Substrates with reduced electrostatic adhesion

Abstract

A substrate includes a glass sheet including opposing major surfaces and a layer including inorganic nanoparticles deposited on at least one of the major surfaces, the layer having a surface roughness of about 0.3 nm to about 3 nm and a water contact angle greater than about 5 degrees.

Description

Technical Field

[0001] The present disclosure generally relates to substrates, and more particularly to substrates having reduced electrostatic adhesion force. Background Art

[0002] Thin glass substrates are commonly used in flat panel display (FPD) devices such as liquid crystal displays (LCDs) and organic light emitting diode (OLED) displays. The substrates used in FPD devices typically have a functional A-side surface on which thin film transistors are fabricated and a non-functional back or B-side surface opposite the A-side surface. During the manufacturing process of these glass substrates, one or more of the A-side or B-side surfaces may come into contact with various material handling and processing equipment, which may cause one or more of such surfaces to become charged, for example, by triboelectric or contact electrification effects. As a result, charge is transferred to the glass surface and accumulates on the substrate. This charging can cause undesirable adhesion between the thin glass substrates, making it difficult to separate them. This may in turn require the use of an interleaf material between adjacent substrates during, for example, encapsulation and transportation operations. Therefore, there is a need to minimize such adhesion, which can, for example, reduce or eliminate the use of interleaf materials during the encapsulation and transportation of thin glass substrates. Summary of the Invention

[0003] Embodiments disclosed herein include a substrate. The substrate includes a glass sheet having a first major surface and an opposing second major surface extending in a direction generally parallel to the first major surface. The substrate further includes a layer comprising inorganic nanoparticles deposited on at least one of the first major surface and the second major surface, the layer having a surface roughness of from about 0.3 nanometers to about 3 nanometers and a water contact angle greater than about 5 degrees.

[0004] Additional features and advantages of the embodiments disclosed herein will be set forth in the detailed description below, and in part will be apparent to those skilled in the art from the description, or will be recognized in part by practice of the disclosed embodiments herein, which include the detailed description below, the claims, and the drawings.

[0005] It should be understood that the embodiments presented in the foregoing general description and the following detailed description are intended to provide an overview or framework for understanding the nature and characteristics of the claimed embodiments. The drawings are included to provide further understanding and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the present disclosure and, together with the description, are used to explain its principles and operation. Brief Description of the Drawings

[0006] Figure 1 is a schematic diagram of an exemplary fusion draw glass manufacturing apparatus and process;

[0007] Figure 2 is a perspective view of a glass sheet;

[0008] Figure 3 is a perspective view of a glass sheet immersed in a liquid dispersant;

[0009] Figure 4 is a side cross-sectional view of a glass sheet having a liquid dispersion deposition layer deposited thereon;

[0010] Figure 5 is a side cross-sectional view of a glass sheet having a deposition layer deposited thereon;

[0011] Figure 6 is a side perspective cross-sectional view of an exemplary encapsulation device containing a plurality of substrates;

[0012] Figure 7 is a graph showing the separation energy of a glass sheet or a substrate;

[0013] Figure 8 is a graph showing the contact angles of a glass sheet or a substrate with water and diiodomethane;

[0014] Figure 9 is a graph showing the Zeta potential of a glass sheet or a substrate; and

[0015] Figure 10 is a graph showing the separation energy of a glass sheet or a substrate. DETAILED DESCRIPTION

[0016] Reference will now be made in detail to the presently preferred embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals will be used throughout the drawings to refer to the same or like components. However, the present disclosure may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0017] Ranges may be expressed herein as from “about” one particular value and / or to “about” another particular value. When such a range is expressed, another embodiment includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, for example by use of the antecedent “about,” it will be understood that the particular value forms another embodiment. It should also be understood that each end point of a range is significant both in relation to the other end point and independently of the other end point.

[0018] The directional terms used herein - such as up, down, right, left, front, back, top, bottom - are made only with reference to the drawings as drawn and are not intended to imply absolute orientation.

[0019] Unless otherwise expressly stated, no method presented herein is intended to be construed as requiring its steps to be performed in a particular order or requiring any device to have a particular orientation. Accordingly, if a method claim does not actually recite the order in which its steps are to be followed, or any apparatus claim does not actually recite the order or orientation of components, or the steps are not otherwise specifically limited to a particular order in the claims or the specification, or the particular order or orientation of the components of the apparatus is not recited, no order or orientation is intended to be inferred in any respect. This applies to any possible basis for non-explicit interpretation, including: logical issues regarding step arrangement, operational flow, component order, or component orientation; simple implications from grammatical organization or punctuation, and the number or type of embodiments described in the specification.

[0020] As used herein, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" include plural referents. Thus, for example, a reference to "a" component includes aspects having two or more such components, unless the context clearly indicates otherwise.

[0021] As used herein, the term "surface roughness" refers to the roughness measured on the major surface of a substrate as determined by surface roughness measurement techniques as described herein.

[0022] As used herein, the term "Zeta potential" refers to the Zeta potential measured on the major surface of a substrate as determined by Zeta potential measurement techniques as described herein.

[0023] As used herein, the term "binding interaction energy" refers to the binding energy measured between the major surfaces of a substrate as determined by the "binding energy test conditions" as described herein.

[0024] As used herein, the term "inorganic nanoparticle" refers to a particle comprising at least one inorganic material having a maximum dimension of less than about 150 nanometers.

