Reduced optical transmittance glasses for emissive displays

Abstract

Glass is disclosed that can be used to produce glass articles, such as glass substrates for flat panel display devices. The glass may be substantially alkali-free. The glasses are doped with one or more transition metals (e.g., Ni, Co) and exhibit reduced optical transmittance to suppress light leakage from display devices and / or improve contrast. The display device may be a bottom emission display device or a top emission display device. The display device may be a tiled display device. The glasses disclosed herein may be used, for example, as a backplane having a plurality of display substrates disposed thereon, a display substrate (e.g., a backplane) having a plurality of light emitters disposed thereon, a glass cover, or a combination thereof.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of priority under 35 U.S.C.§119 to U.S. Application Serial No. 18 / 524,762, filed November 30, 2023, the content of which is incorporated herein by reference in its entirety and made a part hereof. Technical field

[0003] Embodiments of the present disclosure relate to glass articles, and more particularly, to glass substrates suitable for emissive display devices, where the glass substrates exhibit a reduced transmittance. Background art

[0004] Although there is a great need for emissive displays, such as micro - LED (μLED) displays and organic light - emitting diode (OLED) displays, the large - scale production of such displays is plagued by low yields and high costs, and poses technical challenges for emerging high - resolution displays.

[0005] One challenge involves the manufacture of large - area emissive displays. A widely accepted and cost - effective method of producing a large - area emissive display is to arrange multiple small displays (tiles) to form a large - area display. However, such designs may exhibit light leakage at the edges of individual tiles. This light leakage may appear as bright lines at the seams between tiles to an observer. There are several existing methods to mitigate seam visibility - one is edge coating. Another is the lamination of a low - transmittance film. For edge coating, coating accuracy and reliability are challenging. For the lamination of a low - transmittance film, the main problems are reliability, including mechanical and environmental durability.

[0006] Another problem that emissive displays may experience is the degradation of the contrast ratio. Due to the light confinement of the light guide formed by the encapsulation layers of the emissive display, such as an optically transparent adhesive layer and a cover plate (e.g., a glass cover plate), light emitted from one pixel emitter may leak into adjacent pixels through the light guide. This may result in a reduced contrast of the display and cause a "halo" effect. Summary of the invention

[0007] In a first aspect, a glass article including a glass substrate is disclosed, the glass substrate including an average optical transmittance equal to or less than about 91% in the wavelength range from 450 nm to 650 nm, and a washout index WI equal to or less than about 0.165 when measured by the WI measurement method.

[0008] In a second aspect, the average optical transmittance of the glass substrate of the first aspect or the second aspect may be in the range from about 60% to about 90%.

[0009] In a third aspect, the glass of the glass substrate of the first aspect may be alkali-free.

[0010] In a fourth aspect, the annealing point of the glass of the third aspect may be greater than about 700 °C.

[0011] In a fifth aspect, the liquidus temperature of the glass of any one of the third aspect to the fourth aspect may be greater than about 1000 °C.

[0012] In a sixth aspect, the liquidus temperature of the fifth aspect is in the range from about 1000 °C to about 1300 °C.

[0013] In a seventh aspect, in the temperature range of 0 °C to 300 °C, the thermal expansion coefficient of the glass of any one of the third aspect to the sixth aspect may be in the range from about 29×10 -7 to about 40×10 -7 .

[0014] In an eighth aspect, the density of the glass of any one of the third aspect to the seventh aspect may be equal to or less than about 2.65 g / cc 3 .

[0015] In a ninth aspect, the glass article of any one of the first aspect to the eighth aspect may include a display device.

[0016] In a tenth aspect, the glass substrate of the ninth aspect includes a cover substrate of a display panel of the display device.

[0017] In an eleventh aspect, the brightness ratio of the display device of any one of the ninth aspect to the tenth aspect may be equal to or less than about 91%.

[0018] In a twelfth aspect, the composition of the glass of any one of the second aspect to the eleventh aspect may include, in terms of mole percentage based on oxides:

[0019] SiO 2 61–74;

[0020] Al 2 O 3 9–14;

[0021] B 2 O 3 0–12;

[0022] MgO 0–9;

[0023] CaO 3.5–12;

[0024] SrO 0–5;

[0025] BaO 0–5;

[0026] SnO 2 0–0.15;

[0027] NiO 0.025–0.13;

[0028] Co 3 O 4 0.005–0.04, and

[0029] where (MgO + CaO + SrO + BaO) / Al 2 O 3 is equal to or greater than about 1.

[0030] In a thirteenth aspect, the glass of the twelfth aspect may include:

[0031] NiO 0.055–0.065; and

[0032] Co 3 O 4 0.011–0.013.

[0033] In a fourteenth aspect, the glass of the twelfth aspect or the thirteenth aspect may include:

[0034] NiO 0.055–0.065; and

[0035] Co 3 O 4 0.011–0.013.

[0036] In a fifteenth aspect, a display device including a display panel is disclosed, the display panel including a plurality of light emitters disposed on a bottom substrate, and a glass cover substrate disposed on the bottom substrate and attached thereto through an adhesive layer, the glass cover substrate including an average transmittance equal to or less than about 91% in a wavelength range from 450 nm to 650 nm. The brightness ratio of the display device may be equal to or less than about 91%.

[0037] In a sixteenth aspect, when measured by the WI measurement method, the erosion index WI of the glass cover substrate of the fifteenth aspect is equal to or less than about 0.165.

[0038] In a seventeenth aspect, the glass cover substrate of any one of the fifteenth aspect or the sixteenth aspect may include glass, the glass including, in terms of mole percentage based on oxides:

[0039] SiO 261–74;

[0040] Al 2 O 3 9–14;

[0041] B 2 O 3 0–12;

[0042] MgO 0–9;

[0043] CaO 3.5–12;

[0044] SrO 0–5;

[0045] BaO 0–5;

[0046] SnO 2 0–0.15;

[0047] NiO 0.025–0.13;

[0048] Co 3 O 4 0.005–0.04, and

[0049] where (MgO + CaO + SrO + BaO) / Al 2 O 3 is equal to or greater than about 1.

[0050] In an eighteenth aspect, the glass of the seventeenth aspect may include:

[0051] NiO 0.055–0.065; and

[0052] Co 3 O 4 0.011–0.013.

[0053] In a nineteenth aspect, the glass of the seventeenth aspect or the eighteenth aspect may include:

[0054] NiO 0.077–0.128; and

[0055] Co 3 O 4 0.025–0.037.

[0056] In a twentieth aspect, the annealing point of the glass of any one of the seventeenth aspect to the nineteenth aspect may be greater than about 700 °C.

[0057] In a twenty-first aspect, the liquidus temperature of the glass of any one of the seventeenth aspect to the twentieth aspect may be in the range from about 1000 °C to about 1300 °C.

[0058] In a twenty-second aspect, in a temperature range from 0 °C to 300 °C, the thermal expansion coefficient of the glass of any one of the seventeenth aspect to the twenty-first aspect may be in the range from about 29×10 -7 to about 40×10 -7 .

[0059] In a twenty-third aspect, the density of the glass of any one of the seventeenth aspect to the twenty-second aspect may be equal to or less than about 2.65 g / cc 3 .

[0060] In a twenty-fourth aspect, in the wavelength range from 450 nm to 650 nm, the average transmittance of the glass of any one of the fifteenth aspect to the twenty-third aspect may be equal to or less than about 90%.

[0061] In a twenty-fifth aspect, in the wavelength range from 450 nm to 650 nm, the average transmittance of the glass of any one of the fifteenth aspect to the twenty-third aspect may be equal to or less than about 85%.

[0062] In a twenty-sixth aspect, in the wavelength range from 450 nm to 650 nm, the average transmittance of the glass of any one of the fifteenth aspect to the twenty-third aspect may be equal to or less than about 80%.

[0063] In a twenty-seventh aspect, in the wavelength range from 450 nm to 650 nm, the average transmittance of the glass of any one of the fifteenth aspect to the twenty-sixth aspect may be in the range from about 50% to about 91%.

[0064] Additional embodiments of the present disclosure relate to an object including glass produced by a down-draw sheet manufacturing process. Other embodiments relate to glass produced by a melting process or a variant thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The drawings incorporated in and forming a part of this specification illustrate several embodiments described below.

[0066] Figure 1 is a top view of an exemplary bottom-emitting display device including a plurality of display tiles arranged in rows and columns;

[0067] Figure 2 is Figure 1 a cross-section of a part of the display device of

[0068] Figure 3 is Figure 2 a close-up cross-sectional view of a part of the display device of

[0069] Figure 4 Schematic diagram of a formed body for manufacturing a precision sheet in a fusion draw process;

[0070] Figure 5 is Figure 4 Cross-sectional view of the formed body; and

[0071] Figure 6 Graph of the transmission percentage of an exemplary glass composition of Table 1 measured with an optical power meter;

[0072] Figure 7 Another top view of a top-emitting tiled display including a plurality of display tiles arranged in rows and columns;

[0073] Figure 8 is Figure 7 Side cross-sectional view of the display;

[0074] Figure 9 is Figure 7 Top view of a single display tile showing a single light emitter arranged on the display tile;

[0075] Figure 10 is Figure 7 Cross-sectional view of a part of the display showing several ways in which light can leak from the edges of the individual tiles of the display;

[0076] Figure 11 is Figure 7 Cross-sectional view of a part of the display showing several additional ways in which light can leak from the edges of the individual tiles of the display;

[0077] Figure 12 is Figure 9 Side cross-sectional view of the light emitter of the display tile;

[0078] Figure 13 is Figure 9 Top view of several light emitters of the display tile showing dimensional parameters;

[0079] Figure 14 Cross-sectional side view of an exemplary display device showing edge and orthogonal (normal) light for determining the brightness ratio of the display device;

[0080] Figure 15 Graph showing the brightness ratio expressed as a percentage as a function of the transmission ratio for three thicknesses of glass substrate;

[0081] Figure 16 Schematic diagram of a measurement setup for determining the scour index of a glass substrate;

[0082] Figure 17Shows a portion of the 1951 USAF resolution test chart for determining the luminance ratio;

[0083] Figure 18 Is a graph showing the luminance ratios of three types of glass with different transmittance ratios;

[0084] Figure 19 Is a bar graph showing the erosion indices of four glass samples;

[0085] Figure 20 Is a series of schematic diagrams for manufacturing a ring-shaped FET device subjected to the experiments as described herein;

[0086] Figure 21 Is Figure 20 A top view of the ring-shaped FET device shown in;

[0087] Figure 22 Is Figure 14 - 15 A graph of the typical transfer curve (drain current as a function of gate voltage) of the ring-shaped FET of;

[0088] Figure 23 Is a chart showing the FET device cut-off current (Min(Id)) extracted from the transfer curve and plotted with different drain voltages (Vd); and

[0089] Figure 24 Is a graph of time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurements used to determine the Ni On Ni + And Co + Ion concentration depth profiles on doped Lotus

[0090] Figure 25 Is a top view of the central part of a top-emitting display device subjected to the experiments as described herein, showing a comparison between "on" state light emitters and "off" state light emitters;

[0091] Figure 26 Is showing as Figure 25 A graph of the modeled normalized average illuminance of active pixels and dark pixels as a function of the transmissivity of the cover glass of the display, where the refractive index of the OCA layer of the display is 1.49;

[0092] Figure 27 Is a graph showing the contrast ratio of the display as a function of the transmissivity of the cover glass, where the refractive index of the OCA layer of the display is 1.49;

[0093] Figure 28 Is showing as Figure 25Graph of the contrast improvement of a display, where the refractive index of the OCA layer of the display is 1.49;

[0094] Figure 29 is a graph showing the Figure 25 modeled normalized average illuminance of active pixels and dark pixels as a function of the transmissivity of the cover glass of a display, where the refractive index of the OCA layer of the display is 1.40;

[0095] Figure 30 is a graph showing the contrast of a display as a function of the transmissivity of the cover glass, where the refractive index of the OCA layer of the display is 1.49; and

[0096] Figure 31 is a graph showing the Figure 25 contrast improvement of a display as a function of the transmissivity of the cover glass, where the refractive index of the OCA layer of the display is 1.4;

[0097] Figure 32 is a graph obtained from TOF - SIMS analysis of a simulated TFT device disposed on a glass substrate, the glass substrate including the exemplary transition - metal - doped glass described herein, the glass substrate having a barrier layer disposed between the glass substrate and the simulated TFT device, the data showing that transition metals do not diffuse into the simulated TFT device under normal deposition conditions;

[0098] Figure 33 is another graph obtained from TOF - SIMS analysis of a simulated TFT device disposed on a glass substrate, the glass substrate including the exemplary transition - metal - doped glass described herein, the glass substrate having a barrier layer disposed between the glass substrate and the simulated TFT device, the data showing that transition metals do not diffuse into the simulated TFT device under normal deposition conditions; and

[0099] Figure 34 is a graph obtained from TOF - SIMS analysis of a silicon wafer heated under normal TFT deposition conditions, the silicon wafer being in close proximity to a glass substrate doped with transition - metal dopants (e.g., Ni, Co), showing a substantial lack of transition - metal dopants evaporated from the glass substrate and subsequent contamination. Detailed Description

[0100] Various disclosed embodiments may relate to specific features, elements, or steps described in connection with a particular embodiment. Although a particular feature, element, or step is described in connection with one particular embodiment, these features, elements, or steps may be interchanged or combined with alternative embodiments in various combinations or arrangements not shown.

[0101] As used herein, the terms "the", "a", or "an" mean "at least one" and shall not be limited to "only one" unless expressly stated to the contrary.

[0102] Ranges may be expressed herein as from "about" one particular value, and / or to "about" another particular value. When expressing such a range, examples include from one particular value and / or to another particular value, such as within the measurement error of such values. Similarly, when values are expressed as approximations by use of the antecedent "about", it will be understood that the particular value forms another aspect. It should also be further understood that each endpoint of a range is significant relative to the other endpoint and independent of the other endpoint.

[0103] As used herein, the terms "substantially", "essentially" and their variants are intended to mean that the described feature is equal to or approximately equal to a value or description. Additionally, "substantially similar" is intended to mean that two values are equal or approximately equal. In some embodiments, "substantially" or its variants (e.g., substantially similar) may represent values that differ from each other by within about 10%, such as within about 5% of each other, within about 2% of each other, or within about 1% of each other.

[0104] Unless otherwise expressly stated, it is in no way intended that any method described herein be construed as requiring that its steps be performed in a particular order. Accordingly, where a method claim does not actually recite an order to be followed by its steps, or where no such order is otherwise specifically set forth in the claim or the specification, this in no way implies any order.

[0105] While the transitional phrase "comprising" may be used to disclose various features, elements or steps of an embodiment, alternative embodiments, including those that may be described using the transitional phrases "consisting of" or "consisting essentially of", are implicit. Thus, for example, implicit alternative embodiments of an apparatus comprising A + B + C include embodiments where the apparatus consists of A + B + C and embodiments where the apparatus consists essentially of A + B + C.

[0106] As used herein, the transitional phrases "comprising", "including" and "having" are considered to be open-ended unless otherwise expressly stated.

[0107] For the sake of brevity, numerical ranges disclosed herein, including compositional ranges or property (performance) ranges, or a series of ranges, may be appended with the phrase "including all ranges and sub-ranges therebetween", which shall be construed to include integer or decimal sub-ranges as if expressly recited. Thus, for example, a range between 6 and 8 (units omitted) implicitly includes sub-ranges between 6.4 and 8, or between 6 and 7.2, or between 6 and 7, etc. Further, a series of ranges, such as "in the range from 6 to 11 or in the range from 6 to 8" implicitly includes the range from 7 to 10, or sub-ranges therebetween, such as 7.2 to 10.4, as if expressly recited, provided that the ranges do not exceed the minimum or maximum endpoints of the expressly recited range or series of ranges. Thus, for example, "in the range from 6 to 11 or in the range from 6 to 8" has endpoints 6 and 11.

[0108] Unless otherwise indicated, all components of the exemplary glass compositions disclosed herein are expressed in mole percent (mol%) based on oxides.

[0109] As used herein, unless otherwise expressly stated, transmittance (or transmission rate) is defined as the ratio of incident light falling on a body from a vacuum to the incident light transmitted through the body to a vacuum. The transmittance of a body can range from about 0% to about 100%, where in the range of 0%, all incident light is blocked from passing through the body, and in the range of about 100%, all incident light passes through the body.

[0110] As used herein, refractive index is defined as the ratio of the speed of light in a vacuum to the speed of light in a specified medium.

[0111] Micro-LEDs are one of several next-generation display technologies. Micro-LEDs can provide high brightness, high contrast ratio, low power consumption, and high reliability, and these properties can meet or exceed the performance of competing technologies, such as liquid crystal displays or organic light-emitting diode displays.

[0112] There is a great need for large-area displays in consumer and public information systems. However, high cost and low yield pose technical challenges to the large-scale production of such large-area displays. This is especially true for high-resolution micro-light-emitting diode (micro-LED) displays, at least due to the small size of the light emitters. One solution for manufacturing large-area displays is to tile multiple individual small displays on a substrate, thereby forming a tiled display device, where the individual small displays form tiles. These tiles can be arranged, for example, in rows and / or columns such that the size of the large-area display can be scaled based on the number of individual small displays. Although the underlying substrate for micro-LED displays can be glass or polymer, glass offers high-temperature compatibility and stable dimensions, making glass the preferred substrate material.

[0113] One persistent problem with tiled applications is light leakage at the edges of the tiles. That is, light emitted by light emitters disposed on the tiles can be redirected through the edges of the tiles and subsequently directed to an observer, e.g., by reflection within the display, such as from a bottom plate substrate on which the light emitters are mounted. Several methods have been proposed to mitigate light leakage, e.g., by coating the tile edges and / or laminating a low-transmission film to the bottom plate substrate. However, both have drawbacks. For example, the ability to precisely deposit the coating, reliability, and durability, and especially the mechanical and environmental durability of the laminated film.

[0114] Another method of suppressing light leakage from the gaps (seams) between tiles of a tiled display device disclosed herein is to reduce the brightness of the leaked light. This can be achieved by employing a glass substrate with a reduced transmittance. In other words, the glass can be intentionally doped with a material that "colors" the glass, thereby increasing the optical attenuation of the glass.

[0115] Another problem that emissive displays may experience is degradation of the contrast ratio. Encapsulation layers in emissive displays, such as plates and optical adhesive layers, are prone to forming light guides that confine and direct light. Thus, light from one pixel emitter may leak through the light guide to adjacent pixels, which results in a reduction in the display contrast, which may appear to an observer as a "halo" effect. This problem can also be solved by employing a glass substrate with a reduced transmittance.

[0116] The glass compositions disclosed herein are generally free of alkali (alkali metals). However, the glass may contain some alkali metals as contaminants. In the case of display applications, it is desirable to keep the alkali metal level below 0.1 mole percent (mol %), to avoid negative impacts on the performance of thin film transistors (TFTs) due to diffusion of alkali metal ions from the glass into the silicon of the TFTs. As used herein, "alkali-free glass" is glass with a total alkali metal concentration less than or equal to 0.1 mol %, where the total alkali metal concentration is the sum of the concentrations of Na 2 O, K 2 O, and Li 2 O.

[0117] The glass disclosed herein also relates to a semiconductor assembly including a semiconductor disposed on a glass substrate, wherein the glass substrate includes the alkali-free glass of the present disclosure. Examples of semiconductors that can be used in the above semiconductor assembly include transistors, diodes, silicon transistors, silicon diodes, and other silicon semiconductors; field effect transistors (FETs), thin film transistors (TFTs), organic light emitting diodes (OLEDs), and other light emitting diodes; and semiconductors that can be used in electro-optic (EO) applications, two-photon mixing applications, nonlinear optical (NLO) applications, electroluminescent applications, and photovoltaic and sensor applications. Such semiconductor assemblies can include sub-assemblies of larger assemblies. For example, in an embodiment, such a semiconductor assembly can include a display assembly, such as a display tile assembly, which itself can form part of a larger display device, such as a flat panel display device including a flat transparent glass substrate carrying polysilicon thin film transistors, wherein the glass substrate includes the alkali-free glass of the present disclosure.

