.2 to about 8 wt%, from about 0.2 to 6 wt%, from about 0.2 to about 4 wt%, from 0.5 to about 15 wt%, from about 0.5 to about 12 wt%, from about 0.5 to about 10 wt%, from about 0.5 to about 8 wt%, from about 0.5 to 6 wt%, from about 0.5 to about 4 wt%, from 1 to about 15 wt%, from about 1 to about 12 wt%, from about 1 to about 10 wt%, from about 1 to about 8 wt%, from about 1 to 6 wt%, from about 1 to about 4 wt%, from 2 to about 15 wt%, from about 2 to about 12 wt%, from about 2 to about 10 wt%, from about 2 to about 8 wt%, from about 2 to 6 wt%, from about 2 to about 4 wt%, from about 3 to about 15 wt%, from about 3 to about 12 wt%, from about 3 to about 10 wt%, from about 3 to about 8 wt%, from about 3 to 6 wt%, from about 3 to about 4 wt%, from about 4 to about 15 wt%, from about 4 to about 12 wt%, from about 4 to about 10 wt%, from about 4 to about 8 wt%, from about 4 to 6 wt%, from about 8 to about 15 wt%, from about 8 to about 12 wt%, from about 8 to about 10 wt%, from about 10 to about 15 wt%, from about 10 to about 12 wt%, or from about 12 to about 15 wt% ZrO2. In some embodiments, the glass or glass-ceramic composition can include about 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15 wt% ZrO2.

[0056] B2O3 contributes to giving the precursor glass a low melting point. Further, the addition of B2O3 to the precursor glass, and thus to the glass ceramic, aids in achieving a mutually interconnected fine crystal structure and can also improve the damage resistance of the glass ceramic. When the boron in the residual glass is not in a charge-balanced state with the alkali oxide or divalent cation oxide, the boron is in a trigonal coordination state (i.e., three-coordinate boron), which opens up the structure of the glass. The network around these three-coordinate borons is not as rigid as that around tetrahedral coordination state (i.e., four-coordinate) borons. Without being bound by theory, it is considered that the precursor glass and glass ceramic containing three-coordinate boron can withstand a certain degree of deformation before cracks are formed. By withstanding a certain degree of deformation, the Vickers indenter crack initiation value increases. The fracture toughness of the precursor glass and glass ceramic containing three-coordinate boron can also increase. Without being bound by theory, the presence of boron in the residual glass (and precursor glass) of the glass ceramic causes the viscosity of the residual glass (or precursor glass) to decrease, which is considered to promote the growth of lithium silicate crystals, particularly large crystals with a high aspect ratio. It is considered that when the amount of three-coordinate boron increases (relative to four-coordinate boron), a glass ceramic showing a higher Vickers indenter crack initiation load can be obtained. In some embodiments, the amount of three-coordinate boron (as a percentage of the total B2O3) can be about 40% or more, 50% or more, 75% or more, about 85% or more, or even 95% or more. Generally, the amount of boron must be controlled to maintain the chemical resistance and mechanical strength of the ceramized bulk glass ceramic.

[0057] In one or more embodiments, the glasses and glass-ceramics described herein can include from 0 to about 10 wt% or from 0 to about 2 wt% B2O3. In some embodiments, the glass or glass-ceramic composition can include from 0 to about 10 wt%, from 0 to about 9 wt%, from 0 to about 8 wt%, from 0 to about 7 wt%, from 0 to about 6 wt%, from 0 to about 5 wt%, from 0 to about 4 wt%, from 0 to about 3 wt%, from 0 to about 2 wt%, from 0 to about 1 wt%, >0 to about 10 wt%, >0 to about 9 wt%, >0 to about 8 wt%, >0 to about 7 wt%, >0 to about 6 wt%, >0 to about 5 wt%, >0 to about 4 wt%, >0 to about 3 wt%, >0 to about 2 wt%, >0 to about 1 wt%, from about 1 to about 10 wt%, from about 1 to about 8 wt%, from about 1 to about 6 wt%, from about 1 to about 5 wt%, from about 1 to about 4 wt%, from about 1 to about 2 wt%, from about 2 to about 10 wt%, from about 2 to about 8 wt%, from about 2 to about 6 wt%, from about 2 to about 4 wt%, from about 3 to about 10 wt%, from about 3 to about 8 wt%, from about 3 to about 6 wt%, from about 3 to about 4 wt%, from about 4 to about 5 wt%, from about 5 wt% to about 8 wt%, from about 5 wt% to about 7.5 wt%, from about 5 wt% to about 6 wt%, or from about 5 wt% to about 5.5 wt% B2O3. In some embodiments, the glass or glass-ceramic composition can include about 0, >0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wt% B2O3.

[0058] MgO can enter into petalite crystals in a partial solid solution. In one or more embodiments, the glasses and glass-ceramics described herein can include from 0 to about 8 wt% MgO. In some embodiments, the glass or glass-ceramic composition can include from 0 to about 8 wt%, from 0 to about 7 wt%, from 0 to about 6 wt%, from 0 to about 5 wt%, from 0 to about 4 wt%, from 0 to about 3 wt%, from 0 to about 2 wt%, from 0 to about 1 wt%, from about 1 to about 8 wt%, from about 1 to about 7 wt%, from about 1 to about 6 wt%, from about 1 to about 5 wt%, from about 1 to about 4 wt%, from about 1 to about 3 wt%, from about 1 to about 2 wt%, from about 2 to about 8 wt%, from about 2 to about 7 wt%, from about 2 to about 6 wt%, from about 2 to about 5 wt%, from about 2 to about 4 wt%, from about 2 to about 3 wt%, from about 3 to about 8 wt%, from about 3 to about 7 wt%, from about 3 to about 6 wt%, from about 3 to about 5 wt%, from about 3 to about 4 wt%, from about 4 to about 8 wt%, from about 4 to about 7 wt%, from about 4 to about 6 wt%, from about 4 to about 5 wt%, from about 5 to about 8 wt%, from about 5 to about 7 wt%, from about 5 to about 6 wt%, from about 6 to about 8 wt%, from about 6 to about 7 wt%, or from about 7 wt% to about 8 wt% MgO. In some embodiments, the glass or glass-ceramic composition can include about 0, >0, 1, 2, 3, 4, 5, 6, 7, or 8 wt% MgO.

[0059] ZnO can enter into petalite crystals in a partial solid solution. In one or more embodiments, the glasses and glass-ceramics described herein can include from 0 to about 10 wt% ZnO. In some embodiments, the glass or glass-ceramic composition can include from 0 to about 10 wt%, from 0 to about 9 wt%, from 0 to about 8 wt%, from 0 to about 7 wt%, from 0 to about 6 wt%, from 0 to about 5 wt%, from 0 to about 4 wt%, from 0 to about 3 wt%, from 0 to about 2 wt%, from 0 to about 1 wt%, from about 1 to about 10 wt%, from about 1 to about 9 wt%, from about 1 to about 8 wt%, from about 1 to about 7 wt%, from about 1 to about 6 wt%, from about 1 to about 5 wt%, from about 1 to about 4 wt%, from about 1 to about 3 wt%, from about 1 to about 2 wt%, from about 2 to about 10 wt%, from about 2 to about 9 wt%, from about 2 to about 8 wt%, from about 2 to about 7 wt%, from about 2 to about 6 wt%, from about 2 to about 5 wt%, from about 2 to about 4 wt%, from about 2 to about 3 wt%, from about 3 to about 10 wt%, from about 3 to about 9 wt%, from about 3 to about 8 wt%, from about 3 to about 7 wt%, from about 3 to about 6 wt%, from about 3 to about 5 wt%, from about 3 to about 4 wt%, from about 4 to about 10 wt%, from about 4 to about 9 wt%, from about 4 to about 8 wt%, from about 4 to about 7 wt%, from about 4 to about 6 wt%, from about 4 to about 5 wt%, from about 5 to about 10 wt%, from about 5 to about 9 wt%, from about 5 to about 8 wt%, from about 5 to about 7 wt%, from about 5 to about 6 wt%, from about 6 to about 10 wt%, from about 6 to about 9 wt%, from about 6 to about 8 wt%, from about 6 to about 7 wt%, from about 7 to about 10 wt%, from about 7 to about 9 wt%, from about 7 wt% to about 8 wt%, from about 8 to about 10 wt%, from about 8 to about 9 wt%, or from about 9 to about 10 wt% ZnO. In some embodiments, the glass or glass-ceramic composition can include about 0, >0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wt% ZnO.