[0025] As used herein, the term "aspect ratio" refers to the ratio between the maximum and minimum cross-sectional dimensions of a three-dimensional particle, such as an inorganic nanoparticle. For example, a perfectly spherical particle has an aspect ratio of 1.

[0026] As Figure 1As shown, an exemplary glass manufacturing apparatus 10 is provided. In some examples, the glass manufacturing apparatus 10 may include a glass melting furnace 12, which may include a melting vessel 14. In addition to the melting vessel 14, the glass melting furnace 12 may optionally include one or more additional components, such as heating elements (e.g., burners or electrodes) that heat the raw materials and convert them into molten glass. In further examples, the glass melting furnace 12 may optionally include thermal management devices (e.g., insulation components) that reduce heat loss near the melting vessel. In still other embodiments, the glass melting furnace 12 may include electronic and / or electromechanical devices that facilitate melting the raw materials into a glass melt. Additionally, the glass melting furnace 12 may include a support structure (e.g., a support chassis, support members, etc.) or other components.

[0027] The glass melting vessel 14 generally includes a refractory material, such as a refractory ceramic material, e.g., a refractory ceramic material containing alumina or zirconia. In some examples, the glass melting vessel 14 may be constructed of refractory ceramic bricks. Specific embodiments of the glass melting vessel 14 will be described in more detail below.

[0028] In some examples, the glass melting furnace may be incorporated as a component of a glass manufacturing apparatus to manufacture glass sheets, such as a continuous length of glass ribbon. In some examples, the glass melting furnace of the present disclosure may be incorporated as a component of a glass manufacturing apparatus that includes a slot drawing apparatus, a float bath apparatus, a down-draw apparatus such as a fusion process, an up-draw apparatus, a press roller apparatus, a tube drawing apparatus, or any other glass manufacturing apparatus that would benefit from the aspects disclosed herein. By way of example, Figure 1 The glass melting furnace 12 is schematically shown as a component of a fusion down-draw glass manufacturing apparatus 10 that is used to fusion draw a glass ribbon for subsequent processing into individual glass sheets.

[0029] The glass manufacturing apparatus 10 (e.g., a fusion down-draw apparatus 10) may optionally include an upstream glass manufacturing apparatus 16 positioned upstream relative to the glass melting vessel 14. In some examples, a portion or all of the upstream glass manufacturing apparatus 16 may be incorporated as part of the glass melting furnace 12.

[0030] As shown in the illustrated example, the upstream glass manufacturing apparatus 16 may include a storage bin 18, a raw material conveying device 20, and an electric motor 22 connected to the raw material conveying device. The storage bin 18 may be configured to store a quantity of raw material 24, which may be supplied into a melting vessel 14 of the glass furnace 12, as indicated by arrow 26. The raw material 24 typically includes one or more glass-forming metal oxides and one or more modifiers. In some examples, the raw material conveying device 20 may be powered by the electric motor 22 such that the raw material conveying device 20 conveys a predetermined quantity of raw material 24 from the storage bin 18 to the melting vessel 14. In a further example, the electric motor 22 may drive the raw material conveying device 20 to introduce the raw material 24 at a controlled rate based on the level of molten glass detected downstream of the melting vessel 14. The raw material 24 within the melting vessel 14 may then be heated to form molten glass 28.

[0031] The glass manufacturing apparatus 10 may also optionally include a downstream glass manufacturing apparatus 30 positioned downstream relative to the glass furnace 12. In some examples, a portion of the downstream glass manufacturing apparatus 30 may be incorporated as part of the glass furnace 12. In some cases, the first connecting pipe 32 or other portions of the downstream glass manufacturing apparatus 30 discussed below may be incorporated as part of the glass furnace 12. Elements of the downstream glass manufacturing apparatus, including the first connecting pipe 32, may be formed of a noble metal. Suitable noble metals include platinum group metals selected from platinum, iridium, rhodium, osmium, ruthenium, and palladium, or alloys thereof. For example, the downstream components of the glass manufacturing apparatus may be formed of a platinum-rhodium alloy including about 70% to about 90% platinum and about 10% to about 30% rhodium by weight. However, other suitable metals may include molybdenum, palladium, rhenium, tantalum, titanium, tungsten, and alloys thereof.

[0032] The downstream glass manufacturing apparatus 30 may include a first conditioning (i.e., processing) vessel, such as a fining vessel 34, which is located downstream of the melting vessel 14 and is connected to the melting vessel 14 via the first connecting pipe 32 described above. In some examples, the molten glass 28 may be gravity-fed from the melting vessel 14 to the fining vessel 34 through the first connecting pipe 32. For example, gravity may cause the molten glass 28 to pass through an internal path of the first connecting pipe 32 from the melting vessel 14 to the fining vessel 34. However, it should be understood that other conditioning vessels may be located downstream of the melting vessel 14, such as between the melting vessel 14 and the fining vessel 34. In some embodiments, a conditioning vessel may be provided between the melting vessel and the fining vessel, where the molten glass from the main melting vessel is further heated to continue the melting process or cooled to a temperature below that of the molten glass in the melting vessel before entering the fining vessel.

