WO2020028237A1 - Curved glass-based articles - Google Patents

Abstract

Glass-based articles are curved, comprising a glass-based substrate having opposing first and second surfaces defining a substrate thickness (t); a first area comprising an alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (t); a second area comprising the alkali metal oxide having a concentration at one or both of the first and second surfaces that is different from the non-zero concentration of the alkali metal oxide present in the first area. The second area may further comprise a block coating that is not ion-exchangeable disposed on the second area of one or both of the first and second surfaces. Methods of making and using the curved glass-based articles are also provided.

Description

CURVED GLASS-BASED ARTICLES

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S.

Provisional Application Serial No. 62/711,829 filed on July 30, 2018, the content of which is relied upon and incorporated herein by reference in its entirety.

FIELD

[0002] Embodiments of the disclosure generally relate to glass-based articles that are curved and methods for manufacturing the same.

BACKGROUND

[0003] Glass-based articles are used in many various industries including consumer electronics, transportation, architecture, defense, medical, and packaging. For consumer electronics, glass-based articles are used in electronic devices as cover plates or windows for portable or mobile electronic communication and entertainment devices, such as mobile phones, smart phones, tablets, video players, information terminal (IT) devices, laptop computers, navigation systems, televisions, and the like. In architecture, glass-based articles are included in windows, shower panels, solar panels, and countertops; and in transportation, glass-based articles are present in automobiles, trains, aircraft, sea craft. Glass-based articles are suitable for any application that requires superior fracture resistance but thin and light weight articles. For each industry, mechanical and/or chemical reliability of the glass-based articles is typically driven by functionality, performance, and cost.

[0004] Chemical treatment is a strengthening method to impart a desired/engineered/improved stress profile having one or more of the following parameters: compressive stress (CS), depth of compression (DOC), and central tension (CT). Many glass-based articles, including those with engineered stress profiles, have a compressive stress that is highest or at a peak at the glass surface and reduces from a peak value moving away from the surface, and there is zero stress at some interior location of the glass article before the stress in the glass article becomes tensile. Chemical strengthening by ion exchange (IOX) of alkali-containing glass is a proven methodology in this field where the focus is primarily symmetric ion exchange of both glass surfaces. [0005] Curved, or 3D-shaped, glasses are promoted for mobile electronics covers, curved TVs, and curved automobile glasses. Standard production processes for 3D glass include: cut and edge finishing, thermal molding at high temperature (600-900°C), surface polishing to remove stains/defects generated at thermal molding process; and chemical treatment, e.g., chemical temper, which can cause further glass shape change and expansion). Such processes add extra steps (forming and finishing) to a typical chemical strengthening of 2D parts, resulting higher cost with lower yield.

[0006] There is an on-going need provide curved or 3D glass-based articles having mechanical and/or chemical reliability for their industry. There is also an ongoing need to do so in cost-effective ways.

SUMMARY

[0007] Aspects of the disclosure pertain to glass-based articles and methods for their manufacture and use.

[0008] In an aspect, a glass-based article comprises: a glass-based substrate having opposing first and second surfaces defining a substrate thickness (t); a first area comprising an alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (t); and a second area comprising the alkali metal oxide having a concentration at one or both of the first and second surfaces that is different from the non-zero concentration of the alkali metal oxide present in the first area, wherein the glass-based article is curved.

[0009] Another aspect provides glass-based article comprising: a glass-based substrate comprising a soda-lime silicate, an alkali-aluminosilicate, an alkali-containing borosilicate, an alkali-containing aluminoborosilicate, or an alkali-containing phosphosilicate and having opposing first and second surfaces defining a substrate thickness (/); a block coating that is not ion-exchangeable on at least a portion of one or both of the first and second surfaces, the block coating comprising an inorganic dielectric material; and a alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (!) in areas where the block coating is absent; wherein a concentration of the alkali metal oxide at the portion of the one or both of the first and second surfaces where the block coating is located is different from the non-zero concentration of the alkali metal oxide in the areas where the block coating is absent, and wherein the glass-based article is curved. [0010] In another aspect, a consumer electronic product comprises: a housing having a front surface, a back surface, and side surfaces; electrical components provided at least partially within the housing, the electrical components including at least a controller, a memory, and a display, the display being provided at or adjacent the front surface of the housing; and a cover disposed over the display; wherein a portion of at least one of the housing and the cover comprises any glass-based article disclosed herein.

[0011] Another aspect is a vehicle that comprises: a body and; an opening in the body; and a structure disposed in the opening, the structure comprising any glass-based article disclosed herein.

[0012] In an aspect, a method of manufacturing a glass-based article comprises: applying a block coating that is not ion-exchangeable to at least a portion of one or both of first and second surfaces of a glass-based substrate to form an at least partially coated glass- based substrate, wherein the first and second surfaces are opposing, defining a substrate thickness (/); exposing the at least partially coated glass-based substrate to a bath comprising alkali metal ions to ion-exchange the glass-based substrate in areas where the block coating is absent and form the glass-based article comprising an alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (!) in areas where the block coating is absent; and a concentration of the alkali metal oxide at the portion of the one or both of the first and second surfaces where the block coating is located is different from the non-zero concentration of the alkali metal oxide in the areas where the block coating is absent; wherein the glass-based article is curved.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The accompanying figures, which are incorporated in and constitute a part of this specification, illustrate several embodiments described below.

[0014] FIG. 1 is a perspective view of an exemplary glass-based substrate prior to application of a block coating or ion exchange;

[0015] FIG. 2 is a side schematic view of an exemplary partially coated substrate prior to IOX, and FIG. 3 is a perspective schematic view of an exemplary resulting curved glass-based article after IOX according to an embodiment;

[0016] FIG. 4 is a side schematic view of an exemplary partially coated substrate prior to IOX, and FIG. 5 is a perspective schematic view of an exemplary resulting curved glass-based article after IOX according to an embodiment; [0017] FIG. 6 is a side schematic view of an exemplary partially coated substrate prior to IOX, and FIG. 7 is a perspective schematic view of an exemplary resulting curved glass-based article after IOX according to an embodiment;

[0018] FIG. 8 is a perspective schematic view of an exemplary curved glass-based article according to an embodiment;

[0019] FIG. 9 is a perspective schematic view of an exemplary curved glass-based article according to an embodiment;

[0020] FIGS. 10-13 are schematic depictions of exemplary block coating patterns and resulting curved glass-article profiles;

[0021] FIG. 14 is a side view of a vehicle incorporating any of the glass-based articles disclosed herein;

[0022] FIG. 15A is a plan view of an exemplary electronic device incorporating any of the glass-based articles disclosed herein;

[0023] FIG. 15B is a perspective view of the exemplary electronic device of FIG. 2 A;

[0024] FIG. 16 is a graph of glass bending distance (mm) versus position along substrate for Examples 1-2, where center of the length of the substrate is at zero;

[0025] FIG.17 is a graph of glass bending distance (mm) versus position along substrate for Examples 3 A-3B, where center of the length of the substrate is at zero;

[0026] FIG.18 is a graph of glass bending distance (mm) versus position along substrate for Examples 4A. 4B, and 4C where center of the length of the substrate is at zero; and

[0027] FIG. 19 is a photograph of the article of Example 5.

DETAILED DESCRIPTION

[0028] Before describing several exemplary embodiments, it is to be understood that the disclosure is not limited to the details of construction or process steps set forth in the following disclosure. The disclosure provided herein is capable of other embodiments and of being practiced or being carried out in various ways.

