Multi-layer wet-dry hard coating including dual-sided wet hard coating for flexible cover lens structures, and related methods and coating systems

Abstract

Embodiments of the present disclosure are directed to flexible display devices including a dual-sided wet hard coating for flexible cover lens structures, and related methods and coating systems. The flexible cover lens film has beneficial strength, elasticity, optical transmittance, and abrasion resistance properties. In one or more embodiments, a cover lens structure for a display device includes a substrate layer including a first side and a second side. The cover lens structure includes a first wet hard coating layer deposited on a first side of the substrate layer, and a second wet hard coating layer deposited on a second side of the substrate layer. The cover lens structure includes one or more adhesion promoting layers formed over the second side, and a dry hard coating layer formed over the second side.

Description

background Technical Field

[0002] Embodiments of the present disclosure relate to flexible display devices including double-sided wet hard coatings for flexible cover lens structures, and related methods and coating systems. Background Art

[0003] Electronic devices often have displays such as liquid crystal displays (LCDs), organic light emitting-diode (OLED) displays, and quantum dot (QD) displays. Such displays can be fragile and sensitive to moisture, pressure, and / or particle contamination. In general, display devices use several layers of optics to color, polarize, and shutter the light from an illumination source. To prevent damage to underlying films, a rigid display cover lens layer is mounted above the other layers to prevent damage to underlying films. Including a rigid display cover lens can add undesirable weight to the electronic device.

[0004] The cover lens may also be hampered with respect to optical device performance (e.g., the cover lens may have limited light transmittance and turbidity), flexibility (e.g., fracture or plastic deformation at a critical strain), and / or mechanical properties (such as hardness and impact resistance). For example, the cover lens may be sensitive to temperature and may exhibit increased particle migration and / or increased turbidity. As an example, the cover lens may have oligomer migration. Replacing the cover lens may involve expertise, time, and significant expense.

[0005] Thus, there is a need for a display cover lens having reduced haze, mitigated oligomer migration, high hardness, high optical transmittance, high elasticity, beneficial mechanical properties, and anti-abrasion properties. Summary of the invention

[0006] Embodiments of the present disclosure are directed to flexible display devices including double-sided wet hard coatings for flexible cover lens structures, and related methods and coating systems. The flexible cover lens film has beneficial strength, elasticity, optical transmittance, and anti-abrasion properties.

[0007] In one or more embodiments, a cover lens structure for a display device includes a substrate layer including a first side and a second side. The cover lens structure includes a first wet hard coating layer deposited on the first side of the substrate layer, and a second wet hard coating layer deposited on the second side of the substrate layer. The cover lens structure includes one or more adhesion promoting layers formed on the second side, and a dry hard coating layer formed on the second side.

[0008] In one or more embodiments, a method of forming a cover lens structure includes depositing a first hard coating layer on a first side of a substrate layer using a first wet deposition process, and depositing a second hard coating layer on a second side of the substrate layer using a second wet deposition process. The method includes depositing one or more adhesion promoting layers on the second side, and depositing a third hard coating layer on the second side using a dry deposition process. The method includes depositing an anti-fouling layer on the second side, and arranging a cover lens structure to position the first hard coating layer on a touch panel and a display structure of a display device.

[0009] In one or more embodiments, a coating system includes a first rotatable rod configured to receive a first storage roll, and a second rotatable rod configured to receive a second storage roll. The coating system includes a plurality of transfer rollers disposed along a transfer path between the first storage roll and the second storage roll, and a coating module interfaced with a first section of the transfer path. The coating module includes one or more of the following: a rod, a slot die, one or more comma rollers, a micro-gravure, a gravure, one or more casting nozzles, one or more casting rollers, or one or more spray nozzles. The coating system includes a curing module interfaced with a second section of the transfer path. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to be able to understand in detail the manner in which the above-mentioned features of the present disclosure are used, a more particular description of the present disclosure briefly summarized above may be made with reference to the embodiments, some of which are shown in the accompanying drawings. However, it should be noted that the accompanying drawings only illustrate common embodiments of the present disclosure and are therefore not to be considered limiting in scope, as the present disclosure may admit of other equally effective embodiments.

