WO2016014937A1 - Strengthened glass with deep depth of compression - Google Patents

Strengthened glass with deep depth of compression Download PDF

Info

Publication number
WO2016014937A1
WO2016014937A1 PCT/US2015/041976 US2015041976W WO2016014937A1 WO 2016014937 A1 WO2016014937 A1 WO 2016014937A1 US 2015041976 W US2015041976 W US 2015041976W WO 2016014937 A1 WO2016014937 A1 WO 2016014937A1
Authority
WO
WIPO (PCT)
Prior art keywords
glass
μιη
glass article
mpa
compressive stress
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2015/041976
Other languages
English (en)
French (fr)
Inventor
Jonathan David Pesansky
Kevin Barry Reiman
Rostislav Vatchev Roussev
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Corning Inc
Original Assignee
Corning Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Corning Inc filed Critical Corning Inc
Priority to CN201580040362.6A priority Critical patent/CN107108345B/zh
Priority to KR1020177005323A priority patent/KR20170036067A/ko
Priority to EP15750515.7A priority patent/EP3169639B1/en
Priority to DK15750515.7T priority patent/DK3169639T3/da
Priority to CN202310075381.9A priority patent/CN116282965A/zh
Priority to JP2017502188A priority patent/JP2017527513A/ja
Priority to KR1020207011705A priority patent/KR20200045575A/ko
Publication of WO2016014937A1 publication Critical patent/WO2016014937A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C21/00Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface
    • CCHEMISTRY; METALLURGY
    • C03GLASS; MINERAL OR SLAG WOOL
    • C03CCHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
    • C03C21/00Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface
    • C03C21/001Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface in liquid phase, e.g. molten salts, solutions
    • C03C21/002Treatment of glass, not in the form of fibres or filaments, by diffusing ions or metals in the surface in liquid phase, e.g. molten salts, solutions to perform ion-exchange between alkali ions
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/30Investigating strength properties of solid materials by application of mechanical stress by applying a single impulsive force, e.g. by falling weight
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00Technologies relating to the processing of minerals
    • Y02P40/50Glass production, e.g. reusing waste heat during processing or shaping