[0029] Reference throughout this specification to "one embodiment," "certain embodiments," "various embodiments," "one or more embodiments" or "an embodiment" means that a particular feature, structure, material, or characteristic described in connection with the embodiment is included in at least one embodiment of the disclosure. Thus, the appearances of the phrases such as "in one or more embodiments," "in certain embodiments," "in various embodiments," "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

Definitions and Measurement Techniques

[0030] The terms "glass-based article" and "glass-based substrates" are used to include any object made wholly or partly of glass, including glass-ceramics (including an amorphous phase and a crystalline phase). Laminated glass-based articles include laminates of glass and non-glass materials, laminates of glass and crystalline materials. Glass-based substrates according to one or more embodiments can be selected from soda-lime silicate glass, alkali-alumino silicate glass, alkali-containing borosilicate glass, alkali-containing aluminoborosilicate glass, and alkali-containing glass-ceramics.

[0031] A "base composition" is a chemical make-up of a substrate prior to any ion exchange (IOX) treatment. That is, the base composition is undoped by any ions from IOX. A composition at the center of a glass-based article that has been IOX treated is typically the same as the base composition when IOX treatment conditions are such that ions supplied for IOX do not diffuse into the center of the substrate. In one or more embodiments, a composition at the center of the glass article comprises the base composition.

[0032] As used herein a“block coating” is a layer of material that is non-porous or substantially non-porous to alkali metals used for glass ion-exchange. Substantially non- porous means any penetration of alkali metals into the block coating is de minimus and does not result in measureable ion-exchange. In one or more embodiments, block coatings are able to withstand IOX conditions (350-500°C) in that they do not degrade or react in the presence of an IOX bath. Block coatings are different from sol gel coatings in that sol gel coatings are less dense and more porous and less capable of withstanding IOX conditions.

[0033] A glass-based article that is "curved" has one or more surfaces or regions that are non-planar. A curved article has at least one measurable radius of curvature. Curved articles have at least one curved axis associated with a non-planar surface or region.

[0034] As used herein "complex curve" and/or "complexly curved" mean a non- planar shape having simple or compound curves, also referred to as non-developable shapes, which include but are not limited to a spherical surface, an aspherical surface, and a toroidal surface, where the curvature of two orthogonal axes (horizontal and vertical one) are different, which may be for example a toroidal shape, spheroid, and ellipsoid. Complexly curved articles according to embodiments may also include segments or portions of such surfaces, or be comprised of a combination of such curves and surfaces. In one or more embodiments, an article may have a compound curve including a major radius and a cross- curvature. A complexly curved article according to embodiments may have a distinct radius of curvature in two independent directions. According to one or more embodiments, complexly curved articles may thus be characterized as having "cross curvature," where the article is curved along an axis that is parallel to a given dimension and also curved along an axis that is perpendicular to the same dimension. The curvature of the article can be even more complex when a significant minimum radius is combined with a significant cross curvature, and/or depth of bend. Some articles may also include bending along axes of bending that are not perpendicular to the longitudinal axis of the flat glass substrate. As a non-limiting example, an automobile sunroof typically measures about 0.5 m by 1.0 m and has a radius of curvature of 2 to 2.5 m along the minor axis, and a radius of curvature of 4 to 5 m along the major axis.

[0035] Radius of curvature may be measured by any of the following techniques that include multi-position lasers: Tropel® FlatMaster® Surface Form Analysis System by Corning; KLA-Tencor stress/curvature equipment; and stylus surface profilometer.

[0036] It is noted that the terms "substantially" and "about" may be utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. These terms are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue. Thus, for example, a glass-based article that is "substantially free of MgO" is one in which MgO is not actively added or batched into the glass-based article, but may be present in very small amounts as a contaminant.

[0037] Unless otherwise specified, all compositions described herein are expressed in terms of mole percent (mol %) on an oxide basis.

[0038] A“stress profile” is stress with respect to position of a glass-based article. A compressive stress region extends from a first surface to a depth of compression (DOC) of the article, where the article is under compressive stress. A central tension region extends from the DOC to include the region where the article is under tensile stress.

[0039] As used herein, depth of compression (DOC) refers to the depth at which the stress within the glass-based article changes from compressive to tensile stress. At the DOC, the stress crosses from a positive (compressive) stress to a negative (tensile) stress and thus exhibits a stress value of zero. According to the convention normally used in mechanical arts, compression is expressed as a negative (< 0) stress and tension is expressed as a positive (> 0) stress. Throughout this description, however, compressive stress (CS) is expressed as a positive or absolute value - i.e., as recited herein, CS = | CS | . In addition, tensile stress is expressed herein as a negative (< 0) stress. Central tension (CT) refers to tensile stress in a central region or a central tension region of the glass-based article. Maximum central tension (maximum CT or CT_max) occurs in the central tension region nominally at 0.5*t, where t is the article thickness, which allows for variation from exact center of the location of the maximum tensile stress.

[0040] As used herein, the terms "depth of exchange", "depth of layer" (DOL),

"chemical depth of layer", and "depth of chemical layer" may be used interchangeably, describing in general the depth at which ion exchange facilitated by an ion exchange process (IOX) takes place for a particular ion. DOL refers to the depth within a glass-based article (i.e., the distance from a surface of the glass-based article to its interior region) at which an ion of a metal oxide or alkali metal oxide (e.g., the metal ion or alkali metal ion) diffuses into the glass-based article where the concentration of the ion reaches a minimum value, as determined by Glow Discharge - Optical Emission Spectroscopy (GD-OES)). In some embodiments, the DOL is given as the depth of exchange of the slowest-diffusing or largest ion introduced by an ion exchange (IOX) process.

[0041] A non-zero metal oxide concentration that varies from the first surface to a depth of layer (DOL) with respect to the metal oxide or that varies along at least a substantial portion of the article thickness (!) indicates that a stress has been generated in the article as a result of ion exchange. The variation in metal oxide concentration may be referred to herein as a metal oxide concentration gradient. The metal oxide that is non-zero in concentration and varies from the first surface to a DOL or along a portion of the thickness may be described as generating a stress in the glass-based article. The concentration gradient or variation of metal oxides is created by chemically strengthening a glass-based substrate in which a plurality of first metal ions in the glass-based substrate is exchanged with a plurality of second metal ions.

[0042] Unless otherwise specified, CT and CS are expressed herein in megaPascals

(MPa), thickness is express in millimeters and DOC and DOL are expressed in microns (micrometers). [0043] Compressive stress at the surface is measured by surface stress meter (FSM) using commercially available instruments such as the FSM-6000, manufactured by Orihara Industrial Co., Ltd. (Japan). Surface stress measurements rely upon the accurate measurement of the stress optical coefficient (SOC), which is related to the birefringence of the glass. SOC in turn is measured according to Procedure C (Glass Disc Method) described in ASTM standard C770-16, entitled“Standard Test Method for Measurement of Glass Stress-Optical Coefficient,” the contents of which are incorporated herein by reference in their entirety.

[0044] The maximum central tension (CT) values are measured using a scattered light polariscope (SCALP) model number SCALP-04 available from GlasStress Ltd., located in Tallinn, Estonia.

[0045] DOC may be measured by FSM or SCALP depending on the ion exchange treatment. Where the stress in the glass article is generated by exchanging potassium ions into the glass article, FSM is used to measure DOC. Where the stress is generated by exchanging sodium ions into the glass article, SCALP is used to measure DOC. Where the stress in the glass article is generated by exchanging both potassium and sodium ions into the glass, the DOC is measured by SCALP, since it is believed the exchange depth of sodium indicates the DOC and the exchange depth of potassium ions indicates a change in the magnitude of the compressive stress (but not the change in stress from compressive to tensile); the exchange depth (or DOL) of potassium ions in such glass articles is measured by FSM.

