CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 61/909,049 filed on Nov. 26, 2013.

BACKGROUND

The disclosure relates to alkali aluminosilicate glasses that are ion exchangeable to high compressive stresses, have fast ion exchange kinetics, and high intrinsic damage resistance.

SUMMARY

The present disclosure provides alkali aluminosilicate glasses that are ion exchangeable to high compressive stresses, have fast ion exchange kinetics, and high intrinsic damage resistance. The glasses described herein achieve all of the above desired properties either with only small amounts of P₂O₅(<1 mol %) or without addition of any P₂O₅.

Accordingly, one aspect of the disclosure is to provide a glass comprising: from about 50 mol % to about 72 mol % SiO₂; from about 12 mol % to about 22 mol % Al₂O₃; up to about 6.5 mol % B₂O₃; up to about 1 mol % P₂O₅; from about 11 mol % to about 21 mol % Na₂O; up to about 0.95 mol % K₂O; up to about 4 mol % MgO; up to about 5 mol % ZnO; and up to about 2 mol % CaO. In some embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦2.0 mol. In some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>1 mol %. In some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>1 mol %. In some embodiments, 24 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag.

A second aspect of the disclosure is to provide a glass comprising from about 55 mol % to about 62 mol % SiO₂; from about 16 mol % to about 20 mol % Al₂O₃; from about 4 mol % to about 6.5 mol % B₂O₃; from about 14 mol % to about 18 mol % Na₂O; from about 0.2 mol % to about 0.75 mol % K₂O; up to about 0.5 mol % MgO; up to about 0.5 mol % ZnO; and up to about 0.5 mol % CaO, wherein the glass is substantially free of P₂O₅. In some embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol %. In some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %. In some embodiments, 28 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag. In some embodiments, the glasses are substantially free of TiO₂.

Another aspect is to provide a method of ion exchanging a glass. The method comprises ion exchanging an alkali aluminosilicate glass for up to about eight hours in an ion exchange bath at a temperature of about 410Â° C. or less. The ion exchange bath comprises a potassium salt and the alkali aluminosilicate glass comprising: from about 50 mol % to about 72 mol % SiO₂; from about 12 mol % to about 22 mol % Al₂O₃; up to about 6.5 mol % B₂O₃; up to about 1 mol % P₂O₅; from about 11 mol % to about 21 mol % Na₂O; up to about 0.95 mol % K₂O; up to about 4 mol % MgO; up to about 5 mol % ZnO; and up to about 1 mol % CaO. The ion exchanged alkali aluminosilicate glass has a compressive layer extending from a surface to a depth of layer DOL, the compressive layer having a compressive stress CS of at least about 500 MPa. In some embodiments, the glasses are substantially free of TiO₂.

These and other aspects, advantages, and salient features will become apparent from the following detailed description, the accompanying drawings, and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view of an ion exchanged glass article.

DETAILED DESCRIPTION

In the following description, like reference characters designate like or corresponding parts throughout the several views shown in the FIGURES. It is also understood that, unless otherwise specified, terms such as â€œtop,â€ â€œbottom,â€ â€œoutward,â€ â€œinward,â€ and the like are words of convenience and are not to be construed as limiting terms. In addition, whenever a group is described as comprising at least one of a group of elements and combinations thereof, it is understood that the group may comprise, consist essentially of, or consist of any number of those elements recited, either individually or in combination with each other. Similarly, whenever a group is described as consisting of at least one of a group of elements or combinations thereof, it is understood that the group may consist of any number of those elements recited, either individually or in combination with each other. Unless otherwise specified, a range of values, when recited, includes both the upper and lower limits of the range as well as any ranges therebetween. As used herein, the indefinite articles â€œa,â€ â€œan,â€ and the corresponding definite article â€œtheâ€ mean â€œat least oneâ€ or â€œone or more,â€ unless otherwise specified. It also is understood that the various features disclosed in the specification and the drawings can be used in any and all combinations.

As used herein, the terms â€œglass articleâ€ and â€œglass articlesâ€ are used in their broadest sense to include any object made wholly or partly of glass. Unless otherwise specified, all compositions are expressed in terms of mole percent (mol %). Coefficients of thermal expansion (CTE) are expressed in terms of 10^âˆ’7/Â° C. and represent a value measured over a temperature range from about 20Â° C. to about 300Â° C., unless otherwise specified.

As used herein, the term â€œanneal point,â€ refers to the temperature at which a glass has a viscosity of 10^13.2poise, the term â€œstrain pointâ€ refers to the temperature at which a glass has a viscosity of 10^14.7poise, and the term â€œsoftening pointâ€ refers to the temperature at which glass visibly softens under its own weight.

It is noted that the terms â€œsubstantiallyâ€ and â€œaboutâ€ may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. Thus, a glass that is â€œsubstantially free of MgOâ€ is one in which MgO is not actively added or batched into the glass, but may be present in very small amounts as a contaminant.

Vickers crack initiation thresholds described herein are determined by applying and then removing an indentation load to the glass surface at a rate of 0.2 mm/min. The maximum indentation load is held for 10 seconds. The indentation cracking threshold is defined at the indentation load at which 50% of 10 indents exhibit any number of radial/median cracks emanating from the corners of the indent impression. The maximum load is increased until the threshold is met for a given glass composition. All indentation measurements are performed at room temperature in 50% relative humidity.

Compressive stress and depth of layer are measured using those means known in the art. Such means include, but are not limited to, measurement of surface stress (FSM) using commercially available instruments such as the FSM-6000, manufactured by Luceo Co., Ltd. (Tokyo, Japan), or the like, and methods of measuring compressive stress and depth of layer are described in ASTM 1422C-99, entitled â€œStandard Specification for Chemically Strengthened Flat Glass,â€ and ASTM 1279.19779 â€œStandard Test Method for Non-Destructive Photoelastic Measurement of Edge and Surface Stresses in Annealed, Heat-Strengthened, and Fully-Tempered Flat Glass,â€ the contents of which are incorporated herein by reference in their entirety. Surface stress measurements rely upon the accurate measurement of the stress optical coefficient (SOC), which is related to the birefringence of the glass. SOC in turn is measured by those methods that are known in the art, such as fiber and four point bend methods, both of which are described in ASTM standard C770-98 (2008), entitled â€œStandard Test Method for Measurement of Glass Stress-Optical Coefficient,â€ the contents of which are incorporated herein by reference in their entirety, and a bulk cylinder method.

Referring to the drawings in general and to FIG. 1 in particular, it will be understood that the illustrations are for the purpose of describing particular embodiments and are not intended to limit the disclosure or appended claims thereto. The drawings are not necessarily to scale, and certain features and certain views of the drawings may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.

Disclosed herein are alkali aluminosilicate glasses that are ion exchangeable to high compressive stresses, have fast ion exchange kinetics, and high intrinsic damage resistance. Previously, glasses exhibiting all three of these features contain large amounts of P₂O₅. The glasses described herein achieve all of the above desired properties either with only small amounts of P₂O₅(<1 mol %) or without addition of any P₂O₅.

Ion exchange is commonly used to chemically strengthen glasses. In one particular example, alkali cations within a source of such cations (e.g., a molten salt, or â€œion exchange,â€ bath) are exchanged with smaller alkali cations within the glass to achieve a layer that is under a compressive stress (CS) near the surface of the glass. For example, potassium ions from the cation source are often exchanged with sodium ions within the glass. Alternatively, other monovalent cations such as, Ag⁺, Cu⁺, Tl⁺, or the like may be introduced into the glass via such ion exchange. The compressive layer extends from the surface to a depth of layer (DOL) within the glass.

A cross-sectional schematic view of a planar ion exchanged glass article is shown in FIG. 1. Glass article 100 has a thickness t, first surface 110, and second surface 112. While the embodiment shown in FIG. 1 depicts glass article 100 as a flat planar sheet or plate, glass article may have other configurations, such as three dimensional shapes or non-planar configurations. Glass article 100 has a first compressive layer 120 extending from first surface 110 to a depth of layer d₁into the bulk of the glass article 100. In the embodiment shown in FIG. 1, glass article 100 also has a second compressive layer 122 extending from second surface 112 to a second depth of layer d₂. Glass article also has a central region 130 that extends from d₁to d₂. Central region 130 is under a tensile stress or central tension (CT), which balances or counteracts the compressive stresses of layers 120 and 122. The depth d₁, d₂of first and second compressive layers 120, 122 protects the glass article 100 from the propagation of flaws introduced by sharp impact to first and second surfaces 110, 112 of glass article 100, while the compressive stress minimizes the likelihood of a flaw penetrating through the depth d₁, d₂of first and second compressive layers 120, 122.

The high amounts of Al₂O₃(12 mol % to 22 mol %) and Na₂O (11 mol % to 21 mol %) in the glasses described herein enable the glass to be ion exchanged to achieve high levels of compressive stress CS. In some embodiments, the glasses described herein may be ion exchanged to produce compressive layers 120, 122 having a compressive stress CS of at least about 500 MPa; in some embodiments, at least about 700 MPa; in other embodiments, at least about 800 MPa; in other embodiments, at least about 900 MPa; in other embodiments, at least about 1000 MPa; and, in still other embodiments, at least about 1100 MPa. In some embodiments, the glasses described herein may be ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 52 Î¼m within eight hours ion exchange time. In other embodiments, the glasses described herein may be ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 40 Î¼m within four hours ion exchange time. In still other embodiments, the glasses described herein may be ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 30 Î¼m within two hours ion exchange time. In some embodiments, the compressive stress is in a range from about 700 MPa to about 1200 MPa; in other embodiments, from about 800 MPa to about 1200 MPa; in still other embodiments, from about 900 MPa to about 1200 MPa.

When ion exchanged, the glasses described herein exhibit intrinsic damage resistance, as reflected by Vickers indentation threshold measurements, described hereinabove. When the value of the expression B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃) is high (>1 mol %) and the value of (Na₂O+K₂Oâˆ’Al₂O₃) is low 0.5 mol %), the lass exhibits high levels of damage resistance. In some embodiments, the ion exchanged glass has a Vickers crack indentation threshold of at least about 9.5 kgf; in some embodiments, at least about 17.5 kgf; in other embodiments, at least about 22.5 kgf; in other embodiments, at least about 32.5 kgf; and, in still other embodiments, at least about 40 kgf.

High rates of ion exchange are attributable to the combination of several compositional factors, including high concentrations of Al₂O₃(12 mol % to 22 mol %) and RAlO₄(24 mol % to 45 mol %); a non-zero K₂O concentration (up to about 0.95 mol % K₂O); and low concentration (0 mol % to 5 mol %) of divalent metal oxides RO(Râ€² is at least one of Ca. Mg, and Zn). In some embodiments, the glasses described herein are ion exchangeable at a rate to achieve a CSÂ·DOL product of at least 44000 MPaÂ·Î¼m within less than about 8 hours.

The glasses described herein, in some embodiments, have a liquidus viscosity of at least about 100 kiloPoise (kpoise), which enables them to be made using down-draw techniques known in the art, such as fusion draw and slot draw methods. In particular, these glasses are compatible (i.e., do not substantially react with or degrade) with alumina hardware, such as isopipes) used in the fusion draw process.

