Cover glass article

Cover glass products

[0001] Cross Reference to Related Applications

[0002] In this document, please request the priority of the U.S. Petition Serial No. 13/774,238 filed on February 22, 2013 under 35U.SC§120, which requires submission on May 31, 2012 under 35U.SC§119 Priority of the US Provisional Application Serial No. 61/653,476. The content of the above application is the basis of this application and is fully incorporated herein by reference.

[0003] Regulation domain

[0004] The present invention relates to a cover for mobile or handheld electronic devices.

[0005] WS

[0006] The cover of the handheld device must not only perform its function, but also be beautiful. Glass is one of the materials used to make this cover plate. The present invention relates to a shaped glass article that has performance characteristics that make it useful as cover glass.

[0007] Overview

[0008] In one aspect, a cover glass product includes a glass body having a three-dimensional shape, an inner side surface and an outer side surface. The inner surface and the outer surface each have a surface roughness (Ra) of less than 1 nanometer, and do not contain indentations with a diameter greater than 150 microns. In some embodiments, the inner and outer surfaces each have a surface roughness (Ra) of less than 0.7 nanometers. In some embodiments, at least one of the inner side surface and the outer side surface has a surface roughness (Ra) of less than 0.3 nanometers. In some embodiments, the wall thickness of the glass body is 0.3-3 mm. In some embodiments, the change in the wall thickness is less than ±100 microns. In some embodiments, the wall thickness varies within ±10% or less.

[0009] In some embodiments, the glass body further includes less than 10 non-indentation defects that can be observed with the naked eye of a person in an area of 25 mm x 25 mm anywhere on the surface at 1000 lux.

[0010] In some embodiments, the glass body includes a flat portion. In some embodiments, the flatness of the flat portion in the area of 10 mm x 10 mm is better than that of ±150 microns, and in other embodiments, the flat portion has a flatness in the area of 25 mm x 25 mm. The flatness is better than soil 50 microns. In some embodiments, the glass body includes at least one curved portion. In some embodiments, the bending radius of the at least one curved portion is about 1-20 mm. In some embodiments, the at least one curved portion is a spline. The bending angle is the angle that the glass rotates around the bending radius, and the unit is degree. For example, a single 90 on a flat glass plate. The radial bending angle will form two planes at right angles to each other. In some embodiments, the bending angle of the at least one bent portion is greater than zero. To 90. . In some embodiments, the bending angle of the at least one bent portion is greater than 90. .

[0011] Embodiments may also have high optical transmittance. In some embodiments, the optical transmittance of the glass body in the wavelength range of 400-800 nanometers is greater than 85%. In some embodiments, the optical transmittance of the glass body in the wavelength range of 400-800 nanometers is greater than 90%.

[0012] Embodiments may have improved strength or damage resistance. In some embodiments, the compressive stress of the glass body is greater than 300 MPa. In some embodiments, the Mohs hardness of the glass body is greater than 7. In some embodiments, the glass body is toughened, and can be chemically toughened or thermally toughened. In some embodiments, the glass body includes ion-exchanged glass. In some embodiments, the layer depth of the ion-exchanged glass is greater than 15 microns or greater than 25 microns.

[0013] Another aspect includes a cover glass product that includes a three-dimensional shape, an inner side surface, and an outer side surface.

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The glass body, and the cover glass product further includes at least one of the following features: a surface roughness (Ra) of less than 1 nanometer, and no indentation with a diameter greater than 150 microns; a surface roughness of less than 0.7 nanometers ( Ra); surface roughness (Ra) less than 0.3 nanometers; wall thickness of 0.3-3 mm, wherein the change of the wall thickness is less than 100 microns or the change of the wall thickness is less than or equal to ±10%; In an area of 25 mm x 25 mm anywhere on the surface, less than 10 non-indentation defects can be observed with the naked eye at 1000 lux; a flat part, wherein the flat part is in an area of 10 mm x 10 mm The flatness of the flat part is better than soil 150 micrometers or the flatness of the flat part in the area of 25 mm x 25 mm is better than soil 50 micrometers; at least one curved part, wherein the bending radius of the at least one curved part is about 120 mm and/or the at least one curved part is a spline; greater than 85% optical transmittance in the wavelength range of 400-800 nanometers or greater than 90% optical transmittance in the wavelength range of 400-800 nanometers; greater than 300 MPa Compressive stress; Mohs hardness greater than 7; ion-exchanged glass; or ion-exchanged glass with a layer depth greater than 15 microns or greater than 25 microns.

