Reduced light transmittance glasses for emissive displays.

Abstract

Disclosed herein are glasses that can be used to manufacture substrates for flat panel display devices. The glasses may be substantially alkali-free. The glasses may be doped with one or more transition metals (e.g., Ni, Co) to exhibit reduced light transmittance to suppress light leakage from the display device and / or to 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 bottom plate having multiple display substrates disposed thereon, a display substrate (e.g., a backplane) having multiple light emitters disposed thereon, a glass cover plate, or a combination thereof.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority under 35 U.S.C. § 119 to U.S. Provisional Application No. 63 / 367225, filed June 29, 2022, U.S. Provisional Application No. 63 / 432889, filed December 15, 2022, and U.S. Provisional Application No. 63 / 507744, filed June 13, 2023, the contents of which are relied upon and incorporated by reference herein in their entireties. FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate to light-emitting displays, and more particularly, to glass substrates suitable for light-emitting display devices and exhibiting reduced transmittance. [Background technology]

[0002] Emissive displays, such as microLED (μLED) displays and organic light-emitting diode (OLED) displays, are highly desirable, but mass production of these displays suffers from low production yields and high costs, and the emergence of high-resolution displays poses technical challenges. One challenge concerns the fabrication of large-area light-emitting displays. A widely accepted, cost-effective method for creating large-area light-emitting displays is to arrange multiple small-format displays (tiles) to form a large-area display. However, such designs can result in light leakage at the edges of individual tiles. This light leakage can be visible to an observer as a bright line at the seams between tiles. Several methods exist to reduce the visibility of the seams; one is edge coating. Another is lamination of low-transmittance films. In the case of edge coating, the accuracy and reliability of the coating are challenges. In the case of lamination of low-transmittance films, the main issue is reliability, including both mechanical and environmental durability.

[0003] Another problem that can occur in emissive displays is a reduction in contrast ratio. Due to the optical confinement of the light guide formed by the encapsulation layers of an 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 can leak through the light guide to an adjacent pixel. This can result in a reduction in the contrast of the display and can cause a "halo" effect. Summary of the Invention

[0004] In a first aspect, In mole percent on an oxide basis, SiO261~74 and; Al2O39~14 and; B2O30~12 and; MgO 0-9 and; CaO 3.5-12 and; SrO 0-5 and; BaO 0-5 and; SnO20~0.15 and; NiO 0.025~0.13 and; Co3O40.005~0.04 and 1. A glass article comprising a glass having a composition comprising: (MgO+CaO+SrO+BaO) / Al2O3 is about 1 or more, Disclosed is a glass article, wherein the average light transmittance of the glass article over the wavelength range of 450 nm to 650 nm at a thickness of 0.7 mm is less than about 90%. The glass may be alkali-free. In a second embodiment, the average light transmittance of the glass article of the first embodiment can be in the range of about 60% to about 82%. The light transmittance of the glass article over the wavelength range of 450 nm to 650 nm at a thickness of 0.7 mm can be no more than + / - 5% of the average light transmittance. In a third embodiment, the glass of the first embodiment or the second embodiment can have an anneal point greater than about 700°C. In a fourth embodiment, the annealing point of the third embodiment can be in the range of about 710°C to about 810°C. In the fifth aspect, the liquidus temperature of the glass of any one of the first to fourth aspects can be greater than about 1000°C.

[0005] In a sixth embodiment, the liquidus temperature of the fifth embodiment can be in the range of about 1000°C to about 1300°C. In a seventh aspect, the thermal expansion coefficient of the glass article according to any one of the first to sixth aspects is about 29 × 10 over a temperature range of 0 ° C to 300 ° C. -7 ~About 40×10 -7 The range can be: In an eighth aspect, the density of the glass article of any one of the first to seventh aspects is about 2.65 g / cc 3 It can be: In a ninth aspect, the glass of any one of the first to eighth aspects can contain B2O3 in an amount ranging from about 0.2 mol % to about 12 mol %. In a tenth aspect, the glass of any one of the first to ninth aspects can contain MgO in an amount ranging from about 0.9 mol % to about 8 mol %.

[0006] In an eleventh aspect, the glass of the first aspect comprises: SiO267~74 and; Al2O310~14 and; With B2O30~3; MgO 3-8 and; CaO 3.9-8 and; SrO 0-2 and; BaO 2-5 and may include:

[0007] In a twelfth aspect, the glass of the eleventh aspect comprises: SiO268~74 and; B2O3 0.2~2 and; MgO 3.5-8 and; CaO 3.9-6 and; SrO 1~1.6 and; BaO 3-5 and may include: In a thirteenth embodiment, the anneal point of the twelfth embodiment can be greater than about 800°C. In a fourteenth aspect, the thermal expansion coefficient of the glass article of any one of the twelfth to thirteenth aspects is about 34 × 10 over a temperature range of 0 ° C to 300 ° C. -7 ~About 40×10 -7 The range can be: In the fifteenth aspect, the liquidus temperature of the glass of any one of the twelfth to fourteenth aspects can be greater than about 1100°C.

[0008] In a sixteenth aspect, the glass of the first aspect comprises: SiO264~71 and; Al2O39~12 and; B2O37~12 and; MgO 0.9~3 and; CaO 6-12 and; SrO 0-2 and; BaO 0-1 and may include:

[0009] In a seventeenth aspect, the glass of the sixteenth aspect comprises: SiO266~71 and; MgO 0.9~2 and; CaO 7-11.5 and; SrO 0.5-1.5 and; BaO 0~0.1 and may include: In an eighteenth aspect, the glass of the first aspect comprises: SiO261~69 and; Al2O311~14 and; B2O35~9 and; MgO 2-9 and; CaO 3-9 and; SrO 1-5 and may include:

[0010] In a nineteenth aspect, the glass of the eighteenth aspect comprises: SiO264~69 and; B2O36~9 and; MgO 3-6 and; CaO 5-7 and; SrO 3-5 and may include: In a twentieth aspect, the glass of the first aspect comprises: SiO266~71 and; Al2O311~14 and; With B2O33~6; MgO 3-6 and; CaO 4-7 and; SrO 1-5 and; BaO 0-2 and may include:

[0011] In a twenty-first embodiment, the thermal expansion coefficient of the glass article of the twentieth embodiment is about 33×10 over a temperature range of 0°C to 300°C. -7 ~About 40×10 -7 The range can be: In the twenty-second embodiment, the liquidus temperature of the glass of any one of the twentieth to twenty-first embodiments can be greater than about 1100°C. In a twenty-third aspect, the glass of the twentieth aspect comprises: SiO266~69 and; Al2O312~14 and; With B2O34~5; MgO 4-6 and; CaO 5-7 and; SrO 1-4 and may include:

[0012] In a 24th aspect, the glass of any one of the 1st aspect to the 23rd aspect is NiO 0.055~0.065; Co3O4 0.011~0.013 and may include: In a 25th aspect, the glass of any one of the 1st aspect to the 23rd aspect is NiO 0.077~0.128; Co3O4 0.025~0.037 and may include: In a twenty-sixth aspect, a display device is disclosed comprising a plurality of display substrates arranged on a base plate comprising the glass of any one of the first to twenty-seventh aspects, each display substrate comprising a plurality of light emitters disposed thereon and configured to direct light through the base plate.

[0013] In a twenty-seventh embodiment, each display substrate can include a barrier layer between the glass and the plurality of light emitters, the barrier layer including at least one of silica or silicon nitride deposited on the display substrate. In a 28th aspect, a display device is disclosed, comprising: a display substrate having a plurality of light emitters disposed thereon; an optically transparent adhesive layer disposed over the plurality of light emitters on the display substrate; and a glass cover plate disposed over the OCA layer and comprising the glass described in any one of the 1st to 27th aspects. In a twenty-ninth embodiment, the display substrate may comprise the glass according to any one of the first to twenty-seventh embodiments.

[0014] In a thirtieth embodiment, the display substrate of the twenty-ninth embodiment can include a barrier layer comprising at least one of silica or silicon nitride deposited on the display substrate between the glass and the plurality of light emitters. In a thirty-first aspect, the display device of the thirtieth aspect may include a top-emission display device, wherein the plurality of light emitters are configured to direct light through a glass cover plate. Further embodiments of the present disclosure are directed to objects comprising glass produced by a downdraw sheet manufacturing process. Further embodiments are directed to glass produced by a fusion process or variations thereof. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments described below. [Brief explanation of the drawings]

[0015] [Figure 1]FIG. 1 is a top view of an exemplary bottom-emission display device including multiple display tiles arranged in rows and columns. [Figure 2] 2 is a cross-sectional view of a portion of the display device of FIG. 1. [Figure 3] 3 is a close-up cross-sectional view of a portion of the display device of FIG. 2. [Figure 4] FIG. 1 is a schematic diagram of a compact used to make precision sheet in a fusion downdraw process. [Figure 5] FIG. 5 is a cross-sectional view of the molded body of FIG. [Figure 6] 1 is a plot of the percent transmittance of representative glass compositions from Table 1 as measured with an optical power meter. [Figure 7] FIG. 2 is another top view of a top-emitting tiled display including multiple display tiles arranged in rows and columns. [Figure 8] FIG. 8 is a side cross-sectional view of the display of FIG. 7. [Figure 9] 8 is a top view of an individual display tile of FIG. 7 showing individual light emitters arranged on the display tile. [Figure 10] 8 is a cross-sectional view of a portion of the display of FIG. 7 illustrating some ways in which light can leak from the edges of individual tiles of the display. [Figure 11] 8 is a cross-sectional view of a portion of the display of FIG. 7, illustrating some additional ways in which light can leak out the edges of individual tiles of the display. [Figure 12] 10 is a side cross-sectional view of the light emitter of the display tile of FIG. 9. [Figure 13] 10 is a top view of some of the light emitters of the display tile of FIG. 9, showing dimensional parameters. [Figure 14] 1A-1D are a series of schematic diagrams for the fabrication of the ring FET device subjected to the experiments described herein. [Figure 15] FIG. 15 is a top view of the ring FET device shown in FIG. 14. [Figure 16]16 is a plot of a typical transfer curve (drain current as a function of gate voltage) for the ring FET of FIGS. 14-15. [Figure 17] 1 is a chart showing the off-current (min(Id)) of a FET device extracted from a transfer curve and plotted at different drain voltages (Vd). [Figure 18] 1 is a plot of time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurements used to determine the depth profile of Ni+ and Co+ ion concentrations on Lotus NXT® glass with and without Ni and CO doping after ring-FET fabrication. [Figure 19] 1 is a top view of the central portion of a top-emission display device subjected to experiments as described herein, showing a comparison of the "on" and "off" states of the emitters. [Figure 20] 20 is a plot showing modeled normalized average illuminance of active and dark pixels as a function of cover glass transmittance for the display of FIG. 19, where the refractive index of the OCA layer of the display was 1.49. [Figure 21] 1 is a plot showing the contrast of a display as a function of cover glass transmittance, where the refractive index of the OCA layer of the display was 1.49. [Figure 22] 20 is a plot showing the contrast improvement of the display of FIG. 19 as a function of cover glass transmittance, where the refractive index of the OCA layer of the display was 1.49. [Figure 23] 20 is a plot showing modeled normalized average illuminance of active and dark pixels as a function of cover glass transmittance for the display of FIG. 19, where the refractive index of the OCA layer of the display was 1.40. [Figure 24] 1 is a plot showing the contrast of a display as a function of cover glass transmittance, where the refractive index of the OCA layer of the display was 1.40. [Figure 25]20 is a plot showing the contrast improvement of the display of FIG. 19 as a function of cover glass transmittance, where the refractive index of the OCA layer of the display was 1.4. [Figure 26] 1 is a plot obtained from a TOF-SIMS analysis of a simulated TFT device disposed on a glass substrate comprising an 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 no diffusion of the transition metal into the simulated TFT device under typical deposition conditions. [Figure 27] FIG. 10 is another plot obtained from a TOF-SIMS analysis of a simulated TFT device disposed on a glass substrate comprising an 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 shows no diffusion of the transition metal into the simulated TFT device under typical deposition conditions. [Figure 28] 1 is a plot obtained from a TOF-SIMS analysis of a silicon wafer heated under typical TFT deposition conditions in close proximity to a glass substrate doped with a transition metal dopant (e.g., Ni, Co), showing the virtual lack of transition metal dopant evaporating from the glass substrate and subsequent contamination from the transition metal dopant. DETAILED DESCRIPTION OF THE INVENTION

[0016] Various disclosed embodiments may include specific features, elements, or steps that are described in connection with that particular embodiment. Particular features, elements, or steps that are described in connection with one particular embodiment can be interchanged or combined in alternative embodiments in various combinations or permutations not shown. As used herein, the terms "the," "a," or "an" mean "at least one" and should not be limited to "only one" unless expressly stated to the contrary. Ranges can be expressed herein as from "about" one particular value, and / or to "about" another particular value. When such a range is expressed, it includes, by way of example, from the one particular value and / or to the other particular value, e.g., within the error of measurement of such value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it is understood that the particular value forms another aspect. It is further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0017] As used herein, the terms "substantial," "substantially," and variations thereof are intended to indicate that a described characteristic is equal to or approximately equal to a value or description. Additionally, "substantially equivalent" is intended to indicate that two values are equal or approximately equal. In some embodiments, "substantially" or variations thereof (e.g., substantially equivalent) can refer to values that are within about 10% of each other, e.g., within about 5% of each other, within about 2% of each other, or within about 1% of each other. Unless otherwise expressly stated, it is not intended that any method described herein be construed as requiring that its steps be performed in a particular order. Thus, where a method claim does not actually recite the order in which the steps must be followed, or where the claim or description does not specifically state that the steps are limited to a particular order, no order is intended to be inferred.

[0018] Although various features, elements, or steps of embodiments may be disclosed using the transitional phrase "comprising," alternative embodiments are implied, including those that may be described using the transitional phrases "consisting of" or "consisting essentially of." Thus, for example, implied alternative embodiments of a device comprising A+B+C include embodiments in which the device consists of A+B+C and embodiments in which the device consists essentially of A+B+C. As used herein, the transitional phrases "comprising," "including," and "having" are to be considered open-ended unless expressly stated otherwise.

[0019] For brevity, any range of values disclosed herein, including a composition range or attribute (performance) range, or a series of ranges, may be supplemented with the phrase "including all ranges and subranges therebetween," which is to be interpreted as including any integer or fractional subranges, as if expressly set forth. Thus, for example, a range of 6 to 8 (units omitted) implicitly includes the subrange of 6.4 to 8, the subrange of 6 to 7.2, or the subrange of 6 to 7, etc. Furthermore, a series of ranges, such as "within the range of 6 to 11, or within the range of 6 to 8," implicitly includes the range of 7 to 10, or any subranges therebetween, such as 7.2 to 10.4, as if expressly set forth, unless the range exceeds the minimum or maximum endpoint of the explicitly set forth range or series of ranges. Thus, for example, "within the range of 6 to 11, or within the range of 6 to 8" has endpoints of 6 and 11.

[0020] Unless otherwise indicated, all components of the exemplary glass compositions disclosed herein are given in mole percent (mol%) on an oxide basis unless explicitly stated otherwise. As used herein, transmittance (or transmission) is defined as the ratio of incident light that strikes an object to the incident light that is transmitted through the object. The transmittance of an object can range from about 0 percent, where all incident light is prevented from passing through the object, to about 100 percent, where all incident light passes through the object. As used herein, the refractive index is defined as the ratio of the speed of light in a vacuum to the speed of light in a particular medium.

[0021] MicroLED is one of several next-generation display technologies that can offer high brightness, high contrast ratio, low power consumption, and high reliability, attributes that can meet or exceed the performance of competing technologies such as liquid crystal displays or organic light-emitting diode displays. Large-area displays are highly desirable for consumer and public information systems. However, high costs and low production yields present technical challenges for mass production of such large-area displays. This is particularly true for high-resolution micro-light-emitting diode (micro-LED) displays, at least due to the small size of the emitters. One solution for manufacturing large-area displays is to tile multiple individual small displays on a base plate, thereby forming a tiled display device in which the individual small displays constitute tiles. These tiles can be arranged, for example, in rows and / or columns, so that the size of the large-area display is scalable based on the number of individual small displays. The substrate underlying a micro-LED display can be glass or polymer, although glass can offer high-temperature compatibility and dimensional stability, making it a preferred substrate material.

[0022] A continuing problem in tiled applications is light leakage at the edges of the tiles. That is, light emitted from light emitters disposed on the tiles can be deflected through the edges of the tiles and then directed toward the viewer, for example, by reflection within the display from the backplane substrate on which the light emitters are mounted. Several methods have been proposed to mitigate light leakage, such as applying coatings to the edges of the tiles and / or laminating low-transmittance films to the backplane substrate. However, all have drawbacks, such as the ability to deposit the coating accurately, reliability, and durability, and the mechanical and environmental durability of the laminate film in particular. Another way to reduce light leakage through the gaps (seams) between tiles in the tiled display devices disclosed herein is to reduce the brightness of the leaked light. This can be achieved by using glass substrates that exhibit reduced transmittance. In other words, the light attenuation of the glass can be increased by intentionally doping the glass with a material that "colors" the glass.

[0023] Another problem suffered by emissive displays is a reduction in contrast ratio. Encapsulation layers (such as plates and optical adhesive layers) in emissive displays tend to form light guides that confine and direct light. Thus, light from one pixel emitter can leak through the light guide to an adjacent pixel, resulting in a reduction in the contrast of the display, which can appear as a "halo" effect to the viewer. This problem can also be solved by using glass substrates that exhibit reduced transmittance.