[0011] Figure 1A is a schematic cross-sectional view of a display device according to one or more embodiments.

[0012] Figure 1B is a schematic cross-sectional view of a display device according to one or more embodiments.

[0013] FIG. 2A to FIG. 2E are schematic cross-sectional views of flexible cover lens films according to one or more embodiments, respectively.

[0014] Figure 3 is a schematic cross-sectional view of an exemplary embodiment of a flexible cover lens film including a double-stacked multi-layer hard coating layer and a double-stacked first wet hard coating layer of the flexible cover lens film according to one or more embodiments.

[0015] Figure 4A is a schematic plan view of a coating system during a first wet deposition process according to one or more embodiments.

[0016] Figure 4B is a schematic plan view of a coating system during a second wet deposition process according to one or more embodiments.

[0017] Figure 5 is a schematic block diagram illustration of a method of forming a cover lens structure according to one or more embodiments.

[0018] To facilitate understanding, identical reference numerals have been used, where possible, to identify identical components that are common to the figures. It is contemplated that components and features of one embodiment may be beneficially incorporated in other embodiments without further recitation. DETAILED DESCRIPTION

[0019] Embodiments of the present disclosure relate to flexible display devices including double-sided wet hard coatings for flexible cover lens structures, and related methods and coating systems. The flexible cover lens film has beneficial strength, elasticity, optical transmittance and anti-abrasion properties. The flexible cover lens film has beneficial strength, elasticity, optical transmittance and anti-abrasion properties. The flexible cover lens film includes a hard coating layer, a multilayer hard coating layer, and a substrate layer. The substrate layer may have a thickness of 2 μm to 100 μm, and the multilayer hard coating layer may have a thickness of 1 μm to 30 μm, such as 1 μm to 10 μm. The hard coating layer is deposited using a first wet deposition process. The multilayer hard coating layer includes a second hard coating layer deposited using a second wet deposition process, a third hard coating layer deposited using a dry deposition process, and one or more adhesion promoting layers. The substrate layer is double-sided, so that the hard coating layer is disposed on a first side of the substrate layer, and the second hard coating layer is disposed on a second side of the substrate layer. In terms of optical properties, the flexible cover lens has a total transmittance greater than 88%, a haze of about 1% or less, and a yellowness index of b*<1. By combining wet and dry deposition processes to form a multi-layer hard coating, the cover lens film is flexible and strong with a hardness of 3H to 9H.

[0020] Figure 1A is a schematic cross-sectional view of a display device 100 according to one or more embodiments.

[0021] Figure 1B is a schematic cross-sectional view of a display device 150 according to one or more embodiments.

[0022] Figure 1A The display device 100 and Figure 1BThe display device 150 includes the same layers; however, the layers of each display device 100, 150 are in a different order. The display devices 100, 150 can be manufactured using roll-to-roll deposition, plasma enhanced chemical vapor deposition, chemical vapor deposition, physical vapor deposition, atomic layer deposition, photolithography, etching, and / or other such suitable manufacturing processes. Suitable manufacturing equipment from Applied Materials, Inc. of Santa Clara, California can be used. Other manufacturing equipment can be used.

[0023] The display devices 100 and 150 each include a cover lens film 102, a film layer 104, a touch panel 106, a display structure 108, a substrate 110, and a shielding layer 112. The cover lens film 102 can be bonded to a foldable glass substrate (e.g., ultra-thin glass). Figure 1A In an embodiment, the film layer 104 is between the cover lens film 102 and the touch panel 106. In one or more embodiments, the film layer 104 is a multifunctional film layer including a polarizing film. The film layer 104 (such as a polarizing film) is used to reduce the undesired reflection of the reflective metal attributable to the electrode lines or metal structures constituting the display device 100. The film layer 104 may include a quarter-wave retarder and a linear polarizer formed by a flexible lens film, such as a flexible lens film having a thickness of less than 0.2 mm. The cover lens film 102 can be bonded to the film layer 104 and the touch panel 106 using an optically clear adhesive (OCA). In one or more embodiments, the OCA is a liquid-based adhesive for bonding the cover lens film 102 to the touch panel 106. In one or more embodiments, the OCA is an optically clear tape for bonding the cover lens film 102 to the touch panel 106. The touch panel 106 includes a touch sensor IC board 114 and a touch sensor 116. In one embodiment, the touch sensor IC board 114 is a flexible and metal-based printed circuit board.