[0060] In one or more embodiments, the glass and glass-ceramics described herein can contain from 0 to about 5 wt% TiO₂. In some embodiments, the glass or glass-ceramic composition can contain from 0 to about 5 wt%, from 0 to about 4 wt%, from 0 to about 3 wt%, from 0 to about 2 wt%, from 0 to about 1 wt%, from about 1 to about 5 wt%, from about 1 to about 4 wt%, from about 1 to about 3 wt%, from about 1 to about 2 wt%, from about 2 to about 5 wt%, from about 2 to about 4 wt%, from about 2 to about 3 wt%, from about 3 to about 5 wt%, from about 3 to about 4 wt%, or from about 4 to about 5 wt% TiO₂. In some embodiments, the glass or glass-ceramic composition can contain about 0, >0, 1, 2, 3, 4, or 5 wt% TiO₂.

[0061] In one or more embodiments, the glass and glass-ceramics described herein can contain from 0 to about 0.4 wt% CeO₂. In some embodiments, the glass or glass-ceramic composition can contain from 0 to about 0.4 wt%, from 0 to about 0.3 wt%, from 0 to about 0.2 wt%, from 0 to about 0.1 wt%, from about 0.1 to about 0.4 wt%, from about 1 to about 0.3 wt%, from about 1 to about 0.2 wt%, from about 0.2 to about 0.4 wt%, from about 0.2 to about 0.3 wt%, or from about 0.3 to about 0.4 wt% CeO₂. In some embodiments, the glass or glass-ceramic composition can contain about 0, >0, 0.1, 0.2, 0.3, or 0.4 wt% CeO₂.

[0062] In one or more embodiments, the glasses and glass-ceramics described herein can contain from 0 to about 0.5 wt% SnO2. In some embodiments, the glass or glass-ceramic composition can contain from 0 to about 0.5 wt%, from 0 to about 0.4 wt%, from 0 to about 0.3 wt%, from 0 to about 0.2 wt%, from 0 to about 0.1 wt%, from about 0.05 to about 0.5 wt%, from 0.05 to about 0.4 wt%, from 0.05 to about 0.3 wt%, from 0.05 to about 0.2 wt%, from 0.05 to about 0.1 wt%, from about 0.1 to about 0.5 wt%, from about 0.1 to about 0.4 wt%, from about 0.1 to about 0.3 wt%, from about 0.1 to about 0.2 wt%, from about 0.2 to about 0.5 wt%, from about 0.2 to about 0.4 wt%, from about 0.2 to about 0.3 wt%, from about 0.3 to about 0.5 wt%, from about 0.3 to about 0.4 wt%, or from about 0.4 to about 0.5 wt% SnO2. In some embodiments, the glass or glass-ceramic composition can contain about 0, >0, 0.05, 0.1, 0.2, 0.3, 0.4, or 0.5 wt% SnO2.

[0063] In some embodiments, the total weight percentage of P2O5 and ZrO2 in the glasses and glass-ceramics disclosed herein can be about 3 wt%, 4 wt%, or 5 wt% or more, thereby increasing nucleation. The increased nucleation can result in the formation of smaller particles.

[0064] In some embodiments, the glass ceramic exhibits transparency across the visible light range (i.e., the glass ceramic is transparent). In some embodiments, the transparency of the glass ceramic can be achieved by generating crystals with a size smaller than the wavelength of the interrogating wavelength of light and by matching the refractive index of the residual glass with the refractive index of petalite (1.51) and the refractive index of lithium disilicate (1.55). In some embodiments, the transparent glass ceramic with a thickness of 1 mm can have a light transmittance of ≥90% (including surface reflection loss) across a wavelength range of about 400 nm to about 1000 nm. In one or more embodiments, the average transmittance for a transparent glass ceramic article is about 85% or more, about 86% or more, about 87% or more, about 88% or more, about 89% or more, about 90% or more, about 91% or more, about 92% or more, about 93% or more (including surface reflection loss) of light across a wavelength range of about 400 nm to about 1000 nm for a glass ceramic article with a thickness of 1 mm. In other embodiments, the glass ceramic may be translucent across the visible light range. In some embodiments, the translucent glass ceramic can have an average transmittance in the range of about 20% to less than about 85% of light across a wavelength range of about 400 nm to about 1000 nm for a glass ceramic article with a thickness of 1 mm. In embodiments where the glass ceramic is translucent, the glass ceramic can be white.

[0065] In some embodiments, the size of the particles in the glass ceramic can affect transparency or translucency. In some embodiments, the particles of the transparent glass ceramic may have a longest dimension of less than about 100 nm. In some embodiments, the particles of the translucent glass ceramic may have a longest dimension in the range of about 100 nm to about 500 nm. In some embodiments, the particles of the transparent glass ceramic may have an aspect ratio of about 2 or more. In some embodiments, the particles of the translucent glass ceramic may have an aspect ratio of about 2 or less.

[0066] Certain impurities or components that are not deliberately added may be present in the final glass or glass-ceramic composition due to the raw materials and / or equipment used to produce the glass or glass-ceramic composition of the present disclosure. Such materials are present in trace amounts in the glass or glass-ceramic composition and are referred to herein as "contaminants."

[0067] As used herein, a glass or glass-ceramic composition having 0 wt% of a certain compound is defined to mean that, although the compound, molecule or element was not intentionally added to the composition, the composition may still contain the compound, typically in trace or minor amounts. Similarly, "iron-free," "sodium-free," "lithium-free," "zirconium-free," "alkali earth metal-free," or "heavy metal-free," etc. are defined to mean that, although the compound, molecule or element was not intentionally added to the composition, the composition may still contain iron, sodium, lithium, zirconium, alkali earth metals or heavy metals, etc., but only in approximately trace or minor amounts. Minor compounds that may be found in the glasses or glass-ceramics of the embodiments herein include, but are not limited to, Na2O, TiO2, MnO, ZnO, Nb2O5, MoO3, Ta2O5, WO3, ZrO2, Y2O3, La2O3, HfO2, CdO, SnO2, Fe2O3, CeO2, As2O3, Sb2O3, sulfur-based compounds such as sulfuric acid, halogens, or combinations thereof.