Definitions

  • the disclosure relates to a chemically strengthened glass article. More particularly, the disclosure relates to chemically strengthened glasses having a deep compressive surface layer.
  • Strengthened glasses widely used in electronic devices as cover plates or windows for portable or mobile electronic communication and entertainment devices, such as cellular phones, smart phones, tablets, video players, information terminal (IT) devices, laptop computers and the like, as well as in other applications.
  • I information terminal
  • strengthened glasses it has become more important to develop strengthened glass materials having improved survivability, especially when subjected to tensile stresses and/or relatively deep flaws caused by contact with hard/sharp surfaces.
  • the compressive stress profile includes a single linear segment extending from the surface to the depth of compression DOC.
  • the compressive stress profile includes two approximately linear portions: the first portion extending from the surface to a relatively shallow depth and having a steep slope; and a second portion extending from the shallow depth to the depth of compression.
  • the strengthened glass has a 60% survival rate when dropped from a height of 100 cm in an inverted ball drop test and an equibiaxial flexural strength of at least 10 kgf as determined by abraded ring on ring testing. Methods of achieving such stress profiles are also described.
  • one aspect of the disclosure is to provide a glass article, having a compressive region having a compressive stress CS S of at least about 150 MPa at a surface of the glass article.
  • the compressive region extends from the surface to a depth of compression DOC of at least about 45 ⁇ and has a compressive stress profile and a compressive stress profile having a first portion a extending to a depth d a of at least about 45 ⁇ from the surface and having a slope m a , wherein 2 MPa/ ⁇ m a ⁇ 8 MPa/ ⁇ , and optionally a second portion a' extending from the surface to a depth d a - of at least about 3 ⁇ , wherein 40 MPa/ ⁇ m a - ⁇ 200
  • a second aspect of the disclosure is to provide a glass article having a compressive layer having a compressive stress CS S of at least about 150 MPa at a surface of the glass article.
  • the compressive layer extends from the surface to a depth of compression DOC of at least about 45 ⁇ and has a compressive stress profile.
  • the compressive stress profile comprises: a first portion a extending from the surface to a depth d a and having a slope m a , wherein 3 ⁇ d a ⁇ 8 ⁇ and 40 MPa/ ⁇ m a ⁇ 200 MPa/ ⁇ ; and a second portion b extending from d a to up to the depth of compression DOC and having a slope ni b , wherein 2 MPa/ ⁇ ni b ⁇ 8MPa ⁇ m.
  • a glass article having a compressive region having a compressive stress CS S of at least about 150 MPa at a surface of the glass article is provided.
  • the compressive region extends from the surface to a depth of compression DOC of at least about 45 ⁇ and has a compressive stress profile.
  • the compressive stress profile has a first portion a extending from the surface to a depth d a and a slope m a , wherein the depth d a is equal to the depth of compression and 2 MPa/ ⁇ m a ⁇ 8
  • a fourth aspect of the disclosure is to provide a glass article having a compressive region under a compressive stress CS S of at least about 120 MPa at a surface of the glass article.
  • the compressive region extends from the surface to a depth of compression DOC of at least about 70 ⁇ and has a compressive stress profile.
  • the compressive stress profile has a first linear portion a extending from the surface to a depth d a and a slope m a , wherein the depth d a is equal to the depth of compression and 0.7 MPa/ ⁇ m a ⁇ 2.0 MPa/ ⁇ .
  • a fifth aspect of the disclosure is to provide a method of producing a strengthened glass article having at least one compressive stress layer extending from a surface of the strengthened glass article to a depth of compression DOC of at least about 45 ⁇ .
  • the method comprises: conducting a first ion exchange step by immersing an alkali aluminosilicate glass article in a first ion exchange bath at a temperature of greater than 400°C for a time sufficient such that the compressive stress layer has a depth of at least 45 ⁇ after the first ion exchange step; and conducting a second ion exchange step by immersing the alkali aluminosilicate glass article in a second ion exchange bath different from the first ion exchange bath at a temperature of at least about 350°C for a time sufficient to produce the compressive layer having the depth of compression DOC of at least about 45 ⁇ .
  • a sixth aspect of the disclosure is to provide a strengthened glass, having an inner region under a central tension CT, and at least one compressive stress layer under a compressive stress CS.
  • the compressive stress layer extends from a surface of the glass to a depth of compression of at least about 45 ⁇ and is adjacent to the inner region.
  • the strengthened glass has an equibiaxial flexural strength of at least 10 kgf as determined by abraded ring on ring testing.
  • a seventh aspect of the disclosure is to provide a strengthened glass, having an inner region under a central tension CT, and at least one compressive stress layer under a compressive stress CS.
  • the compressive stress layer extends from a surface of the glass to a depth of compression of at least about 45 ⁇ and is adjacent to the inner region.
  • the strengthened glass has at least a 60% survival rate when dropped in an inverted ball drop test from a height of at least 100 cm onto a drop surface.
  • FIGURE 1 is a schematic cross-sectional view of a chemically strengthened glass article
  • FIGURE 2 is a schematic representation of a compressive stress profile obtained by a single step ion exchange process
  • FIGURE 3 is a schematic representation of a compressive stress profile obtained by a two-step ion exchange process
  • FIGURE 4a is a plot of spectra of refractive index profiles for TM and
  • FIGURE 4b is a plot of the compressive stress profile determined from the index profiles shown in FIG. 4a;
  • FIGURE 5a is a plot of TM and TE refractive index profiles reconstructed from spectra of bound optical modes for TM and TE polarization measured for ion exchanged glass sample b having a thickness of 0.4 mm;
  • FIGURE 5b is a plot of the compressive stress profile determined from the spectra shown in FIG. 5 a;
  • FIGURE 5c is a plot of the compressive stress profile of the sample in
  • FIGS. 5a and 5b following a second ion exchange step
  • FIGURE 6a is a plot of TM and TE refractive index profiles reconstructed from spectra of bound optical modes for TM and TE polarization measured for ion exchanged glass sample c having a thickness of 0.4 mm;
  • FIGURE 6b is a plot of the compressive stress profile determined from the spectra shown in FIG. 6a;
  • FIGURE 7a is a plot of TM and TE refractive index profiles reconstructed from spectra of bound optical modes for TM and TE polarization measured for ion exchanged glass sample d having a thickness of 0.5 mm;
  • FIGURE 7b is a plot of the compressive stress profile determined from the spectra shown in FIG. 7a;
  • FIGURE 8a is a plot of TM and TE refractive index profiles reconstructed from spectra of bound optical modes for TM and TE polarization measured for ion exchanged glass sample e having a thickness of 0.5 mm;
  • FIGURE 8b is a plot of the compressive stress profile determined from the spectra shown in FIG. 8a;
  • FIGURE 9a is a plot of the compressive stress profile for ion exchanged glass sample f having a thickness of 0.7 mm;
  • FIGURE 9b is a plot of the compressive stress profile of the sample in in FIG. 9a following a second ion exchange step
  • FIGURE 10a is a plot of the compressive stress profile for ion exchanged glass sample g having a thickness of 0.8 mm;
  • FIGURE 10b is a plot of the compressive stress profile of the sample in in FIG. 10a following a second ion exchange step
  • FIGURE 11 is a plot of the compressive stress profile for ion exchanged glass sample i having a thickness of 0.9 mm following two ion exchange steps;
  • FIGURE 12a is a plot of the compressive stress profile for ion exchanged glass sample j having a thickness of 1.0 mm;
  • FIGURE 12b is a plot of the compressive stress profile determined for the sample of FIGURE 12a following a second ion exchange step
  • FIGURE 13 a is a plot of the compressive stress profile for ion exchanged glass sample k having a thickness of 0.55 mm;
  • FIGURE 13b is a plot of the compressive stress profile determined for the sample of FIGURE 13a following a second ion exchange step
  • FIGURE 14a is a graphical representation of a photograph showing strengthened glass articles 1) exhibiting frangible behavior upon fragmentation; and 2) exhibiting non- frangible behavior upon fragmentation;
  • FIGURE 14b is a graphical representation of a photograph showing strengthened glass sheets that exhibit non-frangible behavior upon fragmentation.
  • FIGURE 15a is a schematic cross-sectional view of an embodiment of the apparatus that is used to perform the inverted ball on sandpaper (IBoS) test described in the present disclosure
  • FIGURE 15b is a schematic cross-sectional representation of the dominant mechanism for failure due to damage introduction plus bending that typically occurs in strengthened glass articles that are used in mobile or hand held electronic devices;
  • FIGURE 15c is a method 300 of conducting the IBoS test in the apparatus described herein;
  • FIGURE 16 is a graphical comparison of failure rates of strengthened glasses at varying DOL and CS values when subjected to the IBoS test described in the present disclosure
  • FIGURE 17 is a plot of the compressive stress profile for ion exchanged glass sample m having a thickness of 0.8 mm;
  • FIGURE 18 is a plot of drop height at failure as a function of depth of layer DOL, as measured by FSM, of ion exchanged glass samples;
  • FIGURE 19 is a schematic cross- sectional view of a ring on ring apparatus.
  • FIGURE 20 is a plot of abraded ring on ring data as a function of sample thickness for two strengthened alkali aluminosilicate glasses.
  • glass article and “glass articles” are used in their broadest sense to include any object made wholly or partly of glass. Unless otherwise specified, all glass compositions are expressed in terms of mole percent (mol%) and all ion exchange bath compositions are expressed in terms of weight percent (wt%).
  • depth of layer and “DOL” refer to the depth of the compressive layer as determined by surface stress meter (FSM) measurements using commercially available instruments such as the FSM-6000.
  • depth of compression and "DOC” refer to the depth at which the stress within the glass changes from compressive to tensile stress. At the DOC, the stress crosses from a positive (compressive) stress to a negative (tensile) stress and thus has a value of zero.
  • compressive stress (CS) and central tension (CT) are expressed in terms of megaPascals (MPa)
  • the term "fracture” means that a crack propagates across the entire thickness and/or entire surface of a substrate when that substrate is dropped or impacted with an object, unless otherwise specified.
  • compression is expressed as a negative ( ⁇ 0) stress and tension is expressed as a positive (>0) stress.
  • and central tension or tensile stress is expressed as a negative value in order to better visualize the compressive stress profiles described herein.
  • the "slope (m)" refers to the slope of a segment or portion of the stress profile that closely approximates a straight line.
  • the predominant slope is defined as the average slope for regions that are well approximated as straight segments. These are regions in which the absolute value of the second derivative of the stress profile is smaller than the ratio of the absolute value of the first derivative, and approximately half the depth of the region.
  • the essentially straight segment is the portion for each point of which the absolute value of the second derivative of the stress profile is smaller than the absolute value of the local slope of the stress profile divided by the depth at which the absolute value of the stress changes by a factor of 2.
  • the straight portion of the segment is the region for which the local second derivative of the stress profile has an absolute value that is smaller than the absolute value of the local slope of the stress profile divided by half the DOC.
  • a straight portion of the profile is a region where
  • a straight portion of the profile is a region where ⁇ ' ⁇ )
  • the straight segments are selected as regions where
  • slope m of linear segments of the compressive stress profiles described herein are given as absolute values of the slope— - i.e., m, as recited herein, is equal to
  • Described herein are glass articles that are chemically strengthened by ion exchange to obtain a prescribed compressive stress profile and thus achieve survivability when dropped onto a hard, abrasive surface from a prescribed height.
  • Ion exchange is commonly used to chemically strengthen glasses.
  • alkali cations within a source of such cations e.g., a molten salt, or "ion exchange,” bath
  • a source of such cations e.g., a molten salt, or "ion exchange,” bath
  • CS compressive stress
  • potassium ions from the cation source are often exchanged with sodium ions within the glass.
  • the compressive layer extends from the surface to a depth within the glass.
  • FIG. 1 A cross-sectional schematic view of a planar ion exchanged glass article is shown in FIG. 1.
  • Glass article 100 has a thickness t, first surface 1 10, and second surface 112. While the embodiment shown in FIG. 1 depicts glass article 100 as a flat planar sheet or plate, glass article may have other configurations, such as three dimensional shapes or non-planar configurations.
  • Glass article 100 has a first compressive region 120 extending from first surface 1 10 to a depth of compression (DOC) di into the bulk of the glass article 100.
  • DOC depth of compression
  • glass article 100 also has a second compressive region 122 extending from second surface 1 12 to a second depth of compression (DOC) 02.
  • Glass article also has a central region 130 that extends from di to d2.
  • Central region 130 is under a tensile stress having a value at the center of the central region 130 called central tension or center tension (CT).
  • CT central tension or center tension
  • the tensile stress of region 130 balances or counteracts the compressive stresses of regions 120 and 122.
  • the depths di, dj of first and second compressive regions 120, 122 protect the glass article 100 from the propagation of flaws introduced by sharp impact to first and second surfaces 110, 112 of glass article 100, while the compressive stress minimizes the likelihood of a flaw growing and penetrating through the depth di, 02 of first and second compressive regions 120, 122.
  • the strengthened glass articles described herein have a maximum compressive stress CS S of at least about 150 megaPascals (MPa). In some embodiments, the maximum compressive stress CS S is at least about 210 MPa and, in other embodiments, at least about 300 MPa. In some embodiments, the maximum compressive stress CS S is located at the surface (1 10, 112 in FIG. 1). In other embodiments, however, the maximum compressive CS S may be located in the compressive region (120, 122) at some depth below the surface of the glass article. The compressive region extends from the surface of the glass article to a depth of compression DOC of at least about 45 microns ( ⁇ ). In some embodiments, DOC is at least about 60 ⁇ .