[0014] Embodiments can be used in electronic devices. In some embodiments, the glass body is suitable for covering an electronic device with a flat panel display device. In some embodiments, the electronic device is a phone, a display, a television, a handheld device, or a tablet.

[0015] It should be understood that the foregoing general description and the following detailed description are only examples of the present invention, and are used to provide a general comment or framework for understanding the nature and characteristics of the claimed invention. The included drawings provide a further understanding of the present invention, and the drawings are incorporated in and constitute a part of the present invention. The drawings illustrate various embodiments of the present invention, and together with the description are used to explain the principle and operation of the present invention.

[0016] Brief Description of the Drawings

[0017] The following is a description of each figure in the accompanying drawings. For the sake of clarity and conciseness, the drawings are not necessarily drawn to scale, and certain features and views of the drawings may be displayed in an enlarged scale or in a schematic diagram.

[0018] Figure 1 shows an example cover glass shape.

[001 Edge Figure 2 shows another example cover glass shape.

[0020] FIG. 3A shows the surface roughness profile of the side surface of the 3D glass product in contact with the mold, and R_a = 0.691 nm (average).

[0021] FIG. 3B shows the surface roughness profile of the side surface of the 3D glass product that is not in contact with the mold, and R_a = 0.2731 nm (average).

[0022] FIG. 4 shows the surface roughness profile of a flat fused glass, and R_a = 0.2651 nm (average).

[0023] FIG. 5 is the transmittance curve of the 3D cover glass.

[0024] Detailed description of the invention

[0025] The present invention can be more easily understood with reference to the following detailed description, drawings, embodiments, claims, and the previous and following descriptions. However, before disclosing and describing the compositions, articles, devices, and methods of the present invention, it should be understood that the present invention is not limited to the specific compositions, articles, devices, and methods disclosed, unless otherwise stated, because they can of course be changed. of. It should also be understood that the terminology used herein is only for describing specific aspects and not limiting.

[0026] The following description is provided as an enabling teaching. To this end, those skilled in the art should realize and appreciate that various changes can be made to the various embodiments described herein while still achieving the beneficial results. It is also obvious that part of the beneficial results required by the present invention can be obtained by selecting some features without using other features. Therefore, those skilled in the art will recognize that many changes and modifications to the present invention are possible, and in some cases even desirable, and are part of the present invention. Therefore, the following description is only illustrative and does not

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Should be interpreted as constituting a restriction.

[0027] Materials, compounds, compositions and components are disclosed, which can be used in the disclosed methods and compositions, can be used in conjunction with the disclosed methods and compositions, can be used to prepare the disclosed compositions, or are disclosed The method and composition of the embodiment. These and other materials are disclosed herein, and it should be understood that when combinations, subsets, interactions, groups, etc. of these materials are disclosed without explicitly disclosing each of the different individual and common combinations and permutations of these compounds , Each of them is specifically conceived and described in this article. Therefore, if one type of substitutions A, B, and C are disclosed and a type of substitutions D, E, and F and examples of the combined embodiments A-D are also disclosed, then each can be conceived individually and collectively . Therefore, in this example, each of the following combinations of AE, AF, BD, BE, BF, CD, C-E, and CF is specifically envisaged. It should be considered that the above are all from A, B and C; D, E And F; and the contents of the example combination A-D are disclosed. Likewise, any of the above-mentioned subsets or combinations of these subsets are also specifically conceived and disclosed. Therefore, for example, the subgroups of AE, B-F, and C-E are specifically envisaged, and they should be considered to be disclosed from the contents of A, B, and C; D, E, and F; and the example combination A-D. This concept applies to all aspects of this content, including but not limited to any component of the composition and the preparation of the disclosed composition Methods and steps in the method of use. Therefore, if there are multiple additional steps that can be performed, it should be understood that each of these additional steps can be performed by any particular embodiment or combination of embodiments of the disclosed method, and each such combination can be specifically envisaged and It should be considered public.