[0033] Bubbles can be removed from the molten glass 28 within the clarification vessel 34 by a variety of techniques. For example, the feedstock 24 can include polyvalent compounds (i.e., fining agents), such as tin oxide, which undergo a chemical reduction reaction upon heating and release oxygen. Other suitable fining agents include, but are not limited to, arsenic, antimony, iron, and cerium. The clarification vessel 34 is heated to a temperature higher than the melting vessel temperature, thereby heating the molten glass and the fining agent. Oxygen bubbles generated by the chemical reduction induced by the temperature of the fining agent rise through the molten glass within the clarification vessel, where the gases within the molten glass generated in the furnace can diffuse or coalesce into the oxygen bubbles generated by the fining agent. The enlarged bubbles can then rise to the free surface of the molten glass in the clarification vessel and then be discharged from the clarification vessel. The oxygen bubbles can further cause mechanical mixing of the molten glass in the clarification vessel.

[0034] The downstream glass manufacturing apparatus 30 can also include another conditioning vessel, such as a mixing vessel 36 for mixing the molten glass. The mixing vessel 36 can be located downstream of the clarification vessel 34. The mixing vessel 36 can be used to provide a uniform glass melt composition, thereby reducing chemical or thermal non-uniformities that might otherwise be present in the clarified molten glass exiting the clarification vessel. As shown, the clarification vessel 34 can be connected to the mixing vessel 36 by a second connecting conduit 38. In some examples, the molten glass 28 can be gravity-fed from the clarification vessel 34 to the mixing vessel 36 via the second connecting conduit 38. For example, gravity can cause the molten glass 28 to reach the mixing vessel 36 from the clarification vessel 34 through the internal path of the second connecting conduit 38. It should be noted that although the mixing vessel 36 is shown downstream of the clarification vessel 34, the mixing vessel 36 can be located upstream of the clarification vessel 34. In some embodiments, the downstream glass manufacturing apparatus 30 can include multiple mixing vessels, such as a mixing vessel upstream of the clarification vessel 34 and a mixing vessel downstream of the clarification vessel 34. These multiple mixing vessels can be of the same design, or alternatively, they may be of different designs.

[0035] The downstream glass manufacturing apparatus 30 can also include another conditioning vessel, such as a delivery vessel 40 that can be located downstream of the mixing vessel 36. The delivery vessel 40 can condition the molten glass 28 to be supplied to the downstream forming device. For example, the delivery vessel 40 can act as a reservoir and / or flow controller to condition and / or provide a steady stream of molten glass 28 to the forming body 42 through an outlet conduit 44. As shown, the mixing vessel 36 can be connected to the delivery vessel 40 via a third connecting conduit 46. In some examples, the molten glass 28 can be gravity-fed from the mixing vessel 36 to the delivery vessel 40 via the third connecting conduit 46. For example, gravity can drive the molten glass 28 through the internal path of the third connecting conduit 46 from the mixing vessel 36 to the delivery vessel 40.

[0036] The downstream glass manufacturing apparatus 30 may further include a forming device 48, which includes the above-described forming body 42 and an inlet duct 50. The outlet duct 44 may be positioned to convey the molten glass 28 from the delivery vessel 40 to the inlet duct 50 of the forming device 48. For example, the outlet duct 44 may be nested within and spaced from the inner surface of the inlet duct 50, thereby providing a free surface of the molten glass between the outer surface of the outlet duct 44 and the inner surface of the inlet duct 50. The body 42 in the fusion draw glass manufacturing apparatus may include a groove 52 positioned in the upper surface of the forming body and a converging forming surface 54 that converges in the draw direction along the bottom edge 56 of the forming body. The molten glass conveyed to the groove of the forming body via the delivery vessel 40, the outlet duct 44, and the inlet duct 50 overflows the sidewalls of the groove and descends along the converging forming surface 54 as separate streams of molten glass. The separate streams of molten glass converge below and along the bottom edge 56 to produce a single glass ribbon 58, which is drawn from the bottom edge 56 in the draw or flow direction 60 by applying tension to the glass ribbon, such as by gravity, edge rollers 72, and draw rollers 82, to control the dimensions of the glass ribbon as the glass cools and the glass viscosity increases. Thus, the glass ribbon 58 undergoes a viscoelastic transition and acquires mechanical properties that impart stable dimensional characteristics to the glass ribbon 58. In some embodiments, the glass ribbon 58 may be separated into individual glass sheets 62 in the elastic region of the glass ribbon by a glass separation device 100. The robot 64 may then transfer the individual glass sheets 62 to a conveyor system using a gripping tool 65, and the individual glass sheets may subsequently be further processed.

[0037] Figure 2 A perspective view of a glass sheet 62 is shown, which has a first major surface 162, an opposing second major surface 164 (on the side of the glass sheet 62 opposite the first major surface) extending in a direction generally parallel to the first major surface 162, and edge surfaces 166 that extend between the first major surface 162 and the second major surface 164 and extend in a direction generally perpendicular to the first major surface 162 and the second major surface 164.

[0038] Figure 4 A side cross-sectional view of a glass sheet 62 having a liquid dispersion deposition layer 202 deposited thereon is shown. Specifically, the liquid dispersion deposition layer 202 is deposited on the second major surface 164 of the glass sheet 62. The liquid dispersion deposition layer 202 may be deposited on the glass sheet 62 via a dispenser 250 according to methods known to those skilled in the art, including but not limited to at least one of spin coating, flow coating, or spraying.

[0039] The liquid dispersion deposition layer 202 may be deposited on the glass sheet 62 by a dip coating method. Figure 3A perspective view of a dip coating method is shown, in which a glass sheet 62 is immersed in a liquid dispersant 200 contained in a deposition chamber 400.

