Patent Application
20220002192
This application claims the benefit of priority under 35 U.S.C. § 119 of Chinese Patent Application Serial No. 201811397677.8 filed on Nov. 22, 2018 the content of which is relied upon and incorporated herein by reference in its entirety.
The present disclosure relates generally to low-warp, strengthened articles and methods of making these articles; and, more particularly, to asymmetric ion-exchange methods of making strengthened glass, glass-ceramic and ceramic substrates employed in various optical articles.
Protective display covers based on chemically strengthened, ion-exchanged glass substrates are employed in several industries, including consumer electronics (e.g., smartphones, slates, tablets, notebooks, e-readers, etc.), automotive, interior architecture, defense, medical and packaging. Many of these display covers employ Corning® Gorilla Glass® products, which offer superior mechanical properties including damage resistance, scratch resistance and drop performance. As a manufacturing method, chemical strengthening by ion exchange of alkali metal ions in glass, glass-ceramic and ceramic substrates has been employed for many years in the industry to provide these superior mechanical properties. Depending upon the application, a stress profile of compressive stress as a function of depth can be targeted by these ion-exchange methods to provide the targeted mechanical properties.
In a conventional ion-exchange strengthening process, a glass, glass-ceramic or ceramic substrate is brought into contact with a molten chemical salt so that alkali metal ions of a relatively small ionic diameter in the substrate are ion-exchanged with alkali metal ions of a relatively large ionic diameter in the chemical salt. As the relatively larger alkali metal ions are incorporated into the substrate, compressive stress is developed in proximity to the incorporated ions within the substrate, which provides a strengthening effect. As the typical failure mode of the substrates is associated with tensile stresses, the added compressive stress produced by the incorporation of the larger alkali metal ions serves to offset the applied tensile stress, leading to the strengthening effect.
One of the technical challenges associated with these ion-exchange strengthening processes is warpage of the strengthened substrates. In particular, warpage of the substrate can occur during or after the ion-exchange process when the ion-exchange process occurs in an asymmetric fashion between the two primary surfaces of the substrate. Asymmetries of the target substrates with regard to substrate geometries, substrate surfaces, coatings and films on the substrates, diffusivity of alkali metal ions, alkali metal ions in the salt bath and other factors may affect the extent and degree of the observed warpage of the target substrates.
Various approaches to managing warpage are employed in the industry. In general, these approaches tend to add significant cost to the production of glass, glass-ceramic and ceramic substrates employed in display applications and/or result in reduced, or less control over, optical properties. Warpage can cause difficulty in downstream processes associated with producing a display. For example, processes employed to make touch sensor display laminates can be prone to the formation of air bubbles in the laminates owing to the degree of warpage in the substrate. In some instances, additional thermal treatments and/or additional molten salt exposures can be employed to the substrates to counteract warpage associated with ion-exchange strengthening processes. However, these additional process steps result in significantly increased manufacturing costs and/or affect optical properties associated with the substrates. Other approaches, such as post-production grinding and polishing, can also counteract warpage effects, but again at significantly increased production costs.
Accordingly, there is a need for low-warp, strengthened glass, glass-ceramic and ceramic articles and ion-exchange methods for the same, including methods that offer the requisite degree of strengthening, limited cost increases, and significant process control and repeatability, with no effect on the optical properties associated with the articles.
According to an aspect of the present disclosure, a method of making a strengthened article includes: providing an article comprising a glass, glass-ceramic or ceramic composition with a plurality of ion-exchangeable alkali metal ions, a first primary surface and a second primary surface; forming a SiO2-containing film over the first primary surface, wherein the SiO2-containing film comprises a thickness from about 5 nanometers to about 20 nanometers; forming an anti-glare surface integral with the second primary surface; providing a first ion-exchange bath comprising a plurality of ion-exchanging alkali metal ions, each having a larger size than the size of the ion-exchangeable alkali metal ions; and submersing the article in the first ion-exchange bath at a first ion-exchange temperature and duration to form a strengthened article. Further, the strengthened article comprises a compressive stress region extending from the first primary surface and the second primary surface to first and second selected depths, respectively. In some embodiments of this aspect, the step of forming a SiO2-containing film is further conducted such that the first primary surface comprises the SiO2-containing film and the step of forming the SiO2-containing film is conducted after masking the second primary surface; and the step of forming an anti-glare surface is further conducted such that the second primary surface comprises the anti-glare surface and the step of forming the anti-glare surface is conducted after masking the first primary surface with a masking film.