[0024] The glass compositions disclosed herein are generally alkali (alkali metal) free. However, glasses may contain some alkali metals as contaminants. For display applications, it is desirable to keep alkali metal levels below 0.1 mole percent (mol%) to avoid alkali ions diffusing from the glass into the silicon of thin film transistors (TFTs) and adversely affecting TFT performance. As used herein, an "alkali-free glass" is a glass with a total alkali metal concentration of 0.1 mole percent or less, where the total alkali metal concentration is the sum of the concentrations of Na2O, KO, and Li2O.

[0025] The glasses disclosed herein also relate to semiconductor assemblies comprising semiconductors disposed on glass substrates, the glass substrates comprising the alkali-free glasses of the present disclosure. Examples of semiconductors that can be used in such semiconductor assemblies 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 useful in electro-optical (EO) applications, two-photon mixing applications, nonlinear optical (NLO) applications, electroluminescent applications, and photovoltaic and sensor applications. Such semiconductor assemblies can comprise subassemblies of larger assemblies. For example, in embodiments, such semiconductor assemblies can comprise display assemblies, e.g., display tile assemblies, which themselves can form part of a larger display device, e.g., a flat panel display device, comprising a flat, transparent glass substrate carrying polycrystalline silicon thin-film transistors, the glass substrate comprising the alkali-free glasses of the present disclosure.

[0026] 1-3 are several diagrams of a representative display device 10 (e.g., a large-area display) including multiple display tiles 12 (small-format displays) arranged on a base plate 14. FIG. 1 is a top view of the display device 10 showing multiple display tiles arranged in rows and columns on the base plate 14. Referring to FIGS. 2-3, each display tile 12 includes a transparent substrate 16 having multiple light emitters 18 arranged thereon. The transparent substrate 16 may include, for example, glass or another non-conductive material, such as a polymer material. The light emitters 18 may be light-emitting diodes (LEDs). For example, the light emitters 18 may be micro-LEDs, each of which may include a light-emitting region having dimensions (length and / or width) ranging from about 1 micrometer (μm) to about 100 micrometers, although other dimensions, such as dimensions greater than 100 μm, are also contemplated. The light emitters 18 may be bottom-emitting emitters, with light emitted primarily from the bottom surface of the emitter through the substrate 16.

[0027] As best seen in FIG. 3 , which shows a close-up view of a portion of display device 10, base plate 14 includes a glass substrate including a first major surface 20 and a second major surface 22 opposite first major surface 20. Second major surface 22 may be parallel or substantially parallel to first major surface 20. Although two display tiles, a first display tile 12 a and a second display tile 12 b, are shown disposed on first major surface 20, more than two tiles may be disposed on first major surface 20. A gap (seam) G separates first display tile 12 a from second display tile 12 b. As further shown, light emitted from light emitters 18 is directed through base plate 14. A first portion 24 of the light passes directly through the base plate 14, while a second portion 26 of the light emitted by the light emitter 18 may be directed into the gap G, at least a portion of which may be directed outward from the display device 10 through the base plate 14 and be visible to a viewer 28 as a bright line. To mitigate the light observed in the gap, the base plate 14 may be formed of glass that exhibits a light attenuation (e.g., percent transmittance) that reduces the brightness of the light passing through the base plate.

[0028] As described herein, glasses suitable for use as the bottom plate 14 include alkali-free glasses with high annealing points (temperatures) and high Young's moduli, allowing the glass to have excellent dimensional stability (e.g., low compaction), thereby reducing variability during post-glass manufacturing processes. For example, in embodiments, substantially alkali-free glasses can have annealing points greater than about 700°C. In an embodiment, a representative glass can be fabricated into glass sheets by a fusion downdraw process. The fusion downdraw process can produce a clean, fire-polished glass surface that reduces surface-mediated distortion in high-resolution TFT backplanes and color filters. Figure 4 is a schematic diagram of a fusion forming body 30 in a non-limiting fusion downdraw process, and Figure 5 is a cross-sectional view of the forming body taken along line 5-5. Molten glass 32 is introduced through an inlet 34 and flows along the bottom of a cavity 36 formed by weirs 38 to the opposite end of the cavity 36. The molten glass overflows the weirs 38 on both sides of the forming body 30 (see Figure 5), and the two streams of molten glass meet or fuse at the bottom end (root) 42 of the forming body where the converging forming surfaces of the forming body meet, forming a ribbon of glass 44. Edge directors 46 at the opposing ends of the forming body 30 minimize lateral shrinkage of the glass ribbon 44 and create thicker strips, called beads, along the edges of the glass ribbon. The beads are caught and pulled down by counter-rotating pulling rolls (not shown), allowing for the formation of a high viscosity glass ribbon. By adjusting the speed at which the glass ribbon 44 is pulled from the former 30, a very wide range of glass ribbon thicknesses can be produced using the fusion downdraw process. Once formed, the glass ribbon 44 can be cut to the desired sheet size.

[0029] The fusion downdraw process, which can be used to form the glasses disclosed herein, is described in U.S. Patent Nos. 3,338,696 and 3,682,609. The fusion downdraw process can produce glass substrates that do not require polishing. Current glass substrate polishing can produce glass substrates with an average surface roughness (Ra) of greater than about 0.5 nanometers (nm), as measured by atomic force microscopy. Glass substrates produced by the fusion downdraw process can have an average surface roughness of less than about 0.5 nm, as measured by atomic force microscopy. Glass substrates produced by the fusion downdraw process can have an average surface roughness of less than about 0.5 nm, as measured by optical retardation, of about 150 psi (1.03×10 6Of course, the claims appended hereto should not be limited to fusion downdraw processes, and the embodiments described herein apply equally to other forming processes, such as, but not limited to, float forming processes, slot draw processes, rolling processes, and other sheet forming processes known to those skilled in the art.

[0030] Compared to these alternative methods of producing glass sheets, fusion downdraw processes, such as those described above, can produce very thin, very flat, very uniform, and clean-surfaced sheets of glass. While slot-draw processes also produce clean surfaces, the dimensional uniformity and surface quality of slot-draw glass are generally inferior to those of fusion-draw glass due to orifice shape changes over time, the accumulation of volatile debris at the orifice-glass interface, and the difficulty of creating orifices that provide truly flat glass. While the float process can produce very large, uniform sheets, contact with the float bath on one side and exposure to condensation products from the float bath on the other can significantly damage the surface. This means that float glass may require polishing for use in high-performance display applications.

[0031] The fusion downdraw process can involve rapid cooling of the glass from a high temperature, resulting in a high fictive temperature, T f The fictive temperature can be thought of as representing the difference between the structural state of the glass and the state it would assume if fully relaxed at the temperature of interest. The glass transition temperature, T g The glass is processed at a process temperature T p When reheated to T p <T g ≦T f can be affected by the viscosity of the glass. p is T f Since the temperature is lower than the T p The glass is deviated from equilibrium at Tp The relaxation rate is T p The effective viscosity varies inversely with the glass's effective viscosity at T, so a high viscosity results in a slow relaxation rate and a low viscosity results in a fast relaxation rate. The effective viscosity varies inversely with the glass's fictive temperature, so a low fictive temperature results in a high viscosity and a high fictive temperature results in a relatively low viscosity. Thus, T p The relaxation rate at T is directly proportional to the fictive temperature of the glass. p When reheated at 1000 K, the relaxation rate is relatively high.

[0032] T p One way to decrease the relaxation rate at T is to increase the viscosity of the glass at that temperature. As the temperature decreases below the anneal point, the viscosity of the melt increases. g At a fixed temperature below T, a glass with a high annealing point has a higher viscosity than a glass with a low annealing point. p The viscosity of the substrate glass at annealing point may increase. Generally, the compositional changes required to increase the annealing point also increase the viscosity at all other temperatures. In a non-limiting embodiment, the fictive temperature of the glass produced by the fusion process is about 10 11 ~about 10 12 Since it corresponds to a viscosity in poise, increasing the annealing point of a fusion-compatible glass generally also increases its fictive temperature. For a particular glass, regardless of the forming process, a high fictive temperature will increase the T g This results in a lower viscosity at temperatures below T. Thus, increasing the fictive temperature counteracts the viscosity increase obtained by increasing the anneal point. p To achieve a significant change in relaxation rate at 700°C, a relatively large change in anneal point is generally required. An exemplary glass embodiment disclosed herein can have an anneal point of about 700°C or higher. It is believed that such an anneal point can provide an acceptably low thermal relaxation rate during low temperature processing, such as a typical low temperature polysilicon rapid thermal anneal cycle.

[0033] In addition to its effect on the fictive temperature, increasing the anneal point also increases the temperature of the entire melting and forming system, particularly the temperature of the forming body. For example, Eagle XG® glass and Lotus™ glass (Corning Incorporated, Corning, NY) have anneal points that differ by about 50°C, and the temperatures delivered to the forming body can also differ by about 50°C. The zircon refractories that form the forming body can exhibit thermal creep when held above about 1310°C for extended periods of time, which can be accelerated by the mass of the forming body itself and the mass of glass on the forming body. A second embodiment of exemplary glasses disclosed herein can have a delivery temperature of about 1350°C or less, about 1345°C or less, about 1340°C or less, about 1335°C or less, about 1330°C or less, about 1325°C or less, about 1320°C or less, about 1315°C or less, or about 1310°C or less. Such delivery temperatures allow for extended production campaigns without having to change compacts or extending the time between compact changes.

[0034] In production tests of glasses with high annealing points and delivery temperatures below 1310°C, the glass can exhibit a greater tendency to devitrify at the root (bottom) of the forming body, particularly at the edge directors used to direct the glass across the forming body, compared to glasses with lower annealing points. Careful measurement of the temperature profile on the forming body shows that the temperature of the edge directors is much lower than expected compared to the center temperature along the bottom (root) of the forming body, likely due to radiative heat losses. The edge directors are maintained at a temperature lower than the center temperature of the forming body root, making the glass sufficiently viscous to separate from the root and maintaining a flat shape relative to the ribbon by placing the ribbon between the edge directors under tension. Because the edge directors are located at opposite ends of the forming body, heating the edge directors is difficult, and the temperature difference between the center of the root and the edge directors can vary by more than 50°C.

[0035] The increased tendency toward devitrification in the fusion downdraw process can be understood in terms of the radiative heat loss of the glass as a function of temperature. Because fusion is a substantially isothermal process, the glass enters the forming body at a particular viscosity and exits the root at a much higher viscosity, but the actual value of viscosity does not depend significantly on the identity of the glass or the temperature of the process. Thus, glasses with high anneal points generally require much higher forming body temperatures than glasses with low anneal points just to match the delivery and exit viscosities. Also, because radiative heat loss increases with temperature, and glasses with high anneal points are generally formed at higher temperatures than glasses with low anneal points, it is believed that the temperature difference between the center root and the edge director generally increases with the anneal point of the glass, which can be directly related to the tendency of the glass to form devitrification products on the forming body or edge director.

[0036] The liquidus temperature of a glass is defined as the highest temperature at which a crystalline phase appears if the glass is held at that temperature indefinitely. The liquidus viscosity is the viscosity of the glass at the liquidus temperature. To avoid devitrification on the forming body, it can be helpful for the liquidus viscosity to be high enough to ensure that there is no glass on the refractory or edge director material of the forming body at or near the liquidus temperature. In fact, few alkali-free glasses have liquidus viscosities in the desired order. Experience with display substrate glasses (e.g., Corning® Eagle XG® glass) indicates that edge directors can be continuously maintained at temperatures up to 60°C below the liquidus temperature of certain alkali-free glasses. While it was understood that glasses with high anneal points would require high forming temperatures, it was not anticipated that edge directors would be so low compared to the center root temperature. A useful metric for keeping track of this effect is the ratio of the delivery temperature of the molten glass to the forming body to the liquidus temperature T of the glass. liqIn the fusion downdraw process, it is generally desirable to deliver molten glass at about 35,000 poise. The temperature at which the glass reaches a viscosity of 35,000 poise is called T 35kP At a particular delivery temperature, T 35kP -T liq It can be useful to make T as large as possible, but for display substrates such as Corning® Eagle XG® glass, T 35kP -T liq If T is above about 80°C, extended production campaigns can be carried out. 35kP -T liq must also rise, so T 35kP When is around 1300℃, T 35kP -T liq Setting the temperature above about 100°C may help. 35kP -T liq The minimum useful value of varies approximately linearly with temperature from about 1200°C to about 1320°C and can be expressed according to equation (1). Minimum T 35kP -T liq =0.25T 35kP -225 (1) where all temperatures are in °C. Accordingly, one or more exemplary glasses disclosed herein may have a T 35kP -T liq >0.25T 35kP It can have a temperature of -225°C.

[0037] Furthermore, the forming process may require a glass with a high liquidus viscosity to avoid devitrification products at the interface with the glass and minimize visible devitrification products in the final glass. Thus, for a given glass compatible with fusion of a particular ribbon size and thickness, adjusting the process to produce wider or thicker ribbons generally results in lower temperatures at opposite ends of the forming body. Some embodiments have a higher liquidus viscosity, providing greater flexibility in manufacturing by the fusion process. Examination of the relationship between liquidus viscosity and subsequent devitrification tendency in the fusion process reveals that high delivery temperatures, such as those of representative glasses, generally require higher liquidus viscosities for long-term manufacturing than typical display substrate compositions with lower anneal points. This is believed to result from the accelerated rate of crystal growth as the temperature increases. Because fusion is essentially an isoviscous process, a more viscous glass at a fixed temperature can be fused at a higher temperature than a less viscous glass. While some degree of undercooling (cooling below the liquidus temperature) can be maintained for extended periods in low-temperature glasses, the rate of crystal growth increases with temperature, so a more viscous glass can grow an equally unacceptable amount of devitrification product in a shorter time than a less viscous glass. Depending on where it is formed, devitrification product can impair molding stability and introduce visible defects into the final glass.

[0038] To be formed by the fusion downdraw process, one or more embodiments of the glass compositions can have a liquidus viscosity of about 100,000 poise or greater, about 120,000 poise or greater, about 140,000 poise or greater, about 175,000 poise or greater, or about 200,000 poise or greater (including all ranges and subranges therebetween). Across the range of representative glasses, sufficiently low liquidus temperatures and sufficiently high viscosities can be obtained such that the liquidus viscosities of the glasses are significantly higher than other compositions. In addition to the glass formers (SiO, Al2O3, and B2O3), the glasses described herein can also include alkaline earth oxides. For example, one or more of at least three alkaline earth oxides, e.g., MgO, CaO, BaO, and an optional fourth, SrO, can be part of the glass composition. The alkaline earth oxides provide the glass with various properties important for melting, fining, forming, and final use. Therefore, to improve the performance of the glass in these respects, the (MgO + CaO + SrO + BaO) / Al2O3 ratio can be about 1 or greater. As this ratio increases, the viscosity tends to increase more strongly than the liquidus temperature, so that the T35kP -T liq It becomes increasingly difficult to obtain suitably high values of . Thus, in aspects, the (MgO + CaO + SrO + BaO) / Al2O3 ratio can be about 2 or less. In some embodiments, the (MgO + CaO + SrO + BaO) / Al2O3 ratio can be in the range of about 1 to about 1.8, in the range of about 1 to about 1.6, in the range of about 1 to about 1.4, in the range of about 1 to about 1.2, in the range of about 1 to about 1.16, or in the range of about 1.1 to about 1.6. For example, the (MgO + CaO + SrO + BaO) / Al2O3 ratio can be less than about 1.7, less than about 1.6, or less than about 1.5.

[0039] In certain embodiments, alkaline earth oxides can be treated as essentially a single component because their effects on viscoelastic properties, liquidus temperatures, and liquidus relations are qualitatively more similar to one another than the glass-forming oxides SiO, AlO, and BO. However, while the alkaline earth oxides CaO, SrO, and BaO can form feldspar minerals, particularly anorthite (CaAlSiO) and celsian (BaAlSiO), and their strontium-containing solid solutions, MgO does not participate in these crystals to any significant extent. Thus, when feldspar crystals are already in the liquid phase, the additional addition of MgO can help stabilize the liquid against crystallization and lower the liquidus temperature. At the same time, the viscosity curve typically becomes steeper and the melting temperature decreases, but with little or no effect on low-temperature viscosity. The addition of small amounts of MgO can provide benefits in terms of melting and forming, and therefore lower compression, by lowering the liquidus temperature, increasing the liquidus viscosity, and maintaining a high anneal point, thereby reducing the melting temperature.

[0040] T 35kP -T liqIn glasses with suitably high values of β, the ratio of MgO to other alkaline earth metals, MgO / (MgO + CaO + SrO + BaO), can fall within a relatively narrow range. As mentioned above, the addition of MgO can destabilize feldspar minerals, thereby stabilizing the liquid and lowering the liquidus temperature. However, once MgO reaches a certain level, mullite Al6SiO 13 The liquidus temperature can be stabilized, increasing the liquidus temperature and decreasing the liquidus viscosity. Furthermore, higher concentrations of MgO tend to decrease the viscosity of the liquid, so that even if the liquidus viscosity remains unchanged with the addition of MgO, it may ultimately decrease the liquidus viscosity. Thus, in embodiments, 0.10≦MgO / (MgO+CaO+SrO+BaO)≦0.40, or in other embodiments, 0.2≦MgO / (MgO+CaO+SrO+BaO)≦0.4. Within these ranges, MgO can be varied relative to the glass formers and other alkaline earth oxides to achieve other desired properties and consistently achieve the T. 35kP -T liq can be maximized.