[0024] exist Figure 1A In the embodiment of the present invention, the display structure 108 is disposed between the touch panel 106 and the substrate 110. In one or more embodiments, the display structure 108 is an organic light emitting diode display. Other suitable display devices such as light emitting diode displays or liquid crystal displays utilizing the cover lens film are contemplated herein. The display structure 108 may include a thin film encapsulation, an organic light emitting layer, a driver IC board, and a thin film transistor.

[0025] exist Figure 1B In an embodiment, the film layer 104 and the touch panel 106 can be layered atop the display structure 108 such that the film layer 104 and the touch panel 106 are disposed between the display structure 108 and the cover lens film 102. In such an embodiment, the cover lens film 102 promotes abrasion resistance and impact protection.

[0026] In one or more embodiments, substrate 110 is made of a polymeric material, such as a polyimide material. The present disclosure contemplates that any flexible plastic substrate can be used for substrate 110. For example, substrate 110 may include a polyetheretherketone layer, a transparent conductive polyester layer, a polycarbonate, or any other polymer from the polyaryletherketone family. In the embodiment of FIG. 1 , substrate 110 is adjacent to shielding layer 112. In one or more embodiments, substrate 110 is polyester terephthalate. In one embodiment, shielding layer 112 is copper foil. Additional layers (such as an adhesion promoting layer) may be deposited adjacent to substrate 110 before any additional layers (such as shielding layer 112).

[0027] FIG. 2A to FIG. 2E 1 and 2 are schematic cross-sectional views of flexible cover lens films 200, 220, 230, 240, 250 according to one or more embodiments. Each of the flexible cover lens films 200, 220, 230, 240, 250 may be the cover lens film 102 of FIG. 1. The flexible cover lens films 200, 220, 230, 240, 250 may each be used in a display device, such as Figure 1A The display device 100 and / or Figure 1B Display device 150. Each of the flexible cover lens films 200, 220, 230, 240, 250 includes a substrate layer 202, one or more adhesion promoting layers 206, a first wet hard coating layer 205 deposited using a first wet deposition process, a second wet hard coating layer 204 deposited using a second wet deposition process, and a dry hard coating layer 208 deposited using a dry deposition process. The wet deposition process may include a solution including a solvent and a hard coating chemical deposited using a slot die coating head, a gravure coating head, or a rod coating head in a roll-to-roll solution processing system. In one or more embodiments, the wet deposition process includes applying (e.g., spraying or rolling, for example) a hard coating liquid (including a hard coating chemical in a solvent) onto the substrate layer 202, and the deposited solution or hard coating liquid is subsequently cured using ultraviolet radiation and / or thermal methods.

[0028] A first wet hard coating layer 205 is deposited on a first side 221 of the substrate layer 202, and a second wet hard coating layer 204 is deposited on a second side 222 of the substrate layer 202. In one or more embodiments, the first wet hard coating layer 205 is deposited on a first outer surface of the substrate layer 202 on the first side 221, and the second wet hard coating layer 204 is deposited on a second outer surface of the substrate layer 202 on the second side 222.

[0029] The dry deposition process may include chemical vapor deposition (CVD), plasma enhanced chemical vapor deposition (PECVD), atomic layer deposition (ALD), physical vapor deposition (PVD), thermal evaporation, electron beam evaporation, and / or other deposition techniques. The dry deposition process may be plasma enhanced as appropriate and may be processed in a sheet-to-sheet apparatus or a roll-to-roll apparatus. The dry deposition process may be performed in a fully equipped sheet handling apparatus, wherein a carrier glass sheet is loaded with a substrate layer 202 including a first wet hard coating layer 205 and a second wet hard coating layer 204 deposited thereon in a double-sided configuration. The substrate layer 202 may be loaded directly onto the carrier glass sheet or bonded to an elongated or ultra-thin glass substrate, which in turn may be loaded onto a carrier for the dry deposition process.