[0040] In certain exemplary embodiments, the deposition layer may be dispersed in water such that the liquid-dispersed deposition layer 202 comprises an aqueous dispersion. The deposition layer may also be dispersed in other liquids, including organic solvents such as alcohols, aliphatic hydrocarbons, aromatic hydrocarbons, amines, esters, ethers, and / or ketones.

[0041] The weight percentage by weight (wt%) of solids in the liquid-dispersed deposition layer 202, while not being limited, may be, for example, in the range of about 0.1 wt% to about 10 wt%, such as in the range of about 0.5 wt% to about 5 wt%, and further such as in the range of about 1 wt% to about 3 wt%.

[0042] In certain exemplary embodiments, the liquid-dispersed deposition layer 202 may comprise a solid material that comprises inorganic nanoparticles. For example, such particles may comprise at least one of silica (SiO2) particles, alumina (Al2O3) particles, or alumina (Al2O3)-coated silica (SiO2) particles.

[0043] In certain exemplary embodiments, such particles may have an aspect ratio of less than about 4, such as an aspect ratio of about 1 to about 4, and further such as an aspect ratio of about 1 to about 2, and still further such as an aspect ratio in the range of about 1 to about 1.5, and even further such as an aspect ratio in the range of about 1 to about 1.2. For example, such particles may comprise silica (SiO2) particles having an aspect ratio of less than about 4, such as an aspect ratio ranging from about 1 to about 4, and further such as an aspect ratio ranging from about 1 to about 2, still further such as an aspect ratio ranging from about 1 to about 1.5, and even further such as an aspect ratio ranging from about 1 to about 1.2. As a further example, such particles may comprise alumina (Al2O3) particles having an aspect ratio of less than about 4, such as an aspect ratio ranging from about 1 to about 4, further such as an aspect ratio ranging from about 1 to about 2. Still further, such as an aspect ratio ranging from about 1 to about 1.5, and even further such as an aspect ratio ranging from about 1 to about 1.2.

[0044] In certain exemplary embodiments, such particles may have an aspect ratio greater than about 4, such as an aspect ratio of about 4 to about 50, and further such as an aspect ratio of about 4 to about 25, and still further such as an aspect ratio of about 4 to about 15, and yet further such as an aspect ratio ranging from about 4 to about 10. For example, such particles may include silica (SiO2) particles having an aspect ratio greater than about 4, such as an aspect ratio ranging from about 4 to about 50, further such as an aspect ratio ranging from about 4 to about 25, still further such as an aspect ratio ranging from about 4 to about 15, and yet further such as an aspect ratio ranging from about 4 to about 10. As a further example, such particles may include alumina (Al2O3) particles having an aspect ratio greater than about 4, such as an aspect ratio ranging from about 4 to about 50, and further such as an aspect ratio ranging from about 4 to about 25, still further such as an aspect ratio ranging from about 4 to about 15, yet further such as an aspect ratio ranging from about 4 to about 10.

[0045] After being deposited on the glass sheet 62, the deposited layer 202 of the liquid dispersion may undergo a drying step to evaporate the liquid, for example, by using an air knife and / or high-temperature drying known to those skilled in the art. For example, the high-temperature drying can be carried out at a temperature of at least about 100 °C, such as at least about 200 °C, such as a temperature ranging from about 100 °C to about 500 °C for at least about 10 seconds, such as from about 10 seconds to about 20 minutes. For example, the air knife drying can be carried out for at least about 30 seconds, such as a time ranging from about 30 seconds to about 30 minutes.

[0046] Figure 5 A side cross-sectional view of the glass sheet 62 having the deposited layer 204 deposited thereon is shown. Specifically, the deposited layer 204 is deposited on the second major surface 164 of the glass sheet 62 that forms the substrate 160. For example, after the aforementioned deposited layer 202 of the liquid dispersion is dried, the deposited layer 204 can be deposited on the second major surface 164 of the glass sheet 62.

[0047] The deposited layer 204 can impart a surface roughness of about 0.3 nanometers to about 3 nanometers on the second major surface 206 of the substrate 160, such as about 0.3 nanometers to about 1.5 nanometers, and further such as about 0.3 nanometers to about 0.8 nanometers. Meanwhile, the first major surface 162 of the substrate 160 can, for example, have a surface roughness of less than about 0.5 nanometers, such as less than about 0.25 nanometers, including a surface roughness ranging from about 0.05 nanometers to about 0.5 nanometers, such as about 0.1 nanometers to about 0.25 nanometers.

[0048] While Figure 5A substrate 160 is shown having a deposition layer 204 on a second major surface 164 of a glass sheet 62. Embodiments disclosed herein include those embodiments in which the deposition layer 204 is deposited on a first major surface 162 and a second major surface 164 of the glass sheet 62. In these embodiments, the two surfaces of the substrate 160 may have a surface roughness of from about 0.3 nanometers to about 3 nanometers, such as from about 0.3 nanometers to about 1.5 nanometers, and further such as from about 0.3 nanometers to about 0.8 nanometers.

[0049] The above surface roughness may be at least partially attributed to the deposition layer 204 comprising inorganic nanoparticles. For example, such particles may comprise at least one of silica (SiO2) particles, alumina (Al2O3) particles, or alumina (Al2O3)-coated silica (SiO2) particles.