[0118] Figures 1 to 3 are several views of an exemplary display device 10 (e.g., a large area display) that includes a plurality of display tiles 12 (small displays) disposed on a substrate 14. Figure 1 is a top view of the display device 10, showing a plurality of display tiles arranged in rows and columns on the substrate 14. Refer Figures 2 - 3 , each display tile 12 includes a transparent substrate 16 that includes a plurality of light emitters 18 disposed thereon. The transparent substrate 16 can include, for example, glass, or can include another non-conductive material, such as a polymer material. The light emitters 18 can be light emitting diodes (LEDs). For example, the light emitters 18 can be micro-LEDs, where each micro-LED can include a light emitting region having dimensions (length and / or width) in the range of about 1 micron (μm) to about 100 microns, although other dimensions, such as greater than 100 μm, can also be considered. The light emitters 18 can be bottom-emitting light emitters, where light is primarily emitted through the bottom surface of the light emitter through the substrate 16.

[0119] As Figure 3Best seen, the figure depicts a close-up view of a portion of the display device 10. The substrate 14 includes a glass substrate that includes a first major surface 20 and a second major surface 22 opposite the first major surface 20. The second major surface 22 may be parallel or substantially parallel to the first major surface 20. Two display tiles, a first display tile 12a and a second display tile 12b, are shown disposed on the first major surface 20, although more than two tiles may be disposed on the first major surface 20. A gap (seam) G separates the first display tile 12a from the second display tile 12b. As further shown, light emitted from the light emitter 18 is directed through the substrate 14. While a first portion 24 of the light travels directly through the substrate 14, a second portion 26 of the light emitted by the light emitter 18 may be directed into the gap G, and at least a portion of the light may pass through the substrate 14 and be directed outwards from the display device 10 and may be seen by an observer 28 as a bright line. To mitigate the light observed at the gap, the substrate 14 may be formed of glass that exhibits optical attenuation (e.g., percentage of transmission), which reduces the brightness of the light passing through the substrate.

[0120] As described herein, glass suitable for use as the substrate 14 includes alkali-free glass, which has a high annealing point (temperature) and a high Young's modulus, allowing the glass to have excellent dimensional stability (e.g., low shrinkage), thereby reducing variability during post-glass manufacturing processes. For example, in an embodiment, the substantially alkali-free glass may have an annealing point greater than about 700 °C.

[0121] In an embodiment, an exemplary glass may be manufactured into a glass sheet by a fusion draw process. The fusion draw process may produce an original fire-polished glass surface, reducing surface-mediated distortion of high-resolution TFT substrates and color filters. Figure 4 is a schematic view of a molten form 30 in a non-limiting fusion draw process, while Figure 5 is a cross-sectional view of the form along line 5-5. Molten glass 32 is introduced through an inlet 34 and flows along the bottom of a trough 36 formed by a weir 38 to the opposite ends of the trough 36. The molten glass overflows from the weirs 38 on both sides of the form 30 (see Figure 5 ), and two streams of molten glass converge or fuse at the bottom edge (root) 42 of the form, where the converging forming surfaces of the form meet and form a glass ribbon 44. Edge guides 46 located at opposite ends of the form 30 minimize the lateral shrinkage of the glass ribbon 44 and produce a thicker strip, called a bead, along the edge of the glass ribbon. The bead is engaged and pulled down by counter-rotating draw rolls (not shown), enabling the formation of a glass ribbon at a high viscosity. By adjusting the rate at which the glass ribbon 44 is pulled out of the form 30, a very wide range of glass ribbon thicknesses can be produced using the fusion draw process. Once formed, the glass ribbon 44 may be cut into desired sheet sizes.

[0122] The fusion draw process that can be used to form the glass disclosed herein is described in U.S. Patent Nos. 3,338,696 and 3,682,609. The fusion draw process can produce glass substrates that do not require polishing. Current glass substrate polishing can produce glass substrates with an average surface roughness (Ra) greater than about 0.5 nanometers (nm), as measured by an atomic force microscope. Glass substrates produced by the fusion draw process can have an average surface roughness of less than about 0.5 nm as measured by an atomic force microscope. Glass substrates produced by the fusion draw process can also have an average internal stress of less than or equal to about 150 psi (1.03×10 6 Pascals) as measured by optical retardation. Of course, the appended claims should not be limited to the fusion draw process, as the embodiments described herein are equally applicable to other forming processes, such as but not limited to, the float forming process, the slot draw process, the rolling process, and other sheet forming processes known to those skilled in the art.

[0123] Relative to these alternative methods of manufacturing glass sheets, the fusion draw process (such as the process discussed above) can produce very thin, very flat, and very uniform glass sheets with a pristine surface. The slot draw process can also produce a pristine surface, but due to the change in orifice shape over time, the accumulation of volatile debris at the orifice-glass interface, and the challenges in fabricating the orifice to deliver true flat glass, the dimensional uniformity and surface quality of slot-drawn glass are generally not as good as those of fusion-drawn glass. The float process can produce very large, uniform sheets, but the surface may be significantly damaged due to contact with the float bath on one side and exposure to condensates from the float bath on the other side. This means that float glass may require polishing in high-performance display applications.

[0124] The fusion draw process may involve the rapid cooling of the glass from a high temperature, resulting in a high fictive temperature T f : The fictive temperature can be considered to represent the difference between the structural state of the glass and the state it would assume if it were fully relaxed at the temperature of interest. Reheating a glass with a glass transition temperature T g to a processing temperature T p such that T p <T g ≤T f may be affected by the glass viscosity. Since T p is less than T f , the structural state of the glass is out of equilibrium at T p , and the glass will spontaneously relax towards the structural state that is in equilibrium at T p . This relaxation rate is related to the glass at T pis inversely proportional to the effective viscosity at that time, such that a high viscosity results in a slow relaxation rate and a low viscosity results in a fast relaxation rate. The effective viscosity is inversely proportional to the fictive temperature of the glass, such that a low fictive temperature results in a high viscosity and a high fictive temperature results in a relatively low viscosity. Thus, the relaxation rate at T p is directly proportional to the fictive temperature of the glass. When the glass is reheated at T p temperature, the process introducing a high fictive temperature produces a relatively high relaxation rate.

[0125] One way to reduce the relaxation rate at T p is to increase the viscosity of the glass at that temperature. As the temperature is lowered below the annealing point, the viscosity of the melt increases. At a fixed temperature below T g , a glass with a higher annealing point has a higher viscosity than a glass with a lower annealing point. Thus, raising the annealing point can increase the viscosity of the substrate glass at T p . Generally, the compositional changes required to raise the annealing point also increase the viscosity at all other temperatures. In a non-limiting embodiment, the fictive temperature of the glass made by a melting process corresponds to a viscosity of about 10 11 to about 10 12 poise, so an increase in the annealing point of a melt-compatible glass generally also raises its fictive temperature. For a given glass, regardless of the forming process, a higher fictive temperature results in a lower viscosity at temperatures below T g . Thus, raising the fictive temperature is not conducive to an increase in viscosity, and the increase in viscosity that would otherwise be obtained by raising the annealing point. To effect a substantial change in the relaxation rate at T p , a relatively large change in the annealing point is generally required. One aspect of the exemplary glasses disclosed herein is that they can have an annealing point equal to or greater than about 700 °C. It is believed that such annealing points can produce an acceptably low rate of thermal relaxation during low temperature processing, such as a typical low temperature polysilicon rapid thermal annealing cycle.

[0126] In addition to the effect on the fictive temperature, raising the annealing point also raises the temperature of the entire melting and forming system, particularly the temperature of the formed body. For example, Eagle glass and Lotus TMThe annealing points of glasses (Corning Incorporated, Corning, NY) differ by about 50 °C, and the temperatures at which they are delivered to the former may also differ by about 50 °C. When held at temperatures above about 1310 °C for extended periods, the zircon refractory used to form the former exhibits thermal creep, which is accelerated by the weight of the former itself plus the weight of the glass on the former. A second aspect of the exemplary glasses disclosed herein is that their delivery temperatures can be less than or equal to about 1350 °C, less than or equal to about 1345 °C, less than or equal to about 1340 °C, less than or equal to about 1335 °C, less than or equal to about 1325 °C, less than or equal to about 1320 °C, less than or equal to about 1315 °C, or less than or equal to about 1310 °C. Such delivery temperatures can permit extended manufacturing campaigns without the need to replace the former or extend the time between former replacements.

[0127] In manufacturing trials of glasses with high annealing points and delivery temperatures below 1310 °C, the glasses may exhibit a greater tendency to devitrify at the root (bottom edge) of the former, particularly at the edge guides used to direct the glass over the former, relative to glasses with lower annealing points. Careful measurements of the temperature distribution on the former indicate that the edge guide temperatures are much lower than expected relative to the center temperature along the bottom edge (root) of the former, presumably due to radiative heat loss. The edge guides are maintained at temperatures below the center temperature of the former root to ensure that the glass has sufficient viscosity as it exits the root to place the glass ribbon under tension between the edge guides and thereby maintain the flat shape of the glass ribbon. Since the edge guides are located at opposite ends of the former, they are difficult to heat, and thus the temperature difference between the root center and the edge guides can be 50 °C or more.

[0128] It is believed that the increased tendency to devitrify in the fusion draw process can be understood as a function of the radiative heat loss of the glass versus temperature. The fusion is essentially an isothermal process, so the glass enters the former inlet at a specific viscosity and exits the root at a much higher viscosity, but the actual values of the viscosity are not strongly dependent on the properties of the glass or the temperature of the process. Thus, glasses with higher annealing points generally require much higher former temperatures than glasses with lower annealing points to match the delivery and exit viscosities.

[0129] It is also believed that since radiative heat loss increases with temperature and since high annealing point glasses are generally formed at higher temperatures than low annealing point glasses, the temperature difference between the center root and the edge guides generally increases with the annealing point of the glass. This may be directly related to the tendency of the glass to form devitrified products on the former or edge guides.

[0130] The liquidus temperature of a glass is defined as the highest temperature at which a crystalline phase would appear if the glass were held at that temperature indefinitely. The liquidus viscosity is the viscosity of the glass at the liquidus temperature. To avoid devitrification on the formed body, it may be helpful for the liquidus viscosity to be high enough to ensure that the glass is no longer on the refractory or edge guide material of the formed body at or near the liquidus temperature.

[0131] In practice, few E-glasses have a liquidus viscosity of the desired magnitude. Experience with display substrate glasses (e.g., Eagle glass) has shown that the edge guide can be maintained continuously at a temperature 60 °C lower than the liquidus temperature of some E-glasses. While it is understood that glasses with a higher annealing point require a higher forming temperature, it was not anticipated that the edge guide would be much colder relative to the center root temperature. A useful metric for tracking this effect is the difference T liq between the delivery temperature of the molten glass to the formed body and the liquidus temperature of the glass. In a fusion draw process, it is generally desirable to deliver the molten glass at about 35,000 poise. The temperature at which the glass exhibits a viscosity of 35,000 poise is designated as T 35kP . For a given delivery temperature, it may be useful to make T 35kP – T liq as large as possible, but for display substrates such as Eagle glass, extended manufacturing activities can be carried out if T 35kP – T liq is about 80 °C or higher. As the temperature increases, T 35kP – T liq must also increase, so for T 35kP approaching 1300 °C, it may be helpful to make T 35kP – T liq equal to or greater than about 100 °C. The minimum useful value of T 35kP – T liq varies approximately linearly with temperature from about 1200 °C to about 1320 °C and can be represented by Equation (1).

[0132] Minimum T 35kP – T liq = 0.25T 35kP – 225, (1)

[0133] where all temperatures are in °C. Thus, one or more exemplary glasses disclosed herein can have T 35kP – T liq > 0.25T 35kP – 225 °C.

[0134] In addition, the forming process may require a glass with a high liquidus viscosity to avoid devitrification products at the interface with the glass and to minimize the devitrification products visible in the final glass. Thus, for a given glass that is melt-compatible with a particular glass ribbon size and thickness, adjusting the process to make a wider or thicker glass ribbon will generally result in lower temperatures at opposite ends of the formed body. Some embodiments have a higher liquidus viscosity to provide greater flexibility for manufacturing via the melting process.

[0135] In tests of the relationship between liquidus viscosity and subsequent devitrification propensity in the melting process, high delivery temperatures, such as those of the exemplary glass, generally require a higher liquidus viscosity than in the case of typical display substrate compositions with lower annealing points for long-term production. This is believed to be due to the accelerated crystal growth rate as the temperature increases. Melting is essentially an isoviscous process, so at a certain fixed temperature, a glass with a higher viscosity can be melted at a higher temperature than a glass with a lower viscosity. While a certain degree of supercooling (cooling below the liquidus temperature) can be sustained in the glass for a longer period at a lower temperature, the crystal growth rate increases with increasing temperature, and thus a higher-viscosity glass may grow an unacceptable amount of devitrification products in a shorter time compared to a lower-viscosity glass. Depending on the location of formation, the devitrification products can compromise forming stability and introduce visible defects in the final glass.

[0136] To be formed by the fusion draw process, one or more embodiments of the glass composition can have a liquidus viscosity equal to or greater than about 100,000 poise, equal to or greater than about 120,000 poise, equal to or greater than about 140,000 poise, equal to or greater than about 175,000 poise, or equal to or greater than about 200,000 poise, including all ranges and subranges therebetween. Over the entire range of the exemplary glass, it is possible to obtain a sufficiently low liquidus temperature and a sufficiently high viscosity such that the liquidus viscosity of the glass is unusually high compared to other compositions.

[0137] In addition to the glass formers (SiO 2 , Al 2 O 3 and B 2 O 3 ), the glasses described herein can also include alkaline earth metal oxides. For example, one or more of at least three alkaline earth metal oxides can be part of the glass composition, such as MgO, CaO, and BaO, and optionally a fourth, SrO. The alkaline earth metal oxides provide various properties important for melting, clarification, forming, and end use of the glass. Thus, to improve the performance of the glass in these aspects, (MgO + CaO + SrO + BaO) / Al 2O 3 The ratio can be equal to or greater than about 1 (one). As the ratio increases, the increase in viscosity tends to be more pronounced than the increase in liquidus temperature, and thus it becomes increasingly difficult to obtain a suitably high value of T 35kP –T liq Thus, in all respects, the ratio (MgO + CaO + SrO + BaO) / Al 2 O 3 can be less than or equal to about 2. In some embodiments, the (MgO + CaO + SrO + BaO) / Al 2 O 3 ratio can be in the range from about 1 to about 1.8, from about 1 to about 1.6, from about 1 to about 1.4, from about 1 to about 1.2, from about 1 to about 1.16, or from about 1.1 to about 1.6. For example, the (MgO + CaO + SrO + BaO) / Al 2 O 3 ratio can be less than about 1.7, less than about 1.6 or less than about 1.5.

[0138] For certain embodiments, the alkaline earth metal oxides can be considered to be effectively a single constituent. This is because their effects on viscoelasticity, liquidus temperature, and liquidus phase relationships are more similar to each other in nature than their effects on the glass - forming oxides SiO 2 , Al 2 O 3 and B 2 O 3 However, the alkaline earth metal oxides CaO, SrO, and BaO can form feldspar minerals, particularly anorthite (CaAl 2 Si 2 O 8 ) and celsian (BaAl 2 Si 2 O 8 ) and their strontium - containing solid solutions, but MgO is largely not involved in these crystals. Thus, when the feldspar crystals are already in the liquidus phase, additional MgO can be used to stabilize the liquid relative to the crystals and thus lower the liquidus temperature. At the same time, the viscosity curve generally becomes steeper, reducing the melting temperature while having little or no effect on the low - temperature viscosity.

[0139] Adding a small amount of MgO can lower the melting temperature by reducing the liquidus temperature and increasing the liquidus viscosity, thus facilitating melting and shaping while maintaining a high annealing point and thus low compaction.

[0140] For those with a suitably high T 35kP –T liqFor the glass of the values, the ratio of MgO to other alkaline earth metals, MgO / (MgO + CaO + SrO + BaO), may fall within a relatively narrow range. As described above, adding MgO can destabilize feldspar minerals and thus stabilize the liquid and lower the liquidus temperature. However, once MgO reaches a certain level, mullite Al 6 Si 2 O 13 may become stable, thereby increasing the liquidus temperature and decreasing the liquidus viscosity. In addition, a higher concentration of MgO tends to lower the viscosity of the liquid, and thus even if the liquidus viscosity is kept constant by adding MgO, the liquidus viscosity will ultimately decrease. Therefore, in the examples, 0.10 ≤ MgO / (MgO + CaO + SrO + BaO) ≤ 0.40, or in other examples, 0.2 ≤ MgO / (MgO + CaO + SrO + BaO) ≤ 0.4. Within these ranges, MgO can vary relative to the glass former and other alkaline earth metal oxides to maximize the T 35kP -T liq value while obtaining other desired properties.

[0141] It is believed that calcium oxide present in the glass composition can result in a low liquidus temperature (high liquidus viscosity), a high annealing point and Young's modulus, and a CTE within the most desirable range for flat panel display applications. It is also beneficial for chemical durability, and compared with other alkaline earth metal oxides, calcium oxide is relatively inexpensive as a batch material. However, at high concentrations, CaO increases the density and CTE. In addition, at a sufficiently low SiO 2 concentration, CaO can stabilize anorthite, thereby decreasing the liquidus viscosity.

[0142] Both SrO and BaO contribute to a low liquidus temperature (high liquidus viscosity). Thus, the glass described herein may contain one or both oxides. However, the concentrations of these oxides can be selected to avoid an increase in CTE and density and a decrease in Young's modulus and annealing point. The relative proportions of SrO and BaO can be balanced to obtain a suitable combination of physical properties and liquidus viscosity such that the glass can be formed by the down-draw process.

[0143] Summarizing the effects and functions of the central components of the glass of the present disclosure, SiO 2 is a basic glass former. Al 2 O 3 and B 2 O 3 are also glass formers, and they can be selected in pairs. For example, an increase in B 2 O 3 and a corresponding decrease in Al 2 O 3 are used to obtain a lower density and CTE, while Al2 O 3 The increase of and B 2 O 3 The corresponding decrease can be used to increase the annealing point, Young's modulus and durability, as long as Al 2 O 3 The increase of does not reduce the RO / Al 2 O 3 Ratio to well below about 1, where RO = (MgO + CaO + SrO + BaO). If the ratio is too low, the fusibility is impaired, i.e., the melting temperature becomes too high. For example, due to the late melting of the silica raw material, it may be difficult to remove gaseous inclusions from the glass. B 2 O 3 Can be used to reduce the melting temperature, but a high content of B 2 O 3 May impair the annealing point.

[0144] In addition, when (MgO + CaO + SrO + BaO) / Al 2 O 3 Is less than or equal to about 1.05, mullite, an aluminosilicate crystal, can appear as a liquidus phase. Once mullite exists as a liquidus phase, the compositional sensitivity of the liquidus significantly increases, and the mullite devitrification product grows very fast and is difficult to remove once formed.

[0145] Al 2 O 3 And B 2 O 3 The concentrations of can be selected in pairs to increase the annealing point, increase Young's modulus, improve durability, reduce density and reduce the coefficient of thermal expansion (CTE), while maintaining the melting and forming characteristics of the glass. For example, an increase in B 2 O 3 And a corresponding decrease in Al 2 O 3 Can help to obtain a lower density and CTE, while an increase in Al 2 O 3 And a corresponding decrease in B 2 O 3 Can help to increase the annealing point, Young's modulus and durability, as long as the increase in Al 2 O 3 Does not reduce the (MgO + CaO + SrO + BaO) / Al 2 O 3 Ratio to well below about 1.

[0146] In addition to fusibility and annealing point considerations, for display applications, the CTE of the glass can be selected to be compatible with that of silicon. To achieve such CTE values, the RO content of the glasses disclosed herein can be controlled. For a given Al 2 O 3 content, controlling the RO content corresponds to controlling the RO / Al 2 O 3 ratio. In fact, if the RO / Al 2 O 3 ratio is below about 1.6, glasses with a suitable CTE are produced.

[0147] In addition to these considerations, one or more of the glasses disclosed herein can be formed by a down-draw process, such as a fusion process, which means that the liquidus viscosity of the glass should be relatively high. The individual alkaline earths play an important role in this regard because they can destabilize the crystalline phases that would otherwise form. BaO and SrO are particularly effective in controlling the liquidus viscosity and can be included in the exemplary glasses at least for this purpose. Various combinations of alkaline earth metals can be used to produce glasses with a high liquidus viscosity, with the total amount of alkaline earth metals meeting the RO / Al 2 O 3 ratio constraints required to achieve a low melting temperature, a high annealing point, and a suitable CTE.