In some embodiments, the glasses described herein consist essentially of or comprise: from about 50 mol % to about 72 mol % SiO₂(i.e., 50 mol %â‰¦SiO₂â‰¦72 mol %); from about 12 mol % to about 22 mol % Al₂O₃(i.e., 12 mol %â‰¦Al₂O₃â‰¦22 mol %); up to about 6.5 mol % B₂O₃(i.e., 0 mol %â‰¦B₂O₃â‰¦6.5 mol %); up to about 1 mol % P₂O₅(i.e., 0 mol %â‰¦P₂O₅â‰¦1 mol %); from about 11 mol % to about 21 mol % Na₂O (i.e., 11 mol %â‰¦Na₂Oâ‰¦21 mol %); up to about 0.95 mol % K₂O (i.e., 0 mol %â‰¦K₂Oâ‰¦0.95 mol %); up to about 4 mol % MgO (i.e., 0 mol %â‰¦MgOâ‰¦4 mol %); up to about 5 mol % ZnO (i.e., 0 mol %â‰¦ZnOâ‰¦4 mol %); and up to about 2 mol % CaO (i.e., 0 mol %â‰¦CaOâ‰¦2 mol %). In some embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦2.0 mol % and, in some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>1 mol %. In some embodiments, 24 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag. In some embodiments, 56 mol %â‰¦SiO₂+B₂O₃â‰¦78 mol % and, in some embodiments, 0 mol %â‰¦Î£[Râ€²O]â‰¦5 mol %, where Râ€² is at least one of Ca. Mg, and Zn. In some embodiments, 2 mol %â‰¦B₂O₃+P₂O₅â‰¦7.5 mol %. In some embodiments, the glasses described herein are substantially free of TiO₂.

In certain embodiments, the glass is substantially free of, or contains 0 mol %, P₂O₅. The glass, in some embodiments, is substantially free of, or contains 0 mol %, Li₂O. In some embodiments, the glass is substantially free of As₂O₃and Sb₂O₅.

In some embodiments, the glass may further include at least one fining agent such as SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl^âˆ’, F^âˆ’, or the like. In some embodiments, the glass may include up to about 0.5 mol % SnO₂(i.e., 0 mol %â‰¦SnO₂â‰¦0.5 mol %); up to about 0.5 mol % Sb₂O₅, (i.e., 0 mol %â‰¦CeO₂â‰¦0.5 mol %); and/or up to about 0.5 mol % As₂O₃(i.e., 0 mol %â‰¦As₂O₃â‰¦0.5 mol %.

In particular embodiments, the glasses consist essentially of or comprise: from about 55 mol % to about 62 mol % SiO₂(i.e., 55 mol %â‰¦SiO₂â‰¦62 mol %); from about 16 mol % to about 20 mol % Al₂O₃(i.e., 16 mol %<Al₂O₃â‰¦20 mol %); from about 2 mol % to about 6.5 mol % B₂O₃(i.e., 2 mol %â‰¦B₂O₃â‰¦6.5 mol %); up to about 1 mol % P₂O₅(i.e., 0 mol %â‰¦P₂O₅â‰¦1 mol %); from about 14 mol % to about 18 mol % Na₂O (i.e., 14 mol %â‰¦Na₂Oâ‰¦18 mol %); from about 0.2 mol % to about 0.75 mol % K₂O (i.e., 0.2 mol %â‰¦K₂Oâ‰¦0.95 mol %); up to about 0.5 mol % MgO (i.e., 0 mol %â‰¦MgOâ‰¦0.5 mol %); up to about 0.5 mol % ZnO (i.e., 0 mol %â‰¦ZnOâ‰¦0.5 mol %); and up to about 0.5 mol % CaO (i.e., 0 mol %â‰¦CaOâ‰¦0.5 mol %). In some embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol % and, in some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %. In some embodiments, 24 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag. In some embodiments, 56 mol %â‰¦SiO₂+B₂O₃â‰¦75 mol % and, in some embodiments, 0 mol %â‰¦Î£[Râ€²O]â‰¦0.5 mol %, where Râ€² is at least one of Ca. Mg, and Zn. In some embodiments, K₂Oâ‰¦0.5(Na₂O+K₂O). In embodiments, the glass is substantially free, or contains 0 mol %, of TiO₂. In certain embodiments, the glass is substantially free of, or contains 0 mol %, P₂O₅. The glass, in some embodiments, is substantially free of, or contains 0 mol %, Li₂O. In other embodiments, the glass is substantially free, or contains 0 mol %, of As₂O₃and Sb₂O₅.

In embodiments, the glass may further include at least one fining agent such as SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl^âˆ’, F^âˆ’, or the like. In some embodiments, the glass may include up to about 0.5 mol % SnO₂(i.e., 0 mol %â‰¦SnO₂â‰¦0.5 mol %); up to about 0.5 mol % Sb₂O₅, (i.e., 0 mol %â‰¦CeO₂â‰¦0.5 mol %); and/or up to about 0.5 mol % As₂O₃(i.e., 0 mol %â‰¦As₂O₃â‰¦0.5 mol %.

In still other embodiments, the glasses described herein consist essentially of or comprise: from about 55 mol % to about 62 mol % SiO₂(i.e., 55 mol %â‰¦SiO₂â‰¦62 mol %); from about 16 mol % to about 20 mol % Al₂O₃(i.e., 16 mol %<Al₂O₃â‰¦20 mol %); from about 4 mol % to about 6.5 mol % B₂O₃(i.e., 4 mol %â‰¦B₂O₃â‰¦6.5 mol %); from about 14 mol % to about 18 mol % Na₂O (i.e., 14 mol %â‰¦Na₂Oâ‰¦18 mol %); from about 0.2 mol % to about 0.75 mol % K₂O (i.e., 0.2 mol %â‰¦K₂Oâ‰¦4 mol %); up to about 0.5 mol % MgO (i.e., 0 mol %â‰¦MgOâ‰¦0.5 mol %); up to about 0.5 mol % ZnO (i.e., 0 mol %â‰¦ZnOâ‰¦0.5 mol %); up to about 0.5 mol % CaO (i.e., 0 mol %â‰¦CaOâ‰¦0.5 mol %); and are substantially free of, or contain 0 mol %, P₂O₅. In some embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol % and, in some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %. In some embodiments, 28 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag. In some embodiments, 56 mol %â‰¦SiO₂+B₂O₃â‰¦70 mol % and, in some embodiments, 0 mol %â‰¦Î£[Râ€²O]â‰¦0.5 mol %, where Râ€² is at least one of Ca. Mg, and Zn. In some embodiments, K₂Oâ‰¦0.25(Na₂O+K₂O). In embodiments, the glass is substantially free of TiO₂. In certain embodiments, the glass is substantially free of, or contains 0 mol %, Li₂O. In some embodiments, the glass is substantially free of, or contains 0 mol %, As₂O₃and Sb₂O₅.

In some embodiments, the glass may further include at least one fining agent such as SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl^âˆ’, F^âˆ’, or the like. In some embodiments, the glass may include up to about 0.5 mol % SnO₂(i.e., 0 mol %â‰¦SnO₂â‰¦0.5 mol %); up to about 0.5 mol % Sb₂O₅, (i.e., 0 mol %â‰¦CeO₂â‰¦0.5 mol %); and/or up to about 0.5 mol % As₂O₃(i.e., 0 mol %â‰¦As₂O₃â‰¦0.5 mol %.

Compositions and non-limiting examples of these glasses that comprise P₂O₅are listed in Table 1. Compositions and non-limiting examples of these glasses that are substantially free of P₂O₅are listed in Table 2. Each of the oxide components of these glasses serves a function. Silica (SiO₂), for example, is the primary glass forming oxide, and forms the network backbone for the molten glass. Pure SiO₂has a low CTE and is alkali metal-free. Due to its extremely high melting temperature, however, pure SiO₂is incompatible with the fusion draw process. The viscosity curve is also much too high to match with any core glass in a laminate structure. In some embodiments, the amount of SiO₂in the glasses described herein ranges from about 50 mol % to about 72 mol %. In other embodiments, the SiO₂concentration ranges from about 55 mol % to about 62 mol %.

In addition to silica, the glasses described herein comprise the network formers Al₂O₃and B₂O₃to achieve stable glass formation, low CTE, low Young's modulus, low shear modulus, and to facilitate melting and/or forming. By mixing all three of these network formers in appropriate concentrations, it is possible achieve stable bulk glass formation while minimizing the need for network modifiers such as alkali or alkaline earth oxides, which act to increase CTE and modulus. Like SiO₂, Al₂O₃contributes to the rigidity to the glass network. Alumina may exist in the glass in either fourfold or fivefold coordination. In some embodiments, the glasses described herein comprise from about 12 mol % to about 22 mol % Al₂O₃and, in particular embodiments, from about 16 mol % to about 20 mol % Al₂O₃.

Boron oxide (B₂O₃) is also a glass-forming oxide that is used to reduce viscosity and thus improve the ability to melt and form glass. B₂O₃may exist in either threefold or fourfold coordination in the glass network. Threefold coordinated B₂O₃is the most effective oxide for reducing the Young's modulus and shear modulus, thus improving the intrinsic damage resistance of the glass. Accordingly, the glasses described herein, in some embodiments, comprise from about 0 mol % up to about 6.5 mol % B₂O₃, in other embodiments, from about 2 mol % to about 6.5 mol % B₂O₃, and in still other embodiments, from about 4 mol % to about 6.0 mol % B₂O₃. In some embodiments, 56 mol %â‰¦SiO₂+B₂O₃â‰¦78 mol % and, in other embodiments, 66 mol %â‰¦SiO₂+B₂O₃â‰¦75 mol %. In certain embodiments, B₂O₃â‰¦Al₂O₃.

The alkali oxides Na₂O and K₂O are used to achieve chemical strengthening of the glass by ion exchange. In some embodiments, the glass includes Na₂O, which can be exchanged for potassium in a salt bath containing, for example, KNO₃. In some embodiments, 0 mol %â‰¦K₂Oâ‰¦0.95 mol %, and, in certain embodiments, 0.2 mol %â‰¦K₂Oâ‰¦0.75 mol %. In some embodiments, 11 mol %â‰¦Na₂Oâ‰¦21 mol %, in other embodiments, 14 mol %â‰¦Na₂Oâ‰¦18 mol % In other embodiments, 1 mol %â‰¦Li₂Oâ‰¦15 mol %, and, in certain embodiments, 6 mol %â‰¦Li₂₀â‰¦13 mol %. The glasses described herein are substantially free of Li₂O, or comprise 0 mol % Li₂O. %). In some embodiments, Na₂O+K₂Oâˆ’Al₂O₃2.0 mol % and, in other embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol %. In some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>1 mol % and, in other embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %. In some embodiments, 24 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag, and, in other embodiments, 24 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag.

Like B₂O₃, alkaline earth oxides such as MgO and CaO, and other divalent oxides such as ZnO also improve the melting behavior of the glass. However, they also act to increase CTE and Young's and shear moduli. In some embodiments, the glasses described herein comprise up to about 4 mol % MgO, up to about 1 mol % CaO, and up to about 4 mol % ZnO. In other embodiments, these glasses may comprise up to about 0.5 mol % MgO, up to about 0.5 mol % CaO, and up to about 0.5 mol % ZnO. In some embodiments, 0 mol %â‰¦Î£[Râ€²O]â‰¦5 mol % and, in other embodiments, 0 mol %â‰¦Î£[Râ€²O]â‰¦0.5 mol %, where Râ€² is at least one of Ca. Mg, and Zn.

