Transparent near infrared shielding glass-ceramic

Abstract

To provide an optically transparent glass ceramic material having a crystalline tungsten bronze phase.SOLUTION: An optically transparent glass-ceramic material comprising a glass phase and a crystalline tungsten bronze phase comprising nanoparticles and having the formula MxWO3, wherein M comprises at least one of H, Li, Na, K, Rb, Cs, Ca, Sr, Ba, Zn, Cu, Ag, Sn, Cd, In, Tl, Pb, Bi, Th, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and U, and 0 <x <1. Alumino-silicate and zinc-bismuth-borate glasses including at least one of Sm2O3, Pr2O3, and Er2O3 are also provided.SELECTED DRAWING: None

Description

Priority

[0001] This application claims the benefit of priority under 35 U.S.C. §119 of U.S. Provisional Patent Application No. 62 / 352,602, filed June 21, 2016, and U.S. Provisional Patent Application No. 62 / 351,616, filed June 17, 2016, the contents of each of which are relied upon and incorporated herein by reference in their entirety. [Technical Field]

[0002] The present disclosure relates to glass-ceramic materials. More particularly, the present disclosure relates to optically transparent glass-ceramic materials. Even more particularly, the present disclosure relates to optically transparent glass-ceramic materials having a crystalline tungsten bronze phase. [Background technology]

[0003] Near-infrared (NIR) blocking glasses have been developed to block and / or eliminate wavelengths ranging from 700 to 2500 nm for a variety of applications, including optical filters, lenses, and flat glass for medical, defense, aerospace, and civilian applications.

[0004] Low-emissivity (Low-E) coatings have been developed to minimize the amount of ultraviolet and infrared radiation that can pass through glass without compromising the amount of visible light transmitted. Low-E coatings are typically either sputtered or pyrolyzed coatings. Alternatively, Low-E plastic laminates may be incorporated into the glass substrate. Summary of the Invention [Problem to be solved by the invention]

[0005] To provide a near-infrared (NIR) shield having high transparency in the visible spectrum, thin films, coatings, and composite materials containing nanosized or micro-sized particles of non-stoichiometric tungsten suboxide or doped non-stoichiometric tungsten trioxide (referred to as tungsten bronzes) have been used. However, tungsten bronze films generally require expensive vacuum deposition chambers, have limited mechanical robustness, are susceptible to the effects of oxygen, moisture, and ultraviolet light, all of which reduce the NIR shielding performance of these materials, cause discoloration, and reduce transparency in the visible light range.

Means for Solving the Problems

[0006] In some embodiments, the present disclosure provides an optically transparent glass-ceramic material comprising a glass phase containing at least about 80 wt% silica and a crystalline tungsten bronze phase having the formula M x , WO3, wherein M includes, but is not limited to, at least one of H, Li, Na, K, Rb, Cs, Ca, Sr, Ba, Zn, Cu, Ag, Sn, Cd, In, Tl, Pb, Bi, Th, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and U, and 0 < x < 1. The crystalline tungsten bronze phase includes nanoparticles. The glass-ceramic, in some embodiments, has a low coefficient of thermal expansion (CTE), strong attenuation or blocking of ultraviolet (UV) radiation at wavelengths less than about 360 nm and near-infrared (NIR) radiation at wavelengths ranging from about 70 nm to about 3000 nm. Aluminosilicate and zinc-bismuth-borate glasses containing at least one of Sm2O3, Pr2O3, and Er2O3 are also provided.

[0007] Thus, one aspect of the present disclosure is a silicate glass phase and from about 1 mol% to about 10 mol% of crystalline M, including nanoparticles xA glass ceramic containing a WO3 phase, wherein M is at least one of H, Li, Na, K, Rb, Cs, Ca, Sr, Ba, Zn, Cu, Ag, Sn, Cd, In, Tl, Pb, Bi, Th, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and U, and 0 < x < 1, is provided.

[0008] A second aspect of the present disclosure is a silicate glass phase and crystalline M containing nanoparticles, from about 1 mol% to about 10 mol%. x A glass ceramic containing a WO3 phase, wherein M is at least one alkali metal and 0 < x < 1, is provided.

[0009] In another aspect, an aluminosilicate glass containing SiO2, Al2O3, and at least one of Sm2O3, Pr2O3, and Er2O3, wherein Sm2O3 + Pr2O3 + Er2O3 ≤ 12 mol%, is also provided. The aluminosilicate glass, in some embodiments, further contains at least one alkaline earth oxide and B2O3. The glass, in some embodiments, has a transmittance of less than about 30% at wavelengths between about 1400 nm and about 1600 nm.

[0010] In yet another aspect, a zinc-bismuth borate glass containing ZnO, Bi2O3, B2O3, and at least one of Sm2O3, Pr2O3, and Er2O3, wherein Sm2O3 + Pr2O3 + Er2O3 ≤ 12 mol%, is provided. In some embodiments, the Zn·Bi·borate glass further contains at least one of Na2O and TeO2. These glasses, in some embodiments, have a transmittance of less than about 30% at wavelengths between about 1400 nm and about 1600 nm.

[0011] These and other aspects, advantages, and notable characteristics will become apparent from the following detailed description, the accompanying drawings, and the appended claims. [Brief explanation of the drawings]

[0012] [Figure 1] Plot of absorption versus wavelength for splat-quenched, slow-cooled, and heat-treated glass-ceramic samples. [Figure 2] Plots of spectra for splat-quenched (A), slow-cooled (B), and heat-treated (C) glass-ceramic compositions. [Figure 3] Graph plotting differential scanning calorimetry cooling curves measured on glass-ceramic samples. [Figure 4] Plot of the spectra of glass-ceramics containing different alkali tungsten bronzes [Figure 5] X-ray diffraction profiles of splat-quenched glass-ceramics. [Figure 6] X-ray diffraction profiles of heat-treated glass-ceramics [Figure 7] Flow diagram of a method for infiltrating glass to form a glass-ceramic [Figure 8] A graph plotting the dispersion curve for Glass E listed in Table E. [Figure 9] A graph plotting transmittance for Glass E listed in Table E. [Figure 10] A graph plotting the transmittance for glasses J, K, and L listed in Table F. DETAILED DESCRIPTION OF THE INVENTION

[0013] In the following description, like reference characters refer to like or corresponding parts throughout the several views shown in the drawings. It will also be understood that, unless otherwise specified, terms such as "top," "bottom," "outer," "inner," etc., are words of convenience and should not be considered limiting terms. Furthermore, whenever a group is described as comprising at least one of a group of elements and combinations thereof, it will be understood that the group may comprise, consist essentially of, or consist of any of those listed elements, either individually or in combination with one another. Similarly, whenever a group is described as consisting of at least one of a group of elements and combinations thereof, it will be understood that the group may consist of any of those listed elements, either individually or in combination with one another. Unless otherwise specified, ranges of values, when recited, include both the upper and lower limits of the range, as well as any ranges therebetween. As used herein, nouns refer to "at least one" or "one or more" objects unless otherwise specified. It is also to be understood that the various features disclosed in the specification and in the drawings may be used in any and all combinations.