[0148] In addition to the above components, the glass compositions described herein can include various other oxides to adjust the various physical, melting, fining, and forming properties of the glass. Examples of such other oxides can include, but are not limited to, TiO 2 , MnO, Fe 2 O 3 , ZnO, Nb 2 O 5 , MoO 3 , Ta 2 O 5 , WO 3 , Y 2 O 3 , La 2 O 3 and CeO 2 . In embodiments, the amount of any of these oxides can be less than or equal to 2.0 mol%, and their total combined concentration can be less than or equal to 5.0 mol%.

[0149] The glass compositions described herein can also include various contaminants associated with the batch and / or introduced into the glass by the melting, fining, and / or forming equipment used to produce the glass, particularly Fe 2 O 2 and ZrO 2 . The glass can also contain SnO 2, which is due to Joule melting using tin oxide electrodes and / or by the batch of tin-containing materials such as SnO 2 、SnO、SnCO 3 、SnC 2 O 2 and so on.

[0150] To mitigate light leakage at the edges of the display tiles, the glass disclosed herein may include intentionally added transition metal components to increase the transmission loss of the glass (reduce the optical transmittance). For example, the glass may include nickel or cobalt in an amount sufficient to obtain a reduced transmittance.

[0151] In view of the above, various glass compositions are described in the present disclosure. Among these glass compositions, SiO 2 serves as a basic glass former. In an embodiment, the concentration of SiO 2 can be greater than about 60 mol% to make the glass have a density and chemical durability suitable for a flat panel display glass substrate, and a liquidus temperature (liquidus viscosity) that allows the glass to be formed by a down-draw process (such as a fusion down-draw process). As for the upper limit, generally, the SiO 2 concentration can be equal to or less than about 80 mol% to allow the use of conventional high-capacity melting techniques, such as Joule melting in a refractory melting vessel, to melt the batch. As the SiO 2 concentration increases, the 200 poise temperature T 200P (melting temperature) generally increases. In various applications, the SiO 2 concentration can be adjusted such that the glass composition has a melting temperature of less than or equal to about 1,750 °C.

[0152] Accordingly, one or more embodiments of the present disclosure may relate to a glass comprising, in terms of oxides, SiO in the range from about 60 mol% to about 80 mol%, from about 60 mol% to about 78 mol%, from about 60 mol% to about 76 mol%, from about 60 mol% to about 72 mol%, from about 60 mol% to about 70 mol%, from about 60 mol% to about 68 mol%, from about 60 mol% to about 66 mol%, from about 60 mol% to about 64 mol%, or from about 60 mol% to about 62 mol%, including all ranges and sub-ranges therebetween. 2

[0153] In certain embodiments, the glass may include SiO in the range from about 61 mol% to about 80 mol%, such as in the range from about 62 mol% to about 80 mol%, from about 63 mol% to about 80 mol%, from about 64 mol% to about 80 mol%, from about 65 mol% to about 80 mol%, from about 66 mol% to about 80 mol%, from about 67 mol% to about 80 mol%, from about 68 mol% to about 80 mol%, from about 69 mol% to about 80 mol%, from about 70 mol% to about 80 mol%, from about 71 mol% to about 80 mol%, from about 72 mol% to about 80 mol%, from about 73 mol% to about 80 mol%, from about 74 mol% to about 80 mol%, from about 75 mol% to about 80 mol%, from about 76 mol% to about 80 mol%, from about 77 mol% to about 80 mol%, or from about 78 mol% to about 80 mol%, including all ranges and sub-ranges therebetween. 2 In other embodiments, the exemplary glass may include SiO in the range from about 61 mol% to about 73 mol%, such as in the range from about 61 mol% to about 72 mol%, from about 61 mol% to about 71 mol%, from about 61 mol% to about 70 mol%, from about 61 mol% to about 69 mol%, from about 61 mol% to about 68 mol%, from about 61 mol% to about 67 mol%, from about 61 mol% to about 66 mol%, from about 61 mol% to about 65 mol%, from about 61 mol% to about 64 mol%, from about 61 mol% to about 63 mol%, or from about 61 mol% to about 62 mol%, including all ranges and sub-ranges therebetween.

[0154] 2 2 In other embodiments, the exemplary glass may include SiO in the range from about 61 mol% to about 73 mol%, such as in the range from about 61 mol% to about 72 mol%, from about 61 mol% to about 71 mol%, from about 61 mol% to about 70 mol%, from about 61 mol% to about 69 mol%, from about 61 mol% to about 68 mol%, from about 61 mol% to about 67 mol%, from about 61 mol% to about 66 mol%, from about 61 mol% to about 65 mol%, from about 61 mol% to about 64 mol%, from about 61 mol% to about 63 mol%, or from about 61 mol% to about 62 mol%, including all ranges and sub-ranges therebetween.

[0155] Al 2 O 3 is another glass former used to make the glass described herein. An Al 2 O 3 concentration equal to or greater than about 9 mol% provides the glass with a low liquidus temperature and high viscosity, resulting in a high liquidus viscosity. Using at least 9 mol% of Al 2 O 3 also increases the annealing point and Young's modulus of the glass. To obtain a ratio (MgO + CaO + SrO + BaO) / Al 2 O 3 equal to or greater than about 1, the Al 2 O 3 concentration may be less than about 15 mol%. For example, the glass may include an Al2 O 3 Amounts, for example in the range from about 9 mol% to about 14 mol%, from about 10 mol% to about 14 mol%, from about 11 mol% to about 14 mol%, from about 12 mol% to about 14 mol%, or from about 13 mol% to about 14 mol%, including all ranges and sub - ranges therebetween. In other embodiments, the glass may include Al in the range from about 9 mol% to about 13 mol%, from about 9 mol% to about 12 mol%, from about 9 mol% to about 11 mol%, or from about 9 mol% to about 10 mol% 2 O 3 amounts, including all ranges and sub - ranges therebetween.

[0156] B 2 O 3 is both a glass - former and a flux that aids in melting and reduces the melting temperature. B 2 O 3 has an effect on both the liquidus temperature and the viscosity. Increasing B 2 O 3 can be used to increase the liquidus viscosity of the glass. To achieve these effects, the glass compositions disclosed herein may have a B 2 O 3 concentration equal to or greater than 0 mol%. As discussed above, the durability of the glass is important for LCD applications. Durability can be somewhat controlled by increasing the concentration of alkaline earth metal oxides and is significantly reduced by increasing the B 2 O 3 content. The annealing point decreases with increasing B 2 O 3 , so it may be helpful to keep the B 2 O 3 content relatively low compared to its typical concentration in amorphous silicon display substrates. Thus, the glass may include B 2 O 3The amount, for example, in the range from about 0 mol% to about 12 mol%, such as the range from about 0.1 mol% to about 12 mol%, the range from about 0.5 mol% to about 12 mol%, the range from about 1 mol% to about 12 mol%, the range from about 2 mol% to about 12 mol%, the range from about 3 mol% to about 12 mol%, the range from about 4 mol% to about 12 mol%, the range from about 5 mol% to about 12 mol%, the range from about 6 mol% to about 12 mol%, the range from about 7 mol% to about 12 mol%, the range from about 8 mol% to about 12 mol%, the range from about 9 mol% to about 12 mol%, the range from about 10 mol% to about 12 mol%, or the range from about 11 mol% to about 12 mol%, including all ranges and sub-ranges therebetween.

[0157] In other embodiments, the glass may include B in the range from about 0 mol% to about 11 mol%, the range from about 0.1 mol% to about 10 mol%, the range from about 0.1 mol% to about 9 mol%, the range from about 0.1 mol% to about 8 mol%, the range from about 0.1 mol% to about 7 mol%, the range from about 0.1 mol% to about 6 mol%, the range from about 0.1 mol% to about 5 mol%, the range from about 0.1 mol% to about 4 mol%, the range from about 0.1 mol% to about 3 mol%, the range from about 0.1 mol% to about 2 mol%, the range from about 0.1 mol% to about 1 mol%, or the range from about 0.1 mol% to about 0.5 mol%, including all ranges and sub-ranges therebetween. 2 O 3 amount, including all ranges and sub-ranges therebetween.

[0158] The glass may further include an amount of MgO equal to or less than about 9 mol%, for example, in the range from about 0 mol% to about 9 mol%, such as the range from about 0.5 mol% to about 9 mol%, the range from about 1 mol% to about 9 mol%, such as the range from about 2 mol% to about 9 mol%, the range from about 3 mol% to about 9 mol%, the range from about 4 mol% to about 9 mol%, the range from about 5 mol% to about 9 mol%, the range from about 6 mol% to about 9 mol%, or the range from about 7 mol% to about 9 mol%, including all ranges and sub-ranges therebetween.

[0159] In other embodiments, the glass may include an amount of MgO in the range from about 0 mol% to about 8 mol%, the range from about 0.5 mol% to about 7 mol%, the range from about 0.5 mol% to about 6 mol%, the range from about 0.5 mol% to about 5 mol%, the range from about 0.5 mol% to about 4 mol%, the range from about 0.5 mol% to about 3 mol%, the range from about 0.5 mol% to about 2 mol%, or the range from about 0.5 mol% to about 1 mol%, including all ranges and sub-ranges therebetween.

[0160] The glass may further include CaO in the range from about 3 mol% to about 12 mol%, such as in the range from about 3 mol% to about 11 mol%, from about 3 mol% to about 10 mol%, from about 3 mol% to about 9 mol%, from about 3 mol% to about 8 mol%, from about 3 mol% to about 7 mol%, from about 3 mol% to about 6 mol%, from about 3 mol% to about 5 mol%, or from about 3 mol% to about 4 mol%.

[0161] In other embodiments, the glass may include an amount of CaO in the range from about 4 mol% to about 12 mol%, from about 5 mol% to about 12 mol%, from about 6 mol% to about 12 mol%, from about 7 mol% to about 12 mol%, from about 8 mol% to about 12 mol%, from about 9 mol% to about 12 mol%, from about 10 mol% to about 12 mol%, or from about 11 mol% to about 12 mol%, including all ranges and sub-ranges therebetween.

[0162] The glass may further include an amount of SrO equal to or less than about 5 mol%, such as in the range from about 0 mol% to about 5 mol%, such as from about 0 mol% to about 4 mol%, from about 0 mol% to about 3 mol%, from about 0 mol% to about 2 mol%, or from about 0 mol% to about 1 mol%.

[0163] In other embodiments, the glass may include an amount of SrO in the range from about 0.05 mol% to about 5 mol%, from about 0.1 mol% to about 5 mol%, from about 0.2 mol% to about 5 mol%, from about 0.5 mol% to about 5 mol%, from about 1 mol% to about 5 mol%, from about 2 mol% to about 5 mol%, from about 3 mol% to about 5 mol%, or from about 4 mol% to about 5 mol%, including all ranges and sub-ranges therebetween.

[0164] The glass may further include an amount of BaO equal to or less than about 5 mol%, such as in the range from about 0 mol% to about 5 mol%, such as from about 0 mol% to about 4 mol%, from about 0 mol% to about 3 mol%, from about 0 mol% to about 2 mol%, or from about 0 mol% to about 1 mol%, including all ranges and sub-ranges therebetween.

[0165] In other embodiments, the glass may include an amount of BaO in the range from about 0.1 mol% to about 5 mol%, from about 0.2 mol% to about 5 mol%, from about 0.5 mol% to about 5 mol%, from about 1 mol% to about 5 mol%, from about 2 mol% to about 5 mol%, from about 3 mol% to about 5 mol%, or from about 4 mol% to about 5 mol%, including all ranges and subranges therebetween.

[0166] The glass may include RO (i.e., MgO, CaO, SrO, and / or BaO) such that (MgO + CaO + SrO + BaO) / Al 2 O 3 is equal to or less than about 1.6, such as in the range from about 1 to about 1.5, from about 1 to about 1.4, from about 1 to about 1.3, from about 1 to about 1.2, or from about 1 to about 1.1, including all ranges and subranges therebetween. In other embodiments, the glass may include an amount of RO such that (MgO + CaO + SrO + BaO) / Al 2 O 3 is in the range from about 1.1 to about 1.6, from about 1.2 to about 1.6, from about 1.3 to about 1.6, from about 1.4 to about 1.6, or from about 1.5 to about 1.6, including all ranges and subranges therebetween.

[0167] As previously discussed, a (MgO + CaO + SrO + BaO) / Al 2 O 3 ratio equal to or greater than about 1 may improve clarification, i.e., removal of gaseous inclusions from the melt batch. This allows for more environmentally friendly clarification. Thus, the glasses disclosed herein may include chemical clarifying agents. Suitable clarifying agents may include but are not limited to SnO 2 、As 2 O 3 、Sb 2 O 3 、F, Cl, and Br. In an embodiment, the chemical clarifying agent may include one or more of SnO 2 、As 2 O 3 、Sb 2 O 3 、F, Cl, and / or Br at a concentration less than or equal to about 0.5 mol%, such as equal to or less than about 0.45 mol%, equal to or less than about 0.4 mol%, equal to or less than about 0.35 mol%, equal to or less than about 0.3 mol%, or equal to or less than about 0.25 mol%. In an embodiment, the glass may include SnO in the range from about 0.01 mol% to about 0.4 mol% 2 、As2 O3, Sb 2 O 3 , F, Cl, and / or any one or combination of Br. In certain embodiments, the glass composition may include Fe in the range of about 0.005 mol% to about 0.2 mol% 2 O 3 , CeO 2 and / or MnO 2 in any one or combination thereof.

[0168] As 2 O 3 is an effective high-temperature fining agent for display glass, and in some embodiments described herein, As 2 O 3 can be used for fining because it has excellent fining properties. However, As 2 O 3 is toxic and requires special disposal during the glass manufacturing process. Therefore, in embodiments, fining can be performed without using a large amount of As 2 O 3 , i.e., the finished glass can have at most 0.05 mol% of As 2 O 3 . In various embodiments, As 2 O 3 is not used when fining the glass. In such cases, due to contaminants present in the batch and / or the equipment used to melt the batch, the finished glass will typically have at most 0.005 mol% of As 2 O 3 .

[0169] Although less toxic than As 2 O 3 , Sb 2 O 3 is also toxic and requires special disposal. Additionally, compared to glass using As 2 O 3 or SnO 2 as a fining agent, Sb 2 O 3 increases the density of the glass, increases the CTE, and decreases the annealing point. Therefore, in certain embodiments, fining can be performed without using a large amount of Sb 2 O 3 , i.e., the finished glass has at most 0.05 mol% of Sb 2 O 3 . In other embodiments, Sb 2 O 3。In such cases, due to contaminants present in the batch and / or the equipment used to melt the batch, the finished glass will typically have at most 0.005 mole % of Sb 2 O 3 。

[0170] Compared with As 2 O 3 and Sb 2 O 3 clarification, tin clarification (i.e., SnO 2 clarification) is less effective, but SnO 2 is a ubiquitous material and has no known hazardous properties. In addition, for many years, SnO 2 has been a component of display glass manufactured using tin oxide electrodes during the Joule melting of the batch. The presence of SnO 2 in display glass has not led to any known adverse effects in the manufacture of flat panel displays. However, high concentrations of SnO 2 are not preferred because this can lead to the formation of crystal defects in the display glass. Therefore, the concentration of SnO 2 in the finished glass can be maintained at less than or equal to 0.25 mole %.

[0171] The higher viscosity glasses described herein can permit higher concentrations of SnO 2 without causing any harmful effects. For example, the conventional view is that glasses with a high annealing point result in a high melting temperature. Such a high melting temperature can lead to an increase in inclusions in the corresponding glass. To address the presence of such inclusions, clarifying agents can be added. However, glasses with a low viscosity generally do not permit the addition of SnO 2 because it crystallizes in the glass. However, as described herein, exemplary glasses can have a higher viscosity, resulting in a higher forming temperature. Therefore, higher concentrations of clarifying agents can be added to the glass and fewer inclusions are produced. In short, by changing the composition of the exemplary glass to produce a higher processing temperature, a larger amount of clarifying agent can be added to remove inclusions before crystallization occurs. Therefore, the exemplary glass can include SnO 2 at a concentration between about 0.001 mole % and about 0.5 mole %, and have a T 35kP equal to or greater than about 1170 °C, equal to or greater than about 1200 °C, equal to or greater than about 1290 °C, or equal to or greater than about 1300 °C. The exemplary glass can include SnO 2 at a concentration in the range from about 0.001 mole % to about 0.5 mole %, and have a T 200POther exemplary glasses can include SnO at a concentration in the range from about 0.001 mol% to about 0.5 mol%. 2 and having a liquidus temperature equal to or greater than about 1080 °C, equal to or greater than about 1150 °C, or equal to or greater than about 1290 °C. Such glasses can also have T as discussed above 35kP and / or T 200P . As previously described, SnO can be incorporated into the glass by Joule melting using a tin oxide electrode and / or by the batch of a tin-containing material, such as SnO 2 , SnO, SnCO 3 , SnC 2 O 2 , etc. 2 .

[0172] If desired, tin fining can be used alone or in combination with other fining techniques. For example, tin fining can be combined with halide fining, such as bromine fining. Other possible combinations include, but are not limited to, tin fining plus sulfate, sulfide, cerium oxide, mechanical bubbling, and / or vacuum fining. It is contemplated that these other fining techniques can be used alone. In an embodiment, (MgO + CaO + SrO + BaO) / Al 2 O 3 and the individual alkaline earth metal concentrations are maintained within the ranges discussed herein to make the fining process easier to perform and more efficient.

[0173] The glass compositions disclosed herein can include specifically added transition metal oxides to reduce the average optical transmittance of the glass. For example, the glasses described herein can include nickel (e.g., NiO) and / or cobalt (e.g., Co 3 O 4 ), in an amount sufficient to produce an average optical transmittance in the range from about 50% to about 90% in the wavelength range from about 450 nm to about 650 nm in the glass article (when measured with a power meter through a thickness of 0.7 mm), such as in the range from about 60% to 85%, from about 60% to about 83%, from about 60% to about 81%, from about 60% to about 79%, from about 60% to about 77%, from about 60% to about 75%, from about 60% to about 73%, from about 60% to about 71%, from about 60% to about 69%, from about 60% to about 67%, or from about 60% to about 65%.

[0174] In other embodiments, the glass can have an average transmission ratio in the range from about 62% to about 90%, from about 64% to about 90%, from about 66% to about 90%, from about 68% to about 90%, from about 70% to about 90%, from about 72% to about 90%, from about 74% to about 90%, from about 76% to about 90%, from about 78% to about 90%, from about 80% to about 90%, or from about 82% to about 90%, including all ranges and sub-ranges therebetween. As used herein, the average transmission ratio refers to the average of all transmission ratios of a given glass article (such as a glass substrate) within the wavelength range. See, for example Figure 6 , which depicts the transmission ratios of several different compositions. In fact, the data show that for any given sample, the transmission ratio between 450 nanometers and 650 nanometers falls within + / - 5% of the average transmission ratio, indicating a very flat transmission ratio response to wavelengths within the wavelength range.

[0175] The glass can include NiO in the range from about 0 mol% to about 0.15 mol%, from about 0.025 mol% to about 0.15 mol%, from about 0.035 mol% to about 0.15 mol%, from about 0.045 mol% to about 0.15 mol%, from about 0.055 mol% to about 0.15 mol%, from about 0.065 mol% to about 0.15 mol%, from about 0.075 mol% to about 0.15 mol%, from about 0.085 mol% to about 0.15 mol%, from about 0.095 mol% to about 0.15 mol%, from about 0.105 mol% to about 0.15 mol%, from about 0.110 mol% to about 0.15 mol%, from about 0.115 mol% to about 0.15 mol%, from about 0.120 mol% to about 0.15 mol%, or from about 0.125 mol% to about 1.5 mol%, including all ranges and sub-ranges therebetween.

[0176] In other embodiments, the glass can include NiO in the range from about 0 mol% to about 0.14 mol%, from about 0 mol% to about 0.13 mol%, from about 0 mol% to about 0.12 mol%, from about 0 mol% to about 0.11 mol%, from about 0 mol% to about 0.10 mol%, from about 0 mol% to about 0.09 mol%, from about 0 mol% to about 0.08 mol%, from about 0 mol% to about 0.07 mol%, from about 0 mol% to about 0.06 mol%, or from about 0 mol% to about 0.05 mol%, including all ranges and sub-ranges therebetween.

[0177] Alternatively or additionally, the glass may include Co in the range from about 0 mol% to about 0.05 mol%, such as in the range from about 0 mol% to about 0.045 mol%, from about 0 mol% to about 0.04 mol%, from about 0 mol% to about 0.035 mol%, from about 0 mol% to about 0.03 mol%, from about 0 mol% to about 0.025 mol%, from about 0 mol% to about 0.02 mol%, from about 0 mol% to about 0.015 mol%, or from about 0 mol% to about 0.01 mol%, including all ranges and sub-ranges therebetween. 3 O 4 , including all ranges and sub-ranges therebetween.