[0068] In some embodiments, an antibacterial component may be added to the glass or glass-ceramic composition. This is particularly advantageous since the glass-ceramics of the embodiments herein can be used in applications where exposure to harmful bacteria can occur, such as kitchen or dining counter tops. Antibacterial components that can be added to the glass or glass-ceramic include, but are not limited to, Ag, AgO, Cu, CuO, Cu2O, etc. In some embodiments, the concentration of the antibacterial component is maintained at a level of about 3, 2, 1, or 0.5, >0 wt%. In some embodiments, the antibacterial component is >0 to about 3 wt%. In some embodiments, the antibacterial component is >0 to about 1 wt%.

[0069] In some embodiments, the glass or glass-ceramic may further include a chemical fining agent. Such fining agents include, but are not limited to, SnO2, As2O3, Sb2O3, F, Cl, and Br. In some embodiments, the concentration of the chemical fining agent is maintained at a level of 3, 2, 1, or 0.5, >0 wt%. In some embodiments, the amount of the fining agent is >0 to about 3 wt%. Other transition metal oxides such as CeO2, Fe2O3, and MnO2 are also included as chemical fining agents. Since these oxides may introduce an undesirable color to the glass or glass-ceramic by visible light absorption in one or more final valence states in the glass, when the oxides are present, their concentration is typically maintained at a level of 0.5, 0.4, 0.3, 0.2, 0.1, or >0 wt%.

[0070] The glass or glass-ceramic may also contain SnO2, for example, as a result of Joule thermal melting using a tin oxide electrode by batching a tin-containing material such as SnO2, SnO, SnCO3, SnC2O2, etc., or by adding SnO2 as an agent for adjusting various physical, melting, coloring, or forming properties. The glass or glass-ceramic can contain 0 to about 3 wt%, 0 to about 2 wt%, 0 to about 1 wt%, 0 to 0.5 wt%, or 0 to 0.1 wt% of SnO2.

[0071] In some embodiments, the glass or glass-ceramic can be substantially free of Sb2O3, As2O3, or combinations thereof. For example, the glass or glass-ceramic can contain 0.05 weight percent or less of Sb2O3, As2O3, or combinations thereof, the glass or glass-ceramic can contain 0 weight percent of Sb2O3, As2O3, or combinations thereof, or the glass or glass-ceramic can be, for example, free of any intentionally added Sb2O3, As2O3, or combinations thereof.

[0072] Additional benefits can be provided by introducing additional components into the glass composition, or the additional components can further include contaminants typically found in commercially prepared glass. For example, by adding additional components, various physical, melting, and forming properties can be adjusted. According to some embodiments, the glass can also include contaminants (such as ZrO2) associated with the batch materials and / or introduced into the glass by the melting, fining, and / or forming facilities used in the manufacture of the glass. In some embodiments, the glass can include one or more compounds useful as ultraviolet radiation absorbers. In some embodiments, the glass can contain 3 weight percent or less of TiO2, MnO, ZnO, Nb2O5, MoO3, Ta2O5, WO3, ZrO2, Y2O3, La2O3, HfO2, CdO, Fe2O3, CeO2, or combinations thereof. In some embodiments, the glass can contain from 0 to about 3 weight percent, 0 to about 2 weight percent, 0 to about 1 weight percent, 0 to 0.5 weight percent, 0 to 0.1 weight percent, 0 to 0.05 weight percent, or 0 to 0.01 weight percent of TiO2, MnO, ZnO, Nb2O5, MoO3, Ta2O5, WO3, ZrO2, Y2O3, La2O3, HfO2, CdO, SnO2, Fe2O3, CeO2, As2O3, Sb2O3, or combinations thereof.

[0073] In some embodiments, the glass described herein can be fabricated into a sheet by processes including, but not limited to, slot draw, float, rolling, and other sheet forming processes known to those skilled in the art. Alternatively, the glass composition may be formed by a float or rolling process known in the art.

[0074] In some embodiments, the glass composition described herein may be adapted to a float type forming process by adjusting the liquid phase viscosity. In some embodiments, the glass composition can have a liquid phase viscosity of from about 1500 P (150 Pa·s) to about 3000 P (300 Pa·s). In some embodiments, the glass composition can have a liquid phase viscosity of about 1000, 1200, 1500, 2000, 2500, or 3000 P (about 100, 120, 150, 200, 250, or 300 Pa·s). In some embodiments, the glass is about 50×10 ‐7 / K or more, about 50×10 ‐7 / K or more, about 60×10 ‐7 / K or more, about 61×10 ‐7 / K or more, about 62×10 ‐7 / K or more, about 63×10 ‐7 / K or more, about 64×10 ‐7 / K or more, about 65×10 ‐7 / K or more, about 66×10 ‐7 / K or more, about 67×10 ‐7 / K or more, about 68×10 ‐7 / K or more, about 69×10 ‐7 / K or more, about 70×10 ‐7 / K or more, about 71×10 ‐7 / K or more, about 72×10 ‐7 / K or more, about 73×10 ‐7 / K or more, about 74×10 ‐7 / K or more, about 75×10 ‐7 / K or more, about 76×10 ‐7 / K or more, about 77×10 ‐7 / K or more, about 78×10 ‐7 / K or more, about 79×10 ‐7 / K or more, or about 80×10 ‐7It can have a coefficient of thermal expansion of / K or more.

[0075] Articles formed from the glasses and glass-ceramics described herein can be of any reasonable thickness for use. Glass sheet and / or glass-ceramic embodiments can have any thickness from about 0.8 mm to about 10 mm. Some embodiments have a thickness of about 6 mm or less, about 5 mm or less, about 3 mm or less, about 1.0 mm or less, about 750 μm or less, about 500 μm or less, or about 250 μm or less. Some glass or glass-ceramic sheet embodiments can have a thickness from about 200 μm to about 5 mm, from about 500 μm to about 5 mm, from about 200 μm to about 4 mm, from about 200 μm to about 2 mm, from about 400 μm to about 5 mm, or from about 400 μm to about 2 mm. In some embodiments, the thickness can be from about 3 mm to about 6 mm or from about 0.8 mm to about 3 mm.

[0076] In some embodiments, the glass-ceramic has an equibiaxial flexural strength of about 300 MPa or more, about 325 MPa or more, about 350 MPa or more, about 375 MPa or more, about 400 MPa or more, about 425 MPa or more, or about 450 MPa or more in a 1 mm thick glass-ceramic. The equibiaxial flexural strength can also be referred to as the Ring-on-Ring (RoR) strength, which is measured according to the procedure described in ASTM: C1499-05 with some modifications to the test apparatus and test conditions, as outlined in paragraph

[0027] of U.S. Patent Publication No. 2013 / 0045375 (incorporated herein by reference). When the glass-ceramic is first subjected to friction, typically using silicon carbide particles, the Abraded Ring-on-Ring (aRoR) strength can also be measured using the above-described procedure. Some embodiments also include chemically strengthenable glass-ceramics having a petalite phase that results in an increase in flexural strength. In such embodiments, the RoR strength can be about 500 MPa or more, about 550 MPa or more, about 600 MPa or more, about 650 MPa or more, about 700 MPa or more, about 750 MPa or more, or about 800 MPa or more.

[0077] Some embodiments of the glass-ceramic exhibit high fracture toughness and inherent damage resistance. As described above, some embodiments of the glass-ceramic include interconnected lithium silicate crystals, which result in high fracture toughness. The glass-ceramic of one or more embodiments may include boron, which may be present as three-coordinated boron in the residual glass phase of the glass-ceramic. In such embodiments, the three-coordinated boron is provided by including B2O3 in the precursor glass. The three-coordinated boron provides a densification mechanism when the glass or glass-ceramic is subjected to a piezometric load.