[0014] As used herein, the term "glass article" is used in the broadest sense to include any object made wholly or partially from glass and / or glass-ceramics, including laminates of conventional glasses with the glasses and glass-ceramics described herein. Unless otherwise specified, all compositions are expressed in mole percent (mol%). The coefficient of thermal expansion (CTE) is 10 -7 The values ​​are expressed in °C / °C and represent values ​​measured over a temperature range of about 20°C to about 300°C unless otherwise specified.

[0015] As used herein, the term "nanoparticle" refers to a particle between about 1 nanometer (nm) and about 1,000 nm in size. As used herein, the term "platelet" refers to a flat or planar crystal. As used herein, the term "nanorod" refers to an elongated crystal having a length of up to about 1,000 nm and an aspect ratio (length / width) of at least 3, and in some embodiments, in the range of about 3 to about 5.

[0016] As used herein, the term "transmittance" refers to external transmittance, taking into account absorption, scattering, and reflection. Fresnel reflections are not subtracted from the transmittance values ​​reported herein.

[0017] Note that the terms "substantially" and "about" may be used herein to express the inherent degree of uncertainty that may result from any quantitative comparison, value, measurement, or other representation. These terms are also used herein to express the extent to which a quantitative representation may vary from the stated standard without resulting in a change in the basic functionality of the subject matter in question. Thus, an "MgO-free" glass is one in which MgO is not actively added or batched into the glass, but may be present in very small amounts (e.g., less than 400 parts per million (ppm), or less than 300 ppm) as a contaminant.

[0018] Compressive stress and depth of layer are measured using means known in the art. Such means include, but are not limited to, surface stress measurement (FSM) using commercially available instruments such as the FSM-6000 manufactured by Orihara Seisakusho (Tokyo, Japan). Surface stress measurement relies on precise measurement of the stress-optical coefficient (SOC), which is related to the birefringence of the glass. SOC is then measured according to a modified version of Procedure C (hereinafter, "Modification") described in ASTM Standard C770-98 (2013), entitled "Standard Test Method for Measurement of Glass Stress-Optical Coefficient," the contents of which are incorporated herein by reference in their entirety. The Modification of Procedure C involves using a glass disk as the test specimen, having a thickness of 5 to 10 mm and a diameter of 12.7 mm. The disk is isotropic and homogeneous, and is cored and drilled, with both surfaces polished and parallel. The Modification also involves calculating the maximum force, F, to be applied to the disk. The force should be sufficient to produce a compressive stress of at least 20 MPa. Fmax is calculated using the formula: Fmax=7.854 D h where Fmax is the maximum force in Newtons, D is the diameter of the disk in millimeters (mm), and h is the thickness of the optical path, also in mm. For each force applied, the stress is calculated using the formula: σ(MPa)=8F / (π·D·h) where F is the force in Newtons, D is the diameter of the disk in millimeters (mm), and h is the thickness of the optical path, also in millimeters.

[0019] Unless otherwise specified, the terms "depth of layer," "DOL," and "FSM_DOL" refer to the depth of the compressive layer as determined by surface stress measurement (FSM) using commercially available instruments such as, but not limited to, an FSM-6000 stress instrument. The compressive depth DOC refers to the depth at which stress is effectively zero in the glass and can be determined from stress profiles obtained using refractive near-field (RNF) and polarimetric methods known in the art. This DOC is typically smaller than the FSM_DOL measured by an FSM instrument for a single ion-exchange process.

[0020] For tempered glass articles in which the compressive stress layer extends to greater depths within the glass, the FSM technique can suffer from contrast issues that affect the observed DOL value. At greater depths within the compressive layer, there may be inadequate contrast between the TE and TM spectra, making it more difficult to calculate the difference between the spectra of the combined optical modes of TM and TE polarization—and accurately determine the DOL. Furthermore, the FSM software analysis cannot determine the compressive stress profile (i.e., the variation of compressive stress as a function of depth within the glass). Furthermore, the FSM technique cannot determine the depth of layers resulting from ion exchange of specific elements in the glass, such as the exchange of sodium with lithium.

[0021] If the DOL is a small fraction r of the thickness t and the refractive index profile has a depth distribution that is reasonably well approximated by a simple linear truncated profile, then the DOL as determined by FSM is a relatively good approximation of the depth of compression (DOC) of the compressed layer. If the DOL is a significant fraction of the thickness, such as DOL ≥ 0.1 t, then the DOC will most likely be significantly smaller than the DOL. For example, in the ideal case of a linear truncated profile, the relationship DOC = DOL (1 - t) holds, where r = DOL / t.

[0022] Alternatively, compressive stress, stress profile, and layer depth may be determined using scattering linear polarimetry (SCALP) techniques known in the art, which allow for non-destructive measurement of surface stress and layer depth.

[0023] Referring generally to the drawings, and particularly to Figure 1, it will be understood that the description is for purposes of describing particular embodiments and is not intended to limit the scope of the disclosure or the appended claims thereto. The drawings are not necessarily drawn to scale, and certain features and certain views of the drawings may be shown exaggerated in scale or schematic form for clarity and conciseness.

[0024] In some embodiments, optically transparent glass-ceramic materials are described herein that include a glass phase containing at least about 90% by weight of silica and a crystalline tungsten bronze phase. These glass-ceramics include a silicate glass phase and a crystalline tungsten bronze phase. x and about 0.1 mol % to about 10 mol %, or about 1 mol % to about 4 mol %, or about 0.5 mol % to about 5 mol % of a crystalline tungsten bronze phase containing WO nanoparticles. x The WO nanoparticles are encapsulated within the residual glass phase and, in some embodiments, are dispersed throughout it. x WO nanoparticles are disposed at or near the surface of the glass-ceramic. In some embodiments, the crystalline M x The WO nanoparticles are platelet-shaped and have an average diameter ranging from about 10 nm to 1000 nm, or from about 10 nm to about 5 μm, as determined by means known in the art (e.g., SEM and / or TEM microscopy, X-ray diffraction, light scattering, centrifugation, etc.), and / or xWO3 nanorods have a high aspect ratio and an average length ranging from 10 nm to 1000 nm, determined by means known in the art, and an average width ranging from about 2 to about 75 nm, determined by means known in the art. In some embodiments, a tungsten bronze glass ceramic exhibiting high visible transmittance and strong UV and NIR absorption has a high aspect ratio (length / width) M with an average length ranging from about 10 nm to about 200 nm and an average width ranging from about 2 nm to 30 nm. x contains WO3 rods. This crystalline tungsten bronze phase has the formula M x WO3, where M is at least one of H, Li, Na, K, Rb, Cs, Ca, Sr, Ba, Zn, Cu, Ag, Sn, Cd, In, Tl, Pb, Bi, Th, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and U, and 0 < x < 1. These glass ceramics have a low coefficient of thermal expansion (CTE), strong attenuation or blocking of ultraviolet (UV) radiation at wavelengths less than about 250 nm and near-infrared (NIR) radiation at wavelengths ranging from about 700 nm to about 2500 nm.

