Patent Application
20200039877
The disclosure relates generally to displays having reduced electrostatic surface charge and methods for reducing surface charge in such displays, and more particularly to displays including a cover glass sheet having at least one depleted or enriched surface layer to reduce mura and/or unintended liquid crystal modulation caused by the build-up of electrostatic charge.
Displays with a thin film transistor (TFT) liquid crystal display (LCD) are commonly incorporated into touchscreen devices such as smartphones. TFT LCDs typically have liquid crystals, TFTs, a VCOM layer, and a color filter arranged between a color filter glass and a TFT array glass. A polarizer and a cover glass are also typically arranged above the color filter glass. One or more touch sensors may also be included in a display to provide combined touch and display functionality, referred to herein as a “touch-display” assembly, such as an LCD touch screen.
LCD touch screens can be arranged in various configurations, including “on cell,” “in-cell,” or “in-cell hybrid” configuration. In an on-cell configuration the touch sensor is disposed on an outer surface of the color filter glass, e.g., a surface facing the user. In an in-cell configuration the touch sensor is disposed within the cell, e.g., between the TFT array glass and the color filter glass. An in-cell hybrid configuration can comprise receive (RX) sensor layers arranged in a y direction and transmit (TX) sensor layers arranged in the x direction. The RX sensor layer is disposed on an outer surface of the color filter glass and the TX sensor layer is combined with the VCOM layer and is disposed between the color filter glass and the TFT array glass. Thus an exemplary in-cell hybrid display would at least include: a TFT array glass; TFTs disposed on the TFT array glass; the combined VCOM and TX sensor layer disposed on the TFTs; the liquid crystal layer disposed on the combined VCOM and TX sensor layer; the color filter disposed on the liquid crystal layer; the color glass filter disposed on the color filter; the RX sensors layer disposed on the color filter glass; a polarizer disposed on the RX sensors layer, and a cover glass disposed on the polarizer.
When static electricity is created on the cover glass bonded to an in-cell hybrid display, for example by moving a finger across the cover glass, an electrostatic charge builds up and creates an electric field between the RX sensor layer and the TX sensor layer. The electric field can lead to unintentional modulation of the liquid crystal layer which, in turn, leads to light leakage, also referred to herein as mura. As such, there is a need to solve the problem of mura induced by electrostatic charge building up on the cover glass.
The disclosure relates, in various embodiments, to methods for reducing mura in a touch-display device, the methods comprising treating a cover glass sheet to produce a depleted surface layer on at least one of a first major surface or a second major surface of the cover glass sheet and positioning the cover glass sheet proximate a liquid crystal layer in a touch-display device, wherein a surface concentration of at least one alkali metal ion in the depleted surface layer is less than a bulk concentration of the at least one alkali metal ion in the cover glass sheet, and wherein a depth of the depleted surface layer ranges from about 5 nm to about 100 nm. The disclosure also relates, in additional embodiments, to methods for reducing mura in a touch-display device, the methods comprising treating a cover glass sheet to produce an enriched surface layer on at least one of a first major surface or a second major surface of the cover glass sheet and positioning the cover glass sheet proximate a liquid crystal layer in a touch-display device, wherein a silica concentration of the enriched surface layer is greater than a bulk silica concentration of the cover glass sheet, and wherein a depth of the enriched surface layer ranges from about 5 nm to about 100 nm.
According to various embodiments, the cover glass sheet can comprise an alkali-containing glass chosen from borosilicate, aluminosilicate, and soda-lime glasses. In certain embodiments, treating the cover glass sheet can comprise at least one ion exchange step, at least one leaching or etching step, or a combination thereof. The ion exchange step can comprise a temperature ranging from about 20° C. to about 120° C. and/or a treatment period ranging from about 30 seconds to about 10 minutes. According to some embodiments, the ion exchange step comprises contacting at least one of the first and second major surfaces of the cover glass sheet with a salt bath comprising at least one cation chosen from H3O+, Na+, K+, Cs+, Ag+, and Au+.