According to some aspects of the present disclosure, a method of making a strengthened article includes: providing an article comprising a glass, glass-ceramic or ceramic composition with a plurality of ion-exchangeable alkali metal ions, a first primary surface and a second primary surface; masking the first primary surface with a first masking film; forming an anti-glare surface integral with the second primary surface after the step of masking the first primary surface; removing the first masking film on the first primary surface after the step of forming an anti-glare surface; masking the anti-glare surface with a second masking film; forming a SiO2-containing film over the first primary surface, wherein the SiO2-containing film comprises a thickness from about 5 nanometers to about 20 nanometers, the step of forming a SiO2-containing film conducted after the step of masking the anti-glare surface; removing the second masking film on the anti-glare surface after the step of forming a SiO2-containing film; providing a first ion-exchange bath comprising a plurality of ion-exchanging alkali metal ions, each having a larger size than the size of the ion-exchangeable alkali metal ions; and submersing the article in the first ion-exchange bath at a first ion-exchange temperature and duration to form a strengthened article, the submersing conducted after the step of removing the second masking film. Further, the strengthened article comprises a compressive stress region extending from the first primary surface and the second primary surface to first and second selected depths, respectively.
According to some aspects of the disclosure, a strengthened glass article is provided that includes: a glass substrate comprising a first primary surface and a second primary surface, and a compressive stress region extending from the first and second primary surfaces to respective first and second selected depths. The second primary surface of the substrate comprises an integrally-formed anti-glare surface. In addition, the glass article comprises a change in warp (Δ warp) of 200 microns or less. The first primary surface comprises a SiO2-containing film having a thickness from about 5 nanometers to about 20 nanometers. Further, the change in warp is measured before and after formation of the compressive stress region.
Additional features and advantages will be set forth in the detailed description which follows, and will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.
The accompanying drawings are included to provide a further understanding of the various embodiments, and are incorporated into and constitute a part of this specification. The drawings illustrate the various embodiments described herein, and together with the description serve to explain the principles and operation of the claimed subject matter.
The following is a description of the figures in the accompanying drawings. The figures are not necessarily to scale, and certain features and certain views of the figures may be shown exaggerated in scale or in schematic in the interest of clarity and conciseness.
In the drawings:
The foregoing summary, as well as the following detailed description of certain inventive techniques, will be better understood when read in conjunction with the figures. It should be understood that the claims are not limited to the arrangements and instrumentality shown in the figures. Furthermore, the appearance shown in the figures is one of many ornamental appearances that can be employed to achieve the stated functions of the apparatus.
Additional features and advantages will be set forth in the detailed description which follows and will be apparent to those skilled in the art from the description, or recognized by practicing the embodiments as described in the following description, together with the claims and appended drawings.
As used herein, the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
In this document, relational terms, such as first and second, top and bottom, and the like, are used solely to distinguish one entity or action from another entity or action, without necessarily requiring or implying any actual such relationship or order between such entities or actions.
Modifications of the disclosure will occur to those skilled in the art and to those who make or use the disclosure. Therefore, it is understood that the embodiments shown in the drawings and described above are merely for illustrative purposes and not intended to limit the scope of the disclosure, which is defined by the following claims, as interpreted according to the principles of patent law, including the doctrine of equivalents.
For purposes of this disclosure, the term “coupled” (in all of its forms: couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature, or may be removable or releasable in nature, unless otherwise stated.
As used herein, the term “about” means that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art. When the term “about” is used in describing a value or an end-point of a range, the disclosure should be understood to include the specific value or end-point referred to. Whether or not a numerical value or end-point of a range in the specification recites “about,” the numerical value or end-point of a range is intended to include two embodiments: one modified by “about,” and one not modified by “about.” It will be further understood that the end-points of each of the ranges are significant both in relation to the other end-point, and independently of the other end-point.