  • DOC is at least about 70 ⁇ , in some embodiments, at least about 80 ⁇ , and, in still other embodiments, DOC is at least about 90 ⁇ .
  • the depth of compression DOC is at least 100 ⁇ and, in some embodiments at least about 140 ⁇ . In certain embodiments, the depth of compression has a maximum value of about 100 ⁇ .
  • the compressive stress varies as a function of depth below the surface of the strengthened glass article, producing a compressive stress profile in the compressive region.
  • the compressive stress profile is substantially linear within the compression region, as schematically shown in FIG. 2.
  • the compressive stress behaves substantially linearly, resulting in a straight line a having a slope m a , expressed in MPa/ ⁇ , that intercepts the vertical y (CS) axis at CS S .
  • CS profile a intercepts the x axis at the depth of compression DOC.
  • the total stress is zero.
  • the glass article is in tension CT, reaching a central value CT.
  • the compressive stress profile a of the glass article described herein has a slope m a that is within a specified range.
  • slope m a of line a lies between upper boundary 82 and lower boundary ⁇ ; i.e., 82 > m a > ⁇ .
  • 2 MPa/ ⁇ m a 200 MPa/ ⁇ .
  • 2 MPa/ ⁇ m a ⁇ 8 MPa/ ⁇ in some embodiments, 3 MPa/ ⁇ m a ⁇ 6 MPa/ ⁇ m, and in still other embodiments, 2 MPa/ ⁇ m a ⁇ 4.5 MPa/ ⁇ .
  • the slope m a is less than about 1.5 MPa/ ⁇ and, in some embodiments, from about 0.7 MPa/ ⁇ to about 2 MPa/ ⁇ .
  • the slope m a has such values and the depth of compression DOC is at least about 100 ⁇ , the resistance of the strengthened glass to at least one type of failure modes (e.g., very deep puncture) that may be prevalent in field failures certain device designs is particularly advantageous.
  • the compressive stress profile is a combination of more than one substantially linear function, as schematically shown in FIG. 3.
  • the compressive stress profile has a first segment or portion a' and a second segment or portion b.
  • First portion a exhibits substantially linear behavior from the strengthened surface of the glass article to a depth d a .
  • Portion a' has a slope m a - and y intercept CS S .
  • Second portion b of the compressive stress profile extends from approximately depth d a to depth of compression DOC, and has a slope m b .
  • the compressive stress CS(d a ) at depth d a is given by the expression
  • depth d a is in a range from about 3 ⁇ to about 8 ⁇ ; i.e., 3 ⁇ ⁇ d a ⁇ 8 ⁇ . In other embodiments, 3 ⁇ ⁇ d a ⁇ ⁇ . In yet other embodiments, 3 ⁇ d a ⁇ 12 ⁇ .
  • the compressive stress profile may include additional segments.
  • different linear portions or segments of the compressive stress profile may be joined by a transitional region (not shown) in which the slope of the profile transitions from a first slope to a second slope (e.g., from m a' to m ).
  • the slope of portion a' of the compressive stress profile is much steeper than the slope of portion b - i.e., I m a - 1 >
  • the compressive stress profiles a and b of the glass article described herein have slopes m a - and m b , respectively, that are within specified ranges.
  • slope m a - of line a' lies between upper boundary 83 and lower boundary ⁇ 4 and slope nib of line b lies between upper boundary 85 and lower boundary ⁇ ; i.e., ⁇ 4 > m a - > 8 3 and ⁇ > m b > 85.
  • Compressive stress CS and depth of the compressive layer DOL are measured using those means known in the art.
  • Such means include, but are not limited to, measurement of surface stress (FSM) using commercially available instruments such as the FSM-6000, manufactured by Luceo Co., Ltd. (Tokyo, Japan), or the like, and methods of measuring compressive stress and depth of layer are described in ASTM 1422C-99, entitled “Standard Specification for Chemically Strengthened Flat Glass,” and ASTM 1279.19779 “Standard Test Method for Non- Destructive Photoelastic Measurement of Edge and Surface Stresses in Annealed, Heat- Strengthened, and Fully-Tempered Flat Glass,” the contents of which are incorporated herein by reference in their entirety.
  • FSM surface stress
  • SOC stress optical coefficient
  • fiber and four point bend methods both of which are described in ASTM standard C770-98 (2008), entitled “Standard Test Method for Measurement of Glass Stress-Optical Coefficient,” the contents of which are incorporated herein by reference in their entirety, and a bulk cylinder method.
  • CT (CS ⁇ DOL)/(t - 2 DOL) (8), where t is the thickness, expressed in microns ( ⁇ ), of the glass article.
  • t is the thickness, expressed in microns ( ⁇ ), of the glass article.
  • central tension CT and compressive stress CS are expressed herein in megaPascals (MPa)
  • thickness t is expressed in either microns ( ⁇ ) or millimeters (mm)
  • depth of layer DOL is expressed in microns ( ⁇ ) or millimeters (mm), consistent with the representation of t..
  • the FSM technique may suffer from contrast issues which affect the observed DOL value. At deeper DOL values, there may be inadequate contrast between the TE and TM spectra, thus making the calculation of the difference between TE and TM spectra - and determining the DOL - more difficult.
  • the FSM software analysis is incapable of determining the compressive stress profile (i.e., the variation of compressive stress as a function of depth within the glass).
  • the FSM technique is incapable of determining the depth of layer resulting from the ion exchange of certain elements such as, for example, ion exchange of sodium for lithium.
  • the detailed index profiles are obtained from the mode spectra by using the inverse Wentzel-Kramers-Brillouin (IWKB) method.
  • the detailed index profiles are obtained by fitting the measured mode spectra to numerically calculated spectra of pre-defined functional forms that describe the shapes of the index profiles and obtaining the parameters of the functional forms from the best fit.
  • the detailed stress profile S(z) is calculated from the difference of the recovered TM and TE index profiles by using a known value of the stress-optic coefficient (SOC):
  • the birefringence ⁇ ( ⁇ ) - ⁇ ( ⁇ ) at any depth z is a small fraction (typically on the order of 1%) of either of the indices n T M(z) and ⁇ ( ⁇ ).
  • Obtaining stress profiles that are not significantly distorted due to noise in the measured mode spectra requires determination of the mode effective indices with precision on the order of 0.00001 RIU.
  • the methods disclosed in Roussev I further include techniques applied to the raw data to ensure such high precision for the measured mode indices, despite noise and/or poor contrast in the collected TE and TM mode spectra or images of the mode spectra. Such techniques include noise-averaging, filtering, and curve fitting to find the positions of the extremes corresponding to the modes with sub-pixel resolution.
  • Roussev II Unlike Roussev I, in which discrete spectra of modes are identified, the methods disclosed in Roussev II rely on careful analysis of the angular intensity distribution for TM and TE light reflected by a prism- sample interface in a prism-coupling configuration of measurements. The contents of the above applications are incorporated herein by reference in their entirety.
  • derivatives of the TM and TE signals are determined after application of some combination of the aforementioned signal conditioning techniques.
  • the locations of the maximum derivatives of the TM and TE signals are obtained with sub-pixel resolution, and the surface birefringence is proportional to the spacing of the above two maxima, with a coefficient determined as before by the apparatus parameters.
  • the apparatus comprises several enhancements, such as using a light-scattering surface (static diffuser) in close proximity to or on the prism entrance surface to improve the angular uniformity of illumination, a moving diffuser for speckle reduction when the light source is coherent or partially coherent, and light-absorbing coatings on portions of the input and output facets of the prism and on the side facets of the prism, to reduce parasitic background which tends to distort the intensity signal.
  • the apparatus may include an infrared light source to enable measurement of opaque materials.
  • Roussev II discloses a range of wavelengths and attenuation coefficients of the studied sample, where measurements are enabled by the described methods and apparatus enhancements.
  • the range is defined by ⁇ 5 ⁇ ⁇ 250 ⁇ 5 , where a s is the optical attenuation coefficient at measurement wavelength ⁇ , and Os is the expected value of the stress to be measured with typically required precision for practical applications.
  • This wide range allows measurements of practical importance to be obtained at wavelengths where the large optical attenuation renders previously existing measurement methods inapplicable.
  • Roussev II discloses successful measurements of stress-induced birefringence of opaque white glass-ceramic at a wavelength of 1550 nm, where the attenuation is greater than about 30 dB/mm.
  • the glass articles may be chemically strengthened by ion exchange.
  • ions at or near the surface of the glass are replaced by - or exchanged with - larger ions usually having the same valence or oxidation state.
  • ions in the surface layer of the glass and the larger ions are monovalent alkali metal cations, such as Na + (when Li + is present in the glass), K + , Rb + , and Cs + .
  • monovalent cations in the surface layer may be replaced with monovalent cations other than alkali metal cations, such as Ag + or the like.
  • Ion exchange processes are typically carried out by immersing a glass article in a molten salt bath containing the larger ions to be exchanged with the smaller ions in the glass.
  • parameters for the ion exchange process including, but not limited to, bath composition and temperature, immersion time, the number of immersions of the glass in a salt bath (or baths), use of multiple salt baths, additional steps such as annealing, washing, and the like, are generally determined by the composition of the glass and the desired depth of layer and compressive stress of the glass that result from the strengthening operation.
  • ion exchange of alkali metal-containing glasses may be achieved by immersion in at least one molten bath containing a salt such as, but not limited to, nitrates, sulfates, and chlorides of the larger alkali metal ion.
  • a salt such as, but not limited to, nitrates, sulfates, and chlorides of the larger alkali metal ion.
  • the temperature of the molten salt bath typically is in a range from about 380°C up to about 450°C, while immersion times range from about 15 minutes up to about 40 hours. However, temperatures and immersion times different from those described above may also be used.
  • ion exchange processes in which glass is immersed in multiple ion exchange baths, with washing and/or annealing steps between immersions are described in U.S. Patent No.
  • the compressive stress is created by chemically strengthening the glass article, for example, by the ion exchange processes previously described herein, in which a plurality of first metal ions in the outer region of the glass article is exchanged with a plurality of second metal ions so that the outer region comprises the plurality of the second metal ions.
  • Each of the first metal ions has a first ionic radius and each of the second alkali metal ions has a second ionic radius.
  • the second ionic radius is greater than the first ionic radius, and the presence of the larger second alkali metal ions in the outer region creates the compressive stress in the outer region.
  • At least one of the first metal ions and second metal ions are ions of an alkali metal.
  • the first ions may be ions of lithium, sodium, potassium, and rubidium.
  • the second metal ions may be ions of one of sodium, potassium, rubidium, and cesium, with the proviso that the second alkali metal ion has an ionic radius greater than the ionic radius than the first alkali metal ion.
  • the glass is strengthened in a single ion exchange step to produce the compressive stress profile shown in FIG. 2.
  • the glass is immersed in a molten salt bath containing a salt of the larger alkali metal cation.
  • the molten salt bath contains or consists essentially of salts of the larger alkali metal cation.
  • small amounts - in some embodiments, less that about 10 wt%, in some embodiments, less than about 5 wt%, and, in other embodiments less than about 2 wt% - of salts of the smaller alkali metal cation may be present in the bath.
  • salts of the smaller alkali metal cation may comprise at least about 30 wt%, or at least about 40 wt%, or from about 40 wt% to about 75 wt% of the ion exchange bath.
  • This single ion exchange process may take place at a temperature of at least about 400°C and, in some embodiments, at least about 440°C, for a time sufficient to achieve the desired depth of compression DOC.
  • the single step ion exchange process may be conducted for at least eight hours, depending on the composition of the bath.
  • the glass is strengthened in a two-step or dual ion exchange method to produce the compressive stress profile shown in FIG. 3.
  • the first step of the process the glass is ion exchanged in the first molten salt bath described above.
  • the glass is immersed in a second ion exchange bath.
  • the second ion exchange bath is different - i.e., separate from and, in some embodiments, having a different composition - from the first bath.
  • the second ion exchange bath contains only salts of the larger alkali metal cation, although, in some embodiments small amounts of the smaller alkali metal cation (e.g., ⁇ 2 wt%; ⁇ 3 wt%) may be present in the bath, in addition, the immersion time and temperature of the second ion exchange step may differ from those of the first ion exchange step.
  • the second ion exchange step is carried out at a temperature of at least about 350°C and, in other embodiments, at least about 380°C.
  • the duration of the second ion exchange step is sufficient to achieve the desired depth d a of the shallow segment, in some embodiments, may be 30 minutes or less. In other embodiments, the duration is 15 minutes or less and, in some embodiments, in a range from about 10 minutes to about 60 minutes.
  • the second ion exchange bath is different than the first ion exchange bath, because the second ion exchange step is directed to delivering a different concentration of the larger cation or, in some embodiments, a different cation altogether, to the alkali aluminosilicate glass article than the first ion exchange step.
  • the second ion exchange bath may comprise at least about 95% by weight of a potassium composition that delivers potassium ions to the alkali aluminosilicate glass article.
  • the second ion exchange bath may comprise from about 98% to about 99.5% by weight of the potassium composition.
  • the second ion exchange bath may, in further embodiments, comprise 0-5% by weight, or about 0.5-2.5% by weight of at least one sodium salt, for example, NaN0 3 .
  • the potassium salt is K O 3 .
  • the temperature of the second ion exchange step may be 380°C or greater.