In some embodiments, treating the cover glass sheet to create a depleted or enriched surface layer can comprise a leaching or etching step. The leaching or etching step can comprise contacting at least one of the first and second major surfaces of the cover glass sheet with a leachant or etchant comprising at least one compound chosen from fluoride compounds, mineral acids, organic acids, and combinations thereof. According to non-limiting embodiments, the etchant can comprise a combination of (a) at least one fluoride compound and (b) at least one of a mineral acid and organic acid. The leaching or etching compound(s) can, in various embodiments, be chosen from HF, NH4F, F2H5N, NaF, KF, HCI, HNO3, H2SO4, H3PO4, and CH3COOH. The leaching or etching step can comprise a temperature ranging from about 20° C. to about 90° C. and/or a treatment time ranging from about 10 seconds to about 10 minutes.
Also disclosed herein are devices comprising a liquid crystal layer and a cover glass sheet positioned proximate the liquid crystal layer and comprising first and second major surfaces, wherein at least one of the first and second major surfaces comprises a depleted surface layer, wherein a surface concentration of at least one alkali metal ion in the depleted surface layer is less than a bulk concentration of the at least one alkali metal ion in the cover glass sheet, and wherein a depth of the depleted surface layer ranges from about 5 nm to about 100 nm. The disclosure further relates to devices comprising a liquid crystal layer and a cover glass sheet positioned proximate the liquid crystal layer and comprising first and second major surfaces, wherein at least one of a first major surface and a second major surface of the cover glass sheet comprises an enriched surface layer having a silica concentration greater than a bulk silica concentration of the cover glass sheet, and wherein a depth of the enriched surface layer ranges from about 5 nm to about 100 nm. Display, electronic, and lighting devices comprising such devices are also disclosed herein.
According to various embodiments, the cover glass sheet can comprise an alkali-containing glass chosen from borosilicate, aluminosilicate, and soda-lime glasses. In non-limiting embodiments, the alkali metal ion is lithium. According to additional embodiments, the surface concentration of the at least one alkali metal ion in the depleted surface layer ranges from 0 mol % to about 5 mol %. In further embodiments, the silica concentration of the enriched surface layer is at least about 1 mol % greater than the bulk silica concentration of the cover glass sheet. According to yet further embodiments, both the first and second major surfaces of the cover glass sheet can comprise a depleted or enriched surface layer. In various embodiments, the device is a liquid crystal touch-display further comprising at least one of a polarizer, a receive (RX) sensor layer, a transmit (TX) sensor layer, a thin film transistor (TFT) array, a color filter glass, a color filter, and an anti-finger print layer.
Additional features and advantages of the disclosure will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments as described herein, including the detailed description which follows, the claims, as well as the appended drawings.
It is to be understood that both the foregoing general description and the following detailed description are merely exemplary, and are intended to provide an overview or framework for understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding of the disclosure, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the disclosure and together with the description serve to explain the principles and operations of the various embodiments.
The following detailed description can be further understood when read in conjunction with the following drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.
Various embodiments of the disclosure will now be discussed with reference to
Methods
Disclosed herein are methods for reducing mura in a touch-display device, the methods comprising treating a cover glass sheet to produce a depleted surface layer on at least one of a first major surface or a second major surface of the cover glass sheet and positioning the cover glass sheet proximate a liquid crystal layer in a touch-display device, wherein a surface concentration of at least one alkali metal ion in the depleted surface layer is less than a bulk concentration of the at least one alkali metal ion in the cover glass sheet, and wherein a depth of the depleted surface layer ranges from about 5 nm to about 100 nm.
Also disclosed herein are methods for reducing mura in a touch-display device, the methods comprising treating a cover glass sheet to produce an enriched surface layer on at least one of a first major surface or a second major surface of the cover glass sheet and positioning the cover glass sheet proximate a liquid crystal layer in a touch-display device, wherein a silica concentration of the enriched surface layer is greater than a bulk silica concentration of the cover glass sheet, and wherein a depth of the enriched surface layer ranges from about 5 nm to about 100 nm.
The terms “first” and “second” major surfaces may be used herein interchangeably to refer to opposing major surfaces of a component. In some embodiments, a “first” major surface may denote a front surface facing an intended user, e.g., emitting light toward or displaying an image to a user. Similarly, a “second” major surface may denote a rear surface facing away from the user, e.g., towards a rear panel of a device, if present.
