WO2021086337A1

WO2021086337A1 - Protective panels with anti-glare ceramic coatings

Info

Publication number: WO2021086337A1
Application number: PCT/US2019/058691
Authority: WO
Inventors: Hui He; Hang Yan YUEN; Kuan-Ting Wu
Original assignee: Hewlett-Packard Development Company L.P.
Priority date: 2019-10-30
Filing date: 2019-10-30
Publication date: 2021-05-06
Also published as: TW202116555A; TWI753516B

Abstract

In one example, a protective panel may include a glass substrate and an anti-glare ceramic coat formed on a surface of the glass substrate. Example anti-glare ceramic coat may include a sol-gel composition. Further, the protective panel may include an anti-fingerprint coat formed on the anti-glare ceramic coat.

Description

PROTECTIVE PANELS WITH ANTI-GLARE CERAMIC COATINGS

BACKGROUND

[0001] Display devices such as a liquid crystal display, a plasma display, an organic electroluminescence (EL) display, an inorganic EL display, and a field emission display (FED) may have an anti-glare layer that is disposed on an outermost surface of a display. The anti-glare layer may reduce an amount of light that reflects off the display using the principle of optical interference. Such displays may include a display panel and a protective panel attached to an outermost surface of the display panel.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Examples are described in the following detailed description and in reference to the drawings, in which:

[0003] FIG. 1 illustrates a cross-sectional side view of an example protective panel, depicting an anti-glare ceramic coat and an anti-fingerprint coat;

[0004] FIG. 2A illustrates a cross-sectional side view of an example electronic device including a display module and a protective panel;

[0005] FIG. 2B illustrates a cross-sectional side view of the example electronic device of FIG. 2A, depicting additional features;

[0006] FIG. 3 illustrates an example flowchart for making a protective panel;

[0007] FIG. 4 illustrates another example flowchart for making a protective panel; and

[0008] FIG. 5 illustrates yet another example flowchart for making a protective panel. DETAILED DESCRIPTION

[0009] An anti-glare treatment may be used on an outermost surface of a display (e.g., a liquid crystal display) for inhibiting reflection of an exterior light. The anti-glare treatment may use a chemical etching process on a surface of a glass substrate (i.e., a cover glass) to create an anti-glare effect. For example, the chemical etching process may form an uneven structure on the surface of the display to have effects on scattering of a reflected light from the surface and blurring of a reflected image on the surface.

[0010] Chemical etching may facilitate bonding at an interface of an anti- glare coat and the glass substrate. However, chemical etching process for forming the anti-glare layer on the glass substrate may include a significant running cost and a low production yield rate (e.g., 20-35%), during manufacturing. For example, chemical etching process for forming the anti-glare layer may take about 50-60 minutes to achieve > 20% haze with a production yield rate of 20-35%, which can result in the significant running cost. Also, a significantly high haze with less transparency may impact light-emitting diode (LED) lightings of the display and hence additional LED lightings may have to be installed in the display.

[0011] Examples described herein may provide a protective panel with an anti-glare ceramic coating. The protective panel may include a glass substrate and an anti-glare ceramic coat formed on a surface of the glass substrate. Example anti-glare ceramic coat may include a sol-gel composition. Further, the protective panel may include an anti-fingerprint coat formed on the anti-glare ceramic coat. The anti-fingerprint coat may provide the protective panel with an anti-smudge surface finish.

[0012] Thus, examples described herein may enhance the production yield rate by using a sol-gel derived anti-glare coating process on the glass substrate. Further, the protective panel with the anti-glare ceramic coat may provide a transparency greater than or equal to 98% and a refractive index in a range of 2.3- 2.6. Furthermore, the transparent anti-glare ceramic coat formed herein may not impact LED lightings of the display and hence no additional LED lightings may have to be installed in the display. [0013] In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present techniques. It will be apparent, however, to one skilled in the art that the present apparatus, devices and systems may be practiced without these specific details. Reference in the specification to “an example” or similar language means that a particular feature, structure, or characteristic described is included in at least that one example, but not necessarily in other examples.

[0014] Turning now to the figures, FIG. 1 illustrates a cross-sectional side view of an example protective panel 100, depicting an anti-glare ceramic coat 104 and an anti-fingerprint coat 106. Example protective panel 100 may be a tempered glass, a touch panel, or an outermost surface of a display device. In other examples, protective panel 100 may be disposed on a display having the touch panel.