TiO₂is commonly used to lower the coefficient of thermal expansion is glasses. However, TiO₂may negatively impact the light transmitting properties of the glass, such as by absorbing and transmitting light that otherwise would not be absorbed or transmitted by the glass. Accordingly, in embodiments, the glass is substantially free of, or contains 0 mol %, TiO₂.

In order to ensure that the vast majority of B₂O₃in the glass is in the threefold coordinated state and thereby obtain a high native scratch resistance, Na₂O+K₂Oâˆ’Al₂O₃â‰¦2.0 mol % and, in some embodiments, Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol %. In some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>1 mol % and, and, in some embodiments, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %.

The glass may also include at least one fining agent such as SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl^âˆ’, F^âˆ’, or the like in small concentrations to aid in the elimination of gaseous inclusions during melting. In some embodiments, the glass may comprise up to about 0.5 mol % SnO₂, up to about 0.5 mol % As₂O₃, and/or up to about 0.5 mol % Sb₂O₃. However, As₂O₃and Sb₂O₃may have adverse affects on the environment and health. Therefore, in some embodiments, the glass is substantially free of, or contains 0 mol %, As₂O₃and Sb₂O₅.

Non-limiting examples of compositions and their selected physical properties (strain, anneal and softening points, density, CTE, liquidus temperatures, modulus, refractive index, and stress optical coefficient (SOC)) of the glasses described herein comprising up to about 1 mol % P₂O₅are listed in Table 1. Non-limiting examples of compositions and their selected physical properties of the glasses described herein that do not contain P₂O₅are listed in Table 2.

In another aspect, a method of ion exchanging the alkali aluminosilicate glasses described herein above is provided. The method comprises ion exchanging the glass at temperatures of up to about 410Â° C. for up to about eight hours in an ion exchange bath comprising a potassium salt to form a compressive layer having a compressive stress CS of at least 500 MPa and extending from a surface to a depth of layer DOL. In some embodiments, the glasses described herein may be ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 52 Î¼m within eight hours ion exchange time. In other embodiments, the glasses described herein may be ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 40 Î¼m within four hours ion exchange time. In still other embodiments, the glasses described herein may be ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 30 Î¼m within two hours ion exchange time. In some embodiments, CSÂ·DOL=44000 MPaÂ·Î¼m.

TABLE 1Compositions and selected physical properties of the glasses describedherein comprising up to about 1 mol % P₂O₅.Glass (mol %)ABCDESiO₂63.5364.6563.5864.5564.63Al₂O₃14.98141413.9714.38B₂O₃6.0466.9376.9837.0156.016Na₂O13.7612.7413.7513.7313.76K₂O0.5030.4960.5010.0050.501MgO0.0390.0370.0370.0420.02CaO0.070.070.0680.0680.064ZnO00000P₂O₅0.970.970.970.510.497SnO₂0.10.10.1010.0990.099[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’0.71âˆ’0.760.242âˆ’0.23âˆ’0.12[B₂O₃] âˆ’ ([Na₂O] + [K₂O] âˆ’ [Al₂O₃])6.767.7016.7417.2446.135Strain Pt. (Â° C.)590575559576570Anneal Pt. (Â° C.)649634613633629Soft Pt. (Â° C.)935906879914919CTE (10⁷Â° C.^âˆ’1)80.677.380.57880.3Density (g/cm³)2.3742.3612.3742.3672.378E Mod (Mpsi)9.269.149.2399.1659.357G Mod (Mpsi)3.8163.7643.7883.7783.864Î½ (Poisson's ratio)0.2130.2140.2190.2130.211Indentation Threshold (kgf)3027.5253032.5CS¹(MPa)803.4724.9733.1782.1792.5DOL¹(Î¼m)70.0964.2360.7558.7162.94¹Glass fusion drawn/fictivated and ion exchanged at 410Â° C. for 8 hours in KNO₃molten salt bath.