[0041] The presence of calcium oxide in the glass composition is believed to produce a low liquidus temperature (high liquidus viscosity), a high anneal point and Young's modulus, and a CTE in the range most desirable for flat panel display applications. Calcium oxide also contributes favorably to chemical durability and is relatively inexpensive as a batch material compared to other alkaline earth oxides. However, at high concentrations, CaO increases density and CTE. Furthermore, at sufficiently low SiO2 concentrations, CaO can stabilize anorthite, thereby reducing liquidus viscosity. Both SrO and BaO can contribute to a low liquidus temperature (high liquidus viscosity). Therefore, the glasses described herein can include 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 anneal point. Balancing the relative proportions of SrO and BaO can provide the right combination of physical properties and liquidus viscosity to allow the glass to be formed in a downdraw process.

[0042] To summarize the effects and roles of the core components of the glass disclosed herein, SiO2 is the basic glass former. Al2O3 and B2O3 are also glass formers and can be selected in pairs, for example, by increasing B2O3 and correspondingly decreasing Al2O3 to lower density and CTE. On the other hand, increasing Al2O3 and correspondingly decreasing B2O3 can be used to increase the annealing point, Young's modulus, and durability, provided that the increase in Al2O3 does not significantly reduce the RO / Al2O3 ratio below about 1, where RO = (MgO + CaO + SrO + BaO). If the ratio becomes too low, meltability will be impaired, resulting in a too high melting temperature. For example, late melting of silica raw materials can make it difficult to remove gaseous inclusions from the glass. While B2O3 can be used to lower the melting temperature, high levels of B2O3 can impair the annealing point. Furthermore, when (MgO + CaO + SrO + BaO) / Al2O3 is less than about 1.05, mullite, an aluminosilicate crystal, may appear as a liquid phase. When mullite is present as a liquid phase, the composition sensitivity of the liquid phase increases significantly, and mullite devitrification products grow very rapidly and, once formed, can be very difficult to remove.

[0043] The concentrations of Al2O3 and B2O3 can be selected as a pair to increase the annealing point, increase Young's modulus, improve durability, lower density, and lower coefficient of thermal expansion (CTE) while maintaining the melting and forming properties of the glass. For example, increasing B2O3 with a concomitant decrease in Al2O3 can help to obtain a lower density and CTE, while increasing Al2O3 with a concomitant decrease in B2O3 can help to increase the annealing point, Young's modulus, and durability, as long as the increase in Al2O3 does not cause the (MgO+CaO+SrO+BaO) / Al2O3 ratio to fall significantly below about 1. In addition to considerations of meltability and annealing point, for display applications, the CTE of the glass can be selected to match that of silicon. To achieve such a CTE value, the RO content of the glasses disclosed herein can be controlled. For a given Al2O3 content, controlling the RO content corresponds to controlling the RO / Al2O3 ratio. In practice, an RO / Al2O3 ratio of less than about 1.6 produces glasses with suitable CTEs.

[0044] In addition to these considerations, one or more glasses disclosed herein are formable by downdraw processes, such as fusion processes, which means that the liquidus viscosity of the glass must be relatively high. Individual alkaline earth metals play an important role in this regard, as they can destabilize the crystalline phases that would otherwise form. BaO and SrO are particularly effective in controlling liquidus viscosity and can be included in representative glasses for at least this purpose. Various combinations of alkaline earth metals can be used to produce glasses with high liquidus viscosity, with the sum of the alkaline earth metals satisfying the R0 / Al2O3 ratio constraints necessary to achieve a low melting temperature, a high anneal point, and a suitable CTE.

[0045] In addition to the above components, the glass compositions described herein can include various other oxides to adjust various physical, melting, fining, and forming properties of the glass. Examples of such other oxides can include, but are not limited to, TiO, MnO, FeO, ZnO, NbO, MoO, TaO, WO, YO, LaO, and CeO. In embodiments, the amount of any of these oxides is 2.0 mole percent or less, and their total combined concentration is 5.0 mole percent or less. The glass compositions described herein may also include various contaminants, particularly Fe2O2 and ZrO2, associated with batch materials and / or introduced into the glass by the melting, fining, and / or forming equipment used to make the glass. The glass may contain SnO2 as a result of Joule melting using tin oxide electrodes and / or from batches of tin-containing materials, such as, for example, SnO2, SnO, SnCO3, SnCO2, etc.

[0046] To mitigate light leakage at the edges of the display tiles, the glasses disclosed herein can include transition metal components intentionally added to increase the transmission loss (reduce light transmittance) of the glass. For example, the glass can include nickel or cobalt in an amount sufficient to achieve reduced transmittance. In view of the above, various glass compositions are described in this disclosure. In these glass compositions, SiO2 functions as the primary glass former. In embodiments, the concentration of SiO2 is greater than about 60 mole percent, which can provide the glass with a density and chemical durability suitable for flat panel display glass substrates, as well as a liquidus temperature (liquidus viscosity) at which the glass can be formed by a downdraw process (e.g., a fusion downdraw process). Regarding the upper limit, the SiO2 concentration can generally be about 80 mole percent or less, allowing the batch materials to be melted using conventional high-volume melting techniques, such as Joule melting in a refractory melting vessel. As the concentration of SiO2 increases, the 200 poise temperature T 200P In various applications, the SiO2 concentration can be adjusted so that the glass composition has a melting temperature of about 1,750°C or less.

[0047] Thus, one or more embodiments of the present disclosure can be directed to a glass containing, on an oxide basis, SiO2 in the range of about 60 mol% to about 80 mol%, about 60 mol% to about 78 mol%, about 60 mol% to about 76 mol%, about 60 mol% to about 72 mol%, about 60 mol% to about 70 mol%, about 60 mol% to about 68 mol%, about 60 mol% to about 66 mol%, about 60 mol% to about 64 mol%, or about 60 mol% to about 62 mol% (including all ranges and subranges therebetween). In certain embodiments, the glass has a SiO 2 content in the range of about 61 mol % to about 80 mol %, e.g., about 62 mol % to about 80 mol %, about 63 mol % to about 80 mol %, about 64 mol % to about 80 mol %, about 65 mol % to about 80 mol %, about 66 mol % to about 80 mol %, about 67 mol % to about 80 mol %, about 68 mol % to about 80 mol %, about 69 mol % to about 80 mol %, about 70 mol % to about 80 mol %, about 71 mol % to about 80 mol %, about 72 mol % to about 80 mol %, about 73 mol % to about 80 mol %, about 74 mol % to about 80 mol %, about 75 mol % to about 80 mol %, about 76 mol % to about 80 mol %, about 77 mol % to about 80 mol %, about 78 mol % to about 80 mol %, about 79 mol % to about 80 mol %, about 80 mol % to about 80 mol %, about 81 mol % to about 80 mol %, about 82 mol % to about 80 mol %, about 83 mol % to about 80 mol %, about 84 mol % to about 80 mol %, about 85 mol % to about 80 mol %, about 86 mol % to about 80 mol %, about 87 mol % to about 80 mol %, about 88 mol % to about 80 mol %, about 89 mol % to about 80 0 mol%, about 71 mol% to about 80 mol%, about 72 mol% to about 80 mol%, about 73 mol% to about 80 mol%, about 74 mol% to about 80 mol%, about 75 mol% to about 80 mol%, about 76 mol% to about 80 mol%, about 77 mol% to about 80 mol%, or about 78 mol% to about 80 mol% (including all ranges and subranges therebetween).

[0048] In even further embodiments, exemplary glasses can include SiO2 in the range of about 61 mol% to about 73 mol%, e.g., about 61 mol% to about 72 mol%, about 61 mol% to about 71 mol%, about 61 mol% to about 70 mol%, about 61 mol% to about 69 mol%, about 61 mol% to about 68 mol%, about 61 mol% to about 67 mol%, about 61 mol% to about 66 mol%, about 61 mol% to about 65 mol%, about 61 mol% to about 64 mol%, about 61 mol% to about 63 mol%, or about 61 mol% to about 62 mol%, including all ranges and subranges therebetween.

[0049] Al2O3 is another glass former used to produce the glasses described herein. Al2O3 concentrations of about 9 mol percent or greater provide glasses with low liquidus temperatures and high viscosities, thereby increasing liquidus viscosities. The use of at least 9 mol percent Al2O3 also improves the annealing point and Young's modulus of the glass. To achieve a ratio (MgO + CaO + SrO + BaO) / Al2O3 of about 1 or greater, the Al2O3 concentration can be less than about 15 mol%. For example, the glass can include Al2O3 in an amount of about 9 mol% or greater, e.g., in the range of about 9 mol% to about 14 mol%, about 10 mol% to about 14 mol%, about 11 mol% to about 14 mol%, about 12 mol% to about 14 mol%, or about 13 mol% to about 14 mol%, including all ranges and subranges therebetween. In further embodiments, the glass can include Al2O3 in an amount in the range of about 9 mol% to about 13 mol%, in the range of about 9 mol% to about 12 mol%, in the range of about 9 mol% to about 11 mol%, or in the range of about 9 mol% to about 10 mol%, including all ranges and subranges therebetween.

[0050] B2O3 is both a glass former and a flux that aids in melting and lowers the melting temperature. B2O3 affects both the liquidus temperature and viscosity. Increasing B2O3 can increase the liquidus viscosity of the glass. To achieve these effects, the glass compositions disclosed herein can have a B2O3 concentration greater than or equal to 0 mole percent. As noted above, glass durability is important for LCD applications. Durability can be controlled to some extent by increasing the concentration of alkaline earth oxides, but can be significantly reduced by increasing the B2O3 content. Because increasing B2O3 decreases the annealing point, it can be helpful to maintain a low B2O3 content compared to concentrations typical for amorphous silicon display substrates. Thus, the glass can include B2O3 in an amount of about 12 mol% or less, e.g., in the range of about 0 mol% to about 12 mol%, e.g., in the range of about 0.1 mol% to about 12 mol%, about 0.5 mol% to about 12 mol%, about 1 mol% to about 12 mol%, about 2 mol% to about 12 mol%, about 3 mol% to about 12 mol%, about 4 mol% to about 12 mol%, about 5 mol% to about 12 mol%, about 6 mol% to about 12 mol%, about 7 mol% to about 12 mol%, about 8 mol% to about 12 mol%, about 9 mol% to about 12 mol%, about 10 mol% to about 12 mol%, or about 11 mol% to about 12 mol% (including all ranges and subranges therebetween).

[0051] In further embodiments, the glass can include B2O3 in an amount ranging from about 0 mol% to about 11 mol%, from about 0.1 mol% to about 10 mol%, from about 0.1 mol% to about 9 mol%, from about 0.1 mol% to about 8 mol%, from about 0.1 mol% to about 7 mol%, from about 0.1 mol% to about 6 mol%, from about 0.1 to about 5 mol%, from about 0.1 mol% to about 4 mol%, from about 0.1 mol% to about 3 mol%, from about 0.1 mol% to about 2 mol%, from about 0.1 mol% to about 1 mol%, or from about 0.1 mol% to about 0.5 mol%, including all ranges and subranges therebetween.

[0052] The glass can further include MgO in an amount of about 9 mol% or less, for example, in the range of about 0 mol% to about 9 mol%, for example, in the range of about 0.5 mol% to about 9 mol%, about 1 mol% to about 9 mol%, for example, in the range of about 2 mol% to about 9 mol%, about 3 mol% to about 9 mol%, about 4 mol% to about 9 mol%, about 5 mol% to about 9 mol%, about 6 mol% to about 9 mol%, or about 7 mol% to about 9 mol% (including all ranges and subranges therebetween). In further embodiments, the glass can further comprise MgO in an amount ranging from about 0 mol% to about 8 mol%, from about 0.5 mol% to about 7 mol%, from about 0.5 mol% to about 6 mol%, from about 0.5 mol% to about 5 mol%, from about 0.5 mol% to about 4 mol%, from about 0.5 mol% to about 3 mol%, from about 0.5 mol% to about 2 mol%, or from about 0.5 mol% to about 1 mol%, including all ranges and subranges therebetween.

[0053] The glass can further contain CaO in the range of about 3 mol% to about 12 mol%, for example, in the range of about 3 mol% to about 11 mol%, about 3 mol% to about 10 mol%, about 3 mol% to about 9 mol%, about 3 mol% to about 8 mol%, about 3 mol% to about 7 mol%, about 3 mol% to about 6 mol%, about 3 mol% to about 5 mol%, or about 3 mol% to about 4 mol%. In further embodiments, the glass can include CaO in an amount ranging 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 subranges therebetween.

[0054] The glass can further include SrO in an amount of about 5 mol% or less, for example, in the range of about 0 mol% to about 5 mol%, for example, in the range of about 0 mol% to about 4 mol%, in the range of about 0 mol% to about 3 mol%, in the range of about 0 mol% to about 2 mol%, or in the range of about 0 mol% to about 1 mol%. In further embodiments, the glass can include SrO in an amount ranging 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 subranges therebetween.

[0055] The glass can further include BaO in an amount of about 5 mol% or less, e.g., in the range of about 0 mol% to about 5 mol%, e.g., in the range of about 0 mol% to about 4 mol%, in the range of about 0 mol% to about 3 mol%, in the range of about 0 mol% to about 2 mol%, or in the range of about 0 mol% to about 1 mol%, including all ranges and subranges therebetween. In further embodiments, the glass can include BaO in an amount ranging 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. The glass can include RO (i.e., MgO, CaO, SrO, and / or BaO) such that (MgO+CaO+SrO+BaO) / Al2O3 is about 1.6 or less, e.g., in the range of about 1 to about 1.5, about 1 to about 1.4, about 1 to about 1.3, about 1 to about 1.2, or about 1 to about 1.1, including all ranges and subranges therebetween. In further embodiments, the glass can include RO in an amount such that (MgO+CaO+SrO+BaO) / Al2O3 is in the range of about 1.1 to about 1.6, about 1.2 to about 1.6, about 1.3 to about 1.6, about 1.4 to about 1.6, or about 1.5 to about 1.6, including all ranges and subranges therebetween.

[0056] As previously mentioned, a (MgO + CaO + SrO + BaO) / Al2O3 ratio of about 1 or greater can improve fining, i.e., the removal of gaseous inclusions from molten batch materials. This allows for more environmentally friendly fining. Accordingly, the glasses disclosed herein can include chemical fining agents. Suitable fining agents can include, but are not limited to, SnO2, As2O3, Sb2O3, F, Cl, and Br. In embodiments, the chemical fining agent can include one or more of SnO2, As2O3, Sb2O3, F, Cl, and / or Br at a concentration of about 0.5 mol% or less, e.g., about 0.45 mol% or less, about 0.4 mol% or less, about 0.35 mol% or less, about 0.3 mol% or less, or about 0.25 mol% or less. In embodiments, the glass can include any one or combination of SnO2, As2O3, Sb2O3, F, Cl, and / or Br in the range of about 0.01 mol% to about 0.4 mol%. In certain embodiments, the glass composition can include any one or combination of Fe2O3, CeO2, and / or MnO2 in the range of about 0.005 mol% to about 0.2 mol%.

[0057] As2O3 is an effective high-temperature fining agent for display glass, and in some embodiments described herein, As2O3 can be used for fining due to its excellent fining properties. However, As2O3 is toxic and requires special handling during the glass manufacturing process. Therefore, in embodiments, fining can be performed without using significant amounts of As2O3, i.e., the finished glass has a maximum of 0.05 mole percent As2O3. In various embodiments, As2O3 is not used in fining the glass. In such cases, the finished glass typically has a maximum of 0.005 mole percent As2O3 as a result of contaminants present in the batch materials and / or the equipment used to melt the batch materials.

[0058] While less toxic than As2O3, Sb2O3 is also toxic and requires special handling. Furthermore, Sb2O3 increases the density, CTE, and anneal point of the glass compared to glasses that use As2O3 or SnO2 as a fining agent. Thus, in certain embodiments, fining can be performed without significant amounts of Sb2O3, i.e., the finished glass has a maximum of 0.05 mole percent Sb2O3. In other embodiments, Sb2O3 is not intentionally used in fining the glass. In such cases, the finished glass typically has a maximum of 0.005 mole percent Sb2O3, resulting from contaminants present in the batch materials and / or the equipment used to melt the batch materials.

[0059] Although tin fining (i.e., SnO2 fining) is less effective than As2O3 and Sb2O3 fining, SnO2 is a ubiquitous material with no known harmful properties. Also, for many years, SnO2 has been a component of display glass manufactured using tin oxide electrodes during Joule melting of batch materials. The presence of SnO2 in display glass has not caused any known adverse effects in the manufacture of flat panel displays. However, high concentrations of SnO2 are undesirable because they can lead to the formation of crystalline defects in display glass. Therefore, the SnO2 concentration in the finished glass can be kept below 0.25 mole percent.

[0060] The high viscosity glasses described herein allow for high concentrations of SnO2 without adverse effects. For example, conventional wisdom suggests that glasses with high annealing points result in high melting temperatures. Such high melting temperatures can lead to an increased presence of inclusions in the respective glasses. To address the presence of such inclusions, fining agents can be added. However, glasses with low viscosities generally cannot tolerate the addition of SnO2 due to crystallization within the glass. However, exemplary glasses described herein can have higher viscosities that result in high forming temperatures. Thus, higher concentrations of fining agents can be added to the glass, resulting in fewer inclusions. Simply put, by changing the composition of exemplary glasses to produce higher processing temperatures, more fining agents can be added to remove inclusions before crystallization occurs. Thus, exemplary glasses can contain SnO2 in concentrations of about 0.001 mol% to about 0.5 mol% and have a T of about 1170°C or higher, about 1200°C or higher, about 1290°C or higher, or about 1300°C or higher. 35kP Representative glasses may contain SnO2 in a concentration ranging from about 0.001 mol% to about 0.5 mol%, and have a T of about 1530°C or higher, about 1600°C or higher, about 1670°C or higher, or about 1700°C or higher. 200PFurther, exemplary glasses may contain SnO2 in a concentration ranging from about 0.001 mol % to about 0.5 mol %, and have a liquidus temperature of about 1080°C or higher, about 1150°C or higher, or about 1290°C or higher. Such glasses, as described above, have a T 35kP and / or T 200P As previously mentioned, SnO2 can be incorporated into the glass from Joule melting using tin oxide electrodes and / or through batching with tin-containing materials such as SnO2, SnO, SnCO3, SnC2O2, etc.