[0025] In some embodiments, the glass-ceramics described herein are optically transparent in the visible (i.e., wavelengths from about 400 nm to about 700 nm) range of the spectrum. That is, the glass-ceramics have a transmittance (expressed herein as "% / mm") of greater than about 1% over a 1 mm optical path length over at least one 50 nm-wide wavelength band of light ranging from about 400 nm to about 700 nm. In some embodiments, the glass-ceramics have a transmittance of at least about 10% / mm, in some embodiments greater than about 30% / mm, and in other embodiments greater than about 50% / mm (e.g., ≥ 75% / mm, ≥ 80% / mm, ≥ 90% / mm) over at least one 50 nm-wide wavelength band of light in the visible region of the spectrum. Moreover, these glass-ceramics absorb light in the ultraviolet (UV) region (wavelengths less than about 370 nm) and near-infrared (NIR) region (greater than about 700 nm to about 1700 nm) of the spectrum without the use of coatings or films. The coating or film is mechanically fragile and sensitive to ultraviolet light and moisture. In some embodiments, the glass-ceramic has a transmittance of less than 10% / mm, or even less than 5% / mm, and in other embodiments, less than 2% / mm or even less than 1% / mm, for light having a wavelength of about 370 nm or less (e.g., at a wavelength of 370 nm). In some embodiments, for light having a wavelength of about 370 nm or less, the glass-ceramic has an absorptance or absorbs at this wavelength (e.g., at a wavelength of 370 nm) of at least 90% / mm, in other embodiments at least 95% / mm, in other embodiments at least 98% / mm, or even at least 99% / mm. In some embodiments, the glass-ceramic has a transmittance of less than 10% / mm, and in other embodiments, less than 5% / mm, for light in the NIR region of the spectrum (i.e., from about 700 nm to about 2500 nm) over at least one 50 nm-wide wavelength band of light.In some embodiments, the glass-ceramic absorbs at least 90% / mm, and in other embodiments at least 95% / mm, of light in the NIR region of the spectrum (i.e., from about 700 nm to about 2500 nm) over at least one 50 nm wide wavelength band of light.

[0026] In some embodiments, the glass-ceramics described herein can withstand temperatures of at least about 300°C, or in some embodiments, at least about 200°C, without deteriorating their optical or mechanical properties. In some embodiments, the transmittance of the glass-ceramics between about 500 nm and about 2500 nm changes by less than 10% / mm when the glass-ceramics are heated at temperatures ranging from about 200°C to about 300°C for a period of at least one hour. These glass-ceramics, in some embodiments, are non-reactive and otherwise impermeable to oxygen, hydrogen, and moisture. The impermeability of the glass-ceramics has been demonstrated by exposing selected samples (e.g., Samples 13, 14, 15, and 16 in Table 1) to 312 nm and 365 nm light for periods of up to seven days. After such exposure, no change in the optical absorption of these samples is observed, indicating that oxygen, moisture, and / or hydrogen are absorbed by the M x It does not react with the WO3 crystalline phase, x This indicates that the WO3 crystal phase was not changed.

[0027] In some embodiments, the glass-ceramics described herein have a melting point of about 75×10 at temperatures ranging from about 0° C. to about 300° C. -7 / °C. In some embodiments, the glass-ceramic has a coefficient of thermal expansion (CTE) of about 33.5×10 / °C at temperatures ranging from about 0°C to about 300°C. -7 / ℃ to approximately 66.3 × 10 -7 / °C (e.g., Samples 2, 11, 12, 13, and 54 in Table 1).

[0028] In some embodiments, the glass-ceramics described herein are faint--i.e., crystalline M x WO3 can be "quenched" by heat treating the glass / glass-ceramic above its respective softening point for a short period of time. Such heat treatment can be performed using energy sources known in the art, including, but not limited to, resistance furnaces, lasers, microwaves, etc. For example, composition 37 (Table 1) can be faded by holding the material at a temperature between about 685°C and about 740°C for about 5 minutes. The M x The WO3 bronze phase may be reformed or recrystallized at the surface of the material upon exposure to a UV pulsed laser; that is, the tungsten bronze phase reforms in the areas exposed to the laser.

[0029] The glass-ceramics described herein may be used in low-emissivity glazings in architectural, automotive, medical, aerospace, or other applications, including heat shields, medical eyewear, optical filters, etc. In some embodiments, the glass-ceramics form part of a consumer electronics device, such as a mobile phone, smartphone, laptop computer, or tablet. Such consumer electronics devices typically include a housing having a front, back, and sides, and include electrical components at least partially within the housing. The electrical components include at least a power supply, a controller, memory, and a display. In some embodiments, the glass-ceramics described herein comprise at least a portion of a protective element, such as, but not limited to, the housing and / or the display.

[0030] In some embodiments, the glass phase is a borosilicate glass, the glass-ceramic comprises SiO, AlO, BO, WO, and at least one alkali metal oxide RO, where RO is at least one of NaO, KO, CsO, and / or RbO, and the crystalline tungsten bronze phase is a tungsten bronze solid solution containing, comprising, or consisting essentially of MWO, where M is at least one of NaO, KO, CsO, and RbO. In some embodiments, the crystalline alkali tungsten bronze phase is an alkali tungsten bronze solid solution M1. x M2 y WO3, where M1 = Li, Na, K, Cs, Rb and M2 = Li, Na, K, Cs, Rb, where M1 ≠ M2 and 0 < (x + y) < 1.

[0031] In some embodiments, the glass ceramic comprises from about 56 mol% to about 78 mol% of SiO2 (56 mol% ≤ SiO2 ≤ 78 mol%) or from about 60 mol% to about 78 mol% of SiO2 (60 mol% ≤ SiO2 ≤ 78 mol%); from about 8 mol% to about 27 mol% of B2O3 (8 mol% ≤ B2O3 ≤ 27 mol%); from about 0.5 mol% to about 14 mol% of Al2O3 (0.5 mol% ≤ Al2O3 ≤ 14 mol%); more than 0 mol% to about 10 mol% of at least one of Na2O, K2O, Cs2O, and Rb2O (0 mol% ≤ Na2O + K2O + Cs2O + Rb2O ≤ 9 mol%); from about 1 mol% to about 10 mol% of WO3 (1 mol% ≤ WO3 ≤ 10 mol%) or in some embodiments, from about 1 mol% to about 5 mol% of WO3 (1 mol% ≤ WO3 ≤ 5 mol%); and from 0 mol% to about 0.5 of SnO2 (0 mol% ≤ SnO2 ≤ 0.5). In some embodiments, the glass ceramic may comprise from 0 mol% to about 9 mol% of Li2O; in some embodiments, from 0 mol% to about 9 mol% of Na2O (0 mol% < Na2O ≤ 9 mol%); in some embodiments, from 0 mol% to about 9 mol% of K2O (0 mol% < K2O ≤ 9 mol%) or from 0 mol% to about 3 mol% of K2O (0 mol% < K2O ≤ 3 mol%); in some embodiments, from 0 mol% to about 10 mol% of Cs2O (0 mol% < Cs2O ≤ 10 mol%) or more than 0 mol% to about 7 mol% of Cs2O (0 mol% < Cs2O ≤ 7 mol%); and / or in some embodiments, from 0 mol% to about 9 mol% of Rb2O (0 mol% < Rb2O ≤ 9 mol%). In some embodiments, the glass ceramic comprises from about 9.8 mol% to about 11.4 mol% of B2O3 (9.8 mol% ≤ B2O3 ≤ 11.4 mol%).