The terms “substantial,” “substantially,” and variations thereof as used herein are intended to note that a described feature is equal or approximately equal to a value or description. For example, a “substantially planar” surface is intended to denote a surface that is planar or approximately planar. Moreover, “substantially” is intended to denote that two values are equal or approximately equal. In some embodiments, “substantially” may denote values within about 10% of each other, such as within about 5% of each other, or within about 2% of each other.
Directional terms as used herein—for example up, down, right, left, front, back, top, bottom—are made only with reference to the figures as drawn and are not intended to imply absolute orientation.
As used herein the terms “the,” “a,” or “an,” mean “at least one,” and should not be limited to “only one” unless explicitly indicated to the contrary. Thus, for example, reference to “a component” includes embodiments having two or more such components unless the context clearly indicates otherwise.
As used herein, “compressive stress” (CS) and “depth of compressive stress layer” (DOL) are measured using means known in the art. For example, CS and DOL are measured by a surface stress meter 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 a modified version of Procedure C described in ASTM standard C770-98 (2013), entitled “Standard Test Method for Measurement of Glass Stress-Optical Coefficient,” the contents of which are incorporated herein by reference in their entirety. The modification includes using a glass disc as the specimen with a thickness of 5 to 10 mm and a diameter of 12.7 mm. Further, the glass disc is isotropic, homogeneous and core-drilled with both faces polished and parallel. The modification also includes calculating the maximum force, Fmax, to be applied. The maximum force (Fmax) is the force sufficient to produce 20 MPa compressive stress. The maximum force to be applied, Fmax, is calculated as follows according to Equation (1):
F
max=7.854*D*h (1)
where Fmax is the maximum force in Newtons, D is the diameter of the glass disc, and h is the thickness of the light path. For each force applied, the stress is computed according to Equation (2):
where Fmax is the maximum force in Newtons obtained from Equation (1), D is the diameter of the glass disc in mm, h is the thickness of the light path in mm, and σ is the stress in MPa.
As used herein, the “depth of compressive stress layer (DOL)” refers to a depth location within the strengthened article where the compressive stress generated from the strengthening process reaches zero.
As also used herein, “anti-glare”, “AG”, or like terms refer to a physical transformation of light contacting the treated surface of an article, such as a display, of the disclosure that changes, or to the property of changing light reflected from the surface of an article, into a diffuse reflection rather than a specular reflection. In embodiments, the AG surface treatment can be produced by chemical etching. Anti-glare does not reduce the amount of light reflected from the surface, but only changes the characteristics of the reflected light. An image reflected by an anti-glare surface has no sharp boundaries. In contrast to an anti-glare surface, an anti-reflective surface is typically a thin-film coating that reduces the reflection of light from a surface via the use of refractive-index variation and, in some instances, destructive interference techniques.
As further used herein, the terms “haze”, “transmission haze” or like terms refer to a particular surface light scatter characteristic related to surface roughness. More particularly, these “haze” terms refer to the percentage of transmitted light scattered outside an angular cone of ±4.0° according to ASTM D1003. For an optically smooth surface, transmission haze is generally close to zero. Transmission haze of a glass sheet roughened on two sides (Haze2-side) can be related to the transmission haze of a glass sheet having an equivalent surface that is roughened on only one side (Haze1-side), according to the approximation of equation (3):
Haze2-side≈[(1−Haze1-side)·Haze1-side]+Haze1-side (3)
Further, haze values are usually reported in terms of percent haze. The value of Haze2-side from eq. (3) must be multiplied by 100.
As also used herein, the terms “gloss”, “gloss level,” or like terms refer to, for example, surface luster, brightness, or shine, and more particularly to the measurement of specular reflectance calibrated to a standard (such as, for example, a certified black glass standard) in accordance with ASTM procedure D523. Common gloss measurements are typically performed at incident light angles of 20°, 60°, and 85°, with the most commonly used gloss measurement being performed at 60°. Due to the wide acceptance angle of this measurement, however, common gloss often cannot distinguish between surfaces having high and low distinctness-of-reflected-image (DOI) values.