[0061] Tin fining can be used alone or in combination with other fining techniques, as desired. For example, tin fining can be combined with halide fining, e.g., bromine fining. Other possible combinations include, but are not limited to, sulfate, sulfide, cerium oxide, mechanical bubbling, and / or vacuum fining in addition to tin fining. It is contemplated that these other fining techniques can be used alone. In embodiments, maintaining the (MgO+CaO+SrO+BaO) / Al2O3 and individual alkaline earth metal concentrations within the ranges described herein makes the fining process easier to perform and more effective.

[0062] The glass compositions disclosed herein can include transition metal oxides specifically added 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., Co3O4) in an amount sufficient to produce an average optical transmittance in the glass article of about 50% to about 90%, e.g., about 60% to about 85%, about 60% to about 83%, about 60% to about 81%, about 60% to about 79%, about 60% to about 77%, about 60% to about 75%, about 60% to about 73%, about 60% to about 71%, about 60% to about 69%, about 60% to about 67%, or about 60% to about 65%, over a wavelength range of about 450 nm to about 650 nm, as measured through a thickness of 0.7 mm with an optical power meter.

[0063] In further embodiments, the glass can have an average transmittance in the range of about 62% to about 90%, about 64% to about 90%, about 66% to about 90%, about 68% to about 90%, about 70% to about 90%, about 72% to about 90%, about 74% to about 90%, about 76% to about 90%, about 78% to about 90%, about 80% to about 90%, or about 82% to about 90%, including all ranges and subranges therebetween. As used herein, average transmittance refers to the average of all transmittances for a given glass article, such as a glass substrate, over the wavelength range described. See, for example, Figure 6, which shows the transmittance of several different compositions. Indeed, the data show that transmittance from 450 nanometers to 650 nanometers falls within + / - 5% of the average transmittance for a given sample, indicating a very flat transmittance response to wavelength over that wavelength range.

[0064] The glass may contain a SiO 2 content in the range of about 0 mol% to about 0.15 mol%, about 0.025 mol% to about 0.15 mol%, about 0.035 mol% to about 0.15 mol%, about 0.045 mol% to about 0.15 mol%, about 0.055 mol% to about 0.15 mol%, about 0.065 mol% to about 0.15 mol%, about 0.075 mol% to about 0.15 mol%, about 0.085 mol% to about 0.15 mol%, about 0.095 mol% to about 0.15 mol%, about 0.105 mol% to about 0.15 mol%, about 0.110 mol% to about 0.15 mol%, about 0.115 mol% to about 0.15 mol%, about 0.120 mol% to about 0.15 mol%, or about 0.125 mol% to about 1.5 mol% (including all ranges and subranges therebetween). In further embodiments, the glass can comprise NiO in the range of about 0 mol% to about 0.14 mol%, about 0 mol% to about 0.13 mol%, about 0 mol% to about 0.12 mol%, about 0 mol% to about 0.11 mol%, about 0 mol% to about 0.10 mol%, about 0 mol% to about 0.09 mol%, about 0 mol% to about 0.08 mol%, about 0 mol% to about 0.07 mol%, about 0 mol% to about 0.06 mol%, or about 0 mol% to about 0.05 mol%, including all ranges and subranges therebetween.

[0065] Alternatively, or in addition, the glass can include Co3O4 in a range of about 0 mol% to about 0.05 mol%, e.g., about 0 mol% to about 0.045 mol%, about 0 mol% to about 0.04 mol%, about 0 mol% to about 0.035 mol%, about 0 mol% to about 0.03 mol%, about 0 mol% to about 0.025 mol%, about 0 mol% to about 0.02 mol%, about 0 mol% to about 0.015 mol%, or about 0 mol% to about 0.01 mol%, including all ranges and subranges therebetween. In further embodiments, the glass can include Co3O4 in the range of about 0.01 mol% to about 0.05 mol%, about 0.015 mol% to about 0.05 mol%, about 0.02 mol% to about 0.05 mol%, about 0.025 mol% to about 0.05 mol%, about 0.03 mol% to about 0.05 mol%, about 0.035 mol% to about 0.05 mol%, about 0.04 mol% to about 0.05 mol%, or about 0.045 mol% to about 0.05 mol%, inclusive of all ranges and subranges therebetween. In certain embodiments, the glass can include Co3O4 in the range of about 0.005 mol% to about 0.05 mol%, e.g., about 0.01 mol% to about 0.04 mol%, inclusive of all ranges and subranges therebetween.

[0066] The glass can include Fe2O3 in an amount less than or equal to about 0.02 mol%, such as less than or equal to about 0.01 mol%. The reduced light transmittance glasses disclosed herein have a lightness value L* of less than about 94, e.g., in the range of about 83 to about 94, a red-green coordinate a*, when tested with a Cary 60 spectrometer from Agilent Technologies using FL2 illumination, a 10 degree observation angle, and a sample thickness of 0.7 mm. * is in the range of about -0.87 to about 0.02, yellow-blue coordinate b * can have color coordinates ranging from about −2.30 to about 1.85.

[0067] The annealing point (i.e., the annealing temperature) is the temperature at which the viscosity of the glass decreases to 10 13 Poise (10 13 dyne seconds / cm 2 ) is a temperature below 0.05°C. At such a viscosity, the glass is still too hard for significant external deformation without fracture, but soft enough to relax internal strains. The glasses disclosed herein can have an anneal point of about 700°C or higher, for example, in the range of about 700°C to about 810°C, about 710°C to about 810°C, about 720°C to about 810°C, about 730°C to about 810°C, about 740°C to about 810°C, about 750°C to about 810°C, about 760°C to about 810°C, about 770°C to about 810°C, about 780°C to about 810°C, about 790°C to about 810°C, or about 800°C to about 810°C (including all ranges and subranges therebetween).

[0068] In further embodiments, the glass can have an anneal point in the range of about 700°C to about 800°C, about 700°C to about 790°C, about 700°C to about 780°C, about 700°C to about 770°C, about 700°C to about 760°C, about 700°C to about 750°C, about 700°C to about 740°C, about 700°C to about 730°C, about 700°C to about 720°C, or about 700°C to about 710°C, including all ranges and subranges therebetween. The strain point is the point at which the viscosity of the glass decreases to 10 14.5The glass disclosed herein can have a strain point in the range of about 660°C to about 760°C, e.g., about 660°C to about 750°C, about 660°C to about 740°C, about 660°C to about 730°C, about 660°C to about 720°C, about 660°C to about 710°C, about 660°C to about 700°C, about 660°C to about 680°C, or about 660°C to about 670°C (including all ranges and subranges therebetween).

[0069] In further embodiments, the glass can have a strain point in the range of about 670°C to about 760°C, e.g., about 680°C to about 760°C, about 690°C to about 760°C, about 700°C to about 760°C, about 710°C to about 760°C, about 720°C to about 760°C, about 730°C to about 760°C, about 740°C to about 760°C, or about 750°C to about 760°C, including all ranges and subranges therebetween. In certain embodiments, the glass can have a strain point in the range of about 667°C to about 752°C, including all ranges and subranges therebetween. Young's modulus is a measure of the tensile or compressive stress (ie, force per unit area) and the resulting strain in the linear elastic region of the glass as a result of that force. The glasses disclosed herein can exhibit a Young's modulus of greater than about 69 GPa, e.g., in the range of about 69 GPa to about 85 GPa, about 70 GPa to about 85 GPa, about 71 GPa to about 85 GPa, about 72 GPa to about 85 GPa, about 73 GPa to about 85 GPa, about 74 GPa to about 85 GPa, about 75 GPa to about 85 GPa, about 76 GPa to about 85 GPa, about 77 GPa to about 85 GPa, about 78 GPa to about 85 GPa, about 79 GPa to about 85 GPa, about 80 GPa to about 85 GPa, about 81 GPa to about 85 GPa, about 82 GPa to about 85 GPa, about 83 GPa to about 85 GPa, or about 84 GPa to about 85 GPa (including all ranges and subranges therebetween).

[0070] In further embodiments, the glass can have a Young's modulus in the range of about 69 gigapascals (GPa) to about 84 GPa, e.g., in the range of about 69 GPa to about 83 GPa, in the range of about 69 GPa to about 82 GPa, in the range of about 69 GPa to about 81 GPa, in the range of about 69 GPa to about 80 GPa, in the range of about 69 GPa to about 79 GPa, in the range of about 69 GPa to about 78 GPa, in the range of about 69 GPa to about 77 GPa, in the range of about 69 GPa to about 76 GPa, in the range of about 69 GPa to about 75 GPa, in the range of about 69 GPa to about 74 GPa, in the range of about 69 GPa to about 73 GPa, in the range of about 69 GPa to about 72 GPa, in the range of about 69 GPa to about 71 GPa, or in the range of about 69 GPa to about 70 GPa (including all ranges and subranges therebetween).

[0071] In an embodiment, the temperature of the glass at a viscosity of about 35,000 poise (T 35kP ) can be about 1340°C or less, about 1330°C or less, about 1320°C or less, about 1310°C or less, about 1300°C or less, about 1280°C or less, about 1260°C or less, about 1240°C or less, about 1220°C or less, about 1200°C or less, or about 1180°C or less. For example, the glass may have a T in the range of about 1160°C to about 1340°C, about 1170°C to about 1340°C, about 1200°C to about 1340°C, about 1220°C to about 1340°C, about 1240°C to about 1340°C, about 1260°C to about 1340°C, about 1280°C to about 1340°C, about 1300°C to about 1340°C, or about 1320°C to about 1340°C (including all ranges and subranges therebetween). 35kP It can have:

[0072] In an embodiment, the temperature of the glass at a viscosity of about 200 poise (T 200P) is about 1700°C or less, for example, in the range of about 1530°C to about 1700°C, about 1540°C to about 1700°C, about 1550°C to about 1700°C, about 1560°C to about 1700°C, about 1570°C to about 1700°C, about 1580°C to about 1700°C, about 1590°C to about 1700°C, about 1600°C to about 1700°C, or about 1610°C to about 1700°C. , about 1620°C to about 1700°C, about 1630°C to about 1700°C, about 1640°C to about 1700°C, about 1650°C to about 1700°C, about 1660°C to about 1700°C, about 1670°C to about 1700°C, about 1680°C to about 1700°C, or about 1690°C to about 1700°C (including all ranges and subranges therebetween). In a further embodiment, T 200P can be in the range of about 1530°C to about 1690°C, about 1530°C to about 1680°C, about 1530°C to about 1660°C, about 1530°C to about 1650°C, about 1530°C to about 1640°C, about 1530°C to about 1630°C, about 1530°C to about 1620°C, about 1530°C to about 1610°C, about 1530°C to about 1600°C, about 1530°C to about 1590°C, about 1530°C to about 1580°C, about 1530°C to about 1570°C, about 1530°C to about 1560°C, about 1530°C to about 1150°C, or about 1530°C to about 1540°C (including all ranges and subranges therebetween).

[0073] The liquidus temperature of glass (T liq ) is the temperature at which crystalline phases cannot coexist in equilibrium with the glass. In embodiments, the glasses disclosed herein have a T in the range of about 1090°C to about 1290°C, e.g., about 1090°C to about 1260°C, about 1090°C to about 1230°C, about 1090°C to about 1200°C, about 1090°C to about 1180°C, about 1090°C to about 1160°C, about 1090°C to about 1140°C, or about 1090°C to about 1120°C. liq This ensures a minimal tendency of the compact to devitrify during the molding process. In a further embodiment, Tliq can be in the range of about 1100°C to about 1290°C, about 1120°C to about 1290°C, about 1140°C to about 1290°C, about 1160°C to about 1290°C, about 1180°C to about 1290°C, about 1200°C to about 1290°C, about 1220°C to about 1290°C, about 1240°C to about 1290°C, or about 1260°C to about 1290°C (including all ranges and subranges therebetween).

[0074] The glasses disclosed herein can exhibit a liquidus viscosity at the liquidus temperature in the range of about 69 kilopoise (kP) to about 630 kP, e.g., in the range of about 100 kP to about 500 kP, about 100 kP to about 400 kP, about 100 kP to about 300 kP, or about 100 kP to about 200 kP, including all ranges and subranges therebetween. In further embodiments, the glasses disclosed herein can include a liquidus viscosity in the range of about 200 kP to about 400 kP, or about 300 kP to about 400 kP, including all ranges and subranges therebetween. In an embodiment, an exemplary glass is T 35kP -T liq >0.25T 35kP It can indicate -225℃. In aspects, the densities of the glasses 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 densities can 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 subranges therebetween.

[0075] In one or more embodiments, the glasses disclosed herein have a viscosity of about 28×10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 28 x 10 -7 / ℃ ~ approx. 38×10 -7 / °C range, approximately 28 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 28 x 10 -7 / ℃ ~ approx. 34×10 -7 / °C range, approximately 28 x 10 -7 / ℃ ~ approx. 32×10 -7 / °C range, or approximately 28 x 10 -7 / ℃ ~ approx. 30×10 -7 / °C, including all ranges and subranges therebetween. In a further embodiment, the glass may have a coefficient of thermal expansion (over a temperature range of 0°C to 300°C) of about 30 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 32 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 34 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 36 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, or approximately 38 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C, including all ranges and subranges therebetween.

[0076] One or more particular embodiments can be directed to a glass comprising, on an oxide basis, a mole percent of SiO in the range of about 68 mol% to about 72 mol%, e.g., about 69 mol% to about 72 mol%, about 70 mol% to about 72 mol%, or about 71 mol% to about 72 mol%, including all ranges and subranges therebetween. In further embodiments, the glass can include SiO in the range of about 68 mol% to about 71 mol%, in the range of about 68 mol% to about 70 mol%, or in the range of about 68 mol% to about 69 mol%, including all ranges and subranges therebetween. The glass can include Al2O3 in a range of about 10 mol% to about 14 mol%, e.g., about 10.5 mol% to about 14 mol%, about 11 mol% to about 14 mol%, about 11.5 mol% to about 14 mol%, about 12 mol% to about 14 mol%, about 12.5 mol% to about 14 mol%, about 13 mol% to about 14 mol%, or about 13.5 mol% to about 14 mol% (including all ranges and subranges therebetween).

[0077] The glass can contain B2O3 in a range of 0 mol% or more to about 2 mol%, for example, in a range of about 0.1 mol% to about 2 mol%, about 0.2 mol% to about 2 mol%, about 0.4 mol% to about 2 mol%, about 0.6 mol% to about 2 mol%, about 0.8 mol% to about 2 mol%, about 1 mol% to about 2 mol%, about 1.2 mol% to about 2 mol%, about 1.4 mol% to about 2 mol%, about 1.6 mol% to about 2 mol%, or about 1.8 mol% to about 2 mol% (including all ranges and subranges therebetween). The glass can contain MgO in a range of about 3 mol% to about 9 mol%, e.g., about 3.5 mol% to about 9 mol%, about 4 mol% to about 9 mol%, about 4.5 mol% to about 9 mol%, about 5 mol% to about 9 mol%, about 5.5 mol% to about 9 mol%, about 6 mol% to about 9 mol%, about 6.5 mol% to about 9 mol%, about 7 mol% to about 9 mol%, about 7.5 mol% to about 9 mol%, about 8 mol% to about 9 mol%, or about 8.5 mol% to about 9 mol% (including all ranges and subranges therebetween).

[0078] The glass can include CaO in the range of about 3.5 mol% to about 6 mol%, e.g., about 3.75 mol% to about 6 mol%, about 4 mol% to about 6 mol%, about 4.5 mol% to about 6 mol%, about 5 mol% to about 6 mol%, or about 5.5 mol% to about 6 mol% (including all ranges and subranges therebetween).

[0079] The glass can include SrO in a range of about 1 mol% to about 2 mol%, e.g., about 1.2 mol% to about 2 mol%, about 1.4 mol% to about 2 mol%, about 1.6 mol% to about 2 mol%, or about 1.8 mol% to about 2 mol% (including all ranges and subranges therebetween). The glass can include BaO in the range of about 3 mol% to about 5 mol%, e.g., about 3.5 mol% to about 5 mol%, about 4 mol% to about 5 mol%, or about 4.5 mol% to about 5 mol% (including all ranges and subranges therebetween). The glass can contain RO (i.e., MgO, CaO, SrO, and BaO) such that (MgO+CaO+SrO+BaO) / Al2O3 is about 1 or greater, for example, in the range of about 1 to about 1.6, about 1 to about 1.5, about 1 to about 1.4, about 1 to about 1.3, or about 1 to about 1.2 (including all ranges and subranges therebetween).