[0078] In one or more embodiments, the glass-ceramic has a fracture toughness of about 1.0 MPa·m 1 / 2 or more, about 1.1 MPa·m 1 / 2 or more, 1.2 MPa·m 1 / 2 or more, 1.3 MPa·m 1 / 2 or more, 1.4 MPa·m 1 / 2 or more, 1.5 MPa·m 1 / 2 or more, 1.6 MPa·m 1 / 2 or more, 1.7 MPa·m 1 / 2 or more, 1.8 MPa·m 1 / 2 or more, 1.9 MPa·m 1 / 2 or more, or 2.0 MPa·m 1 / 2 and exhibits a fracture toughness of about 1 to about 2 MPa·m 1 / 2 In some embodiments, the fracture toughness is in the range of about 1 to about 2 MPa·m. The fracture toughness may be measured using methods known in the art, for example, using a chevron notched specimen in accordance with ASTM C1421-10, "Standard Test Method for Determination of Fracture Toughness of Fine Ceramics at Ambient Temperature".

[0079] In one or more embodiments, the glass-ceramic has high crack and scratch resistance by exhibiting a certain Vickers hardness. In some embodiments, the non-ion-exchanged glass-ceramic has a Vickers hardness of about 600 to about 900 kgf / mm 2 (about 5884 to about 8826 N / mm 2 ), about 600 to about 875 kgf / mm 2 (about 5884 to about 8581 N / mm 2) from approximately 600 to approximately 850 kgf / mm 2 (from approximately 5884 to approximately 8335 N / mm 2 ) from approximately 600 to approximately 825 kgf / mm 2 (from approximately 5884 to approximately 8090 N / mm 2 ) from approximately 600 to approximately 800 kgf / mm 2 (from approximately 5884 to approximately 7845 N / mm 2 ) from approximately 600 to approximately 775 kgf / mm 2 (from approximately 5884 to approximately 7600 N / mm 2 ) from approximately 600 to approximately 750 kgf / mm 2 (from approximately 5884 to approximately 7355 N / mm 2 ) from approximately 600 to approximately 725 kgf / mm 2 (from approximately 5884 to approximately 7110 N / mm 2 ) from approximately 600 to approximately 700 kgf / mm 2 (from approximately 5884 to approximately 6865 N / mm 2 ) from approximately 700 to approximately 900 kgf / mm 2 (from approximately 6865 to approximately 8826 N / mm 2 ) from approximately 700 to approximately 875 kgf / mm 2 (from approximately 6865 to approximately 8581 N / mm 2 ) from approximately 700 to approximately 850 kgf / mm 2 (from approximately 6865 to approximately 8335 N / mm 2 ) from approximately 700 to approximately 825 kgf / mm 2 (from approximately 6865 to approximately 8090 N / mm 2 ) or from approximately 700 to approximately 800 kgf / mm 2 (from approximately 6865 to approximately 7845 N / mm 2 ) represents the Vickers hardness. In some embodiments, the Vickers hardness is 600 kgf / mm 2 (approximately 5884 N / mm 2 ) or more, 625 kgf / mm 2 (approximately 6129 N / mm 2 ) or more, 650 kgf / mm 2 (approximately 6374 N / mm 2 ) or more, 675 kgf / mm 2 (approximately 6619 N / mm 2 ) or more, 700 kgf / mm 2 (approximately 6865 N / mm 2 ) or more, 725 kgf / mm2 (about 7110 N / mm 2 ) or more, 750 kgf / mm 2 (about 7355 N / mm 2 ) or more, 775 kgf / mm 2 (about 7600 N / mm 2 ) or more, 800 kgf / mm 2 (about 7845 N / mm 2 ) or more, 825 kgf / mm 2 (about 8090 N / mm 2 ) or more, 850 kgf / mm 2 (about 8335 N / mm 2 ) or more, 875 kgf / mm 2 (about 8581 N / mm 2 ) or more, or 900 kgf / mm 2 (about 8826 N / mm 2 ) or more. The Vickers hardness may be measured using ASTM C1326 and C1327 (and their dependencies; all of which are hereby incorporated by reference into this application), "Standard Test Method for Vickers Indentation Hardness of Fine Ceramics" (ASTM International, Conshohocken, Pennsylvania, USA). In some embodiments, the glass ceramic exhibits such a Vickers indenter crack initiation load value after chemical strengthening by ion exchange.

[0080] In some embodiments, the glass ceramic disclosed herein is not brittle after ion exchange. As used herein, the terms "frangible" and "frangibility" refer to the energetic fracture of a glass ceramic plate or sheet when subjected to a point impact by an object or a drop onto a hard surface with sufficient force to break the glass ceramic plate into a plurality of small pieces, which is: a plurality of crack branches in the glass (i.e., five or more crack branches from an initial crack); a protrusion of at least 2 inches (about 5 cm) from the original position of the piece; about five or more fragments / cm of the plate 2with a fragmentation density of; or any combination of any of these three conditions. Conversely, the glass-ceramic plate does not break, or the crack branching from the initial crack is less than 5, or the pieces break with the pieces protruding less than 2 inches (about 5 cm) from their original position when subjected to a point impact by an object or a drop onto a solid surface with sufficient force to break the glass-ceramic plate into a plurality of small pieces, then it is considered non-brittle.

[0081] The brittle and non-brittle behaviors observed for 5 cm × 5 cm glass-ceramic plates each having a thickness of 0.5 mm are shown in FIG. 10. Glass-ceramic plate a exhibits brittle behavior evidenced by a plurality of pieces protruding more than 2 inches (about 5 cm) and a high degree of crack branching from the initial crack that generates the pieces. In contrast to glass-ceramic plate a, glass-ceramic plates b, c, and d do not exhibit brittle behavior. In these examples, the glass-ceramic plates break into a few large pieces that do not protrude sharply more than 2 inches (about 5 cm) from their original position (the "X" is approximately the center of the glass plate before fragmentation). Glass-ceramic plate b breaks into two large pieces without crack branching; glass-ceramic plate c breaks into four pieces with two crack branches from the initial crack, and glass-ceramic plate d breaks into four pieces with two crack branches from the initial crack.

[0082] Furthermore, all compositions and glasses and / or glass-ceramic compositions are ion-exchangeable by methods well known in the art. In a typical ion-exchange process, relatively small metal ions in the glass are replaced or "exchanged" by relatively larger metal ions of the same valence in a layer near the outer surface of the glass and / or glass-ceramic. The replacement of relatively small metal ions by relatively large metal ions generates a compressive stress in the layer of the glass and / or glass-ceramic. In one embodiment, these metal ions are monovalent alkali metal ions (e.g., Na + , K + , Rb + , Cs +etc.), and ion exchange is achieved by immersing the glass and / or glass ceramic in a bath containing at least one molten salt of the relatively large metal ion that will replace the relatively small metal ion in the glass. Alternatively, the monovalent ion can be replaced with other monovalent ions such as Ag + , Tl + , Cu + etc. One or more ion exchange processes used to strengthen the glass and / or glass ceramic include, but are not limited to, immersion in a single bath or multiple baths of the same or different compositions with cleaning and / or annealing steps between immersions. In one or more embodiments, the glass and / or glass ceramic may be ion exchanged by exposure to molten NaNO3 at about 430 °C. In such an embodiment, Na+ ions replace some of the Li ions in the glass ceramic to grow a surface compression layer and exhibit high crack resistance. The resulting compressive stress layer can have a depth of at least 100 μm (also referred to as "layer depth") on the surface of the glass in about 2 hours. In such an embodiment, the layer depth can be determined from the Na2O concentration profile. In other examples, embodiments may be ion exchanged by exposure to molten KNO3 at 410 °C for 2 hours, thereby producing a compressive stress layer having a layer depth of at least about 100 μm. In some embodiments, the glass ceramic may be ion exchanged to achieve a layer depth of about 30 μm or more, about 40 μm or more, about 50 μm or more, about 60 μm or more, about 70 μm or more, about 80 μm or more, about 90 μm or more, or about 100 μm or more. In other embodiments, central tension of at least 10 MPa is achieved by ion exchanging the glass. The growth of this surface compression layer is beneficial for achieving good crack resistance and high flexural strength compared to non-ion exchanged materials. The concentration of ions exchanged into the glass ceramic article within the surface compression layer is higher than the concentration of ions exchanged into the glass ceramic article with respect to the body of the glass ceramic article (i.e., the region not including the surface compression layer).