Referring to the drawings in general and to
Described in this disclosure are strengthened articles, and methods of making them, that include substrates having a glass, glass-ceramic or ceramic composition and compressive stress regions. Further, these strengthened articles are optimized to exhibit little to no warpage as a result of the methods of the disclosure, despite having an anti-glare surface on one primary surface that would otherwise make them prone to warpage from asymmetric and/or non-uniform ion-exchange effects. In general, the methods of the disclosure control the kinetics of the ion-exchange process to offset any asymmetric or non-uniform ion-exchange conditions that are present in the substrates from the presence of the anti-glare surface, film, or other comparable optical structure. The methods effect this control through adjustment of the surface morphology of the primary surface of the substrate opposite to the primary surface that comprise the anti-glare surface. This adjustment to the surface morphology of the primary surface opposite to the anti-glare surface can be effected through the formation of a SiO2-containing film over this primary surface to increase the uptake of ion-exchanging ions during the strengthening process to offset the increase in the uptake of the same ion-exchanging ions associated with the presence of the anti-glare surface.
The methods of making strengthened articles of the disclosure, along with the strengthened articles themselves, possess several benefits and advantages over conventional approaches to manufacturing strengthened articles comprising glass, glass-ceramic and ceramic compositions. One advantage is that the methods of the disclosure are capable of reducing the degree of warp that would otherwise be induced by non-uniform ion-exchange conditions present in the substrates associated with the presence of an anti-glare surface. Another advantage is that the methods of the disclosure reduce or eliminate warpage in a particularly repeatable fashion, without the need for additional processing steps, e.g., polishing, cutting, grinding, thermal treatments after ion exchange processing, etc. A further advantage of these methods is that they offer little to no increased capital and/or reductions in throughput relative to conventional ion-exchange processing. In particular, the additional fixtures associated with implementing the methods of the disclosure are limited in terms of size and cost (e.g., fixtures and baths for liquid phase deposition of SiO2-containing films, and fixtures for masking surfaces of the substrates).
Another advantage of the methods of making strengthened articles of the disclosure is that they produce compressive stress regions with the same or substantially similar residual stress profiles as compared to conventional ion exchange profiles, while offering the advantage of significantly reduced warpage levels in the strengthened articles produced according to the process. A further advantage of these methods is that they allow for the development of an anti-glare surface in the substrate prior to the development of a compressive stress region through an ion-exchange strengthening process, thus ensuring that the development of the anti-glare surface does not inhibit or reduce the magnitude of the compressive stresses during the strengthening process. Put another way, the development of an anti-glare surface, such as outlined in the disclosure, can, according to embodiments, reduce the thickness of the substrate by an order of magnitude that can reduce or eliminate the compressive stress region in a substrate that has been subjected to an ion-exchange strengthening process prior to development of the anti-glare surface.
Referring to
With further regard to the strengthened glass article 100 depicted in
Referring again to the strengthened glass article 100 shown in
Referring again to
The substrates 10 employed in the strengthened glass articles 100 can comprise various glass compositions, glass-ceramic compositions and ceramic compositions. The choice of glass is not limited to a particular glass composition. For example, the composition chosen can be any of a wide range of silicate, borosilicate, aluminosilicate, or boroaluminosilicate glass compositions, which optionally can comprise one or more alkali and/or alkaline earth modifiers.
By way of illustration, one family of compositions that may be employed in the substrates 10 includes those having at least one of aluminum oxide or boron oxide and at least one of an alkali metal oxide or an alkaline earth metal oxide, wherein—15 mol %≤(R2O+R′O−Al2O3−ZrO2)−B2O3≤4 mol %, where R can be Li, Na, K, Rb, and/or Cs, and R′ can be Mg, Ca, Sr, and/or Ba. One subset of this family of compositions includes from about 62 mol % to about 70 mol % SiO2; from 0 mol % to about 18 mol % Al2O3; from 0 mol % to about 10 mol % B2O3; from 0 mol % to about 15 mol % Li2O; from 0 mol % to about 20 mol % Na2O; from 0 mol % to about 18 mol % K2O; from 0 mol % to about 17 mol % MgO; from 0 mol % to about 18 mol % CaO; and from 0 mol % to about 5 mol % ZrO2. Such glasses are described more fully in U.S. Pat. Nos. 8,969,226 and 8,652,978, hereby incorporated by reference in their entirety as if fully set forth below.