[0080] In further embodiments, the glass can include an amount of RO such that (MgO+CaO+SrO+BaO) / Al2O3 is in the range of about 1.1 to about 1.6, e.g., in the range of about 1.2 to about 1.6, in the range of about 1.3 to about 1.6, in the range of about 1.4 to about 1.6, or in the range of about 1.5 to about 1.6, including all ranges and subranges therebetween. The glass can include NiO in the range of about 0.05 mol% to about 0.15 mol%, e.g., about 0.075 mol% to about 0.15 mol%, about 0.1 mol% to about 0.15 mol%, or about 0.125 mol% to about 0.15 mol%, including all ranges and subranges therebetween. The glass can include Co3O4 in the range of about 0.01 mol% to about 0.05 mol%, e.g., about 0.02 mol% to about 0.05 mol%, about 0.03 mol% to about 0.05 mol%, or about 0.04 mol% to about 0.05 mol%, including all ranges and subranges therebetween.

[0081] The glass can include Fe2O3 in an amount of about 0.02 mol% or less, such as about 0.01 mol% or less. The glass may be substantially free of alkali metal oxides. The glass can have an anneal point of about 800°C or higher, for example, in the range of about 800°C to about 810°C, about 802°C to about 810°C, about 804°C to about 810°C, about 806°C to about 810°C, or about 808°C to about 810°C (including all ranges and subranges therebetween). In further embodiments, the glass can have an anneal point in the range of about 800°C to about 808°C, in the range of about 800°C to about 806°C, in the range of about 800°C to about 804°C, or in the range of about 800°C to about 802°C, including all ranges and subranges therebetween. In certain embodiments, the glass can have an anneal point in the range of about 801°C to 805°C, including all ranges and subranges therebetween.

[0082] The glass may have a strain point in the range of about 740°C to about 760°C, e.g., about 740°C to about 758°C, about 740°C to about 756°C, about 740°C to about 754°C, about 740°C to about 752°C, about 740°C to about 750°C, about 740°C to about 748°C, about 740°C to about 746°C, about 740°C to about 744°C, or about 740°C to about 742°C (including all ranges and subranges therebetween). In further embodiments, the glass can have a strain point in the range of about 742°C to about 760°C, e.g., about 744°C to about 760°C, about 746°C to about 760°C, about 748°C to about 760°C, about 750°C to about 760°C, about 752°C to about 760°C, about 754°C to about 760°C, about 756°C to about 760°C, or about 758°C to about 760°C, including all ranges and subranges therebetween. In certain embodiments, the glass can have a strain point in the range of about 748°C to about 752°C, including all ranges and subranges therebetween.

[0083] The glass can have a Young's modulus of about 81 GPa or greater, for example, in the range of about 81 GPa to about 85 GPa, in the range of about 82 GPa to about 85 GPa, or in the range of about 84 GPa to about 85 GPa, including all ranges and subranges therebetween. In further embodiments, the glass can have a Young's modulus in the range of about 82 GPa to about 85 GPa, in the range of about 83 GPa to about 85 GPa, or in the range of about 84 GPa to about 85 GPa, including all ranges and subranges therebetween. In certain embodiments, the glass can have a Young's modulus in the range of about 81.9 GPa to about 84.4 GPa, including all ranges and subranges therebetween. The glass has a T of about 1700°C or less, for example, in the range of about 1680°C to about 1700°C, about 1682°C to about 1700°C, about 1684°C to about 1700°C, about 1686°C to about 1700°C, about 1688°C to about 1700°C, about 1690°C to about 1700°C, about 1692°C to about 1700°C, about 1694°C to about 1700°C, about 1696°C to about 1700°C, or about 1698°C to about 1700°C (including all ranges and subranges therebetween). 200P It can have:

[0084] In a further embodiment, T 200P can be in the range of about 1680°C to about 1698°C, about 1680°C to about 1696°C, about 1680°C to about 1694°C, about 1680°C to about 1692°C, about 1680°C to about 1690°C, about 1680°C to about 1688°C, about 1680°C to about 1686°C, about 1680°C to about 1684°C, or about 1680°C to about 1682°C (including all ranges and subranges therebetween). 200P can be in the range of about 1681°C to about 1696°C, including all ranges and subranges therebetween. In an embodiment, the temperature of the glass at a viscosity of about 35,000 poise (T 35kP ) can be in the range of about 1290°C to about 1310°C, about 1300°C to about 1310°C, about 1302°C to about 1310°C, about 1304°C to about 1310°C, about 1306°C to about 1310°C, or about 1308°C to about 1310°C (including all ranges and subranges therebetween).

[0085] In further embodiments, the glass has a T in the range of about 1290°C to about 1308°C, about 1290°C to about 1306°C, about 1290°C to about 1304°C, about 1290°C to about 1302°C, about 1290°C to about 1300°C, about 1290°C to about 1298°C, about 1290°C to about 1296°C, about 1290°C to about 1294°C, or about 1290°C to about 1292°C, including all ranges and subranges therebetween. 35kP In certain embodiments, T 35kP The temperature can be in the range of about 1290°C to about 1305°C, including all ranges and subranges therebetween. In embodiments, the glass has a T in the range of about 1195°C to about 1270°C, e.g., about 1195°C to about 1260°C, about 1195°C to about 1250°C, about 1195°C to about 1240°C, about 1195°C to about 1220°C, or about 1195°C to about 1210°C, including all ranges and subranges therebetween. liq It can have: In a further embodiment, T liq can be in the range of about 1200°C to about 1270°C, about 1210°C to about 1270°C, about 1220°C to about 1270°C, about 1240°C to about 1270°C, or about 1260°C to about 1270°C (including all ranges and subranges therebetween).

[0086] The glass can exhibit a liquidus viscosity at the liquidus temperature in the range of about 69 kP to about 350 kP, e.g., about 100 kP to about 350 kP, about 120 kP to about 350 kP, about 140 kP to about 350 kP, about 160 kP to about 350 kP, about 180 kP to about 350 kP, about 200 kP to about 350 kP, about 220 kP to about 350 kP, about 240 kP to about 350 kP, about 260 kP to about 350 kP, about 280 kP to about 350 kP, about 300 kP to about 350 kP, or about 320 kP to about 350 kP (including all ranges and subranges therebetween).

[0087] In further embodiments, the glass can have a liquidus viscosity in the range of about 69 kP to about 350 kP, about 69 kP to about 320 kP, about 69 kP to about 300 kP, about 69 kP to about 280 kP, about 69 kP to about 260 kP, about 69 kP to about 260 kP, about 69 kP to about 240 kP, about 69 kP to about 220 kP, about 69 kP to about 200 kP, about 69 kP to about 180 kP, about 69 kP to about 160 kP, about 69 kP to about 140 kP, about 69 kP to about 120 kP, or about 69 kP to about 100 kP, including all ranges and subranges therebetween. The glass is approximately 29 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 39×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 38×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 37×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 35×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 34×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 33×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 32×10 -7 / °C range, approximately 29 x 10 -7 / ℃ ~ approx. 31×10 -7 / °C range, or approximately 29 x 10 -7 / ℃ ~ approx. 30×10 -7 / °C, including all ranges and subranges therebetween.

[0088] In a further embodiment, the glass is about 30×10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 31 x 10 -7 / ℃ ~ approx. 36×10-7 / °C range, approximately 32 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 34 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, or approximately 35 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C, including all ranges and subranges therebetween. Glass is approximately 2.5g / cc 3 ~Approx. 2.62g / cc 3 range, approximately 2.55g / cc 3 ~Approx. 2.62g / cc 3 range, or about 2.6 g / cc 3 ~Approx. 2.66g / cc 3 (including all ranges and subranges therebetween).

[0089] The glass can have an average transmittance in the range of about 60% to about 80%, e.g., about 62% to about 80%, about 64% to about 80%, about 66% to about 80%, about 68% to about 80%, about 70% to about 80%, about 72% to about 80%, about 74% to about 80%, about 76% to about 80%, or about 78% to about 80% (including all ranges and subranges therebetween). One or more other specific embodiments can be directed to glasses comprising, on an oxide basis, SiO in a mole percent range of about 66 mol% to about 71 mol%, e.g., about 66.5 mol% to about 71 mol%, about 67 mol% to about 71 mol%, about 67.5 mol% to about 71 mol%, about 68 mol% to about 71 mol%, about 68.5 mol% to about 71 mol%, about 69 mol% to about 71 mol%, about 69.5 mol% to about 71 mol%, about 70 mol% to about 71 mol%, or about 70.5 mol% to about 71 mol%, including all ranges and subranges therebetween.

[0090] The glass can include Al2O3 in the range of about 9 mol% to about 12 mol%, e.g., in the range of about 9.5 mol% to about 12 mol%, in the range of about 10 mol% to about 12 mol%, in the range of about 10.5 mol% to about 12 mol%, in the range of about 11 mol% to about 12 mol%, or in the range of about 11.5 mol% to about 12 mol%, including all ranges and subranges therebetween. The glass can include B2O3 in a range of about 7 mol% to about 12 mol%, e.g., about 7.5 mol% to about 12 mol%, about 8 mol% to about 12 mol%, about 8.5 mol% to about 12 mol%, about 9 mol% to about 12 mol%, about 9.5 mol% to about 12 mol%, about 10 mol% to about 12 mol%, about 10.5 mol% to about 12 mol%, about 11 mol% to about 12 mol%, or about 11.5 mol% to about 12 mol% (including all ranges and subranges therebetween).

[0091] The glass can include MgO in the range of about 0.9 mol% to about 2.0 mol%, e.g., about 1 mol% to about 2 mol%, about 1.2 mol% to about 2 mol%, about 1.4 mol% to about 2 mol%, about 1.6 mol% to about 2 mol%, or about 1.8 mol% to about 2 mol% (including all ranges and subranges therebetween). The glass can contain CaO in a range of about 7 mol% to about 11.5 mol%, e.g., about 7.5 mol% to about 11.5 mol%, about 8 mol% to about 11.5 mol%, about 8.5 mol% to about 11.5 mol%, about 9 mol% to about 11.5 mol%, about 9.5 mol% to about 11.5 mol%, about 10 mol% to about 11.5 mol%, about 10.5 mol% to about 11.5 mol%, or about 11 mol% to about 11.5 mol% (including all ranges and subranges therebetween).

[0092] The glass can include SrO in a range of about 0.5 mol % to about 1.1 mol %, e.g., about 0.6 mol % to about 1.1 mol %, about 0.7 mol % to about 1.1 mol %, about 0.8 mol % to about 1.1 mol %, about 0.9 mol % to about 1.1 mol %, or about 1 mol % to about 1.1 mol % (including all ranges and subranges therebetween). The glass may contain BaO in the range of about 0 to about 0.1 mol %. For example, the glass may contain no BaO. The glass can include RO (i.e., MgO, CaO, SrO, and BaO) such that (MgO+CaO+SrO+BaO) / Al2O3 can be in the range of about 1 to about 1.2, or in the range of about 1 to about 1.1, including all ranges and subranges therebetween.

[0093] The glass can include NiO in the range of about 0.05 mol% to about 0.15 mol%, e.g., about 0.075 mol% to about 0.15 mol%, about 0.1 mol% to about 0.15 mol%, or about 0.125 mol% to about 0.15 mol%, including all ranges and subranges therebetween. The glass can include Co3O4 in the range of about 0.01 mol% to about 0.05 mol%, e.g., about 0.02 mol% to about 0.05 mol%, about 0.03 mol% to about 0.05 mol%, or about 0.04 mol% to about 0.05 mol%, including all ranges and subranges therebetween.

[0094] The glass can include Fe2O3 in an amount of about 0.02 mol% or less, such as about 0.01 mol% or less. The glass may be free of alkali metal oxides. The glass can have an anneal point in the range of about 720°C to about 750°C, such as about 730°C to about 750°C, or about 740°C to about 750°C, including all ranges and subranges therebetween. In further embodiments, the glass can have an anneal point in the range of about 720°C to about 740°C, or about 720°C to about 730°C, including all ranges and subranges therebetween. In certain embodiments, the glass can have an anneal point in the range of about 723°C to 745°C, including all ranges and subranges therebetween.

[0095] The glass can have a strain point in the range of about 660°C to about 700°C, e.g., about 665°C to about 700°C, about 670°C to about 700°C, about 675°C to about 700°C, about 680°C to about 700°C, about 685°C to about 700°C, about 690°C to about 700°C, or about 695°C to about 700°C (including all ranges and subranges therebetween). In certain embodiments, the glass can have a strain point in the range of about 667°C to about 693°C (including all ranges and subranges therebetween). The glass can have a Young's modulus in the range of about 69 to about 78 GPa, e.g., about 69 GPa to about 76 GPa, about 69 GPa to about 74 GPa, or about 69 GPa to about 72 GPa (including all ranges and subranges therebetween). In further embodiments, the glass can have a Young's modulus in the range of about 72 GPa to about 78 GPa, about 74 GPa to about 78 GPa, or about 76 GPa to about 78 GPa (including all ranges and subranges therebetween). In particular embodiments, the glass can have a Young's modulus of about 81.9 GPa to about 84.4 GPa (including all ranges and subranges therebetween).

[0096] The glass has a T of about 1680°C or less, for example, in the range of about 1590°C to about 1680°C, about 1600°C to about 1680°C, about 1610°C to about 1680°C, about 1620°C to about 1680°C, about 1630°C to about 1680°C, about 1640°C to about 1680°C, about 1650°C to about 1680°C, about 1660°C to about 1680°C, or about 1670°C to about 1680°C (including all ranges and subranges therebetween). 200P may include: In a further embodiment, T 200P can be in the range of about 1590°C to about 1670°C, about 1590°C to about 1660°C, about 1590°C to about 1650°C, about 1590°C to about 1640°C, about 1590°C to about 1630°C, about 1590°C to about 1620°C, about 1590°C to about 1610°C, or about 1590°C to about 1600°C (including all ranges and subranges therebetween). 200P The temperature can range from about 1590°C to about 1675°C.

[0097] In an embodiment, the temperature of the glass at a viscosity of about 35,000 poise (T 35kP ) can be in the range of about 1210°C to about 1260°C, about 1210°C to about 1250°C, about 1210°C to about 1240°C, about 1210°C to about 1230°C, or about 1210°C to about 1220°C, including all ranges and subranges therebetween. In further embodiments, the glass has a T of about 1220°C to about 1260°C, about 1230°C to about 1260°C, about 1240°C to about 1260°C, or about 1250°C to about 1260°C, including all ranges and subranges therebetween. 35kP In certain embodiments, T 35kP The temperature can range from about 1216°C to about 1255°C, including all ranges and subranges therebetween. In embodiments, the glass has a T in the range of about 1090°C to about 1170°C, e.g., about 1090°C to about 1160°C, about 1090°C to about 1150°C, about 1090°C to about 1140°C, about 1090°C to about 1120°C, or about 1090°C to about 1110°C, including all ranges and subranges therebetween. liq may include:

[0098] In a further embodiment, T liq can be in the range of about 1100°C to about 1170°C, about 1110°C to about 1170°C, about 1120°C to about 1170°C, about 1140°C to about 1170°C, or about 1160°C to about 1170°C (including all ranges and subranges therebetween). The glass can exhibit a liquidus viscosity at the liquidus temperature in the range of about 200 kP to about 630 kP, e.g., in the range of about 300 kP to about 630 kP, in the range of about 400 kP to about 630 kP, or in the range of about 500 kP to about 630 kP (including all ranges and subranges therebetween). In further embodiments, the glass can have a liquidus viscosity in the range of about 250 kP to about 630 kP, about 300 kP to about 630 kP, about 350 kP to about 630 kP, about 400 kP to about 630 kP, about 450 kP to about 630 kP, about 500 kP to 630 kP, or about 550 kP to about 630 kP, including all ranges and subranges therebetween.

[0099] The glass is approximately 33 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 39×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 38×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 37×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 35×10 -7 / °C range, approximately 33 x 10-7 / ℃ ~ approx. 34×10 -7 The linear thermal expansion coefficient (over the temperature range 0°C to 300°C) is shown in the range / °C, including all ranges and subranges therebetween. In a further embodiment, the glass has a thickness of about 34×10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 35 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 36 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 37 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 38 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, or approximately 39 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C, including all ranges and subranges therebetween.

[0100] Glass is approximately 2.3g / cc 3 ~about 2.5g / cc 3 range, for example, about 2.35 g / cc 3 ~about 2.5g / cc 3 range, approximately 2.4g / cc 3 ~about 2.5g / cc 3 range, approximately 2.45g / cc 3 ~about 2.5g / cc 3 In a particular embodiment, the glass may have a density in the range of about 2.34 g / cc (including all ranges and subranges therebetween). 3 ~Approx. 2.45g / cc 3 The density range can include: The glass can have an average transmittance in the range of about 64% to about 82%, e.g., about 64% to about 80%, about 64% to about 78%, about 64% to about 76%, about 64% to about 74%, about 64% to about 72%, about 64% to about 70%, about 64% to about 68%, or about 64% to about 66% (including all ranges and subranges therebetween). In further embodiments, the glass can have an average transmittance in the range of about 66% to about 82%, about 68% to about 82%, about 70% to about 82%, about 72% to about 82%, about 74% to about 82%, about 76% to about 82%, about 78% to about 82%, or about 80% to about 82%, including all ranges and subranges therebetween.

[0101] Still other specific embodiments can be directed to glasses containing SiO in the range of about 61 mol% to about 68 mol%, e.g., about 61.5 mol% to about 68 mol%, about 62 mol% to about 68 mol%, about 62.5 mol% to about 68 mol%, about 63 mol% to about 68 mol%, about 63.5 mol% to about 68 mol%, about 64 mol% to about 68 mol%, about 64.5 mol% to about 68 mol%, about 65 mol% to about 68 mol%, about 65.5 mol% to about 68 mol%, about 66 mol% to about 68 mol%, about 66.5 mol% to about 68 mol%, about 67 mol% to about 68 mol%, or about 67.5 mol% to about 68 mol%, including all ranges and subranges therebetween. The glass can include Al2O3 in the range of about 11 mol% to about 14 mol%, e.g., in the range of about 11.5 mol% to about 14 mol%, in the range of about 12 mol% to about 14 mol%, in the range of about 12.5 mol% to about 14 mol%, in the range of about 13 mol% to about 14 mol%, or in the range of about 13.5 mol% to about 14 mol%, including all ranges and subranges therebetween.