TABLE 2Compositions and selected physical properties of the glasses described herein that do not contain P₂O₅.Glass (mol %)123456SiO₂64.0563.9864.0263.9661.4462.02Al₂O₃13.5916.3515.8616.4116.8716.53B₂O₃8.114.003.982.135.404.95Na₂O13.5414.4014.8716.2515.5915.99K₂O0.511.021.021.010.510.51MgO0.020.020.020.020.020.01CaO0.070.130.130.130.070.07ZnOP₂O₅SnO₂0.100.100.100.100.090.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.46âˆ’0.930.020.85âˆ’0.77âˆ’0.04[B₂O₃] âˆ’ ([Na₂O] +7.654.943.961.286.174.99[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)542623599620600.8591.3Anneal Pt. (Â° C.)594684657679659.7649.2Soft Pt. (Â° C.)856980950969949CTE (10⁷Â° C.^âˆ’1)7984.686.389.3Density (g/cm³)2.3682.4062.4082.4332.398E Mod (Mpsi)9.3329.8719.879G Mod (Mpsi)3.8074.0444.042Î½ (Poisson's ratio)0.2260.2210.222Indentation Threshold (kgf)4017.517.511.542.527.5CS (MPa)¹945.98934.91936.13CS (MPa)¹(SOC corrected)904.22950.37DOL (Î¼m)¹75.8774.6673.9473.6572.07CS (MPa)²598.551025.881031.551048.43CS (MPa)²(SOC corrected)978.331069.76DOL (Î¼m)²45.9756.4157.4360.0659.4156.14Glass (mol %)789101112SiO₂58.0559.9462.0261.9264.4166.99Al₂O₃17.6616.4916.5316.8514.9513.31B₂O₃6.086.635.035.046.045.79Na₂O17.4916.2015.9115.6713.8913.74K₂O0.500.510.510.510.520.01MgO0.020.020.010.020.020.02CaO0.080.080.070.080.060.02ZnOP₂O₅SnO₂0.100.100.090.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.330.22âˆ’0.11âˆ’0.66âˆ’0.550.44[B₂O₃] âˆ’ ([Na₂O] +5.756.415.145.706.595.35[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)594588591602.6603594Anneal Pt. (Â° C.)648644649.4661.4662653Soft Pt. (Â° C.)907905946942CTE (10⁷Â° C.^âˆ’1)90.887.480.475.3Density (g/cm³)2.4122.3992.3812.365E Mod (Mpsi)9.529.4189.4389.309G Mod (Mpsi)3.8773.833.8653.848Î½ (Poisson's ratio)0.2280.2290.2210.21Indentation Threshold (kgf)22.532.527.5355032.5CS (MPa)¹982.26887.12836.34770.78CS (MPa)¹(SOC corrected)838.10951.64992.14786.73709.43DOL (Î¼m)¹71.2370.9170.8769.6469.4869.26CS (MPa)²1134.741090.05940.56920.95CS (MPa)²(SOC corrected)1029.811033.00884.78847.65DOL (Î¼m)²53.6751.2058.5853.1150.07Glass (mol %)131415161718SiO₂67.1467.1160.3161.6667.0866.96Al₂O₃13.2113.2316.4616.2213.2313.33B₂O₃5.775.766.505.095.775.79Na₂O13.4213.4216.0416.3313.4613.75K₂O0.260.260.510.510.260.01MgO0.020.020.020.020.020.02CaO0.050.050.070.070.050.02ZnOP₂O₅SnO₂0.100.100.090.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.470.450.090.620.490.43[B₂O₃] âˆ’ ([Na₂O] +5.305.306.414.465.275.36[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)593592569.4569.5591594Anneal Pt. (Â° C.)651650624.4622.9649652Soft Pt. (Â° C.)931938935942CTE (10⁷Â° C.^âˆ’1)76.876.576.375.6Density (g/cm³)2.3692.372.3962.4082.3682.369E Mod (Mpsi)9.4129.4539.5029.34G Mod (Mpsi)3.8733.8653.8453.849Î½ (Poisson's ratio)0.2150.2230.2360.213Indentation Threshold (kgf)27.5>2547.517.517.527.5CS (MPa)¹763.00767.19757.38783.96CS (MPa)¹(SOC corrected)707.18711.69833.11885.94701.16726.19DOL (Î¼m)¹69.2469.1768.8568.7968.7067.82CS (MPa)²901.59901.02899.76928.71CS (MPa)²(SOC corrected)835.64835.84958.061000.30832.97860.27DOL (Î¼m)²49.2550.4154.4550.8952.3348.49Glass (mol %)192021222324SiO₂62.3867.1465.6662.8657.4156.99Al₂O₃15.7113.2313.7115.3019.2019.12B₂O₃5.055.726.265.145.335.44Na₂O16.1713.4213.9116.0117.6517.97K₂O0.510.260.260.510.250.26MgO0.020.020.020.020.020.05CaO0.060.050.050.060.040.06ZnO0.00P₂O₅SnO₂0.100.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.970.450.461.22âˆ’1.30âˆ’0.89[B₂O₃] âˆ’ ([Na₂O] +4.085.265.803.926.636.33[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)565590586559.6627623Anneal Pt. (Â° C.)617.1649644610.4683678Soft Pt. (Â° C.)883.5936928941928CTE (10⁷Â° C.^âˆ’1)86.27677.688.292.6Density (g/cm³)2.4082.3672.372.4212.426E Mod (Mpsi)9.4219.359.7059.603G Mod (Mpsi)3.8583.8283.9673.942Î½ (Poisson's ratio)0.2210.2210.2230.218Indentation Threshold (kgf)1032.522.5103550CS (MPa)¹770.06775.411049.211009.69CS (MPa)¹(SOC corrected)819.65712.06715.97787.791029.47999.95DOL (Î¼m)¹67.1866.9366.9366.4966.4366.37CS (MPa)²893.63913.971211.521153.86CS (MPa) (SOC corrected)951.03826.33843.91931.001188.721142.72DOL (Î¼m)²53.0352.2750.3250.0949.3850.35Glass (mol %)252627282930SiO₂65.3465.8664.1162.8964.0665.45Al₂O₃13.8413.0814.0114.6714.8613.85B₂O₃6.416.967.156.906.016.29Na₂O14.2411.7213.0314.3113.8114.23K₂O0.012.011.500.991.010.01MgO0.020.020.010.020.020.02CaO0.020.240.070.110.120.02ZnOP₂O₅SnO₂0.100.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.410.660.530.62âˆ’0.030.38[B₂O₃] âˆ’ ([Na₂O] +6.006.306.626.286.055.91[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)589540560548570590Anneal Pt. (Â° C.)646592613599.9627646Soft Pt. (Â° C.)928851810920927CTE (10⁷Â° C.^âˆ’1)77.881.982.78278.5Density (g/cm³)2.3712.3792.3822.3852.3882.372E Mod (Mpsi)9.2559.6539.4679.6359.286G Mod (Mpsi)3.8123.9363.8743.9133.846v (Poisson's ratio)0.2140.2260.2220.2310.207Indentation Threshold (kgf)27.517.547.537.547.537.5CS (MPa)¹792.17644.93731.96844.33808.31CS (MPa)¹(SOC corrected)728.06688.85734.27746.13DOL (Î¼m)¹66.1065.8765.3565.1265.0064.89CS (MPa)²920.31738.35842.29935.14960.00CS (MPa)²(SOC corrected)845.84792.68844.88886.15DOL (Î¼m)²50.8252.2649.6250.3049.8647.59Glass (mol %)313233343536SiO₂64.1957.0766.0665.8462.8763.72Al₂O₃15.3618.7813.2213.1814.9614.96B₂O₃5.955.316.986.996.967.05Na₂O13.2218.3513.0412.7314.5213.57K₂O1.020.260.511.010.510.50MgO0.020.050.020.020.020.02CaO0.130.050.070.120.070.06ZnO0.00P₂O₅SnO₂0.100.100.100.100.090.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’1.12âˆ’0.170.330.560.07âˆ’0.88[B₂O₃] âˆ’ ([Na₂O] +7.075.486.656.436.887.93[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)586612550545559.9592Anneal Pt. (Â° C.)646667604598615.7651Soft Pt. (Â° C.)943921869866933CTE (10⁷Â° C.^âˆ’1)77.794.278.480.178.4Density (g/cm³)2.3862.432.3722.3772.376E Mod (Mpsi)9.5729.7289.4619.559.268G Mod (Mpsi)3.9383.9283.8733.8833.806Î½ (Poisson's ratio)0.2150.2380.2220.230.218Indentation Threshold (kgf)42.53017.517.542.550CS (MPa)¹851.23954.36692.07701.60809.55CS (MPa)¹(SOC corrected)941.04779.63759.29DOL (Î¼m)¹64.7263.8863.5763.1662.9162.89CS (MPa)²920.571152.17814.65810.37919.37CS (MPa)²(SOC corrected)1136.09885.76862.29DOL (Î¼m)²45.3351.1748.3146.0447.1847.57Glass (mol %)373839404142SiO₂65.3563.0765.8362.8565.7165.86Al₂O₃14.0015.4013.5915.4213.5713.56B₂O₃6.116.675.127.025.745.25Na₂O13.8414.1814.4514.0213.9714.32K₂O0.510.510.100.510.100.10MgO0.010.020.770.020.760.76CaO0.060.070.050.070.040.04ZnO0.000.000.00P₂O₅SnO₂0.100.090.100.090.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.34âˆ’0.710.96âˆ’0.900.510.86[B₂O₃] âˆ’ ([Na₂O] +5.767.384.167.925.244.40[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)580573.1584575.1586584Anneal Pt. (Â° C.)636631.6638633.3641639Soft Pt. (Â° C.)908907915911CTE (10⁷Â° C.^âˆ’1)79.578.576.477.7Density (g/cm³)2.3822.392.3732.3792.388E Mod (Mpsi)9.6149.7049.5589.609G Mod (Mpsi)3.8874.0073.9123.98Î½ (Poisson's ratio)0.2370.2110.2220.207Indentation Threshold (kgf)32.547.527.547.532.540CS (MPa)¹796.55809.68803.88811.46CS (MPa)¹(SOC corrected)749.86780.71784.04800.99764.68778.88DOL (Î¼m)¹62.8062.5062.4262.4162.0161.95CS (MPa)²911.571000.28946.44985.28CS (MPa)²(SOC corrected)858.13881.96968.60897.79900.29945.72DOL (Î¼m)²47.9047.0044.2546.5749.3545.17Glass (mol %)434445464748SiO₂64.5764.7850.5065.6165.5265.74Al₂O₃13.8513.6621.0913.5813.5913.57B₂O₃7.047.037.045.595.625.63Na₂O13.8413.8320.1214.2114.2514.05K₂O0.510.510.980.100.100.10MgO0.020.020.020.760.770.77CaO0.070.070.130.040.040.04ZnO0.000.000.00P₂O₅SnO₂0.100.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.500.680.010.730.760.58[B₂O₃] âˆ’ ([Na₂O] +6.546.357.034.864.855.05[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)550549.5569581581584Anneal Pt. (Â° C.)603601.5620637635639Soft Pt. (Â° C.)867.5864906906913CTE (10⁷Â° C.^âˆ’1)77.779.3100.977.676.776.6Density (g/cm³)2.382.3732.4442.3852.3842.382E Mod (Mpsi)9.5069.6699.6639.6089.651G Mod (Mpsi)3.8963.9063.9483.9423.92Î½ (Poisson's ratio)0.220.2380.2240.2190.231Indentation Threshold (kgf)37.537.512.537.532.540CS (MPa)¹741.35987.93802.89801.35810.58CS (MPa)¹(SOC corrected)689.48976.87766.03767.10763.97DOL (Î¼m)¹61.6461.5061.3661.3161.1160.80CS (MPa)²1137.60983.29965.09971.14CS (MPa)²(SOC corrected)775.201124.87938.15923.84915.30DOL (Î¼m)²50.4445.7644.6246.3946.48Glass (mol %)495051525354SiO₂65.4556.8864.4959.7764.4456.55Al₂O₃13.9818.3614.1816.1913.9918.28B₂O₃7.065.417.027.047.046.55Na₂O12.8118.8813.6116.2813.8317.37K₂O0.500.260.510.510.510.99MgO0.010.040.010.020.010.02CaO0.060.060.060.070.060.12ZnO0.000.00P₂O₅SnO₂0.100.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’0.670.77âˆ’0.060.600.350.07[B₂O₃] âˆ’ ([Na₂O] +7.734.647.086.446.696.47[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)588586578552.1571562Anneal Pt. (Â° C.)648640634602.8628616Soft Pt. (Â° C.)943892914858.6887867CTE (10⁷Â° C.^âˆ’1)75.497.279.57993.7Density (g/cm³)2.3632.4352.3722.3992.3752.42E Mod (Mpsi)9.1829.829.2979.3339.547G Mod (Mpsi)3.833.9753.8253.8353.871Î½ (Poisson's ratio)0.1990.2350.2150.2170.233Indentation Threshold (kgf)2012.537.542.537.527.5CS (MPa)¹754.06907.31795.79734.76923.25CS (MPa)¹(SOC corrected)691.64904.75741.57789.38679.62899.49DOL (Î¼m)¹60.6360.5860.3860.0759.9059.68CS (MPa)²865.341077.34906.33880.031042.81CS (MPa)²(SOC corrected)793.711074.30844.58930.97813.991015.97DOL (Î¼m)²45.1746.1346.5544.6346.0945.26Glass (mol %)555657585960SiO₂57.3263.7967.1864.2955.4256.81Al₂O₃19.1014.4412.7813.9518.4618.34B₂O₃4.375.665.656.947.245.64Na₂O17.7315.4213.7014.1318.4518.74K₂O0.250.500.000.510.250.25MgO1.060.010.540.020.010.04CaO0.050.060.020.070.050.06ZnO0.000.00P₂O₅SnO₂0.100.