Another illustrative family of compositions that may be employed in the substrates 10 includes those having at least 50 mol % SiO2 and at least one modifier selected from the group consisting of alkali metal oxides and alkaline earth metal oxides, wherein [(Al2O3 (mol %)+B2O3(mol %))/(Σ alkali metal modifiers (mol %))]>1. One subset of this family includes from 50 mol % to about 72 mol % SiO2; from about 9 mol % to about 17 mol % Al2O3; from about 2 mol % to about 12 mol % B2O3; from about 8 mol % to about 16 mol % Na2O; and from 0 mol % to about 4 mol % K2O. Such glasses are described more fully in U.S. Pat. No. 8,586,492, hereby incorporated by reference in its entirety as if fully set forth below.
Yet another illustrative family of compositions that may be employed in the substrates 10 includes those having Sift, Al2O3, P2O5, and at least one alkali metal oxide (R2O), wherein 0.75≤[(P2O5(mol %)+R2O (mol %))/M2O3 (mol %)]≤1.2, where M2O3=A12O3+B2O3. One subset of this family of compositions includes from about 40 mol % to about 70 mol % SiO2; from 0 mol % to about 28 mol % B2O3; from 0 mol % to about 28 mol % Al2O3; from about 1 mol % to about 14 mol % P2O5; and from about 12 mol % to about 16 mol % R2O. Another subset of this family of compositions includes from about 40 to about 64 mol % SiO2; from 0 mol % to about 8 mol % B2O3; from about 16 mol % to about 28 mol % Al2O3; from about 2 mol % to about 12 mol % P2O5; and from about 12 mol % to about 16 mol % R2O. Such glasses are described more fully in U.S. patent application Ser. No. 13/305,271, hereby incorporated by reference in its entirety as if fully set forth below.
Yet another illustrative family of compositions that can be employed in the substrates 10 includes those having at least about 4 mol % P2O5, wherein (M2O3(mol %)/RxO(mol %))<1, wherein M2O3=Al2O3+B2O3, and wherein RxO is the sum of monovalent and divalent cation oxides present in the glass. The monovalent and divalent cation oxides can be selected from the group consisting of Li2O, Na2O, K2O, Rb2O, Cs2O, MgO, CaO, SrO, BaO, and ZnO. One subset of this family of compositions includes glasses having 0 mol % B2O3. Such glasses are more fully described in U.S. patent application Ser. No. 13/678,013 and U.S. Pat. No. 8,765,262, the contents of which are hereby incorporated by reference in their entirety as if fully set forth below.
Still another illustrative family of compositions that can be employed in the substrates 10 includes those having Al2O3, B2O3, alkali metal oxides, and contains boron cations having three-fold coordination. When ion exchanged, these glasses can have a Vickers crack initiation threshold of at least about 30 kilograms force (kgf). One subset of this family of compositions includes at least about 50 mol % SiO2; at least about 10 mol % R2O, wherein R2O comprises Na2O; Al2O3, wherein −0.5 mol %≤Al2O3(mol %)−R2O (mol %)≤2 mol %; and B2O3, and wherein B2O3(mol %)−(R2O (mol %)−Al2O3(mol %)≥4.5 mol %. Another subset of this family of compositions includes at least about 50 mol % SiO2, from about 9 mol % to about 22 mol % Al2O3; from about 4.5 mol % to about 10 mol % B2O3; from about 10 mol % to about 20 mol % Na2O; from 0 mol % to about 5 mol % K2O; at least about 0.1 mol % MgO and/or ZnO, wherein 0≤MgO+ZnO≤6 mol %; and, optionally, at least one of CaO, BaO, and SrO, wherein 0 mol %≤CaO+SrO+BaO≤2 mol %. Such glasses are more fully described in U.S. patent application Ser. No. 13/903,398, the content of which is incorporated herein by reference in its entirety as if fully set forth below.
Unless otherwise noted, the strengthened glass articles (e.g., articles 100) and associated methods (e.g., methods 200 and 300 depicted in
Similarly, with respect to ceramics, the material chosen for the substrates 10 employed in the strengthened glass articles 100 can be any of a wide range of inorganic crystalline oxides, nitrides, carbides, oxynitrides, carbonitrides, and/or the like. Illustrative ceramics include those materials having an alumina, aluminum titanate, mullite, cordierite, zircon, spinel, perovskite, zirconia, ceria, silicon carbide, silicon nitride, silicon aluminum oxynitride, or zeolite phase.