[0102] The glass can include B2O3 in a range of about 6 mol% to about 8.5 mol%, e.g., in a range of about 6.5 mol% to about 8.5 mol%, in a range of about 7 mol% to about 8.5 mol%, in a range of about 7.5 mol% to about 8.5 mol%, or in a range of about 8 mol% to about 8.5 mol%, including all ranges and subranges therebetween. The glass can include MgO in the range of about 3.5 mol% to about 6.0 mol%, e.g., about 4 mol% to about 6.0 mol%, about 4.5 mol% to about 6.0 mol%, about 5 mol% to about 6.0 mol%, or about 5.5 mol% to about 6 mol% (including all ranges and subranges therebetween).

[0103] The glass can include CaO in the range of about 5 mol% to about 7 mol%, e.g., about 5.5 mol% to about 7 mol%, about 6 mol% to about 7 mol%, or about 6.5 mol% to about 7 mol% (including all ranges and subranges therebetween). The glass can include SrO in the range of about 3 mol% to about 5 mol%, e.g., about 3.5 mol% to about 5 mol%, about 4 mol% to about 5 mol%, or about 4.5 mol% to about 5 mol% (including all ranges and subranges therebetween). The glass may contain BaO in the range of about 0 to about 0.1 mol %. For example, the glass may contain no BaO. The glass can include RO (i.e., MgO, CaO, SrO, and BaO) such that (MgO+CaO+SrO+BaO) / Al2O3 can be in the range of about 1.05 to about 1.3, in the range of about 1.1 to about 1.3, or in the range of about 1.2 to about 1.3, including all ranges and subranges therebetween.

[0104] The glass may be substantially free of alkali metal oxides. The glass can have an anneal point in the range of about 700°C to about 760°C, e.g., about 700°C to about 750°C, about 700°C to about 740°C, about 700°C to about 730°C, about 700°C to about 720°C, or about 700°C to about 710°C (including all ranges and subranges therebetween). The glass can include NiO in the range of about 0.05 mol% to about 0.15 mol%, e.g., about 0.075 mol% to about 0.15 mol%, about 0.1 mol% to about 0.15 mol%, or about 0.125 mol% to about 0.15 mol%, including all ranges and subranges therebetween. The glass can include Co3O4 in the range of about 0.01 mol% to about 0.05 mol%, e.g., about 0.02 mol% to about 0.05 mol%, about 0.03 mol% to about 0.05 mol%, or about 0.04 mol% to about 0.05 mol%, including all ranges and subranges therebetween.

[0105] The glass can include Fe2O3 in an amount of about 0.02 mol% or less, such as about 0.01 mol% or less. The glass may be free of alkali metal oxides. In further embodiments, the glass can have an anneal point in the range of about 710°C to about 760°C, about 720°C to about 760°C, about 730°C to about 760°C, about 740°C to about 760°C, or about 750°C to about 760°C, including all ranges and subranges therebetween. In certain embodiments, the glass can have an anneal point in the range of about 713°C to 754°C, including all ranges and subranges therebetween. The glass can have a strain point in the range of about 670°C to about 710°C, e.g., in the range of about 675°C to about 710°C, in the range of about 680°C to about 710°C, in the range of about 685°C to about 710°C, in the range of about 690°C to about 710°C, or in the range of about 700°C to about 710°C (including all ranges and subranges therebetween). In further embodiments, the glass can have a strain point in the range of about 670°C to about 700°C, in the range of about 670°C to about 690°C, or in the range of about 670°C to about 680°C, including all ranges and subranges therebetween. In certain embodiments, the glass can have a strain point in the range of about 676°C to about 701°C, including all ranges and subranges therebetween.

[0106] The glass can have a Young's modulus in the range of about 75 to about 81 GPa, e.g., about 76 GPa to about 81 GPa, about 77 GPa to about 81 GPa, about 78 GPa to about 81 GPa, or about 79 GPa to about 81 GPa (including all ranges and subranges therebetween). In further embodiments, the glass can have a Young's modulus in the range of about 75 GPa to about 79 GPa, about 75 GPa to about 78 GPa, about 75 GPa to about 77 GPa, or about 75 GPa to about 76 GPa (including all ranges and subranges therebetween). In certain embodiments, the glass can have a Young's modulus in the range of about 78.8 GPa to about 80.6 GPa (including all ranges and subranges therebetween). The glass has a T of about 1680°C or less, for example, in the range of about 1530°C to about 1610°C, about 1530°C to about 1600°C, about 1530°C to about 1590°C, about 1530°C to about 1580°C, about 1530°C to about 1570°C, about 1530°C to about 1560°C, about 1530°C to about 1550°C, or about 1530°C to about 1540°C (including all ranges and subranges therebetween). 200P It can have:

[0107] In a further embodiment, T 200P can be in the range of about 1540°C to about 1610°C, about 1550°C to about 1610°C, about 1560°C to about 1610°C, about 1570°C to about 1610°C, about 1580°C to about 1610°C, or about 1590°C to about 1610°C (including all ranges and subranges therebetween). 200P The temperature can range from about 1530°C to about 1606°C, including all ranges and subranges therebetween. In an embodiment, the temperature of the glass at a viscosity of about 35,000 poise (T 35kP) can be in the range of about 1170°C to about 1240°C, about 1180°C to about 1240°C, about 1200°C to about 1240°C, about 1210°C to about 1240°C, about 1220°C to about 1240°C, or about 1230°C to about 1240°C, including all ranges and subranges therebetween. In further embodiments, the glass has a T of about 1170°C to about 1230°C, about 1170°C to about 1220°C, about 1170°C to about 1210°C, about 1170°C to about 1200°C, about 1170°C to about 1190°C, or about 1170°C to about 1180°C, including all ranges and subranges therebetween. 35kP In certain embodiments, T 35kP can be in the range of about 1179°C to about 1237°C, including all ranges and subranges therebetween.

[0108] In embodiments, the glass has a T in the range of about 1125°C to about 1155°C, e.g., about 1125°C to about 1150°C, about 1125°C to about 1145°C, about 1125°C to about 1140°C, about 1125°C to about 1135°C, or about 1125°C to about 1130°C, including all ranges and subranges therebetween. liq It can have: In a further embodiment, T liq can be in the range of about 1130°C to about 1155°C, about 1135°C to about 1155°C, about 1140°C to about 1155°C, about 1145°C to about 1155°C, or about 1150°C to about 1155°C (including all ranges and subranges therebetween).

[0109] The glass can exhibit a liquidus viscosity at the liquidus temperature in the range of about 120 kP to about 270 kP, e.g., about 160 kP to about 270 kP, about 200 kP to about 270 kP, or about 250 kP to about 270 kP, including all ranges and subranges therebetween. In further embodiments, the glass can include a liquidus viscosity in the range of about 120 kP to about 250 kP, about 120 kP to about 200 kP, or about 120 kP to about 160 kP, including all ranges and subranges therebetween. The glass is approximately 33 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, or approximately 33 x 10 -7 / ℃ ~ approx. 39×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 38×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 37×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 35×10 -7 / °C range, or approximately 33 x 10 -7 / ℃ ~ approx. 34×10 -7 / °C, including all ranges and subranges therebetween. In a further embodiment, the glass may have a linear coefficient of thermal expansion (over a temperature range of 0°C to 300°C) of about 34 x 10 -7 / ℃ ~ approx. 35×10 -7 / °C, including all ranges and subranges therebetween.

[0110] Glass is approximately 2.45g / cc 3 ~Approx. 2.52g / cc 3 range, for example, about 2.47 g / cc 3 ~Approx. 2.52g / cc 3 range, or approximately 2.49 g / cc 3 ~Approx. 2.52g / cc 3 In a particular embodiment, the glass may have a density in the range of about 2.48 g / cc (including all ranges and subranges therebetween). 3 ~Approx. 2.51g / cc 3 The density range can include: The glass can have an average transmittance in the range of about 63% to about 80%, e.g., about 63% to about 78%, about 63% to about 76%, about 63% to about 74%, about 63% to about 72%, about 63% to about 70%, about 63% to about 68%, or about 63% to about 66%, including all ranges and subranges therebetween. In further embodiments, the glass can have an average transmittance in the range of about 66% to about 80%, about 68% to about 80%, about 70% to about 80%, about 72% to about 80%, about 74% to about 80%, or about 76% to about 80%, or about 78% to about 80%, including all ranges and subranges therebetween.

[0111] One or more other embodiments of the present disclosure can be directed to glasses comprising SiO in the range of about 66 mol% to about 69 mol%, e.g., in the range of about 66.5 mol% to about 69 mol%, in the range of about 67 mol% to about 69 mol%, in the range of about 67.5 mol% to about 69 mol%, in the range of about 68 mol% to about 69 mol%, or in the range of about 68.5 mol% to about 69 mol%, including all ranges and subranges therebetween. The glass can include Al2O3 in the range of about 12 mol% to about 14 mol%, e.g., about 12.2 mol% to about 14 mol%, about 12.4 mol% to about 14 mol%, for example, about 12.6 mol% to about 14 mol%, about 12.8 mol% to about 14 mol%, for example, about 13 mol% to about 14 mol%, about 13.2 mol% to about 14 mol%, about 13.4 mol% to about 14 mol%, about 13.6 mol% to about 14 mol%, or about 13.8 mol% to about 14 mol% (including all ranges and subranges therebetween).

[0112] The glass can further include B2O3 in the range of about 4 mol% to about 5 mol%, e.g., in the range of about 4.2 mol% to about 5 mol%, in the range of about 4.4 mol% to about 5 mol%, in the range of about 4.6 mol% to about 5 mol%, or in the range of about 4.8 mol% to about 5 mol%, including all ranges and subranges therebetween. The glass can further contain MgO in the range of about 4 mol% to about 6 mol%, for example, in the range of about 4.2 mol% to about 6 mol%, about 4.4 mol% to about 6 mol%, about 4.6 mol% to about 6 mol%, about 4.8 mol% to about 6 mol%, about 5 mol% to about 6 mol%, about 5.2 mol% to about 6 mol%, about 5.4 mol% to about 6 mol%, about 5.6 mol% to about 6 mol%, or about 5.8 mol% to about 6 mol%. In further embodiments, the glass can include MgO in an amount ranging 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 subranges therebetween. In even further embodiments, the glass can include MgO in an amount ranging 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 subranges therebetween. In certain embodiments, the glass may include MgO in the range of about 4.5 mol % to about 5.3 mol %, including all ranges and subranges therebetween.

[0113] The glass can contain CaO in a range of about 5 mol% to about 7 mol%, e.g., about 5.2 mol% to about 7 mol%, about 5.4 mol% to about 7 mol%, about 5.6 mol% to about 7 mol%, about 5.8 mol% to about 7 mol%, about 6 mol% to about 7 mol%, about 6.2 mol% to about 7 mol%, about 6.4 mol% to about 7 mol%, about 6.6 mol% to about 7 mol%, or about 6.8 mol% to about 7 mol% (including all ranges and subranges therebetween). In further embodiments, the glass can comprise CaO in the range of about 5 mol% to about 6.8 mol%, about 5 mol% to about 6.6 mol%, about 5 mol% to about 6.4 mol%, about 5 mol% to about 6.2 mol%, about 5 mol% to about 6 mol%, about 5 mol% to about 5.8 mol%, about 5 mol% to about 5.6 mol%, about 5 mol% to about 5.4 mol%, or about 5 mol% to about 5.2 mol%, inclusive of all ranges and subranges therebetween. In certain embodiments, the glass can comprise CaO in the range of about 5.5 mol% to about 6.5 mol%, inclusive of all ranges and subranges therebetween.

[0114] The glass can include SrO in an amount ranging from about 1.25 mol% to about 3.6 mol%, e.g., 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 subranges therebetween. In certain embodiments, the glass can include SrO in an amount ranging from about 1.5 mol% to about 3.6 mol%, including all ranges and subranges therebetween. The glass can include BaO in the range of about 0.5 mol% to about 2 mol%, e.g., about 0.75 mol% to about 2 mol%, about 1 mol% to about 2 mol%, about 1.25 mol% to about 2 mol%, about 1.5 mol% to about 2 mol%, or about 1.75 mol% to about 2 mol%, inclusive of all ranges and subranges therebetween. In certain embodiments, the glass can include BaO in an amount in the range of about 0.7 mol% to about 1.8 mol%, inclusive of all ranges and subranges therebetween.

[0115] The glass can include RO (i.e., MgO, CaO, SrO, and BaO) such that (MgO+CaO+SrO+BaO) / Al2O3 can be in the range of about 1.10 to about 1.14, in the range of about 1.12 to about 1.14, or in the range of about 1.13 to about 1.14, including all ranges and subranges therebetween. The glass can include NiO in the range of about 0.05 mol% to about 0.15 mol%, e.g., about 0.075 mol% to about 0.15 mol%, about 0.1 mol% to about 0.15 mol%, or about 0.125 mol% to about 0.15 mol%, including all ranges and subranges therebetween. The glass can include Co3O4 in the range of about 0.01 mol% to about 0.05 mol%, e.g., about 0.02 mol% to about 0.05 mol%, about 0.03 mol% to about 0.05 mol%, or about 0.04 mol% to about 0.05 mol%, including all ranges and subranges therebetween.

[0116] The glass can include Fe2O3 in an amount of about 0.02 mol% or less, such as about 0.01 mol% or less. The glass may be substantially free of alkali metal oxides. The glass can have an anneal point in the range of about 760°C to about 765°C, for example, in the range of about 763°C to about 765°C. The glass can have a strain point in the range of about 700° C. to about 720° C., for example, in the range of about 710° C. to about 720° C., including all ranges and subranges therebetween. The glass can have a Young's modulus in the range of about 75 to about 83 GPa, e.g., about 76 GPa to about 83 GPa, about 78 GPa to about 83 GPa, or about 80 GPa to about 83 GPa (including all ranges and subranges therebetween). In further embodiments, the glass can have a Young's modulus in the range of about 75 GPa to about 80 GPa, about 75 GPa to about 78 GPa, or about 75 GPa to about 76 GPa (including all ranges and subranges therebetween). In particular embodiments, the glass can have a Young's modulus in the range of about 78.3 GPa to about 82.4 GPa (including all ranges and subranges therebetween).

[0117] The glass has a T of about 1680°C or less, for example, in the range of about 1600°C to about 1680°C, about 1610°C to about 1680°C, about 1620°C to about 1680°C, or about 1630°C to about 1680°C, about 1640°C to about 1680°C, about 1650°C to about 1680°C, about 1660°C to about 1680°C, or about 1670°C to about 1680°C (including all ranges and subranges therebetween). 200P In a further embodiment, T 200P can be in the range of about 1600°C to about 1670°C, about 1600°C to about 1660°C, about 1600°C to about 1650°C, about 1600°C to about 1640°C, or about 1600°C to about 1630°C (including all ranges and subranges therebetween). 200P can be in the range of about 1608°C to about 1639°C, including all ranges and subranges therebetween. In an embodiment, the temperature of the glass at a viscosity of about 35,000 poise (T 35kP ) can be in the range of about 1230°C to about 1270°C, about 1240°C to about 1270°C, about 1250°C to about 1270°C, or about 1260°C to about 1270°C, including all ranges and subranges therebetween. In further embodiments, the glass has a T of about 1230°C to about 1260°C, about 1230°C to about 1250°C, or about 1230°C to about 1240°C, including all ranges and subranges therebetween. 35kPIn certain embodiments, T 35kP can be in the range of about 1238°C to about 1264°C, including all ranges and subranges therebetween.

[0118] In embodiments, the glass has a T in the range of about 1135°C to about 1185°C, e.g., about 1135°C to about 1175°C, about 1135°C to about 1165°C, about 1135°C to about 1155°C, or about 1135°C to about 1145°C, including all ranges and subranges therebetween. liq In a further embodiment, T liq can be in the range of about 1145°C to about 1185°C, about 1155°C to about 1185°C, about 1165°C to about 1185°C, or about 1175°C to about 1185°C (including all ranges and subranges therebetween). The glass can exhibit a liquidus viscosity at the liquidus temperature in the range of about 200 kP to about 390 kP, e.g., about 250 kP to about 390 kP, about 300 kP to about 390 kP, or about 350 kP to about 390 kP, including all ranges and subranges therebetween. In further embodiments, the glass can include a liquidus viscosity in the range of about 200 kP to about 350 kP, about 200 kP to about 300 kP, or about 200 kP to about 250 kP, including all ranges and subranges therebetween.

[0119] The glass is approximately 33 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 39×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 38×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 37×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 36×10 -7 / °C range, approximately 33 x 10 -7 / ℃ ~ approx. 35×10 -7 / °C range, or approximately 33 x 10 -7 / ℃ ~ approx. 34×10 -7 / °C, including all ranges and subranges therebetween. In a further embodiment, the glass may have a linear coefficient of thermal expansion (over a temperature range of 0°C to 300°C) of about 34 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 35 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 36 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 37 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, approximately 38 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C range, or approximately 39 x 10 -7 / ℃ ~ approx. 40×10 -7 / °C, including all ranges and subranges therebetween.