In various embodiments, additional components and/or layers may be present in the display device 100. Referring again to the non-limiting embodiment depicted in
In the in-cell hybrid configuration illustrated in
The TFT assembly 145 can comprise various components and/or layers, such as a layer of individual pixel electrodes and a common voltage (VCOM) electrode layer shared by all pixels. In the illustrated in-cell hybrid configuration, the transmit (TX) sensor layer 155 may also serve as the common voltage (VCOM) electrode layer and thus, may be interchangeably referred to herein as the TX/VCOM layer. Together with pixel electrodes 150, the TX/VCOM layer 155 can generate an electric field upon application of voltage across the electrodes. This electric field can determine the orientation direction of liquid crystal molecules in the liquid crystal layer 140. A TFT glass 160 may be used as a support for the various components of the TFT array.
The term “positioned between” and variations thereof is intended to denote that a component or layer is located between the listed components, but not necessarily in direct physical contact with those components. For instance, the polarizer 115 is positioned between the RX sensor layer 125 and cover glass 105 as illustrated in
Similarly, the term “positioned proximate” and variations thereof is intended to denote that a component or layer is located near a listed component, but not necessarily in direct physical contact with that component. Other layers or components may be positioned between two components or layers that are positioned proximate each other. For instance, the cover glass 105 is positioned proximate the LC layer 140 as illustrated in
Referring now to
An electric field generated by electrostatic surface charge, such as that illustrated in
To avoid the temporary period of liquid crystal misalignment depicted in
Certain embodiments of the disclosure will be discussed with reference to
As shown in
By way of non-limiting example, as shown in
The incorporation of the larger ions into the cover glass sheet and the removal of the smaller ions can form a depleted surface layer X having a lower concentration of smaller alkali metal ions m+ as compared to the bulk concentration of smaller alkali metal ions m+ in the bulk B of the cover glass sheet. Although not illustrated, the depleted surface layer may also have a lower concentration of larger alkali metal ions M+ as compared to the bulk concentration of larger alkali metal ions M+ in the bulk of the cover glass sheet, depending on the ion exchange bath composition. In certain embodiments, the depleted surface layer may comprise 0 mol % (or less than about 0.01 mol %, less than about 0.1 mol %, less than about 0.5 mol %, or less than about 1 mol %) of the smaller alkali metal ion m+ and the bulk B of the cover glass may comprise greater than 0 mol % (or greater than about 0.01 mol %, less than about 0.1 mol %, less than about 0.5 mol %, or less than about 1 mol %) of the smaller alkali metal ion m+. In other embodiments, the depleted surface layer may comprise 0 mol % (or less than about 0.01 mol %, less than about 0.1 mol %, less than about 0.5 mol %, or less than about 1 mol %) of the larger alkali metal ion M+ and the bulk B of the cover glass may comprise greater than 0 mol % (or greater than about 0.01 mol %, less than about 0.1 mol %, less than about 0.5 mol %, or less than about 1 mol %) of the larger alkali metal ion M+. By decreasing the concentration and/or mobility of alkali metal ions m+ and/or M+ in the depleted surface layer X of the first and/or second major surface 105A, 105C, the charge generation of the treated surface(s) may be reduced such that electrostatic charge cannot easily be generated on the treated surface.
Ion exchange may be carried out, for example, by contacting at least one major surface of the cover glass with a salt bath for a predetermined period of time. Exemplary salts that can be used in the salt bath include, but are not limited to, LiNO3, NaNO3, KNO3, RbNO3, CsNO3, AgNO3, AuNO3, and combinations thereof. Exemplary solvents that can be used in the salt bath include, for instance, water; aliphatic alcohols, such as methanol, ethanol, and isopropanol; glycols, such as ethylene glycol and propylene glycol; and combinations thereof. A concentration of the salt(s) in the ion exchange bath can range, in some embodiments, from about 0.01M to about 3M, such as from about 0.05M to about 2M, from about 0.1M to about 1.5M, or from about 0.5 to about 1M, including all ranges and subranges therebetween.
The temperature and/or treatment period for the ion exchange step can vary but may, in certain embodiments, be mild as compared to traditional ion exchange strengthening processes. By way of a non-limiting example, the temperature of the salt bath may range from about 20° C. to about 120° C., such as from about 30° C. to about 100° C., from about 40° C. to about 90° C., from about 50° C. to about 80° C., or from about 60° C. to about 70° C., including all ranges and subranges therebetween. Similarly, the treatment period may be shorter than traditional ion exchange strengthening processes and may, for example, range from about 30 seconds to about 10 minutes, such as from about 45 seconds to about 9 minutes, from about 1 minute to about 8 minutes, from about 2 minutes to about 7 minutes, from about 3 minutes to about 6 minutes, or from about 4 minutes to about 5 minutes, including all ranges and subranges therebetween.