  • the purpose of the second ion exchange step is to form a "spike" increase the compressive stress in the region immediately adjacent to the surface of the glass article, as represented by portion a' of the stress profile shown in FIG. 3.
  • the glass articles described herein may comprise or consist of any glass that is chemically strengthened by ion exchange.
  • the glass is an alkali aluminosilicate glass.
  • the alkali aluminosilicate glass comprises or consists essentially of: at least one of alumina and boron oxide, and at least one of an alkali metal oxide and an alkali earth metal oxide, wherein -15 mol% ⁇ (R2O + R'O - AI2O3 - Zr0 2 ) - B2O3 ⁇ 4 mol%, where R is one of Li, Na, K, Rb, and Cs, and R' is at least one of Mg, Ca, Sr, and Ba.
  • the alkali aluminosilicate glass comprises or consists essentially of: from about 62 mol% to about 70 mol.% Si0 2 ; from 0 mol% to about 18 mol% A1 2 0 3 ; from 0 mol% to about 10 mol% B 2 0 3 ; from 0mol% to about 15 mol% Li 2 0; from 0 mol% to about 20 mol% Na 2 0; from 0 mol% to about 18 mol% K 2 0; from 0 mol% to aboutl7 mol% MgO; from 0 mol% to aboutl8 mol% CaO; and from 0 mol% to about 5 mol% Zr0 2 .
  • the glass comprises alumina and boron oxide and at least one alkali metal oxide, wherein -15 mol% ⁇ (R 2 0 + R'O - A1 2 0 3 - Zr0 2 ) - B 2 0 3 ⁇ 4 mol%, where R is at least one of Li, Na, K, Rb, and Cs, and R' is at least one of Mg, Ca, Sr, and Ba; wherein 10 ⁇ A1 2 0 3 + B 2 0 3 + Zr0 2 ⁇ 30 and 14 ⁇ R 2 0 + R'O ⁇ 25; wherein the silicate glass comprises or consists essentially of: 62-70 mol.% Si0 2 ; 0-18 mol% A1 2 0 3 ; 0-10 mol% B 2 0 3 ; 0-15 mol% Li 2 0; 6-14 mol% Na 2 0; 0-18 mol% K 2 0; 0-17 mol% MgO; 0-18 mol%
  • the alkali aluminosilicate glass comprises or consists essentially of: from about 60 mol% to about 70 mol% Si0 2 ; from about 6 mol% to about 14 mol% A1 2 0 3 ; from 0 mol% to about 15 mol% B 2 0 3 ; from 0 mol% to about 15 mol% Li 2 0; from 0 mol% to about 20 mol% Na 2 0; from 0 mol% to about 10 mol% K 2 0; from 0 mol% to about 8 mol% MgO; from 0 mol% to about 10 mol% CaO; from 0 mol% to about 5 mol% Zr0 2 ; from 0 mol% to about 1 mol% Sn0 2 ; from 0 mol% to about 1 mol% Ce0 2 ; less than about 50 ppm As 2 0 3 ; and less than about 50 ppm Sb 2 0 3 ; wherein 12 mol%
  • the alkali aluminosilicate glass comprises or consists essentially of: 60-70 mol% Si0 2 ; 6-14 mol% A1 2 0 3 ; 0-3 mol% B 2 0 3 ; 0-1 mol% Li 2 0; 8-18 mol% Na 2 0; 0-5 mol% K 2 0; 0-2.5 mol% CaO; above 0 to 3 mol % Zr0 2 ; 0-1 mol% Sn0 2 ; and 0-1 mol% Ce0 2 , wherein 12 mol% ⁇ Li 2 0 + Na 2 0 + K 2 0 ⁇ 20 mol%, and wherein the silicate glass comprises less than 50 ppm As 2 0 3 .
  • the alkali aluminosilicate glass comprises or consists essentially of: 60-72 mol% Si0 2 ; 6-14 mol% A1 2 0 3 ; 0-3 mol% B 2 0 3 ; 0-1 mol% Li 2 0; 0-20 mol% Na 2 0; 0-10 mol% K 2 0; 0-2.5 mol% CaO; 0-5 mol% Zr0 2 ; 0-1 mol% Sn0 2 ; and 0-1 mol% Ce0 2 , wherein 12 mol% ⁇ Li 2 0 + Na 2 0 + K 2 0 ⁇ 20 mol%, and wherein the silicate glass comprises less than 50 ppm As 2 0 3 and less than 50 ppm Sb 2 0 3 .
  • the alkali aluminosilicate glass comprises S1O2 and Na20, wherein the glass has a temperature T35kp at which the glass has a viscosity of 35 kilo poise (kpoise), wherein the temperature Tb rea kd o wn at which zircon breaks down to form ⁇ (3 ⁇ 4 and S1O2 is greater than T35k p .
  • the alkali aluminosilicate glass comprises or consists essentially of: from about 61 mol % to about 75 mol% S1O2; from about 7 mol % to about 15 mol% AI2O3; from 0 mol% to about 12 mol% B2O3; from about 9 mol % to about 21 mol%Na20; from 0 mol % to about 4 mol% K2O; from 0 mol% to about 7 mol% MgO; and 0 mol% to about 3 mol% CaO.
  • the glass is described in U.S. Patent Application No. 12/856,840 by Matthew J.
  • the alkali aluminosilicate glass comprises at least 50 mol% S1O2 and at least one modifier selected from the group consisting of alkali metal oxides and alkaline earth metal oxides, wherein [(AI2O 3 (mol%) + B203(mol%))/( ⁇ alkali metal modifiers (mol%))] > 1.
  • the alkali aluminosilicate glass comprises or consists essentially of: from 50 mol% to about 72 mol% S1O2; from about 9 mol% to about 17 mol% AI2O3; from about 2 mol% to about 12 mol% B2O 3 ; from about 8 mol% to about 16 mol% Na 2 0; and from 0 mol% to about 4 mol% K 2 0.
  • the glass comprises or consists essentially of: at least 58 mol% S1O2; at least 8 mol% Na 2 0; from 5.5 to 12 mol% B 2 0 3 ; and AI2O 3 , wherein [(A1 2 0 3 (mol%) + B 2 0 3 (mol%))/( ⁇ alkali metal modifiers (mol%))] > 1 , Al 2 0 3 (mol%) > B 2 0 3 (mol%), 0.9 ⁇ R2O/AI2O3 ⁇ 1.3.
  • the glass is described in U.S. Patent No. 8,586,492, entitled "Crack And Scratch Resistant Glass and Enclosures Made Therefrom," filed August 18, 2010, by Kristen L.
  • the alkali aluminosilicate glass comprises
  • the alkali aluminosilicate glass comprises or consists essentially of: from about 40 mol% to about 70 mol% S1O2; from 0 mol% to about 28 mol% B20 3 ; from 0 mol% to about 28 mol% Ai20 3 ; from about 1 mol% to about 14 mol% P2O5; and from about 12 mol% to about 16 mol% R2O; and, in certain embodiments, from about 40 to about 64 mol% S1O2; from 0 mol% to about 8 mol% B20 3 ; from about 16 mol% to about 28 mol% Ai 2 0 3 ; from about 2 mol% to about 12% P2O5; and from about 12 mol% to about 16 mol% R 2 O.
  • the alkali aluminosilicate glass comprises at least about 50 mol% S1O2 and at least about 1 1 mol% Na 2 0, and the compressive stress is at least about 900 MPa.
  • the glass further comprises A1 2 0 3 and at least one of B 2 0 3 , K 2 0, MgO and ZnO, wherein -340 + 27.1 -A1 2 0 3 - 28.7-B 2 0 3 + 15.6-Na 2 0 - 61.4-K 2 0 + 8.1 -(MgO + ZnO) > 0 mol%.
  • the glass comprises or consists essentially of: from about 7 mol% to about 26 mol% Ai 2 0 3 ; from 0 mol% to about 9 mol% B 2 0 3 ; from about 11 mol% to about 25 mol% Na 2 0; from 0 mol% to about 2.5 mol% K 2 O; from 0 mol% to about 8.5 mol% MgO; and from 0 mol% to about 1.5 mol% CaO.
  • the glass is described in U.S. Patent Application No. 13/533,298, by Matthew J. Dejneka et al, entitled “Ion Exchangeable Glass with High Compressive Stress," filed June 26, 2012, and claiming priority to U.S. Provisional Patent Application No. 61/503,734, filed July 1, 2011. The contents of all of the above are incorporated herein by reference in their entirety.
  • the alkali aluminosilicate glass is ion exchangeable and comprises: at least about 50 mol% SiC ⁇ ; at least about 10 mol% R2O, wherein R2O comprises a20; AI2O3; and B2O3, wherein B2O3 - (R2O - AI2O3) > 3 mol%.
  • the glass comprises: at least about 50 mol% S1O2; at least about 10 mol% R2O, wherein R 2 0 comprises Na 2 0; AI2O 3 , wherein Al 2 0 3 (mol%) ⁇ R 2 0(mol%); and 3-4.5 mol% B 2 0 3 , wherein B 2 0 3 (mol%) - (R20(mol%) - Al203(mol%)) > 3 mol%.
  • the glass comprises or consists essentially of: at least about 50 mol% S1O2; from about 9 mol% to about 22 mol% AI2O 3 ; from about 3 mol% to about 10 mol% B2O 3 ; from about 9 mol% to about 20 mol% a20; from 0 mol% to about 5 mol% K2O; at least about 0.1 mol% MgO, ZnO, or combinations thereof, wherein 0 ⁇ MgO ⁇ 6 and 0 ⁇ ZnO ⁇ 6 mol%; and, optionally, at least one of CaO, BaO, and SrO, wherein 0 mol% ⁇ CaO + SrO + BaO ⁇ 2 mol%.
  • the glass when ion exchanged, has a Vickers crack initiation threshold of at least about 10 kgf
  • Such glasses are described in U.S. Patent Application No. 14/197,658, filed May 28, 2013, by Matthew J. Dejneka et al., entitled “Zircon Compatible, Ion Exchangeable Glass with High Damage Resistance,” which is a continuation of U.S. Patent Application No. 13/903,433, filed May 28, 2013, by Matthew J. Dejneka et al, entitled “Zircon Compatible, Ion Exchangeable Glass with High Damage Resistance,” both claiming priority to Provisional Patent Application No. 61/653,489, filed May 31 , 2012. The contents of these applications are incorporated herein by reference in their entirety.
  • the glass comprises: at least about 50 mol%
  • R2O comprises Na20; AI2O3, wherein -0.5 mol% ⁇ Al 2 0 3 (mol%) - R 2 0(mol%) ⁇ 2 mol%; and B 2 0 3 , and wherein B 2 0 3 (mol%) - (R20(mol%) - Ai203(mol%)) > 4.5 mol%.
  • the glass has a zircon breakdown temperature that is equal to the temperature at which the glass has a viscosity of greater than about 40 kPoise and comprises: at least about 50 mol% SiC ; at least about 10 mol% R2O, wherein R2O comprises a20; AI2O3; and B2O3, wherein B 2 0 3 (mol%) - (R 2 0(mol%) - Al 2 0 3 (mol%)) > 4.5 mol%.
  • the glass is ion exchanged, has a Vickers crack initiation threshold of at least about 30 kgf, and comprises: at least about 50 mol% S1O2; at least about 10 mol% R2O, wherein R 2 0 comprises Na 2 0; AI2O 3 , wherein -0.5 mol% ⁇ Al 2 0 3 (mol%) - R 2 0(mol%) ⁇ 2 mol%; and B 2 0 3 , wherein B 2 0 3 (mol%) - (R 2 0(mol%) - Al 2 0 3 (mol%)) > 4.5 mol%.
  • Such glasses are described in U.S. Patent Application No. 903,398, by Matthew J.
  • the monovalent and divalent cation oxides are selected from the group consisting of L12O, Na20, K2O, Rb 2 0, CS2O, MgO, CaO, SrO, BaO, and ZnO.
  • the glass comprises 0 mol% B2O 3 .
  • the alkali aluminosilicate glass comprises: from about 50 mol% to about 72 mol% SiC ; from about 12 mol% to about 22 mol% AI2O 3 ; up to about 15 mol% B2O 3 ; up to about 1 mol% P2O5; from about 11 mol% to about 21 mol% Na 2 0; up to about 5 mol% K 2 0; up to about 4 mol% MgO; up to about 5 mol% ZnO; and up to about 2 mol% CaO.
  • the glass comprises: from about 55 mol% to about 62 mol% S1O2; from about 16 mol% to about 20 mol% AI2O 3 ; from about 4 mol% to about 10 mol% B2O 3 ; from about 14 mol% to about 18 mol% a20; from about 0.2 mol% to about 4 mol% K2O; up to about 0.5 mol% MgO; up to about 0.5 mol% ZnO; and up to about 0.5 mol% CaO, wherein the glass is substantially free of P2O5.
  • Na 2 0 + K 2 0 - AI2O 3 ⁇ 2.0 mol% and, in certain embodiments Na 2 0 + K 2 0 - A1 2 0 3 ⁇ 0.5 mol%.
  • B2O3 - ( a20 + K2O - AI2O3) > 4 mol% and, in certain embodiments, B2O 3 - (Na 2 0 + K 2 0 - AI2O 3 ) > 1 mol%.
  • the glasses described herein are substantially free of at least one of arsenic, antimony, barium, strontium, bismuth, and their compounds.
  • the glasses may include up to about 0.5 mol% L12O, or up to about 5 mol% L12O or, in some embodiments, up to about 10 mol% Li 2 0.
  • the glasses described herein when ion exchanged, are resistant to introduction of flaws by sharp or sudden impact. Accordingly, these ion exchanged glasses exhibit Vickers crack initiation threshold of at least about 10 kilogram force (kgf). In certain embodiments, these glasses exhibit a Vickers crack initiation threshold of at least 20 kgf and, in some embodiments, at least about 30 kgf.
  • the glasses described herein may, in some embodiments, be down- drawable by processes known in the art, such as slot-drawing, fusion drawing, redrawing, and the like, and have a liquidus viscosity of at least 130 kilopoise. In addition to those compositions listed hereinabove, various other ion exchangeable alkali aluminosilicate glass compositions may be used.
  • the strengthened glasses described herein are considered suitable for various two- and three-dimensional shapes and may be utilized in various applications, and various thicknesses are contemplated herein.
  • the glass article has a thickness in a range from about 0.1 mm up to about 1.5 mm. In some embodiments, the glass article has a thickness in a range from about 0.1 mm up to about 1.0 mm and, in certain embodiments, from about 0.1 mm up to about 0.5 mm.
  • Strengthened glass articles may also be defined by their central tension.
  • the strengthened glass article has a CT ⁇ 150 MPa, or a CT ⁇ 125 MPa, or CT ⁇ 100 MPa.
  • the central tension of the strengthened glass correlates to the frangible behavior of the strengthened glass article.
  • a method of making a strengthened glass article having at least one compressive stress layer extending from a surface of the strengthened glass article to a depth of compression DOC of at least about 45 ⁇ includes a first ion exchange step in which an alkali aluminosilicate glass article is immersed in a first ion exchange bath at a temperature of greater than 400°C for a time sufficient such that the compressive stress layer has a depth of compression of at least about 45 ⁇ after the first ion exchange step.
  • the immersion times in the first ion exchange bath may depend upon factors such as the temperature and/or composition of the ion exchange bath, the diffusivity of the cations within the glass, and the like. Accordingly, various time periods for ion exchange are contemplated as being suitable. In those instances in which potassium cations from the ion exchange bath are exchanged for sodium cations in the glass, the bath typically comprises potassium nitrate (KNO 3 ).
  • the first ion exchange step in some embodiments, may be conducted for a time of at least 5 hours. Longer ion exchange periods for the first ion exchange step may correlate with larger sodium ion content in the first ion exchange bath.
  • the desired sodium ion content in first ion exchange bath may be achieved, for example, by including at least about 30% by weight or, in some embodiments, at least about 40% by weight of a sodium compound such as sodium nitrate ( a Os) or the like in the first ion exchange bath.
  • a sodium compound such as sodium nitrate ( a Os) or the like in the first ion exchange bath.
  • the sodium compound accounts for about 40% to about 60% by weight of the first ion exchange bath.
  • the first ion exchange step is carried out at a temperature of about 440°C or greater.
  • the strengthened glass article may have a maximum compressive stress (CS) of at least 150 MPa.
  • the strengthened glass article may have a CS of at least 200 MPa after the first ion exchange step, or a CS range of about 200 to about 300 MPa after the first ion exchange step. While the first ion exchange step minimally achieves a compressive layer depth /depth of compression DOC of at least 45 ⁇ , it is contemplated that the compressive stress layer may have a depth of 50 ⁇ to 100 ⁇ and, in some embodiments, 60 ⁇ to 100 ⁇ after the first ion exchange step.
  • a second ion exchange step may be conducted by immersing the alkali aluminosilicate glass article in a second ion exchange bath different from the first ion exchange bath at a temperature of at least 350°C for a time sufficient to produce the shallow steep segment with a depth d a of at least about 3 ⁇ .
  • the second ion exchange step is a relatively rapid ion exchange step that yields a "spike" of compressive stress near the surface of the glass as depicted in FIG. 3.
  • the second ion exchange step may be conducted for a time of up to about 30 minutes or, in other embodiments, up to about 15 minutes or, in some embodiments, in a range from about 10 minutes to about 60 minutes.
  • the second ion exchange step is directed to delivering a different ion to the alkali aluminosilicate glass article than the first ion exchange step.
  • the composition of the second ion exchange bath therefore differs from the first ion exchange bath.
  • the second ion exchange bath comprises at least about 95% by weight of a potassium composition (e.g., KNO3) that delivers potassium ions to the alkali aluminosilicate glass article.
  • the second ion exchange bath may comprise from about 98% to about 99.5% by weight of the potassium composition.
  • the second ion exchange bath may, in further embodiments, comprise up to about 2% by weight, or from about 0.5% to about 1.5% by weight of a sodium composition such as, for example, NaNCh.
  • the temperature of the second ion exchange step may be 390°C or greater.
  • the second ion exchange step may conclude the chemical strengthening procedure.