[0083] In some embodiments, the glass ceramic can have a surface compressive stress in the range of about 100 MPa to about 500 MPa, about 100 MPa to about 450 MPa, about 100 MPa to about 400 MPa, about 100 MPa to about 350 MPa, about 100 MPa to about 300 MPa, about 100 MPa to about 250 MPa, about 100 MPa to about 200 MPa, about 100 MPa to about 150 MPa, 150 MPa to about 500 MPa, about 150 MPa to about 450 MPa, about 150 MPa to about 400 MPa, about 150 MPa to about 350 MPa, about 150 MPa to about 300 MPa, about 150 MPa to about 250 MPa, about 150 MPa to about 200 MPa, 200 MPa to about 500 MPa, about 200 MPa to about 450 MPa, about 200 MPa to about 400 MPa, about 200 MPa to about 350 MPa, about 200 MPa to about 300 MPa, about 200 MPa to about 250 MPa, 250 MPa to about 500 MPa, about 250 MPa to about 450 MPa, about 250 MPa to about 400 MPa, about 250 MPa to about 350 MPa, about 250 MPa to about 300 MPa, 300 MPa to about 500 MPa, about 300 MPa to about 450 MPa, about 300 MPa to about 400 MPa, about 300 MPa to about 350 MPa, 350 MPa to about 500 MPa, about 350 MPa to about 450 MPa, about 350 MPa to about 400 MPa, 400 MPa to about 500 MPa, about 400 MPa to about 450 MPa, or about 450 MPa to about 500 MPa. In some embodiments, the glass ceramic can have a surface compressive stress of about 100 MPa or more, about 150 MPa or more, about 200 MPa or more, about 250 MPa or more, about 300 MPa or more, about 350 MPa or more, about 400 MPa or more, about 450 MPa or more, or 500 MPa or more. The compressive stress and depth of layer (the "DOL") of the compressive stress layer are measured using means known in the art.DOL uses commercially available equipment such as the FSM-6000 manufactured by LUCEO Co., Ltd. (Tokyo, Japan), etc., and is determined by a surface stress meter (FSM). Also, the measurement methods for CS and layer depth are described in ASTM 1422C-99 "Standard Specification for Chemically Strengthened Flat Glass" and ASTM 1279.19779 "Standard Test Method for Nondestructive Photoelastic Measurement of Edge and Surface Stress of Annealed, Heat-Strengthened, and Fully Strengthened Flat Glass", and the entire contents of these are incorporated herein by reference. The surface stress measurement depends on the accurate measurement of the stress optical coefficient (SOC), which is related to the birefringence of the glass. The SOC is measured by methods known in the art, such as the fiber method, four-point bending method, and bulk cylinder method described in ASTM Standard C770-98 (2008) "Standard Test Method for Measurement of Stress-Optical Coefficient of Glass" (the entire contents of which are incorporated herein by reference).

[0084] In one or more embodiments, the process for making the glass ceramic includes heat treating a precursor glass at one or more preselected temperatures for one or more preselected times to induce homogenization of the glass and crystallization (i.e., nucleation and growth) of one or more crystalline phases (e.g., having one or more of composition, amount, morphology, size, or size distribution). In some embodiments, the heat treatment comprises: (i) heating the precursor glass at a rate of 1 - 10 °C / min to a glass pre-nucleation temperature; (ii) maintaining the crystallizable glass at the glass pre-nucleation temperature for a time of about 1 / 4 hour to about 4 hours to produce a pre-nucleated crystallizable glass; (iii) heating the pre-nucleated crystallizable glass at a rate of 1 - 10 °C / min to a nucleation temperature (Tn); (iv) maintaining the crystallizable glass at the nucleation temperature for a time of about 1 / 4 hour to about 4 hours to produce a nucleated crystallizable glass; (v) heating the nucleated crystallizable glass at a rate of about 1 °C / min to about 10 °C / min to a crystallization temperature (Tc); (vi) maintaining the nucleated crystallizable glass at the crystallization temperature for a time of about 1 / 4 hour to about 4 hours to produce the glass ceramic described herein; and (vii) cooling the formed glass ceramic to room temperature. As used herein, the term "crystallization temperature" may be used interchangeably with "ceramming temperature". Further, in these embodiments, the term "ceramming" may be used to collectively refer to steps (v), (vi), and optionally (vii). In some embodiments, the glass pre-nucleation temperature may be 540 °C, the nucleation temperature may be 600 °C, and the crystallization temperature may be in the range of 630 °C to 730 °C. In other embodiments, the heat treatment does not include the step of maintaining the crystallizable glass at the glass pre-nucleation temperature.Accordingly, the heat treatment may include: (i) heating the precursor glass at a rate of 1-10 °C / min to the nucleation temperature (Tn); (ii) maintaining the crystallizable glass at the nucleation temperature for a time period of about 1 / 4 hour to about 4 hours to produce a nucleated crystallizable glass; (iii) heating the nucleated crystallizable glass at a rate of about 1 °C / min to about 10 °C / min to the crystallization temperature (Tc); (iv) maintaining the nucleated crystallizable glass at the crystallization temperature for a time period of about 1 / 4 hour to about 4 hours to produce the glass-ceramic described herein; and (v) cooling the formed glass-ceramic to room temperature. In the above embodiments, the term "ceramming" may be used to collectively refer to steps (iii), (iv) and optionally (v). In some embodiments, the nucleation temperature may be about 700 °C and the crystallization temperature may be about 800 °C. In some embodiments, the higher the crystallization temperature, the more β-spodumene ss is produced as a small amount of crystalline phase.

[0085] In addition to the precursor glass composition, by carefully formulating the temperature-time profile of the heat treatment steps of heating to the crystallization temperature and maintaining the temperature at the crystallization temperature, one or more of the following desired attributes are produced: one or more crystalline phases of the glass-ceramic; the ratio of one or more major crystalline phases and / or one or more minor crystalline phases and the residual glass; the crystal phase constitution of one or more dominant crystalline phases and / or one or more minor crystalline phases and the residual glass; and the particle size or particle size distribution of one or more major crystalline phases and / or one or more minor crystalline phases. These can affect the final integrity, quality, color and / or opacity of the resulting glass-ceramic.

[0086] The resulting glass-ceramic can be provided as a sheet, which can subsequently be reformed into a curved or bent piece of uniform thickness by pressing, blowing, bending, sagging, vacuum forming, or other means. The reformation can be carried out prior to the heat treatment, or the forming step can also act as a heat treatment step that performs the forming and heat treatment substantially simultaneously.