[0120] Glass is approximately 2.5g / cc 3 ~Approx. 2.6g / cc 3 range, for example, about 2.52 g / cc 3 ~Approx. 2.6g / cc 3 range, approximately 2.54 g / cc 3 ~Approx. 2.6g / cc 3 range, approximately 2.56g / cc 3 ~Approx. 2.6g / cc 3 range, or approximately 2.58 g / cc 3 ~Approx. 2.6g / cc 3 In a particular embodiment, the glass may have a density in the range of about 2.52 g / cc 3 ~Approx. 2.54g / cc 3 The density range can include:

[0121] The glass can have an average transmittance in the range of about 63% to about 80%, e.g., about 63% to about 78%, about 63% to about 76%, about 63% to about 74%, about 63% to about 72%, about 63% to about 70%, about 63% to about 68%, or about 63% to about 66%, including all ranges and subranges therebetween. In further embodiments, the glass can have an average transmittance in the range of about 66% to about 80%, about 68% to about 80%, about 70% to about 80%, about 72% to about 80%, about 74% to about 80%, or about 76% to about 80%, or about 78% to about 80%, including all ranges and subranges therebetween.

[0122] Representative glasses with reduced optical transmittance are shown in Tables 1-5 below. All glass components are listed in mole percent (mol%) on an oxide basis. The glasses were melted and formed into glass sheets 0.7 mm thick. The glasses contain additions of transition metal oxides, specifically NiO and Co3O4, to reduce the optical transmittance of the glass. Optical transmittance was measured with an optical power meter. Figure 6 is a plot of the optical transmittance of glasses S1-S9 from Table 1.

[0123] [Table 1]

[0124] [Table 2]

[0125] [Table 3]

[0126] [Table 4]

[0127] [Table 5]

[0128] The compositions of the glasses listed in Tables 1-5 can be determined using quantitative analytical techniques well known in the art. Suitable techniques include X-ray fluorescence spectroscopy (XRF) for elements with atomic numbers greater than 8, inductively coupled plasma optical emission spectroscopy (ICP-OES), inductively coupled plasma mass spectroscopy (ICP-MS), and electron microprobe analysis. See, for example, J. Nolte, ICP Emission Spectrometry: A Practical Guide, Wiley-VCH (2003); H.E. Taylor, Inductively Coupled Plasma Mass Spectroscopy: Practices and Techniques, Academic Press (2000); and S.J.B. Reed, Electron Microprobe Analysis, Cambridge University Press; 2nd edition (1997), which are incorporated herein by reference.

[0129] The glass properties listed in Tables 1-5 were determined according to techniques customary in the glass industry. Thus, the coefficient of linear thermal expansion (CTE) over the temperature range 0-300°C is 1×10 -7 The anneal point and strain point are expressed in °C. These were determined from the fiber elongation technique (ASTM references E228-85 and C336, respectively). 3 The density at 100°C was measured by the Archimedes method (ASTM C693). The melting temperature (T) in °C (the temperature at which the glass melt exhibits a viscosity of 200 poise) 200P ) was calculated using the Fulcher equation fitted to high temperature viscosity data measured by rotating cylinder viscometry (ASTM C965-81).

[0130] The liquidus temperature of glass in °C was 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 with a gradient temperature zone, heating the boat over the appropriate temperature zone for 24 hours, and determining by microscopy the maximum temperature at which crystals appear within the glass. More specifically, a glass sample is removed from the platinum boat and examined using a polarized light microscope to identify the location and nature of crystals formed within the sample relative to the platinum / air interface. Because the furnace gradient is very well known, the temperature versus location can be adequately estimated to within 5–10 °C. The temperature at which crystals are observed within the sample is considered to represent the liquidus of the glass (for the corresponding test period). Tests may be run for longer periods (e.g., 72 hours) to observe slowly growing phases. The liquidus viscosity in poises was determined from the liquidus temperature and the coefficients of the Fulcher equation.

[0131] Young's modulus values in GPa were determined using a resonant ultrasonic spectroscopy technique of the general type described in ASTM E1875-00e1. Suitable raw materials for making exemplary glasses disclosed herein include commercially available sand as a source of SiO; alumina, aluminum hydroxide, hydrated forms of alumina, and various aluminosilicates, nitrates, and halides as sources of AlO; boric acid, boric anhydride, and boron oxide as sources of BO; periclase, dolomite (also as a source of CaO), magnesia, magnesium carbonate, magnesium hydroxide, and various forms of magnesium silicates, aluminosilicates, nitrates, and halides as sources of MgO; limestone, aragonite, dolomite (also as a source of MgO), wollastonite, and various forms of calcium silicates, aluminosilicates, nitrates, and halides as sources of CaO; and strontium and barium oxides, carbonates, nitrates, and halides. If a chemical fining agent is desired, tin can be added as SnO, as a mixed oxide with other major glass components (e.g., CaSnO), or under oxidizing conditions as SnO, tin oxalate, tin halides, or other tin compounds known to those skilled in the art.

[0132] In addition to elements intentionally incorporated into typical glasses, nearly every stable element in the periodic table is present to some degree in glasses, either through low-level contamination of raw materials, high-temperature erosion of refractories and precious metals during the manufacturing process, or intentional introduction at low levels to fine-tune the properties of the final glass. For example, zirconium may be introduced as a contaminant through interaction with zirconium-rich refractories. As yet another example, platinum and rhodium may be introduced through interaction with precious metals incorporated into the glassmaking equipment. As a further example, iron may be introduced as an impurity in raw materials or intentionally added to enhance gaseous inclusion control. As a further example, manganese may be introduced for color control or to enhance gaseous inclusion control. As a further example, alkalis may be present as impurities at levels up to about 0.1 mol% relative to the combined concentrations of LiO, NaO, and KO.

[0133] Hydrogen forms the hydroxyl anion, OH - , and their presence can be confirmed by standard infrared spectroscopy techniques. Dissolved hydroxyl ions have a large, nonlinear effect on the annealing point of typical glasses, so it may be necessary to adjust the concentration of the major oxide components to compensate for the desired annealing point. Hydroxyl ion concentration can be controlled to some extent by the choice of raw materials or melting system. For example, boric acid is the primary source of hydroxyls, and replacing boric acid with boric oxide can be a useful means to control the hydroxyl concentration of the final glass. The same logic applies to other potential raw materials, including hydroxyl ions, hydrates, or compounds containing physisorbed or chemisorbed water molecules. When using a burner in the melting process, hydroxyl ions can also be introduced through combustion products from the combustion of natural gas and related hydrocarbons, so it may be desirable to transfer the energy used for melting from the burner to the electrodes to compensate. Alternatively, an iterative process of adjusting the major oxide components to compensate for the deleterious effects of dissolved hydroxyl ions can instead be used.

[0134] Sulfur is commonly present in natural gas, as well as being an impurity component in many carbonate, nitrate, halide, and oxide raw materials. In the form of SO2, sulfur can be a troublesome source of gaseous inclusions. The tendency to form SO2-rich defects can be managed to a large extent by controlling the sulfur level in the raw material and incorporating low levels of relatively reduced polyvalent cations into the glass matrix. Without wishing to be bound by theory, it is believed that SO2-rich gaseous inclusions are primarily formed by sulfates (SO4 = The high barium concentration in typical glasses appears to increase sulfur retention in the glass during the early stages of melting, but as mentioned above, barium is used to lower the liquidus temperature and thus increase T 35k -T liqand high liquidus viscosity is obtained. Intentionally controlling the sulfur level in the raw materials to a low level is a useful means for reducing dissolved sulfur (possibly as sulfate) in the glass. In particular, sulfur in the batch materials is preferably less than 200 ppm by weight, and more preferably less than 100 ppm by weight in the batch materials.

[0135] Reduced polyvalent oxides can also be used to control the tendency of typical glasses to form SO2 blisters. Without wishing to be bound by theory, these elements behave as potential electron donors that suppress the electromotive force of sulfate reduction. Sulfate reduction can be written as a half-reaction as follows: SO4 = →SO2+O2+2e - In the formula, e - indicates electrons. The "equilibrium constant" of a half-reaction is K eq =[SO2][O2][e - ] 2 / [SO4 = ] is. where the brackets represent chemical activity. Ideally, the reaction would be forced to produce SO2, O2, and 2e - The addition of nitrates, peroxides, or other oxygen-rich raw materials can be helpful, but they can also work against sulfate reduction in the early stages of melting, offsetting the benefits of adding them initially. SO2 has very low solubility in most glasses, making it impractical to add to the glass melting process. Electrons can be "added" by reducing multivalents, e.g., divalent iron (Fe 2+ The appropriate electron-donating half-reaction for 2Fe 2+ →2Fe 3+ +2e -

[0136] The "activity" of this electron is such that the sulfate reduction reaction proceeds to the left and the SO4 = Suitable reducing polyvalent metals include Fe 2+, Mn 2+ , Sn 2+ , Sb 3+ , As 3+ , V 3+ , Ti 3+ These include, but are not limited to, As, Sb, and others well known to those skilled in the art. In each case, it is important to minimize the concentration of such components to avoid adversely affecting the color of the glass, and in the case of As and Sb, it can be important to avoid adding such components at such high levels that they complicate waste management in the end user's process. In addition to the major oxide components of typical glasses and the minor or impurity components noted above, halides may be present at various levels, either as contaminants incorporated by raw material selection or as components intentionally used to remove gaseous inclusions within the glass. Halides may be incorporated as fining agents at levels of about 0.4 mol% or less, although it is generally desirable to use lower amounts to avoid corrosion of off-gas treatment equipment. In some embodiments, the concentration of individual halide elements is less than about 200 ppm by weight for each individual halide, or less than about 800 ppm by weight for the sum of all halide elements.

[0137] 7 and 8 , a top view and a simplified cross-sectional view, respectively, of another exemplary large-area display 100 are shown. The large-area display 100 includes a base plate 102 and a plurality of small-format displays 104 arranged on the base plate 102. Each small-format display 104 can be a microLED display, such as a top-emitting microLED display or a bottom-emitting microLED display. Between the edges of adjacent small-format displays 104, there is a seam 106. As will be described in more detail below with reference to FIGS. 9-11 , light emitted from the small-format displays 104 can leak from the edges of the small-format displays at the seam 106, resulting in a visible seam when the large-area display 100 is turned on.

[0138] The base plate 102 can be a glass substrate, a printed circuit board, or other suitable substrate that includes circuitry for delivering power and signals to each small format display 104 and for controlling the operation of each micro LED in each small format display 104. The base plate 102 can be attached to the small format displays 104 using, for example, fasteners and / or adhesive materials. In this embodiment, the large area display 100 includes 16 small format displays 104 arranged in four rows and four columns, although in other embodiments, the large area display 100 can include any suitable number of small format displays 104 arranged in any suitable number of rows and columns.

[0139] FIG. 9 is a top view of an exemplary small format display 104. The small format display 104 includes a backplane 202 and a plurality of pixels 204 electrically connected to the backplane 202. Each pixel 204 can include one, two, three, four, or more micro LEDs to provide a monochrome or color display. The backplane 202 can be a glass substrate or a printed circuit board that includes circuitry for sending power and signals to each pixel 204 to control the operation of each micro LED of each pixel 204. The small format display 104 includes four edges 203 from which light emitted by the display pixels can escape. In this embodiment, the small format display 104 includes 23 rows and 13 columns of pixels 204, although in other embodiments, the small format display 104 can include any suitable number of rows and columns of pixels.

[0140] 10 and 11 are simplified cross-sectional views of the exemplary small-format display 104 of FIG. 9. In addition to a backplane 202 and pixels 204, the small-format 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 that is in the optical path, has a defined refractive index, and high transmission, and provides reliable adhesion 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, providing a full-color display. Thus, the small-format display 104 includes multiple micro LEDs electrically connected to the backplane 202. Each micro LED 204a, 204b, 204c is electrically connected to circuitry (not shown) on the backplane 202 to control the operation of each micro LED. In this embodiment, the plurality of micro LEDs are top-emitting micro LEDs, such that a majority of the light emitted by the micro LEDs passes through the top of the small format display 104. In an embodiment, the backplane 202 may include a glass substrate having an array of thin film transistors (TFTs) formed thereon, each TFT electrically connected to a micro LED. In other embodiments, the backplane 202 may include a printed circuit board or other suitable substrate.

[0141] The OCA layer 206 may comprise a phenyl silicone or other suitable material, such as Norland Optical Adhesive 60 (available from Norland Products Inc., Jamesburg, NJ, USA), Dymax OP-60 (Dymax®, available from Torrington, CT, USA), or NTT GA700H (available from NTT Advanced Technology Corporation, Tokyo, Japan). The OCA layer 206 is positioned near (e.g., over) the backplane 202 and the plurality of micro-LEDs (204 a, 204 b, 204 c), such as in direct contact with the top surface 210 of the backplane 202 and in direct contact with and encapsulating the plurality of micro-LEDs. The glass layer 208 can include glass such as aluminosilicate, alkali aluminosilicate, borosilicate, alkali borosilicate, aluminoborosilicate, alkali aluminoborosilicate, soda lime, or other suitable glass (e.g., Gorilla® glass, Ceramic Shield, EAGLE XG® glass). The glass layer 208 is proximate to (e.g., over) the OCA layer 206, such as in direct contact with the top surface 212 of the OCA layer 206. The glass layer 208 can be laminated to the backplane 202 and the plurality of micro LEDs via the OCA layer 206 to protect the micro LEDs and improve the mechanical properties of the small format display 104.

[0142] The OCA layer 206 and glass layer 208 can cause edge light leakage through the edge 203 of the small format display 104 by several different mechanisms. As shown at 216a in FIG. 10 , a first way in which the OCA layer 206 and glass layer 208 can cause edge light leakage through the edge 203 of the small format display 104 involves light leaking out the sidewalls of the micro-LEDs and directly out the edge of the OCA layer 206 and / or glass layer 208. Because the OCA layer 206 has a higher refractive index than air, more light is emitted from the sidewalls of the micro-LEDs in a display including the OCA layer 206 and glass layer 208 compared to a display without the OCA layer 206 and glass layer 208. Thus, the OCA layer 206 and glass layer 208 enhance edge light leakage. As shown at 216a in FIG. 10 , a second way in which the OCA layer 206 and glass layer 208 can cause edge light leakage through the edge 203 of the small format display 104 involves light leaking out the sidewalls of the micro-LEDs, first to the top surface 218 of the glass layer 208, being reflected by the interface between the air and the glass layer 208 (e.g., primarily by total internal reflection (TIR)), and then exiting the edge 203 of the display.

[0143] 11 at 216c, a third way in which the OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 203 of the small format display 104 includes light emitted from the top surface of the micro LEDs directly exiting the edge 203 of the OCA layer 206 and / or the glass layer 208. As shown at 216d in FIG. 11, a fourth way in which the OCA layer 206 and the glass layer 208 can cause edge light leakage through the edge 302 of the small format display 104 includes light being emitted from the top surface of the micro LEDs, first traveling to the top surface 216 of the glass layer 208, being reflected by the interface between the air and the glass layer 208 (e.g., primarily by TIR), and then exiting the edge 203 of the small format display 104.

[0144] Other phenomena that can be mitigated by the use of the reduced transmittance glasses described herein include haloing or blooming, which is particularly noticeable in local dimming displays, such as full-array local dimming LCD displays. Full-array local dimming displays have LEDs positioned behind the entire display panel, and the LEDs are divided into local dimming zones. To create a bright area in one area of the display, the LEDs in the zone behind the bright area are turned on, and the LEDs in the surrounding areas are dimmed or turned off. The halo effect occurs when light from an isolated bright area of the display leaks into the surrounding dark areas, which can result in muddy blacks.

[0145] In much the same way that glass with reduced transmittance can be used to mitigate light leakage in bottom-emission display devices, glass with reduced transmittance can be used to mitigate light leakage from top-emission display devices. That is, when glass is employed as a cover glass plate, light leaking from the light emitter (e.g., from internal reflection and / or edge emission from the light emitter), typically intersecting the glass cover plate at an oblique angle relative to the major surface of the glass cover plate, can reduce the intensity of the leaked light and increase contrast. Light transmitted directly from the light emitter is attenuated less than leaked light because the light travels a shorter distance through the glass than light transmitted obliquely. In embodiments, the cover glass plate can be laminated directly (without an air gap) to the light emitter backplane substrate, for example, via an OCA layer. These phenomena are not limited to tiled displays.

[0146] Accordingly, disclosed herein are displays configured to suppress unwanted light emitted from both self-emissive displays (e.g., microLED displays) and LCD displays. The displays can include an OCA layer 206 and a glass layer 208, and the unwanted light can be mitigated by adjusting the geometric design (e.g., thickness of the glass layer 208 and / or OCA layer 206) and optical properties (e.g., refractive index and transmittance (or absorbance)) of the glass layer 208 and / or OCA layer 206. Optimal designs can be determined by ray tracing modeling, considering edge light leakage suppression performance and luminance at the normal to the display. 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.

[0147] In embodiments, to suppress edge light leakage from the small format display 104, as described further below with reference to Figures 10 and 11, the OCA layer 206 can have a thickness 220 between the top surface 210 of the backplane 202 and the top surface 212 of the OCA layer 206 in a range of about 0.005 millimeters to about 0.2 millimeters, a transmittance (through the OCA layer thickness at about 550 nanometers) in a range of about 40% to about 95 percent, and a refractive index (at about 550 nanometers) in a range of about 1.1 to about 1.6. In other embodiments, the thickness 220 of the OCA layer 206 can be in a range of about 0.01 millimeters to about 0.1 millimeters. In other embodiments, the transmittance of the OCA layer 206 can be in a range of about 50 percent to about 90 percent, e.g., in a range of about 60 percent to about 85 percent, or in a range of about 60 percent to about 80 percent. In other embodiments, the refractive index of the OCA layer 206 can be in a range of about 1.2 to about 1.4.