[0028] Many terms are mentioned in this and the following claims, which have the meanings described herein.

[0029] "Including", "including" or similar terms mean including but not limited to, that is, including but not exclusive.

[0030] The term "about" modifies terms in all ranges unless otherwise stated. For example, about 1, 2, or 3 is equivalent to about 1, about 2, or about 3, and also includes about 1-3, about 1-2, and about 2-3. The disclosed specific and preferred values and ranges of the compositions, components, ingredients, additives and similar aspects are for illustration only, and they do not exclude other defined values or other values within the defined ranges. The compositions and methods of the present invention include compositions and methods having any value or any combination of values, specific values, more specific values, and preferred values described herein.

[0031] Unless otherwise stated, the indefinite article "a" or "an" and its corresponding definite article "the" as used herein means at least one (one/kind), or one (one/kind) or Many (pieces/species).

[0032] The three-dimensional (3D) cover glass according to an aspect of the present invention may be used to cover an electronic device having a display device. In some embodiments, the display area is flat or planar. The 3D cover glass will protect the display device while allowing viewing and interaction with the display device. The 3D cover glass has a front cover glass part and one or more side cover glass parts, the front cover glass part is used to cover the front side of the electronic device where the display device is located; the one or more side covers The plate glass part is used to surround the peripheral side of the electronic device. The front cover glass portion and the one or more side cover glass portions are adjacent.

[0033] Another aspect includes three-dimensional (3D) cover glass, which is used as a cover plate for at least a part of the back and side portions of the electronic device, which is called a backplate. In some embodiments, the backplate is flat or planar. The backplane can protect the electronic components in the device and/or provide a scratch-resistant or damage-resistant surface. The electronic device may also have a display device on part or the entire back of the device. In this case, the backplane may have a flat surface in this area and may be used as a second cover for the second display area. The back cover glass portion is adjacent to one or more side cover glass portions.

[0034] In some embodiments, the 3D cover glass has at least one flat or planar portion. In some embodiments, this flat or planar portion covers at least a portion of the display area of the electronic device. In some embodiments, in an area of 25 mm x 25 mm, such as using FlatMaster^sTested by X, the flatness of flat 3D cover glass is better than that of soil

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10 micrometers, soil 25 micrometers, soil 50 micrometers, soil 75 micrometers, soil 100 micrometers, soil 125 micrometers, soil 150 micrometers, soil 100 micrometers, soil 200 micrometers, ±250 micrometers, ±300 micrometers, or soil 400 micrometers. In some embodiments, in an area of 200 mm×200 mm, as measured by the FlatMaster* tool, the flatness of the flat 3D cover glass is better than 10 μm, 25 μm, 50 μm, and 75 μm. Soil 100 micrometers, soil 125 micrometers, soil 150 micrometers, soil 100 micrometers, soil 200 micrometers, soil 250 micrometers, soil 300 micrometers, or soil 400 micrometers. In one embodiment, in an area of 25 mm x 25 mm, as measured by the FlatMaster tool, the flatness of the flat front cover glass portion is better than 150 microns. In one embodiment, in an area of 200 mm x 200 mm, as measured by the FlatMaster tool, the flatness of the flat front cover glass portion is better than 150 microns. In one embodiment, in an area of 200 mm x 200 mm, as measured by the FlatMaster® tool, the flatness of the flat front cover glass portion is better than 100 microns. In one embodiment, in an area of 200 mm x 200 mm, as measured by the FlatMaste? tool, the flat front cover glass part The flatness is better than soil 50 microns. In one embodiment, in an area of 25 mm x 25 mm, as measured with the FlatMaster tool, the flatness of the flat front cover glass portion is better than 50 microns. In another embodiment, the front cover glass portion may be curved.