[0032] In certain embodiments, the glass-ceramics described herein comprise from about 80 mole % to about 97 mole % of SiO2 (80 mole % ≤ SiO2 ≤ 97 mole %); from 0 mole % to about 5 mole % of Al2O3 (0 mole % ≤ Al2O3 ≤ 5 mole %); from 0 mole % to about 2 mole % of R2O (0 mole % ≤ R2O ≤ 2 mole %), where R2O = Li2O, Na2O, K2O, and / or Cs2O, or from greater than 0 mole % to about 2 mole % of Cs2O (0 mole % < Cs2O ≤ 2 mole %), or from greater than 0 mole % to about 0.5 mole % of Cs2O (0 mole % < Cs2O ≤ 0.5 mole %); and from about 0.2 mole % to about 2 mole % of WO3 (0.2 mole % ≤ WO3 ≤ 2 mole %). In a particular embodiment, the glass-ceramic comprises from about 87 mole % to about 93 mole % of SiO2 (87 mole % ≤ SiO2 ≤ 93 mole %); from 0 mole % to about 0.5 mole % of Al2O3 (0 mole % ≤ Al2O3 ≤ 0.5 mole %); from 3 mole % to about 6 mole % of B2O3 (3 mole % ≤ B2O3 ≤ 6 mole %); from 0.75 mole % to about 1.25 mole % of WO3 (0.75 mole % ≤ WO3 ≤ 1.25 mole %); and from 0.2 mole % to about 2 mole % of R2O, where R = Li, Na, K, and / or Cs (0.2 mole % ≤ R2O ≤ 2 mole %).

[0033] In some embodiments, the glass-ceramic may further comprise up to about 0.5 mole % of MgO (0 mole % ≤ MgO ≤ 0.5 mole %); up to about 2 mole % of P2O5 (0 mole % ≤ P2O5 ≤ 2 mole %); and up to about 1 mole % of ZnO (0 mole % ≤ ZnO ≤ 1 mole %). The formation rate of M during cooling or heat treatment x The formation rate of WO3 can be increased by adding at least one of MgO (e.g., Samples 55, 56, and 57 in Table 1), P2O5 (e.g., Sample 58 in Table 1), and ZnO (e.g., Sample 59 in Table 1).

[0034] Non-limiting compositions of glass-ceramics that are transparent in the visible range and absorb UV and NIR are listed in Table 1. Compositions that do not absorb either UV or NIR radiation are listed in Table 2.

[0035] Table 1-1

[0036] Table 1-2

[0037] Table 1-3

[0038] Table 1-4

[0039] Table 1-5

[0040] Table 1-6

[0041] Table 2-1

[0042] Table 2-2

[0043] Table 2-3

[0044] In some embodiments, −10 mol%≦R2O(mol%)−Al2O3(mol%)≦0.1 mol%. Peraluminous melts can be classified into three subcategories based on how composition and heat treatment affect the optical properties of the glass-ceramics. As used herein, the term “peraluminous melts” refers to melts in which the molar ratio or content of alumina is greater than that of R2O, where R2O is at least one of Li2O, Na2O, K2O, and Cs2O; i.e., Al2O3(mol%)>R2O(mol%). The first subcategory is one in which the peraluminous melts are transparent in the visible wavelength range and NIR region when quenched from the molten state and after slow cooling (e.g., Samples 12, 15-17, 20, 23, 25, 33, 35-42, 44, 46, 47, and 48 in Table 1). These materials are NIR-absorbing nanocrystalline M x Subsequent heat treatment at or slightly above the annealing temperature but below the softening point is required to generate the WO3 phase. The change in optical properties as a function of heat treatment is shown in Figure 1, which is a plot of absorbance versus wavelength for splat-quenched, annealed, and heat-treated samples of Composition 13. As used herein, the term "splat-quenching" refers to the process of pouring a small amount of molten glass or "lump" of it onto a room-temperature steel plate, quenching the glass, and immediately applying pressure to the lump with an iron plunger (also at room temperature) to compress the lump into a thin (3-6 mm) disk of glass. The splat-quenched sample (Figure 1A) and annealed sample (B) of Composition / Sample 13 show no absorption in the visible or NIR regions, whereas the heat-treated samples (C, D, and E) show increasing absorption in the NIR region with increasing heat treatment time and some visible light attenuation in the 600-700 nm wavelength range, resulting in a blue-tinted material.

[0045] A second class of peraluminous melts remains transparent in the visible and NIR regions when quenched, but exhibits NIR absorption after slow cooling (see samples 12, 14, 19, 21, 22, 24, and 26-32 in Table 1). As with the previously described group of peraluminous melts, the NIR absorption of splat-quenched or slow-cooled glass-ceramics can be enhanced by further heat treatment, as shown in Figure 2, which shows the spectra of splat-quenched (A), slow-cooled (B), and heat-treated (C) samples of glass-ceramic composition 11.

[0046] A third category of peraluminous melts exhibits NIR absorption even upon quenching (see samples 1 and 7 in Table 1). The NIR absorption of these materials can be further improved by subsequent heat treatment at the annealing point or at a higher temperature but below the softening point.

[0047] Nearly charge-balanced melts (i.e., R2O (mol %) - Al2O3 (mol %) = 0 ± 0.25 mol %), when quenched, can be visibly transparent and NIR-absorbing after annealing (see Samples 8-11 and 45 in Table 1), or can be NIR-absorbing after either quenching or annealing (see Samples 2-7 in Table 1). As with the melts described previously, NIR absorption can be further enhanced by subsequent heat treatment at or above the annealing point but below the softening point.

[0048] Two peraluminous (i.e., R2O (mol %) > Al2O3 (mol %)) UV and NIR absorbing melts (samples 46 and 50 in Table 1) were transparent in the visible and NIR when quenched, but were NIR absorbing after annealing. As for the melts described previously, the NIR absorption can be further enhanced by subsequent heat treatment at or above the annealing point but below the softening point.

[0049] Crystalline M xThe WO3 phase determines the optical absorption, and its rate of formation can also be tuned by adjusting at least one of the following: heat treatment and temperature; (R2O (mol%) + Al2O3 (mol%)) / WO3 (mol%) ratio; R2O (mol%) / WO3 (mol%) ratio; Al2O3 (mol%) / WO3 (mol%) ratio; and the selection of alkali to be batched. In all cases, longer heat treatment times result in more crystalline M x The WO3 phase precipitates, resulting in a material with stronger NIR absorption. However, excessive heat treatment time can lead to the crystalline M x The WO3 phase can become coarsened. In some cases, the coarsening can be accompanied by the formation of secondary or tertiary crystalline phases such as borastalite or aluminum borate. The formation of these secondary phases can result in a material that scatters visible wavelengths of light and therefore appears hazy or milky. Moreover, in most cases, M x The rate of WO3 formation increases as the heat treatment temperature increases and approaches the softening point of the glass.