[0030] exist Figure 2A In an embodiment, one or more adhesion promoting layers 206 are deposited on the second wet hard coating layer 204. The one or more adhesion promoting layers 206 can be hard coating layers deposited using a dry deposition process. A dry hard coating layer 208 deposited using a dry deposition process is deposited on the adhesion promoting layer 206. The second wet hard coating layer 204, the adhesion promoting layer 206, and the dry hard coating layer 208 form a multi-layer hard coating layer 212. An anti-fouling layer 210 is deposited on the dry hard coating layer 208. The anti-fouling layer 210 can be an anti-fingerprint layer. The anti-fouling layer 210 can be deposited using a dry deposition process or a wet deposition process.

[0031] exist Figure 2B In an embodiment, the flexible cover lens film 220 includes an adhesion promoting layer 206 deposited on the substrate layer 202. The adhesion promoting layer 206 can be deposited using a dry vacuum deposition process, or using a wet deposition process, such as CVD, PECVD, ALD, PVD, thermal evaporation, electron beam evaporation, and / or other dry deposition processes. A dry hard coating layer 208 deposited using a dry deposition process is deposited on the adhesion promoting layer 206. A second wet hard coating layer 204 deposited using a wet deposition process is deposited on the dry hard coating layer 208. In one or more embodiments, the second wet hard coating layer 204 includes an anti-fouling or anti-fingerprint additive, and / or the anti-fouling layer is not deposited on the second wet hard coating layer 204. In one or more embodiments, the anti-fouling layer (such as Figure 2B The anti-fouling layer 210 is shown deposited on the second wet hard coating layer 204, and the anti-fouling layer can be deposited using a dry deposition process or a wet deposition process. The second wet hard coating layer 204, the adhesion promoting layer 206, and the dry hard coating layer 208 form a multi-layer hard coating layer 212.

[0032] exist Figure 2CIn an embodiment, the flexible cover lens film 230 includes an adhesion promoting layer 206 deposited on the substrate layer 202. A second wet hard coating layer 204 deposited using a wet deposition process is deposited on the adhesion promoting layer 206. A dry hard coating layer 208 deposited using a dry deposition process is deposited on the second wet hard coating layer 204. The second wet hard coating layer 204, the adhesion promoting layer 206, and the dry hard coating layer 208 form a multi-layer hard coating layer 212. An anti-fouling layer 210 is deposited on the dry hard coating layer 208. The anti-fouling layer 210 may be deposited using a dry deposition process or a wet deposition process.

[0033] exist Figure 2D In an embodiment, the flexible cover lens film 240 includes a first adhesion promoting layer 206a deposited on the substrate layer 202. The second wet hard coating layer 204 deposited using a wet deposition process is deposited on the first adhesion promoting layer 206a. The second adhesion promoting layer 206b is deposited on the second wet hard coating layer 204. The dry hard coating layer 208 deposited using a dry deposition process is deposited on the second adhesion promoting layer 206b. The first adhesion promoting layer 206a, the second wet hard coating layer 204, the second adhesion promoting layer 206b, and the dry hard coating layer 208 form a multilayer hard coating layer 212. The anti-fouling layer 210 is deposited on the dry hard coating layer 208. The anti-fouling layer 210 can be deposited using a dry deposition process or a wet deposition process.

[0034] exist Figure 2E In an embodiment, the flexible cover lens film 250 includes a first adhesion promoting layer 206a deposited on the substrate layer 202. A dry hard coating layer 208 deposited using a dry deposition process is deposited on the first adhesion promoting layer 206a. A second adhesion promoting layer 206b is deposited on the dry hard coating layer 208. A second wet hard coating layer 204 deposited using a wet deposition process is deposited on the second adhesion promoting layer 206b. In one or more embodiments, the second wet hard coating layer 204 includes an anti-fouling additive. In one or more embodiments, the anti-fouling layer is deposited on the second wet hard coating layer 204, and the anti-fouling layer can be deposited using a dry deposition process or a wet deposition process. The first adhesion promoting layer 206a, the dry hard coating layer 208, the second adhesion promoting layer 206b, and the second wet hard coating layer 204 form a multilayer hard coating layer 212.