[0050] In certain exemplary embodiments, such particles may have an aspect ratio of less than about 4, such as an aspect ratio of from about 1 to about 4, and further such as an aspect ratio of from about 1 to about 2, and still further such as an aspect ratio in the range of about 1 to about 1.5, and even further such as an aspect ratio in the range of about 1 to about 1.2. For example, such particles may comprise silica (SiO2) particles having an aspect ratio of less than about 4, such as an aspect ratio of from about 1 to about 4, and further such as an aspect ratio of from about 1 to about 2, still further such as an aspect ratio of from about 1 to about 1.5, and still further such as an aspect ratio of from about 1 to about 1.2. As a further example, such particles may comprise alumina (Al2O3) particles having an aspect ratio of less than about 4, such as an aspect ratio ranging from about 1 to about 4, further such as an aspect ratio ranging from about 1 to about 2. Still further, such as an aspect ratio ranging from about 1 to about 1.5, and even further such as an aspect ratio ranging from about 1 to about 1.2.

[0051] In certain exemplary embodiments, such particles may have an aspect ratio greater than about 4, such as an aspect ratio of from about 4 to about 50, and further such as an aspect ratio of from about 4 to about 25, and yet further such as an aspect ratio of from about 4 to about 15, and still further such as an aspect ratio of from about 4 to about 10. For example, such particles may comprise silica (SiO2) particles having an aspect ratio greater than about 4, such as an aspect ratio ranging from about 4 to about 50, further such as an aspect ratio ranging from about 4 to about 25, still further such as an aspect ratio ranging from about 4 to about 15, and still further such as an aspect ratio ranging from about 4 to about 10. As a further example, such particles may include alumina (Al2O3) particles having an aspect ratio greater than about 4, such as an aspect ratio ranging from about 4 to about 50, and further such as an aspect ratio ranging from about 4 to about 25, still further such as an aspect ratio ranging from about 4 to about 15, and still further such as an aspect ratio ranging from about 4 to about 10.

[0052] In certain exemplary embodiments, the substrate 160 may undergo a cleaning step after the above drying step. Specifically, at least one of the first major surface 162 or the second major surface 206 of the substrate 160 may be washed with a liquid wash solution comprising a solvent (such as water or an organic solvent) and at least one solute. In certain exemplary embodiments, the solute may comprise at least one detergent and / or surfactant. In certain exemplary embodiments, the solvent comprises water (e.g., deionized water) and the solute comprises an alkaline detergent, such as a detergent comprising at least one of potassium hydroxide (KOH) or sodium hydroxide (NaOH), commercial examples of which include Semi Clean KG and PK-LCG225X. In certain exemplary embodiments, the solute may be present in the solution at a weight percentage of at least about 0.1%, including at least about 1%, such as from about 0.1% to about 10%, further such as from about 1% to about 5%. In certain exemplary embodiments, the wash solution may be applied at a temperature of at least about 20°C, such as from about 20°C to about 80°C, for a time of at least about 10 seconds, such as from about 10 seconds to about 10 minutes. Additionally, the wash solution may be applied according to methods known to those skilled in the art, including but not limited to spraying, brushing, and dipping. The wash solution may also be applied in an ultrasonic bath according to methods known to those skilled in the art.

[0053] In certain exemplary embodiments, the substrate 160 may undergo a drying step after the above cleaning step. For example, after the cleaning step, the substrate 160 may be dried by using an air knife and / or high-temperature drying known to those skilled in the art. For example, high-temperature drying may be carried out at a temperature of at least about 80°C, such as at least about 120°C, such as from about 80°C to about 400°C, for a time of at least about 10 seconds, such as from about 10 seconds to about 20 minutes. For example, air knife drying may be carried out for a time of at least about 30 seconds, such as from about 30 seconds to about 30 minutes.

[0054] In certain exemplary embodiments, the substrate 160 may also undergo an etching step, such as an alkali etching step or an acid etching step. For example, a solution comprising at least one of hydrofluoric acid (HF), hydrochloric acid (HCl), nitric acid (HNO3), or sodium hydroxide (NaOH) may be applied to the substrate 160 according to methods known to those skilled in the art. For example, the etchant may be present in the solution at a concentration of about 0.1 wt% to about 10 wt% and applied at a temperature of about 20°C to about 60°C for a time of about 10 seconds to about 10 minutes. The etchant may remove at least part or all of the deposited layer 204 comprising inorganic nanoparticles from the substrate 160.

[0055] Embodiments disclosed herein may include embodiments in which the deposited layer 204 is not sintered. Embodiments disclosed herein may also include those embodiments in which the deposited layer 204 does not melt. Additionally, embodiments disclosed herein may include embodiments in which the deposited layer 204 is not under compressive stress. Embodiments disclosed herein may further include embodiments in which the deposited layer 204 does not contain a significant amount (e.g., greater than 1 wt%) of glass, metal, and / or organic compounds (e.g., adhesives, etc.). Additionally, embodiments disclosed herein may include embodiments in which no wet or dry etching steps (such as wet or dry acid etching steps) are performed on the glass sheet 62 prior to applying the deposited layer 204.

[0056] In certain exemplary embodiments, the thickness of the substrate 160 between the first major surface 162 and the second major surface 206 may be less than about 100 micrometers (μm), such as from about 20 μm to about 100 μm, and further such as from about 40 μm to about 80 μm.