[0035] Another aspect of 3D cover glass is the bend radius or curvature. The 3D cover glass has at least one curved surface, and in some embodiments, may include two or more bends. The bend can be constant, including a fixed radius with a constant center point, or can be variable, such as in the case of a spline structure. In some embodiments, the curve is a compound curve with a varying radius, such as the curve depicted by the Burmester curve. The bending angle and radius can be selected based on the peripheral side geometry of the electronic device. In some embodiments, the bending angle is greater than zero. To 90. . In some embodiments, the bending angle may be greater than 90. . In some embodiments, the bending radius is about greater than or equal to about 1 millimeter. In some embodiments, the bending radius is about 1 mm to about 20 mm, about 1 to about 15 mm, about 1 mm to about 10 mm, about 1 mm to about 5 mm, about 2 mm to about 20 mm, about 2 mm. -About 15 mm, about 2 mm to about 10 mm, about 2 mm to about 5 mm, about 5 to about 15 mm, about 5 mm to about 10 mm, or about 1 mm to about 20 mm. In some embodiments, the bending radius is greater than or equal to about 0.25, 0.5, 0.75, 1.0, 1.25, 1.5, 1.75, 2.0, 2.25, 2.5, 2.75, 3.0, 3.5, 4.0, 4.5, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 15.0, 20.0 mm.

[0036] Non-limiting examples of 3D cover glass are shown in FIGS. 1 and 2. In FIG. 1, the 3D cover glass 100 includes a front cover glass portion 102 and a side cover glass portion 104. The side cover glass portion 104 surrounds the front cover glass portion 102 and has a curve, giving the 3D cover glass 100 a dish shape. In FIG. 2, the 3D cover glass 200 includes a front cover glass portion 202 and side cover glass portions 204, 206_oThe side cover glass portions 204 and 206 are on opposite sides of the front cover glass portion 202. [0037] In some embodiments, the 3D cover glass is made of a 2D glass plate, and a thermal reforming method such as described in the following document is used: US Patent Application Publication No. 2010/0000259 (Ukrainczyk (Ukrainczyk) ), "Method of Making Shaped Glass Articles (Method of Making Shaped Glass Articles) Ό, European Patent Application No. 10306317.8 (Corning Incorporated), method and equipment for bending plate materials into shaped articles (Met hod and Appara tus for Bending a Shee t of Mat erial into a Shaped Article) Ό, U.S. Patent Application No. 13/480172 (Bailey, etc., "Glass Molding System and Related Apparatus and Method )), U.S. Provisional Patent Application No. 61/545,332, and U.S. Provisional Patent Application No. 61/545,329, each of which is incorporated herein by reference. In some embodiments, the 2D glass sheet is made by the fusion method. However, other methods can be used For the preparation of 2D glass plates, for example, the float method or the cart press method can also be used.

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[0038] Another aspect includes the uniformity of the wall thickness of the glass sheet. When bending or processing glass, the thickness of the plate ("wall thickness") may change in the bending area, which can lead to optical distortion and a decrease in glass strength. The method of the present invention uniquely preserves the uniformity of the glass over the entire surface and bending area. The 3D cover glass has a uniform wall thickness, usually in the range of 0.3-3 mm. In some embodiments, the thickness is about 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0 mm. In one embodiment, the total variation of the wall thickness of the cover glass wall is within ±100 microns. In another embodiment, the total change of the wall thickness of the cover glass wall is 10 microns, ± 20 microns, ± 30 microns, ± 40 microns, ± 50 microns, and ± 60 microns of the average wall thickness of the glass plate. Soil 70 micrometers, soil 80 micrometers, soil 90 micrometers, soil 100 micrometers, soil 125 micrometers, soil 150 micrometers, soil 200 micrometers, or within ±250 micrometers. In some embodiments, the total variation of the wall thickness of the cover glass wall is within ±10% of the average wall thickness of the glass plate. In some embodiments, the total variation of the wall thickness of the cover glass wall is within ±3% of the average wall thickness of the glass plate. In some embodiments, the total change in the wall thickness of the cover glass wall is 20%, ±15%, ±10%, ±9%, ±8%, ±7%, ±6 of the average wall thickness of the glass plate %, ±5%, ±4%, ±3%, ±2%, or within 1%.