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’1.111.490.920.680.240.66[B₂O₃] âˆ’ ([Na₂O] +5.484.174.736.257.004.98[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)625553.3579550.4569577Anneal Pt. (Â° C.)678602.1633602.9621630Soft Pt. (Â° C.)934904870.7858893CTE (10⁷Â° C.^âˆ’1)88.775.579.494.395.6Density (g/cm³)2.4382.3762.3752.4242.434E Mod (Mpsi)9.8559.5479.579.703G Mod (Mpsi)4.0183.9253.8643.98Î½ (Poisson's ratio)0.2270.2160.2380.219Indentation Threshold (kgf)151017.537.532.512.5CS (MPa)¹1087.72747.21936.43913.84CS (MPa)¹(SOC corrected)1097.38745.92718.15910.69DOL (Î¼m)¹59.3459.3258.9858.6958.6058.58CS (MPa)²1214.15910.001081.85CS (MPa)²(SOC corrected)1224.94899.51805.33DOL (Î¼m)²45.3844.6242.8947.8045.12Glass (mol %)616263646566SiO₂64.3661.5663.8164.1464.4257.15Al₂O₃14.4915.7714.6414.7713.9418.43B₂O₃7.106.045.137.258.065.27Na₂O13.8515.9115.7413.5112.8718.97K₂O0.010.520.500.200.520.01MgO0.010.020.020.010.010.05CaO0.060.080.060.030.060.02ZnO0.00P₂O₅SnO₂0.100.100.100.070.100.09[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’0.630.661.60âˆ’1.06âˆ’0.550.55[B₂O₃] âˆ’ ([Na₂O] +7.735.383.538.318.614.72[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)591565553.8590574580.2195Anneal Pt. (Â° C.)650617602.8648631633.1365Soft Pt. (Â° C.)934888850934916CTE (10⁷Â° C.^âˆ’1)76.68875.475.2Density (g/cm³)2.372.4112.4082.3682.36E Mod (Mpsi)9.3159.5639.2579.148G Mod (Mpsi)3.7583.9193.8033.742Î½ (Poisson's ratio)0.2390.220.2170.222Indentation Threshold (kgf)42.512.51037.52012.5CS (MPa)¹807.46926.79790.43743.00971.44CS (MPa)¹(SOC corrected)731.13758.52718.78660.54965.67DOL (Î¼m)¹58.5058.2557.9257.9057.6857.60CS (MPa)²917.911054.95930.21849.331097.45CS (MPa)²(SOC corrected)831.14893.72845.89755.071090.93DOL (Î¼m)²43.6544.9746.8743.6943.4045.43Glass (mol %)676869707172SiO₂56.2364.6562.8359.7658.1956.21Al₂O₃17.6413.9414.9217.1117.2018.31B₂O₃8.056.986.945.407.066.14Na₂O16.7814.2014.6317.5416.2918.87K₂O0.990.100.510.020.990.26MgO0.050.010.010.050.020.05CaO0.140.020.060.030.120.06ZnO0.000.00P₂O₅SnO₂0.100.070.090.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.130.360.220.450.080.83[B₂O₃] âˆ’ ([Na₂O] +7.926.626.724.956.985.31[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)557571558.9579.1148557572Anneal Pt. (Â° C.)608622613.1631.8197610622Soft Pt. (Â° C.)850885866864CTE (10⁷Â° C.^âˆ’1)9279.790.595.1Density (g/cm³)2.4112.3752.412.432E Mod (Mpsi)9.4059.3689.4899.695G Mod (Mpsi)3.833.8143.8773.946Î½ (Poisson's ratio)0.2280.2280.2240.228Indentation Threshold (kgf)2542.537.527.54015CS (MPa)¹859.86804.16929.92885.30905.74CS (MPa)¹(SOC corrected)819.03798.84914.11848.48889.52DOL (Î¼m)¹57.6057.3857.2657.2057.1156.82CS (MPa)²1035.22950.121059.78989.531074.72CS (MPa)²(SOC corrected)986.07902.291041.76948.371055.47DOL (Î¼m)²44.4044.0042.7045.2447.5744.47Glass (mol %)737475767778SiO₂65.7664.1864.5365.7757.4261.99Al₂O₃13.8714.0113.9913.2118.5914.65B₂O₃5.156.236.607.045.356.05Na₂O13.9113.9013.7113.8417.1714.67K₂O0.111.490.500.010.260.52MgO1.080.010.490.011.060.02CaO0.030.060.060.010.050.08ZnO0.00P₂O₅SnO₂0.070.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.151.380.220.65âˆ’1.160.55[B₂O₃] âˆ’ ([Na₂O] +5.004.866.386.406.515.50[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)589557570553607610Anneal Pt. (Â° C.)644607623606661666Soft Pt. (Â° C.)918847890873917919CTE (10⁷Â° C.^âˆ’1)77.284.280.477.286.880.5Density (g/cm³)2.3892.4022.3832.3752.4292.44E Mod (Mpsi)9.6759.8099.4579.47710.0099.805G Mod (Mpsi)3.9934.0443.8913.874.13.983Î½ (Poisson's ratio)0.2120.2130.2150.2250.2210.231Indentation Threshold (kgf)5027.532.522.5>2513.75CS (MPa)¹827.18722.71765.12735.801042.17928.11CS (MPa)¹(SOC corrected)789.68701.96718.791030.82DOL (Î¼m)¹56.8256.7556.7356.6556.6356.53CS (MPa)²978.88863.59897.56843.061188.561121.22CS (MPa)²(SOC corrected)934.50838.80843.201175.63DOL (Î¼m)²42.6546.2244.1742.4243.4941.84Glass (mol %)798081828384SiO₂54.3762.3664.2960.9260.0864.56Al₂O₃19.1915.5913.9516.4716.6213.90B₂O₃6.985.797.655.836.347.03Na₂O18.1916.0713.9016.4016.8014.31K₂O0.990.030.010.070.070.01MgO0.020.040.010.290.080.01CaO0.120.020.060.030.030.06ZnOP₂O₅SnO₂0.100.100.100.080.080.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.000.50âˆ’0.040.000.250.41[B₂O₃] âˆ’ ([Na₂O] +6.995.297.695.836.096.62[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)561571.5756572573.7447564.3761574Anneal Pt. (Â° C.)613623.9441629628.2527618.0616627Soft Pt. (Â° C.)862899891CTE (10⁷Â° C.^âˆ’1)96.278.578.9Density (g/cm³)2.4282.3672.378E Mod (Mpsi)9.5739.2889.373G Mod (Mpsi)3.8963.7523.832Î½ (Poisson's ratio)0.2290.2380.223Indentation Threshold (kgf)2537.532.542.537.542.5CS (MPa)¹948.59878.64774.46782.10CS (MPa)¹(SOC corrected)929.87852.11696.88903.79853.09723.20DOL (Î¼m)¹56.4355.8755.7055.3455.2755.22CS (MPa)²1072.69992.79903.52918.78CS (MPa)²(SOC corrected)1051.53962.82813.011004.83974.01849.58DOL (Î¼m)²47.4343.9842.0643.0444.0341.80Glass (mol %)798081828384SiO₂54.3762.3664.2960.9260.0864.56Al₂O₃19.1915.5913.9516.4716.6213.90B₂O₃6.985.797.655.836.347.03Na₂O18.1916.0713.9016.4016.8014.31K₂O0.990.030.010.070.070.01MgO0.020.040.010.290.080.01CaO0.120.020.060.030.030.06ZnOP₂O₅SnO₂0.100.100.100.080.080.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.000.50âˆ’0.040.000.250.41[B₂O₃] âˆ’ ([Na₂O] +6.995.297.695.836.096.62[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)561571.5756572573.7447564.3761574Anneal Pt. (Â° C.)613623.9441629628.2527618.0616627Soft Pt. (Â° C.)862899891CTE (10⁷Â° C.^âˆ’1)96.278.578.9Density (g/cm³)2.4282.3672.378E Mod (Mpsi)9.5739.2889.373G Mod (Mpsi)3.8963.7523.832Î½ (Poisson's ratio)0.2290.2380.223Indentation Threshold (kgf)2537.532.542.537.542.5CS (MPa)¹948.59878.64774.46782.10CS (MPa)¹(SOC corrected)929.87852.11696.88903.79853.09723.20DOL (Î¼m)¹56.4355.8755.7055.3455.2755.22CS (MPa)²1072.69992.79903.52918.78CS (MPa)²(SOC corrected)1051.53962.82813.011004.83974.01849.58DOL (Î¼m)²47.4343.9842.0643.0444.0341.80Glass (mol %)858687888990SiO₂55.1164.3164.3464.3465.7163.41Al₂O₃18.4113.6814.7214.0013.9013.96B₂O₃7.587.016.185.995.157.07Na₂O18.4714.2913.4314.0613.4213.89K₂O0.250.500.200.510.111.49MgO0.010.021.010.011.600.01CaO0.040.060.020.060.040.06ZnO0.000.000.91P₂O₅SnO₂0.100.100.070.100.070.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.311.11âˆ’1.090.57âˆ’0.371.42[B₂O₃] âˆ’ ([Na₂O] +7.285.907.285.425.525.65[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)562545.1596568594549Anneal Pt. (Â° C.)611594.9653623649596Soft Pt. (Â° C.)857929890928823CTE (10⁷Â° C.^âˆ’1)93.27679.875.186.2Density (g/cm³)2.4212.3812.4042.3882.4E Mod (Mpsi)9.4689.5939.57610.0059.712G Mod (Mpsi)3.8463.913.9524.1233.993Î½ (Poisson's ratio)0.2310.2270.2110.2130.216Indentation Threshold (kgf)27.527.532.532.542.527.5CS (MPa)¹871.28824.73807.70826.35741.59CS (MPa)¹(SOC corrected)715.55773.18782.00788.89717.44DOL (Î¼m)¹55.0655.0054.7454.7454.5154.45CS (MPa)²1067.00960.72950.41961.11847.99CS (MPa)²(SOC corrected)855.74900.68920.17917.54820.39DOL (Î¼m)²43.7841.9741.2741.7140.9741.98Glass (mol %)919293949596SiO₂60.0464.5961.9164.2664.7770.65Al₂O₃16.5413.8813.9413.9613.8712.35B₂O₃6.437.026.077.146.513.95Na₂O16.7113.8015.4613.9314.1412.35K₂O0.070.500.520.520.520.51MgO0.110.020.020.010.010.02CaO0.030.060.080.060.060.07ZnOP₂O₅SnO₂0.070.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.240.412.030.490.780.51[B₂O₃] âˆ’ ([Na₂O] +6.196.614.046.655.733.44[K₂0] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)566.277557593565567582Anneal Pt. (Â° C.)619.0794610646617617640Soft Pt. (Â° C.)879883885874869949CTE (10⁷Â° C.^âˆ’1)89.179.484.48180.571.2Density (g/cm³)2.3992.3792.4492.3792.3882.374E Mod (Mpsi)9.6079.4519.8429.4439.5319.784G Mod (Mpsi)3.9253.8644.023.8583.9414.047Î½ (Poisson's ratio)0.2240.2230.2240.2240.2090.209Indentation Threshold (kgf)37.53511.7542.537.522.5CS (MPa)¹782.47931.17786.03782.17754.58CS (MPa)¹(SOC corrected)853.81724.59737.12749.86DOL (Î¼m)¹54.4554.3354.2154.1554.0253.97CS (MPa)²871.701147.76889.71888.55861.31CS (MPa)²(SOC corrected)971.19807.23834.35851.85DOL (Î¼m)²43.9141.5739.1344.7342.9649.11Glass (mol %)979899100101102SiO₂64.3262.7764.7559.9954.5864.48Al₂O₃14.0014.5513.9116.5518.3814.03B₂O₃6.157.117.146.448.145.97Na₂O13.8214.8713.9916.8518.4713.81K₂O0.510.510.010.070.260.50MgO1.010.030.010.070.011.03CaO0.060.070.060.030.050.07ZnO0.000.00P₂O₅SnO₂0.100.090.100.080.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.330.820.090.370.340.27[B₂O₃] âˆ’ ([Na₂O] +5.836.297.056.077.805.70[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)572546.8577560.9948559572Anneal Pt. (Â° C.)626597.4631613.35608625Soft Pt. (Â° C.)889854.5913872.8846893CTE (10⁷Â° C.^âˆ’1)79.478.18994.479.6Density (g/cm³)2.3912.3842.3712.42.422.389E Mod (Mpsi)9.5799.2649.569.4589.645G Mod (Mpsi)3.9553.7913.8913.8363.938Î½ (Poisson's ratio)0.2110.2220.2280.2330.225Indentation Threshold (kgf)37.53237.542.542.540CS (MPa)¹769.54801.86861.80830.03CS (MPa)¹(SOC corrected)733.99748.04730.95838.22799.49DOL (Î¼m)¹53.9553.9053.7553.5853.5553.55CS (MPa)²905.70918.131080.27939.81CS (MPa)²(SOC corrected)863.86851.32836.94967.98905.22DOL (Î¼m)²40.2443.6443.4142.7742.3640.85Glass (mol %)103104105106107108SiO₂65.0164.0264.3764.2765.5965.08Al₂O₃14.2313.7013.9613.9413.9013.22B₂O₃5.756.967.027.045.126.31Na₂O14.7514.6313.9713.1215.1513.19K₂O0.080.500.010.520.110.51MgO0.040.020.010.010.011.50CaO0.030.060.060.060.030.08ZnO0.480.92P₂O₅SnO₂0.100.100.100.100.070.