[0057] Embodiments disclosed herein may be used with a variety of glass compositions. For example, such compositions may include glass compositions such as an alkali-free glass composition that contains 58 - 65 weight percent (wt%) SiO2, 14 - 20 wt% Al2O3, 8 - 12 wt% B2O3, 1 - 3 wt% MgO, 5 - 10 wt% CaO, and 0.5 - 2 wt% SrO. Such compositions may also include glass compositions such as an alkali-free glass composition that contains 58 - 65 wt% SiO2, 16 - 22 wt% Al2O3, 1 - 5 wt% B2O3, 1 - 4 wt% MgO, 2 - 6 wt% CaO, 1 - 4 wt% SrO, and 5 - 10 wt% BaO. Such compositions may further include glass compositions such as an alkali-free glass composition that contains 57 - 61 wt% SiO2, 17 - 21 wt% Al2O3, 5 - 8 wt% B2O3, 1 - 5 wt% MgO, 3 - 9 wt% CaO, 0 - 6 wt% SrO, and 0 - 7 wt% BaO. Such compositions may additionally include glass compositions such as an alkali-containing glass composition that contains 55 - 72 wt% SiO2, 12 - 24 wt% Al2O3, 10 - 18 wt% Na2O, 0 - 10 wt% B2O3, 0 - 5 wt% K2O, 0 - 5 wt% MgO, and 0 - 5 wt% CaO, and in certain embodiments, it may further include 1 - 5 wt% K2O and 1 - 5 wt% MgO.

[0058] Figure 6Shows a side perspective cross-sectional view of an exemplary encapsulation device 300 that houses multiple substrates according to embodiments disclosed herein. The encapsulation device 300 includes a lid 302, a support member 304, a base 306, a tray 308, and at least one support post 310. The encapsulation device 300 is configured to enclose a plurality of glass sheets located therein.

[0059] In certain exemplary embodiments, the lid 102 may include metal, polymer, polymer composite, and / or metal / polymer laminate. In certain exemplary embodiments, the support member 104, seat 106, tray 108, and / or support post 110 may include metal, such as aluminum or stainless steel, or polymer composite.

[0060] As Figure 6 shown, a plurality of substrates 160 are positioned within the encapsulation device 300 such that each substrate 160 is positioned next to or between adjacent substrates 160. As Figure 6 shown, no interlayer material is provided between adjacent substrates 160 such that each substrate 160 is in direct contact with an adjacent substrate 160.

[0061] Embodiments disclosed herein include embodiments of removing one or more substrates 160 located within the encapsulation device 300 from the encapsulation device 300 (i.e., separating from adjacent substrates 160). After removal from the encapsulation device 300 (and separation from adjacent substrates 160), the substrate 160 may undergo an etching step as described above. The etchant may remove at least a portion or all of the deposited layer 204 containing inorganic nanoparticles from the substrate 160.

[0062] Surface roughness measurement techniques

[0063] As described herein, including the following examples, surface roughness refers to atomic force microscope roughness (AFM Ra) analysis measured using a Hitachi High-Tech AFM5400L. For each sample analyzed, the surface topography image of the AFM was scanned using the Dynamic Force Mode (DFM), where a cantilever SI-DF20P2 (spring constant = 9 N / m, resonance frequency: 100 - 200 kHz, tip radius: 7 nm, tip height: 14 um, lever length: 160 um, lever width: 40 um, lever thickness: 3.5 um) was used. For each sample analyzed, the substrate surface was irradiated with soft X-rays during the measurement, using the following analysis parameters: integral gain (0.2), proportional gain (0.05), Z limit (500 nm), scan area (10 um X 10 um), image quality X-axis (256), and Y-axis (256). The difference between the highest "peak" and the deepest "valley" on the surface (P-V value) was also obtained.

[0064] Zeta potential measurement technique

[0065] As described herein, including the following examples, the zeta potential was measured using an Anton Paar SurPass TM electrokinetic analyzer, using the streaming potential method. The zeta potential was measured at a pH value of 5.5–5.8 (1 mM KCl electrolyte in 18 MΩ water), and then titrated to an acidic pH value by adding 1 mM HCl. As the solution "flows" over a flat surface, this gradually adjusts the solution pH value (in steps of ~0.5). After the pH value reaches approximately 3, the surface is rinsed with 18 MΩ water to bring the pH value back to approximately 5.5 - 5.8, and then similarly titrated to the basic side by adding 1 mM KOH until the pH value reaches approximately 11. The measurement results at a pH value of approximately 4.5 are presented in this application. Throughout the measurement cycle, the glass surface temperature was maintained at approximately 25 °C.

[0066] Binding energy test conditions

[0067] The binding interaction energy (δ) was measured at a fixed displacement using the double cantilever beam (DCB) experimental method. Specifically, a razor blade with a thickness (y) of approximately 253 microns was wedged between two coated glass substrates, which were pre-pressed together. Each glass substrate had a thickness (d) of approximately 75 microns and a Young's modulus (E) of approximately 71.3 GPa. Then, the separation distance (L) between the glass substrates was measured as the perpendicular distance from the edge of the razor blade, and the binding interaction energy (δ) was calculated according to the following formula:

[0068]

[0069] For each data point presented in the following examples, a total of at least three separation distances (L) were measured and then used to calculate the binding interaction energy (δ). The greater the separation distance, the lower the binding interaction energy, and thus the weaker the binding attraction between the glass substrates.

[0070] Examples

[0071] The embodiments disclosed herein will be further described with reference to the following non-limiting examples.