[0015] As shown in FIG. 1, example protective panel 100 may include a glass substrate 102. Example glass substrate 102 may have a thickness in a range of 0.2 mm to 0.7 mm. Further, protective panel 100 may include anti-glare ceramic coat 104 formed on a surface of glass substrate 102. In one example, anti-glare ceramic coat 104 may include a sol-gel composition. Example sol-gel composition may include alkoxides of lead-lanthanum-zirconium-titanium (PLZT), alkoxides of lead-zirconate-titanate (PZT), alkoxides of barium titanate (BaTiO₃), alkoxides of bismuth titanate (Bi₄Ti₃O₁₂), alkoxides of strontium titanate (SrTiO₃), alkoxides of calcium titanate (CaTiO₃), alkoxides of lanthanum titanate (LaTiO₃), or any combination thereof. In one example, anti-glare ceramic coat 104 may have a thickness in a range of 30 nm to 15 μm.

[0016] Furthermore, protective panel 100 may include anti-fingerprint coat 106 formed on anti-glare ceramic coat 104. In one example, anti-fingerprint coat 106 may have a thickness in a range of 10 nm to 100 nm. Example anti-fingerprint coat 106 may prevent fingerprint pollution (e.g., fingerprint generation on a touch screen) on an upper surface of anti-glare ceramic coat 104. In other examples, anti-fingerprint coat 106 may prevent external pollutants from being attached to the upper surface of anti-glare ceramic coat 104 and facilitate easy clean of the upper surface of anti-glare ceramic coat 104.

[0017] FIG. 2A illustrates a cross-sectional side view of an example electronic device 200 including a display module 202 and a protective panel 204. Example electronic device 200 can include a notebook computer, personal computer (PC), tablet computer, smartphone, audio and video devices (e.g., stereo equipment and televisions), or the like. As shown in FIG. 2A, electronic device 200 may include display module 202 including a display area. The display area may be configured to display an image.

[0018] Further, electronic device 200 may include protective panel 204 disposed on an outer surface of display module 202. Example protective panel 204 may be a touch panel or a tempered glass used for the touch panel. Further, protective panel 204 may be disposed on the outer surface of display module 202 using a resin, which may be an optically clear adhesive. In one example, protective panel 204 may include a glass substrate 206 and an anti-glare ceramic coat 208 formed on a surface of glass substrate 206 to cover the display area. Anti-glare ceramic coat 208 may prevent glaring effects during viewing of a display screen of display module 202.

[0019] Example anti-glare ceramic coat 208 may include a sol-gel composition. The sol-gel composition may include alkoxides of lead-lanthanum- zirconium-titanium (PLZT), lead-zirconium-titanium (PZT), or lanthanum-titanium. Example alkoxides may be selected from a group consisting of lead isopropoxide, lanthanum isopropoxide, zirconium isopropoxide, and titanium isopropoxide.

[0020] In one example, the sol-gel composition may include a combination of lead isopropoxide, lanthanum isopropoxide, zirconium isopropoxide, and titanium isopropoxide. In another example, the sol-gel composition may include a combination of lead isopropoxide, zirconium isopropoxide, and titanium isopropoxide. In yet another example, the sol-gel composition may include a combination of lanthanum isopropoxide and titanium isopropoxide. [0021] FIG. 2B illustrates a cross-sectional side view of example electronic device 200 of FIG. 2A, depicting additional features. For example, similarly named elements of FIG. 2B may be similar in structure and/or function to elements described with respect to FIG. 2A. As show in FIG. 2B, example electronic device 200 may include an anti-fingerprint coat 210 formed on anti-glare ceramic coat 208. In one example, the anti-fingerprint coat may include dodecyltrimethoxysilane, mecaptoundecyltrimethoxysilane, triethoxysilylundecanal 11- aminoundecyltriethoxysilane, N-(2-aminoethyl)-11-undecyltrimethoxysilane, long chain silane, or any combination thereof.

[0022] FIG. 3 illustrates an example flowchart 300 for making a protective panel. At 302, an anti-glare ceramic coating may be applied on a surface of a glass substrate using a sol-gel process. In one example, applying the anti-glare ceramic coating on the surface of the glass substrate using the sol-gel process may include applying the anti-glare ceramic coating on the surface of the glass substrate by one of a sol-gel spin-coating, sol-gel roller-coating, and a sol-gel spray-coating. Example anti-glare ceramic coating may be formed from a sol-gel composition.

[0023] For example, the sol-gel composition may include a precursor, a solvent, an acid catalyst, and deionized water. An example sol-gel composition may include:

Mixing the precursor in the solvent. Example precursor may include lead-lanthanum-zirconium-titanium (PLZT), lead-zirconate- titanate (PZT), barium titanate (BaTiO₃), bismuth titanate (Bi₄Ti₃O₁₂), strontium titanate (SrTiO₃), calcium titanate (CaTiO₃), lanthanum titanate (LaTiO₃), or any combination thereof. Example solvent may include isopropanol, ethanol, methanol, butanol, or any combination thereof.