According to various embodiments, a surface concentration of the at least one depleted alkali metal ion in the depleted surface layer X can range from 0 mol % to about 5 mol %, such as from about 0.01 mol % to about 4 mol %, from about 0.05 mol % to about 3 mol %, from about 0.1 mol % to about 2 mol %, or from about 0.5 mol % to about 1 mol %, including all ranges and subranges therebetween. In certain embodiments, the at least one depleted alkali metal ion can be chosen from Li+, Na+, or both. In other embodiments, the depleted alkali metal ion can be Li+.
Although not depicted in
Referring now to
By way of non-limiting example, as shown in
The etchant EX (or leachant) may, in some embodiments, be in the form of a solution further comprising one or more solvents and one or more etching or leaching compounds (e.g., fluoride compounds, mineral acids, and/or organic acids). Exemplary solvents that can be used in the etchant or leachant solution include, for instance, water; aliphatic alcohols, such as methanol, ethanol, and isopropanol; glycols, such as ethylene glycol and propylene glycol; and combinations thereof. A total concentration of the etching or leaching compound(s) in the solution can range, in some embodiments, from about 0.05M to about 3M, such as from about 0.1M to about 2.5M, from about 0.5M to about 2M, or from about 1M to about 1.5M, including all ranges and subranges therebetween. According to various embodiments, the concentration of fluoride compound(s) in the solution can range from about 0.01M to about 2M, such as from about 0.05M to about 1.5M, from about 0.1M to about 1M, from about 0.2M to about 0.9M, from about 0.3M to about 0.8M, from about 0.4M to about 0.7M, or from about 0.5M to about 0.6M, including all ranges and subranges therebetween. Similarly, the concentration of mineral acid(s) and/or organic acid(s) in the solution can range from about 0.01M to about 2M, such as from about 0.05M to about 1.5M, from about 0.1M to about 1M, from about 0.2M to about 0.9M, from about 0.3M to about 0.8M, from about 0.4M to about 0.7M, or from about 0.5M to about 0.6M, including all ranges and subranges therebetween.
The temperature and/or treatment period for the leaching or etching step can vary as appropriate to achieve a desired enrichment layer. By way of a non-limiting example, the leaching or etching step may be carried out at a temperature ranging from about 20° C. to about 90° C., such as from about 30° C. to about 80° C., from about 40° C. to about 70° C., or from about 50° C. to about 60° C., including all ranges and subranges therebetween. The treatment period may range, in some embodiments from about 10 seconds to about 10 minutes, such as from about 20 seconds to about 9 minutes, from about 30 seconds to about 8 minutes, from about 40 seconds to about 7 minutes, from about 1 minute to about 6 minutes, from about 2 minutes to about 5 minutes, or from about 3 minutes to about 4 minutes, including all ranges and subranges therebetween.
During the etching or leaching process, smaller alkali metal ions m+, larger alkali metal ions M+, alkaline earth metal ions A+, glass-forming ions B+, and/or metallic impurity ions z+ may migrate to the first or second major surface where they can react with the anions E− to form a reaction product or complex (e.g., E−m+, E−M+, E−A+, E−B+, E−z+), which may or may not be soluble in the etchant or leachant solution. The removal of ions m+, M+, A+, B+, and/or z+ from the cover glass sheet can form an enriched surface layer Y having a relatively high silica concentration as compared to the bulk concentration of silica in the bulk B of the cover glass sheet. The enriched surface layer Y may likewise be depleted of one or more cations and, thus, can also be described as a depleted surface layer in some embodiments.
In certain embodiments, the enriched surface layer Y may comprise at least about 0.1 mol % more silica than the bulk B of the cover glass, such as at least about 0.5 mol %, 1 mol % 2 mol %, 3 mol %, 4 mol %, 5 mol %, 6 mol %, 7 mol %, 8 mol %, 9 mol %, 10 mol %, or more, as compared to the bulk silica concentration in the bulk B of the glass. According to various embodiments, one or more cations e+, such as hydrogen (H+) ions, may also migrate into the enriched surface layer Y. By increasing the relative concentration of silica and/or hydrogen ions in the enriched surface layer Y of the first and/or second major surface 105A, 105C, the conductivity of the treated surface(s) may be increased such that electrostatic charge on the treated surface can be more quickly dissipated.