[0035] FIG. 2A to FIG. 2EThe flexible cover lens film 200, 220, 230, 240, 250 has a pencil hardness of 3H to 9H, a total transmittance greater than 88% (such as 90% or higher), a haze of about 1% or less (such as less than 1%), and a yellowness index of b*<1. In one or more embodiments, the flexible cover lens film 200, 220, 230, 240, 250 has a pencil hardness of 9H, a total transmittance greater than 92%, and a haze of 0.5% or less. The flexible cover lens film 200, 220, 230, 240, 250 is flexible to bend to an inner radius of curvature of up to 1 mm or an outer radius of curvature of up to 2 mm in repeated cycles. The flexible cover lens film 200, 220, 230, 240, 250 has scratch resistance measured by a standard steel wool test loaded with up to 1 kg, and can withstand a large number of cycles, such as 2000 cycles. The haze change of the flexible cover lens film 200, 220, 230, 240, 250 after the steel wool abrasion test is less than 1%, thereby illustrating that the flexible cover lens film 200, 220, 230, 240, 250 can each have high abrasion resistance. The flexible cover lens film 200, 220, 230, 240, 250 has abrasion resistance as measured by the Taber abrasion resistance test with a load of up to 1 kg, and can withstand a large number of cycles, such as 100 cycles. The haze change of the flexible cover lens film 200, 220, 230, 240, 250 after the Taber abrasion resistance test is less than 2%.

[0036] exist FIG. 2A to FIG. 2E In the embodiment, the first wet hard coating layer 205 and the second wet hard coating layer 204 can each be deposited using a roll-to-roll solution processing method. The dry hard coating layer 208 can be deposited using CVD, PVD, PECVD, or ALD. In one or more embodiments, the dry hard coating layer 208 is deposited using CVD or PVD. The multilayer hard coating layer 212 can have a thickness T1 of 1 μm to 30 μm. In one or more embodiments, the thickness T1 is 5 μm to 10 μm.

[0037] exist FIG. 2A to FIG. 2EIn the embodiment of the present invention, the first wet hard coating layer 205 and / or the second wet hard coating layer 204 may include one or more of the following: polyurethane acrylate, polyester resin, polyester acrylate, epoxy acrylate, polyurethane, epoxy-polycarbonate, cellulose, acetal, polyethylene, polystyrene, polyamide, polyimide, melamine, phenol, silicone, sol-gel-siloxane hybrid, silica nanoparticles, and / or combinations thereof. Hybrid siloxanes may include organic and inorganic elements, including metal alkoxides. The second wet hard coating layer 204 deposited using a wet deposition process may further include one or more of the following: radiation curable acrylate, aliphatic polyurethane acrylate, copolymers thereof, elastomers thereof, and / or combinations thereof. The first wet hard coating layer 205 and the second wet hard coating layer 204 may each have a thickness T2 of about 0.5 μm to about 40 μm. The first wet hard coating layer 205 and the second wet hard coating layer 204 may each have a refractive index of about 1.430 to about 1.150, an optical transmittance of about 85% to about 98%, and a pencil hardness of about 2 H to about 9 H. The first wet hard coating layer 205 and the second wet hard coating layer 204 may each have a nanoindentation hardness of about 0.5 GPa to about 1.5 GPa, and / or an elastic modulus varying from about 5 GPa to about 13 GPa, as measured by nanoindentation.