[0039] The 3D cover glass has an inner side surface and an outer side surface. For illustrative purposes, the inner side surface 210 and the outer side surface 212 are shown in FIG. 2. When the 3D cover glass 200 is placed on an electronic device, the inner surface 210 will be located inside the component, and the outer surface 212 will be located outside the component. FIG. 1 shows the inner surface 106 and the outer surface 108. Each surface is smooth, and this smoothness can be characterized by surface roughness. In some embodiments, the inside surface and the outside surface have different surface roughness. In some embodiments, the average surface roughness (RJ) of each surface of the 3D cover glass is less than 1 nanometer. In another embodiment, the average surface roughness of each surface of the 3D cover glass is less than 0.7 nanometers. In some implementations In the method, the average surface roughness of each surface of the 3D cover glass (RJ is less than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, or 3.0 nanometers. In another embodiment, the average surface roughness (required) of at least one surface of the 3D cover glass is less than 0.3 nanometers. In some embodiments, the average surface roughness (Ra) of at least one surface of the 3D cover glass is less than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4 , 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9 or 3.0 nm. In some embodiments, the average surface roughness (RJ) of at least one surface of the 3D cover glass is from about 0.1 nm to about 3.0 nm, from about 0.1 nm to about 2.0 nm, from about 0.1 nm to about 1.5 nm, about 0.1nm-about 1.Onm, about 0.2nm-about 3.Onm, about 0.2nm-about 2.Onm, about 0.2nm-about 1.5nm, about 0.2nm-about 1. Onm, from about 0.4nm to about 3. Onm, from about 0.4nm to about 2. Onm, from about 0.4nm to about 1.5nm, from about 0.4nm to about 0.7nm, or from about 0.4nm to about 1. Onm .

[0040] The surface roughness of the inner surface and the outer surface may be the same or different. In the latter case, for example, the 3D cover glass is prepared by a mold, and only one side of the surface is in contact with the mold when the 3D cover glass is formed. Generally, the 3D cover glass surface that is in contact with the mold is the outer surface. However, the mold can also be designed so that the surface of the 3D cover glass that is not in contact with the mold is the outer surface.

[0041] FIG. 3A shows the surface roughness profile 300 of the first surface of the 3D cover glass that is in contact with the mold when the 3D cover glass is formed. The average surface roughness of Figure 3A is 0.691 nm. FIG. 3B shows the surface roughness profile 302 of the second surface of the 3D cover glass that is not in contact with the mold. The average surface roughness of Figure 3B is 0.2731 nm. The 3D cover glass having the surface profile shown in FIGS. 3A and 3B is formed by a thermal reforming method.

[0042] For comparison purposes, Table 1 shows the surface roughness of five 3D glass samples made by machining, including peak-to-valley shift (PV), root mean square (rms) and average surface roughness (Required) Contour.

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[0043]

<td>sample#</td><td>PV (nm)</td><td>rms (nm)</td><td>R_a (nm)</td>

<td>1</td><td>5.6</td><td>0.59</td><td>0.47</td>

<td>2</td><td>5.6</td><td>0.76</td><td>0.6</td>

<td>3</td><td>5.7</td><td>0.7</td><td>0.56</td>

<td>4</td><td>6.8</td><td>0.8</td><td>0.65</td>

<td>5</td><td>6.4</td><td>0.7</td><td>0.6</td>

[0044] The average surface roughness (Ra) of these samples was 0.4-0.7 nm. It should be noted that the surface roughness of the first surface of the 3D glass article of FIG. 3A is comparable to the surface roughness obtained by machining. Figure 4 shows the surface roughness of the flat glass formed by the original fusion. The average surface roughness (required) of flat glass is 0.2651. It should be noted that the surface roughness of the second surface of the 3D glass article in FIG. 3B can be compared with the surface roughness of flat glass.

[0045] The surface roughness may vary with the process of manufacturing 2D glass or the 3D forming process, and may also be affected by post-processing, such as polishing. In some embodiments, the 3D cover glass is not post-processed, or has a roughness profile as described above before any post-processing.