[0050] In some embodiments, 1≦(R2O(mol%)+Al2O3(mol%)) / WO3(mol%)≦6. As the ratio (R2O(mol%)+Al2O3(mol%)) / WO3(mol%) increases, M x The rate of WO3 formation decreases. When (R2O (mol%) + Al2O3 (mol%)) / WO3 (mol%) ≥ 6, NIR-absorbing crystalline M x The WO3 phase will no longer precipitate from the melt.

[0051] Crystalline M xIn those glasses in which a WO3 NIR-absorbing phase precipitates, the ratio R2O(mol%) / WO3(mol%) is greater than or equal to 0 and less than or equal to 4 (0≦R2O(mol%) / WO3(mol%)≦4), and the ratio Al2O3(mol%) / WO3(mol%) is in the range of about 0.66 to about 6 (0.66≦Al2O3(mol%) / WO3(mol%)≦6). If the R2O(mol%) / WO3(mol%) ratio is greater than 4 (R2O(mol%) / WO3(mol%)>4), the glass will precipitate and separate a dense immiscible second phase, resulting in a heterogeneous melt. If the Al2O3(mol%) / WO3(mol%) ratio is greater than 6 (Al2O3(mol%) / WO3(mol%)>6), the glass will exhibit a crystalline M x When the Al2O3 (mol%) / WO3 (mol%) ratio is equal to 6 (Al2O3 (mol%) / WO3 (mol%)=6), as in Sample 34 in Table 1, the NIR-absorbing nanocrystalline M x WO3 bronze forms, but very slowly. It is preferred that the R2O (mol%) / WO3 (mol%) ratio be in the range of about 0 to about 3.5 (0≦R2O / WO3≦3.5) (e.g., Sample 26 in Table 1). It is most preferred that the R2O / WO3 be in the range of about 1.25 to about 3.5 (1.25≦R2O (mol%) / WO3 (mol%)≦3.5) (e.g., Sample 53 in Table 1). Because samples within this composition range exhibit UV and NIR absorbing M x The WO3 crystalline phase precipitates rapidly, exhibiting high visible transparency with strong NIR absorption and fading (i.e., M x The ratio Al2O3(mol%) / WO3(mol%) is in the range of about 0.66 to about 4.5 in certain embodiments (0.66≦Al2O3(mol%) / WO3(mol%)≦4.5) (e.g., Sample 40 in Table 1), and most preferably Al2O3(mol%) / WO3(mol%) is in the range of about 2 to about 3 (1≦Al2O3(mol%) / WO3(mol%)≦3) (e.g., Sample 61 in Table 1). Above this range, the NIR-absorbing nanocrystalline M x WO3 bronze slowly forms.

[0052] Different alkali metal oxides precipitate the crystalline M x WO3 phase at different rates. For melts having the same batch composition but different alkali metal oxides R2O (where R = Li, Na, K, or Cs), the M x WO3 precipitation rate is slowest when M (or R) is Cs and fastest when M (or R) is Li - i.e., Cs < K < Na < Li (e.g., Samples 14, 15, 16, and 13 in Table 1). The temperature at which the crystalline M x WO3 phase forms in the glass-ceramic also shifts depending on the alkali metal present. Figure 3 shows the differential scanning calorimetry (DSC) cooling curves measured for Samples 14, 15, 16, and 13, whose compositions are listed in Table 1. As can be seen from Figure 3 and Table A below, the cesium-containing melt crystallizes at the highest temperature, followed by the potassium-containing melt, the sodium-containing melt, and the lithium-containing melt.

[0053]

Table 3

[0054] The peak or maximum transmission wavelength in the visible range and the NIR absorption limit of the glass-ceramic can be adjusted by composition, heat treatment time and temperature, and the choice of alkali metal oxide. The spectra of glass-ceramics containing different alkali tungsten bronzes and having the same composition otherwise (Samples 14, 15, 16, and 13 in Table 1) are shown in Figure 4. The potassium and cesium analogs (Samples 16 and 13, respectively) have peak visible transmittance wavelengths (440 - 450 nm) shorter than those of the sodium and lithium analogs (Samples 15 and 14, respectively), which have peak visible transmittance wavelengths of 460 nm and 510 nm.

[0055] In some embodiments (e.g., Samples 37, 44, 46, and 50 in Table 1), the glass-ceramics described herein have a low concentration of boron—i.e., from about 9.8 mol% to about 11.4 mol% B2O3 (9.8 mol%≦B2O3≦11.4 mol%). In these samples, the NIR-absorbing crystalline M x The WO3 phase precipitates over a narrow, low temperature range, as shown in Table B. When these compositions are heated above their respective softening points, the crystalline M x They can bend, sink, or molded without growing a WO3 phase, thereby enhancing the optical performance of these glass-ceramics through the initial formation and / or shaping of the glass article and subsequent growth of the NIR-absorbing crystalline M x The crystalline M in glass-ceramics having the above composition can be controlled and fine-tuned by heat treating the material at low temperatures to precipitate a WO second phase. x The WO second phase can be "disappeared" (the glass-ceramic can be "fade") by heating the glasses above their respective softening points for a short period of time. For example, composition 44 can be faded by holding the material at a temperature between about 685°C and about 740°C for about 5 minutes.

[0056] [Table 4]

[0057] In some embodiments, these glasses and glass-ceramics can be patterned with a UV laser. x The WO3 phase can be precipitated in a quenched composition (e.g., Sample 14 in Table 1), for example, by exposing the material to a 10 watt 355 nm pulsed laser.

[0058] Table C lists physical properties measured for selected sample compositions listed in Table 1, including strain point, anneal point, softening point, coefficient of thermal expansion (CTE), density, refractive index, Poisson's ratio, shear modulus, Young's modulus, liquidus (maximum crystallization) temperature, and stress optical coefficient (SOC). In addition, X-ray powder diffraction (XRD) profiles of splat-quenched and heat-treated glass-ceramic compositions were obtained for selected samples listed in Table 1. Figures 5 and 6 are representative XRD profiles obtained for splat-quenched and heat-treated materials, respectively, both having composition 14 in Table 1. These XRD profiles demonstrate that the as-quenched material (Figure 5) is amorphous and that the crystalline M (M) was present prior to heat treatment. x The heat-treated glass material does not contain the WO3 phase and is crystalline M x It indicates that it contains a second phase of WO3.

[0059] [Table 5-1]

[0060] [Table 5-2]

[0061] [Table 5-3]

[0062] In embodiments in which the glass-ceramic comprises alumina (Al2O3) and at least one alkali metal, the glass-ceramic may be ion-exchangeable. Ion exchange is commonly used to chemically strengthen glasses. In certain instances, alkali cations in a source of such cations (e.g., a molten salt, or "ion exchange" bath) are exchanged for smaller alkali cations in the glass to form a layer under compressive stress (CS) that extends from the surface of the glass (where CS is greatest) to the depth of layer (DOL) or compression depth DOC in the glass phase. For example, potassium ions from the cation source are often exchanged for sodium ions in the glass phase.

[0063] In some embodiments, the glass-ceramic is ion-exchanged and has a compressive layer extending from at least one surface to a depth (as indicated by DOC and / or DOL) of at least about 10 μm within the glass-ceramic, the compressive layer having a compressive stress, C, at the surface of at least about 100 MPa and less than about 1500 MPa.