[0046] The stress profile is measured using the refracted near-field (RNF) method may also be used to measure attributes of the stress profile. When the RNF method is utilized, the maximum CT value provided by SCALP is utilized. In particular, the stress profile measured by the RNF method is force balanced and calibrated to the maximum CT value provided by a SCALP measurement. The RNF method is described in U.S. Patent No. 8,854,623, entitled“Systems and methods for measuring a profile characteristic of a glass sample”, which is incorporated herein by reference in its entirety. In particular, the RNF method includes placing the glass-based article adjacent to a reference block, generating a polarization-switched light beam that is switched between orthogonal polarizations at a rate of between 1 Hz and 50 Hz, measuring an amount of power in the polarization- switched light beam and generating a polarization- switched reference signal, wherein the measured amounts of power in each of the orthogonal polarizations are within 50% of each other. The method further includes transmitting the polarization-switched light beam through the glass sample and reference block for different depths into the glass sample, then relaying the transmitted polarization-switched light beam to a signal photodetector using a relay optical system, with the signal photodetector generating a polarization- switched detector signal. The method also includes dividing the detector signal by the reference signal to form a normalized detector signal and determining the profile characteristic of the glass sample from the normalized detector signal.

Asymmetric Ion Exchange(IOX) Treatment

[0047] Disclosed herein are glass-based articles that are curved. The curved or 3D shape is the result of asymmetric ion-exchange (IOX), which is designed to impart IOX in some (first) areas of the glass-based substrate and no to minimal IOX in other (second) areas of the glass-based substrate. In this way, due to the varying degrees of IOX in the substrate surface, curvature is imparted to the article in a controlled manner. Asymmetric IOX disclosed herein is achieved by applying a block coating on a second area of one or both of first and second surfaces of a glass-based substrate such that upon IOX, IOX occurs in a first area where the block coating is absent. This results in an asymmetric stress profile and a 3D shape. By intentionally creating an asymmetric ion exchange, chemical strengthening and 3D forming can be fulfilled in one step. By doing so, product yields are significantly improved and manufacture costs are reduced.

[0048] Chemical strengthening by ion exchange (IOX) of alkali-containing glass having a thickness (/), which creates an ion exchange depth of layer (DOL) is typically designed to achieve symmetric ion exchange of both glass surfaces. IOX that is applied in a symmetric manner results in a symmetric stress profile where stress from each surface is balanced and the glass keeps its shape with some dimensional change. Central tension (CT) zone at the center of the glass balances compressive stress (CS) zone at the surfaces. An energy balance model summarizes this relationship:

CTdx where x is the distance away from the surface toward to the center, CS is compression stress profile as a function of x, CT is tension stress profile as a function of x, and t is the thickness of the glass article.

[0049] When IOX is done in an asymmetric manner, an unbalanced strain/stress is introduced into the glass, leading to bending. Depending on design and location of a block coating, a 3D shape formation can be achieved by an asymmetric IOX approach. For a fully one-sided masked square glass as an example, bending is in all the directions uniformly, forming a sphere shape. [0050] The methods disclosed herein are advantageous in that they may be applied to any ion exchangeable glass-ceramics and glass (sodium ion reach ceramics, soda lime glass, Gorilla glasses, and the like). Block coatings can survive up to 500°C without delamination at 400-480°C IOX process. Thicknesses and placement of the block coatings can be controlled at ±lnm by most coating processes, which allows for precise design of percentage of areas that are IOX’d (no block coating) relative to those that are not (block coating present). Forming articles that are curved, including those that are complexly curved can be done with processes that are much less costly as compared to thermal mold forming. Processes are amenable to high throughput coating and batch IOX. The processes herein can form most 3D shapes especially for large curvature. Areas/surfaces of block coating side will have a concave surface after IOX. Though selective and designed deposition of block coatings, complicated 3D shapes can be achieved with one piece of glass. Potential applications include but are not limited to curved automotive interiors, curved TV cover glass, 3D handheld (HH) and information terminal (IT) parts.

[0051] The methods herein include coating processes for application of the block coating and ion exchange processes for strengthening and forming the curved articles.

[0052] With respect to coating processes, any coating equipment that can deliver dielectric materials to form coatings, i.e., transparent coatings, is suitable. Coating processes include but are not limited to: physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), and atomic layer deposition (ALD). PVD techniques may include: sputter technique, ion-assisted-electron beam (IAD- EB), thermal evaporation, ion beam, and/or laser ablation.

[0053] Coating thickness impacts extent of IOX. By mechanism, evaporated or sputter film is generated from atoms and molecule sources (E-beam guns and sputter targets) via their condensation on substrates. The initial deposited materials are in clusters with some mobile abilities depending on substrate temperature. With further deposition of materials, coating morphology changes from islands structure to network, and eventually becomes continuous. Coating thickness and porosity can control IOX efficiency and therefore the bending effect. Depending on coating technology, coating mask may have a thickness in the range of > 0 to 100 nm, 10 to 90 nm, 20 to 80 nm, 30 to 70 nm, 40 to 60 nm, or about 50 nm, and all values and subranges therebetween. Coating density is close or even higher than their bulk counterparts starting at a few nm thickness. PVD thickness can be precisely controlled to ±lnm resolution, while CVD is within a few nm. The coatings may be applied in a single layer or in multiple layers. The multiple layers may have the same or different compositions.

[0054] In one or more embodiments, the block coating is applied directly to one or both of the first and second surfaces of the substrate. In other embodiments, the block coating is applied to one or both of the first and second surfaces of the substrate that already has a coating such as: an anti-reflection coating, a color control coating, and an optical filter coating.

[0055] Regarding refractive index, it is preferred that the block coatings do not interfere with viewing through the glass-based articles and that the refractive index closely matches that of the underlying substrate. In one or more embodiments, a refractive index of the block coating is within ±5% of a refractive index of the glass-based substrate. As an example of index of refraction matching, a coating of S1O2 doped with AI2O3 can have the same or nearly the same index of refraction (index matching) with a glass-based substrate, which would rendering the coating part on the glass surface invisible or nearly invisible.

[0056] For example, a PVD-deposited coating of S1O2 has a higher index of refraction than bulk S1O2 because the coating is highly compressed under ion beam at deposition. Therefore density is as high as its bulk counterpart without any substantial voids. The relationship of coating packing density vs refractive index is: Porosity (P)= volume of solid part of film/total volume of film. Index of the film is: nf=(l-P)nv + P*ns, where ns is the refractive index of solid and nv is the index of the material filling the voids. If packing density =1, nf=ns. For the purposes of this disclosure, nf > ns for all wavelength range of interest, so density will be higher than the bulk counterpart. Porosity of the block coatings disclosed herein is at least 80%, at least 85%, at least 90%, at least 95%, or at least 99%. Porosity may be in the range of 80% to 100%, and all values and subranges therebetween. In a specific embodiment, density of the block coating is in the range of 95% to 99.5% as compared to the bulk density of the material the block coating.

[0057] In some applications, glass-based articles need to have high CS/DOL to achieve hard and impact resistance, which generally requires an IOX process time greater than 4 hours. To generate glass bend at controlled level, we can use thin inorganic coating at one side to partially mask the IOX. Then, it is capable of achieving any degree of 3D shape by incorporating mask pattern and IOX conditions.