While
Of course, the cover glass may, in various embodiments, comprise only one depleted surface layer X, enriched surface layer Y, or depleted/enriched surface layer XY on the first or second major surface. Alternatively, the first and second major surfaces can comprise different layers, such as a depleted surface layer X on the first major surface and an enriched surface layer Y or depleted/enriched surface layer XY on the second major surface, or vice versa, without limitation. Additionally, while
Referring again to
In some embodiments, the layer(s) X, Y, and/or XY may be positioned on the first major (front) surface 105A of the cover glass 105 and may thus be contacted by a user, e.g., when the surface is rubbed, when a protective plastic film is removed, or when the surface is otherwise charged by user interaction. The layer(s) X, Y, and/or XY may also be positioned on the second major (rear) surface 105C of the cover glass 105 and may thus not be contacted by a user, but can still serve to reduce electrostatic charge generation and/or increase electrostatic charge dissipation. In some embodiments, generation of electrostatic charge may be reduced or eliminated by depleted surface layer X, enriched surface layer Y, or depleted/enriched surface layer XY, such that electrostatic charge sufficient to modulate the underlying LC layer cannot be generated. In additional embodiments, the depleted surface layer X, enriched surface layer Y, or depleted/enriched surface layer XY can facilitate electrostatic charge dissipation such that electrostatic charge is directed towards the edges of the glass sheet before it can accumulate and interfere with the underlying LC layer.
After treating the first and/or second major surface of the cover glass to produce the desired layer, e.g., by ion exchange and/or leaching/etching steps, the treated cover glass may be rinsed and/or dried to remove salts, etchants, reaction products, and/or solvents. For instance, the treated cover glass may be rinsed one or more times with water, such as deionized water. After rinsing, the treated cover glass can be dried at room temperature or elevated temperatures up to about 200° C. for a time period ranging from about 10 seconds to about 6 hours, such as from about 30 seconds to about 5 hours, from about 1 minute to about 4 hours, from about 5 minutes to about 3 hours, from about 10 minutes to about 2 hours, from about 20 minutes to about 1 hour, or from about 30 minutes to 40 minutes, including all ranges and subranges therebetween.
Devices
Also disclosed herein are devices comprising a liquid crystal layer and a cover glass sheet positioned proximate the liquid crystal layer and comprising first and second major surfaces, wherein at least one of the first and second major surfaces comprises a depleted surface layer, wherein a surface concentration of at least one alkali metal ion in the depleted surface layer is less than a bulk concentration of the at least one alkali metal ion in the cover glass sheet, and wherein a depth of the depleted surface layer ranges from about 5 nm to about 100 nm.
Further disclosed herein are devices comprising a liquid crystal layer and a cover glass sheet positioned proximate the liquid crystal layer and comprising first and second major surfaces, wherein at least one of a first major surface and a second major surface of the cover glass sheet comprises an enriched surface layer having a silica concentration greater than a bulk silica concentration of the cover glass sheet, and wherein a depth of the enriched surface layer ranges from about 5 nm to about 100 nm.
Referring again to
According to various embodiments, at least one of the cover glass 105, first adhesive layer 110, second adhesive layer 120, RX sensor layer 125, color filter glass 130, pixel electrodes 150, TXNCOM layer 155, and TFT glass 160 may be optically transparent. As used herein, the term “transparent” is intended to denote that the component and/or layer has a transmission of greater than about 80% in the visible region of the spectrum (˜400-700nm). For instance, an exemplary component or layer may have greater than about 85% transmittance in the visible light range, such as greater than about 90%, or greater than about 95%, including all ranges and subranges therebetween. The first and second adhesive layers 110, 120 may comprise optically clear adhesives, which may be in the form of adhesive films or adhesive liquids. Non-limiting exemplary thicknesses of the first and/or second adhesive layers 110, 120 may range from about 50 μm to about 500 μm, such as from about 100 μm to about 400 μm, or from about 200 μm to about 300 μm, including all ranges and subranges therebetween. The RX sensor layer 125, pixel electrodes 150, and/or TX/VCOM layer 155 may comprise transparent conductive oxides (TCOs), such as indium tin oxide (ITO) and other like materials. The TX/VCOM layer may also comprise a conductive mesh, e.g., comprising metals such as silver nanowires or other nanomaterials such as graphene or carbon nanotubes.