Further, 0.01-0.1 weight percentage of the acid catalyst may be added to the mixture of the precursor and the solvent. Example acid catalyst may include carbonic acid, hydrochloric acid, nitric acid, oxalic acid, citric acid, acetic acid, trifluoroacetic acid, formic acid, or any combination thereof. Furthermore, 0.1 -0.2 weight percentage of the deionized water may be added for hydrolysis to form the sol-gel composition.

[0024] In another example, the sol-gel composition may include making a first solution by mixing a first precursor (e.g., lanthanum) with the solvent. Further, a second precursor (e.g., lead) may be added to the first solution to form a second solution. Then, a third precursor (e.g., titanium) may be added to the second solution to form a third solution. Further, a fourth precursor may be added to the third solution to form a fourth solution. Furthermore, the acid catalyst and the deionized water may be added to the fourth solution and stirred for about 30 minutes and for aging time of about 60 minutes. The sol-gel composition thus formed may be applied on the surface of the glass substrate.

[0025] In some examples, the glass substrate may be cleaned prior to applying the anti-glare ceramic coating. For example, cleaning the glass substrate may include ultrasonic cleaning, plasma cleaning, or a combination thereof. At 304, the anti-glare ceramic coating formed on the surface may be cured. Example antiglare ceramic coat applied on the cover glass may be cured at a temperature in a range of 80-500°C for about 15-90 minutes. At 306, an anti-fingerprint coating may be applied on the anti-glare ceramic coating. In one example, the anti-fingerprint coating may include dodecyltrimethoxysilane mecaptoundecyltrimethoxysilane, triethoxysilylundecanal, 11-aminoundecyitriethoxysilane, N-(2-aminoethyl)-11- undecyltrimethoxysilane, long chain silane, or any combination thereof. At 308, the anti-fingerprint coating formed on the anti-glare ceramic coating may be cured to form the protective panel. In one example, the anti-fingerprint coating may be cured at a temperature in a range of 80-200°C for about 10-30 minutes.

[0026] FIG. 4 illustrates another example flowchart 400 for making a protective panel. At 402, a cover glass or glass substrate, having a first surface and a second surface opposite to the first surface, may be provided. At 404, the cover glass may be cleaned using an ultrasonic cleaning. Example ultrasonic cleaning may use ultrasound (e.g., 20-400 kHz) and deionized water with a surfactant to clean debris on the cover glass. At 406, the cover glass may be further cleaned, for instance, using a plasma cleaning. Example plasma cleaning may refer to a process of removing organic matter from the cover glass through the use of an ionized gas called plasma. Plasma cleaning may be performed in a vacuum chamber utilizing gases such as oxygen, argon gas, tetrafluoromethane (CF4), sulfur hexafluoride (SFe), and nitrogen trifluoride (NF3), and/or the like.

[0027] At 408, an anti-glare ceramic coat may be applied on the cover glass. In one example, the anti-glare ceramic coat may be applied on the first surface of the cover glass using a sol-gel process. Example sol-gel process may include a screen-printing deposition, slit-coating deposition, roller-coating deposition, spincoating deposition, spray-coating deposition, brush-coating deposition, wetcoating deposition, or the like. At 410, the anti-glare ceramic coat applied on the cover glass may be cured at a temperature in a range of 80-500°C for about 15-90 minutes to form the protective panel. In other examples, the second surface of the glass substrate may be attached to an outer surface of a display or a touch panel, for instance, using an optically clear adhesive.

[0028] FIG. 5 illustrates yet another example flowchart 500 for making a protective panel. At 502, a cover glass or glass substrate, having a first surface and a second surface opposite to the first surface, may be provided. At 504, the cover glass may be cleaned using an ultrasonic cleaning. At 506, the cover glass may be further cleaned, for instance, using a plasma cleaning.

[0029] At 508, an anti-glare ceramic coat may be applied (e.g., spray coated, roller coated, or spin coated) on the first surface of the cover glass. At 510, the anti-glare ceramic coat applied on the first surface of the cover glass may be cured at a temperature in a range of 80-500°C for about 15-90 minutes. At 512, an antifingerprint layer may be coated (e.g., spray coated, roller coated, or spin coated) on the anti-glare layer. At 514, the anti-fingerprint layer may be cured at a temperature in a range of 80-200°C for about 10-30 minutes to form the protective panel. The protective panel may be attached to an outer surface of a display or a touch panel, for instance, through the second surface of the glass substrate.

[0030] Even though FIGs. 1-5 describe about applying an anti-glare ceramic coat on a glass substrate and then an anti-fingerprint coat on the anti-glare ceramic coat, examples described herein can also be applicable for other layers that can be formed on the glass substrate, such as an anti-reflection coating.

[0031] It should be understood that example flowcharts 300, 400, and 500 represent generalized illustrations, and that other processes may be added, or existing processes may be removed, modified, or rearranged without departing from the scope and spirit of the present application. Further, example flowcharts 300, 400, and 500 may not intended to limit the implementation of the present application, but rather example flowcharts 300, 400, and 500 illustrate functional information to design/fabricate circuits, generate machine-readable instructions, or use a combination of hardware and machine-readable instructions to perform the illustrated processes.