[0058] Block coatings used herein are not ion-exchangeable. Any optical transparent

(at VIS: 350-750nm or higher wavelength) inorganic coating material is suitable. The block coatings comprise one or more inorganic dielectric materials. The inorganic dielectric material may be selected from the group consisting of: alkali-free glass, S1O₂, AI₂O₃, T1O₂, A1N, (A1N)_C(A1₂0₃)I-_C, wherein 0.3 < x < 0.37, Si₃N₄, SiON, TiN, Mg0:Al₂0₃, Zr0₂, Nb₂0₅, Ta₂0_5.or mixtures thereof.

[0059] Depending on the technique used, various raw materials and/or precursors may be used to achieve the desired coating composition. As a non-limiting example, when PVD is used, there is a metal target in reactive sputter (example: Si target under O2 plasma to form S1O2, Al target under O2 plasma to form Ab0₃, or under Ck:N2 to form AlON), dielectrics (S1O2, Ah0₃, ...) at ion beam assisted EB deposition. As another non-limiting example, when CVD is used, Si(OEt)₄ (TEOS) may be used as a precursor for SiCh. As another non-limiting example, when ALD is used, Ta(OEt)₅ (penta(ethoxy)tantalum or tantalum ethoxide) may be used as a precursor for Ta20₅.

[0060] With respect to ion exchange processes, they may independently be a thermal- diffusion process or an electro-diffusion process. Non-limiting examples of ion exchange processes in which glass is immersed in multiple ion exchange baths, with washing and/or annealing steps between immersions, are described in ET.S. Pat. No. 8,561,429, by Douglas C. Allan et al, issued on Oct. 22, 2013, entitled "Glass with Compressive Surface for Consumer Applications," in which glass is strengthened by immersion in multiple, successive, ion exchange treatments in salt baths of different concentrations; and ET.S. Pat. No. 8,312,739, by Christopher M. Lee et al, issued on Nov. 20, 2012, and entitled "Dual Stage Ion Exchange for Chemical Strengthening of Glass," in which glass is strengthened by ion exchange in a first bath is diluted with an effluent ion, followed by immersion in a second bath having a smaller concentration of the effluent ion than the first bath. The contents of U.S. Patent Nos. 8,561,429 and 8,312,739 are incorporated herein by reference in their entireties.

[0061] Temperature and IOX time are two process parameters that impact bending radius. The higher the IOX salt bath temperature and the longer the IOX time, the more amount of glass bending. The amount can be calculated and determined experimentally and conditions chosen to achieve desired curved articles.

Glass-Based Substrates

[0062] Examples of glasses that may be used as substrates may include alkali- alumino silicate glass compositions or alkali-containing aluminoborosilicate glass compositions, though other glass compositions are contemplated. Specific examples of glass- based substrates that may be used include but are not limited to soda-lime silicate glass, an alkali-alumino silicate glass, an alkali-containing borosilicate glass, an alkali-alumino borosilicate glass, an alkali-containing lithium alumino silicate glass, or an alkali-containing phosphate glass. The glass-based substrates have base compositions that may be characterized as ion exchangeable. As used herein, "ion exchangeable" means that a substrate comprising the composition is capable of exchanging cations located at or near the surface of the substrate with cations of the same valence that are either larger or smaller in size.

[0063] In one or more embodiments, the glass-based substrate has an alkali metal oxide content of 2 mole % or greater.

[0064] Exemplary base compositions of substrates may comprise but are not limited to: a soda-lime silicate, an alkali-alumino silicate, an alkali-containing borosilicate, an alkali- containing aluminoborosilicate, or an alkali-containing phosphosilicate. Glass-based substrates may include a lithium-containing aluminosilicate.

[0065] FIG. 1 is a perspective view of an exemplary glass-based substrate 10 prior to application of a block coating or ion exchange. The substrate 10 is shown“B”-side up. There is an“A”-side opposite the“B”-side, which is not visible in FIG. 1. Usually“A”-side is considered the customer view side of any final product or article. The substrate has a length“1”, a width“w”, and a thickness“t”. The glass-based substrate is considered“2D”. The glass-based substrate has not been exposed to ion exchange conditions and does not have detectable curvature associated with it.

General Overview of Properties of Glass-Based Articles

[0066] The glass-based articles herein are curved in light of asymmetric ion exchange

(IOX). Patterning of block coatings impacts the resulting shape of the article, along with IOX conditions and coating thickness.

[0067] In the glass-based articles, there is a first area comprising an alkali metal oxide having a non-zero concentration that varies from one or both of first and second surfaces to a depth of layer (DOL) with respect to the metal oxide. A stress profile is generated due to the non-zero concentration of the metal oxide(s) that varies from the first surface. The non-zero concentration may vary along a portion of the article thickness. In some embodiments, the concentration of the alkali metal oxide is non-zero and varies, both along a thickness range from about 0·/ to about 0.3·/. In some embodiments, the concentration of the alkali metal oxide is non-zero and varies along a thickness range from about 0·/ to about 0.35·/, from about 0·/ to about 0.4·/, from about 0·/ to about 0.45·/, from about 0·/ to about 0.48·/, or from about 0·/ to about 0.50·/. The variation in concentration may be continuous along the above- referenced thickness ranges. Variation in concentration may include a change in metal oxide concentration of about at least about 0.2 mol% along a thickness segment of about 100 micrometers. The change in metal oxide concentration may be at least about 0.3 mol%, at least about 0.4 mol%, or at least about 0.5 mol% along a thickness segment of about 100 micrometers. This change may be measured by known methods in the art including microprobe.

[0068] In some embodiments, the variation in concentration may be continuous along thickness segments in the range from about 10 micrometers to about 30 micrometers. In some embodiments, the concentration of the alkali metal oxide decreases from the first surface to a point between the first surface and the second surface and increases from the point to the second surface.

[0069] The concentration of alkali metal oxide may include more than one metal oxide (e.g., a combination of Na₂0 and K₂0). In some embodiments, where two metal oxides are utilized and where the radius of the ions differ from one or another, the concentration of ions having a larger radius is greater than the concentration of ions having a smaller radius at shallow depths, while at deeper depths, the concentration of ions having a smaller radius is greater than the concentration of ions having larger radius.

[0070] In one or more embodiments, the alkali metal oxide concentration gradient extends through a substantial portion of the thickness t of the article. In some embodiments, the concentration of the metal oxide may be about 0.5 mol% or greater (e.g., about 1 mol% or greater) along the entire thickness of the first and/or second section, and is greatest at a first surface and/or a second surface 0·/ and decreases substantially constantly to a point between the first and second surfaces. At that point, the concentration of the metal oxide is the least along the entire thickness /; however the concentration is also non-zero at that point. In other words, the non-zero concentration of that particular metal oxide extends along a substantial portion of the thickness t (as described herein) or the entire thickness t. The total concentration of the particular metal oxide in the glass-based article may be in the range from about 1 mol% to about 20 mol%.

[0071] The concentration of the alkali metal oxide may be determined from a baseline amount of the metal oxide in the glass-based substrate ion exchanged to form the glass-based article.

[0072] In a second area of the article, the alkali metal oxide having a concentration at one or both of the first and second surfaces that is different from the non-zero concentration of the alkali metal oxide present in the first area. In the second area, the block coating is present which inhibits ion exchange where it is present.

[0073] Patterning of the block coatings may be done in any design so as to achieve desires shapes and curvatures. Patterning is applied so that the ion exchange is not uniformly applied to the substrate. In this way, asymmetric IOX is achieved. With reference in the following to surface area covered by the block coating, this is the total area covered by the block coating, whether the coating is in one continuous area or is in two or more discrete sections. In one or more embodiments, the block coating in discrete sections may be the same. In one or more embodiments, the block coating is different sections may have one or more different compositions and/or thicknesses.