  • the strengthened glass article may have a compressive stress (CS) of at least about 700 MPa following the second ion exchange step.
  • the strengthened glass article has a maximum compressive stress of about 700 to about 1200 MPa, or about 700 to 1000 MPa after the second ion exchange step. While the second ion exchange step minimally achieves a compressive layer DOL of at least about 70 ⁇ , it is contemplated that the compressive stress layer may have a DOL in a range from about 90 ⁇ to aboutl30 ⁇ after the second ion exchange step.
  • Frangible behavior is characterized by at least one of: breaking of the strengthened glass article (e.g., a plate or sheet) into multiple small pieces (e.g., ⁇ 1 mm); the number of fragments formed per unit area of the glass article; multiple crack branching from an initial crack in the glass article; violent ejection of at least one fragment a specified distance (e.g., about 5 cm, or about 2 inches) from its original location; and combinations of any of the foregoing breaking (size and density), cracking, and ejecting behaviors.
  • the terms "frangible behavior” and “frangibility” refer to those modes of violent or energetic fragmentation of a strengthened glass article absent any external restraints, such as coatings, adhesive layers, or the like. While coatings, adhesive layers, and the like may be used in conjunction with the strengthened glass articles described herein, such external restraints are not used in determining the frangibility or frangible behavior of the glass articles.
  • FIGS. 13a and 13b Examples of frangible behavior and non-frangible behavior of strengthened glass articles upon point impact with a scribe having a sharp tungsten carbide (WC) tip are shown in FIGS. 13a and 13b.
  • the point impact test that is used to determine frangible behavior includes an apparatus that is delivered to the surface of the glass article with a force that is just sufficient to release the internally stored energy present within the strengthened glass article. That is, the point impact force is sufficient to create at least one new crack at the surface of the strengthened glass sheet and extend the crack through the compressive stress CS region (i.e., depth of layer) into the region that is under central tension CT.
  • each ion exchanged glass plate shown in FIGS. 13a and 13b was subjected to a sharp dart indenter (e.g., a scribe with a sharp WC point) contact sufficient to propagate a crack into the inner region of the plate, the inner region being under tensile stress.
  • a sharp dart indenter e.g., a scribe with a sharp WC point
  • the force applied to the glass plate was just sufficient to reach the beginning of the inner region, thus allowing the energy that drives the crack to come from the tensile stresses in the inner region rather than from the force of the dart impact on the outer surface.
  • the degree of ejection may be determined, for example, by centering the glass sample on a grid, impacting the sample and measuring the ejection distance of individual pieces using the grid.
  • glass plate a can be classified as being frangible.
  • glass plate a fragmented into multiple small pieces that were ejected, and exhibited a large degree of crack branching from the initial crack to produce the small pieces. Approximately 50% of the fragments are less than 1mm in size, and it is estimated that about 8 to 10 cracks branched from the initial crack. Glass pieces were also ejected about 5 cm from original glass plate a, as seen in FIG. 14a.
  • a glass article that exhibits any of the three criteria (i.e., multiple crack branching, ejection, and extreme fragmentation) described hereinabove is classified as being frangible. For example, if a glass exhibits excessive branching alone but does not exhibit ejection or extreme fragmentation as described above, the glass is still characterized as frangible.
  • Glass plates b, c, (FIG. 14b) and d (FIG. 14a) are classified as not frangible. In each of these samples, the glass sheet has broken into a small number of large pieces.
  • Glass plate b (FIG. 14) for example, has broken into two large pieces with no crack branching; glass plate c (FIG. 14b) has broken into four pieces with two cracks branching from the initial crack; and glass plate d (FIG. 14a) has broken into four pieces with two cracks branching from the initial crack.
  • samples b, c, and d are classified as non-frangible or substantially non- frangible.
  • a frangibility index (Table 1) can be constructed to quantify the degree of frangible or non-frangible behavior of a glass, glass ceramic, and/or a ceramic article upon impact with another object. Index numbers, ranging from 1 for non-frangible behavior to 5 for highly frangible behavior, have been assigned to describe different levels of frangibility or non- frangibility.
  • frangibility can be characterized in terms of numerous parameters: 1) the percentage of the population of fragments having a diameter (i.e., maximum dimension) of less than 1 mm (“Fragment size” in Table 1); 2) the number of fragments formed per unit area (in this instance, cm 2 ) of the sample ("Fragment density” in Table 1); 3) the number of cracks branching from the initial crack formed upon impact ("Crack branching” in Table 1); and 4) the percentage of the population of fragments that is ejected upon impact more than about 5 cm (or about 2 inches) from their original position ("Ejection” in Table 1).
  • a frangibility index is assigned to a glass article if the article meets at least one of the criteria associated with a particular index value.
  • the article may be assigned a frangibility index range (e.g., a frangibility index of 2-3).
  • the glass article may be assigned the highest value of frangibility index, as determined from the individual criteria listed in Table 1. In many instances, it is not possible to ascertain the values of each of the criteria, such as the fragmentation density or percentage of fragments ejected more than 5 cm from their original position, listed in Table 1.
  • the different criteria are thus considered individual, alternative measures of frangible behavior and the frangibility index such that a glass article falling within one criteria level will be assigned the corresponding degree of frangibility and frangibility index. If the frangibility index based on any of the four criteria listed in Table 1 is 3 or greater, the glass article is classified as frangible.
  • glass plate a fragmented into multiple ejected small pieces and exhibited a large degree of crack branching from the initial crack to produce the small pieces. Approximately 50% of the fragments are less than 1 mm in size and it is estimated that about 8 to 10 cracks branched from the initial crack. Based upon the criteria listed in Table 1 , glass plate a has a frangibility index of between about 4-5, and is classified as having a medium-high degree of frangibility. [00127] A glass article having a frangibility index of less than 3 (low frangibility) may be considered to be non-frangible or substantially non-frangible.
  • Glass plates b, c, and d each lack fragments having a diameter of less than 1 mm, multiple branching from the initial crack formed upon impact and fragments ejected more than 5 cm from their original position. Glass plates b, c, and d are non-frangible and thus have a frangibility index of 1 (not frangible).
  • the strengthened glass articles described herein exhibit a frangibility index of less than 3 when subjected to a point impact sufficient to break the strengthened glass article.
  • non- frangible strengthened glass articles may achieve a frangibility index less than 2 or less than 1.
  • IBoS inverted ball on sandpaper
  • FIG. 15b An inverted ball on sandpaper test is a dynamic component level test that mimics the dominant mechanism for failure due to damage introduction plus bending that typically occurs in strengthened glass articles that are used in mobile or hand held electronic devices, as schematically shown in FIG. 15b.
  • damage introduction (a in FIG. 15b) occurs on the top surface of the glass.
  • Fracture initiates on the top surface of the glass and damage either penetrates the compressive layer (b in FIG. 15b) or the fracture propagates from bending on the top surface or from center tension (c in FIG. 15b).
  • the IBoS test is designed to simultaneously introduce damage to the surface of the glass and apply bending under dynamic load.
  • Apparatus 200 includes a test stand 210 and a ball 230.
  • Ball 230 is a rigid or solid ball such as, for example, a stainless steel ball, or the like. In one embodiment, ball 230 is a 4.2 gram stainless steel ball having diameter of 10 mm. The ball 230 is dropped directly onto the glass sample 218 from a predetermined height h.
  • Test stand 210 includes a solid base 212 comprising a hard, rigid material such as granite or the like.
  • a sheet 214 having an abrasive material disposed on a surface of the sheet is placed on the upper surface of the solid base 212 such that surface with the abrasive material faces upward.
  • sheet 214 is sand paper having a 30 grit surface and, in other embodiments, a 180 grit surface.
  • Glass sample 218 is held in place above sheet 214 by sample holder 215 such that an air gap 216 exists between glass sample 218 and sheet 214.
  • the air gap 216 between sheet 214 and glass sample 218 allows the glass sample 218 to bend upon impact by ball 230 and onto the abrasive surface of sheet 214.
  • the glass sample 218 is clamped across all corners to keep bending contained only to the point of ball impact and to ensure repeatability.
  • sample holder 214 and test stand 210 are adapted to accommodate sample thicknesses of up to about 2 mm.
  • the air gap 216 is in a range from about 50 ⁇ to about 100 ⁇ .
  • An adhesive tape 220 may be used to cover the upper surface of the glass sample to collect fragments in the event of fracture of the glass sample upon impact of ball 230.
  • the abrasive surface is sandpaper, such as silicon carbide or alumina sandpaper, engineered sandpaper, or any abrasive material known to one ordinary skilled in the art for having comparable hardness and/or sharpness.
  • sandpaper having 180 grit and an average grit particle size ranging from about 70 ⁇ to about 90 ⁇ may be used, as it has a known range of particle sharpness, a surface topography more consistent than concrete or asphalt, and a particle size and sharpness that produces the desired level of specimen surface damage.
  • 180 grit sandpaper that may be used in the drop tests described herein is Rhynowet® 180 grit sandpaper produced by Indasa.
  • a method 300 of conducting the IBoS test in the apparatus 200 described hereinabove is shown in FIG. 15c.
  • Step 310 a glass sample (218 in FIG. 15a) is placed in the test stand 210, described previously and secured in sample holder 215 such that an air gap 216 is formed between the glass sample 218 and sheet 214 with an abrasive surface.
  • Method 300 presumes that the sheet 214 with an abrasive surface has already been placed in test stand 210. In some embodiments, however, the method may include placing sheet 214 in test stand 210 such that the surface with abrasive material faces upward.
  • an adhesive tape 220 is applied to the upper surface of the glass sample 218 prior to securing the glass sample 218 in the sample holder 210.
  • Step 320 a solid ball 230 of predetermined mass and size is dropped from a predetermined height h onto the upper surface of the glass sample 218, such that the ball 230 impacts the upper surface (or adhesive tape 220 affixed to the upper surface) at approximately the center (i.e., within 1 mm, or within 3 mm, or within 5 mm, or within 10 mm of the center) of the upper surface.
  • the extent of damage to the glass sample 218 is determined (Step 330).
  • the term "fracture” means that a crack propagates across the entire thickness and/or entire surface of a substrate when that substrate is dropped or impacted by an object.
  • the sheet 218 with the abrasive surface may be replaced after each drop to avoid "aging" effects that have been observed in repeated use of other types (e.g., concrete or asphalt) drop test surfaces.
  • test 300 Various predetermined drop heights h and increments are typically used in test 300.
  • the test may, for example, utilize a minimum drop height to start (e.g., about 10-20 cm). The height may then be increased for successive drops by either a set increment or variable increments.
  • the test 300 is stopped once the glass sample 218 breaks (331 in FIG,. 15c). Alternatively, if the drop height h reaches the maximum drop height (e.g., about 220 cm) without glass fracture, the drop test 300 may also be stopped, or the glass sample 218 may be repeatedly dropped from that maximum height until fracture occurs.
  • the maximum drop height e.g., about 220 cm
  • IBoS test 300 is performed only once on each glass sample 218 at each predetermined height h. In other embodiments, however, each sample may be subjected to multiple tests at each height.
  • Step 340 If no fracture resulting from the ball drop at the predetermined drop height is observed (332 in FIG. 2), the drop height is increased by a predetermined increment (Step 334) - such as, for example 5, 10, or 20 cm - and Steps 320 and 330 are repeated until either sample fracture is observed (331) or the maximum test height is reached (336) without sample fracture. When either Step 331 or 336 is reached, the test 300 is ended.
  • the strengthened glasses described hereinabove have at least about a
  • the survival rate of the strengthened glasses dropped 100 cm in the IBoS test is at least about 70%, in other embodiments, at least about 80%, and, in still other embodiments, at least about 90%.
  • the survival rate of the strengthened glasses dropped 180 cm in the IBoS test is at least about 60%, in other embodiments, at least about 70%, in still other embodiments, at least about 80%, and, in other embodiments, at least about 90%.
  • the survivability rate of the strengthened glass article when dropped from a predetermined height using the IBoS test method and apparatus described hereinabove at least five identical samples (i.e., composition and approximately the same CS and DOC or DOL) of the strengthened glass are tested, although larger numbers (e.g., 10, 20, 30, etc.) of samples may be subjected to testing.
  • Each sample is dropped a single time from the predetermined height (e.g., 100 cm) and visually (i.e., with the naked eye) examined for evidence of fracture (crack formation and propagation across the entire thickness and/or entire surface of a sample.
  • a sample is deemed to have "survived" the drop test if no fracture is observed after being dropped.
  • the survivability rate is determined to be the percentage of the sample population that survived the drop test. For example, if 7 samples out of a group of 10 did not fracture when dropped, the survivability rate would be 70%.
  • the strengthened glass articles described herein demonstrate improved surface strength, when subjected to abraded ring-on-ring (AROR).
  • Strength of a material is defined as the stress at which fracture occurs.
  • Abraded ring-on-ring is a surface strength measurement for testing flat glass specimens, and ASTM C1499- 09(2013), entitled “Standard Test Method for Monotonic Equibiaxial Flexural Strength of Advanced Ceramics at Ambient Temperature,” serves as the basis for the ring-on-ring abraded ROR test methodology described herein.