[0064] In a non-limiting example, compositions 51 and 54 were ion-exchanged. The samples were first heat treated at 550°C for 15 hours, then cooled at 1°C / min to 475°C and further cooled to room temperature at the furnace cooling rate (furnace rate) when power was turned off. The cerammed samples were then ion-exchanged in a molten bath of KNO for 3 hours at 390°C, resulting in surface compressive stresses of 360 MPa and 380 MPa and depths of layer of 31 micrometers and 34 micrometers for glass-ceramic compositions 51 and 54, respectively.

[0065] In one embodiment, the glass-ceramics described herein can be produced using a melt quenching process. The components in the appropriate ratios can be mixed and blended by turbulent mixing or ball milling. The batched materials can then be melted at a temperature ranging from about 1550°C to about 1650°C, held at that temperature for a time ranging from about 6 to about 12 hours, after which time they can be cast or molded, and then slowly cooled. Depending on the composition of the material, additional heat treatment at or slightly above the annealing point, but below the softening point, can be used to produce crystalline MgO. x The WO3 second phase generates and provides UV and NIR absorption. Optimal UV and NIR absorption was obtained for the compositions of Samples 12-16, 37, 46, 50-53, and 61 in Table 1. For the exemplary compositions, crystalline M x The heat treatment times and temperature ranges used to generate the WO3 second phase are listed in Table D.

[0066] [Table 6]

[0067] In another embodiment, the glass-ceramic is formed by infiltrating a nanoporous glass, such as, but not limited to, VYCOR®, a high-silica glass manufactured by Corning Incorporated. Such nanoporous glasses can have porosities of 20 to 30% and average pore diameters of 4.5 to 16.5 nm, with a narrow pore size distribution (approximately 96% of the pores in the glass are +0.6 nm from the average diameter). The average pore diameter can be increased to approximately 16.5 nm by adjusting the heat treatment schedule required to phase separate the glass and by modifying the etching conditions. A flow diagram of a method for infiltrating a glass and forming a glass-ceramic is shown in Figure 7.

[0068] In step 110 of method 100, a first solution containing tungsten, a second solution containing metal cations M, and a third solution containing boric acid are prepared or provided to deliver these components to the nanoporous glass substrate. In one embodiment, the tungsten solution is prepared by dissolving ammonium metatungstate (AMT) in deionized water to produce the desired concentration of tungsten ions. In some embodiments, organic precursors such as tungsten carbonyl, tungsten hexachloride, etc. may be used to deliver tungsten into the pores of the nanoporous glass substrate. M x A number of aqueous precursors may also be used to provide the metal M cations in the WO3 bronze, including nitrates, sulfates, carbonates, chlorides, etc.

[0069] In one non-limiting example, a first aqueous solution of 0.068 M AMT and a second aqueous solution of 0.272 M cesium nitrate are prepared or provided such that the cesium cation concentration is one-third the tungsten cation concentration.

[0070] The third solution is a supersaturated boric acid solution, which in some embodiments can be prepared by adding boric acid hydrate to deionized water and heating the mixture to boiling with stirring.

[0071] In some embodiments (not shown in FIG. 7), the nanoporous glass may be washed before forming the glass-ceramic. A sample of the glass (e.g., a 1 mm sheet) can first be slowly heated in ambient air to a temperature of about 550°C to remove moisture and organic contaminants, and then stored at about 150°C until ready for use.

[0072] The nanoporous glass is first infiltrated with a tungsten solution by immersing the glass in a first tungsten-containing solution at room temperature (about 25° C.) (step 120). In one non-limiting example, the nanoporous glass is immersed in the first solution for about 1 hour. The glass sample is then removed from the first solution, immersed in deionized water for about 1 minute, and allowed to dry in ambient air for a time ranging from about 24 to about 72 hours.

[0073] In the next step of method 100, the infiltrated nanoporous glass sample is heated in flowing oxygen to decompose the ammonium metatungstate and form WO (step 130). The glass is first heated to about 225°C at a rate of about 1°C / min, then heated from about 225°C to about 450°C at a rate of about 2.5°C / min, held at 450°C for 4 hours, and then cooled from about 450°C to room temperature at a rate ranging from about 5°C to about 7°C per minute. Step 130, in some embodiments, can include preheating the glass to about 80°C for up to about 24 hours prior to the heat treatment.

[0074] After step 130, the glass is immersed in a second solution (step 140) at room temperature (about 25° C.) to infiltrate the glass with the M cation solution. Prior to step 140, in some embodiments, the glass may be preheated to about 80° C. for up to about 24 hours before immersion. In one non-limiting example, the nanoporous glass is immersed in the second solution for about 1 hour. The glass sample can then be removed from the second solution, immersed in deionized water for about 1 minute, and allowed to dry in ambient air for a time ranging from about 24 to about 72 hours.

[0075] After step 140, the nanoporous glass sample is heated to form crystalline tungsten bronze M xThe WO phase is formed (step 150). The heating step 150 involves first heating the glass from about 5°C to about 200°C at a rate of about 1°C / min in a nitrogen atmosphere, then heating from about 200°C to about 575°C at a rate of about 3°C / min in a 3% hydrogen and 97% nitrogen atmosphere, holding at 575°C for 1 hour, and then rapidly cooling the glass to about 300°C by opening the furnace in which the heating step was performed. In some embodiments, the sample is then left in ambient air for an indefinite period of time.

[0076] After step 150, the glass sample is immersed in a third solution, a supersaturated boric acid solution (step 160). This third solution is maintained at a boil and gently stirred during step 160. In some embodiments, the glass sample is immersed in the boiling solution for about 30 minutes. After removing the sample from the third solution, in some embodiments, the sample is rinsed with deionized water and left in ambient air for about 24 hours. The glass is then heated under a nitrogen atmosphere to form and consolidate a glass ceramic (step 170). In step 170, the glass is first heated from room temperature to about 225°C at a rate of about 1°C / min, and then heated from about 225°C to about 800°C at a rate of about 5°C / min. The glass is held at 800°C for about 1 hour and then cooled from about 800°C to room temperature at a rate of about 10°C / min.

[0077] In another aspect, glasses are provided that are doped with rare earth oxides (REO) and have high absorption in the NIR region of the spectrum. In some embodiments, these glasses contribute to the high refractive index of the glass in the IR. Rare earth oxide dopants include Sm2O3, Pr2O3, and Er2O3, which may comprise up to about 12 mole percent of the glass.