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.601.430.02âˆ’0.301.360.48[B₂O₃] âˆ’ ([Na₂O] +5.155.537.007.343.765.83[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)566.5828543.7571569571550Anneal Pt. (Â° C.)620.1886591.9627624621603Soft Pt. (Â° C.)895907859CTE (10⁷Â° C.^âˆ’1)7675.382.377Density (g/cm³)2.3892.3812.392.4032.39E Mod (Mpsi)9.3229.469.8689.746G Mod (Mpsi)3.8143.8494.0743.99Î½ (Poisson's ratio)0.2220.2290.2110.221Indentation Threshold (kgf)37.5(Ann)22.527.532.517.537.5CS (MPa)¹816.21809.37783.77755.16751.10CS (MPa)¹(SOC corrected)780.61706.79752.35725.48737.30DOL (Î¼m)¹53.4753.2953.2653.1253.0653.00CS (MPa)²930.06943.17950.90CS (MPa)²(SOC corrected)889.50827.26876.73928.42DOL (Î¼m)²42.9241.7739.9941.16Glass (mol %)109110111112113114SiO₂64.4863.8063.2164.4766.6562.81Al₂O₃13.9613.9513.9914.0113.0314.61B₂O₃6.046.588.147.015.696.94Na₂O13.2114.9713.9613.7812.3214.95K₂O0.100.500.500.001.010.51MgO2.100.020.020.531.060.02CaO0.030.060.060.070.130.06ZnO0.00P₂O₅SnO₂0.070.100.100.100.100.09[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’0.641.520.47âˆ’0.220.300.85[B₂O₃] âˆ’ ([Na₂O] +6.695.067.677.245.396.08[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)583546556574559.3548.2Anneal Pt. (Â° C.)637594608630614.1598.5Soft Pt. (Â° C.)899856906899.7CTE (10⁷Â° C.^âˆ’1)74.780.675.775.8Density (g/cm³)2.3872.3752.3722.375E Mod (Mpsi)9.7469.2769.305G Mod (Mpsi)3.9573.8073.825Î½ (Poisson's ratio)0.2320.2180.216Indentation Threshold (kgf)42.522.537.542.537.535CS (MPa)¹811.03748.11812.57CS (MPa)¹(SOC corrected)710.94685.39757.32741.11752.91DOL (Î¼m)¹52.8952.7952.7752.7452.7352.66CS (MPa)²953.71876.23926.46CS (MPa)²(SOC corrected)833.02802.77863.47804.99856.01DOL (Î¼m)²37.3745.0041.6241.2143.3544.04Glass (mol %)115116117118119120SiO₂53.4664.5364.7664.2165.1366.06Al₂O₃18.4213.9113.9714.6813.1013.66B₂O₃9.136.615.575.736.075.74Na₂O18.5613.7213.5613.5112.9714.29K₂O0.260.100.500.200.510.07MgO0.011.021.451.542.030.04CaO0.050.020.060.030.080.03ZnO0.000.000.000.00P₂O₅SnO₂0.100.070.100.070.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.39âˆ’0.090.09âˆ’0.970.380.70[B₂O₃] âˆ’ ([Na₂O] +8.746.705.486.715.705.04[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)556578577598553563.1957Anneal Pt. (Â° C.)606632632654606616.3392Soft Pt. (Â° C.)828906895926CTE (10⁷Â° C.^âˆ’1)93.176.67976.876.7Density (g/cm³)2.4142.382.3952.3882.391E Mod (Mpsi)9.2929.5449.6059.6649.822G Mod (Mpsi)3.7673.9024.0063.9754.02Î½ (Poisson's ratio)0.2330.2230.1990.2150.222Indentation Threshold (kgf)42.547.542.537.537.537.5(Ann)CS (MPa)¹824.51820.08791.46840.55740.40789.01CS (MPa)¹(SOC corrected)762.22795.76753.01DOL (Î¼m)¹52.6552.6252.5752.4752.4751.98CS (MPa)²1001.44966.08900.76974.09905.41CS (MPa)²(SOC corrected)867.48922.18864.11DOL (Î¼m)²41.7440.4741.5240.1541.55Glass (mol %)121122123124125126SiO₂67.6362.1464.5366.4466.4566.42Al₂O₃12.8415.5813.9813.4613.1013.04B₂O₃6.035.505.065.155.115.11Na₂O12.8115.7613.7412.6313.0013.10K₂O0.510.060.510.200.200.20MgO0.010.922.002.012.012.01CaO0.070.040.060.030.030.03ZnO0.000.000.000.00P₂O₅SnO₂0.100.080.100.070.070.07[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.480.240.28âˆ’0.630.100.26[B₂O₃] âˆ’ ([Na₂O] +5.545.254.785.785.014.85[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)558567.7924581597587585Anneal Pt. (Â° C.)612620.85634654642639Soft Pt. (Â° C.)888885902927911909CTE (10⁷Â° C.^âˆ’1)76.784.879.773.27575.9Density (g/cm³)2.3742.4012.3832.3862.387E Mod (Mpsi)9.5449.7039.7769.6989.7649.799G Mod (Mpsi)3.9423.9674.0424.0384.0134.029Î½ (Poisson's ratio)0.2110.2230.2090.2010.2160.216Indentation Threshold (kgf)17.537.535354040CS (MPa)¹804.54796.84807.95802.46799.16CS (MPa)¹(SOC corrected)869.82776.81772.02766.77764.54DOL (Î¼m)¹51.8251.7151.6351.5951.5951.32CS (MPa)²873.09914.88926.42935.89936.31CS (MPa)²(SOC corrected)978.41891.88885.22894.27895.75DOL (Î¼m)²42.0240.6240.0739.9639.9040.19Glass (mol %)127128129130131132SiO₂65.1764.5765.2466.4464.3367.77Al₂O₃13.4014.0312.9113.6914.0113.01B₂O₃6.567.005.475.154.583.49Na₂O12.7712.7112.6712.3713.8212.74K₂O1.010.490.510.200.510.10MgO0.871.013.012.032.572.76CaO0.120.070.090.020.060.04ZnO0.000.00P₂O₅SnO₂0.100.100.100.070.100.07[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.38âˆ’0.830.27âˆ’1.120.33âˆ’0.17[B₂O₃] âˆ’ ([Na₂O] +6.177.835.206.284.243.66[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)549.7576561604588604Anneal Pt. (Â° C.)603.3631613661640660Soft Pt. (Â° C.)878.4913939899942CTE (10⁷Â° C.^âˆ’1)74.974.771.278.273.9Density (g/cm³)2.3752.3722.3972.3822.4072.393E Mod (Mpsi)9.4259.9649.8039.8859.945G Mod (Mpsi)3.8514.0774.0384.0894.118Î½ (Poisson's ratio)0.2240.2220.2140.2090.208Indentation Threshold (kgf)37.53537.542.53522.5CS (MPa)¹792.11732.63801.36806.89825.18CS (MPa)¹(SOC corrected)712.77728.85710.62762.74794.90811.15DOL (Î¼m)¹51.2751.0851.0350.7450.4150.38CS (MPa)²899.49920.82928.73940.49CS (MPa)²(SOC corrected)789.12827.65876.44914.92924.50DOL (Î¼m)²39.3540.2938.9539.3438.92Glass (mol %)133134135136137138SiO₂64.4656.1763.3965.7463.3965.08Al₂O₃13.9616.6414.0013.8714.0412.96B₂O₃6.0110.146.915.087.025.78Na₂O14.8615.7714.0812.9413.8413.00K₂O0.510.980.510.110.500.51MgO0.010.050.012.131.032.49CaO0.060.130.060.040.070.09ZnO0.92P₂O₅SnO₂0.100.100.100.070.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.420.120.60âˆ’0.820.290.55[B₂O₃] âˆ’ ([Na₂O] +4.5910.026.315.906.735.23[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)562535555597562554Anneal Pt. (Â° C.)611584606653614607Soft Pt. (Â° C.)852821861928875CTE (10⁷Â° C.^âˆ’1)82.489.179.572.380.876.8Density (g/cm³)2.4042.3922.4012.3882.3842.396E Mod (Mpsi)9.8129.2339.4979.8359.5469.897G Mod (Mpsi)4.0333.723.9034.0333.8974.051Î½ (Poisson's ratio)0.2160.2410.2170.2190.2250.222Indentation Threshold (kgf)17.527.532.532.542.537.5CS (MPa)¹769.17753.37789.68815.47801.66752.16CS (MPa)¹(SOC corrected)750.06697.75758.32779.91773.92730.45DOL¹(Î¼m)50.3450.1950.0649.9149.6649.62CS (MPa)²905.17926.36930.69931.65927.02CS (MPa)²(SOC corrected)882.69857.96893.73891.02894.94DOL (Î¼m)²39.3739.8738.2838.8038.61Glass (mol %)139140141142143144SiO₂64.8561.7964.0562.8462.5465.69Al₂O₃13.0116.4714.2413.9713.8913.68B₂O₃6.815.045.918.378.836.28Na₂O13.0916.0012.0011.1211.0613.90K₂O0.510.513.323.233.220.25MgO1.530.020.020.020.020.02CaO0.080.070.360.350.350.05ZnOP₂O₅SnO₂0.100.100.100.100.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.590.041.080.390.380.47[B₂O₃] âˆ’ ([Na₂O] +6.224.994.837.998.445.81[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)547586.1542525521585Anneal Pt. (Â° C.)599643.6593578573641Soft Pt. (Â° C.)857926.5841834826925CTE (10⁷Â° C.^âˆ’1)76.48885.283.678.4Density (g/cm³)2.3882.4012.4082.382.3772.372E Mod (Mpsi)9.7129.8769.3899.3499.369G Mod (Mpsi)3.9814.0743.8483.7683.854Î½ (Poisson's ratio)0.220.2120.220.2410.216Indentation Threshold (kgf)37.522.522.5(Ann)22.5(Ann)27.5(Ann)37.5CS (MPa)¹722.07CS (MPa)¹(SOC corrected)DOL (Î¼m)¹49.44CS (MPa)²849.69801.14703.76693.72930.58CS (MPa)²(SOC corrected)981.12859.49DOL (Î¼m)²36.6962.2754.0253.0750.8549.26Glass (mol %)145146147148149150SiO₂62.2163.1861.9962.3763.2462.10Al₂O₃13.8213.4513.7813.8613.4513.48B₂O₃9.329.038.878.338.939.99Na₂O11.0013.2311.7111.7513.2613.31K₂O3.200.943.193.210.940.95MgO0.010.010.020.020.010.01CaO0.340.020.340.340.020.02ZnOP₂O₅SnO₂0.100.110.100.100.120.12[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.380.711.131.110.760.78[B₂O₃] âˆ’ ([Na₂O] +8.958.327.747.238.179.21[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)518548518523550Anneal Pt. (Â° C.)570601566571602Soft Pt. (Â° C.)824850797808841CTE (10⁷Â° C.^âˆ’1)8479.785.685.279.6Density (g/cm³)2.3742.3592.3892.3932.363E Mod (Mpsi)9.2459.149.5249.596G Mod (Mpsi)3.7993.7363.9023.935Î½ (Poisson's ratio)0.2170.2230.2210.219Indentation Threshold (kgf)32.5(Ann)32(Ann)22.5(Ann)17.5(Ann)35(Ann)32.5(Ann)CS (MPa)¹CS (MPa)¹(SOC corrected)DOL (Î¼m)¹CS (MPa)²688.61861.02719.85726.49865.32820.65CS (MPa)²(SOC corrected)784.54788.46DOL (Î¼m)²48.8548.1347.9647.8047.3047.09Glass (mol %)151152153154155156SiO₂62.7064.4468.6064.2664.8864.24Al₂O₃13.9412.2712.8612.7313.7112.45B₂O₃7.8910.015.088.977.989.47Na₂O11.7912.1612.7512.9312.2712.73K₂O3.210.950.520.941.020.94MgO0.020.010.010.010.010.01CaO0.350.020.070.020.010.02ZnOP₂O₅SnO₂0.100.120.100.120.120.12[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.050.840.411.14âˆ’0.431.22[B₂O₃] âˆ’ ([Na₂O] +6.849.174.677.848.408.25[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)531536571543550540Anneal Pt. (Â° C.)579588628594609589Soft Pt. (Â° C.)808835917833897828CTE (10⁷Â° C.^âˆ’1)86.97875.776.177.6Density (g/cm³)2.3962.3462.3772.3632.3612.358E Mod (Mpsi)9.6788.9829.6549.229.14G Mod (Mpsi)3.9713.693.9873.7813.767Î½ (Poisson's ratio)0.2190.2170.2110.2190.213Indentation Threshold (kgf)22.532.532.532.532.532.5CS (MPa)¹762.53CS (MPa)¹(SOC corrected)DOL (Î¼m)¹48.26CS (MPa)²760.22715.21880.90820.69774.93789.60CS (MPa)²(SOC corrected)DOL (Î¼m)²47.0646.7646.4446.2346.1045.68Glass (mol %)157158159160161162SiO₂51.3362.3762.0855.9164.9662.21Al₂O₃20.2113.4614.3918.3714.2114.18B₂O₃7.039.789.026.626.978.97Na₂O19.1713.2613.3718.6612.7213.51K₂O0.970.951.020.260.981.01MgO1.030.010.000.020.010.01CaO0.130.020.020.050.010.02ZnO0.00P₂O₅SnO₂0.100.120.100.100.120.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]âˆ’0.070.740.000.55âˆ’0.500.33[B₂O₃] âˆ’ ([Na₂O] +7.109.049.026.077.478.64[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)564540538575567532Anneal Pt. (Â° C.)615593593626627584Soft Pt. (Â° C.)851840868866921841CTE (10⁷Â° C.