  • ASTM C1499-09 are incorporated herein by reference in their entirety.
  • a glass specimen having at least one abraded surface is placed between two concentric rings of differing size to determine equibiaxial flexural strength (i.e., the maximum stress that a material is capable of sustaining when subjected to flexure between two concentric rings), as schematically shown in FIG. 19.
  • the glass specimen is abraded with 90 grit silicon carbide (SiC) particles that are delivered to the glass sample.
  • SiC silicon carbide
  • abraded ring-on-ring configuration 400 the abraded glass specimen 410 is supported by a support ring 420 having a diameter D2.
  • a force F is applied by a load cell (not shown) to the surface of the glass specimen by a loading ring 430 having a diameter Di.
  • the ratio of diameters of the loading ring and support ring D1/D2 may be between 0.2 and 0.5. In some embodiments, Di/D 2 is about 0.5. Loading and support rings 430, 420 should be aligned concentrically to within 0.5% of support ring diameter D2.
  • the load cell used for testing should be accurate to within ⁇ 1% at any load within a selected range. In some embodiments, testing is carried out at a temperature of 23 ⁇ 2°C and a relative humidity of 40 ⁇ 10%.
  • the radius r of the protruding surface of the loading ring 430 h/2 ⁇ r ⁇ 3h/2, where h is the thickness of specimen 410.
  • Loading and support rings 430, 420 are typically made of hardened steel with hardness HR C > 40. ROR fixtures are commercially available.
  • the intended failure mechanism for the ROR test is to observe fracture of the specimen 410 originating from the surface 430a within the loading ring 430. Failures that occur outside of this region - i.e., between the loading rings 430 and support rings 420 - are omitted from data analysis. Due to the thinness and high strength of the glass specimen 410, however, large deflections that exceed 1 ⁇ 2 of the specimen thickness h are sometimes observed. It is therefore not uncommon to observe a high percentage of failures originating from underneath the loading ring 430. Stress cannot be accurately calculated without knowledge of stress development both inside and under the ring (collected via strain gauge analysis) and the origin of failure in each specimen. AROR testing therefore focuses on peak load at failure as the measured response.
  • the strength of glass depends on the presence of surface flaws. However, the likelihood of a flaw of a given size being present cannot be precisely predicted, as the strength of glass is statistical in nature. A Weibull probability distribution is therefore generally used for the statistical representation of data.
  • the strengthened glass described herein has a surface or equibiaxial flexural strength of at least 10 kgf as determined by abraded ring-on-ring testing. In other embodiments, the surface strength is at least 20 kgf, and in still other embodiments, at least 30 kgf.
  • a plot of AROR data as a function of sample thickness for two strengthened alkali aluminosilicate glasses is shown in FIG. 20.
  • Strengthened glass A which is described in U.S. Patent Application No. 13/305,271 , exhibits a compressive stress profile shown in FIG. 3 resulting from a two-step ion exchange process described herein, whereas strengthened glass B, which is described in U.S. Patent Application No. 13/903,433, does not exhibit the compressive stress profile shown in FIG. 3.
  • the two step ion exchange process results in higher surface strength as determined by AROR measurements.
  • Sample a was ion exchanged at 440°C for 9 hours in a molten salt bath containing 52% NaN0 3 and 48% KN0 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 4a shows TE (1) and TM (2) index profiles determined from the mode spectra
  • FIG. 4b shows the compressive stress profile.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample a were determined to be 232 MPa and 63 ⁇ , respectively.
  • Sample b was ion exchanged at 440°C for 10 hours in a molten salt bath containing 52% NaN0 3 and 48% K 0 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 5 a shows TE (1) and TM (2) index profiles determined from the mode spectra
  • FIG. 5b shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample b were determined to be 232 MPa and 65 ⁇ , respectively.
  • FIG. 5c shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a first linear segment A extending from the surface of the glass (0 ⁇ depth) to the beginning of a transition region C at about 8 ⁇ and a second linear segment B extending from the end of the transition region C at about 16 ⁇ .
  • the compressive stress profile shown in FIG. 5c is analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface of the sample and the depth of compression were determined to be 852 MPa and 61 ⁇ , respectively.
  • the slope of segment B of the stress profile is approximately 3.75 MPa/um, whereas the slope of segment B was 89 MPa/um.
  • the transition region C from slope A to slope B ranged from a depth of about 9 ⁇ to about 14 ⁇ .
  • Sample c was ion exchanged at 440°C for 1 1.25 hours in a molten salt bath containing 52% a C and 48% K O 3 by weight. Following ion exchange, the TE and TM index profiles determined from the mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 6a shows TE (1) and TM (2) mode spectra
  • FIG. 6b shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample c were determined to be 227 MPa and 67 ⁇ , respectively. ii) 0.5 mm Thickness
  • Sample d was ion exchanged at 440°C for 5.8 hours in a molten salt bath containing 37% a 0 3 and 63% K O 3 by weight.
  • the TE and TM index profiles determined from the mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 7a shows TE (1) and TM (2) mode spectra
  • FIG. 7b shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample d were determined to be 255 MPa and 57 ⁇ , respectively.
  • Sample e was ion exchanged at 440°C for 8.3 hours in a molten salt bath containing 37% a C and 63% K O 3 by weight. Following ion exchange, the TE and TM index profiles determined from the mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 8a shows the TE (1) and TM (2) mode spectra
  • FIG. 8b shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample e were determined to be 243 MPa and 66 ⁇ , respectively. iii 0.55 mm Thickness
  • Sample k was first ion exchanged at 450°C for 7.75 hours in a molten salt bath containing approximately 40% NaN(3 ⁇ 4 and 60% KNO 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 13 a shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample k after the first ion exchange were determined to be 268 MPa and 73 ⁇ , respectively.
  • the slope of the linear compressive stress profile was 3.7 MPa/um.
  • FIG. 13b shows the compressive stress profile determined from the mode spectra. Following the second ion exchange, the compressive stress profile had a first linear segment A extending from the surface of the glass to a transition region C at about 8 ⁇ and a second linear segment B extending from the transition region C at about 16 ⁇ to the depth of compression DOC.
  • the compressive stress profile in FIG. 13b is analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface and the depth of compression of sample k after the second ion exchange were determined to be 896 MPa and 70 ⁇ , respectively.
  • the slope portion A remained at approximately 3.7 MPa/um, whereas the slope of portion B was 86 MPa/um.
  • the transition region C ranged from a depth of about 8 ⁇ to about 16 ⁇ . iv) 0.7 mm Thickness
  • Sample f was first ion exchanged at 450°C for 8.5 hours in a molten salt bath containing 45% a C ⁇ and 55% KNO 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 9a shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample f after the first ion exchange were determined to be 281 MPa and 75 ⁇ , respectively.
  • the slope of the linear compressive stress profile was 3.75 MPa/um.
  • FIG. 9b shows the compressive stress profile determined from the mode spectra. Following the second ion exchange, the compressive stress profile had a first linear segment A extending from the surface of the glass to a transition region C at about 7 ⁇ and a second linear segment B extending from the transition region C at about 15 ⁇ to the depth of compression DOC, and is analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface and the depth of compression of sample f after the second ion exchange were determined to be 842 MPa and 72 ⁇ , respectively.
  • the slope portion A remained at approximately 3.75 MPa/um, whereas the slope of portion B was 85 MPa/um.
  • the transition region C ranged from a depth of about 7 ⁇ to about 15 ⁇ . iv) 0.8 mm Thickness
  • FIG. 10a shows the compressive stress profile of sample g determined from the mode spectra following the first ion exchange.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample g after the first ion exchange were determined to be 358 MPa and 72 ⁇ , respectively.
  • the slope of the linear compressive stress profile was 5.1 MPa/um.
  • FIG. 10b shows the compressive stress profile determined from the mode spectra. Following the second ion exchange, the compressive stress profile had a first linear segment or portion A extending from the surface of the glass to a transition region and a second linear segment B extending from a transition region C to the depth of compression DOC. This is analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface and the depth of compression of sample g after the second ion exchange were determined to be 861 MPa and 70 ⁇ , respectively.
  • the slope portion B was 4.65 MPa/um, whereas the slope of portion A was 78 MPa/um.
  • the transition region C from slope A to slope B occurred over a range of depths from about 7 ⁇ to about 12 ⁇ .
  • sample h was subjected to a second ion exchange at 319°C for 24 minutes in a molten salt bath containing 1% aN03 and 99% KNO3 by weight.
  • the compressive stress profile had a first linear segment A extending from the surface of the glass to a depth of about 5 ⁇ and a second linear segment B extending from the upper boundary of a transition region C at a depth of about 15 ⁇ to a depth of 70 ⁇ .
  • the two segment profile is analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface and the depth of compression of sample g after the second ion exchange were determined to be 877 MPa and 70 ⁇ , respectively.
  • the slope of segment B was about 5 MPa/um, whereas the slope of portion a was 52 MPa/um.
  • the transition region C from slope A to slope B occurred over a range of depths from about 8 ⁇ to about 15 ⁇ .
  • Sample 1 was first ion exchanged at 450°C for 48 hours in a molten salt bath containing 69% a C ⁇ and 31% K O 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 16 shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample 1 after the first ion exchange were determined to be 146 MPa and 142 ⁇ , respectively.
  • the slope of the linear compressive stress profile was 1.03 MPa/um.
  • FIG. 17 shows the compressive stress profile determined from the mode spectra.
  • the compressive stress profile has a single linear portion analogous to that shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample m after the first ion exchange were determined to be 140 MPa and 153 ⁇ , respectively.
  • the slope of the linear compressive stress profile was 0.904 MPa/um.
  • Sample i was first ion exchanged at approximately 450°C for about 7.5 hours in a molten salt bath containing 38% a C and 62% KNO 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. l ib shows the compressive stress profile determined from the mode spectra. Following the second ion exchange, the compressive stress profile had a first linear portion A and a second linear portion B, analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface and the depth of compression of sample h after the second ion exchange were determined to be 746 MPa and 73 ⁇ , respectively.
  • the slope of portion A was approximately 52 MPa/um, whereas the slope of portion B was about 4 MPa/um.
  • Sample j was first ion exchanged at 440°C for 1 1 hours in a molten salt bath containing 37% a C ⁇ and 63% K O 3 by weight. Following ion exchange, the TE and TM mode spectra were measured and the compressive stress profile was determined therefrom.
  • FIG. 12a shows the compressive stress profile of sample j determined from the mode spectra following the first ion exchange.
  • the compressive stress profile has a single linear segment analogous to the stress profile shown in FIG. 2.
  • the compressive stress CS at the surface and the depth of compression of sample j after the first ion exchange were determined to be 359 MPa and 82 ⁇ , respectively.
  • the slope of the linear compressive stress profile was 5.3 MPa/um.
  • FIG. 12b shows the compressive stress profile determined from the mode spectra. Following the second ion exchange, the compressive stress profile had a first linear segment A extending from the surface of the glass to the beginning of a transition region C at about 8 ⁇ and a second linear segment B extending from the end of transition region C at about 16 ⁇ to the depth of compression DOC. This behavior is analogous to the stress profile schematically shown in FIG. 3.
  • the compressive stress CS at the surface and the depth of compression of sample j after the second ion exchange were determined to be 860 MPa and 80 ⁇ , respectively.
  • the slope portion A remained at approximately 5.3 MPa/um, whereas the slope of portion B was 73 MPa/um.
  • the transition region C from slope A to slope B occurred over a range of depths from about 8 ⁇ and about 16 ⁇ .
  • IBoS inverted ball drop on sandpaper
  • Samples A and E are alkali aluminosilicate glasses of identical composition, described in U.S. Patent Application No. 13/305,271, cited above.
  • Samples B and F are commercially available alkali aluminosilicate glasses (Dragontrail® Glass, manufactured by Asahi Glass Company) of identical composition. Sample B was ion exchanged, and had a depth of layer of 26.1 ⁇ and a surface compressive stress of 795 MP, whereas Sample F was not ion exchanged.
  • Sample C is ion exchanged soda lime glass (SLG).
  • Samples D and G are alkali aluminosilicate glasses of identical composition, described in U.S. Patent Application No. 13/903,433, cited above. Sample D was ion exchanged, and had a depth of layer of 42.1 ⁇ and a surface compressive stress of 871 MP, whereas Sample G was not ion exchanged.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Physics & Mathematics (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Surface Treatment Of Glass (AREA)
  • Devices For Indicating Variable Information By Combining Individual Elements (AREA)
  • Glass Compositions (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
PCT/US2015/041976 2014-07-25 2015-07-24 Strengthened glass with deep depth of compression Ceased WO2016014937A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
CN201580040362.6A CN107108345B (zh) 2014-07-25 2015-07-24 具有深的压缩深度的强化玻璃
KR1020177005323A KR20170036067A (ko) 2014-07-25 2015-07-24 깊은 압축의 깊이를 갖는 강화 유리
EP15750515.7A EP3169639B1 (en) 2014-07-25 2015-07-24 Strengthened glass with deep depth of compression
DK15750515.7T DK3169639T3 (da) 2014-07-25 2015-07-24 Forstærket glas med dyb kompressionsdybde
CN202310075381.9A CN116282965A (zh) 2014-07-25 2015-07-24 具有深的压缩深度的强化玻璃
JP2017502188A JP2017527513A (ja) 2014-07-25 2015-07-24 圧縮深さが深い強化ガラス
KR1020207011705A KR20200045575A (ko) 2014-07-25 2015-07-24 깊은 압축의 깊이를 갖는 강화 유리