[0078] In some embodiments, the REO-doped glass is an aluminosilicate glass comprising Al2O3, SiO2, and at least one of Sm2O3, Pr2O3, and Er2O3, where Sm2O3 + Pr2O3 + Er2O3 ≦12 mol%. In some embodiments, the glass further comprises at least one alkaline earth oxide and B2O3. The glass, in some embodiments, has a transmittance of less than about 30% at wavelengths between about 1400 nm and about 1600 nm. Non-limiting examples of aluminosilicate glass compositions are listed in Table E. The measured refractive indices (RI) of these glasses are also listed in Table E. Glasses A, B, and C, which contained no alkaline earth modifier, were too viscous to pour even at 1650°C. Glasses E and F, which contained large amounts (more than 12 mol%) of alkaline earth modifier and B2O3, poured easily at 1650°C. The dispersion and percent transmittance of Glass E for both the visible and NIR regions of the spectrum are plotted in Figures 8 and 9, respectively. Glass E exhibits both a high refractive index in the infrared (IR) region and high absorption at 1550 nm. The UV-VIS-IR spectra of these compositions containing 3-5 mole % Pr2O3 are plotted in Figure 10 and show the high absorption of these glasses at 1550 nm.

[0079] [Table 7]

[0080] In some embodiments, the REO-doped glass is a zinc-bismuth borate glass containing at least one of ZnO, Bi2O3, B2O3, and at least one of Sm2O3, Pr2O3, and Er2O3, and Sm2O3 + Pr2O3 + Er2O3 ≤ 12 mol%. In some embodiments, the REO-doped Zn·Bi borate glass further contains at least one of Na2O and TeO2. These glasses have a transmittance of less than about 30% at wavelengths between about 1400 nm and about 1600 nm in some embodiments. Limited examples of the composition ratios of Zn·Bi borate glass are listed in Table F. The refractive indices (RI) measured for these glasses are also listed in Table F.

[0081]

Table 8

[0082] Although typical embodiments have been described for illustrative purposes, the foregoing description should not be considered as a limitation to the scope of the present disclosure or the scope of the appended claims. Accordingly, various modifications, applications, and alternatives will occur to those skilled in the art without departing from the scope or spirit of the appended claims or the present disclosure.

[0083] Hereinafter, preferred embodiments of the present invention will be described item by item.

[0084] Embodiment 1 In the glass ceramic, a silicate glass phase, a crystalline M of about 0.1 mol% to about 10 mol% containing nanoparticles x a WO3 phase, where M is at least one of H, Li, Na, K, Rb, Cs, Ca, Sr, Ba, Zn, Cu, Ag, Sn, Cd, In, Tl, Pb, Bi, Th, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and U, and 0 < x < 1, the crystalline M x a WO3 phase, and a glass ceramic containing the same.

[0085] Embodiment 2 2. The glass-ceramic of claim 1, wherein the glass-ceramic has a transmittance of at least 1% / mm over at least one 50 nm wide wavelength band of light for light having a wavelength in the range of about 400 nm to about 700 nm.

[0086] Embodiment 3 2. The glass-ceramic of claim 1, wherein the glass-ceramic has a transmittance of less than 1% / mm for light having a wavelength of about 370 nm or less.

[0087] Embodiment 4 2. The glass-ceramic of claim 1, wherein the glass-ceramic has a transmittance of less than 5% / mm over at least one 50 nm wide wavelength band of light for light having a wavelength in the range of about 700 nm to about 2500 nm.

[0088] Embodiment 5 5. The glass-ceramic of embodiment 4, wherein the transmittance of the glass-ceramic between about 500 nm and about 2500 nm changes by less than 10% / mm when the glass-ceramic is heated at a temperature in the range of about 200° C. to about 300° C.

[0089] Embodiment 6 6. The glass-ceramic of any one of claims 1 to 5, wherein the glass-ceramic is ion-exchangeable.

[0090] Embodiment 7 7. The glass ceramic of any one of claims 1 to 6, wherein the glass ceramic is enabled for ion exchange and has a compressive layer extending from a surface of the glass ceramic to a depth of at least about 10 μm within the glass ceramic, the compressive layer having a compressive stress at the surface of at least about 100 MPa and less than about 1500 MPa.

[0091] Embodiment 8 8. The glass-ceramic of any one of claims 1 to 7, wherein the glass-ceramic is fading by heat treatment.

[0092] Embodiment 9 The glass-ceramic has a viscosity of about 75×10 at temperatures ranging from 0° C. to about 300° C. -7 9. The glass-ceramic according to any one of embodiments 1 to 8, having a thermal expansion coefficient of 0.1 / °C or less.

[0093] Embodiment 10 10. The glass-ceramic of any one of claims 1 to 9, wherein the silicate glass phase is a borosilicate glass phase.

[0094] Embodiment 11 The glass-ceramic contains from about 0.1 mol % to about 5 mol % crystalline M x 11. The glass-ceramic of any one of embodiments 1 to 10, comprising a WO phase.

[0095] Embodiment 12 2. The glass-ceramic of embodiment 1, wherein M is at least one alkali metal.

[0096] Embodiment 13 13. The glass-ceramic of embodiment 12, wherein the glass-ceramic comprises about 56 mol% to about 78 mol% SiO; about 8 mol% to about 27 mol% BO; about 0.5 mol% to about 14 mol% AlO; greater than 0 mol% to about 10 mol% of at least one of NaO, KO, CsO, and RbO; about 1 mol% to about 10 mol% WO; and 0 mol% to about 0.5 SnO.

[0097] Embodiment 14 13. The glass-ceramic of embodiment 12, wherein M is Cs and the glass-ceramic comprises from greater than 0 mol % to about 10 mol % CsO.

[0098] Embodiment 15 13. The glass-ceramic of embodiment 12, wherein −10 mol%≦R2O(mol%)−Al2O3(mol%)≦0.1 mol%, where R2O is at least one of Na2O, K2O, Cs2O, and Rb2O.

[0099] Embodiment 16 The glass ceramic according to Embodiment 12, wherein 0 < R2O (mol%) / WO3 (mol%) ≤ 2.61, and in the formula, R2O is at least one of Na2O, K2O, Cs2O, and Rb2O.

[0100] Embodiment 17 The glass ceramic according to Embodiment 12, wherein 0.66 ≤ Al2O3 (mol%) / WO3 (mol%) ≤ 6.

[0101] Embodiment 18 The glass ceramic according to Embodiment 12, wherein 1 ≤ (R2O (mol%) + Al2O3 (mol%)) / WO3 (mol%) ≤ 6, and in the formula, R2O is at least one of Na2O, K2O, Cs2O, and Rb2O.

[0102] Embodiment 19 The glass ceramic according to Embodiment 12, further comprising at least one of up to about 0.5 mol% of MgO; up to about 2 mol% of P2O5; and up to about 1 mol% of ZnO.

[0103] Embodiment 20 The glass ceramic according to Embodiment 1, comprising from about 80 mol% to about 97 mol% of SiO2; from 0 mol% to about 5 mol% of Al2O3; greater than 0 mol% to about 2 mol% of Cs2O; and from about 0.2 mol% to about 2 mol% of WO3.

[0104] Embodiment 21 The crystalline M x The WO3 phase is composed of a plurality of small plate-shaped M x WO3 nanoparticles and a plurality of M x The glass ceramic according to Embodiment 1 or 20, comprising at least one of WO3 nanorods.

[0105] Embodiment 22 The plurality of small plate-shaped M xThe glass ceramic according to Embodiment 21, wherein the WO3 nanoparticles have an average diameter in the range of about 10 nm to 5 μm.