[0074] The block coating may be applied to the entirety of one side of a substrate. In one or more embodiments, one side of a substrate may be coated over 100% of its surface area, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, 50%, 45%, 40%, 35%, 30%, 25%, 20%, 15%, 10%, 5%, and all values and subranges therebetween.

[0075] Further, the block coating may be applied to both sides of a substrate. In one or more embodiments, with respect to surface area: 50% of one side is covered and 50% of the other side is covered. In one or more embodiments, >0 to <100% of one side is covered, and all values and subranges there between; and >0 to <100% of the other side is covered, and all values and subranges there between.

[0076] FIG. 2 is a side schematic view of an exemplary coated substrate prior to IOX and FIG. 3 is a perspective schematic view of an exemplary resulting curved glass-based article after IOX. Substrate 20 having a front edge 22 receives block coating 26 on one half of its“B”-side surface, which leaves area 24 uncoated. “A”-side surface 28 is entirely uncoated. In FIG. 3, curved glass-based article 21 having the front edge 22 after IOX is shown“B”-side up, where the block coating 26 is located on one half of the“B”-side surface, and the area of no coating 24 on the other half of the“B”-side surface. There is no coating on the entirety of the“A”-side 28 opposite the“B”-side, not shown in FIG. 3. After IOX, there is a concave curve towards the“B”-side in the area of the block coating 26. In the areas of no coating 24 and 28, after IOX, there is an alkali metal oxide having a non-zero concentration that varies from its surface into at least a portion of the thickness (/). In the area of the block coating 26, at the underlying substrate surface, the alkali metal oxide concentration will be different from that in areas 24 and 28. It is expected that that the alkali metal oxide concentration is zero or negligible under the block coating 26. [0077] FIG. 4 is a side schematic view of an exemplary coated substrate prior to IOX and FIG. 5 is a perspective schematic view of an exemplary resulting curved glass-based article after IOX. Substrate 30 having a front edge 32 receives first block coating 36 on one half of its“B”-side surface, which leaves area 34 uncoated. “A”-side surface receives second block coating 37 one half of its surface, which leaves area 38 is uncoated. In FIG. 5, curved glass-based article 31 having the front edge 32 is shown“B”-side up, where the first block coating 36 is located on one half of the“B”-side surface, and the area of no coating 34 on the other half of the B-side surface. In this embodiment, on the“A”-side, there is the second coating 37, which is opposite the area of no coating 34 of the“B”-side. Also, opposite the first block coating 36 on the“B”-side, there is an area of no coating 38. After IOX, there is a concave curve towards the“B”-side in the area of the coating 36, and there is a concave curve towards the“A”-side in the area of the coating 37. In the areas of no coating 34 on the“B”- side and 37 on the“A”-side, after IOX, there is an alkali metal oxide having a non-zero concentration that varies from its surface into at least a portion of the thickness (/). In the area of the block coatings 36 and 37, at the underlying substrate surface, the alkali metal oxide concentration will be different from that in areas 24 and 38. It is expected that that the alkali metal oxide concentration is zero or negligible under the block coatings 36 and 37.

[0078] FIG. 6 is a side schematic view of an exemplary coated substrate prior to IOX and FIG. 7 is a perspective schematic view of an exemplary resulting curved glass-based article after IOX. Substrate 40 having a front edge 42 receives block coating 46 on the entirety of its“B”-side surface. “A”-side surface 48 is entirely uncoated. In FIG. 7, curved glass-based article 41 having the front edge 42 after IOX is shown“A”-side up, where the block coating 46 is located on the“B”-side surface, and the area of no coating 48 on the entirety of the“A”-side opposite the“B”-side. After IOX, there is a concave curve towards the“B”-side in the area of the block coating 66. In the area of no coating 48, after IOX, there is an alkali metal oxide having a non-zero concentration that varies from its surface into at least a portion of the thickness (/). In the area of the block coating 46, at the underlying substrate surface, the alkali metal oxide concentration will be different from that in area 48. It is expected that that the alkali metal oxide concentration is zero or negligible under the block coating 26.

[0079] In FIG. 8, curved glass-based article 51 having front edge 52 after IOX is shown“B”-side up, where the block coating 56 in a series of strips 55a-55e and 55f-55j and a central rectangular section 55k is located on the“B”-side surface, and an area of no coating 58 on the entirety of the“A”-side 58 opposite the“B”-side. Areas of no coating 54a-54e and 54f-54j are shown between the strips. After IOX, there is a concave curve towards the“B”- side in the area of the block coating 56. In the areas of no coating 54a-54j, after IOX, there is an alkali metal oxide having a non-zero concentration that varies from its surface into at least a portion of the thickness (/). In the area of the block coating 56, at the underlying substrate surface, the alkali metal oxide concentration will be different from that in areas 54a-54j and 58. It is expected that that the alkali metal oxide concentration is zero or negligible under the block coating 56.

[0080] In FIG. 9, curved glass-based article 61 having front edge 62 after IOX is shown“B”-side up, where the block coating 66 in a series of strips 65a-65c and 65d-65f and a central rectangular section 65g is located on the“B”-side surface, and an area of no coating 58 on the entirety of the“A”-side 68 opposite the“B”-side. Areas of no coating 64a-64c and 64d-64f are shown between the strips. After IOX, there is a concave curve towards the“B”- side in the area of the block coating 66. In the areas of no coating 64a-64f, after IOX, there is an alkali metal oxide having a non-zero concentration that varies from its surface into at least a portion of the thickness (/). In the area of the block coating 66, at the underlying substrate surface, the alkali metal oxide concentration will be different from that in areas 64a-64f and 68. It is expected that that the alkali metal oxide concentration is zero or negligible under the block coating 66.

[0081] As demonstrated by FIGS. 3, 5, and 7-9, which are non-limiting examples, asymmetric IOX results in a non-uniform strain, which creates a controlled bending and designed shape. No stress is observed in the resulting glass-based articles. Through selective placement of block coating(s) on the substrate surface(s) prior to IOX, non-uniform strain is induced via asymmetric ion exchange, creating a controlled bending and articles having designed shapes. Compressive stress causes the glass material to bend towards the surface having the block coating to keep force balance in the sheet of glass.

[0082] Further possible block coating patterns and resulting post-IOX shapes are shown in FIGS. 10-13. In FIG. 10, there is a central rectangular area of the substrate that receives a block coating in varying circular shapes, and the resulting shape is expected to have straight sides and a bend at the location of the block coating. In FIG. 11, there is a block coating applied in a strip to each of the side edges accompanied by an area of coating deposited in a line of circles separated from the strip, and the resulting shape is expected to have curved side edges. In FIG. 12, a block coating is applied to one third of one surface in circular shapes, and the resulting shape is expected to have curvature in the area of the coating. In FIG. 13, a block coating is applied along the edges in a frame-type pattern, and the resulting shape is expected to have slanted or curved side edges. Without intending to be bound by theory, it is thought that coatings applied in circular shapes would cause a local bending evenly in all the directions from the shape, which could allow for more room/versatile for pattern design and give more capacity for more complicated 3D shapes. Variables would include sizes, distribution, and spacing of the circular shapes. Since stress and strains are continuous, compressive stress would penetrate into coated region of small dots.