^âˆ’1)97.280.681.291.577.682.2Density (g/cm³)2.4432.3592.3672.4272.3712.365E Mod (Mpsi)9.7869.1169.5579.3549.282G Mod (Mpsi)3.9453.7273.9033.8543.761Î½ (Poisson's ratio)0.240.2230.2240.2140.234Indentation Threshold (kgf)12.532.532.532.532.532.5CS (MPa)¹1020.56CS (MPa)¹(SOC corrected)977.84DOL (Î¼m)¹49.18CS (MPa)²1083.22834.56809.461069.90934.83792.98CS (MPa)²(SOC corrected)1037.89DOL (Î¼m)²45.5545.5245.3745.2445.1944.83Glass (mol %)163164165166167168SiO₂61.7465.3062.1364.4665.2962.12Al₂O₃13.7113.8714.3313.9413.9613.92B₂O₃9.296.258.136.976.259.02Na₂O11.6313.8314.3213.8714.0013.81K₂O3.170.500.980.510.241.00MgO0.020.010.010.010.010.01CaO0.340.070.020.060.060.02ZnOP₂O₅SnO₂0.100.120.100.120.120.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.090.460.970.440.290.89[B₂O₃] âˆ’ ([Na₂O] +8.195.797.166.545.968.13[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)514574536566579530Anneal Pt. (Â° C.)563628585620635581Soft Pt. (Â° C.)789894827893908824CTE (10⁷Â° C.^âˆ’1)84.479.284.279.878.782.4Density (g/cm³)2.3862.3842.392.3792.3812.377E Mod (Mpsi)9.4869.5569.4959.4549.4639.381G Mod (Mpsi)3.8813.9063.9023.8433.8733.81Î½ (Poisson's ratio)0.2220.2230.2170.230.2220.231Indentation Threshold (kgf)22.532.532.532.532.532.5CS (MPa)¹CS (MPa)¹(SOC corrected)DOL (Î¼m)¹CS (MPa)²704.31934.16845.92915.32946.70805.04CS (MPa)²(SOC corrected)875.26859.38875.65DOL (Î¼m)²44.0543.9543.7143.1542.9542.68Glass (mol %)169170171172173174SiO₂62.0964.2365.2962.1962.8364.24Al₂O₃14.1012.0113.8813.8513.1612.46B₂O₃8.5910.016.249.009.929.44Na₂O14.0911.7014.0713.8112.9812.74K₂O1.011.910.261.020.990.94MgO0.010.000.010.010.000.01CaO0.020.020.060.020.020.02ZnOP₂O₅SnO₂0.100.120.120.100.100.12[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.011.600.450.970.811.22[B₂O₃] âˆ’ ([Na₂O] +7.588.415.798.039.118.22[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)529514576526520Anneal Pt. (Â° C.)578561630575570Soft Pt. (Â° C.)808783897816808CTE (10⁷Â° C.^âˆ’1)83.477.579.58379.2Density (g/cm³)2.3872.3672.3832.3792.363E Mod (Mpsi)9.4369.3659.4259.3199.202G Mod (Mpsi)3.8843.8333.9313.8383.742Î½ (Poisson's ratio)0.2150.2220.1990.2140.23Indentation Threshold (kgf)32.532.532.532.532.532.5CS (MPa)¹CS (MPa)¹(SOC corrected)DOL (Î¼m)¹CS (MPa)²816.97649.74945.67786.16717.94818.76CS (MPa)²(SOC corrected)883.18DOL (Î¼m)²42.1842.1741.9441.8241.7441.73Glass (mol %)175176177178179180SiO₂64.3863.9365.0766.0964.4064.14Al₂O₃12.0213.8313.9213.0813.4413.42B₂O₃9.808.096.316.978.957.15Na₂O12.6913.4414.4513.1712.1314.11K₂O0.930.510.010.510.961.04MgO0.010.020.010.010.000.00CaO0.020.070.060.070.010.02ZnOP₂O₅SnO₂0.120.100.120.100.100.12[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.600.120.540.61âˆ’0.351.74[B₂O₃] âˆ’ ([Na₂O] +8.217.975.786.379.305.41[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)535541576551539539Anneal Pt. (Â° C.)583597629605595586Soft Pt. (Â° C.)807881894879878810CTE (10⁷Â° C.^âˆ’1)78.578.477.973.582.1Density (g/cm³)2.362.3682.3852.3732.3542.398E Mod (Mpsi)9.2579.2579.4329.469.0279.836G Mod (Mpsi)3.7993.7773.8873.8743.7254.031Î½ (Poisson's ratio)0.2190.2250.2130.2210.2120.22Indentation Threshold (kgf)32.5(Ann)>2532.522.535(Ann)17.5(Ann)CS (MPa)¹CS (MPa)¹(SOC corrected)DOL (Î¼m)¹CS (MPa)²788.63863.11955.90862.03763.13836.58CS (MPa)²(SOC corrected)888.56DOL (Î¼m)²41.4341.3141.1241.1240.6940.65Glass (mol %)181182183184185186SiO₂62.1361.3864.4164.6760.9865.38Al₂O₃13.5913.6412.9413.5013.8012.94B₂O₃9.509.7910.078.9710.167.10Na₂O13.6411.5811.3812.7313.9213.88K₂O1.013.151.040.021.010.51MgO0.000.020.010.010.010.01CaO0.020.340.030.010.020.06ZnOP₂O₅SnO₂0.100.100.120.080.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.061.09âˆ’0.52âˆ’0.751.131.44[B₂O₃] âˆ’ ([Na₂O] +8.448.7010.599.729.045.66[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)522512529569517554Anneal Pt. (Â° C.)571560586628565602Soft Pt. (Â° C.)799792876909786836CTE (10⁷Â° C.^âˆ’1)81.885.373.969.883.979.3Density (g/cm³)2.3752.3842.3432.3452.3752.388E Mod (Mpsi)9.3199.4728.9629.019.329.677G Mod (Mpsi)3.8193.8593.6583.6973.8043.981Î½ (Poisson's ratio)0.220.2270.2250.2190.2250.215Indentation Threshold (kgf)32.532.532.532.522.525CS (MPa)¹729.73CS (MPa)¹(SOC corrected)695.30DOL (Î¼m)¹48.21CS (MPa)²742.96716.14684.53808.33757.92857.10CS (MPa)²(SOC corrected)816.65DOL (Î¼m)²40.6540.5940.5240.4639.9839.86Glass (mol %)187188189190191192SiO₂64.4864.5662.2665.0961.2964.50Al₂O₃12.4813.1413.6813.8113.5413.00B₂O₃10.059.028.996.2410.247.98Na₂O11.8112.0513.9514.6013.7313.39K₂O1.031.091.000.011.070.99MgO0.010.010.000.010.010.01CaO0.020.010.020.060.020.01ZnOP₂O₅SnO₂0.120.120.100.120.100.12[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.370.011.260.801.261.37[B₂O₃] âˆ’ ([Na₂O] +9.689.017.735.448.986.61[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)522530527570518533Anneal Pt. (Â° C.)576586574621566582Soft Pt. (Â° C.)835867803879780819CTE (10⁷Â° C.^âˆ’1)75.576.682.278.882.179.7Density (g/cm³)2.3492.3552.3832.3882.3782.383E Mod (Mpsi)9.0079.099.6219.3559.3429.568G Mod (Mpsi)3.7133.7423.8683.8573.8093.949Î½ (Poisson's ratio)0.2130.2150.2440.2130.2260.211Indentation Threshold (kgf)32.532.517.532.532.517CS (MPa)¹CS (MPa)¹(SOC corrected)DOL (Î¼m)¹CS (MPa)²683.02755.13799.44946.67746.92792.49CS (MPa)²(SOC corrected)872.33DOL (Î¼m)²39.5339.5139.4339.3138.9938.97Glass (mol %)193194195196197198SiO₂65.4364.1164.7262.4067.6361.87Al₂O₃13.2314.7113.3313.1713.2213.30B₂O₃5.915.228.0010.403.4510.22Na₂O12.3313.5513.2612.9012.6113.46K₂O1.010.200.510.990.101.04MgO2.132.100.010.012.870.01CaO0.140.030.070.020.040.02ZnO0.00P₂O₅SnO₂0.100.070.100.100.070.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.12âˆ’0.960.440.72âˆ’0.521.20[B₂O₃] âˆ’ ([Na₂O] +5.796.187.569.683.969.02[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)557.1598539518610517Anneal Pt. (Â° C.)610.8652590568665566Soft Pt. (Â° C.)922861798935787CTE (10⁷Â° C.^âˆ’1)76.779.377.571.281.5Density (g/cm³)2.3962.372.3612.3922.373E Mod (Mpsi)9.8619.3299.1199.9699.34G Mod (Mpsi)4.0313.8193.7224.1423.799Î½ (Poisson's ratio)0.2230.2210.2250.2030.229Indentation Threshold (kgf)32.547.517.532.522.532.5CS (MPa)¹859.15829.12CS (MPa)¹(SOC corrected)739.27829.92815.28DOL (Î¼m)¹48.9547.8749.41CS (MPa)²985.85862.47722.43937.28753.27CS (MPa)²(SOC corrected)790.05952.31921.63DOL (Î¼m)²38.9638.9138.8638.7638.7338.71Glass (mol %)199200201202203204SiO₂61.9364.3564.4663.0666.8663.31Al₂O₃13.3213.4312.9912.8713.5414.01B₂O₃10.218.447.1210.013.417.11Na₂O13.3913.6313.7612.9113.4714.87K₂O1.030.021.481.020.000.51MgO0.000.010.010.012.570.01CaO0.020.010.060.020.040.06ZnOP₂O₅SnO₂0.100.100.100.100.080.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]1.100.212.251.07âˆ’0.071.37[B₂O₃] âˆ’ ([Na₂O] +9.128.234.878.943.475.74[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)518547544517596.8418557Anneal Pt. (Â° C.)566600590567651.925604Soft Pt. (Â° C.)815867803796930838CTE (10⁷Â° C.^âˆ’1)81.575.783.479.774.482.8Density (g/cm³)2.3722.3622.4052.3642.397E Mod (Mpsi)9.2529.099.8829.26110.0469.668G Mod (Mpsi)3.7873.7674.0923.7814.1153.962Î½ (Poisson's ratio)0.2220.2070.2080.2250.2210.22Indentation Threshold (kgf)32.533.522.532.517.517.5CS (MPa)¹675.85758.41CS (MPa)¹(SOC corrected)663.13873.85735.51DOL (Î¼m)¹47.6747.9747.46CS (MPa)²735.23850.10812.89739.90905.98CS (MPa)²(SOC corrected)797.59951.73878.63DOL (Î¼m)²38.5838.5138.4838.4738.3738.19Glass (mol %)205206207208209210SiO₂64.1963.9868.7367.7867.5357.08Al₂O₃12.6614.6513.2313.4613.7718.53B₂O₃10.084.653.443.463.434.99Na₂O11.8613.7112.0112.2812.6818.69K₂O1.050.210.000.100.000.49MgO0.012.682.462.792.470.01CaO0.020.030.040.040.040.07ZnO0.00P₂O₅SnO₂0.120.070.060.070.070.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.26âˆ’0.73âˆ’1.22âˆ’1.09âˆ’1.090.65[B₂O₃] âˆ’ ([Na₂O] +9.825.384.664.554.524.34[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)522602611.8241618609.9735599Anneal Pt. (Â° C.)576656669.7462674667.3236654Soft Pt. (Â° C.)846917961952961.4922CTE (10⁷Â° C.^âˆ’1)75.376.769.470.67295.3Density (g/cm³)2.3462.4032.3912.3882.429E Mod (Mpsi)8.969.99810.07610.02110.049.774G Mod (Mpsi)3.6914.0874.1544.1364.1613.949Î½ (Poisson's ratio)0.2140.2230.2130.2110.2060.237Indentation Threshold (kgf)32.542.532.522.532.512.5CS (MPa)¹871.17826.03CS (MPa)¹(SOC corrected)854.51794.15808.24842.19DOL (Î¼m)¹48.4046.1347.5847.27CS (MPa)²716.98996.31922.73CS (MPa)²(SOC corrected)977.26865.74902.86915.68DOL (Î¼m) ²38.1838.1738.0438.0238.01Glass (mol %)211212213214215216217SiO₂57.0357.0961.2061.1360.4359.3758.52Al₂O₃18.7018.6316.8616.9917.3617.5017.52B₂O₃5.035.095.165.105.065.786.63Na₂O18.5218.4715.2214.5214.4514.4214.39K₂O0.490.491.422.192.652.882.89MgO0.020.020.110.030.010.010.01CaO0.070.080.020.020.020.020.02ZnOP₂O₅SnO₂0.100.10[Na₂O] + [K₂O] âˆ’ [Al₂O₃]0.310.34âˆ’0.22âˆ’0.27âˆ’0.26âˆ’0.19âˆ’0.23[B₂O₃] âˆ’ ([Na₂O] +4.724.755.375.375.325.976.87[K₂O] âˆ’ [Al₂O₃])Strain Pt. (Â° C.)612609596594595585572Anneal Pt. (Â° C.)667664654654654641629Soft Pt. (Â° C.)927928940.1943.9940.9927.1911.7CTE (10⁷Â° C.^âˆ’1)94.587.79092.393.593.8Density (g/cm³)2.4262.4272.4122.4122.4152.4142.41E Mod (Mpsi)9.6839.6879.8079.6169.6649.6939.631G Mod (Mpsi)3.9353.9643.9844.0164.0073.9323.878Î½ (Poisson's ratio)0.230.2220.2310.1970.2060.2330.242Indentation Threshold (kgf)202527.527.527.532.527.5CS (MPa)¹CS (MPa)¹(SOC corrected)DOL (Î¼m)¹CS (MPa)²CS (MPa)²(SOC corrected)1122.4(16 hr)1093.3(16 hr)1125.701102.901066.30DOL (Î¼m)²77.1(16 hr)83.4(16 hr)61.5060.5056.40¹Glass is fusion drawn/fictivated and ion exchanged at 410Â° C. for 8 hours in KNO₃molten salt bath.²Glass annealed and ion exchanged at 410Â° C. for 8 hours in KNO₃molten salt bath.