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201462029075P 2014-07-25 2014-07-25
US62/029,075 2014-07-25

Publications (1)

Publication Number Publication Date
WO2016014937A1 true WO2016014937A1 (en) 2016-01-28

Family

ID=53836826

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2015/041976 Ceased WO2016014937A1 (en) 2014-07-25 2015-07-24 Strengthened glass with deep depth of compression

Country Status (6)

Country Link
EP (1) EP3169639B1 (enExample)
JP (2) JP2017527513A (enExample)
KR (2) KR20170036067A (enExample)
CN (3) CN108609866B (enExample)
DK (1) DK3169639T3 (enExample)
WO (1) WO2016014937A1 (enExample)

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2016070048A1 (en) 2014-10-31 2016-05-06 Corning Incorporated Strengthened glass with ultra-deep depth of compression
WO2016073539A1 (en) 2014-11-04 2016-05-12 Corning Incorporated Deep non-frangible stress profiles and methods of making
US9593042B2 (en) 2014-10-08 2017-03-14 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
WO2017177109A1 (en) * 2016-04-08 2017-10-12 Corning Incorporated Glass-based articles including a stress profile comprising two regions, and methods of making
US9908811B2 (en) 2015-12-11 2018-03-06 Corning Incorporated Fusion formable glass-based articles including a metal oxide concentration gradient
US10017417B2 (en) 2016-04-08 2018-07-10 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
KR20190020028A (ko) * 2016-06-14 2019-02-27 코닝 인코포레이티드 향상된 낙하 성능을 갖는 유리
WO2019079400A1 (en) * 2017-10-17 2019-04-25 PGBC Intellectual Holdings, LLC NOVEL PARADIGMS OF CHEMICALLY REINFORCED THIN-GLASS SUBSTRATES FOR MODIFIED CURVATURE AND METHODS OF MAKING
CN110234616A (zh) * 2017-02-07 2019-09-13 Agc株式会社 化学强化玻璃
US10579106B2 (en) 2015-07-21 2020-03-03 Corning Incorporated Glass articles exhibiting improved fracture performance
US10611681B2 (en) 2015-12-08 2020-04-07 Corning Incorporated S-shaped stress profiles and methods of making
EP3838860A1 (en) * 2019-12-20 2021-06-23 Samsung Display Co., Ltd. Glass article and display device including the same
CN113480197A (zh) * 2021-08-02 2021-10-08 四川虹科创新科技有限公司 锂硅酸盐玻璃的强化工艺和强化玻璃
US11492291B2 (en) 2012-02-29 2022-11-08 Corning Incorporated Ion exchanged glasses via non-error function compressive stress profiles
US11613103B2 (en) 2015-07-21 2023-03-28 Corning Incorporated Glass articles exhibiting improved fracture performance
US11634359B2 (en) 2014-02-24 2023-04-25 Corning Incorporated Strengthened glass with deep depth of compression
US11795103B2 (en) 2017-10-17 2023-10-24 PGBC Intellectual Holdings, LLC Chemically-strengthened thin glass substrates new paradigms for modified curvature and methods of manufacture
US11878941B2 (en) 2014-06-19 2024-01-23 Corning Incorporated Glasses having non-frangible stress profiles

Families Citing this family (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11691911B2 (en) 2017-04-13 2023-07-04 Samsung Display Co., Ltd. Reinforced window member and method of manufacturing the same
CN110002733A (zh) * 2018-01-05 2019-07-12 南昌欧菲光学技术有限公司 微晶玻璃的强化方法及微晶玻璃盖板的制作方法
JP2019123658A (ja) * 2018-01-19 2019-07-25 Agc株式会社 化学強化ガラスの製造方法および化学強化ガラス
KR102732612B1 (ko) * 2018-10-09 2024-11-21 니폰 덴키 가라스 가부시키가이샤 강화 유리 및 강화 유리의 제조 방법
DE112018008220T5 (de) * 2018-12-21 2021-09-02 Ohara Inc. Kristallisiertes glassubstrat
KR102150391B1 (ko) * 2019-06-12 2020-09-02 (주)유티아이 폴딩부가 형성된 플렉시블 커버 윈도우 및 폴딩부가 형성된 플렉시블 커버 윈도우의 제조방법
CN110160866B (zh) * 2019-06-20 2024-02-06 四川大学 一种ring-on-ring双轴弯曲强度测试夹具及其定位盖
US12240780B2 (en) * 2019-07-02 2025-03-04 Corning Incorporated Glass-based articles with stress profiles having regions of enhanced stress
CN110627378B (zh) * 2019-10-15 2022-03-22 Oppo广东移动通信有限公司 玻璃及其制备方法、壳体组件和电子设备
KR102685221B1 (ko) * 2019-12-16 2024-07-16 삼성디스플레이 주식회사 유리 제품 및 이를 포함하는 디스플레이 장치
KR102816247B1 (ko) 2019-12-17 2025-06-04 삼성디스플레이 주식회사 유리 제품 및 그 제조 방법
TW202146349A (zh) * 2020-03-25 2021-12-16 日商安瀚視特控股股份有限公司 覆蓋玻璃
TW202142515A (zh) * 2020-03-25 2021-11-16 日商安瀚視特控股股份有限公司 使用雙離子交換之覆蓋玻璃強化
KR102815052B1 (ko) 2020-04-13 2025-05-30 삼성디스플레이 주식회사 유리 제품 및 이를 포함하는 디스플레이 장치
US11434167B2 (en) * 2020-05-15 2022-09-06 Corning Incorporated Strengthened glass articles and methods of forming the same
TW202210439A (zh) * 2020-07-30 2022-03-16 日商安瀚視特控股股份有限公司 化學離子交換玻璃
US20250263324A1 (en) 2022-04-27 2025-08-21 Nippon Electric Glass Co., Ltd. Reinforced glass plate, method for manufacturing reinforced glass plate, and glass plate to be reinforced
CN117292612A (zh) * 2023-09-08 2023-12-26 昆山国显光电有限公司 盖板及显示面板

Citations (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3798013A (en) * 1971-04-26 1974-03-19 Nippon Sheet Glass Co Ltd Double ion exchange method for strengthening glass articles
US20050250639A1 (en) * 2004-05-07 2005-11-10 Friedrich Siebers Lithium-aluminosilicate flat float glass
US20070060465A1 (en) * 2005-09-12 2007-03-15 Saxon Glass Technologies, Inc. Chemically strengthened lithium aluminosilicate glass having high strength effective to resist fracture upon flexing from impact of high velocity projectiles
US20100028607A1 (en) * 2008-07-29 2010-02-04 Christopher Morton Lee Dual stage ion exchange for chemical strengthening of glass
US20110294649A1 (en) * 2010-05-27 2011-12-01 Sinue Gomez Glasses having low softening temperatures and high toughness
US20120052271A1 (en) * 2010-08-26 2012-03-01 Sinue Gomez Two-step method for strengthening glass
US8158543B2 (en) 2008-02-26 2012-04-17 Corning Incorporated Fining agents for silicate glasses
WO2012126394A1 (en) * 2011-03-23 2012-09-27 Schott Glass Technologies (Suzhou) Co. Ltd. AN ALUMINOSILICATE GLASS CONTAINING Li2O AND P2O5 USED FOR CHEMICAL TOUGHENING
US20130224492A1 (en) * 2012-02-29 2013-08-29 Corning Incorporated Ion exchanged glasses via non-error function compressive stress profiles
US8561429B2 (en) 2008-07-11 2013-10-22 Corning Incorporated Glass with compressive surface for consumer applications
US8586492B2 (en) 2009-08-21 2013-11-19 Corning Incorporated Crack and scratch resistant glass and enclosures made therefrom
US8652978B2 (en) 2007-11-29 2014-02-18 Corning Incorporated Glasses having improved toughness and scratch resistance
WO2015195465A1 (en) 2014-06-19 2015-12-23 Corning Incorporated Glasses having non-frangible stress profiles

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3433611A (en) * 1965-09-09 1969-03-18 Ppg Industries Inc Strengthening glass by multiple alkali ion exchange
FR2808474B3 (fr) * 2000-05-03 2002-05-31 Saint Gobain Vitrage Vitrage feuillete a proprietes de resistance mecanique et d'isolation acoustique
JP4535692B2 (ja) * 2003-05-28 2010-09-01 セントラル硝子株式会社 化学強化ガラス
DE102010009584B4 (de) * 2010-02-26 2015-01-08 Schott Ag Chemisch vorgespanntes Glas, Verfahren zu seiner Herstellung sowie Verwendung desselben
KR101895086B1 (ko) * 2010-09-14 2018-09-04 코닝 인코포레이티드 가정 기기 패시어 및 그의 장착
JP5834793B2 (ja) * 2010-12-24 2015-12-24 旭硝子株式会社 化学強化ガラスの製造方法
EP2762461B1 (en) * 2011-09-29 2018-11-21 Central Glass Company, Limited Chemically strengthened glass and method for producing same
US9206079B2 (en) * 2011-09-29 2015-12-08 Central Glass Company, Limited Chemically strengthened glass plate and method for manufacturing same
US9850162B2 (en) * 2012-02-29 2017-12-26 Corning Incorporated Glass packaging ensuring container integrity