[0083] In one or more embodiments, the glass-based articles herein have a surface compressive stress after a final IOX step of: 1000 MPa or greater, 950 MPa or greater, 900 MPa or greater, 850 MPa or greater, 800 MPa or greater, 750 MPa or greater, 700 MPa or greater, 650 MPa or greater, 600 MPa or greater, 550 MPa or greater, 500 MPa or greater, 450 MPa or greater, 400 MPa or greater, 350 MPa or greater, 300 MPa or greater, 250 MPa or greater, 200 MPa or greater, and all values and sub-ranges therebetween.

[0084] In one or more embodiments, the glass-based articles herein have a thickness

(/) in the range of 0.1 mm to 10 mm, 0.2 mm to 9 mm, 0.3 mm to 8 mm, 0.4 mm to 7 mm, 0.5 mm to 6 mm, 0.6 mm to 5 mm, 0.7 mm to 4 mm, 0.8 mm to 3 mm, 0.9 mm to 2 mm, and 1 mm to 1.9 mm, and all values and sub-ranges therebetween.

End Products

[0085] An exemplary article incorporating any of the articles disclosed herein is provided in FIG. 14, showing a vehicle 1600 comprising a body 1610, at least one opening 1620, and a glass-based article 1630, according to one or more embodiments described herein, disposed in the opening. In one or more embodiments, the vehicle may include an interior surface (not shown), and a glass-based article is in an opening of the interior. In one or more embodiment, the glass-based article forms a panel of the interior.

[0086] Another exemplary article incorporating any of the glass-based articles disclosed herein is shown in FIGS. 15A and 15B. Specifically, FIGS. 15A and 15B show a consumer electronic device 200 including a housing 202 having front 204, back 206, and side surfaces 208; electrical components (not shown) that are at least partially inside or entirely within the housing and including at least a controller, a memory, and a display 210 at or adjacent to the front surface of the housing; and a cover substrate 212 at or over the front surface of the housing such that it is over the display. In some embodiments, at least one of a portion of the housing and the cover substrate 212 may include any of the strengthened articles disclosed herein.

Examples

[0087] Various embodiments will be further clarified by the following examples. In the Examples, prior to being strengthened, the Examples are referred to as "substrates". After being subjected to strengthening, the Examples are referred to as "articles" or "glass-based articles".

[0088] In the following examples, block coatings were deposited in an Optorun 2350

PVD coater made by Optorun Co. Ltd. by ion assisted electron beam deposition (IAD-EB). Conditions included a vacuum pressure of >l0 ⁵ Torr and ambient temperature (e.g., 20- 25°C). Block coatings were deposited in various patterns by placing strips of tape on surfaces and/or regions where no coating was to be deposited. After deposition, the tape was removed before ion-exchange treatment.

[0089] Bending radius was measured by a ruler.

[0090] Bending distance was measured by placing the glass article on a flat surface and measuring the largest distance from the flat surface to the top surface of the glass article.

Example 1

[0091] A glass-based article was formed by asymmetric ion-exchange (IOX). A glass substrate, which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate had a composition of: 67.37 mol% S1O2, 3.67 mol% B2O3, 12.73 mol% AI2O3, 13.77 mol% Na₂0, 0.01 mol% K₂0, 2.39 mol% MgO, 0.01 mol% Fe₂0₃, 0.01 mol% Zr0₂, and 0.09 mol% Sn0_2. The glass substrate had the following dimensions: 430.20 millimeters (length) x 145.00 millimeters (width) x 0.55 millimeters (thick).

[0092] A 100 nm coating of Si0₂ was deposited by PVD/IAD-EB onto one half of the

B-side surface of the substrate, that is the coating spanned from the nominal center of the length of the substrate to one edge of one surface, generally in accordance with FIG. 2. There was not a block coating on the other half of the B-side or at all on the A-side. After PVD/IAD-EB, a partially-coated glass substrate was formed.

[0093] The partially coated glass substrate was then exposed to ion exchange treatment having the following conditions: 100% KNO3 at 420°C for 16 hours to form the glass-based article, whose shape was generally in accordance with FIG. 3.

[0094] The resulting glass article displayed bending towards the coated area. [0095] FIG. 16 is a graph of bending distance (mm) versus position along the substrate length, where center of the length of the substrate is at zero.

Example 2

[0096] A glass-based article was formed by asymmetric ion-exchange (IOX). A glass substrate, which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate was the same as that used in Example 1.

[0097] A 80 nm coating of S1O2 was deposited by PVD/IAD-EB generally in accordance with FIG. 4. The block coating was deposited onto one half of the B-side surface of the substrate, such that the coating spanned from the nominal center of the length of the substrate to a first edge of a first surface. There was not a block coating on the other half of the B-side. A 60 nm coating of SiCk was deposited by PVD/IAD-EB onto one half of the A- side, such that the coating spanned from the nominal center of the length of the substrate to a second edge of a second surface. There was not a block coating on the other half of the A- side. After PVD/IAD-EB, a partially-coated glass substrate was formed.

[0098] The partially coated glass substrate was then exposed to the same ion exchange treatment as in Example 1 (100% KN0₃ at 420°C for 16 hours to form the glass- based article). The resulting shape was generally in accordance with FIG. 5.

[0099] The resulting glass article displayed bending in two directions towards the coated areas.

[00100] FIG. 16 is a graph of bending distance (mm) versus position along the substrate length, where center of the length of the substrate is at zero.

Examples 3-A and 3B

[00101] Glass-based articles were formed by asymmetric ion-exchange (IOX). Each glass substrate, which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate had a composition of: 63.60 mol% S1O2 ,15.67 mol% AI2O3, 10.81 mol% Na₂0, 6.24 mol% LEO, 1.16 mol% ZnO, 0.04 mol% Sn0₂, and 2.48 mol% P2O5. The glass substrate had the following dimensions: 138.8.20 millimeters (length) x 69.4 millimeters (width) x 0.55 millimeters (thick).

[00102] Example 3-A received a 20 nm coating of S1O2 and Example 3-B received a 100 nm coating of S1O2, each of which was deposited by PVD/IAD-EB onto the entirety of a B-side surface of the respective substrate generally in accordance with FIG. 6. There was not a block coating at all on the A-side of the respective substrate. After PVD/IAD-EB, partially- coated glass substrates were formed.

[00103] Each partially coated glass substrate was then exposed to ion exchange treatment having the following conditions: 100% KN0₃ at 420°C for 16 hours to form the glass-based articles, whose shapes were generally in accordance with FIG. 7.

[00104] The resulting glass articles displayed bending towards the coated area.

[00105] FIG. 17 is a graph of glass bending distance (mm) versus position along the substrate length, where center of the length of the substrate is at zero. Significant glass curvature was achieved with a 20 nm coating on the B-side. Slightly more curvature was achieved with a 100 nm coating on the B-side.

Examples 4-A, 4-B, 4-C

[00106] Glass-based articles were formed by asymmetric ion-exchange (IOX). Each glass substrate, which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrates were the same as used in Examples 3-A and 3-B.

[00107] Each substrate received a 20 nm coating of S1O2 that was deposited by

PVD/IAD-EB onto the entirety of a B-side surface of the respective substrate. There was not a block coating at all on the A-side of the respective substrate. After PVD/IAD-EB, partially- coated glass substrates were formed.

[00108] The partially coated glass substrate were then exposed to ion exchange treatments having the following conditions: 100% KNO3 at 420°C for varying hours: 4 hours for Example 4-A, 16 hours for Example 4-B, and 32 hours for Example 4-C, to form the glass-based articles, whose shapes were generally in accordance with FIG. 8.

[00109] The resulting glass articles displayed bending towards the coated area.