[0032] It may be noted that the above-described examples of the present solution are for the purpose of illustration only. Although the solution has been described in conjunction with a specific implementation thereof, numerous modifications may be possible without materially departing from the teachings and advantages of the subject matter described herein. Other substitutions, modifications and changes may be made without departing from the spirit of the present solution. All of the features disclosed in this specification (including any accompanying claims, abstract, and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

[0033] The terms “include,” “have,” and variations thereof, as used herein, have the same meaning as the term “comprise" or appropriate variation thereof. Furthermore, the term “based on”, as used herein, means “based at least in part on.” Thus, a feature that is described as based on some stimulus can be based on the stimulus or a combination of stimuli including the stimulus.

[0034] The present description has been shown and described with reference to the foregoing examples. It is understood, however, that other forms, details, and examples can be made without departing from the spirit and scope of the present subject matter that is defined in the following claims.

Claims

WHAT IS CLAIMED IS:

1. A protective panel comprising: a glass substrate; an anti-glare ceramic coat formed on a surface of the glass substrate, the anti-glare ceramic coat comprising a sol-gel composition; and an anti-fingerprint coat formed on the anti-glare ceramic coat.

2. The protective panel of claim 1 , wherein the sol-gel composition comprises alkoxides of lead-lanthanum-zirconium-titanium (PLZT), alkoxides of lead- zirconate-titanate (PZT), alkoxides of barium titanate (BaTiO₃), alkoxides of bismuth titanate (Bi₄Ti₃O₁₂), alkoxides of strontium titanate (SrTiO₃), alkoxides of calcium titanate (CaTiO₃), alkoxides of lanthanum titanate (LaTiO₃), or any combination thereof.

3. The protective panel of claim 1 , wherein the glass substrate has a thickness in a range of 0.2 mm to 0.7 mm.

4. The protective panel of claim 1 , wherein the anti-glare ceramic coat has a thickness in a range of 30 nm to 15 μm.

5. The protective panel of claim 1 , wherein the anti-fingerprint coat has a thickness in a range of 10 nm to 100 nm.

6. An electronic device comprising: a display module including a display area; and a protective panel disposed on an outer surface of the display module, the protective panel comprising: a glass substrate; and an anti-glare ceramic coat formed on a surface of the glass substrate to cover the display area, the anti-glare ceramic coat comprising a sol-gel composition.

7. The electronic device of claim 6, further comprising: an anti-fingerprint coat formed on the anti-glare ceramic coat.

8. The electronic device of claim 6, wherein the protective panel is one of a tempered glass and a touch panel.

9. The electronic device of claim 6, wherein the sol-gel composition comprises alkoxides of lead-lanthanum-zirconium-titanium (PLZT), lead-zirconium-titanium (PZT), or lanthanum-titanium, and wherein the alkoxides are selected from a group consisting of lead isopropoxide, lanthanum isopropoxide, zirconium isopropoxide, and titanium isopropoxide.

10. A method for making a protective panel, comprising: applying an anti-glare ceramic coating on a surface of a glass substrate using a sol-gel process; curing the anti-glare ceramic coating formed on the surface; applying an anti-fingerprint coating on the anti-glare ceramic coating; and curing the anti-fingerprint coating formed on the anti-glare ceramic coating to form the protective panel.

11. The method of claim 10, wherein applying the anti-glare ceramic coating on the surface of the glass substrate using the sol-gel process comprises: applying the anti-glare ceramic coating on the surface of the glass substrate by one of a sol-gel spin-coating, sol-gel roller coating, and a sol-gel spray-coating.

12. The method of claim 10, wherein the anti-glare ceramic coating is formed from a sol-gel composition comprising a precursor, a solvent, an acid catalyst, and deionized water.

13. The method of claim 12, wherein the precursor comprises lead-lanthanum- zirconium-titanium (PLZT), lead-zirconate-titanate (PZT), barium titanate (BaTiO₃), bismuth titanate (Bi₄Ti₃O₁₂), strontium titanate (SrTiO₃), calcium titanate (CaTiO₃), lanthanum titanate (LaTiO₃), or any combination thereof.

14. The method of claim 10, wherein the anti-fingerprint coating comprises dodecyltrimethoxysilane, mecaptoundecyltrimethoxysilane, triethoxysilylundecanal, 11-aminoundecyltriethoxysilane, N-(2-aminoethyl)-11- undecyltrimethoxysilane, long chain silane, or any combination thereof.

15. The method of claim 10, further comprising: cleaning the glass substrate prior to applying the anti-glare ceramic coating, wherein cleaning the glass substrate comprises ultrasonic cleaning, plasma cleaning, or a combination thereof.