[0178] In other embodiments, the glass may include Co in the range from about 0.01 mol% to about 0.05 mol%, from about 0.015 mol% to about 0.05 mol%, from about 0.02 mol% to about 0.05 mol%, from about 0.025 mol% to about 0.05 mol%, from about 0.03 mol% to about 0.05 mol%, from about 0.035 mol% to about 0.05 mol%, from about 0.04 mol% to about 0.05 mol%, or from about 0.045 mol% to about 0.05 mol%, including all ranges and sub-ranges therebetween. In certain embodiments, the glass may include Co in the range from about 0.005 mol% to about 0.05 mol%, such as in the range from about 0.01 mol% to about 0.04 mol%. 3 O 4 , including all ranges and sub-ranges therebetween. 3 O 4 , including all ranges and sub-ranges therebetween.

[0179] The glass may contain an amount of Fe equal to or less than about 0.02 mol%, such as equal to or less than about 0.01 mol%. 2 O 3 amount.

[0180] When tested using a Cary 60 spectrometer from Agilent Technologies with FL2 illumination, a 10-degree observation angle, and a sample thickness of 0.7 mm, the glass with reduced optical transmittance disclosed herein may have color coordinates including a luminance value L* of less than about 94 (e.g., in the range from about 83 to about 94), a red-green coordinate a* in the range from about -0.87 to about 0.02, and a yellow-blue coordinate b* in the range from about -2.30 to about 1.85.

[0181] The annealing point (i.e., the annealing temperature) is the temperature at which the glass viscosity drops to 10 13 poise (10 13 dyne-second / cm2 )The following temperature. At such a viscosity, the glass is still too hard to undergo significant external deformation without breaking, but soft enough to relieve internal strain. The glass disclosed herein can have an annealing point equal to or greater than about 700 °C, such as in the range from about 700 °C to about 810 °C, from about 710 °C to about 810 °C, from about 720 °C to about 810 °C, from about 730 °C to about 810 °C, from about 740 °C to about 810 °C, from about 750 °C to about 810 °C, from about 760 °C to about 810 °C, from about 770 °C to about 810 °C, from about 780 °C to about 810 °C, from about 790 °C to about 810 °C, or from about 800 °C to about 810 °C, including all ranges and sub-ranges therebetween.

[0182] In other embodiments, the glass can have an annealing point in the range from about 700 °C to about 800 °C, from about 700 °C to about 790 °C, from about 700 °C to about 780 °C, from about 700 °C to about 770 °C, from about 700 °C to about 760 °C, from about 700 °C to about 750 °C, from about 700 °C to about 740 °C, from about 700 °C to about 730 °C, from about 700 °C to about 720 °C, or from about 700 °C to about 710 °C, including all ranges and sub-ranges therebetween.

[0183] The strain point is the temperature at which the glass viscosity exceeds 10 14.5 poises upon cooling. The glass disclosed herein can include a strain point in the range from about 660 °C to about 760 °C, such as from about 660 °C to about 750 °C, from about 660 °C to about 740 °C, from about 660 °C to about 730 °C, from about 660 °C to about 720 °C, from about 660 °C to about 710 °C, from about 660 °C to about 700 °C, from about 660 °C to about 680 °C, or from about 660 °C to about 670 °C, including all ranges and sub-ranges therebetween.

[0184] In other embodiments, the glass may include a strain point in the range from about 670 °C to about 760 °C, such as in the range from about 680 °C to about 760 °C, from about 690 °C to about 760 °C, from about 700 °C to about 760 °C, from about 710 °C to about 760 °C, from about 720 °C to about 760 °C, from about 730 °C to about 760 °C, from about 740 °C to about 760 °C, or from about 750 °C to about 760 °C, including all ranges and sub - ranges therebetween. In a particular embodiment, the glass may include a strain point in the range from about 667 °C to about 752 °C, including all ranges and sub - ranges therebetween.

[0185] Young's modulus is a measure of tensile or compressive stress (i.e., force per unit area) and the resulting strain produced by that force in the linear elastic region of the glass. The glass disclosed herein may exhibit a Young's modulus greater than about 69 GPa, such as in the range from about 69 GPa to about 85 GPa, from about 70 GPa to about 85 GPa, from about 71 GPa to about 85 GPa, from about 72 GPa to about 85 GPa, from about 73 GPa to about 85 GPa, from about 74 GPa to about 85 GPa, from about 75 GPa to about 85 GPa, from about 76 GPa to about 85 GPa, from about 77 GPa to about 85 GPa, from about 78 GPa to about 85 GPa, from about 79 GPa to about 85 GPa, from about 80 GPa to about 85 GPa, from about 81 GPa to about 85 GPa, from about 82 GPa to about 85 GPa, from about 83 GPa to about 85 GPa, or from about 84 GPa to about 85 GPa, including all ranges and sub - ranges therebetween.

[0186] In other embodiments, the glass may include a Young's modulus in the range from about 69 gigapascals (GPa) to about 84 GPa, such as in the range from about 69 GPa to about 83 GPa, from about 69 GPa to about 82 GPa, from about 69 GPa to about 81 GPa, from about 69 GPa to about 80 GPa, from about 69 GPa to about 79, from about 69 GPa to about 78 GPa, from about 69 GPa to about 77 GPa, from about 69 GPa to about 76 GPa, from about 69 GPa to about 75 GPa, from about 69 GPa to about 74 GPa, from about 69 GPa to about 73 GPa, from about 69 GPa to about 72 GPa, from about 69 GPa to about 71 GPa, or from about 69 GPa to about 70 GPa, including all ranges and sub - ranges therebetween.

[0187] In an embodiment, the glass transition temperature (T 35kP ) may be equal to or less than about 1340 °C, equal to or less than about 1330 °C, equal to or less than about 1320 °C, equal to or less than about 1310 °C, equal to or less than about 1300 °C, equal to or less than about 1280 °C, equal to or less than about 1260 °C, equal to or less than about 1240 °C, equal to or less than about 1220 °C, equal to or less than about 1200 °C, or equal to or less than about 1180 °C. For example, the glass may have a T in the range from about 1160 °C to about 1340 °C, from about 1170 °C to about 1340 °C, from about 1200 °C to about 1340 °C, from about 1220 °C to about 1340 °C, from about 1240 °C to about 1340 °C, from about 1260 °C to about 1340 °C, from about 1280 °C to about 1340 °C, from about 1300 °C to about 1340 °C, or from about 1320 °C to about 1340 °C, including all ranges and sub-ranges therebetween. 35kP , including all ranges and sub-ranges therebetween.

[0188] In an embodiment, the glass transition temperature (T 200P ) may be equal to or less than about 1700 °C, for example in the range from about 1530 °C to about 1700 °C, from about 1540 °C to about 1700 °C, from about 1550 °C to about 1700 °C, from about 1560 °C to about 1700 °C, from about 1570 °C to about 1700 °C, from about 1580 °C to about 1700 °C, from about 1590 °C to about 1700 °C, from about 1600 °C to about 1700 °C, from about 1610 °C to about 1700 °C, from about 1620 °C to about 1700 °C, from about 1630 °C to about 1700 °C, from about 1640 °C to about 1700 °C, from about 1650 °C to about 1700 °C, from about 1660 °C to about 1700 °C, from about 1670 °C to about 1700 °C, from about 1680 °C to about 1700 °C, or from about 1690 °C to about 1700 °C, including all ranges and sub-ranges therebetween.

[0189] In other embodiments, T 200PIt may be in the range from about 1530 °C to about 1690 °C, from about 1530 °C to about 1680 °C, from about 1530 °C to about 1660 °C, from about 1530 °C to about 1650 °C, from about 1530 °C to about 1640 °C, from about 1530 °C to about 1630 °C, from about 1530 °C to about 1620 °C, from about 1530 °C to about 1610 °C, from about 1530 °C to about 1600 °C, from about 1530 °C to about 1590 °C, from about 1530 °C to about 1580 °C, from about 1530 °C to about 1570 °C, from about 1530 °C to about 1560 °C, from about 1530 °C to about 1150 °C, or from about 1530 °C to about 1540 °C, including all ranges and sub-ranges therebetween.

[0190] The liquidus temperature (T liq ) of the glass is such a temperature above which no crystalline phase can coexist in equilibrium with the glass. In an embodiment, the glass disclosed herein may have a T in the range from about 1090 °C to about 1290 °C, such as from about 1090 °C to about 1260 °C, from about 1090 °C to about 1230 °C, from about 1090 °C to about 1200 °C, from about 1090 °C to about 1180 °C, from about 1090 °C to about 1160 °C, from about 1090 °C to about 1140 °C, or from about 1090 °C to about 1120 °C. liq This ensures a minimum tendency of devitrification on the formed body during the forming process.

[0191] In other embodiments, T liq may be in the range from about 1100 °C to about 1290 °C, from about 1120 °C to about 1290 °C, from about 1140 °C to about 1290 °C, from about 1160 °C to about 1290 °C, from about 1180 °C to about 1290 °C, from about 1200 °C to about 1290 °C, from about 1220 °C to about 1290 °C, from about 1240 °C to about 1290 °C, or from about 1260 °C to about 1290 °C, including all ranges and sub-ranges therebetween.

[0192] The glass disclosed herein can exhibit a liquidus viscosity of from about 69 kilopascals (kPa) to about 630 kPa at the liquidus temperature, such as in the range from about 100 kPa to about 500 kPa, from about 100 kPa to about 400 kPa, from about 100 kPa to about 300 kPa, or from about 100 kPa to about 200 kPa, including all ranges and sub-ranges therebetween. In other embodiments, the glass disclosed herein can include a liquidus viscosity in the range from about 200 kPa to about 400 kPa or from about 300 kPa to about 400 kPa, including all ranges and sub-ranges therebetween.

[0193] In an embodiment, an exemplary glass can exhibit T 35kP –T liq >0.25T 35kP – 225 °C.

[0194] In various aspects, the density of the glass disclosed herein can be less than about 2.7 g / cc, less than about 2.65 g / cc, less than about 2.61 g / cc, less than about 2.6 g / cc, or less than about 2.55 g / cc. In various embodiments, the density can be in the range from about 2.34 g / cc to about 2.65 g / cc or from about 2.40 g / cc to about 2.62 g / cc, including all ranges and sub-ranges therebetween.

[0195] In one or more embodiments, the thermal expansion coefficient (in the temperature range from 0 °C to 300 °C) of the glass disclosed herein can be in the range from about 28×10 -7 / °C to about 40×10 -7 / °C, from about 28×10 -7 / °C to about 38×10 -7 / °C, from about 28×10 -7 / °C to about 36×10 -7 / °C, from about 28×10 -7 / °C to about 34×10 -7 / °C, from about 28×10 -7 / °C to about 32×10 -7 / °C, or from about 28×10 -7 / °C to about 30×10 -7 / °C, including all ranges and sub-ranges therebetween. In other embodiments, the glass can include a thermal expansion coefficient in the range from about 30×10 -7 / °C to about 40×10 -7 / °C, from about 32×10 -7 / °C to about 40×10 -7 / °C, from about 34×10 -7 / °C to about 40×10 -7 / °C, in the range from about 36×10 -7 / °C to about 40×10 -7 / °C, in the range from about 38×10 -7 / °C to about 40×10 -7 / °C, including all ranges and sub - ranges therebetween.

[0196] One or more specific embodiments may relate to a glass comprising SiO in the range from about 68 mol% to about 72 mol%, such as in the range from about 69 mol% to about 72 mol%, from about 70 mol% to about 72 mol%, or from about 71 mol% to about 72 mol%, based on oxide - based mole percentages, 2 including all ranges and sub - ranges therebetween.

[0197] In other embodiments, the glass may comprise SiO in the range from about 68 mol% to about 71 mol%, from about 68 mol% to about 70 mol%, or from about 68 mol% to about 69 mol%, 2 including all ranges and sub - ranges therebetween.

[0198] The glass may comprise Al in the range from about 10 mol% to about 14 mol%, such as in the range from about 10.5 mol% to about 14 mol%, from about 11 mol% to about 14 mol%, from about 11.5 mol% to about 14 mol%, from about 12 mol% to about 14 mol%, from about 12.5 mol% to about 14 mol%, from about 13 mol% to about 14 mol%, or from about 13.5 mol% to about 14 mol%, 2 O 3 including all ranges and sub - ranges therebetween.

[0199] The glass may comprise B in the range from equal to or greater than 0 mol% to about 2 mol%, such as in the range from about 0.1 mol% to about 2 mol%, from about 0.2 mol% to about 2 mol%, from about 0.4 mol% to about 2 mol%, from about 0.1 mol% to about 7 mol%, from about 0.1 mol% to about 6 mol%, from about 0.1 mol% to about 5 mol%, from about 0.1 mol% to about 4 mol%, from about 0.6 mol% to about 2 mol%, from about 0.8 mol% to about 2 mol%, from about 1 mol% to about 2 mol%, from about 1.2 mol% to about 2 mol%, from about 1.4 mol% to about 2 mol%, from about 1.6 mol% to about 2 mol%, or from about 1.8 mol% to about 2 mol%, 2O 3 , including all ranges and sub - ranges therebetween.

[0200] The glass may include MgO in the range from about 3 mol% to about 9 mol%, such as in the range from about 3.5 mol% to about 9 mol%, from about 4 mol% to about 9 mol%, from about 4.5 mol% to about 9 mol%, from about 5 mol% to about 9 mol%, from about 5.5 mol% to about 9 mol%, from about 6 mol% to about 9 mol%, from about 6.5 mol% to about 9 mol%, from about 7 mol% to about 9 mol%, from about 7.5 mol% to about 9 mol%, from about 8 mol% to about 9 mol%, or from about 8.5 mol% to about 9 mol%, including all ranges and sub - ranges therebetween.

[0201] The glass may include CaO in the range from about 3.5 mol% to about 6 mol%, such as in the range from about 3.75 mol% to about 6 mol%, from about 4 mol% to about 6 mol%, from about 4.5 mol% to about 6 mol%, from about 5 mol% to about 6 mol%, or from about 5.5 mol% to about 6 mol%, including all ranges and sub - ranges therebetween.

[0202] The glass may include SrO in the range from about 1 mol% to about 2 mol%, such as in the range from about 1.2 mol% to about 2 mol%, from about 1.4 mol% to about 2 mol%, from about 1.6 mol% to about 2 mol%, from about 1.8 mol% to about 2 mol%, including all ranges and sub - ranges therebetween.

[0203] The glass may include BaO in the range from about 3 mol% to about 5 mol%, such as in the range from about 3.5 mol% to about 5 mol%, from about 4 mol% to about 5 mol%, from about 4.5 mol% to about 5 mol%, including all ranges and sub - ranges therebetween.

[0204] The glass may include RO (i.e., MgO, CaO, SrO, and / or BaO) such that (MgO + CaO + SrO + BaO) / Al 2 O 3 is equal to or greater than about 1, such as in the range from about 1 to about 1.6, from about 1 to about 1.5, from about 1 to about 1.4, from about 1 to about 1.3, or from about 1 to about 1.2, including all ranges and sub - ranges therebetween.

[0205] In other embodiments, the glass may include an amount of RO such that (MgO + CaO + SrO + BaO) / Al 2 O 3In the range from about 1.1 to about 1.6, such as in the range from about 1.2 to about 1.6, from about 1.3 to about 1.6, from about 1.4 to about 1.6, or from about 1.5 to about 1.6, including all ranges and sub-ranges therebetween.

[0206] The glass may include NiO in the range from about 0.05 mol% to about 0.15 mol%, such as in the range from about 0.075 mol% to about 0.15 mol%, from about 0.1 mol% to about 0.15 mol%, or from about 0.125 mol% to about 0.15 mol%, including all ranges and sub-ranges therebetween.

[0207] The glass may include Co in the range from about 0.01 mol% to about 0.05 mol%, such as in the range from about 0.02 mol% to about 0.05 mol%, from about 0.03 mol% to about 0.05 mol%, or from about 0.04 mol% to about 0.05 mol% 3 O 4 , including all ranges and sub-ranges therebetween.

[0208] The glass may include Fe in an amount equal to or less than about 0.02 mol%, such as equal to or less than about 0.01 mol% 2 O 3 amount.

[0209] The glass may be substantially free of alkali metal oxides.

[0210] The glass may have an annealing point equal to or greater than about 800 °C, such as in the range from about 800 °C to about 810 °C, from about 802 °C to about 810 °C, from about 804 °C to about 810 °C, from about 806 °C to about 810 °C, or from about 808 °C to about 810 °C, including all ranges and sub-ranges therebetween.

[0211] In other embodiments, the glass may have an annealing point in the range from about 800 °C to about 808 °C, from about 800 °C to about 806 °C, from about 800 °C to about 804 °C, or from about 800 °C to about 802 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may have an annealing point in the range from about 801 °C to about 805 °C, including all ranges and sub-ranges therebetween.

[0212] The glass may include a strain point in the range from about 740 °C to about 760 °C, such as in the range from about 740 °C to about 758 °C, from about 740 °C to about 756 °C, from about 740 °C to about 754 °C, from about 740 °C to about 752 °C, from about 740 °C to about 750 °C, from about 740 °C to about 748 °C, from about 740 °C to about 746 °C, from about 740 °C to about 744 °C, or from about 740 °C to about 742 °C, including all ranges and sub - ranges therebetween.

[0213] In other embodiments, the glass may include a strain point in the range from about 742 °C to about 760 °C, such as in the range from about 744 °C to about 760 °C, from about 746 °C to about 760 °C, from about 748 °C to about 760 °C, from about 750 °C to about 760 °C, from about 752 °C to about 760 °C, from about 754 °C to about 760 °C, from about 756 °C to about 760 °C, or from about 758 °C to about 760 °C, including all ranges and sub - ranges therebetween. In a particular embodiment, the glass may include a strain point in the range from about 748 °C to about 752 °C, including all ranges and sub - ranges therebetween.

[0214] The glass may include a Young's modulus equal to or greater than about 81 GPa, such as in the range from about 81 GPa to about 85 GPa, from about 82 GPa to about 85 GPa, or from about 84 GPa to about 85 GPa, including all ranges and sub - ranges therebetween.

[0215] In other embodiments, the glass may include a Young's modulus in the range from about 82 GPa to about 85 GPa, from about 83 GPa to about 85 GPa, or from about 84 GPa to about 85 GPa, including all ranges and sub - ranges therebetween. In a particular embodiment, the glass may include a Young's modulus in the range from about 81.9 GPa to about 84.4 GPa, including all ranges and sub - ranges therebetween.

[0216] The glass may have a T equal to or less than about 1700 °C 200P, for example, in the range from about 1680 °C to about 1700 °C, from about 1682 °C to about 1700 °C, from about 1684 °C to about 1700 °C, from about 1686 °C to about 1700 °C, from about 1688 °C to about 1700 °C, from about 1690 °C to about 1700 °C, from about 1692 °C to about 1700 °C, from about 1694 °C to about 1700 °C, from about 1696 °C to about 1700 °C, from about 1698 °C to about 1700 °C, including all ranges and sub-ranges therebetween.

[0217] In other embodiments, T 200P can be in the range from about 1680 °C to about 1698 °C, from about 1680 °C to about 1696 °C, from about 1680 °C to about 1694 °C, from about 1680 °C to about 1692 °C, from about 1680 °C to about 1690 °C, from about 1680 °C to about 1688 °C, from about 1680 °C to about 1686 °C, from about 1680 °C to about 1684 °C, or from about 1680 °C to about 1682 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, T 200P can be in the range from about 1681 °C to about 1696 °C, including all ranges and sub-ranges therebetween.

[0218] In an embodiment, the glass transition temperature (T 35kP ) at a viscosity of about 35,000 poise can be in the range from about 1290 °C to about 1310 °C, from about 1300 °C to about 1310 °C, from about 1302 °C to about 1310 °C, from about 1304 °C to about 1310 °C, from about 1306 °C to about 1310 °C, or from about 1308 °C to about 1310 °C, including all ranges and sub-ranges therebetween.

[0219] In other embodiments, the glass can include T in the range from about 1290 °C to about 1308 °C, from about 1290 °C to about 1306 °C, from about 1290 °C to about 1304 °C, from about 1290 °C to about 1302 °C, from about 1290 °C to about 1300 °C, from about 1290 °C to about 1298 °C, from about 1290 °C to about 1296 °C, from about 1290 °C to about 1294 °C, or from about 1290 °C to about 1292 °C 35kP , including all ranges and sub-ranges therebetween. In a particular embodiment, T 35kP can be in the range from about 1290 °C to about 1305 °C, including all ranges and sub-ranges therebetween.