[0087] In yet other embodiments, the precursor glass composition used to form the glass-ceramic can be formulated, for example, such that the glass-ceramic can be chemically strengthened using one or more ion exchange techniques. In these embodiments, the ion exchange can be carried out by exposing one or more surfaces of the glass-ceramic to one or more ion exchange baths having a specific composition and temperature for a specified period of time, thereby imparting one or more compressive stress layers to the one or more surfaces. The compressive stress layer(s) can include one or more average surface compressive stresses (CS), and / or one or more layer depths.

Examples

[0088] Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperatures, etc.), but some errors and deviations are to be included. Unless otherwise indicated, temperatures are expressed in °C or are ambient temperatures, and pressures are atmospheric or near atmospheric pressure. The compositions themselves are given in weight % on an oxide basis and are normalized to 100%. There are numerous variations and combinations of reaction conditions, such as component concentrations, temperatures, pressures, and other reaction ranges and conditions that can be used to optimize the purity and yield of the products obtained from the processes described herein. Optimization of such process conditions requires only reasonable and conventional experimentation.

[0089] Example 1 The compositional (wt%) and properties of exemplary glasses and glass-ceramics for obtaining transparent glass-ceramics are set forth in Table 1. These were determined according to techniques conventional in the glass art. Precursors glasses having Compositions 1-16 listed in Table 1 were formed. These precursor glasses were then subjected to a ceramization cycle, where they were held at 540°C for 4 hours for glass homogenization, held at 600°C for 4 hours for nucleation, and held in the temperature range of 630-730°C for 4 hours for crystallization. In Table 1, the following terms were used to describe the ceramization cycle: glass homogenization temperature - holding time / nucleation temperature - holding time / crystallization temperature - holding time.

[0090] The liquidus temperature is the temperature at which the first crystals are observed in a standard gradient boat liquidus measurement (ASTM C829-81 and its subsections). This involves placing comminuted glass particles in a platinum boat, placing the boat in a furnace having a gradient temperature in a region, heating the boat in an appropriate temperature region for 24 or 72 hours, and determining, by microscopic examination, the highest temperature at which crystals appear within the glass. More specifically, one piece of the glass sample is removed from the Pt boat and examined using a polarized light microscope to identify the position and nature of the crystals formed at the boundary between Pt and air and within the sample. Since the gradient of the furnace is well known, the temperature versus position can be reasonably estimated within 5-10°C. The temperature at which crystals are observed within the sample is understood to represent the liquidus of the glass (for the corresponding test period). In some cases, the test is carried out for a longer time (e.g., 72 hours) to observe the slower growing phase. The liquid phase viscosity (poise) was determined from the liquidus temperature and the coefficients of the Fulcher equation.

[0091]

Table 1-1

[0092]

Table 1-2

[0093] Multiple tests were performed on Composition 2 after ceramization to determine various properties of the glass ceramic of Composition 2. As shown in FIG. 1, a differential scanning calorimetry (DSC) trace was performed on Composition 2, and DSC / (mW / mg) was plotted against temperature (°C). Using this trace, it was shown that a micronized microstructure could be achieved by ceramization at a low temperature with respect to the crystallization temperature.

[0094] The transmittance of a 1-mm-thick glass ceramic Composition 2 was measured for light in the range of 400 nm to 1000 nm. As shown in FIG. 2, the average transmittance of the glass ceramic Composition 2 at visible light wavelengths is over 90%.

[0095] A sample of the glass ceramic Composition 2 was observed using a scanning electron microscope (SEM) to determine the particle size of petalite. FIG. 3A shows the SEM at a 200-nm scale, and FIG. 3B shows the SEM at a 100-nm scale. The petalite particles are on the order of 50 to 100 nm. The fineness of the particles is thought to contribute to the transparency of the glass ceramic demonstrated in FIG. 2.

[0096] Two 50 mm×50 mm×1 mm samples of the glass ceramic Composition 2 were subjected to the ring-on-ring test as described above to determine the strength of the samples. One sample was subjected to abrasion (15 psi (103421.4 Pa)), and the other sample was not subjected to abrasion. FIG. 4 shows the results of this ring-on-ring test. For the above ring-on-ring test, a strength of 514 MPa was achieved.

[0097] The fracture toughness of a sample of the glass ceramic Composition 2 was measured using a Chevron notch specimen measurement. The fracture toughness was 1.13 MPa·m 1 / 2 and that's it.

[0098] The hardness of a sample of the glass-ceramic composition was measured, and the Vickers hardness was determined as described above using a Model 5948 MicroTester available from Instron. The Vickers hardness was approximately 750 kgf / mm 2 (about 7355 N / mm 2 ).

[0099] The glass-ceramic of Composition 2 was subjected to an ion-exchange process. Here, the above sample was placed in a molten NaNO3 bath at 430 °C for 2 hours, 4 hours, 8 hours, and 16 hours. As shown in Figure 5, a layer depth of more than 100 μm was achieved. Figure 5 also shows a plot of the concentration (mole percent) of Na2O versus the thickness of the sample for each ion-exchange treatment. As can be confirmed, the layer depth increased as the duration of the ion-exchange treatment increased. Also, a parabolic Na2O was achieved after 16 hours of ion exchange.

[0100] Two 50 mm × 50 mm × 1 mm samples of the glass-ceramic of Composition 2 were ion-exchanged. One sample was ion-exchanged in a molten NaNO3 bath at 430 °C for 2 hours, and the other sample was ion-exchanged in a molten KNO3 bath at 430 °C for 2 hours. These two ion-exchanged 50 mm × 50 mm × 1 mm samples of the glass-ceramic of Composition 2 were subjected to a ring-on-ring test as described above. The results are shown in Figure 6. The strength of this glass-ceramic increased by approximately 30% after ion-exchange using NaNO3 and approximately doubled after ion-exchange using KNO3. It is considered that the depth of layer (DOL) of the compressive stress layer formed on the sample surface during ion-exchange is larger in the ion-exchange using the KNO3 bath.

[0101] A 50 mm × 50 mm × 1 mm sample of the glass ceramic of Composition 2 was ion-exchanged in a molten NaNO3 bath at 430 °C for 2 hours. A 50 mm × 50 mm × 1 mm sample of Glass A was ion-exchanged in a molten KNO3 bath at 420 °C for 5.5 hours. A 50 mm × 50 mm × 1 mm sample of Glass B was ion-exchanged in a 32% KNO3 molten bath at 540 °C for 8 hours and then ion-exchanged in a 100% KNO3 molten bath at 390 °C for 15 minutes. All of these samples were abraded at 15 psi (103421.4 Pa) and subjected to the ring-on-ring wear test as described above. The results are shown in Fig. 7. The above glass ceramic had a higher strength than Glass A and a strength close to that of Glass B. Therefore, this ion-exchanged glass ceramic can have a strength equal to or slightly higher than that of ion-exchanged glass.

[0102] A 50 mm × 50 mm × 1 mm sample of the glass ceramic of Composition 2 was ion-exchanged in a molten NaNO3 bath at 430 °C for 2 hours, 4 hours, 8 hours, and 16 hours. Next, the ion-exchanged sample and the non-ion-exchanged glass ceramic sample of Composition 2 were subjected to the ring-on-ring test as described above. The results are shown in Fig. 8. The strength of the above glass ceramic increased based on the period of ion-exchange.