[00110] FIG. 18 is a graph of glass bending distance (mm) versus position along the substrate length, where center of the length of the substrate is at zero. IOX timing impacted curvature. At 4 hours IOX, curvature was about 60% of the curvature achieved by 16 or 32 hours. There was not a significant difference in curvature between 16 and 32 hours of IOX.

Example 5

[00111] A glass-based article was formed by asymmetric ion-exchange (IOX). The glass substrate, which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate was the same as used in Examples 3-A and 3-B. [00112] The substrate received a 20 nm coating of S1O2, which was deposited by PVD/IAD-EB onto a B-side surface of the substrate in an edge pattern (“frame”) that is depicted by FIG. 13. The coating extended from each edge of the B-side surface for about 10 mm towards the center. There was not a block coating at all on the A-side of the respective substrate or in a central area of the B-side beyond the 10 mm wide“frame”. After PVD/IAD- EB, a partially-coated glass substrate was formed.

[00113] The partially coated glass substrate was then exposed to an ion exchange treatment having the following conditions: 100% KN0₃ at 420°C for 32 hours to form the glass-based articles, whose post-IOX shape was generally in accordance with FIG. 13.

[00114] The resulting glass articles displayed slight edge bending towards the coated area and slight bending in the overall length direction. FIG. 19 is a photograph of the resulting article, whose curvature along its length is shown relative to a straight-edge ruler.

Example 6

[00115] A glass-based article was formed by asymmetric ion-exchange (IOX). A glass substrate which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate had the same composition as the substrate in Example 1. The glass substrate had the following dimensions: 130 millimeters (length) x 65 millimeters (width) x 0.5 millimeters (thick).

[00116] A block coating of S1O2 was deposited in a plurality of discrete sections, arranged in a pattern generally in accordance with FIG. 8. The block coating thickness was 100 nanometers. The block coating was deposited in 10 discrete rectangular sections and a central rectangular section. Each of the 10 sections was 5 millimeters along the length of the substrate and along entirety of the width of the substrate with a spacing of 5 mm. The areas of no coating were 10 discrete rectangular sections of the B-side (65 mm x 5 mm) and the entirety of the A-side. From each end of the substrate, each of which can be referred to as location 0 millimeters, there were 5 sections deposited, starting at 0 millimeters, 10 millimeters, 20 millimeters, 30 millimeters, 40 millimeters. The central rectangular section was nominally 65 mm x 40 mm. After PVD/IAD-EB, a partially-coated glass substrate was formed.

[00117] The partially coated glass substrate was then exposed to ion exchange treatment having the following conditions: 100% KNO3 at 420°C for 120 minutes to form the glass-based article. [00118] The resulting glass article displayed bending in one direction towards the uncoated (A-) side. Bending distance was 3.5 millimeters along the length side at the nominal center of the length.

Example 7

[00119] A glass-based article was formed by asymmetric ion-exchange (IOX). A glass substrate which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate had the same composition as the substrate in Examples 3- A and 3-B. The glass substrate had the following dimensions: 130 millimeters (length) x 65 millimeters (width) x 0.5 millimeters (thick).

[00120] The block coating composition, thickness, application method, and pattern were the same as Example 6.

[00121] The partially coated glass substrate was exposed to ion exchange treatment having the following conditions: 51 wt. % KN0₃ and 49 wt. % NaNCh at 380°C for 88 minutes to form the glass-based article.

[00122] The resulting glass article displayed bending in one direction towards the uncoated (A-) side. Bending distance was 7 millimeters along the length side at the nominal center of the length.

[00123] Bending distance was higher for Example 7 relative to Example 6 for the same coating pattern and differing IOX conditions and underlying substrate.

Example 8

[00124] A glass-based article was formed by asymmetric ion-exchange (IOX). A glass substrate which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate had the same composition and dimensions as the substrate in Example 7.

[00125] A block coating of S1O2 was deposited in a plurality of discrete sections, arranged in a pattern generally in accordance with FIG. 8. The block coating thickness was 100 nanometers. The block coating was deposited in 10 discrete rectangular sections and a central rectangular section. Each of the 10 sections was 5 millimeters along the length of the substrate and along entirety of the width of the substrate with a spacing of 5 mm. The areas of no coating were 10 discrete rectangular sections of the B-side (65 mm x 5 mm) and the entirety of the A-side. From each end of the substrate, each of which can be referred to as location 0 millimeters, there were 5 sections deposited, starting at 0 millimeters, 10 millimeters, 20 millimeters, 30 millimeters, 40 millimeters. The central rectangular section was nominally 65 mm x 40 mm. After PVD/IAD-EB, a partially-coated glass substrate was formed.

[00126] The partially coated glass substrate was then exposed to ion exchange treatment having the following conditions: 51 wt. % KN0₃ and 49 wt. % NaNCh at 380°C for 88 minutes to form the glass-based article.

[00127] The resulting glass article displayed bending in one direction towards the uncoated (A-) side. Bending distance was 5 millimeters along the length side at the nominal center of the length. Glass bending was prominent in center region where the block coating. In the zones of strips, the shape was relatively straight.

Example 9

[00128] A glass-based article was formed by asymmetric ion-exchange (IOX). A glass substrate which had not been exposed to ion exchange treatment, was placed in the coater. The glass substrate had the same composition and dimensions as the substrate in Example 7.

[00129] A block coating of S1O2 was deposited in a plurality of discrete sections, arranged in a pattern generally in accordance with FIG. 9. The block coating thickness was 100 nanometers. The block coating was deposited in 6 discrete rectangular sections and a central rectangular section. Each of the 6 sections was 10 millimeters along the length of the substrate and along entirety of the width of the substrate with a spacing of 10 mm. The areas of no coating were 6 discrete rectangular sections of the B-side (65 mm x 5 mm) and the entirety of the A-side. From each end of the substrate, each of which can be referred to as location 0 millimeters, there were 3 sections deposited, starting at 0 millimeters, 20 millimeters, and 40 millimeters. The central rectangular section was nominally 65 mm x 30 mm. After PVD/IAD-EB, a partially-coated glass substrate was formed.

[00130] The partially coated glass substrate was then exposed to ion exchange treatment having the following conditions: 51 wt. % KNO3 and 49 wt. % NaNC at 380°C for 88 minutes to form the glass-based article.

[00131] The resulting glass article displayed bending in one direction towards the uncoated (A-) side. Bending distance was 5 millimeters along the length side at the nominal center of the length. Glass bending was prominent in center region where there the block coating. In the zones of strips, the shape was straight. [00132] Bending distance was lower for Example 8 relative to Example 9 for differing coating patterns and the same IOX conditions and underlying substrate.

[00133] While the foregoing is directed to various embodiments, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

What is claimed is:

1. A glass-based article comprising:

a glass-based substrate having opposing first and second surfaces defining a substrate thickness (/);

a first area comprising an alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (/); and

a second area comprising the alkali metal oxide having a concentration at one or both of the first and second surfaces that is different from the non-zero concentration of the alkali metal oxide present in the first area,

wherein the glass-based article is curved.

2. The glass-based article of claim 1, wherein the non-zero concentration of the alkali metal oxide in the first area at the one or both first and second surfaces is greater than the concentration of the alkali metal oxide in the second area at the one or both first and second surfaces.

3. The glass-based article of any preceding claim, wherein the concentration of the alkali metal oxide in the second area at the one or both first and second surfaces is zero.

4. The glass-based article of any preceding claim, wherein the second area further comprises a block coating that is not ion-exchangeable disposed on the second area of one or both of the first and second surfaces.