In non-limiting embodiments, the cover glass 105, color filter glass 130, and/or the TFT glass 160 may comprise optically transparent glass sheets. The glass sheets can have any shape and/or size suitable for use in a display device, such as an LCD touch screen. For example, the glass sheet can be in the shape of a rectangle, square, or any other suitable shape, including regular and irregular shapes and shapes with one or more curvilinear edges.
According to various embodiments, the cover glass 105 can have an overall thickness T (see
The cover glass 105, color filter glass 130, and/or TFT glass 160 may comprise any glass sheets known in the art for use in a display, such as an LCD touch screen, including, but not limited to, soda-lime silicate, aluminosilicate, alkali-aluminosilicate, borosilicate, alkaliborosilicate, aluminoborosilicate, alkali-aluminoborosilicate, and other suitable glasses. In some embodiments, the glass sheets can comprise an alkali-containing glass, e.g., an alkali-containing borosilicate, aluminosilicate, or soda-lime glass. The glass sheets may, in various embodiments, be chemically strengthened and/or thermally tempered. Non-limiting examples of suitable commercially available glasses include EAGLE XG®, Lotus™, Willow®, and Gorilla® glasses from Corning Incorporated, to name a few. Chemically strengthened glass, for example, may be provided in accordance with U.S. Pat. Nos. 7,666,511, 4,483,700, and 5,674,790, which are incorporated herein by reference in their entireties.
In some embodiments, the cover glass 105 may have one or more coatings on the first and/or second major surfaces 105A, 105C, which can serve various functions. For example, at least a portion of the first major surface 105A of the cover glass 105 can be coated with one or more of an anti-fingerprint, anti-smudge, anti-glare, or anti-reflective layer which can, in some embodiments, be non-conductive. In some embodiments, an anti-fingerprint coating may include a buffer layer of SiO2 and a flourosilane layer. When a user's finger moves across the cover glass with a non-conductive additional coating, static electricity can build up and cannot be quickly dissipated through the non-conductive coating. In some embodiments, the first major surface 105A can be treated to create a depleted surface layer X, enriched surface layer Y, or depleted/enriched surface layer XY that can reduce electrostatic charge generation and/or dissipate electrostatic charge. Alternatively or additionally, the layer(s) X, Y, and/or XY may be present on second major surface 105C or any portion thereof.
According to various embodiments, the depleted and/or enriched layers disclosed herein may reduce or eliminate electrostatic charge generation such that the electric field threshold for modulating the LC layer is not reached. For example, a major surface of the cover glass with a depleted and/or enriched layer can have a surface resistivity ranging from about 105 to about 1011 Ohm/sq, such as from about 106 to about 1011 Ohm/sq, from about 107 to about 1010 Ohm/sq, or from about 108 to about 109 Ohm/sq, including all ranges and subranges therebetween.
In other embodiments, the devices disclosed herein can quickly dissipate electrostatic charge on the cover glass such that the electric field threshold for modulating the LC layer is not reached. For instance, the cover glass in such display devices may have an electrostatic discharge decay time constant of less than about 1 second, such as less than about 0.5 seconds, e.g., ranging from about 0.1 seconds to about 1 second (such as 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 second). The decay time constant may be calculated as the amount of time it takes the electrostatic charge to decay by a factor of 1/e (about 36.8% of the original amount). In additional embodiments, the depleted and/or enriched layer may quickly dissipate electrostatic charge such that an electrostatic charge generated on one major surface of the cover glass is reduced to 0 V on the opposing major surface in one second or less, such as less than about 0.5 seconds, e.g., ranging from about 0.1 seconds to about 1 second (such as 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 second).
It will be appreciated that the various disclosed embodiments may involve particular features, elements or steps that are described in connection with that particular embodiment. It will also be appreciated that a particular feature, element or step, although described in relation to one particular embodiment, may be interchanged or combined with alternate embodiments in various non-illustrated combinations or permutations.
Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is no way intended that any particular order be inferred.