[0220] In an embodiment, the glass may have a T in the range from about 1195 °C to about 1270 °C, such as in the range from about 1195 °C to about 1260 °C, from about 1195 °C to about 1250 °C, from about 1195 °C to about 1240 °C, from about 1195 °C to about 1220 °C, or from about 1195 °C to about 1210 °C, including all ranges and sub-ranges therebetween. liq , including all ranges and sub-ranges therebetween.

[0221] In other embodiments, T liq may be in the range from about 1200 °C to about 1270 °C, from about 1210 °C to about 1270 °C, from about 1220 °C to about 1270 °C, from about 1240 °C to about 1270 °C, or from about 1260 °C to about 1270 °C, including all ranges and sub-ranges therebetween.

[0222] The liquidus viscosity of the glass at the liquidus temperature may be in the range from about 69 kP to about 350 kP, such as in the range from about 100 kP to about 350 kP, from about 120 kP to about 350 kP, from about 140 kP to about 350 kP, from about 160 kP to about 350 kP, from about 180 kP to about 350 kP, from about 200 kP to about 350 kP, from about 220 kP to about 350 kP, from about 240 kP to about 350 kP, from about 260 kP to about 350 kP, from about 280 kP to about 350 kP, from about 300 kP to about 350 kP, or from about 320 kP to about 350 kP, including all ranges and sub-ranges therebetween.

[0223] In other embodiments, the glass may include a liquidus viscosity in the range from about 69 kP to about 350 kP, from about 69 kP to about 320 kP, from about 69 kP to about 300 kP, from about 69 kP to about 280 kP, from about 69 kP to about 300 kP, from about 69 kP to about 280 kP, from about 69 kP to about 260 kP, from about 69 kP to about 260 kP, from about 69 kP to about 240 kP, from about 69 kP to about 220 kP, from about 69 kP to about 200 kP, from about 69 kP to about 180 kP, from about 69 kP to about 160 kP, from about 69 kP to about 140 kP, from about 69 kP to about 120 kP, or from about 69 kP to about 100 kP, including all ranges and sub-ranges therebetween.

[0224] The glass may have a in the range from about 29×10 -7 / °C to about 40×10 -7 / °C, from about 29×10 -7 / °C to about 39×10 -7 / °C, from about 29×10 -7 / °C to about 38×10 -7 / °C, from about 29×10 -7 / °C to about 37×10 -7 / °C, from about 29×10 -7 / °C to about 36×10 -7 / °C, from about 29×10 -7 / °C to about 35×10 -7 / °C, from about 29×10 -7 / °C to about 34×10 -7 / °C, from about 29×10 -7 / °C to about 33×10 -7 / °C, from about 29×10 -7 / °C to about 32×10 -7 / °C, from about 29×10 -7 / °C to about 31×10 -7 / °C, or from about 29×10 -7 / °C to about 30×10 -7 / °C, of the linear thermal expansion coefficient (in the temperature range from 0°C to 300°C), including all ranges and sub-ranges therebetween.

[0225] In other embodiments, the glass may include from about 30×10 -7 / °C to about 36×10 -7 / °C, from about 31×10 -7 / °C to about 36×10 -7 / °C, from about 32×10 -7 / °C to about 36×10 -7 / °C, from about 33×10 -7 / °C to about 36×10 -7 / °C, from about 34×10 -7 / °C to about 36×10 -7 / °C, or from about 35×10 -7 / °C to about 36×10 -7 / °C, of the linear thermal expansion coefficient, including all ranges and sub-ranges therebetween.

[0226] The glass may have a range from about 2.5 g / cc 3 to about 2.62 g / cc 3 in the range, from about 2.55 g / cc3 to about 2.62 g / cc 3 or from about 2.6 g / cc 3 to about 2.66 g / cc 3 in the range of densities, including all ranges and sub-ranges therebetween.

[0227] The glass can have an average transmittance in the range from about 60% to about 80%, such as in the range from about 62% to about 80%, from about 64% to about 80%, from about 66% to about 80%, from about 68% to about 80%, from about 70% to about 80%, from about 72% to about 80%, from about 74% to about 80%, from about 76% to about 80%, or from about 78% to about 80%, including all ranges and sub-ranges therebetween.

[0228] One or more other embodiments can relate to a glass comprising SiO in the range from about 66 mol% to about 71 mol%, such as in the range from about 66.5 mol% to about 71 mol%, from about 67 mol% to about 71 mol%, from about 67.5 mol% to about 71 mol%, from about 68 mol% to about 71 mol%, from about 68.5 mol% to about 71 mol%, from about 69 mol% to about 71 mol%, from about 69.5 mol% to about 71 mol%, from about 70 mol% to about 71 mol%, or from about 70.5 mol% to about 71 mol%, based on the molar percentage of the oxide, 2 including all ranges and sub-ranges therebetween.

[0229] The glass can comprise Al in the range from about 9 mol% to about 12 mol%, such as in the range from about 9.5 mol% to about 12 mol%, from about 10 mol% to about 12 mol%, from about 10.5 mol% to about 12 mol%, from about 11 mol% to about 12 mol%, or from about 11.5 mol% to about 12 mol%, 2 O 3 including all ranges and sub-ranges therebetween.

[0230] The glass may include B in the range from about 7 mol% to about 12 mol%, such as in the range from about 7.5 mol% to about 12 mol%, from about 8 mol% to about 12 mol%, from about 8.5 mol% to about 12 mol%, from about 9 mol% to about 12 mol%, from about 9.5 mol% to about 12 mol%, from about 10 mol% to about 12 mol%, from about 10.5 mol% to about 12 mol%, from about 11 mol% to about 12 mol%, or from about 11.5 mol% to about 12 mol%, including all ranges and sub - ranges therebetween. 2 O 3 , including all ranges and sub - ranges therebetween.

[0231] The glass may include MgO in the range from about 0.9 mol% to about 2.0 mol%, such as in the range from about 1 mol% to about 2 mol%, from about 1.2 mol% to about 2 mol%, from about 1.4 mol% to about 2 mol%, from about 1.6 mol% to about 2 mol%, or from about 1.8 mol% to about 2 mol%, including all ranges and sub - ranges therebetween.

[0232] The glass may include CaO in the range from about 7 mol% to about 11.5 mol%, such as in the range from about 7.5 mol% to about 11.5 mol%, from about 8 mol% to about 11.5 mol%, from about 8.5 mol% to about 11.5 mol%, from about 9 mol% to about 11.5 mol%, from about 9.5 mol% to about 11.5 mol%, from about 10 mol% to about 11.5 mol%, from about 10.5 mol% to about 11.5 mol%, or from about 11 mol% to about 11.5 mol%, including all ranges and sub - ranges therebetween.

[0233] The glass may include SrO in the range from about 0.5 mol% to about 1.1 mol%, such as in the range from about 0.6 mol% to about 1.1 mol%, from about 0.7 mol% to about 1.1 mol%, from about 0.8 mol% to about 1.1 mol%, from about 0.9 mol% to about 1.1 mol%, or from about 1 mol% to about 1.1 mol%, including all ranges and sub - ranges therebetween.

[0234] The glass may include BaO in the range from about 0 to about 0.1 mol%. For example, the glass may be free of BaO.

[0235] The glass may include RO (i.e., MgO, CaO, SrO, and / or BaO) such that (MgO + CaO + SrO + BaO) / Al 2 O 3It can be in the range from about 1 to about 1.2, or in the range from about 1 to about 1.1, including all ranges and sub-ranges therebetween.

[0236] The glass can include NiO in the range from about 0.05 mol% to about 0.15 mol%, such as in the range from about 0.075 mol% to about 0.15 mol%, from about 0.1 mol% to about 0.15 mol%, or from about 0.125 mol% to about 0.15 mol%, including all ranges and sub-ranges therebetween.

[0237] The glass can include Co in the range from about 0.01 mol% to about 0.05 mol%, such as in the range from about 0.02 mol% to about 0.05 mol%, from about 0.03 mol% to about 0.05 mol%, or from about 0.04 mol% to about 0.05 mol% 3 O 4 , including all ranges and sub-ranges therebetween.

[0238] The glass can contain Fe in an amount equal to or less than about 0.02 mol%, such as equal to or less than about 0.01 mol% 2 O 3 amount.

[0239] The glass can be free of alkali metal oxides.

[0240] The glass can have an annealing point in the range from about 720 °C to about 750 °C, such as in the range from about 730 °C to about 750 °C, or from about 740 °C to about 750 °C, including all ranges and sub-ranges therebetween. In other embodiments, the glass can have an annealing point in the range from about 720 °C to about 740 °C, or from about 720 °C to about 730 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass can have an annealing point in the range from about 723 °C to about 745 °C, including all ranges and sub-ranges therebetween.

[0241] The glass can include a strain point in the range from about 660 °C to about 700 °C, such as in the range from about 665 °C to about 700 °C, from about 670 °C to about 700 °C, from about 675 °C to about 700 °C, from about 680 °C to about 700 °C, from about 685 °C to about 700 °C, from about 690 °C to about 700 °C, or from about 695 °C to about 700 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass can include a strain point in the range from about 667 °C to about 693 °C, including all ranges and sub-ranges therebetween.

[0242] The glass may include a Young's modulus in the range from about 69 to about 78 GPa, such as in the range from about 69 GPa to about 76 GPa, from about 69 GPa to about 74 GPa, or from about 69 GPa to about 72 GPa, including all ranges and sub-ranges therebetween. In other embodiments, the glass may include a Young's modulus in the range from about 72 GPa to about 78 GPa, from about 74 GPa to about 78 GPa, or from about 76 GPa to about 78 GPa, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may include a Young's modulus in the range from about 81.9 GPa to about 84.4 GPa, including all ranges and sub-ranges therebetween.

[0243] The glass may include a T that is equal to or less than about 1680 °C 200P , such as in the range from about 1590 °C to about 1680 °C, from about 1600 °C to about 1680 °C, from about 1610 °C to about 1680 °C, from about 1620 °C to about 1680 °C, from about 1630 °C to about 1680 °C, from about 1640 °C to about 1680 °C, from about 1650 °C to about 1680 °C, from about 1660 °C to about 1680 °C, from about 1670 °C to about 1680 °C, including all ranges and sub-ranges therebetween.

[0244] In other embodiments, T 200P may be in the range from about 1590 °C to about 1670 °C, from about 1590 °C to about 1660 °C, from about 1590 °C to about 1650 °C, from about 1590 °C to about 1640 °C, from about 1590 °C to about 1630 °C, from about 1590 °C to about 1620 °C, from about 1590 °C to about 1610 °C, or from about 1590 °C to about 1600 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, T 200P may be in the range from about 1590 °C to about 1675 °C.

[0245] In an embodiment, the glass temperature (T at a viscosity of about 35,000 poise 35kP) It can be in the range from about 1210 °C to about 1260 °C, from about 1210 °C to about 1250 °C, from about 1210 °C to about 1240 °C, from about 1210 °C to about 1230 °C, or from about 1210 °C to about 1220 °C, including all ranges and sub-ranges therebetween. In other embodiments, the glass can include T in the range from about 1220 °C to about 1260 °C, from about 1230 °C to about 1260 °C, from about 1240 °C to about 1260 °C, or from about 1250 °C to about 1260 °C 35kP , including all ranges and sub-ranges therebetween. In certain embodiments, T 35kP can be in the range from about 1216 °C to about 1255 °C, including all ranges and sub-ranges therebetween.

[0246] In embodiments, the glass can include T in the range from about 1090 °C to about 1170 °C, such as from about 1090 °C to about 1160 °C, from about 1090 °C to about 1150 °C, from about 1090 °C to about 1140 °C, from about 1090 °C to about 1120 °C, or from about 1090 °C to about 1110 °C liq , including all ranges and sub-ranges therebetween.

[0247] In other embodiments, T liq can be in the range from about 1100 °C to about 1170 °C, from about 1110 °C to about 1170 °C, from about 1120 °C to about 1170 °C, from about 1140 °C to about 1170 °C, or from about 1160 °C to about 1170 °C, including all ranges and sub-ranges therebetween.

[0248] The glass can exhibit a liquidus viscosity in the range from about 200 kP to about 630 kP, such as from about 300 kP to about 630 kP, from about 400 kP to about 630 kP, or from about 500 kP to about 630 kP at the liquidus temperature, including all ranges and sub-ranges therebetween.

[0249] In other embodiments, the glass can include a liquidus viscosity in the range from about 250 kP to about 630 kP, from about 300 kP to about 630 kP, from about 350 kP to about 630 kP, from about 400 kP to about 630 kP, from about 450 kP to about 630 kP, from about 500 kP to about 630 kP, or from about 550 kP to about 630 kP, including all ranges and sub-ranges therebetween.

[0250] The glass exhibits in the range from about 33×10-7 / °C to about 40×10 -7 / °C, ranging from about 33×10 -7 / °C to about 39×10 -7 / °C, ranging from about 33×10 -7 / °C to about 38×10 -7 / °C, ranging from about 33×10 -7 / °C to about 37×10 -7 / °C, ranging from about 33×10 -7 / °C to about 36×10 -7 / °C, ranging from about 33×10 -7 / °C to about 35×10 -7 / °C, ranging from about 33×10 -7 / °C to about 34×10 -7 The linear coefficient of thermal expansion in the range of / °C (in the temperature range from 0°C to 300°C), including all ranges and sub-ranges therebetween.

[0251] In other embodiments, the glass may include in the range from about 34×10 -7 / °C to about 40×10 -7 / °C, ranging from about 35×10 -7 / °C to about 40×10 -7 / °C, ranging from about 36×10 -7 / °C to about 40×10 -7 / °C, ranging from about 37×10 -7 / °C to about 40×10 -7 / °C, ranging from about 38×10 -7 / °C to about 40×10 -7 / °C, or ranging from about 39×10 -7 / °C to about 40×10 -7 / °C, including all ranges and sub-ranges therebetween.

[0252] The glass may have a density in the range from about 2.3 g / cc 3 to about 2.5 g / cc 3 For example, in the range from about 2.35 g / cc 3 to about 2.5 g / cc 3 in the range from about 2.4 g / cc 3 to about 2.5 g / cc 3 in the range from about 2.45 g / cc 3 to about 2.5 g / cc 3 including all ranges and sub-ranges therebetween. In certain embodiments, the glass may include in the range from about 2.34 g / cc3 to about 2.45 g / cc 3 in density in the range of

[0253] The glass can have an average transmittance in the range from about 64% to about 82%, such as in the range from about 64% to about 80%, from about 64% to about 78%, from about 64% to about 76%, from about 64% to about 74%, from about 64% to about 72%, from about 64% to about 70%, from about 64% to about 68%, or from about 64% to about 66%, including all ranges and sub - ranges therebetween.

[0254] In other embodiments, the glass can have an average transmittance in the range from about 66% to about 82%, such as in the range from about 68% to about 82%, from about 70% to about 82%, from about 72% to about 82%, from about 74% to about 82%, from about 76% to about 82%, from about 78% to about 82%, or from about 80% to about 82%, including all ranges and sub - ranges therebetween.

[0255] Other specific embodiments can relate to a glass comprising SiO in the range from about 61 mol% to about 68 mol%, such as in the range from about 61.5 mol% to about 68 mol%, from about 62 mol% to about 68 mol%, from about 62.5 mol% to about 68 mol%, from about 63 mol% to about 68 mol%, from about 63.5 mol% to about 68 mol%, from about 64 mol% to about 68 mol%, from about 64.5 mol% to about 68 mol%, from about 65 mol% to about 68 mol%, from about 65.5 mol% to about 68 mol%, from about 66 mol% to about 68 mol%, from about 66.5 mol% to about 68 mol%, from about 67 mol% to about 68 mol%, or from about 67.5 mol% to about 68 mol% 2 , including all ranges and sub - ranges therebetween.

[0256] The glass can include Al in the range from about 11 mol% to about 14 mol%, such as in the range from about 11.5 mol% to about 14 mol%, from about 12 mol% to about 14 mol%, from about 12.5 mol% to about 14 mol%, from about 13 mol% to about 14 mol%, or from about 13.5 mol% to about 14 mol% 2 O 3 , including all ranges and sub - ranges therebetween.

[0257] The glass may include B in the range from about 6 mol% to about 8.5 mol%, such as in the range from about 6.5 mol% to about 8.5 mol%, from about 7 mol% to about 8.5 mol%, from about 7.5 mol% to about 8.5 mol%, or from about 8 mol% to about 8.5 mol%, including all ranges and sub-ranges therebetween. 2 O 3 , including all ranges and sub-ranges therebetween.

[0258] The glass may include MgO in the range from about 3.5 mol% to about 6.0 mol%, such as in the range from about 4 mol% to about 6.0 mol%, from about 4.5 mol% to about 6.0 mol%, from about 5 mol% to about 6.0 mol%, or from about 5.5 mol% to about 6 mol%, including all ranges and sub-ranges therebetween.

[0259] The glass may include CaO in the range from about 5 mol% to about 7 mol%, such as in the range from about 5.5 mol% to about 7 mol%, from about 6 mol% to about 7 mol%, or from about 6.5 mol% to about 7 mol%, including all ranges and sub-ranges therebetween.

[0260] The glass may include SrO in the range from about 3 mol% to about 5 mol%, such as in the range from about 3.5 mol% to about 5 mol%, from about 4 mol% to about 5 mol%, or from about 4.5 mol% to about 5 mol%, including all ranges and sub-ranges therebetween.

[0261] The glass may include BaO in the range from about 0 to about 0.1 mol%. For example, the glass may be free of BaO.

[0262] The glass may include RO (i.e., MgO, CaO, SrO, and / or BaO) such that (MgO + CaO + SrO + BaO) / Al 2 O 3 may be in the range from about 1.05 to about 1.3, from about 1.1 to about 1.3, or from about 1.2 to about 1.3, including all ranges and sub-ranges therebetween.

[0263] The glass may be substantially free of alkali metal oxides.

[0264] The glass may have an annealing point in the range from about 700 °C to about 760 °C, such as in the range from about 700 °C to about 750 °C, from about 700 °C to about 740 °C, from about 700 °C to about 730 °C, from about 700 °C to about 720 °C, from about 700 °C to about 710 °C, including all ranges and sub-ranges therebetween.

[0265] The glass may include NiO in the range from about 0.05 mol% to about 0.15 mol%, such as in the range from about 0.075 mol% to about 0.15 mol%, from about 0.1 mol% to about 0.15 mol%, or from about 0.125 mol% to about 0.15 mol%, including all ranges and sub-ranges therebetween.

[0266] The glass may include Co in the range from about 0.01 mol% to about 0.05 mol%, such as in the range from about 0.02 mol% to about 0.05 mol%, from about 0.03 mol% to about 0.05 mol%, or from about 0.04 mol% to about 0.05 mol% 3 O 4 , including all ranges and sub-ranges therebetween.

[0267] The glass may contain Fe in an amount equal to or less than about 0.02 mol%, such as equal to or less than about 0.01 mol% 2 O 3 .

[0268] The glass may be free of alkali metal oxides.

[0269] In other embodiments, the glass may have an annealing point in the range from about 710 °C to about 760 °C, from about 720 °C to about 760 °C, from about 730 °C to about 760 °C, from about 740 °C to about 760 °C, or from about 750 °C to about 760 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may have an annealing point in the range from about 713 °C to about 754 °C, including all ranges and sub-ranges therebetween.

[0270] The glass may include a strain point in the range from about 670 °C to about 710 °C, such as in the range from about 675 °C to about 710 °C, from about 680 °C to about 710 °C, from about 685 °C to about 710 °C, from about 690 °C to about 710 °C, or from about 700 °C to about 710 °C, including all ranges and sub-ranges therebetween.

[0271] In other embodiments, the glass may include a strain point in the range from about 670 °C to about 700 °C, from about 670 °C to about 690 °C, or from about 670 °C to about 680 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may include a strain point in the range from about 676 °C to about 701 °C, including all ranges and sub-ranges therebetween.

[0272] The glass may have a Young's modulus in the range from about 75 to about 81 GPa, such as in the range from about 76 GPa to about 81 GPa, from about 77 GPa to about 81 GPa, from about 78 GPa to about 81 GPa, or from about 79 GPa to about 81 GPa, including all ranges and sub-ranges therebetween. In other embodiments, the glass may have a Young's modulus in the range from about 75 GPa to about 79 GPa, from about 75 GPa to about 78 GPa, from about 75 GPa to about 77 GPa, or from about 75 GPa to about 76 GPa, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may have a Young's modulus in the range from about 78.8 GPa to about 80.6 GPa, including all ranges and sub-ranges therebetween.