[0103] A 50 mm × 50 mm × 1 mm sample of the glass ceramic of Composition 2 was ion-exchanged in a molten NaNO3 bath at 430 °C for 16 hours. The sample was abraded at 15 psi (103421.4 Pa), 25 psi (172369 Pa), or 45 psi (310264.2 Pa) and subjected to the ring-on-ring wear test as described above. The results are shown in Fig. 9. The sample abraded at 15 psi (103421.4 Pa) showed fracture under a load of about 253 MPa, the sample abraded at 25 psi (172369 Pa) showed fracture under a load of about 240 MPa, and the sample abraded at 45 psi (310264.2 Pa) showed fracture under a load of about 201 MPa.

[0104] Example 2 Exemplary glass and glass-ceramic compositions (weight %) and properties for obtaining translucent glass-ceramics are set forth in Table 2. These were determined according to techniques conventional in the glass art. Precursors glasses having Compositions 17-29 listed in Table 2 were formed. These precursor glasses were then subjected to the ceramization cycles shown in Table 2 below.

[0105]

Table 2-1

[0106]

Table 2-2

[0107] The fracture toughness of samples of glass-ceramic Compositions 17, 18, and 22 was measured using Chevron notch specimen measurements. The fracture toughnesses were 1.2 MPa·m 1 / 2 , 1.13 MPa·m 1 / 2 , and 1.2 MPa·m 1 / 2 , respectively.

[0108] As shown in FIG. 11, a differential scanning calorimetry (DSC) trace was performed on Composition 18, and DSC / (mW / mg) was plotted against temperature (°C). FIG. 12 is an X-ray diffraction (XRD) spectrum of the crystalline phases formed in Composition 18. From this XRD spectrum, it can be confirmed that petalite and lithium disilicate are the main crystalline phases.

[0109] 50 mm × 50 mm × 1 mm samples of glass-ceramic Compositions 19, 20, and 21 were subjected to the ring-on-ring test as described above to determine the strength of the samples. FIG. 13 shows the results of this ring-on-ring test. For the above ring-on-ring test, strengths of 352 MPa, 304 MPa, and 313 MPa were achieved, respectively. Thus, for the translucent glass-ceramics disclosed herein, strengths in excess of 300 MPa can be achieved.

[0110] The glass ceramic of Composition 18, formed by batchwise incorporating 1.4 mol% of Na2O into the bulk glass, was subjected to an ion exchange process. Here, the sample was placed in a molten NaNO3 bath at 430 °C for 4 hours. As shown in Figure 14, a layer depth of more than 100 μm was achieved. Figure 14 also shows a plot of the concentration of Na2O (weight percent) against the thickness of the sample.

[0111] Although a plurality of embodiments and examples have been given for illustrative purposes, the above description should not be construed as a limitation on the scope of the present disclosure or the appended claims. Accordingly, those skilled in the art can envision various modifications, adaptations, and alternatives without departing from the spirit and scope of the present disclosure or the appended claims.

[0112] Hereinafter, the preferred embodiments of the present invention will be described separately by item.

[0113] Embodiment 1 A petalite crystalline phase; and A lithium silicate crystalline phase A glass ceramic article comprising: The petalite crystalline phase and the lithium silicate crystalline phase have a higher weight percentage than other crystalline phases present in the glass ceramic article.

[0114] Embodiment 2 The glass ceramic article according to Embodiment 1, wherein the petalite crystalline phase constitutes 20 to 70% by weight of the glass ceramic article, and the lithium silicate crystalline phase constitutes 20 to 60% by weight of the glass ceramic article.

[0115] Embodiment 3 The glass ceramic article according to Embodiment 2, wherein the petalite crystalline phase constitutes 45 to 70% by weight of the glass ceramic article, and the lithium silicate crystalline phase constitutes 20 to 50% by weight of the glass ceramic article.

[0116] Embodiment 4 The petalite crystalline phase constitutes 40 to 60% by weight of the glass-ceramic article, and the lithium silicate crystalline phase constitutes 20 to 50% by weight of the glass-ceramic article, the glass-ceramic article according to Embodiment 2.

[0117] Embodiment 5 The lithium silicate crystalline phase is a lithium disilicate crystalline phase or a lithium metasilicate crystalline phase, the glass-ceramic article according to any one of Embodiments 1 to 4.

[0118] Embodiment 6 The article is transparent, the glass-ceramic article according to any one of Embodiments 1 to 5.

[0119] Embodiment 7 The article has a transmittance of at least 85% with respect to light in the wavelength range of 400 nm to 1000 nm at a thickness of 1 mm, the glass-ceramic article according to Embodiment 6.

[0120] Embodiment 8 The article has a transmittance of at least 90% with respect to light in the wavelength range of 400 nm to 1000 nm at a thickness of 1 mm, the glass-ceramic article according to Embodiment 6.

[0121] Embodiment 9 The article is translucent and has a transmittance in the range of 20 to less than 85% with respect to light in the wavelength range of 400 nm to 1000 nm at a thickness of 1 mm, the glass-ceramic article according to any one of Embodiments 1 to 5.

[0122] Embodiment 10 The glass-ceramic article is, in wt%: SiO2: 55 - 80%; Al2O3: 2 - 20%; Li2O: 5 - 20%; B2O3: 0 - 10%; Na2O: 0 - 5%; ZnO: 0 - 10%; P2O5: 0.5 - 6%; and ZrO2: 0.2 - 15% A glass - ceramic article according to any one of Embodiments 1 - 9, having a composition containing

[0123] Embodiment 11 The above - mentioned glass - ceramic article, by weight%: K2O: 0 - 4%; MgO: 0 - 8%; TiO2: 0 - 5%; CeO2: 0 - 0.4%; and SnO2: 0.05 - 0.5% A glass - ceramic article according to Embodiment 10, further having a composition containing

[0124] Embodiment 12 The above - mentioned glass - ceramic article, by weight%: SiO2: 69 - 80%; Al2O3: 6 - 9%; Li2O: 10 - 14%; B2O3: 0 - 12%; P2O5: 1.5 - 2.5%; and ZrO2: 2 - 4% A glass - ceramic article according to Embodiment 10, having a composition containing

[0125] Embodiment 13 The above - mentioned glass - ceramic article, by weight%: SiO2: 69 - 80%; Al2O3: 6 - 9%; Li2O: 10 - 14%; Na2O: 1 - 2%; K2O: 1 - 2%; B2O3: 0 - 12%; P2O5: 1.5 - 2.5%; and ZrO2: 2 - 4% A glass - ceramic article according to Embodiment 10, having a composition containing

[0126] Embodiment 14 The above - mentioned glass - ceramic article, by weight%: SiO2: 65 - 80%; Al2O3: 5 - 16%; Li2O: 8 - 15%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 2%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 6% A glass - ceramic article according to Embodiment 10, having a composition comprising the above.

[0127] Embodiment 15 The above glass - ceramic article, by weight%: SiO2: 60 - 80%; Al2O3: 5 - 20%; Li2O: 5 - 20%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 4%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 8% A glass - ceramic article according to Embodiment 10, having a composition comprising the above.

[0128] Embodiment 16 A glass - ceramic article according to Embodiment 10, wherein the total weight percentage of P2O5 and ZrO2 is more than 3.

[0129] Embodiment 17 The above glass - ceramic article has a fracture toughness of 1 MPa·m 1 / 2 or more, and is a glass - ceramic article according to any one of Embodiments 1 - 16.