[0038] The wet deposition processes for depositing the first wet hard coating layer 205 and the second wet hard coating layer 204 may each include applying a chemical solution (e.g., a hard coating liquid) using a spray nozzle and / or various Mayer rods, heating in a non-active convection oven at between 75° C. and 85° C. for between 100 seconds and 140 seconds (e.g., before, during, and / or after application), and / or at 300 mJ / cm 2 With 500mJ / cm 2 The solution of the wet deposition process can be processed in an ion atmosphere by rod coating, slot die coating, comma coating, micro gravure coating, spin coating, gravure coating, and / or cast coating. In one or more embodiments, the deposition solution of the wet deposition process is cured using ultraviolet radiation. In one or more embodiments, the deposition solution of the wet deposition process is cured using electron beam treatment. In one or more embodiments, the deposition solution of the wet deposition process is cured using a thermal process.

[0039] The dry hard coating layer 208 may include one or more of the following: silicon oxide and / or nitride, silicon oxycarbide (SiC x O y), silicon oxynitride, and / or silicon carbide (SiC). The dry hard coating layer 208 may have a thickness T3 of about 0.05 μm to about 30 μm. The precursor used in the dry deposition process may include an organic polymer precursor (liquid or gas) with carbon, such as one or more of the following: hexamethyldisiloxane (HMDSO), plasma polymerized HMDSO (ppHMDSO), tetramethylcyclotetrasiloxane (TOMCAT), hexamethyldisilazane (HMDSN), and / or tetraethylorthosilicate (TEOS). The precursor used in the dry deposition process may include sputtering various silicon dioxide and / or quartz materials to deposit various carbon mixed oxides and / or nitrides of silicon or a precursor without carbon, such as silane (SiH4).

[0040] The dry hard coating layer 208 may have a refractive index of about 1.450 to about 1.150, an optical transmittance of about 85% to about 98%, and a pencil hardness of about 2H to about 9H. The dry hard coating layer 208 may have a nanoindentation hardness of about 1 GPa to about 8 GPa, and / or an elastic modulus varying from about 5 GPa to about 70 GPa, as measured by nanoindentation. The dry hard coating layer 208 may have a high hardness controlled by a ratio of an oxidant or initiator to a precursor, such as oxygen (O2), nitrous oxide (N2O), tert-butyl peroxide (TBPO), and / or an acrylate monomer, particularly ethyl-hexyl acrylate, and / or a cross-linking agent, such as butanediol-diacrylate (BDDA), to minimize the presence of carbon in the dry hard coating layer 208.

[0041] FIG. 2A to FIG. 2E The substrate layer 202 has a thickness T4 of 2 μm to 100 μm. The substrate layer 202 is formed of one or more polymeric materials. The substrate layer 202 includes one or more of the following: polyethylene terephthalate (PET), triacetyl cellulose, polycarbonate, polyamide, polymethyl methacrylate, cycloolefin polymer, polyethylene naphthalene (PEN), and / or colorless polyimide (CPI). In one or more embodiments, the thickness T4 of the substrate layer 202 is about 25 μm to 50 μm and is a CPI layer. The anti-fouling layer 210 can be an oleophobic film. The anti-fouling layer 210 can be a perfluoropolyether (PFPE)-based silane polymer molecule (for example, including various chlorosilanes, oxysilanes, and / or fluoroethylene, etc.) covalently bonded to the surface of the layer below the anti-fouling layer 210. The anti-fouling layer 210 may be wet-coated or vacuum-dry-coated. The anti-fouling layer 210 may have a thickness of 3 nm to about 150 nm, such as about 50 nm to about 70 nm.

[0042] The one or more adhesion promoting layers 206 may have a thickness of 50 nm to 1500 nm. The one or more adhesion promoting layers 206 may be deposited using a dry deposition process and may include oxides and / or nitrides of silicon, silicon oxycarbide, and / or silicon oxynitride. Precursors used in the dry deposition process may include organic polymer precursors (liquid or gas) with carbon, such as one or more of HMDSO, ppHMDSO, TOMCAT, HMDSN, and / or TEOS. Precursors used in the dry deposition process may include sputtering various silicon dioxide and / or quartz materials to deposit various carbon mixed oxides and / or nitrides of silicon.