[0273] The glass may have a T that is equal to or less than about 1680 °C 200P , such as in the range from about 1530 °C to about 1610 °C, from about 1530 °C to about 1600 °C, from about 1530 °C to about 1590 °C, from about 1530 °C to about 1580 °C, from about 1530 °C to about 1570 °C, from about 1530 °C to about 1560 °C, from about 1530 °C to about 1550 °C, or from about 1530 °C to about 1540 °C, including all ranges and sub-ranges therebetween.

[0274] In other embodiments, the T 200P may be in the range from about 1540 °C to about 1610 °C, from about 1550 °C to about 1610 °C, from about 1560 °C to about 1610 °C, from about 1570 °C to about 1610 °C, from about 1580 °C to about 1610 °C, or from about 1590 °C to about 1610 °C, including all ranges and sub-ranges therebetween. In a particular embodiment, the T 200P may be in the range from about 1530 °C to about 1606 °C, including all ranges and sub-ranges therebetween.

[0275] In an embodiment, the glass temperature (T at a viscosity of about 35,000 poise 35kP)It can be in the range from about 1170 °C to about 1240 °C, from about 1180 °C to about 1240 °C, from about 1200 °C to about 1240 °C, from about 1210 °C to about 1240 °C, from about 1220 °C to about 1240 °C, or from about 1230 °C to about 1240 °C, including all ranges and sub - ranges therebetween. In other embodiments, the glass can be included in the range from about 1170 °C to about 1230 °C, from about 1170 °C to about 1220 °C, from about 1170 °C to about 1210 °C, from about 1170 °C to about 1200 °C, from about 1170 °C to about 1190 °C, or from about 1170 °C to about 1180 °C for T 35kP , including all ranges and sub - ranges therebetween. In certain embodiments, T 35kP can be in the range from about 1179 °C to about 1237 °C, including all ranges and sub - ranges therebetween.

[0276] In embodiments, the glass can have a T in the range from about 1125 °C to about 1155 °C, such as from about 1125 °C to about 1150 °C, from about 1125 °C to about 1145 °C, from about 1125 °C to about 1140 °C, from about 1125 °C to about 1135 °C, or from about 1125 °C to about 1130 °C liq , including all ranges and sub - ranges therebetween.

[0277] In other embodiments, T liq can be in the range from about 1130 °C to about 1155 °C, from about 1135 °C to about 1155 °C, from about 1140 °C to about 1155 °C, from about 1145 °C to about 1155 °C, or from about 1150 °C to about 1155 °C, including all ranges and sub - ranges therebetween.

[0278] The glass can exhibit a liquidus viscosity in the range from about 120 kP to about 270 kP, such as from about 160 kP to about 270 kP, from about 200 kP to about 270 kP, or from about 250 kP to about 270 kP at the liquidus temperature, including all ranges and sub - ranges therebetween. In other embodiments, the glass can include a liquidus viscosity in the range from about 120 kP to about 250 kP, from about 120 kP to about 200 kP, or from about 120 kP to about 160 kP, including all ranges and sub - ranges therebetween.

[0279] The glass can have a value in the range from about 33×10 -7 / °C to about 40×10 -7 / °C, or from about 33×10 -7 / °C to about 39×10 -7 / °C, from about 33×10 -7 / °C to about 38×10 -7 / °C, from about 33×10 -7 / °C to about 37×10 -7 / °C, from about 33×10 -7 / °C to about 36×10 -7 / °C, from about 33×10 -7 / °C to about 35×10 -7 / °C, or from about 33×10 -7 / °C to about 34×10 -7 / °C, the coefficient of linear thermal expansion (in the temperature range from 0°C to 300°C), including all ranges and sub-ranges therebetween. In other embodiments, the glass may include a coefficient of thermal expansion in the range from about 34×10 -7 / °C to about 35×10 -7 / °C, including all ranges and sub-ranges therebetween.

[0280] The glass may have a density in the range from about 2.45 g / cc 3 to about 2.52 g / cc 3 such as in the range from about 2.47 g / cc 3 to about 2.52 g / cc 3 or in the range from about 2.49 g / cc 3 to about 2.52 g / cc 3 including all ranges and sub-ranges therebetween. In certain embodiments, the glass may include a density in the range from about 2.48 g / cc 3 to about 2.51 g / cc 3

[0281] ​The glass can have an average transmittance in the range from about 63% to about 80%, such as in the range from about 63% to about 78%, from about 63% to about 76%, from about 63% to about 74%, from about 63% to about 72%, from about 63% to about 70%, from about 63% to about 68%, or from about 63% to about 66%, including all ranges and sub - ranges therebetween. In other embodiments, the glass can have an average transmittance in the range from about 66% to about 80%, from about 68% to about 80%, from about 70% to about 80%, from about 72% to about 80%, from about 74% to about 80%, or from about 76% to about 80%, from about 78% to about 80%, including all ranges and sub - ranges therebetween.

[0282] One or more other embodiments of the present disclosure can relate to a glass that includes SiO in the range from about 66 mol% to about 69 mol%, such as in the range from about 66.5 mol% to about 69 mol%, from about 67 mol% to about 69 mol%, from about 67.5 mol% to about 69 mol%, from about 68 mol% to about 69 mol%, or from about 68.5 mol% to about 69 mol% 2 , including all ranges and sub - ranges therebetween.

[0283] The glass can include Al₂O₃ in the range from about 12 mol% to about 14 mol%, such as in the range from about 12.2 mol% to about 14 mol%, from about 12.4 mol% to about 14 mol%, such as in the range from about 12.6 mol% to about 14 mol%, from about 12.8 mol% to about 14 mol%, such as in the range from about 13 mol% to about 14 mol%, from about 13.2 mol% to about 14 mol%, from about 13.4 mol% to about 14 mol%, from about 13.6 mol% to about 14 mol%, or from about 13.8 mol% to about 14 mol% 2 O₃ 3 , including all ranges and sub - ranges therebetween.

[0284] The glass can further include B₂O₃ in the range from about 4 mol% to about 5 mol%, such as in the range from about 4.2 mol% to about 5 mol%, from about 4.4 mol% to about 5 mol%, from about 4.6 mol% to about 5 mol%, or from about 4.8 mol% to about 5 mol% 2 O₃ 3 , including all ranges and sub - ranges therebetween.

[0285] The glass may further include MgO in the range from about 4 mol% to about 6 mol%, such as in the range from about 4.2 mol% to about 6 mol%, from about 4.4 mol% to about 6 mol%, from about 4.6 mol% to about 6 mol%, from about 4.8 mol% to about 6 mol%, from about 5 mol% to about 6 mol%, from about 5.2 mol% to about 6 mol%, from about 5.4 mol% to about 6 mol%, from about 5.6 mol% to about 6 mol%, or from about 5.8 mol% to about 6 mol%. In other embodiments, the glass may include an amount of MgO in the range from about 4 mol% to about 5.8 mol%, from about 4 mol% to about 5.6 mol%, from about 4 mol% to about 5.4 mol%, from about 4 mol% to about 5.2 mol%, from about 4 mol% to about 5 mol%, from about 4 mol% to about 4.8 mol%, from about 4 mol% to about 4.6 mol%, from about 4 mol% to about 4.4 mol%, or from about 4 mol% to about 4.2 mol%, including all ranges and sub-ranges therebetween. In other embodiments, the glass may include MgO in the range from about 4.2 mol% to about 5.8 mol%, from about 4.4 mol% to about 5.6 mol%, from about 4.6 mol% to about 5.4 mol%, or from about 4.8 mol% to about 5.2 mol%, including all ranges and sub-ranges therebetween. In certain embodiments, the glass may include MgO in the range from about 4.5 mol% to about 5.3 mol%, including all ranges and sub-ranges therebetween.

[0286] The glass may include CaO in the range from about 5 mol% to about 7 mol%, such as in the range from about 5.2 mol% to about 7 mol%, from about 5.4 mol% to about 7 mol%, from about 5.6 mol% to about 7 mol%, from about 5.8 mol% to about 7 mol%, from about 6 mol% to about 7 mol%, from about 6.2 mol% to about 7 mol%, from about 6.4 mol% to about 7 mol%, from about 6.6 mol% to about 7 mol%, or from about 6.8 mol% to about 7 mol%, including all ranges and sub-ranges therebetween.

[0287] In other embodiments, the glass may include CaO in the range from about 5 mol% to about 6.8 mol%, from about 5 mol% to about 6.6 mol%, from about 5 mol% to about 6.4 mol%, from about 5 mol% to about 6.2 mol%, from about 5 mol% to about 6 mol%, from about 5 mol% to about 5.8 mol%, from about 5 mol% to about 5.6 mol%, from about 5 mol% to about 5.4 mol%, or from about 5 mol% to about 5.2 mol%, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may include CaO in the range from about 5.5 mol% to about 6.5 mol%, including all ranges and sub-ranges therebetween.

[0288] The glass may include SrO in the range from about 1.25 mol% to about 3.6 mol%, such as from about 1.5 mol% to about 3.6 mol%, from about 1.75 mol% to about 3.6 mol%, from about 2 mol% to about 3.6 mol%, from about 2.25 mol% to about 3.6 mol%, from about 2.5 mol% to about 3.6 mol%, from about 2.75 mol% to about 3.6 mol%, from about 3 mol% to about 3.6 mol%, or from about 3.25 mol% to about 3.6 mol%, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may include SrO in the range from about 1.5 mol% to about 3.6 mol%, including all ranges and sub-ranges therebetween.

[0289] The glass may include BaO in the range from about 0.5 mol% to about 2 mol%, such as from about 0.75 mol% to about 2 mol%, from about 1 mol% to about 2 mol%, from about 1.25 mol% to about 2 mol%, from about 1.5 mol% to about 2 mol%, or from about 1.75 mol% to about 2 mol%, including all ranges and sub-ranges therebetween. In a particular embodiment, the glass may include BaO in the range from about 0.7 mol% to about 1.8 mol%, including all ranges and sub-ranges therebetween.

[0290] The glass may include RO (i.e., MgO, CaO, SrO, and / or BaO) such that (MgO + CaO + SrO + BaO) / Al 2 O 3 may be in the range from about 1.10 to about 1.14, from about 1.12 to about 1.14, or from about 1.13 to about 1.14, including all ranges and sub-ranges therebetween.

[0291] The glass may include NiO in the range from about 0.05 mol% to about 0.15 mol%, such as in the range from about 0.075 mol% to about 0.15 mol%, from about 0.1 mol% to about 0.15 mol%, or from about 0.125 mol% to about 0.15 mol%, including all ranges and sub - ranges therebetween.

[0292] The glass may include Co in the range from about 0.01 mol% to about 0.05 mol%, such as in the range from about 0.02 mol% to about 0.05 mol%, from about 0.03 mol% to about 0.05 mol%, or from about 0.04 mol% to about 0.05 mol% 3 O 4 , including all ranges and sub - ranges therebetween.

[0293] The glass may contain Fe in an amount equal to or less than about 0.02 mol%, such as equal to or less than about 0.01 mol% 2 O 3 amount.

[0294] The glass may be substantially free of alkali metal oxides.

[0295] The glass may have an annealing point in the range from about 760 °C to about 765 °C, such as in the range from about 763 °C to about 765 °C.

[0296] The glass may include a strain point in the range from about 700 °C to about 720 °C, such as in the range from about 710 °C to about 720 °C, including all ranges and sub - ranges therebetween.

[0297] The glass may include a Young's modulus in the range from about 75 to about 83 GPa, such as in the range from about 76 GPa to about 83 GPa, from about 78 GPa to about 83 GPa, or from about 80 GPa to about 83 GPa, including all ranges and sub - ranges therebetween. In other embodiments, the glass may include a Young's modulus in the range from about 75 GPa to about 80 GPa, from about 75 GPa to about 78 GPa, or from about 75 GPa to about 76 GPa, including all ranges and sub - ranges therebetween. In certain embodiments, the glass may include a Young's modulus in the range from about 78.3 GPa to about 82.4 GPa, including all ranges and sub - ranges therebetween.

[0298] The glass may have a T equal to or less than about 1680 °C 200P, for example, in the range from about 1600 °C to about 1680 °C, from about 1610 °C to about 1680 °C, from about 1620 °C to about 1680 °C, or from about 1630 °C to about 1680 °C, from about 1640 °C to about 1680 °C, from about 1650 °C to about 1680 °C, from about 1660 °C to about 1680 °C, or from about 1670 °C to about 1680 °C, including all ranges and sub - ranges therebetween. In other embodiments, T 200P can be in the range from about 1600 °C to about 1670 °C, from about 1600 °C to about 1660 °C, from about 1600 °C to about 1650 °C, from about 1600 °C to about 1640 °C, or from about 1600 °C to about 1630 °C, including all ranges and sub - ranges therebetween. In certain embodiments, T 200P can be in the range from about 1608 °C to about 1639 °C, including all ranges and sub - ranges therebetween.

[0299] In an embodiment, the glass transition temperature (T 35kP ) at a viscosity of about 35,000 poise can be in the range from about 1230 °C to about 1270 °C, from about 1240 °C to about 1270 °C, from about 1250 °C to about 1270 °C, or from about 1260 °C to about 1270 °C, including all ranges and sub - ranges therebetween. In other embodiments, the glass can include T 35kP in the range from about 1230 °C to about 1260 °C, from about 1230 °C to about 1250 °C, or from about 1230 °C to about 1240 °C, including all ranges and sub - ranges therebetween. In certain embodiments, T 35kP can be in the range from about 1238 °C to about 1264 °C, including all ranges and sub - ranges therebetween.

[0300] In an embodiment, the glass can have a T liq in the range from about 1135 °C to about 1185 °C, such as from about 1135 °C to about 1175 °C, from about 1135 °C to about 1165 °C, from about 1135 °C to about 1155 °C, or from about 1135 °C to about 1145 °C, including all ranges and sub - ranges therebetween. In other embodiments, T liq can be in the range from about 1145 °C to about 1185 °C, from about 1155 °C to about 1185 °C, from about 1165 °C to about 1185 °C, or from about 1175 °C to about 1185 °C, including all ranges and sub - ranges therebetween.

[0301] The glass can exhibit a liquidus viscosity in the range from about 200 kP to about 390 kP, such as in the range from about 250 kP to about 390 kP, from about 300 kP to about 390 kP, or from about 350 kP to about 390 kP, including all ranges and sub - ranges therebetween. In other embodiments, the glass can include a liquidus viscosity in the range from about 200 kP to about 350 kP, from about 200 kP to about 300 kP, or from about 200 kP to about 250 kP, including all ranges and sub - ranges therebetween.

[0302] The glass can have a linear thermal expansion coefficient (in the temperature range from 0 °C to 300 °C) in the range from about 33×10 -7 / °C to about 40×10 -7 / °C, from about 33×10 -7 / °C to about 39×10 -7 / °C, from about 33×10 -7 / °C to about 38×10 -7 / °C, from about 33×10 -7 / °C to about 37×10 -7 / °C, from about 33×10 -7 / °C to about 36×10 -7 / °C, from about 33×10 -7 / °C to about 35×10 -7 / °C, or from about 33×10 -7 / °C to about 34×10 -7 / °C, including all ranges and sub - ranges therebetween. In other embodiments, the glass can include a thermal expansion coefficient in the range from about 34×10 -7 / °C to about 40×10 -7 / °C, from about 35×10 -7 / °C to about 40×10 -7 / °C, from about 36×10 -7 / °C to about 40×10 -7 / °C, from about 37×10 -7 / °C to about 40×10 -7 / °C, from about 38×10 -7 / °C to about 40×10 -7 / °C, or from about 39×10 -7 / °C to about 40×10 -7 / °C, including all ranges and sub - ranges therebetween.

[0303] The glass can have a density in the range from about 2.5 g / cc 3to about 2.6 g / cc 3 in the range of, e.g., from about 2.52 g / cc 3 to about 2.6 g / cc 3 in the range of, from about 2.54 g / cc 3 to about 2.6 g / cc 3 in the range of, from about 2.56 g / cc 3 to about 2.6 g / cc 3 in the range of, or from about 2.58 g / cc 3 to about 2.6 g / cc 3 in the range of densities, including all ranges and sub-ranges therebetween. In certain embodiments, the glass can include a density in the range from about 2.52 g / cc 3 to about 2.54 g / cc 3 .

[0304] The glass can have an average transmittance in the range from about 63% to about 80%, e.g., in the range from about 63% to about 78%, from about 63% to about 76%, from about 63% to about 74%, from about 63% to about 72%, from about 63% to about 70%, from about 63% to about 68%, or from about 63% to about 66%, including all ranges and sub-ranges therebetween. In other embodiments, the glass can have an average transmittance in the range from about 66% to about 80%, from about 68% to about 80%, from about 70% to about 80%, from about 72% to about 80%, from about 74% to about 80%, or from about 76% to about 80%, from about 78% to about 80%, including all ranges and sub-ranges therebetween.

[0305] Exemplary glasses with reduced optical transmittance are listed in Tables 1-5 below. All glass compositions are listed in mole percentages (mol%) of oxides. The glass is melted and formed into a glass sheet with a thickness of 0.7 mm. The glass includes the addition of transition metal oxides, particularly NiO and Co 3 O 4 to reduce the optical transmittance of the glass. The optical transmittance is measured with a power meter. Figure 6 is a graph of the optical transmittance of glasses S1-S9 from Table 1.

[0306] Table 1

[0307]

[0308] Table 2

[0309]

[0310]

[0311] Table 3

[0312]

[0313] Table 4

[0314]

[0315]

[0316] Table 5

[0317]

[0318]

[0319] The glass compositions listed in Tables 1-5 can be determined using quantitative analysis techniques well known in the art. Suitable techniques are X-ray fluorescence spectrometry (XRF) for elements with atomic number higher than 8, inductively coupled plasma optical emission spectrometry (ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and electron microprobe analysis. See, for example, J. Nolte, ICP Emission Spectrometry: A Practical Guide ( ICP Emission Spectrometry: A Practical Guide ), Wiley-VCH (2003); H.E. Taylor, Inductively Coupled Plasma Mass Spectroscopy: Practices and Techniques ( Inductively Coupled Plasma Mass Spectroscopy: Practices and Techniques ), Academic Press (2000); and S.J.B. Reed, Electron Microprobe Analysis ( Electron Microprobe Analysis ), Cambridge University Press; 2nd ed. (1997), which are hereby incorporated by reference.

[0320] The glass properties listed in Tables 1-5 are determined according to conventional techniques in the glass art. Thus, the coefficient of linear thermal expansion (CTE) in the temperature range of 0 - 300 °C is expressed in ×10 -7 / °C, and the annealing point and strain point are expressed in °C. These are determined by fiber elongation techniques (refer to ASTM E228-85 and C336, respectively). The density in g / cm 3 is measured via the Archimedes method (ASTM C693). The melting temperature (defined as the temperature T 200P at which the glass melt exhibits a viscosity of 200 poise) expressed in °C is calculated using the Fulcher equation, which is suitable for high-temperature viscosity data measured via rotational cylinder viscometry (ASTM C965-81).

[0321] The liquidus temperature of the glass in °C is measured using the standard gradient boat liquidus method of ASTM C829-81. This involves placing crushed glass particles in a platinum boat, placing the boat in a furnace having a temperature gradient zone, heating the boat in a suitable temperature zone for 24 hours, and determining the highest temperature at which crystals appear within the glass by means of microscopic examination. More particularly, the glass sample is removed intact from the platinum boat and examined using polarized light microscopy to identify the location and nature of the crystals formed at the platinum and air interface and within the sample. Since the gradient of the furnace is well known, the temperature versus position relationship can be well estimated within a range of 5-10 °C. The temperature at which crystals are observed within the sample represents the liquidus of the glass (corresponding test cycle). The test is sometimes carried out for a longer time (e.g., 72 hours) to observe slower growth stages. The liquidus viscosity in poise is determined from the liquidus temperature and the coefficients of the Fulcher equation.

[0322] The value of Young's modulus in GPa is determined using the general type of resonant ultrasonic spectroscopy technique presented in ASTM E1875-00e1.