[0046] Ideally, the just-formed quality of the 3D cover glass will be as good as the quality of the glass sheet forming the 3D cover glass. For the most economical process, it is expected that this surface quality can be achieved without further reprocessing or polishing of the newly formed surface. As used herein, defects include, but are not limited to: indentations (or dimples-depressions on the glass surface), surface cracks/cracks, blisters, debris, cords, small squares, visible crystals, Laps, bubbles, stones and streaks. In some embodiments, in an area of 25 mm x 25 mm anywhere on the surface, a human can observe an average of less than 50, 40, 30, 20, 10, 5, 4, 3 at 1000 lux with the naked eye. 2 or 1 defect. In some embodiments, in a 25 mm x 25 mm area anywhere on the surface, as measured by an optical microscope, there is an average of less than 50,40, 30, 20, 10, 5, 4, 3, 2 or 1 defect with a maximum size of 150 microns. In some embodiments, there is an average of less than 50, 40, 30, 20, 10, 5, 4 in the 25 mm x 25 mm area of one of the surfaces-the inner surface or the outer surface, as measured by an optical microscope. , 3, 2 or 1 defect with a maximum size of 150 microns. In some embodiments, the maximum size of the defect is 1, 2, 3, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 125, or 150 microns.

[0047] In some embodiments, in an area of 25 mm x 25 mm anywhere on the surface, as measured by an optical microscope, there is an average of less than 50, 40, 30, 20, 10, 5, 4, 3, 2 or An indentation (or dimple) with a diameter greater than 150 microns. In some embodiments, the surface of the 3D cover glass is substantially flawless. The use of "essentially flawless" means that there are no indentations (or dimples) larger than 150 microns in diameter on the surface as measured by optical microscopy techniques. In some embodiments, substantially flawless further includes the absence of other defects that can be observed with the naked eye of a person anywhere on the surface at 1000 lux.

[0048] In one embodiment, the 3D cover glass is transparent, and the optical transmittance is greater than 85% in the wavelength range of 400-800 nanometers. In some embodiments, the 3D cover glass is transparent, and the optical transmittance is greater than 75%, 80%, 85%, 87%, 90%, 93%, or 95% in the wavelength range of 400-800 nanometers. FIG. 5 shows the transmittance curve 500 of an example 3D cover glass. Figure 5 also shows a delta curve 502, which represents the percentage difference in transmittance between the 3D cover glass and the glass formed by 2D fusion.

[0049] The coating can be deposited on the surface of the 3D cover glass to make a part of the 3D cover glass translucent or opaque. The part of the 3D cover glass that is not deposited with the coating may be a light hole on the front cover glass part, which allows viewing and interacting with the display device of the electronic device.

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[0050] Another aspect includes the resistance of the 3D cover glass to damage. Many methods (such as tempering) increase the ability of the glass substrate to withstand impact and stress without being damaged. The 3D cover glass (or the 2D glass plate used to manufacture the 3D cover glass) can be strengthened to obtain a compressive stress greater than 300MPa. In some embodiments, the glass is chemically toughened or thermally toughened. In some embodiments, the glass is chemically tempered. In some embodiments, the glass is ion exchanged. In some embodiments, the 3D cover glass is subjected to ion exchange chemical strengthening treatment to simultaneously obtain a compressive stress greater than 300 MPa and an ion exchange layer depth of at least 25 microns. In some embodiments, the ion exchange layer depth is at least 10, 15, 20, 25, 30, 35, 40, 45, or 50 microns. In some embodiments, the depth of the ion exchange layer is about 10-100 microns. The depth of the ion exchange layer is measured from the surface of the glass toward the inside of the glass. The ion exchange layer is characterized by the presence of excessively large ions in the glass lattice structure.

[0051] In some embodiments, compressive stress can be used to measure the damage resistance of the 3D cover glass. In some embodiments, the compressive stress at the glass surface is greater than 300 MPa. In one embodiment, the compressive stress of the cover glass is greater than 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000 MPa or more.