In a first aspect a glass comprises: from about 50 mol % to about 72 mol % SiO₂; from about 12 mol % to about 22 mol % Al₂O₃; up to about 6.5 mol % B₂O₃; up to about 1 mol % P₂O₅; from about 11 mol % to about 21 mol % Na₂O; up to about 0.95 mol % K₂O; up to about 4 mol % MgO; up to about 5 mol % ZnO; and up to about 2 mol % CaO. In the glass of the first aspect Na₂O+K₂Oâˆ’Al₂O₃â‰¦2.0 mol, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>1 mol %, 24 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag, and the glass is substantially free of TiO₂.

A second aspect includes the glass of the first aspect wherein the glass is substantially free of at least one of P₂O₅and Li₂O.

A third aspect includes the glass of the second aspect wherein the glass is substantially free of Li₂O.

A fourth aspect includes the glass of the first aspect wherein 56 mol %â‰¦SiO₂+B₂O₃â‰¦75 mol %.

A fifth aspect includes the glass of the first aspect wherein 2 mol %â‰¦B₂O₃+P₂O₅â‰¦7.5 mol %.

A sixth aspect includes the glass of the first aspect wherein the glass is ion exchanged and has a Vickers crack indentation threshold of at least about 9.5 kgf.

A seventh aspect includes the glass of the sixth aspect wherein the glass has a layer under compressive stress CS of greater than about 500 MPa, the layer extending from a surface of the glass to a depth of layer DOL, wherein CSÂ·DOL=44000 MPaÂ·Î¼m.

An eighth aspect includes the glass of the sixth aspect wherein the glass has a compressive stress of greater than about 800 MPa and a depth of layer of at least about 40 Î¼m, and has been ion exchanged for less than about four hours.

A ninth aspect includes the glass of the sixth aspect wherein the glass has a compressive stress of greater than about 800 MPa and a depth of layer of at least about 52 Î¼m, and has been ion exchanged for less than about eight hours.

A tenth aspect includes the glass of the sixth aspect The glass of claim 6, wherein the glass has a compressive stress of greater than about 800 MPa and a depth of layer of at least about 30 Î¼m, and has been ion exchanged for less than about two hours.

An eleventh aspect includes the glass of the first aspect wherein the glass is substantially free of As₂O₃and Sb₂O₅.

A twelfth aspect includes the glass of the first aspect wherein the glass further comprises at least one fining agent.

A thirteenth aspect includes the glass of the twelfth aspect wherein the at least one fining agent comprises at least one of SnO₂, CeO₂, As₂O₃, Sb₂O₅, Cl^âˆ’, and F^âˆ’.

A fourteenth aspect includes the glass of the thirteenth aspect wherein the at least one fining agent comprises at least one of up to about 0.5 mol % SnO₂, up to about 0.5 mol % As₂O₃, and up to about 0.5 mol % Sb₂O₃.

A fifteenth aspect includes the glass of the first aspect wherein the glass comprises: from about 55 mol % to about 62 mol % SiO₂; from about 16 mol % to about 20 mol % Al₂O₃; from about 2 mol % to about 6.5 mol % B₂O₃; up to about 1 mol % P₂O₅; from about 14 mol % to about 18 mol % Na₂O; from about 0.2 mol % to about 0.75 mol % K₂O; up to about 0.5 mol % MgO; up to about 0.5 mol % ZnO; and up to about 0.5 mol % CaO.

A sixteenth aspect includes the glass of the fifteenth aspect wherein Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol %.

A seventeenth aspect includes the glass of the fifteenth aspect wherein B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %.

An eighteenth aspect includes the glass of the fifteenth aspect wherein the glass comprises from about 4 mol % to about 6.5 mol % B₂O₃.

A nineteenth aspect includes the glass of the fifteenth aspect wherein the glass has a liquidus viscosity of at least 100 kpoise.

A twentieth aspect includes the glass of the nineteenth aspect wherein the glass is down-drawable.

In a twenty-first aspect a glass comprises: from about 55 mol % to about 62 mol % SiO₂; from about 16 mol % to about 20 mol % Al₂O₃; from about 4 mol % to about 6.5 mol % B₂O₃; from about 14 mol % to about 18 mol % Na₂O; from about 0.2 mol % to about 0.75 mol % K₂O; up to about 0.5 mol % MgO; up to about 0.5 mol % ZnO; and up to about 0.5 mol % CaO. In the glass of the twenty-first aspect the glass is substantially free of P₂O₅, Na₂O+K₂Oâˆ’Al₂O₃â‰¦0.5 mol %, B₂O₃âˆ’(Na₂O+K₂Oâˆ’Al₂O₃)>4 mol %, 28 mol %â‰¦RAlO₄â‰¦45 mol %, where R is at least one of Na, K, and Ag, and the glass is substantially free of TiO₂.

A twenty-second aspect includes the glass of the twenty-first aspect wherein the glass is substantially free of Li₂O.

A twenty-third aspect includes the glass of the twenty-first aspect wherein 56 mol %â‰¦SiO₂+B₂O₃â‰¦70 mol %.

A twenty-fourth aspect includes the glass of the twenty-first aspect wherein 0 mol %â‰¦Î£[Râ€²O]â‰¦0.5 mol %, where Râ€² is at least one of Ca, Mg, and Zn.

A twenty-fifth aspect includes the glass of the twenty-first aspect wherein K₂Oâ‰¦0.25(Na₂O+K₂O).

A twenty-sixth aspect includes the glass of the twenty-first aspect wherein the glass is substantially free of As₂O₃and Sb₂O₃.

A twenty-seventh aspect includes the glass of the twenty-first aspect wherein the glass further comprises at least one fining agent, the fining agent comprising at least one of SnO₂, CeO₂, As₂O₃, and Sb₂O₅, Cl^âˆ’, and F^âˆ’.

A twenty-eighth aspect includes the glass of the twenty-seventh aspect wherein the at least one fining agent comprises at least one of up to about 0.5 mol % SnO₂, up to about 0.5 mol % As₂O₃, and up to about 0.5 mol % Sb₂O₃.

A twenty-ninth aspect includes the glass of the twenty-first aspect wherein the glass has a liquidus viscosity of at least 100 kpoise.

A thirtieth aspect includes the glass of the twenty-ninth aspect wherein the glass is down-drawable.

A thirty-first aspect includes the glass of the twenty-first aspect wherein the glass is ion exchanged and has a Vickers crack indentation threshold of at least about 9.5 kgf.

A thirty-second aspect includes the glass of the thirty-first aspect wherein the glass has a layer under compressive stress CS of greater than 500 MPa, the layer extending from a surface of the glass to a depth of layer DOL, wherein CSÂ·DOL=44000 MPaÂ·Î¼m.

A thirty-third aspect includes the glass of the thirty-first aspect wherein the glass has a compressive stress of greater than about 800 MPa and a depth of layer of at least about 40 Î¼m, and has been ion exchanged for less than about four hours.

A thirty-fourth aspect includes the glass of the thirty-first aspect wherein the glass has a compressive stress of greater than about 800 MPa and a depth of layer of at least about 52 Î¼m, and has been ion exchanged for less than about eight hours.

A thirty-fifth aspect includes the glass of the thirty-first aspect wherein the glass has a compressive stress of greater than about 800 MPa and a depth of layer of at least about 30 Î¼m, and has been ion exchanged for less than about two hours.

In a thirty-sixth aspect a method of ion exchanging a glass comprises ion exchanging an alkali aluminosilicate glass for up to about eight hours in an ion exchange bath at a temperature of about 410Â° C. or less, the ion exchange bath comprising a potassium salt and the alkali aluminosilicate glass comprising: from about 50 mol % to about 72 mol % SiO₂; from about 12 mol % to about 22 mol % Al₂O₃; up to about 6.5 mol % B₂O₃; up to about 1 mol % P₂O₅; from about 11 mol % to about 21 mol % Na₂O; up to about 0.95 mol % K₂O; up to about 4 mol % MgO; up to about 5 mol % ZnO; and up to about 1 mol % CaO. The ion exchanged alkali aluminosilicate glass has a compressive layer extending from a surface to a depth of layer DOL, the compressive layer having a compressive stress CS of at least 500 MPa, and the glass is substantially free of TiO₂.

A thirty-seventh aspect includes the glass of the thirty-sixth aspect wherein CSÂ·DOL=44000 MPaÂ·Î¼m.

A thirty-eighth aspect includes the glass of the thirty-sixth aspect wherein the glass is ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 52 Î¼m within eight hours ion exchange time.

A thirty-ninth aspect includes the glass of the thirty-sixth aspect wherein the glass is ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 40 Î¼m within four hours ion exchange time.

A fortieth aspect includes the glass of the thirty-sixth aspect wherein the glass is ion exchanged to achieve a compressive stress of at least about 800 MPa and a depth of layer of at least about 30 Î¼m within two hours ion exchange time.

While typical embodiments have been set forth for the purpose of illustration, the foregoing description should not be deemed to be a limitation on the scope of the disclosure or appended claims. Accordingly, various modifications, adaptations, and alternatives may occur to one skilled in the art without departing from the spirit and scope of the present disclosure or appended claims.