[0130] Embodiment 18 The above glass - ceramic article has a Vickers hardness of about 600 kgf / mm 2 (about 5884 N / mm 2 ) or more, and is a glass - ceramic article according to any one of Embodiments 1 - 17.

[0131] Embodiment 19 The glass-ceramic article is the glass-ceramic article according to any one of Embodiments 1 to 18, having a surface compressive stress in the range of about 100 MPa to about 500 MPa.

[0132] Embodiment 20 The glass-ceramic article according to any one of Embodiments 1 to 19, further comprising a compressive stress layer having a layer depth (depth of layer: DOL) of at least about 30 μm.

[0133] Embodiment 21 The glass-ceramic article is the glass-ceramic article according to Embodiment 20, which is not brittle.

[0134] Embodiment 22 The glass-ceramic article according to any one of Embodiments 1 to 21, further comprising particles having a maximum dimension of 500 nm or less.

[0135] Embodiment 23 The glass-ceramic article according to any one of Embodiments 1 to 22, further comprising particles having a maximum dimension of 100 nm or less.

[0136] Embodiment 24 The glass-ceramic article is the glass-ceramic article according to any one of Embodiments 1 to 23, having a ring-on-ring strength of at least 300 MPa.

[0137] Embodiment 25 A method for forming a glass-ceramic article, wherein the method comprises: by weight: SiO2: 55 - 80%; Al2O3: 2 - 20%; Li2O: 5 - 20%; B2O3: 0 - 10%; Na2O: 0 - 5%; ZnO: 0 - 10%; P2O5: 0.5 - 6%; and ZrO2: 0.2 - 15% The step of forming a glass composition comprising; and The step of ceramifying the glass composition to form a glass-ceramic article comprising a petalite crystalline phase and a lithium silicate crystalline phase comprising wherein the petalite crystalline phase and the lithium silicate crystalline phase have a higher weight percentage than other crystalline phases present in the glass-ceramic article, a method.

[0138] Embodiment 26 The glass composition is, by weight:% K2O: 0 - 4%; MgO: 0 - 8%; TiO2: 0 - 5%; CeO2: 0 - 0.4%; and SnO2: 0.05 - 0.5% further comprising the method according to Embodiment 25.

[0139] Embodiment 27 The glass composition is, by weight:% SiO2: 69 - 80%; Al2O3: 6 - 9%; Li2O: 10 - 14%; B2O3: 0 - 12%; P2O5: 1.5 - 2.5%; and ZrO2: 2 - 4% comprising the method according to Embodiment 25.

[0140] Embodiment 28 The glass composition is, by weight:% SiO2: 69 - 80%; Al2O3: 6 - 9%; Li2O: 10 - 14%; Na2O: 1 - 2%; K2O: 1 - 2%; B2O3: 0 - 12%; P2O5: 1.5 - 2.5%; and ZrO2: 2 - 4% The method according to Embodiment 25, comprising

[0141] Embodiment 29 The glass composition is, by weight%: SiO2: 65 - 80%; Al2O3: 5 - 16%; Li2O: 8 - 15%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 2%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 6% The method according to Embodiment 25, comprising

[0142] Embodiment 30 The glass composition is, by weight%: SiO2: 60 - 80%; Al2O3: 5 - 20%; Li2O: 5 - 20%; Na2O: 0 - 3%; K2O: 0 - 3%; B2O3: 0 - 6%; ZnO: 0 - 4%; P2O5: 0.5 - 4%; and ZrO2: 0.2 - 8% The method according to Embodiment 25, comprising

[0143] Embodiment 31 The method according to any one of Embodiments 25 to 30, wherein the total weight percentage of P2O5 and ZrO2 is more than 3.

[0144] Embodiment 32 The method according to any one of Embodiments 25 to 31, further comprising the step of ion - exchanging the glass - ceramic article to form a compressive stress layer having a layer depth of at least 30 μm.

[0145] Embodiment 33 The step of ceramizing comprises the following consecutive steps: The step of heating the glass composition to the glass preliminary nucleation temperature; The step of maintaining the glass preliminary nucleation temperature for a predetermined period; The step of heating the composition to the nucleation temperature; The step of maintaining the nucleation temperature for a predetermined period; The step of heating the composition to the crystallization temperature; and The step of maintaining the crystallization temperature for a predetermined period The method according to any one of Embodiments 25 to 32, comprising the above.

[0146] Embodiment 34 The step of ceramizing comprises the following consecutive steps: The step of heating the composition to the nucleation temperature; The step of maintaining the nucleation temperature for a predetermined period; The step of heating the composition to the crystallization temperature; and The step of maintaining the crystallization temperature for a predetermined period The method according to any one of Embodiments 25 to 30, comprising the above.

[0147] Embodiment 35 The method according to any one of Embodiments 25 to 33, wherein the petalite crystalline phase constitutes 20 to 70% by weight of the glass-ceramic article, and the lithium silicate crystalline phase constitutes 20 to 60% by weight of the glass-ceramic article.

Claims

Claim 1 55% to 80% by weight of SiO ２ ; Al more than 6% by weight and up to 9% by weight ２ O ３ ; More than 10% by weight and up to 14% by weight of Li ２ O; Na₂O more than 0% by weight; Na more than 0% by weight and up to 2% by weight ２ O + K ２ O; P of 2% by weight to 4% by weight or less ２ O ５ ; and Precursor glass containing 3 wt% to 15 wt% or less of ZrO ２ ​ Claim 2 55% to 80% by weight of SiO ２ ; 6 wt% to 9 wt% of Al ２ O ３ ; More than 10% by weight and up to 14% by weight of Li ２ O; Na₂O more than 0% by weight; Na in an amount greater than 0% by weight and up to 2% by weight ２ O + K ２ O; P from 2% by weight to 3.5% by weight ２ O ５ ; and Precursor glass containing 3 wt% to 15 wt% or less of ZrO ２ ​ Claim 3 Sb ２ O ３ The precursor glass according to any one of claims 1 to 2, substantially free of Claim 4 P from 2% by weight to 3.5% by weight ２ O ５ The precursor glass according to claim 1, comprising Claim 5 ZrO ２ (wt%) + P ２ O ５ (wt%) is greater than 5, the precursor glass according to any one of claims 1 to 2. Claim 6 SiO from 70 wt% to 80 wt% ２ The precursor glass according to any one of claims 1 to 5, containing Claim 7 Li in an amount greater than 10% by weight and up to 12% by weight ２ The precursor glass according to any one of claims 1 to 6, containing O. Claim 8 ZrO from 3 wt% to 8 wt% ２ The precursor glass according to any one of claims 1 to 7, comprising Claim 9 TiO of 3 wt% or less ２ , MnO, ZnO, Nb ２ O ５ , MoO ３ , Ta ２ O ５ , WO ３ , ZrO ２ , Y ２ O 3 , La ２ O ３ , HfO ２ , CdO, Fe ２ O ３ , CeO ２ , or a combination thereof, the precursor glass according to any one of claims 1 to 8. Claim 10 Nb of 3 wt% or less ２ O ５ , Ta ２ O ５ , Y ２ O 3 , La ２ O ３ , HfO ２ , or a combination thereof, the precursor glass according to any one of claims 1 to 9. Claim 11 The precursor glass according to any one of Claims 1 to 10, having a thickness of 0.8 mm to 10 mm. Claim 12 The precursor glass according to any one of Claims 1 to 11, having a thickness of 6 mm or less.

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