Similarly, with respect to glass-ceramics, the material chosen for the substrates 10 can be any of a wide range of materials having both a glassy phase and a ceramic phase. Illustrative glass-ceramics include those materials where the glass phase is formed from a silicate, borosilicate, aluminosilicate, or boroaluminosilicate, and the ceramic phase is formed from β-spodumene, β-quartz, nepheline, kalsilite, or carnegieite.
The strengthened glass articles 100, including those that result from the methods of making strengthened articles 200 and 300 (see
Regardless of its composition or physical form, the strengthened glass article 100, as depicted in
In certain aspects of the disclosure, compressive stress (CS) profiles of strengthened glass articles 100 having a glass composition, e.g., that were strengthened using an ion exchange process according to the methods 200 and 300 shown in
According to an embodiment of the strengthened glass article 100 depicted in
Referring now to
Referring again to the method 200 of making strengthened articles 100a depicted in
The method 200 depicted in
Still referring to the method 200 of making strengthened articles 100a depicted in
Referring again to method 200 of making strengthened articles 100a depicted in
Referring again to the method 200 of making strengthened articles 100a depicted in
Referring once again to the method 200 depicted in
Still referring to the method 200 of making strengthened articles 100a depicted in
Once again referring to the method 200 depicted in
Referring again to the method 200 depicted in
Referring once again to the method 200 depicted in
According to some aspects of the disclosure, the method 200 for making a strengthened article 100a depicted in
In one exemplary aspect of the method 200 depicted in
For alumino-silicate glass substrates 10 having a thickness of about 0.3 to 0.8 mm, a DOL>60 μm can be achieved in strengthened glass articles 100a made according to the method 200 depicted in
For embodiments of the method 200 of making strengthened glass articles 100a depicted in
Referring now to
As for the method 300 of making strengthened glass articles 100b depicted in
Still referring to the method 300 of making a strengthened glass article 100b depicted in
Once again referring to the method 300 of making a strengthened glass article 100b depicted in
The method 300 depicted in
Still referring to the method 300 of making a strengthened article 100b, the method 300 can conclude with a step 318 of submersing the substrate 10 in the first ion-exchange bath at a first ion-exchange temperature and duration to form a strengthened article 100b. Upon the completion of the step 318 of the method 300, the strengthened article 100b comprises a compressive stress region 50 extending from the first primary surface 12 and the second primary surface 14 to first and second selected depths 52 and 54, respectively. Further, step 318 can be conducted the same as, or substantially similar to, the step 212 of the method 200 (see
The following examples describe various features and advantages provided by the disclosure, and are in no way intended to limit the invention and appended claims.
In this example, groups of Corning® Gorilla® Glass 3 substrate samples (n=5 per group) were prepared and subjected to methods of making strengthened articles according to principles and concepts of the disclosure (e.g., the methods 200 and 300 of making strengthened articles 100a and 100b depicted in
As detailed below in Table 1, a group of five (5) samples denoted Ex. 1-1 was subjected to a method of strengthening an article consistent with the method 300 (see
As also detailed below in Table 1, three separate comparative groups of five (5) samples denoted Comp. Ex. 1-1, 1-2 and 1-3 were prepared according to substantially the same conditions as those employed in fabricating the groups of samples denoted Ex. 1-1 and 1-2, except that the step for forming the SiO2-containing film was conducted such that the SiO2-containing film has a thickness of less than 0.3 nm. As further detailed below in Table 1, two separate groups of five (5) samples denoted Comp. Ex. 1-4 and 1-5 were prepared according to substantially the same conditions as those employed in fabricating the groups of samples denoted Ex. 1-1 and 1-2, except that no SiO2-containing film was formed in these comparative samples.