[0043] The one or more adhesion promoting layers 206 may be deposited in a wet deposition process and may include one or more polymeric and / or oligomeric materials such as acrylates, silicones, and / or optically clear adhesives (OCAs). In one or more embodiments, the one or more adhesion promoting layers 206 deposited using a wet deposition process may be formed of a liquid optically clear adhesive (LOCA) that may be dispensed in various ways (e.g., spray nozzles, Mayer rods, slot dies, gravure heads, and / or rod coaters, etc.) and cured by UV exposure, or heating, and / or may be moisture and / or pressure sensitive and / or cured by regulating or controlling moisture and / or pressure.

[0044] Each of the one or more adhesion promoting layers 206 may have a refractive index of about 1.430 to about 1.150, and an optical transmittance of about 85% to about 98%. Each of the one or more adhesion promoting layers 206 may have a nanoindentation hardness of about 0.4 GPa to about 5 GPa, and / or an elastic modulus varying from about 2.5 GPa to about 70 GPa, as measured by nanoindentation. Each of the one or more adhesion promoting layers 206 may have a relatively high hardness controlled by the ratio of an oxidant or initiator to a precursor, such as O2, N2O, TBPO, and / or an acrylate monomer, such as ethyl-hexyl acrylate, and / or a crosslinker, such as BDDA, to accurately control the presence of carbon.

[0045] One or more of the flexible cover lens films 200, 220, 230, 240, 250 may be stacked on each other. For example, the flexible cover lens film 200 may be stacked on the flexible cover lens film 220, or there may be two flexible cover lens films 200, so that there are two flexible cover lens films 200. The multi-layer hard coating layer 212 may be stacked one or more times on the substrate layer 202. The first wet hard coating layer 205 may be stacked one or more times under the substrate layer 202. One or more flexible cover lens films 200, 220, 230, 240, 250, the stacked first wet hard coating layer 205, and / or the stacked multi-layer hard coating layer 212 may be independently attached, bonded, or otherwise held together by one or more adhesives, such as using one or more OCAs. One or more flexible cover lens films 200, 220, 230, 240, 250, the stacked first wet hard coating layer 205, and / or the stacked multi-layer hard coating layer 212 may be independently adhered, bonded, or otherwise held together without the use of an adhesive.

[0046] Figure 3 is a schematic cross-sectional view of an exemplary embodiment of a flexible cover lens film 300 according to one or more embodiments, the flexible cover lens film including a double-stacked multi-layer hard coating layer of the flexible cover lens film 200 and a double-stacked first wet hard coating layer 205. In the flexible cover lens film 300, the first multi-layer hard coating layer 212a is disposed on the second side of the substrate layer 202, and the second multi-layer hard coating layer 212b is disposed on the first multi-layer hard coating layer 212a. Two first wet hard coating layers 205a, 205b are disposed on the first side of the substrate layer 202. One or more adhesion layers 306 are disposed between the first multi-layer hard coating layer 212a and the second multi-layer hard coating layer 212b. One or more adhesion layers 306 may be sacrificial adhesion layers. One or more adhesion layers 306 may be FIG. 2A to FIG. 2E The first and second multi-layer hard coating layers 212a, 212b both include a second wet hard coating layer 204, an adhesion promoting layer 206 disposed on the second wet hard coating layer 204, and a dry hard coating layer 208 disposed on the adhesion promoting layer 206. Figure 3 212b. The present disclosure contemplates that the anti-fouling layer 210 may be omitted.

[0047] If it is desired to remove and replace the topmost flexible cover lens film (e.g., due to scratching or other damage), such as Figure 3 The second multi-layer hard coating 212b may selectively degrade, destroy, or otherwise remove one or more adhesive layers (such as adhesive layer 306) to facilitate attaching a top cover lens (e.g., Figure 3 The second multi-layer hard coating 212b) and the bottom cover lens film (eg, Figure 3The first multi-layer hard coating 212a is separated. The two stacked adhesives (e.g., Figure 3 The adhesive layer 306) may degrade under ultraviolet (UV) light of a predetermined temperature, a predetermined wavelength and / or a dose, and / or by a predetermined mechanical removal mechanism.