[0323] Raw materials suitable for producing the exemplary glasses disclosed herein include: commercially available sand as a source of SiO 2 ; alumina, aluminum hydroxide, hydrated forms of alumina and various aluminosilicates, nitrates and halides as a source of Al 2 O 3 ; boric acid, anhydrous boric acid and boron oxide as a source of B 2 O 3 ; periclase, dolomite (also a source of CaO), magnesia, magnesium carbonate, magnesium hydroxide and various forms of magnesium silicate, aluminosilicate, nitrate and halide as a source of MgO; limestone, aragonite, dolomite (also a source of MgO), wollastonite and various forms of calcium silicate, aluminosilicate, nitrate and halide as a source of CaO; and oxides, carbonates, nitrates and halides of strontium and barium. If a chemical clarifier is required, tin can be added as SnO 2 , as a mixed oxide with another major glass component (e.g., CaSnO 3 ), or added as SnO, tin oxalate, tin halide or other tin compounds known to those skilled in the art under oxidizing conditions.

[0324] Almost all of the stable elements in the periodic table are present in glass at some level, either through low-level contamination in the raw materials, or through high-temperature erosion of refractories and noble metals during the manufacturing process, or through the intentional introduction of low-level elements to fine-tune the properties of the final glass, in addition to the elements intentionally incorporated into the exemplary glass. For example, zirconium may be introduced as a contaminant via interaction with zirconium-rich refractories. As another example, platinum and rhodium may be introduced via interaction with noble metals incorporated into the glass manufacturing apparatus. As another example, iron may be introduced as an impurity component in the raw materials or intentionally added to enhance control of gaseous inclusions. As another example, manganese may be introduced to control color or enhance control of gas inclusions. As another example, for the combined concentration of Li 2 O, Na 2 O, and K 2 O, the alkali metals may be present as an impurity component at levels up to about 0.1 mole %.

[0325] Hydrogen inevitably exists in the form of the hydroxyl anion OH - , and its presence can be determined via standard infrared spectroscopic techniques. Dissolved hydroxyl ions significantly and non-linearly affect the annealing point of the exemplary glass, and thus, in order to obtain the desired annealing point, it may be necessary to adjust the concentration of the major oxide components to compensate. The concentration of hydroxyl ions can be controlled to some extent by selecting the raw materials or selecting the melting system. For example, boric acid is a major source of hydroxyls, and replacing boric acid with boron oxide may be an effective means of controlling the hydroxyl concentration in the final glass. The same reasoning applies to other potential raw materials that include hydroxyl ions, hydrates, or compounds that include physically or chemically adsorbed water molecules. If burners are used during the melting process, then hydroxyl ions can also be introduced via the combustion products of natural gas and related hydrocarbons, and thus it may be desirable to transfer the energy used in melting from burners to electrodes for compensation. Alternatively, an iterative process of adjusting the major oxide components can be employed to compensate for the detrimental effects of dissolved hydroxyl ions.

[0326] Sulfur is typically present in natural gas and is also an impurity component in many carbonate, nitrate, halide, and oxide raw materials. In the form of SO 2 , sulfur can be a troublesome source of gaseous inclusions. By controlling the sulfur content in the raw materials, and by incorporating low levels of relatively reduced multivalent cations into the glass matrix, the tendency to form defects rich in SO 2 can be controlled to a large extent. While not wishing to be bound by theory, it seems that gaseous inclusions rich in SO 2 are primarily formed by the dissolution of sulfates (SO 4 ＝) is caused by the reduction. The increase in the barium concentration in the exemplary glass seems to increase the sulfur retention in the glass during the early stage of melting. However, as mentioned above, barium is used to obtain a low liquidus temperature and thus a high T 35k -T liq and a high liquidus viscosity. Intentionally controlling the sulfur content in the raw materials at a low level is an effective way to reduce the dissolved sulfur (presumably sulfate) in the glass. In particular, the sulfur in the batch is preferably less than 200 ppm by weight, and more preferably less than 100 ppm by weight in the batch.

[0327] Reduced polyvalent oxides can also be used to control the tendency of the exemplary glass to form SO 2 bubbles. Although not wishing to be bound by theory, these elements act as potential electron donors, inhibiting the electromotive force of sulfate reduction. Sulfate reduction can be written as a half-reaction, such as

[0328] SO 4 ＝ →SO 2 +O 2 +2e - (2)

[0329] where e - represents an electron. The "equilibrium constant" of the half-reaction is

[0330] K eq =[SO 2 [O 2 [e - 2 / [SO 4 ＝ (3)

[0331] where the brackets represent chemical activity. Ideally, one would like to drive the reaction and produce sulfate from SO 2 、O 2 and 2e - . Adding nitrates, peroxides or other oxygen-rich raw materials may help, but may also hinder sulfate reduction in the early stage of melting, which may offset the benefits of initially adding them. The solubility of SO 2 in most glasses is very low, so adding it to the glass melting process is impracticable. Electrons can be "added" through reduced polyvalents. For example, the appropriate electron-donating half-reaction of ferrous (Fe 2+ ) is represented as

[0332] 2Fe 2+ →2Fe 3+ +2e - . (4)

[0333] ​This "activity" of the electrons can force the sulfate reduction reaction to the left, stabilizing the SO in the glass 4 ＝ . Suitable reducing polyvalent ions include, but are not limited to, Fe 2+ , Mn 2+ , Sn 2+ , Sb 3+ , As 3+ , V 3+ , Ti 3+ and other ions familiar to those skilled in the art. In each case, it is important to minimize the concentration of such components to avoid deleterious effects on the color of the glass or, in the case of As and Sb, to avoid adding such components at levels high enough to complicate waste management in end-user processes.

[0334] In addition to the major oxide components of the exemplary glass and the minor or impurity components described above, halides can be present at various levels, either as contaminants introduced through the selection of raw materials or as intentional components used to eliminate gaseous inclusions in the glass. Halides can be incorporated as fining agents at levels of about 0.4 mole % or less, although lower amounts are generally desired to avoid corrosion of the exhaust treatment equipment. In some embodiments, for each individual halide, the concentration of the individual halide element is less than about 200 ppm by weight, or for the sum of all halide elements, less than about 800 ppm by weight.

[0335] Now referring to Figure 7 and Figure 8 , a top view and a simplified cross-sectional view of another exemplary large area display 100 are depicted, respectively. The large area display 100 includes a substrate 102 and a plurality of small displays 104 disposed on the substrate 102. Each small display 104 can be a micro-LED display, such as a top-emitting micro-LED display or a bottom-emitting micro-LED display. Between the edges of adjacent small displays 104 are seams 106. As described in more detail below with reference to Figures 9 - 11 , light emitted from the small displays 104 may leak from the edges of the small displays at the seams 106, resulting in visible seams when the large area display 100 is turned on.

[0336] The substrate 102 can be a glass substrate, a printed circuit board, or another suitable substrate that includes circuitry for routing power and signals to each of the micro-LEDs of each small display 104 to control the operation of each small display 104. The substrate 102 can be attached to the small displays 104, for example, using fasteners and / or adhesive materials. Although in the described embodiment, the large-area display 100 includes 16 small displays 104 arranged in four rows and four columns, in other embodiments, the large-area display 100 can include any suitable number of small displays 104 arranged in any suitable number of rows and columns.

[0337] Figure 9 is a top view of an exemplary small display 104. The small display 104 includes a bottom plate 202 and a plurality of pixels 204 electrically coupled to the bottom plate 202. Each pixel 204 can include one, two, three, four, or more micro-LEDs to provide a monochromatic or color display. The bottom plate 202 can be a glass substrate or a printed circuit board that includes circuitry for routing power and signals to each pixel 204 to control the operation of each micro-LED of each pixel 204. The small display 104 includes four edges 203 from which light emitted by the display pixels can leak. Although in the described embodiment, the small display 104 includes 23 rows and 13 columns of pixels 204, in other embodiments, the small display 104 can include any suitable number of pixel rows and columns.

[0338] Figure 10 and Figure 11 is Figure 9Simplified cross-sectional view of an exemplary small display 104. In addition to the bottom plate 202 and the pixels 204, the small display 104 includes an optically clear adhesive (OCA) layer 206 and a glass layer (e.g., a glass cover plate) 208. As used herein, an optically clear adhesive is an adhesive located in the optical path, having a defined refractive index, high transmittance, and forming a reliable bond between components. In this example, each pixel 204 includes a first (e.g., blue) micro-LED 204a, a second (e.g., green) micro-LED 204b, and a third (e.g., red) micro-LED 204c to provide a full-color display. Thus, the small display 104 includes micro-LEDs electrically coupled to the bottom plate 202. Each micro-LED 204a, 204b, 204c is electrically coupled to a circuit (not shown) on the bottom plate 202 for controlling the operation of each micro-LED. In this embodiment, the plurality of micro-LEDs are top-emitting micro-LEDs such that most of the light emitted by the micro-LEDs passes through the top of the small display 104. In an embodiment, the bottom plate 202 may include a glass substrate on which a thin-film transistor (TFT) array is formed, and each TFT is electrically coupled to the micro-LED. In other embodiments, the bottom plate 202 may include a printed circuit board or another suitable substrate.

[0339] The OCA layer 206 may include phenyl silicone or another suitable material, such as Norland Optical Adhesive 60 available from Norland Products Inc., Jamesburg, NJ, USA, Dymax OP-60 available from Dymax Corporation, Torrington, CT, USA, or NTTGA700H available from NTT Advanced Technology Corporation, Tokyo, Japan. The OCA layer 206 is located near (e.g., above) the bottom plate 202 and the plurality of micro-LEDs (204a, 204b, 204c), for example, directly contacting the top surface 210 of the bottom plate 202 and directly contacting and encapsulating the plurality of micro-LEDs. The glass layer 208 may include glass, such as aluminosilicate, alkali metal aluminosilicate, borosilicate, alkali metal borosilicate, aluminoborosilicate, alkali metal aluminoborosilicate, soda lime, or other suitable glass (e.g., glass, Ceramic Shield, EAGLE Glass). The glass layer 208 is close to the OCA layer 206 (e.g., above it), and directly contacts, for example, the top surface 212 of the OCA layer 206. The glass layer 208 can be laminated to the bottom plate 202 and the plurality of micro-LEDs via the OCA layer 206 to protect the micro-LEDs and enhance the mechanical properties of the small display 104.

[0340] The OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 203 of the small display 104 by several different mechanisms. As Figure 10 shown in 216a, a first way that the OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 203 of the small display 104 includes: light that escapes from the sidewall of the micro-LED and exits directly from the edge of the OCA layer 206 and / or the glass layer 208. Since the OCA layer 206 has a higher refractive index than air compared to a display without the OCA layer 206 and the glass layer 208, more light is emitted from the sidewalls of the micro-LEDs in a display including the OCA layer 206 and the glass layer 208. Therefore, the OCA layer 206 and the glass layer 208 enhance edge light leakage. As Figure 10 shown in 216b, a second way that the OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 203 of the small display 104 includes: light that escapes from the sidewall of the micro-LED and first reaches the top surface 218 of the glass layer 208 is reflected by the interface between air and the glass layer 208 (e.g., mainly by total internal reflection (TIR)), and then exits from the edge 203 of the display.

[0341] As Figure 11 shown in 216c, a third way that the OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 203 of the small display 104 includes: light emitted from the top surface of the micro-LED exits directly from the edge 203 of the OCA layer 206 and the glass layer 208. As Figure 11 shown in 216d, a fourth way that the OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 302 of the small display 104 includes: light emitted from the top surface of the micro-LED and first reaching the top surface 216 of the glass layer 208 is reflected by the interface between air and the glass layer 208 (e.g., mainly by TIR), and then exits from the edge 203 of the small display 104.

[0342] Other phenomena that can be mitigated by using the glass with reduced transmittance described herein include halos or veiling glare, which are particularly evident in local dimming displays (such as full array local dimming LCD displays). Full array local dimming displays have LEDs located behind the entire display panel; the LEDs are divided into local dimming zones. To depict a bright zone in one area of the display, the LEDs in the area behind the bright zone are turned on, while the LEDs in the surrounding areas are dimmed or turned off. When light from the isolated bright areas of the display leaks into the surrounding darker areas, a halo effect occurs. This can result in muddy blacks.

[0343] In almost the same way, the glass with reduced transmittance can be used to mitigate light leakage in bottom-emitting display devices, and the glass with reduced transmittance can be used to mitigate light leakage from top-emitting display devices. That is, when the glass is used as a protective glass plate, the light leaking from the light emitter (e.g., internal reflection and / or edge emission from the light emitter), which typically intersects the glass cover plate at an oblique angle with respect to the main surface of the glass cover plate, can reduce the intensity of the leaked light and increase the contrast. The light directly transmitted from the light emitter is attenuated less than the leaked light because the propagation distance of the light through the glass is less than that of the obliquely transmitted light. In an embodiment, the protective glass plate can be directly laminated (without an air gap) to the light emitter bottom substrate, e.g., via an OCA layer. These phenomena are not limited to tiled displays.

[0344] Accordingly, a display configured to suppress unwanted light emitted from a self-emitting display (e.g., a micro-LED display) and an LCD display is disclosed herein. The display can include an OCA layer 206 and a glass layer 208, wherein unwanted light can be mitigated by adjusting the geometric design (e.g., the thickness of the glass layer 208 and / or the OCA layer 206) and optical properties (e.g., refractive index and transmittance (or absorptance)) of the glass layer 208 and / or the OCA layer 206. By considering the edge light leakage suppression perpendicular to the display and the performance of the display brightness, the optimal design can be determined through ray tracing modeling. The transmittance and refractive index of the OCA and glass layers can be adjusted by adjusting the material properties of the OCA and glass layers.

[0345] In an embodiment, as described below with reference to Figure 10 and Figure 11Further described, in order to suppress edge light leakage from the small display 104, the OCA layer 206 may have a thickness 220 between the top surface 210 of the bottom plate 202 and the top surface 212 of the OCA layer 206 in the range from about 0.005 mm to about 0.2 mm, a transmittance in the range from about 40% to about 99.9% (at an OCA layer thickness of about 550 nm), and a refractive index in the range from about 1.1 to about 1.6 (at about 550 nm). In other embodiments, the thickness 220 of the OCA layer 206 may be in the range from about 0.01 mm to about 0.1 mm. In other embodiments, the transmittance of the OCA layer 206 may be in the range from about 50% to about 90%, such as in the range from about 60% to about 85%, or in the range from about 60% to about 80%. In other embodiments, the refractive index of the OCA layer 206 may be in the range from about 1.2 to about 1.4.

[0346] In an embodiment, the thickness 222 of the glass layer 208 between the top surface 212 of the OCA layer 206 and the top surface 218 of the glass layer 208 may be in the range from about 0.05 mm to about 2 mm, such as in the range from about 0.1 mm to about 0.3 mm. It has been observed that by using a glass cover plate 208 including glass with reduced transmittance on a top-emitting display, such as the glass with reduced transmittance disclosed herein, the contrast ratio of the display can be improved. Thus, the transmittance of the glass layer 208 (i.e., the glass cover plate) (at a glass layer thickness of about 550 nm) may be in the range from about 40% to about 98%, such as in the range between about 40% and about 90%, in the range from about 50% to about 90%, in the range from about 50% to about 85%, or in the range from about 60% to about 80%. The refractive index of the glass layer 208 (at about 550 nm) may be in the range from about 1.4 to about 2.0, such as in the range from about 1.5 to about 1.7.

[0347] Figure 12 is a side view of an exemplary micro-LED 300. In a particular illustrative embodiment, the micro-LED 300 may be used for the micro-LEDs 204a, 204b, and / or 204c within each pixel 204, as referenced Figures 9 - 11Previously described and shown. The micro-LED 300 may include a contact pad 302 (e.g., a metal pad), a bottom passivation layer 304, an active layer 306 (e.g., a multi-quantum well (MQW) active layer), and a top passivation layer 308. The contact pad 302 is electrically coupled to the top surface 210 of the bottom plate 202. The bottom surface of the bottom passivation layer 304 contacts the contact pad 302. The top surface of the passivation layer 304 contacts the bottom surface of the active layer 306. The top surface of the active layer 306 contacts the bottom surface of the top passivation layer 308. Each contact pad 302 may have a height (thickness) 310 of about 1 micron and a width 312 of about 10 microns. The distance 314 between the contact pads 302 may be about 10 microns. The height (thickness) 316 of the bottom passivation layer 304 may be about 2.2 microns, the height (thickness) 318 of the active layer 306 may be about 0.6 micron, and the height 320 of the top passivation layer 308 may be about 2.2 microns, such that the total height 322 in the micro-LED 300 may be about 5 microns. In other embodiments, the micro-LED 300 may have other suitable dimensions.

[0348] Figure 13 Is a top view of an exemplary pixel 204 including micro-LEDs 204a, 204b, and 204c. Each of the micro-LEDs 204a, 204b, and 204c includes a length 332 of about 30 microns and a width 334 of about 20 microns. The distance 336 between the micro-LEDs within the pixel 204 may be about 25 microns. In other embodiments, the micro-LEDs 204a, 204b, and 204c and the pixel 204 may have other suitable dimensions.

[0349] It should be clear that the aspects described herein, although discussed with respect to tiled displays, may also be applicable to a single display panel. For example, using glass with reduced transmittance in a display device, such as as a glass cover plate to improve contrast, may be applicable to non-tiled display devices.

[0350] In an experiment, twelve exemplary display devices 104 were modeled to demonstrate the benefits of using glass with reduced transmittance as a cover plate. The modeled display devices included a bottom plate 202, which included a plurality of pixels 204. In this example, each pixel included three LEDs (e.g., micro-LEDs), each LED having a lateral dimension of 20 μm × 30 μm 334, 332 and a height of 5 μm relative to the front surface of the bottom plate substrate, and the spacing (distance 336) from the adjacent edge to the adjacent edge of adjacent LEDs was assumed to be 25 μm. The pixel pitch, i.e., the distance between two adjacent LEDs of two adjacent pixels, was assumed to be 200 μm. The display size was assumed to be 5 mm × 5 mm, and the reflectance of the front bottom plate substrate surface was assumed to be 5%. In addition, the display device included a protective glass plate 208 adhered to the bottom plate by an optically transparent adhesive layer 206, and the adhesive layer 206 encapsulated the micro-LEDs. Three groups of four display devices were modeled, each group including three different protective glass thicknesses, 0.25 mm, 0.50 mm, and 0.7 mm. The modeling parameters are shown in Table 6.

[0351] Table 6

[0352]

[0353]

[0354] The light emitted from the edge surface (at a 45-degree angle) of the twelve exemplary displays and the light emitted from the front (towards the observer) surface of the display at the protective glass surface were modeled. The modeling was performed with the help of Lighttools lighting software from Synopsys, Sunnyvale, California, USA. The luminance ratio LR was calculated, where the luminance ratio was the luminance value of the light 340 emitted from the edge of the display at a 45-degree angle and the luminance value of the light 342 emitted at an angle perpendicular to the front (front) surface of the display. Figure 14 A schematic diagram of the measurement is provided, while Figure 15Shows curves of the luminance ratio as a function of the transmissivity of the protective glass for protective glass thicknesses of 0.7 mm (square), 0.5 mm (circle), and 0.25 mm (triangle). The data shows that as the transmissivity of the protective glass decreases, for example, in the range from about 62% to about 92%, the luminance ratio also decreases from about 99% to about 38%, depending on the thickness, indicating that edge light leakage is reduced through the protective glass substrate with reduced transmissivity. For example, for a thickness of 0.7 mm, in the transmissivity range from about 92% to about 62%, the luminance ratio LR decreases from about 99% to about 65%. For a thickness of 0.5 mm, in the transmissivity range from about 92% to about 62%, the luminance ratio LR decreases from about 91% to about 49%. For a thickness of 0.25 mm, in the transmissivity range from about 92% to about 62%, the luminance ratio LR decreases from about 80% to about 38%. Assume that the bottom plate has a reflectance Rb of about 5%.

[0355] By quantifying the effect on the display washout, the improvement in the contrast of a display device using glass with reduced transmissivity, such as used as a cover substrate, can be understood. As used herein, washout refers to the degradation of the contrast and resolution of a display due to strong ambient light, such as sunlight. Accordingly, a measurement method for determining the washout effect (e.g., washout index) originating from a glass substrate is disclosed.

[0356] A method for determining the washout index (WI) of a glass substrate, hereinafter referred to as the WI measurement method, includes determining the modulation transfer function (MTF) of a display image generated by a display device when viewed through a target glass substrate under illumination conditions mimicking a desired use case, such as in direct sunlight. Then, the average value of the MTF within a predetermined spatial frequency range can be used to determine the washout index WI.