Warp measurements were made on each of the groups of samples listed in Table 1. In particular, each sample was measured for warp using a deflectometer (ISRA Vision 650×1300 mm system) on both sides before and after the ion-exchange process step. The maximum warp levels obtained from these measurements on each primary surface, before and after ion exchange processing for a given group of samples (e.g., Ex. 1-1), is reported in Table 1. Further, maximum warp differences are reported in Table 1 that are based on these warp measurements on each side of the samples in a given group. The maximum warp differences (i.e., Δ warp) for each sample group is given by the difference in the maximum warp obtained after and before the ion exchange step for a given sample group. Accordingly, the maximum warp differences may be based on measurements from the AG or the non-anti-glare surface (NAG) side of a sample in a given group.
Referring to Table 1, the samples in the Ex. 1-1 and 1-2 groups, each with a SiO2-containing film having a thickness of about 10 nm, exhibited a change in warp (Δ warp) of 0.032 mm and −0.011 mm, respectively. In contrast, the samples in the Comp. Ex. 1-1, 1-2 and 1-3 groups, each with a SiO2-containing film having a thickness of less than 3 nm, exhibited a change in warp (Δ warp) of 0.150 mm, 0.174 mm and 0.179 mm, respectively. Further, the samples in the Comp. Ex. 1-4 and 1-5 groups, each with no SiO2-containing film, exhibited a change in warp (Δ warp) of 0.157 mm and 0.118 mm, respectively. As such, it is evident from the data in Table 1 that the groups of samples with a SiO2-containing film having a thickness greater than 3 nm (e.g., at about 10 nm) exhibited significantly lower warp levels than the comparative sample groups having no SiO2-containing film or a SiO2-containing film with a thickness of less than 3 nm. Further, the data in Table 1 is supportive of the SiO2-containing film having a thickness from about 5 nanometers to about 20 nanometers.
Aspect (1) pertains to a method of making a strengthened article, comprising: providing an article comprising a glass, glass-ceramic or ceramic composition with a plurality of ion-exchangeable alkali metal ions, a first primary surface and a second primary surface; forming a SiO2-containing film over the first primary surface, wherein the SiO2-containing film comprises a thickness from about 5 nanometers to about 20 nanometers; forming an anti-glare surface integral with the second primary surface; providing a first ion-exchange bath comprising a plurality of ion-exchanging alkali metal ions, each having a larger size than the size of the ion-exchangeable alkali metal ions; and submersing the article in the first ion-exchange bath at a first ion-exchange temperature and duration to form a strengthened article, wherein the strengthened article comprises a compressive stress region extending from the first primary surface and the second primary surface to first and second selected depths, respectively.
Aspect (2) pertains to the method according to Aspect (1), wherein the strengthened article comprises a warp (Δ warp) of 200 microns or less, as determined from warp measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (3) pertains to the method according to Aspect (1), wherein the strengthened article comprises a warp (Δ warp) of 110 microns or less, as determined from warp measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (4) pertains to the method according to Aspect (1), wherein the strengthened article comprises a warp (Δ warp) of 35 microns or less, as determined from warp measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (5) pertains to the method according to any one of Aspects (1) through (4), wherein the article comprises a glass composition selected from the group consisting of soda lime silicate, alkali aluminosilicate, borosilicate and phosphate glasses.
Aspect (6) pertains to the method according to any one of Aspects (1) through (5), wherein a change in haze (Δ haze) and change in gloss (Δ gloss) exhibited by the strengthened article is less than 10%, respectively, as determined from haze and gloss measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (7) pertains to the method according to any one of Aspects (1) through (6), wherein the step of forming a SiO2-containing film is further conducted such that the first primary surface comprises the SiO2-containing film and the step of forming the SiO2-containing film is conducted after masking the second primary surface, and further wherein the step of forming an anti-glare surface is further conducted such that the second primary surface comprises the anti-glare surface and the step of forming the anti-glare surface is conducted after masking the first primary surface with a masking film.