While various features, elements or steps of particular embodiments may be disclosed using the transitional phrase “comprising,” it is to be understood that alternative embodiments, including those that may be described using the transitional phrases “consisting” or “consisting essentially of,” are implied. Thus, for example, implied alternative embodiments to a method or device that comprises A+B+C include embodiments where a method or device consists of A+B+C and embodiments where a method or device consists essentially of A+B+C.
It will be apparent to those skilled in the art that various modifications and variations can be made to the present disclosure without departing from the spirit and scope of the disclosure. Since modifications combinations, sub-combinations and variations of the disclosed embodiments incorporating the spirit and substance of the disclosure may occur to persons skilled in the art, the disclosure should be construed to include everything within the scope of the appended claims and their equivalents.
The following Examples are intended to be non-restrictive and illustrative only, with the scope of the invention being defined by the claims.
Gorilla® Glass 3 and 5 samples were soaked in a 1M solution of NaNO3 (8.5% w/v) at 60° C. for a time period of 2 minutes or 10 minutes. After treatment, the glass samples were rinsed with deionized water at room temperature for 10 seconds. The rinsed glass samples were air dried at room temperature for 10 minutes or more and subsequently tested for charge generation using an electrostatic gauge (ESG). A stainless steel friction pad was connected to an electrometer that measures the total charge generated on the glass surface. The glass surface (charge generation area=20 mm×15 mm) was rubbed (load=0.3 lb; 5 cycles) while charging the puck equal and opposite to the glass and measuring the signal with the electrometer. The experimental set-up is illustrated in
The results of these tests for Gorilla® Glass 3 samples are presented in
The test results for Gorilla® Glass 5 samples are presented in
Gorilla® Glass 5 samples were soaked in ion exchange baths with varying concentrations of KNO3 and/or NaNO3 for varying time periods and at varying temperatures, which are listed in Table I below. The effect of the different IOX conditions on the amount of Li+ ions in the resulting depleted layer is depicted in
Gorilla® Glass 3 samples were ion exchanged in 100% KNO3 at 420° C. for 5.5 hours. Gorilla® Glass 5 samples were ion exchanged in a two-step process, with 62 wt % KNO3 and 38 wt % NaNO3 at 380° C. for 1 h 25 min in the first step, followed by 91 wt % KNO3 and 9 wt % NaNO3 at 380° C. for 33 min in the second step. The ion-exchanged Gorilla® Glass 3 and 5 samples were subsequently treated with an etchant solution comprising NaF (0.4M) and H3PO4 (1M) in water for one minute at 40° C. The treated samples were subsequently rinsed in deionized water for 1 minute and air dried at room temperature for 60 minutes. The samples were tested for charge generation using the electrostatic gauge (ESG) discussed in Example 1 with the experimental set-up illustrated in
As indicated by the plots in
Gorilla® Glass 3 and 5 samples were ion exchanged as described above in Example 3. The ion-exchanged Gorilla® Glass 3 and 5 samples were subsequently treated with a leachant solution comprising HCI (1M) in water for 2 minutes or 10 minutes at 60° C. The treated samples were subsequently rinsed in deionized water for 1 minute and air dried at room temperature for 5 minutes or more. The samples were tested for charge generation using the electrostatic gauge (ESG) discussed in Example 1 with the experimental set-up illustrated in
The results of these tests for Gorilla® Glass 3 samples are presented in
The test results for Gorilla® Glass 5 samples are presented in
Resistivity for untreated Gorilla® Glass 3 and 5 control samples, ion-exchanged Gorilla® Glass 3 and 5 samples (NaNO3, 1M, 10 minutes, 60° C.), and leached Gorilla® Glass 3 and 5 samples (HCl, 1M, 10 minutes, 60° C.) was measured using a Keysight B2987A electrometer. Using a Keysight 16008B Resistivity Cell fixture, the samples were pressed by 7 kg of force between two concentric electrodes with a perimeter of 188.5 mm and a gap of 10 mm between the inner and outer electrodes. The experimental set-up, as provided by Keysight, is illustrated in
As shown in
This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Application Ser. No. 62/550894 filed on Aug. 28, 2017, and U.S. Provisional Application Ser. No. 62/469090 filed on Mar. 9, 2017, the content of each is relied upon and incorporated herein by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US18/20155 | 2/28/2018 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62469090 | Mar 2017 | US | |
| 62550894 | Aug 2017 | US |