[0072] Example 1:

[0073] A series of solutions containing 0.5 wt% inorganic nanoparticles listed in Table 1 were individually dip-coated onto Eagle On the sample of the glass substrate for about 20 seconds, each substrate having a thickness of about 0.5 mm. Then, the coated substrate was rinsed in deionized water for about 10 seconds, and then washed in an ultrasonic bath containing an aqueous solution containing about 4% by volume of Parker 225X detergent for about 30 seconds. The coated substrate was rinsed again in deionized water for about 30 seconds, and then dried at a temperature of about 90 °C for about 15 minutes. Next, pairs of substrates with the same coating or without coating (control group) were brought into contact with each other, during which a weight of about 2.6 kg was placed on the sample under 11% (low) and 85% (high) relative humidity conditions. Under these conditions, after 4 days and 18 days, the samples were taken out, and a blade with a thickness of about 0.244 mm was inserted between the substrates for separation purposes.

[0074] Table 1

[0075]

[0076]

[0077] Figure 7 is a graph showing the separation energy of the substrate or glass sheet under the conditions of Example 1. As Figure 7 shown, the presence of the layer containing inorganic nanoparticles significantly reduces the binding interaction energy between adjacent substrates, and in most cases, it is reduced by more than about 50% compared to the control sample without coating the layer containing inorganic nanoparticles.

[0078] For example, the embodiments disclosed herein include embodiments where when the binding energy test conditions are carried out for 4 days, the binding interaction energy between adjacent substrates is less than about 150 millijoules per meter (mJ / m), such as less than about 100 millijoules per meter (mJ / m), and further such as less than about 150 millijoules per meter (mJ / m), such as from about 25 millijoules per meter (mJ / m) to about 150 millijoules per meter (mJ / m), and further, such as from about 50 millijoules per meter (mJ / m) to about 100 millijoules per meter (mJ / m).

[0079] In addition, the embodiments disclosed herein include embodiments where when the binding energy test conditions are carried out for 18 days, the binding interaction energy between adjacent substrates is less than about 200 millijoules per meter (mJ / m), such as less than about 150 millijoules per meter (mJ / m), and further such as less than about 100 millijoules per meter (mJ / m), such as from about 50 millijoules per meter (mJ / m) to about 200 millijoules per meter (mJ / m), and further, such as from about 100 millijoules per meter (mJ / m) to about 150 millijoules per meter (mJ / m).

[0080] Figure 8 is a graph showing the contact angles of the substrate or glass sheet with water and diiodomethane under the conditions of Example 1. As Figure 8 shown, the presence of the layer containing inorganic nanoparticles significantly increases the water contact angle of the substrate with the layer containing inorganic nanoparticles, and in most cases, it increases by more than about 100% compared to the control sample without the layer coated with inorganic nanoparticles.

[0081] For example, the embodiments disclosed herein include those embodiments in which the substrate with the layer containing inorganic nanoparticles has a water contact angle greater than about 5 degrees, such as greater than about 10 degrees, including water contact angles from about 5 degrees to about 15 degrees, and further including those with water contact angles from about 10 degrees to about 15 degrees.

[0082] Figure 9 is a graph showing the Zeta potential of the substrate or glass sheet under the conditions of Example 1. As Figure 9 shown, the presence of the layer containing inorganic nanoparticles reduces the Zeta potential of the substrate with the layer containing inorganic nanoparticles compared to the control sample without the layer coated with inorganic nanoparticles.

[0083] For example, the embodiments disclosed herein include those embodiments in which the substrate with the layer containing inorganic nanoparticles has a Zeta potential less than about -32 millivolts (mV) at a pH of 4.5, such as a Zeta potential less than about -36 mV, and further such as a Zeta potential less than about -40 mV, including those with Zeta potentials from about -32 mV to -42 mV.

[0084] The embodiments disclosed herein include a substrate having a layer containing inorganic nanoparticles deposited on at least one of its major surfaces, and the layer has a surface roughness of about 0.3 nanometers to about 3 nanometers, such as about 0.3 nanometers to about 1.5 nanometers, and further such as from about 0.3 nanometers to about 0.8 nanometers. For example, a glass sheet subjected to the conditions of Example 1 (wherein the inorganic nanoparticles containing ST-S are deposited on Eagle the major surface of the glass) is found to have a surface roughness of about 0.3 to about 0.8 nanometers on that surface. As another example, a glass sheet subjected to the conditions of Example 1 (wherein the inorganic nanoparticles containing ST-AK are deposited on Eagle the major surface of the glass) is found to have a surface roughness of about 0.5 nanometers on that surface. As a further example, a glass sheet subjected to the conditions of Example 1 (wherein the inorganic nanoparticles containing AS-200 are deposited on Eagle A glass sheet on the main surface of the glass was found to have a surface roughness of about 0.6 to about 0.8 nanometers on this surface.

[0085] Example 2

[0086] By dip-coating samples for 20 and 120 seconds with nanoparticle solutions containing 0.5% and 2.5% of AS-200, ST-AK, and ST-S as described in Table 1, a coating containing an inorganic nanolayer was deposited on a Eagle glass substrate with a thickness of about 100 micrometers. Then the samples were processed and subjected to the load contact conditions as described in Example 1. Then the coated samples and the control sample solution were etched in a solution containing about 10% HF and about 5% HNO3 for 4 minutes to remove a sheet thickness of about 40 micrometers. Subsequently, the samples were rinsed with deionized water and then sonicated in deionized water for about 3 minutes. Shadow images were obtained to observe potential defects caused by the inorganic nanolayer on the glass surface.