Aspect (8) pertains to a method of making a strengthened article, comprising: providing an article comprising a glass, glass-ceramic or ceramic composition with a plurality of ion-exchangeable alkali metal ions, a first primary surface and a second primary surface; masking the first primary surface with a first masking film; forming an anti-glare surface integral with the second primary surface after the step of masking the first primary surface; removing the first masking film on the first primary surface after the step of forming an anti-glare surface; masking the anti-glare surface with a second masking film; forming a SiO2-containing film over the first primary surface, wherein the SiO2-containing film comprises a thickness from about 5 nanometers to about 20 nanometers, the step of forming a SiO2-containing film conducted after the step of masking the anti-glare surface; removing the second masking film on the anti-glare surface after the step of forming a SiO2-containing film; providing a first ion-exchange bath comprising a plurality of ion-exchanging alkali metal ions, each having a larger size than the size of the ion-exchangeable alkali metal ions; and submersing the article in the first ion-exchange bath at a first ion-exchange temperature and duration to form a strengthened article, the submersing conducted after the step of removing the second masking film, wherein the strengthened article comprises a compressive stress region extending from the first primary surface and the second primary surface to first and second selected depths, respectively.
Aspect (9) pertains to the method according to Aspect (8), wherein the strengthened article comprises a change in warp (Δ warp) of 200 microns or less, as determined from warp measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (10) pertains to the method according to Aspect (8), wherein the strengthened article comprises a change in warp (Δ warp) of 110 microns or less, as determined from warp measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (11) pertains to the method according to Aspect (8), wherein the strengthened article comprises a change in warp (Δ warp) of 35 microns or less, as determined from warp measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (12) pertains to the method according to any one of Aspects (8) through (11), wherein the article comprises a glass composition selected from the group consisting of soda lime silicate, alkali aluminosilicate, borosilicate and phosphate glasses.
Aspect (13) pertains to the method according to any one of Aspects (8) through (12), wherein a change in haze (Δ haze) and change in gloss (Δ gloss) exhibited by the strengthened article is less than 10%, respectively, as determined from haze and gloss measurements on the article before the submersing step and on the strengthened article after the submersing step.
Aspect (14) pertains to a strengthened article made according to the method of any one of Aspects (1) through (13).
Aspect (15) pertains to the strengthened article of Aspect (14), wherein the strengthened article is a component of a vehicle interior.
Aspect (16) pertains to the strengthened article of Aspect (14), wherein the component comprises a display with the strengthened article being a cover glass of the display.
Aspect (17) pertains to a strengthened glass article, comprising: a glass substrate comprising a first primary surface and a second primary surface, and a compressive stress region extending from the first and second primary surfaces to respective first and second selected depths, wherein the second primary surface of the substrate comprises an integrally-formed anti-glare surface, wherein the glass article comprises a change in warp (Δ warp) of 200 microns or less, wherein the first primary surface comprises a SiO2-containing film having a thickness from about 5 nanometers to about 20 nanometers, and further wherein the change in warp is measured before and after formation of the compressive stress region.
Aspect (18) pertains to the glass article of Aspect (17), wherein the glass article comprises a change in warp (Δ warp) of 110 microns or less, and further wherein the change in warp is measured before and after formation of the compressive stress region.
Aspect (19) pertains to the glass article of Aspect (17), wherein the glass article comprises a change in warp (Δ warp) of 35 microns or less, and further wherein the change in warp is measured before and after formation of the compressive stress region.
Aspect (20) pertains to the glass article of any one of Aspects (17) through (19), wherein the glass substrate comprises a glass composition selected from the group consisting of soda lime silicate, alkali aluminosilicate, borosilicate and phosphate glasses.
Aspect (21) pertains to the glass article of any one of Aspects (17) through (20), wherein the portions of the compressive stress region extending from the respective first and second primary surfaces are asymmetric.
Aspect (22) pertains to the glass article of any one of Aspects (17) through (21), wherein the portions of the compressive stress regions extending from the first and second primary surfaces comprise different amounts of ion-exchanged ions from a chemical strengthening process of the glass substrate.
Aspect (23) pertains to the glass article of any one of Aspects (17) through (22), wherein the glass article exhibits a change in haze of less than 1%, and further wherein the change in haze is measured before and after formation of the compressive stress region, the anti-glare surface and the SiO2-containing film.
While exemplary embodiments and examples have been set forth for the purpose of illustration, the foregoing description is not intended in any way to limit the scope of disclosure and appended claims. Accordingly, variations and modifications may be made to the above-described embodiments and examples without departing substantially from the spirit and various principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 201811397677.8 | Nov 2018 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2019/060432 | 11/8/2019 | WO | 00 |