5. The glass-based article of any preceding claim, wherein the glass-based substrate comprises a soda-lime silicate, an alkali-aluminosilicate, an alkali-containing borosilicate, an alkali-containing aluminoborosilicate, or an alkali-containing phosphosilicate.

6. The glass-based article of any preceding claim, wherein the glass-based substrate is 2D and upon ion-exchange, the glass-based article becomes curved.

7. The glass-based article of any preceding claim, wherein the alkali metal oxide comprises one or more of: lithium, potassium, and sodium.

8. The glass-based article of any preceding claim, wherein the second area comprises a plurality of discrete sections.

9. The glass-based article of claim 8, wherein the plurality of discrete sections is arranged in a pattern.

10. The glass-based article of one of claims 8 to 9, wherein each of the discrete sections is in the shape of a polygon, an oval or circle, or combinations thereof.

11. The glass-based article of one of claims 8 to 10, wherein the discrete sections are substantially uniform in composition, shape, and size.

12. The glass-based article of one of claims 1 to 7, wherein the first area comprises the first surface in its entirety and the second area comprises the second surface in its entirety.

13. The glass-based article of one of claims 4 to 12, wherein the block coating comprises an inorganic dielectric material.

14. The glass-based article of claim 13, wherein the inorganic dielectric material is selected from the group consisting of: alkali-free glass, S1O2, AI2O3, Ti0₂, A1N, (A1N)_C(A1₂0₃)I-_C, wherein 0.3<x<0.37, Si₃N₄, SiON, TiN, Mg0:Al₂0₃, Zr0₂, Nb₂0₅, Ta₂0₅, or mixtures thereof.

15. The glass-based article of one of claims 4 to 14, wherein the block coating comprises two or more layers of the inorganic dielectric material.

16. The glass-based article of one of claims 4 to 14, wherein the block coating has a density of at least 90% as compared to a bulk density of material of the block coating.

17. The glass-based article of claim 16, wherein the density is in the range of 95% to 99.5% as compared to the bulk density of the material the block coating.

18. The glass-based article of one of claims 4 to 17, wherein the block coating has a thickness of at least about 5 nm.

19. The glass-based article of claim 18, wherein the thickness is in the range of about 5 nm to about 200 nm.

20. The glass-based article of one of claims 4 to 19, wherein a first refractive index of the block coating is within ±5% of a second refractive index of the glass-based substrate.

21. The glass-based article of one of claims 4 to 20, wherein the block coating is a physical vapor deposition (PVD) coating, a chemical vapor deposition (CYD) coating, a plasma-enhanced chemical vapor deposition (PECVD) coating, or an atomic layer deposition (ALD) coating.

22. The glass-based article of one of claims 1 to 21 having a radius of curvature in the range of 50 mm to about 1000 mm.

23. The glass-based article of one of claims 1 to 21 that is complexly curved.

24. The glass-based article of any preceding claim having a thickness in the range of about 0.1 mm to about 10 mm.

25. The glass-based article of claim 24 having a thickness in the range of about 0.3 mm to about 1.1 mm.

26. The glass-based article of any preceding claim further comprising one or more of: an anti-reflection coating, a color control coating, and an optical filter coating on one or both of the first and second surfaces.

27. A glass-based article comprising:

a glass-based substrate having opposing first and second surfaces defining a substrate thickness (/);

a block coating that is not ion-exchangeable on at least a portion of one or both of the first and second surfaces, the block coating comprising an inorganic dielectric material; and

a alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (!) in areas where the block coating is absent;

wherein a concentration of the alkali metal oxide at the portion of the one or both of the first and second surfaces where the block coating is located is different from the non-zero concentration of the alkali metal oxide in the areas where the block coating is absent, and

wherein the glass-based article is curved.

28. The glass-based article of claim 27, wherein the inorganic dielectric material is selected from the group consisting of: alkali-free glass, S1O2, AI2O3, Ti0₂, A1N, (A1N)_C(A1₂0₃)I-_C, wherein 0.3<x<0.37, Si₃N₄, SiON, TiN, Mg0:Al₂0₃, Zr0₂, Nb₂0₅, Ta₂0₅, or mixtures thereof.

29. The glass-based article of one of claims 27 to 28, wherein the block coating comprises a plurality of discrete sections.

30. The glass-based article of claim 29, wherein the discrete sections are substantially uniform in composition, shape, and size.

31. The glass-based article of one of claims 27 to 30 further comprising one or more of: an anti-reflection coating, a color control coating, and an optical filter coating on one or both of the first and second surfaces.

32. The glass-based article of one of claims 27 to 31, wherein the block coating is in direct contact with one or both of the first and second surfaces.

33. The glass-based article of claim 32, wherein the one of more of: the anti-reflection coating, the color control coating, and the optical filter coating covers the block coating.

34. A consumer electronic product comprising:

a housing having a front surface, a back surface, and side surfaces;

electrical components provided at least partially within the housing, the electrical components including at least a controller, a memory, and a display, the display being provided at or adjacent the front surface of the housing; and

a cover disposed over the display;

wherein a portion of at least one of the housing and the cover comprises the glass- based article of one of claims 1 to 33.

35. A vehicle comprising:

a body and;

an opening in the body; and

a structure disposed in the opening, the structure comprising the glass-based article of one of claims 1 to 33.

36. A method of manufacturing a glass-based article comprising:

applying a block coating that is not ion-exchangeable to at least a portion of one or both of first and second surfaces of a glass-based substrate to form an at least partially coated glass-based substrate, wherein the first and second surfaces are opposing, defining a substrate thickness (/); exposing the at least partially coated glass-based substrate to a bath comprising alkali metal ions to ion-exchange the glass-based substrate in areas where the block coating is absent and form the glass-based article comprising an alkali metal oxide having a non-zero concentration that varies from one or both of the first and second surfaces into at least a portion of the thickness (!) in areas where the block coating is absent; and a concentration of the alkali metal oxide at the portion of the one or both of the first and second surfaces where the block coating is located is different from the non-zero concentration of the alkali metal oxide in the areas where the block coating is absent;

wherein the glass-based article is curved.

37. The method of claim 36, wherein the block coating is applied to the portion of one or both of the first and second surfaces in a plurality of discrete sections.

38. The method of one of claims 36 to 37, wherein the block coating is applied by physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), atomic layer deposition (ALD), sputter technique, ion- assisted-electron beam (IAD-EB), thermal evaporation, ion beam, or laser ablation.

39. The method of claim 38, wherein the block coating is applied by physical vapor deposition (PVD), chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), or atomic layer deposition (ALD).

40. The method of one of claims 36 to 39, wherein a first refractive index of the block coating is within ±5% of a second refractive index of the glass-based substrate.

41. The method of one of claims 36 to 40, wherein the block coating comprises an inorganic dielectric material.

42. The method of claim 41, wherein the inorganic dielectric material is selected from the group consisting of: sodium-free glass, S1O2, AI2O3, T1O2, A1N, (A1N)_c(Aΐ2q3)i-c, wherein 0.3<x<0.37, S13N4, SiON, TiN, MgO: AI2O3, ZrCk, Nb O , Ta O , or mixtures thereof.

43. The method of one of claims 41 to 42, wherein the block coating comprises two or more layers of the inorganic dielectric material.

44. The method of one of claims 36 to 43 further comprising removing the block coating.

45. The method of claim 44, wherein removing the block coating comprises mechanical polishing or chemical etching.

46. The method of one of claims 36 to 45 further comprising coating onto one or both of the first and second surfaces one or more of: an anti-reflection coating, a color control coating, and an optical filter coating.