[0106] Embodiment 23 The plurality of M x The glass ceramic according to Embodiment 21 or 22, wherein the WO3 nanorods have an average length in the range of about 10 nm to about 1000 nm and an average width ranging from about 2 nm to about 75 nm.

[0107] Embodiment 24 The plurality of M x The glass ceramic according to Embodiment 23, wherein the WO3 nanorods have an average length in the range of about 10 nm to about 200 nm and an average width ranging from about 2 nm to about 30 nm.

[0108] Embodiment 25 The glass ceramic according to any one of Embodiments 1 to 24, wherein the glass ceramic is at least part of a heat shield, an optical fiber, a building component, an automotive part, or a housing of an electronic display.

[0109] Embodiment 26 In the glass ceramic, A silicate glass phase, Crystalline M containing nanoparticles, in an amount of about 0.1 mol% to about 10 mol% x A WO3 phase, where M is at least one alkali metal and 0 < x < 1, crystalline M x A WO3 phase, And a glass ceramic containing the same.

[0110] Embodiment 27 The glass ceramic according to Embodiment 26, wherein the glass ceramic contains about 0.1 mol% to about 5 mol% of crystalline M x WO3 phase.

[0111] Embodiment 28 The glass ceramic according to Embodiment 26, wherein the silicate glass phase is a borosilicate glass phase.

[0112] Embodiment 29 The glass ceramic of embodiment 26, wherein the glass ceramic comprises from about 56 mol% to about 78 mol% SiO2; from about 9 mol% to about 27 mol% B2O3; from about 0.5 mol% to about 14 mol% Al2O3; more than 0 mol% to about 9 mol% of at least one of Na2O, K2O, Cs2O, and Rb2O; from about 1 mol% to about 10 mol% WO3; and from 0 mol% to about 0.5 SnO2. <0​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​27. The glass-ceramic of claim 26, wherein the glass-ceramic has a transmittance of at least 1% / mm over at least one 50 nm wide wavelength band of light for light having a wavelength in the range of about 400 nm to about 700 nm.

[0119] Embodiment 36 27. The glass-ceramic of claim 26, wherein the glass-ceramic has a transmittance of less than 1% / mm for light having a wavelength of about 370 nm or less.

[0120] Embodiment 37 37. The glass ceramic of any one of claims 26 to 36, wherein the glass ceramic has a transmittance of less than 5% / mm over at least one 50 nm wide wavelength band of light for light having a wavelength in the range of about 700 nm to about 2500 nm.

[0121] Embodiment 38 38. The glass-ceramic of embodiment 37, wherein the transmittance of the glass-ceramic between about 500 nm and about 2500 nm changes by less than 10% / mm when the glass-ceramic is heated at a temperature in the range of about 200°C to about 300°C.

[0122] Embodiment 39 27. The glass-ceramic of embodiment 26, wherein the glass-ceramic is ion-exchangeable.

[0123] Embodiment 40 40. The glass ceramic of embodiment 39, wherein the glass ceramic is ion-exchangeable and has a compressive layer extending from a surface of the glass ceramic to a depth of at least about 10 μm within the glass ceramic, the compressive layer having a compressive stress at the surface of at least about 100 MPa and less than about 1500 MPa.

[0124] Embodiment 41 27. The glass-ceramic of embodiment 26, wherein the glass-ceramic is fading by heat treatment.

[0125] Embodiment 42 27. The glass-ceramic of embodiment 26, wherein the glass-ceramic is impermeable to moisture and oxygen.

[0126] Embodiment 43 27. The glass-ceramic of embodiment 26, wherein M comprises Cs, and the glass-ceramic comprises about 80 mol% to about 97 mol% SiO; 0 mol% to about 5 mol% AlO; greater than 0 mol% to about 2 mol% CsO; and about 0.2 mol% to about 2 mol% WO.

[0127] EMBODIMENT 44 The crystalline M x The WO3 phase is composed of multiple small platelet-shaped M x WO3 nanoparticles and multiple M x 27. The glass-ceramic of embodiment 26, comprising at least one WO nanorod.

[0128] Embodiment 45 The plurality of small platelet shapes M x 45. The glass-ceramic of embodiment 44, wherein the WO nanoparticles have an average diameter ranging from about 10 nm to 5 μm.

[0129] Embodiment 46 The plurality of M x 45. The glass-ceramic of embodiment 44, wherein the WO nanorods have an average length ranging from about 10 nm to about 1000 nm and an average width ranging from about 2 nm to about 75 nm.

[0130] Embodiment 47 The plurality of M x 47. The glass-ceramic of embodiment 44 or 46, wherein the WO nanorods have an average length ranging from about 10 nm to about 200 nm and an average width ranging from about 2 nm to about 30 nm.

[0131] Embodiment 48 48. The glass-ceramic of any one of embodiments 26 to 47, wherein the glass-ceramic is at least part of a heat shield, an optical fiber, an architectural component, an automotive part, or a protective element for an electronic display.

[0132] Embodiment 49 An aluminosilicate glass comprising Al2O3 and SiO2, and at least one of Sm2O3, Pr2O3, and Er2O3, wherein Sm2O3 + Pr2O3 + Er2O3 ≦ 12 mol %.

[0133] Embodiment 50 50. The aluminosilicate glass of embodiment 49, further comprising at least one alkaline earth oxide and B2O3.

[0134] Embodiment 51 51. The aluminosilicate glass of claim 49 or 50, wherein the aluminosilicate glass has a transmission of less than about 30% at wavelengths between about 1400 nm and about 1600 nm.

[0135] Embodiment 52 A zinc-bismuth-borate glass comprising ZnO, Bi2O3, B2O3, and at least one of Sm2O3, Pr2O3, and Er2O3, wherein Sm2O3 + Pr2O3 + Er2O3 ≦ 12 mol %.

[0136] Embodiment 53 53. The zinc bismuth borate glass of embodiment 52, further comprising at least one of Na2O and TeO2.

[0137] EMBODIMENT 54 54. The zinc bismuth borate glass of claim 52 or 53, wherein the zinc bismuth borate glass has a transmittance of less than about 30% at wavelengths between about 1400 nm and about 1600 nm.

Claims

1. 1. A method of forming a glass-ceramic article, the method comprising: M ｘ WO ３ wherein 0<x<1 and M comprises H, Li, Na, K, Rb, Cs, Ca, Sr, Ba, Zn, Cu, Ag, Sn, Cd, In, Tl, Pb, Bi, Th, La, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, and / or U. and At least prior to the step of heat treating the glass, the glass is ２ , B ２ O ３ , Al ２ O ３ , and W.O. ３ Including, A method for forming a glass-ceramic article.

2. 10. The method of claim 1, wherein the glass-ceramic article has a transmission of greater than 1% over at least one 50 nm wide wavelength band of light in the range of 400 nm to 700 nm over a 1 mm optical path length.

3. The method of claim 1 , wherein the glass-ceramic article has a transmission of less than 5% at a wavelength of 370 nm over a 1 mm path length.

4. 1. A method of forming a glass-ceramic article, the method comprising: By heat treating at a temperature higher than the softening point, M ｘ WO ３ fading a glass-ceramic comprising crystals of

5. The method of claim 4 , wherein the heat treatment comprises using a laser.

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