[0357] The MTF of an optical system is defined as the ratio of the output image modulation function (MFout(fn)) to the input image modulation function (MFin(fn)), written as:

[0358]

[0359] where,

[0360]

[0361] and

[0362]

[0363] and

[0364] where f n represents the image spatial frequency, I in (f n ) maxand I in (f n ) min represent the maximum and minimum intensities of the input modulated image at the spatial frequency f n respectively, and I out (f n ) max and I out (f n ) min represent the maximum and minimum intensities of the output modulated image at the spatial frequency f n respectively.

[0365] The washout index WI of the glass substrate to be measured (test sample) can be expressed by the following equation,

[0366]

[0367] where, MF in is the measured modulation function of the MTF target displayed by the display without the test sample in a dark room, and MF out is the measured modulation function of the MTF target displayed by the display with the test sample under ambient light conditions.

[0368] Figure 16 is a schematic diagram of the measurement setup used to evaluate the washout effect produced by the glass substrate in an exemplary use case, such as simulating a driver viewing a display in a car. In this use case, the driver is looking at the information center display and sunlight is shining directly in through the driver's front door window. As Figure 16 shown, the viewing angle of the driver represented by the camera 350 (e.g., a CCD camera) with respect to the display normal 352 corresponding to the camera optical axis is 0 degrees, and the incident angle Ia of the sunlight 354 with respect to the display normal is 20 degrees. The measurement system includes four components: in this case, a collimated light source 356 representing sunlight, a display device 358, the test sample glass substrate 360, and the camera 350. A mini Apple iPad4 (model A1538) with a resolution of 326 pixels per inch (ppi) is used to display the MTF target pattern (1951 USAF resolution test chart, Figure 17is shown in part). A collimated LED light source 356 (e.g., a projection light source, MIGHTEX, P / N: LCS-6500-65-22 high-power LED collimator light source, glacier white 6500K, 65 watts, 22mm aperture) simulates sunlight illumination and is placed 50 cm away from the sample under test at an angle of 20 degrees with respect to the surface normal 352 (an axis orthogonal to the surface) of the sample under test. The glass substrate sample 360 under test is placed near the display device 358, e.g., against the front (facing the observer) surface of the display. If the surface of the sample under test 360 includes an anti-glare or anti-reflection treatment, or both, the treated surface faces the camera. The camera 350 includes a high-resolution CCD camera (Pixelink 3.1MP PL-B776) with a 50mm focal length lens (HP series fixed focal length lens, stock number 86-574), and captures display images of the MTF target pattern before and after the sample under test is positioned 50 cm in front of the display device 358 on a line orthogonal to the front surface of the sample under test. Before positioning the sample under test in front of the display device (between the display device 358 and the camera 350), the camera 350 captures an MTF image under darkroom conditions and without collimated light. After positioning the sample under test in front of the display device 358 (e.g., against the protective glass of the display device), the camera 350 captures an MTF image under room light with the collimated light source 356 turned on. The illuminance of the room at the display device with ceiling lights is 132 lux, and the illuminance of the display surface under the illumination of the collimated light source is 45000 lux. Five spatial frequencies are selected from the MTF images for WI calculation: f 1 = 1.67 cycles / mm, f 2 = 4.11 cycles / mm, f 3 = 7.33 cycles / mm, f 4 = 10.38 cycles / mm, and f 5 = 13.08 cycles / mm, where f 5 = 13.08 cycles / mm is equal to or approximately equal to the resolution of the display device.

[0369] For example, the washout indices of four samples were tested, and the data are shown in Table 7: Corning with an anti-glare surface Gorilla Glass samples (GG), Corning Incorporated Eagle XG samples (EXG), glasses described herein including transition metal doping to obtain 85% transmittance (N85), and glasses described herein including transition metal doping to obtain 70% transmittance (N70). Two samples, the tested sample with 70% transmittance (N70) and the tested sample with 85% transmittance (N85), have lower transmittance than the other two samples (GG and EXG). Among the four samples, only the GG sample was treated with anti-glare (on the front).

[0370] Figure 18 A curve showing the measured washout index (WI) of a display covered by the tested samples as a function of the transmittance of the tested samples is presented. As is clearly shown, the washout index decreases as the transmittance of the tested glass samples decreases, indicating that when used in a display device (e.g., as a protective glass substrate), a protective glass substrate with a reduced transmittance can reduce display washout.

[0371] Figure 19 The measured washout index WI of a display device with four different samples is presented. Compared with the sample with a smooth front surface (EXG), adding an anti-glare (AG) treatment (GG with AG) on the front surface of the display protective glass worsens the washout effect due to the scattering of the anti-glare surface. However, reducing the transmittance of a protective glass substrate with anti-glare, anti-reflection, or both anti-glare and anti-reflection can help suppress the washout effect of a display with such surface treatments.

[0372] Table 7

[0373]

[0374] Examples

[0375] Example 1

[0376] Polycrystalline silicon ring field effect transistors (FETs) were fabricated on doped Ni and Co Lotus glass wafers and undoped Ni and Co Lotus samples (as a reference). Three wafers were processed under each condition. Figure 20 The polycrystalline silicon ring FET manufacturing process 400 is shown in. The Lotus 2 glass wafer 402 was coated with a 100 nm SiO Figure 20(b)). The a-Si film is dehydrogenated under vacuum at 450 °C for 1 hour and then annealed at 630 °C for 12 hours to produce crystallization and the resulting polycrystalline silicon layer 408 on top of the SiO 2 layer 404 ( Figure 20 (c)). A 250-nanometer aluminum (Al) layer is sputter-deposited and then patterned by photolithography to produce the source electrode 410 and the drain electrode 412 ( Figure 20 (d)). A 100-nanometer SiO 2 layer 414 is deposited as the gate insulator, and a 250-nanometer Al layer is sputter-deposited on top of it. The top Al layer is patterned to form the top gate electrode 416, and the source and drain contacts are patterned. Finally, the device is annealed at 450 °C for 1 hour to form the FET 418.

[0377] Figure 21 The annular FET layout is shown from the top. The diameter of the FET device is 140 μm and the thickness is 700 μm. The FET device is measured by scanning the gate voltage from 5 volts to -30 volts while the drain is applied with -30 volts, -20 volts, -10 volts, -5 volts, and -1 volt respectively and the source is grounded. Fifty-seven FETs are measured on each wafer. Figure 22 shows the typical transfer curve (drain current as a function of gate voltage) of the annular FET.

[0378] Transfer curves of the annular FET with different drain voltages are obtained on doped Ni and Co Lotus glass and undoped (normal) glass. Under the same measurement conditions, all wafers exhibit the same performance. The cut-off current (Min(Id)) of the FET device is extracted from the transfer curves and plotted with different drain voltages (Vd), and is shown in Figure 23 , which further confirms the observations from the transfer curves.

[0379] Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is used to measure the depth profiles of Ni and Co + ion concentrations on Lotus + glass doped with Ni and Co (curve 460) and undoped with Ni and Co (curve 462) after the fabrication of the annular FET. To reduce the complexity of the thin film stack, the region without the Al electrode is measured by TOF-SIMS. Figure 24 shows the TOF-SIMS results. Co ions exhibit good stability in the glass, and Ni ions diffuse out of the glass after the high-temperature deposition process but concentrate in the polycrystalline silicon layer.

[0380] In summary, the TFT is deposited on a glass substrate including nickel and cobalt. Measurements performed on the TFT found no effect on the performance parameters of the TFT, indicating that using small amounts of Co and Ni to address light leakage is unlikely to affect the performance of devices using such doped glass.

[0381] Example 2

[0382] To model the contrast of a packaged top-emitting micro-LED display, such as the display depicted in Figures 7 - 11 , with specific reference to Figure 9 , several micro-LEDs in the central region of the display are turned on while the remaining micro-LEDs of the display are turned off. Figure 25 A top view of the micro-LED display to be modeled is shown, and the central region pixels from (1,1) to (5,5) are schematically depicted. As shown in Figure 25 , for the 5×5 pixels from (1,1) to (5,5) in the central region of the display, all other micro-LEDs in the 5×5 array are turned on when the micro-LEDs in four pixels (2,2), (2,4), (4,2), and (4,4) are turned off. Here, the definition of the display contrast is defined as display contrast (%) = ((average illuminance of active pixels) / (average illuminance of dark pixels)) × 100.

[0383] In the following modeling, the dark pixels used to calculate the display contrast include the pixels (2,2), (2,4), (4,2), and (4,4), and all other active pixels in the central region are used to calculate the active display contrast.

[0384] Table 8 shows the encapsulation geometric parameters, glass cover plate, and OCA material parameters. Two cases are studied. One case (Case 1) includes a device with an OCA layer having a refractive index of 1.49, and the other case (Case 2) includes a device with an OCA layer having a refractive index of 1.40.

[0385] Case 1, in which the OCA layer with a refractive index of 1.49 is modeled.

[0386] Table 8

[0387]

[0388] Figure 26 Shows the normalized average illuminance of active and dark pixels as a function of the glass cover plate transmittance. Figure 27 Shows the display contrast as a function of the glass cover plate transmittance. Figure 28Show the contrast improvement of a display as a function of the transmittance of the glass cover plate. The improvement of the display contrast by reducing the transmittance of the glass cover plate is defined by Contrast improvement (times) = (Display contrast w / Protective glass transmittance Tg) / (Display contrast w / Protective glass transmittance Tg = 91.7).

[0389] As Figure 26 shown, the illuminance of both the active pixels and the dark pixels decreases as the optical transmittance of the glass cover plate decreases. However, as the transmittance of the glass cover plate decreases, the rate of decrease in the illuminance of the active pixels is much slower than that of the dark pixels. The illuminance of the active pixels decreases linearly as the transmittance of the glass cover plate decreases, and the illuminance of the dark pixels decreases approximately exponentially as the transmittance of the glass cover plate decreases. This results in an improvement in the display contrast by reducing the transmittance of the glass cover plate. As Figure 27 shown, the contrast, expressed as a percentage, is plotted as a function of the transmittance of the protective glass plate, expressed as a percentage. The contrast of the display increases as the transmittance of the glass cover plate decreases, although this improvement begins to saturate after the transmittance of the glass cover plate drops to less than about 70%. As Figure 28 shown, the improvement in contrast increases as the transmittance of the glass cover plate decreases. Compared to a display using a glass cover plate with a transmittance of 91.7%, the display contrast can be increased by more than 25 times when the transmittance of the glass cover plate is less than about 80%.

[0390] Second, Case 2, in which the OCA with a refractive index of 1.40 is modeled. Figure 29 Show the normalized average illuminance of the active and dark pixels as a function of the transmittance of the glass cover plate. Figure 30 Show the display contrast as a function of the transmittance of the glass cover plate. Figure 31 Show the contrast improvement of the display as a function of the transmittance of the glass cover plate. Similar to Case 1, the data indicate that the contrast improvement of the display can be achieved by reducing the transmittance of the glass cover plate. Therefore, the analysis shows that introducing appropriate (e.g., increased) optical absorption in the glass cover plate of a packaged top-emitting micro-LED display can not only significantly reduce the edge light leakage of the display but also significantly improve the contrast of the display.

[0391] Example 4

[0392] In another experiment, the diffusion of Ni and Co in a glass substrate doped with transition metals was tested in the presence of a barrier layer to determine whether the glass described herein, which is used as a bottom substrate and / or a substrate (e.g., to mitigate edge light leakage), poses a risk of contaminating the TFTs deposited on the bottom substrate. First, an approximately 100 nm thick silicon nitride (commonly denoted as SiNx, where SiNx represents a nitride of silicon, e.g., Si 3 N 4 ) layer was deposited on a 5 cm × 5 cm, 0.7 mm thick glass substrate in a furnace at 400 °C by plasma-enhanced chemical vapor deposition (PECVD). Subsequently, an approximately 100 nm thick silicon dioxide (SiO 2 ) layer was deposited, and finally, an amorphous silicon layer (a-Si) was deposited on the silicon dioxide layer to represent the TFT. The glass substrate was NXT glass doped with sufficient amounts of Ni and Co to obtain an optical transmittance of 70%. After adding these layers, the glass substrate was cooled to room temperature at the furnace rate, and then the glass substrate was heated to a temperature of 620 °C at a rate of approximately 5 °C / second in nitrogen (N N 2 ) for 30 minutes, and then cooled from 620 °C to approximately 350 °C at a rate of approximately 5 °C / second, after which the cooling rate was reduced. After the glass was cooled to room temperature, the samples were measured by TOF-SIMS, where the measurements were made at different depths of the layered glass substrate. The data are presented in Figure 32 , showing the normalized intensity as a function of the depth into the coated surface of the glass substrate.

[0393] The experiment was also conducted on a second glass substrate, where a first layer of silicon dioxide was deposited on the glass substrate with a thickness of approximately 200 nm, and then an a-Si layer with a thickness of approximately 60 nm was deposited on the silicon dioxide layer. The data for this glass substrate are presented in Figure 33 , again showing the normalized intensity as a function of the depth into the coated surface of the glass substrate.

[0394] Figure 32 and Figure 33 show the cobalt (Co, circular data points) markers, which essentially stop at the glass-SiNx interface. Nickel (Ni, square data points) is more mobile in the glass, resulting in a greater intensity at the glass-SiNx interface, but again does not further diffuse into the SiNx boundary layer. Figure 32 shows the presence of nitrogen (N, asterisk data points) as a result of the silicon nitride. Silicon (Si) is represented by triangular data points. Now referring to Figure 33 , although the second experiment used a SiO 2 barrier layer and no SiNx layer, and the simulated TFT was deposited on it, the results are almost the same as Figure 32The results are the same as shown. That is, Figure 32 and Figure 33 In the view of SiNx and / or SiO 2 Both are shown to be effective barrier layers to prevent contamination of TFTs deposited on Ni and / or Co doped glass when located between the TFT (or other electronic components, such as thin film components) and the doped glass.

[0395] Example 5

[0396] will include doping with sufficient amounts of Ni and Co to obtain a transmittance of 70% The glass substrate of the NXT glass is supported on a silicon wafer and is spaced 700 mm from the silicon wafer by silicon spacers. The purpose of the experiment is to determine the extent to which the Co or Ni doped glass releases (e.g., by evaporation) the Co or Ni to the extent that it contaminates the interior of a furnace (e.g., a furnace for TFT deposition) or other components in the furnace (e.g., display devices\TFTs, etc.). In a nitrogen atmosphere (N 2 ), the sample was heated to 620°C in a furnace and the furnace was maintained at 620°C for 30 minutes at a rate of about 5°C / second. The glass substrate was then cooled to room temperature. Once cooled, the doped glass was removed and the silicon wafer surface facing the doped glass substrate was measured by TOF-SIMS. Figure 34 The data are presented in Figure 1. The circular data points represent Co, the square data points represent Ni, and the triangular data points represent Si. Nitrogen is represented by the asterisk data points. It is believed that the presence of nitrogen is due to contamination from the furnace and / or nitrogen from the heating environment. However, the data shows that outside the barrier layer, there is virtually no intensity signal for Co and / or Ni, indicating that under typical TFT deposition conditions, when used in the presence of a boundary layer, the glasses doped with Co and / or Ni described herein do not pose a contamination risk.

[0397] The glasses and glass articles described herein can be strengthened glasses.As used herein, the term "strengthened" can refer to a material that has been chemically strengthened, for example, by ion exchange of larger ions with smaller ions in a substrate surface, as discussed below.

[0398] Glass can be chemically strengthened by exposing the glass (e.g., a glass substrate) to one or more ion exchange media (e.g., a molten salt solution). The exchange medium can include, for example, a molten nitrate (e.g., KNO 3 、NaNO 3 or combinations thereof), although other sodium and / or potassium salts, such as sodium or potassium nitrites, phosphates, or sulfates, may be used in the ion exchange medium. In various aspects, the ion exchange medium may include a lithium salt, such as LiNO 3。The ion exchange medium may additionally include additives commonly included when ion exchanging glass, such as silicic acid. In various aspects, the ion exchange medium may include a mixture of sodium and potassium (e.g., including NaNO 3 and KNO 3 both). In various aspects, the ion exchange medium may include any combination of NaNO 3 and KNO 3 , such as a molten salt bath containing 80 wt% NaNO 3 and 20 wt% KNO 3 .

[0399] However, other strengthening methods, such as thermal tempering, or taking advantage of the mismatch in the coefficient of thermal expansion between parts of the substrate to create regions of compressive stress and central tension, may also be used to form a strengthened substrate.

[0400] It will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the spirit and scope of the disclosure. Since the skilled person can conceive of modifications, combinations, sub - combinations and variations of the disclosed embodiments, the present disclosure should be construed to cover all such modifications within the scope of the appended claims and their equivalents.

Claims

1. A glass product, comprising: A glass substrate comprising an average optical transmittance equal to or less than about 91% in a wavelength range from 450 nm to 650 nm, and a washout index WI equal to or less than 0.165 when measured by a WI measurement method.

2. The glass article of claim 1, wherein the average optical transmittance is in the range of from 50% to 90%.

3. The glass article of claim 1, wherein the glass of the glass substrate does not contain alkali.

4. The glass article of claim 3, wherein the glass has an annealing point greater than 700°C.

5. The glass article of claim 3, wherein the glass has a liquidus temperature greater than 1000°C.

6. The glass article of claim 5, wherein the liquidus temperature is in the range from 1000°C to 1300°C.

7. The glass article according to any one of claims 1 to 6, wherein the thermal expansion coefficient of the glass substrate is in the range of 29×10 -7 Up to 40×10 -7 in the range.

8. The glass article of claim 3, wherein the glass has a density equal to or less than 2.65 g / cc 3 .

9. The glass article of claim 1, wherein the glass article comprises a display device.

10. The glass article of claim 9, wherein the glass substrate comprises a cover substrate of a display panel of the display device.

11. The glass article according to claim 9, wherein a brightness ratio of the display device is equal to or less than 91%.

12. The glass article of claim 1, wherein the composition of the glass of the glass substrate comprises, in mole percentages based on oxides: SiO2 61–74; Al2O3 9–14; B2O3 0–12; MgO 0–9; CaO 3.5–12; SrO 0–5; BaO 0–5; SnO2 0–0.15; NiO 0.025–0.13; Co3O4 0.005–0.04, and Among them, (MgO+CaO+SrO+BaO) / Al2O3 is equal to or greater than 1.

13. The glass article of claim 12, wherein the glass comprises: NiO 0.055–0.065; and Co3O4 0.011–0.

013.

14. The glass article of claim 12, wherein the glass comprises: NiO 0.077–0.128; and Co3O4 0.025–0.

037.

15. A display device, comprising: a display panel comprising a plurality of light emitters disposed on a base substrate, and a glass cover substrate disposed on the base substrate and attached thereto by an adhesive layer, the glass cover substrate comprising an average transmittance equal to or less than 91% within a wavelength range from 450 nm to 650 nm; and The brightness ratio of the display device is equal to or less than about 91%. 16 . The display device of claim 15 , wherein a washout index WI of the glass cover substrate is equal to or less than 0.165 when measured by a WI measurement method.

17. The display device of claim 15, wherein the glass cover substrate comprises glass, the glass comprising, in mole percentage on an oxide basis: SiO2 61–74; Al2O3 9–14; B2O3 0–12; MgO 0–9; CaO 3.5–12; SrO 0–5; BaO 0–5; SnO2 0–0.15; NiO 0.025–0.13; Co3O4 0.005–0.04, and Among them, (MgO+CaO+SrO+BaO) / Al2O3 is equal to or greater than 1.

18. The display device of claim 17, wherein the glass comprises: NiO 0.055–0.065; and Co3O4 0.011–0.

013.

19. The display device of claim 17, wherein the glass comprises: NiO 0.077–0.128; and Co3O4 0.025–0.

037.

20. The display device of claim 17, wherein the glass has an annealing point greater than 700°C.

21. The display device of claim 17, wherein a liquidus temperature of the glass is in a range from 1000°C to 1300°C.

22. The glass article of claim 17, wherein the coefficient of thermal expansion of the glass is in the range of 29×10 -7 Up to 40×10 -7 in the range.

23. The glass article of claim 17, wherein the glass has a density equal to or less than 2.65 g / cc 3 .

24. The glass article of claim 15, wherein the average transmittance is equal to or less than 90% in the wavelength range from 450 nm to 650 nm.

25. The glass article of claim 15, wherein the average transmittance is equal to or less than 85% in the wavelength range from 450 nm to 650 nm.

26. The glass article of claim 15, wherein the average transmittance is equal to or less than 80% in the wavelength range from 450 nm to 650 nm.

27. The glass article of claim 15, wherein within the wavelength range of from 450 nm to 650 nm, the average transmittance ranges from 50% to 91%.

Images