[0148] In embodiments, the glass layer 208 can have a thickness 222 between the top surface 212 of the OCA layer 206 and the top surface 218 of the glass layer 208 in a range of about 0.05 millimeters to about 2 millimeters, e.g., in a range of about 0.1 millimeters to about 0.3 millimeters. It has been observed that employing a glass cover plate 208 comprising a reduced transmittance glass, such as the reduced transmittance glasses disclosed herein, in a top-emission display can improve the contrast ratio of the display. Accordingly, the glass layer 208 (i.e., the glass cover plate) can have a transmittance (through the thickness of the glass layer at about 550 nanometers) in a range of about 40% to about 95%, e.g., in a range of about 40% to about 90%, in a range of about 50% to about 90%, in a range of about 50% to about 85%, or in a range of about 60% to about 80%. The glass layer 208 can have a refractive index (at about 550 nanometers) in the range of about 1.4 to about 2.0, such as in the range of about 1.5 to about 1.7.

[0149] FIG. 12 is a side view of an exemplary micro LED 300. In certain exemplary embodiments, the micro LED 300 can be used for the micro LEDs 204a, 204b, and / or 204c in each pixel 204, as previously described and illustrated with reference to FIGS. 9-11. The micro LED 300 can include a contact pad 302 (e.g., a metal pad), a lower passivation layer 304, an active layer 306 (e.g., a multiple quantum well (MQT) active layer), and an upper passivation layer 308. The contact pad 302 is electrically connected to the upper surface 210 of the backplane 202. The lower surface of the lower passivation layer 304 contacts the contact pad 302. The upper surface of the passivation layer 304 contacts the lower surface of the active layer 306. The upper surface of the active layer 306 contacts the lower surface of the upper passivation layer 308. Each contact pad 302 may have a height (thickness) 310 of about 1 micrometer and a width 312 of about 10 micrometers. The distance 314 between the contact pads 302 may be about 10 micrometers. The height (thickness) 316 of the lower passivation layer 304 may be about 2.2 micrometers, the height (thickness) 318 of the active layer 306 may be about 0.6 micrometers, and the height 320 of the upper passivation layer 308 may be about 2.2 micrometers, so that the total height 322 of the micro LED 300 may be about 5 micrometers. In other embodiments, the micro LED 300 may have other suitable dimensions.

[0150] 13 is a top view of an exemplary pixel 204 including micro LEDs 204a, 204b, and 204c. Each micro LED 204a, 204b, and 204c includes a length 332 of approximately 30 micrometers and a width 334 of approximately 20 micrometers. The distance 336 between the micro LEDs within the pixel 204 can be approximately 25 micrometers. In other embodiments, the micro LEDs 204a, 204b, and 204c and the pixel 204 can have other suitable dimensions.

[0151] It should be clear that aspects discussed and described herein in relation to tiled displays may also be applied to single display panels, for example, the use of reduced transmittance glass as a glass cover plate to improve contrast may be applicable to non-tiled display devices. [Example]

[0152] Example 1 Poly-Si ring field-effect transistors (FETs) were fabricated on Lotus NXT® glass wafers doped with Ni and Co and on a Ni- and Co-free Lotus NXT® sample as a reference. Three wafers were processed for each condition. The poly-Si ring FET fabrication process 400 is shown in FIG. 14. A Lotus NXT® glass wafer 402 (FIG. 14(a)) was coated with a 100 nm SiO2 layer 404 and a 60 nm a-Si layer 406, which were simultaneously deposited on the glass wafer by P5000 plasma-enhanced chemical vapor deposition (PECVD) without breaking vacuum (FIG. 14(b)). The a-Si film was dehydrogenated under vacuum at 450°C for 1 hour and then annealed at 630°C for 12 hours to crystallize and produce a resulting polysilicon layer 408 on the SiO2 layer 404 (FIG. 14(c)). A 250 nm aluminum (Al) layer was sputter deposited and then patterned by photolithography to fabricate the source electrode 410 and drain electrode 412 (FIG. 14(d)). A 100 nm SiO layer 414 was deposited as a gate insulator, on which a 250 nm Al layer was sputter deposited. The top Al layer was patterned to form the top gate electrode 416, and the source and drain contacts were patterned. Finally, the device was annealed at 450° C. for 1 hour to form the FET 418.

[0153] The ring FET layout is shown from the top in Figure 15. The FET devices had a diameter of 140 μm and a thickness of 700 μm. The FET devices were measured by applying voltages to the drain individually at -30 volts, -20 volts, -10 volts, -5 volts, and -1 volt, grounding the source, and sweeping the gate voltage from 5 volts to -30 volts. 57 FETs were measured on each wafer. A typical transfer curve (drain current as a function of gate voltage) for a ring FET is shown in Figure 16. Transfer curves of ring FETs with different drain voltages were obtained for Lotus NXT® glass containing Ni and Co doping, and for Lotus NXT® (standard) glass without glass doping. Under the same measurement conditions, all wafers showed identical performance. The off-state current (min (Id)) of the FET devices was extracted from the transfer curves and plotted at different drain voltages (Vd), as shown in Figure 17, further confirming the observations from the transfer curves.

[0154] Time-of-flight secondary ion mass spectrometry (TOF-SIMS) was used to characterize the Ni on Lotus NXT® glass with Ni and Co doping (curve 460) and without Ni and Co doping (curve 462) after RingFET TFT fabrication. + and Co + The depth profile of the ion concentration was measured. To reduce the complexity of the thin film stack, the area without the Al electrode was measured by TOF-SIMS. The TOF-SIMS results are shown in Figure 18. Co ions showed good stability within the glass, while Ni ions diffused out of the glass but concentrated in the poly-Si layer after the high-temperature deposition process. In summary, TFTs were deposited on glass substrates containing both nickel and cobalt. Measurements performed on the TFTs found no effect on their performance parameters, indicating that the use of small amounts of Co and Ni to address light leakage is unlikely to affect the performance of devices employing such doped glass.

[0155] Example 2 To model the contrast of an encapsulated top-emitting microLED display, such as the displays shown in FIGS. 7-11, and with particular reference to FIG. 9, some microLEDs in the central region of the display were turned on, while the remaining microLEDs in the display were turned off. FIG. 19 shows a top view of the modeled microLED display, and schematically illustrates the central region pixels (1,1) through (5,5). As shown in FIG. 19, for the 5×5 pixels (1,1) through (5,5) in the central region of the display, the microLEDs of four pixels (2,2), (2,4), (4,2), and (4,4) were turned off, and all other microLEDs in the 5×5 array were turned on. Here, the definition of display contrast is: Display contrast (%) = ((average illuminance of active pixels) / (average illuminance of dark pixels)) x 100 is defined as: In the following modeling, the dark pixels used to calculate the display contrast include pixels (2,2), (2,4), (4,2), and (4,4), and all other active pixels in the central region were used to calculate the display contrast active.

[0156] Table 6 shows the geometric parameters of the encapsulation, as well as the parameters of the glass cover plate and OCA material. Two cases were studied: one case (Case 1) included a device with an OCA layer having a refractive index of 1.49, and the other case (Case 2) included a device with an OCA layer having a refractive index of 1.40. In Case 1, an OCA layer with a refractive index of 1.49 is modeled. Figure 18 is a plot of the display contrast improvement (improvement stated in fold) in percent as a function of the glass cover plate transmission, showing an evaluation of the display's light distribution as viewed normal to the display when the glass cover plate transmission was varied from 100% to 48%. It was observed that as the glass cover plate transmission decreased, the light intensity in dark pixel areas and areas without micro-LEDs decreased.

[0157] [Table 6]

[0158] Figure 20 shows the normalized average illuminance of active and dark pixels as a function of the transmission of the glass cover plate. Figure 21 shows the contrast of the display as a function of the transmission of the glass cover plate. Figure 22 shows the contrast improvement of the display as a function of the transmission of the glass cover plate. The contrast improvement of the display by reducing the transmission of the glass cover plate is Contrast improvement (times) = (display contrast w / cover glass transmission Tg) / (display contrast w / cover glass transmission Tg=100) is defined by

[0159] As shown in Figure 20, as the light transmission of the glass cover plate decreases, the illuminance of both the active and dark pixels decreases. However, as the transmission of the glass cover plate decreases, the rate at which the illuminance of the active pixels decreases is much lower than that of the dark pixels. The illuminance of the active pixels decreases linearly as the transmission of the glass cover plate decreases, while the illuminance of the dark pixels decreases approximately exponentially as the transmission of the glass cover plate decreases. This results in an improvement in display contrast as the transmission of the glass cover plate decreases. As shown in Figure 21, when contrast is expressed as a function of the percent transmission of the cover glass plate, the display contrast increases as the transmission of the glass cover plate decreases, but the improvement begins to saturate when the transmission of the glass cover plate is less than about 60%. As shown in Figure 22, the contrast improvement increases as the transmission of the glass cover plate decreases. Compared to a display using a 100% transmission glass cover plate, display contrast can be improved by more than 25 times when the transmission of the glass cover plate is less than about 80%.

[0160] Next, we modeled Case 2, an OCA with a refractive index of 1.40. Figure 23 shows the normalized average illuminance of the active and dark pixels as a function of the glass cover plate transmission. Figure 24 shows the display contrast as a function of the glass cover plate transmission. Figure 25 shows the display contrast improvement as a function of the glass cover plate transmission. Similar to Case 1, the data indicates that display contrast improvement can be achieved by reducing the glass cover plate transmission. Thus, the analysis indicates that introducing appropriate, e.g., increased light absorption, in the glass cover plate of an encapsulated top-emission microLED display can not only significantly reduce light leakage at the display edges, but also significantly improve the display contrast.

[0161] Example 4 In another experiment, the diffusion of Ni and Co in transition-metal-doped glass substrates was tested in the presence of a barrier layer to determine whether the glass described herein and used as a backplane substrate and / or bottom plate (e.g., to reduce edge light leakage) poses a risk of contaminating TFTs deposited on the backplane substrate. A silicon nitride (commonly referred to as SiNx, where SiNx represents a nitride of silicon, e.g., Si3N4) layer of approximately 100 nm was first deposited by plasma-enhanced chemical vapor deposition (PECVD) on a 5 cm × 5 cm glass substrate (0.7 mm thick) at 400 °C in a furnace, followed by a silica (SiO2) layer of approximately 100 nm, and finally, an amorphous silicon (a-Si) layer was deposited on the silica layer to form the TFT. The glass substrate was Corning® NXT glass doped with sufficient Ni and Co to achieve 70% light transmittance. After the addition of the layers, the glass substrate was cooled to room temperature at a furnace rate, after which the glass substrate was heated in nitrogen (N) at a rate of approximately 5°C per second for 30 minutes to a temperature of 620°C, then cooled at approximately 5°C per second from 620°C to approximately 350°C, after which the cooling rate was reduced. After the glass had cooled to room temperature, measurements of the sample were performed by TOF-SIMS, with measurements taken at various depths in the layered glass substrate. The data is shown in Figure 26, which shows normalized intensity as a function of depth into the coated surface of the glass substrate.

[0162] This experiment was also carried out on a second glass substrate comprising a first layer of silica deposited to a thickness of about 200 nm on the glass substrate and an a-Si layer having a thickness of about 60 nm deposited on the silica layer. The data for this glass substrate is shown in Figure 27, which again shows normalized intensity as a function of depth into the coated surface of the glass substrate.

[0163] 26 and 27 show the symbols for cobalt (Co, circle data points) that is essentially stopped at the glass-SiNx interface. Nickel (Ni, square data points) is more mobile within the glass, resulting in greater strength at the glass-SiNx interface, but without further diffusion into the SiNx boundary layer. FIG. 26 shows the presence of nitrogen (N, asterisk data points) as a result of nitrided silicon. Silicon (Si) is represented by triangle data points. Referring to FIG. 27, a second experiment used a SiO2 barrier layer without a SiNx layer, and deposited a simulated TFT thereon, with results nearly identical to those shown in FIG. 26. That is, FIGS. 26 and 27 show that both SiNx and / or SiO2 are effective barrier layers to prevent contamination of TFTs deposited on Ni- and / or Co-doped glass when positioned between the TFT (or other electronic component, e.g., thin film, component) and the doped glass.

[0164] Example 5 A glass substrate containing Corning® NXT glass doped with sufficient Ni and Co to achieve 70% transmittance was supported on a silicon wafer and separated by 700 μm by silicon spacers. The purpose of the experiment was to determine the extent to which the Co- or Ni-doped glass would release Co or Ni (e.g., by evaporation) to a level that would contaminate the interior of a furnace (e.g., a furnace used for TFT deposition) or other components within the furnace (e.g., display device, TFTs, etc.). The sample was heated to 620°C in a furnace and maintained at 620°C for 30 minutes in nitrogen (N2) at a rate of approximately 5°C per second. The glass substrate was then cooled to room temperature. Upon cooling, the doped glass was removed, and the silicon wafer surface facing the doped glass substrate was analyzed by Time of Flight-SIMS. The data are shown in Figure 28. Circles represent Co, squares represent Ni, and triangles represent Si. Nitrogen is represented by asterisks. The presence of nitrogen is believed to result from furnace contamination and / or nitrogen from the heating environment. Nevertheless, the data show virtually no Co and / or Ni intensity signal beyond the barrier layer, indicating that the Co and / or Ni doped glasses described herein pose no contamination risk when used in the presence of an interface layer under typical TFT deposition conditions.

[0165] 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 present disclosure. Since modifications, combinations, subcombinations, and variations of the disclosed embodiments may occur to those skilled in the art, the present disclosure should be construed as including all within the scope of the appended claims and their equivalents.

Claims

1. In mole percent based on oxides, SiO 2 61-74 and; Al 2 O 3 9~14と; B 2 O 3 0 to 12; MgO 0-9 and; CaO 3.5-12; SrO 0-5 and; BaO 0-5 and; SnO 2 0 to 0.15; NiO 0.025 to 0.13; Co 3 O 4 0.005~0.04と、 A glass article comprising glass having a composition containing, (MgO + CaO + SrO + BaO) / Al 2 O 3 is 1 or more, A glass article having an average light transmittance of less than 90% over a wavelength range of 450 nm to 650 nm at a thickness of 0.7 mm.

2. The glass article according to claim 1, wherein the average light transmittance is in the range of 60% to 82%.

3. The glass article according to claim 1, wherein the light transmittance of the glass article over a wavelength range of 450 nm to 650 nm at a thickness of 0.7 mm is within + / - 5% of the average light transmittance.

4. The aforementioned glass contains B in an amount ranging from approximately 0.2 mol% to approximately 12 mol%. 2 O 3 A glass article according to any one of claims 1 to 3, including the glass article according to any one of claims 1 to 3.

5. The glass article according to claim 1, wherein the glass contains MgO in an amount ranging from 0.9 mol% to 8 mol%.

6. The aforementioned glass, SiO 2 67-74 and; Al 2 O 3 10~14と; B 2 O 3 0 to 3; MgO 3-8 and; CaO 3.9-8; SrO 0-2 and; BaO 2-5 and, A glass article according to claim 1, including the glass article according to claim 1.

7. The aforementioned glass, SiO 2 64-71 and; Al 2 O 3 9~12と; B 2 O 3 7-12 and; MgO 0.9-3; CaO 6-12 and; SrO 0-2 and; BaO 0-1 and A glass article according to claim 1, including the glass article according to claim 1.

8. The aforementioned glass, SiO 2 61-69 and; Al 2 O 3 11~14と; B 2 O 3 5-9 and; MgO 2-9 and; CaO 3-9 and; SrO 1-5 and, A glass article according to claim 1, including the glass article according to claim 1.

9. The aforementioned glass, SiO 2 66-71 and; Al 2 O 3 11~14と; B 2 O 3 3 to 6 and; MgO 3-6 and; CaO 4-7 and; SrO 1-5 and; BaO 0-2 and A glass article according to claim 1, including the glass article according to claim 1.

10. The aforementioned glass, NiO 0.055 to 0.065; Co 3 O 4 0.011~0.013と、 A glass article according to claim 1, including the glass article according to claim 1.

11. The aforementioned glass, NiO 0.077 to 0.128; Co 3 O 4 0.025~0.037と、 The glass according to claim 1, including the glass described in claim 1.

12. The glass article according to claim 1, wherein the liquidus temperature of the glass is in the range of 1000°C to 1300°C.

13. A display device comprising a plurality of display substrates arranged on a bottom plate containing glass as described in claim 1, wherein each display substrate includes a plurality of light-emitting elements disposed thereon and configured to direct light through the bottom plate.

14. Each display substrate has SiO deposited on it between the glass and the plurality of light-emitting elements. 2 The display apparatus according to claim 13, further comprising a barrier layer containing at least one of SiNx.

15. A display substrate including multiple light-emitting elements arranged thereon; An optically transparent adhesive layer is arranged to cover the plurality of light-emitting elements on the display substrate; A glass cover plate is arranged to cover the OCA layer and includes the glass described in claim 1, Display devices, including

16. The display apparatus according to claim 15, wherein the display substrate includes the glass described in claim 1.

17. The display substrate has SiO deposited on it between the glass and the plurality of light-emitting elements. 2 The display apparatus according to claim 15, further comprising a barrier layer containing at least one type of SiNx.

18. The display device according to claim 15, wherein the display device is a top-emission display device, and the plurality of light-emitting elements are configured to direct light through the glass cover plate.

Images