[0052] In some embodiments, the hardness and/or scratch resistance can be used to measure the damage resistance of the 3D cover glass. In one embodiment, the Mohs hardness of the 3D cover glass is greater than 7. In one embodiment, the Mohs hardness of the 3D cover glass is about 6,6.3,6.5,6.7,7.0,7.3,7.5,7.7,8,8.3,8.5,8.7, or 9.

[0053] In one embodiment, the 3D cover glass includes an alkali aluminosilicate glass composition. An exemplary alkali aluminosilicate glass composition comprises: about 60-70 mol% Si0₂ ; About 6T4 mol% A1₂O₃ ; 0 mol% to about 15 mol% B₂O₃; O mol% to about 15 mol% Li20; 0 mol% to about 20 mol% Na₂0; 0 mol% to about 10 mol% &amp; 0; 0 mol% to about 8 mol% Mg0; 0 mol% to about 10 mol% Ca0; 0 mol% to about 5 mol% Zr0₂; 0 mol% to about 1 mol% Sn02; 0 mol% to about 1 mol% Ce02; less than about 50ppm AS2O3; and less than about 50ppm SbzCh; wherein 12 mol% WLi2O+Na2O+K2OW 20 mol% and 0 mol% WMgO+CaOW 10 mol%. (See, for example, U.S. Patent No. 8,158,543, which is incorporated herein by reference in its entirety.)

[0054] Another exemplary alkali aluminosilicate glass composition includes at least about 50 mol% of Alkaline 2 and at least about 11 mol% of Blood 20, and has a compressive stress of at least about 900 MPa. In some embodiments, the glass further contains AI2O3, and at least one of B2O3, K2O, MgO, and ZnO, where -340+27.1·Al₂0₃-28.7 · B2O3+I5.6 · Na₂0-61.4 · K2O+ 8.1 · (Mg0+Zn0) 20 mol%. In a specific embodiment, the glass comprises: about 7-26 mol% of AbOs; 0 to about 9 mol% of B2O3; about 11-25 mol% of NazO; 0 to about 2.5 mol% of ©0; 0 To about 8.5 mol% of MgO; and 0 to about 1.5 mol%. Xuan 0. The glass composition was submitted by MJ Dejneka and others on July 1, 2011 entitled Ion Exchangeable Glass with High Compressive Stress" in the United States. It is described in Provisional Patent Application No. 61/503,734, which is incorporated herein by reference in its entirety.

[0055] In addition to the glass composition as described above, and other types of glass compositions other than the alkali aluminosilicate glass composition can be used for 3D cover glass. For example, an alkaline aluminoborosilicate glass composition can be used for 3D cover glass. In some embodiments, the glass composition used is an ion-exchangeable glass composition, which is generally a glass composition including small alkali metal or alkaline earth metal ions exchangeable with large alkali metal or alkaline earth metal ions. For other examples of ion-exchangeable glass compositions, see US Patent No. 7,666,511 (Ellison et al., November 20, 2008), No. 4,483,700 (Forker Jr. (Forker, Jr.) et al. , November 20, 1984) and U.S. Patent No. 5,674,790 (Araujo; October 7, 1997), and U.S. Patent Application No. 12/277,573 (Dejneka), etc.; November 25, 2008), 12/392,577 (Gomez, etc.; February 25, 2009), 12/856,

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840 (Dejneka, etc.; August 10, 2010), 12/858,490 (Barefoot, etc.; August 18, 2010), and 13/305,271 (Bookbinder, etc.) ; November 28, 2010).

[0056] In some embodiments, as described above, thermal reforming is used to manufacture 3D cover glass from a 2D glass sheet. In some embodiments, the 2D glass sheet is extracted from the original glass sheet formed by the fusion method. The original properties of the glass can be retained until the glass is strengthened, such as ion exchange chemical strengthening.

[0057] Although the present invention has been described with a limited number of embodiments, those skilled in the art benefit from the disclosure of the present invention and will understand that other embodiments can be designed without departing from the scope of the present invention disclosed herein. Therefore, the scope of the present invention should be limited only by the appended claims.

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