Patent Citations (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3798013A (en) * 1971-04-26 1974-03-19 Nippon Sheet Glass Co Ltd Double ion exchange method for strengthening glass articles
US20050250639A1 (en) * 2004-05-07 2005-11-10 Friedrich Siebers Lithium-aluminosilicate flat float glass
US20070060465A1 (en) * 2005-09-12 2007-03-15 Saxon Glass Technologies, Inc. Chemically strengthened lithium aluminosilicate glass having high strength effective to resist fracture upon flexing from impact of high velocity projectiles
US8652978B2 (en) 2007-11-29 2014-02-18 Corning Incorporated Glasses having improved toughness and scratch resistance
US8623776B2 (en) 2008-02-26 2014-01-07 Corning Incorporated Silicate glasses having low seed concentration
US8158543B2 (en) 2008-02-26 2012-04-17 Corning Incorporated Fining agents for silicate glasses
US8431502B2 (en) 2008-02-26 2013-04-30 Corning Incorporated Silicate glasses having low seed concentration
US8561429B2 (en) 2008-07-11 2013-10-22 Corning Incorporated Glass with compressive surface for consumer applications
US20100028607A1 (en) * 2008-07-29 2010-02-04 Christopher Morton Lee Dual stage ion exchange for chemical strengthening of glass
US8312739B2 (en) 2008-07-29 2012-11-20 Corning Incorporated Dual stage ion exchange for chemical strengthening of glass
US8586492B2 (en) 2009-08-21 2013-11-19 Corning Incorporated Crack and scratch resistant glass and enclosures made therefrom
US20110294649A1 (en) * 2010-05-27 2011-12-01 Sinue Gomez Glasses having low softening temperatures and high toughness
US20120052271A1 (en) * 2010-08-26 2012-03-01 Sinue Gomez Two-step method for strengthening glass
WO2012126394A1 (en) * 2011-03-23 2012-09-27 Schott Glass Technologies (Suzhou) Co. Ltd. AN ALUMINOSILICATE GLASS CONTAINING Li2O AND P2O5 USED FOR CHEMICAL TOUGHENING
US20130224492A1 (en) * 2012-02-29 2013-08-29 Corning Incorporated Ion exchanged glasses via non-error function compressive stress profiles
WO2015195465A1 (en) 2014-06-19 2015-12-23 Corning Incorporated Glasses having non-frangible stress profiles

Cited By (65)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11492291B2 (en) 2012-02-29 2022-11-08 Corning Incorporated Ion exchanged glasses via non-error function compressive stress profiles
US11634359B2 (en) 2014-02-24 2023-04-25 Corning Incorporated Strengthened glass with deep depth of compression
US11878941B2 (en) 2014-06-19 2024-01-23 Corning Incorporated Glasses having non-frangible stress profiles
US12297145B2 (en) 2014-06-19 2025-05-13 Corning Incorporated Glasses having non-frangible stress profiles
US10294151B2 (en) 2014-10-08 2019-05-21 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US10364182B2 (en) 2014-10-08 2019-07-30 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US12187639B2 (en) 2014-10-08 2025-01-07 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US10730791B2 (en) 2014-10-08 2020-08-04 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US10259746B2 (en) 2014-10-08 2019-04-16 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US10266447B2 (en) 2014-10-08 2019-04-23 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US11220456B2 (en) 2014-10-08 2022-01-11 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US11465937B2 (en) 2014-10-08 2022-10-11 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US10532947B2 (en) 2014-10-08 2020-01-14 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US11459270B2 (en) 2014-10-08 2022-10-04 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US9593042B2 (en) 2014-10-08 2017-03-14 Corning Incorporated Glasses and glass ceramics including a metal oxide concentration gradient
US11746046B2 (en) 2014-10-31 2023-09-05 Corning Incorporated Strengthened glass with ultra deep depth of compression
EP3733620A1 (en) * 2014-10-31 2020-11-04 Corning Incorporated Strengthened glass with ultra-deep depth of compression
US11084756B2 (en) 2014-10-31 2021-08-10 Corning Incorporated Strengthened glass with ultra deep depth of compression
WO2016070048A1 (en) 2014-10-31 2016-05-06 Corning Incorporated Strengthened glass with ultra-deep depth of compression
EP3157882B1 (en) * 2014-10-31 2020-08-05 Corning Incorporated Strengthened glass with ultra-deep depth of compression
EP3215471B1 (en) * 2014-11-04 2021-12-15 Corning Incorporated Deep non-frangible stress profiles and methods of making
US11377388B2 (en) 2014-11-04 2022-07-05 Corning Incorporated Deep non-frangible stress profiles and methods of making
US11021393B2 (en) 2014-11-04 2021-06-01 Corning Incorporated Deep non-frangible stress profiles and methods of making
WO2016073539A1 (en) 2014-11-04 2016-05-12 Corning Incorporated Deep non-frangible stress profiles and methods of making
US11613103B2 (en) 2015-07-21 2023-03-28 Corning Incorporated Glass articles exhibiting improved fracture performance
US10579106B2 (en) 2015-07-21 2020-03-03 Corning Incorporated Glass articles exhibiting improved fracture performance
US11267228B2 (en) 2015-07-21 2022-03-08 Corning Incorporated Glass articles exhibiting improved fracture performance
US10611681B2 (en) 2015-12-08 2020-04-07 Corning Incorporated S-shaped stress profiles and methods of making
US11584684B2 (en) 2015-12-08 2023-02-21 Corning Incorporated S-shaped stress profiles and methods of making
US12071369B2 (en) 2015-12-08 2024-08-27 Corning Incorporated S-shaped stress profiles and methods of making
US10787387B2 (en) 2015-12-11 2020-09-29 Corning Incorporated Fusion-formable glass-based articles including a metal oxide concentration gradient
US11472734B2 (en) 2015-12-11 2022-10-18 Corning Incorporated Fusion-formable glass-based articles including a metal oxide concentration gradient
US11878936B2 (en) 2015-12-11 2024-01-23 Corning Incorporated Fusion-formable glass-based articles including a metal oxide concentration gradient
US9908811B2 (en) 2015-12-11 2018-03-06 Corning Incorporated Fusion formable glass-based articles including a metal oxide concentration gradient
US12297141B2 (en) 2015-12-11 2025-05-13 Corning Incorporated Fusion-formable glass-based articles including a metal oxide concentration gradient
US11174197B2 (en) 2016-04-08 2021-11-16 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
US11963320B2 (en) 2016-04-08 2024-04-16 Corning Incorporated Glass-based articles including a stress profile comprising two regions
WO2017177109A1 (en) * 2016-04-08 2017-10-12 Corning Incorporated Glass-based articles including a stress profile comprising two regions, and methods of making
CN107265884A (zh) * 2016-04-08 2017-10-20 康宁股份有限公司 具有含两个区域的应力分布的玻璃基制品及其制备方法
JP7645327B2 (ja) 2016-04-08 2025-03-13 コーニング インコーポレイテッド 2つの領域を含む応力プロファイルを含むガラス系物品および製造方法
US10017417B2 (en) 2016-04-08 2018-07-10 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
US12116311B2 (en) 2016-04-08 2024-10-15 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
US11279652B2 (en) 2016-04-08 2022-03-22 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
CN111039578A (zh) * 2016-04-08 2020-04-21 康宁股份有限公司 具有含两个区域的应力分布的玻璃基制品及其制备方法
US10570059B2 (en) 2016-04-08 2020-02-25 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
US10271442B2 (en) 2016-04-08 2019-04-23 Corning Incorporated Glass-based articles including a stress profile comprising two regions, and methods of making
EP4269368A3 (en) * 2016-04-08 2023-11-22 Corning Incorporated Glass-based articles including a stress profile comprising two regions, and methods of making
JP2023164724A (ja) * 2016-04-08 2023-11-10 コーニング インコーポレイテッド 2つの領域を含む応力プロファイルを含むガラス系物品および製造方法
US11691913B2 (en) 2016-04-08 2023-07-04 Corning Incorporated Glass-based articles including a metal oxide concentration gradient
KR20190020028A (ko) * 2016-06-14 2019-02-27 코닝 인코포레이티드 향상된 낙하 성능을 갖는 유리
KR102555402B1 (ko) * 2016-06-14 2023-07-13 코닝 인코포레이티드 향상된 낙하 성능을 갖는 유리
KR102417153B1 (ko) * 2016-06-14 2022-07-05 코닝 인코포레이티드 향상된 낙하 성능을 갖는 유리
KR20220098402A (ko) * 2016-06-14 2022-07-12 코닝 인코포레이티드 향상된 낙하 성능을 갖는 유리
CN110234616A (zh) * 2017-02-07 2019-09-13 Agc株式会社 化学强化玻璃
JPWO2018147288A1 (ja) * 2017-02-07 2019-11-07 Agc株式会社 化学強化ガラス
CN115716715B (zh) * 2017-02-07 2024-09-17 Agc株式会社 化学强化玻璃
CN115716715A (zh) * 2017-02-07 2023-02-28 Agc株式会社 化学强化玻璃
CN112055702A (zh) * 2017-10-17 2020-12-08 Pgbc智能控股有限责任公司 用于改进曲率的化学强化薄玻璃基材新范例及制造方法
US10457586B2 (en) 2017-10-17 2019-10-29 PGBC Intellectual Holdings, LLC Chemically-strengthened thin glass substrates with modified curvature and methods of manufacture
WO2019079400A1 (en) * 2017-10-17 2019-04-25 PGBC Intellectual Holdings, LLC NOVEL PARADIGMS OF CHEMICALLY REINFORCED THIN-GLASS SUBSTRATES FOR MODIFIED CURVATURE AND METHODS OF MAKING
US11795103B2 (en) 2017-10-17 2023-10-24 PGBC Intellectual Holdings, LLC Chemically-strengthened thin glass substrates new paradigms for modified curvature and methods of manufacture
EP3838860A1 (en) * 2019-12-20 2021-06-23 Samsung Display Co., Ltd. Glass article and display device including the same
US11161771B2 (en) 2019-12-20 2021-11-02 Samsung Display Co., Ltd. Glass article and display device including the same
CN113480197A (zh) * 2021-08-02 2021-10-08 四川虹科创新科技有限公司 锂硅酸盐玻璃的强化工艺和强化玻璃
CN113480197B (zh) * 2021-08-02 2023-03-21 四川虹科创新科技有限公司 锂硅酸盐玻璃的强化工艺和强化玻璃

Also Published As

Publication number Publication date
CN116282965A (zh) 2023-06-23
KR20170036067A (ko) 2017-03-31
JP2017527513A (ja) 2017-09-21
CN107108345B (zh) 2023-02-07
DK3169639T3 (da) 2022-01-03
CN108609866B (zh) 2021-12-07
JP2020111504A (ja) 2020-07-27
CN108609866A (zh) 2018-10-02
EP3169639A1 (en) 2017-05-24
EP3169639B1 (en) 2021-11-10
KR20200045575A (ko) 2020-05-04
CN107108345A (zh) 2017-08-29

Similar Documents

Publication Publication Date Title
US11746046B2 (en) Strengthened glass with ultra deep depth of compression
US11634359B2 (en) Strengthened glass with deep depth of compression
EP3169639B1 (en) Strengthened glass with deep depth of compression
WO2015195419A2 (en) Strengthened glass with deep depth of compression
JP2017527513A5 (enExample)
WO2016191676A1 (en) Strengthened glass with deep depth of compression

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15750515

Country of ref document: EP

Kind code of ref document: A1

DPE1 Request for preliminary examination filed after expiration of 19th month from priority date (pct application filed from 20040101)
ENP Entry into the national phase

Ref document number: 2017502188

Country of ref document: JP

Kind code of ref document: A

REEP Request for entry into the european phase

Ref document number: 2015750515

Country of ref document: EP

WWE Wipo information: entry into national phase

Ref document number: 2015750515

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20177005323

Country of ref document: KR

Kind code of ref document: A