[0087] Figure 10 is a graph showing the separation energy of the substrate or glass sheet that has undergone the conditions of Example 2 after the load contact conditions and before the etching step. As Figure 10 shown, compared with the control samples without a layer containing inorganic nanoparticles coated, the presence of the inorganic nanolayer results in a reduction of the interfacial binding energy between adjacent substrates by about 60 - 80%.

[0088] Furthermore, the surface quality of the coated samples was observed to be similar to that of the control samples after acid etching, indicating that no defects were introduced due to the nanolayer. In particular, the acid solution has the potential to completely dissolve the nanolayer without leaving a heterogeneous surface morphology, thus eliminating potential surface defects such as streaks and Mura. Therefore, coating an inorganic nanolayer on a glass substrate (such as an ultra-thin glass substrate) can serve as a sheet protection method while facilitating the separation between sheets, potentially eliminating the need for an interlayer material between adjacent substrates during transportation and storage.

[0089] Although the above embodiments have been described with reference to the fusion down draw process, it should be understood that such embodiments are also applicable to other glass forming methods such as the float process, the slot draw process, the up draw process, tube drawing processes, and press-rolling processes.

[0090] The embodiments disclosed herein also include electronic devices comprising any of the substrates disclosed herein.

[0091] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments of the present disclosure without departing from the spirit and scope of the present disclosure. Accordingly, the present disclosure is intended to cover such modifications and variations that fall within the scope of the appended claims and their equivalents.

Claims

1. A substrate, comprising: A glass sheet including a first major surface and an opposite second major surface extending in a direction parallel to the first major surface; A layer including inorganic nanoparticles deposited on at least one of the first major surface and the second major surface, the layer having a surface roughness of 0.3 nanometers to 3 nanometers and a water contact angle greater than 5 degrees.

2. The substrate according to claim 1, wherein the layer has a zeta potential less than -32 mV at a pH value of 4.

5.

3. The substrate according to claim 1, wherein the layer includes silica (SiO2) particles.

4. The substrate according to claim 3, wherein the silica (SiO2) particles have an aspect ratio of 1 to 4.

5. The substrate according to claim 3, wherein the silica (SiO2) particles have an aspect ratio greater than 4.

6. The substrate according to claim 1, wherein the layer includes alumina (Al2O3) particles.

7. The substrate according to claim 6, wherein the alumina (Al2O3) particles have an aspect ratio of 1 to 4.

8. The substrate according to claim 6, wherein the alumina (Al2O3) particles have an aspect ratio greater than 4.

9. The substrate according to claim 1, wherein the layer includes alumina (Al2O3)-coated silica (SiO2) particles.

10. The substrate according to claim 1, wherein the glass sheet has a thickness between the first major surface and the second major surface of less than 100 micrometers.

11. The substrate according to claim 1, wherein the glass sheet includes a non-alkali glass composition comprising 58 - 65 wt% SiO2, 14 - 20 wt% Al2O3, 8 - 12 wt% B2O3, 1 - 3 wt% MgO, 5 - 10 wt% CaO, and 0.5 - 2 wt% SrO.

12. The substrate according to claim 1, wherein the glass sheet includes a non-alkali glass composition comprising 58 - 65 wt% SiO2, 16 - 22 wt% Al2O3, 1 - 5 wt% B2O3, 1 - 4 wt% MgO, 2 - 6 wt% CaO, 1 - 4 wt% SrO, and 5 - 10 wt% BaO.

13. The substrate according to claim 1, wherein the glass sheet includes a non-alkali glass composition comprising 57 - 61 wt% SiO2, 17 - 21 wt% Al2O3, 5 - 8 wt% B2O3, 1 - 5 wt% MgO, 3 - 9 wt% CaO, 0 - 6 wt% SrO, and 0 - 7 wt% BaO.

14. The substrate according to claim 1, wherein the glass sheet includes a glass composition comprising 55 - 72 wt% SiO2, 12 - 24 wt% Al2O3, 10 - 18 wt% Na2O, 0 - 10 wt% B2O3, 0 - 5 wt% K2O, 0 - 5 wt% MgO, and 0 - 5 wt% CaO, 1 - 5 wt% K2O, and 1 - 5 wt% MgO.

15. An electronic device, comprising the substrate according to claim 1.

16. A method of processing the substrate according to claim 1, comprising positioning the substrate between adjacent substrates according to claim 1.

17. The method according to claim 16, wherein when subjected to the binding energy test conditions for 4 days, the binding interaction energy between adjacent substrates is less than 150 millijoules per meter (mJ / m).

18. The method according to claim 16, wherein when subjected to the binding energy test conditions for 18 days, the binding interaction energy between adjacent substrates is less than 200 millijoules per meter (mJ / m).

19. The method according to claim 16, wherein the method further comprises separating the substrate according to claim 1 from an adjacent substrate according to claim 1, and removing at least a portion of the layer from the substrate according to claim 1.

20. The method according to claim 19, wherein removing at least a portion of the layer comprises introducing the substrate according to claim 1 into a solution comprising at least one of hydrofluoric acid (HF), hydrochloric acid (HCl), nitric acid (HNO3), or sodium hydroxide (NaOH).

Images