[0048] In one or more embodiments, two stacked flexible cover lens films (e.g., Figure 3 The first and second multi-layer hard coatings 212a, 212b) of the sacrificial adhesive (eg, Figure 3 The adhesive layer 306 of the sacrificial adhesive may be degradable at a predetermined temperature. For example, the adhesive may be degradable at a temperature of about 80°C, about 90°C, or about 100°C to about 120°C. In one or more embodiments, the sacrificial adhesive is degradable when exposed to UV light at a predetermined wavelength and / or a predetermined dose. For example, the adhesive is degradable when exposed to UV light having a wavelength of about 350nm to about 375nm (such as about 365nm). The adhesive may be degraded by exposing the adhesive to UV light for a period of about 0.5 seconds, about 1 second, or about 5 seconds to about 30 seconds, about 60 seconds, or about 90 seconds.

[0049] The method of forming the flexible cover lens film 200, 220, 230, 240, 250 may include positioning a substrate layer 202 and depositing a multilayer hard coating layer 212 on the substrate layer 202. The layers 204-208 of the multilayer hard coating layer 212 may be deposited using both wet and dry deposition processes, such as CVD, PVD, ambient (e.g., atmospheric) solution processing methods, in a sheet-to-sheet processing apparatus, and / or a roll-to-roll apparatus. It is contemplated that additional layers may be present in the flexible cover lens film 200, 220, 230, 240, 250, such as additional adhesion promoting layers or impact resistant layers. The cover lens films described herein may be used in any display apparatus.

[0050] Combining wet and dry deposition processes to form a multi-layer hard coating promotes an optically transparent, high hardness, and bendable cover lens film. Combining dry and wet films promotes enhanced anti-abrasion properties and elasticity of the cover lens film while allowing an anti-fouling layer to be deposited on top of the multi-layer hard coating. By combining wet and dry deposition processes to form a multi-layer hard coating, the cover lens film has enhanced elasticity, strength, optical transmittance, wear resistance, anti-abrasion properties, and thermal stability.

[0051] Figure 4A is a schematic plan view of a coating system 400 during a first wet deposition process according to one or more embodiments.

[0052] The coating system 400 includes a first rotatable rod 402 configured to receive a first storage roll 404, a second rotatable rod 406 configured to receive a second storage roll 408, and a plurality of transfer rollers 410. The transfer rollers 410 are disposed along a transfer path between the first storage roll 404 and the second storage roll 408. The coating system 400 includes a coating module 414 interfaced with a first section 412a of the transfer path, and the coating module 414 includes a rod, a slot die, one or more comma rollers, a micro-gravure, a gravure, one or more casting nozzles, one or more casting rollers, and / or a plurality of spray nozzles 415. The present disclosure contemplates that one or more spray nozzles 415 may be used. The coating system 400 includes a curing module 416 interfaced with a second section 412b of the transfer path. The curing module 416 includes one or more ultraviolet (UV) light sources 417. The present disclosure contemplates that other energy sources (such as microwave sources, heat sources, and / or electron beam sources) may be used in place of the UV light sources 417.

[0053] The first storage roll 404 is mounted to the first rotatable rod 402, and the second storage roll 408 is mounted to the second rotatable rod 406. The substrate layer 202 is wound on the first storage roll 404. During the first wet deposition process, the first rotatable rod 402 is driven to rotate the first storage roll 404 in the first rotation direction RD1, and the second rotatable rod 406 is driven to rotate the second storage roll 408 in the second rotation direction RD2. The substrate layer 202 is transferred from the first storage roll 404 and transferred to the second storage roll 408. During the transfer, the coating module 414 coats (e.g., sprays or rolls, for example) the liquid hard coating layer onto the first side 221 of the substrate layer 202 to form the first wet hard coating layer 205. The second side 222 rolls over the transfer roller 410 during the transfer. During the transfer, the UV light source 417 directs energy (eg, UV light) toward the first wet hard coating layer 205 to cure the first wet hard coating layer 205 .

[0054] The first storage roll 404 is rotated in the first rotation direction RD1, and the second storage roll 408 is rotated in the second rotation direction RD2 opposite to the first rotation direction RD1 to wind the substrate layer 202 and the first wet hard coating layer 205 onto the second storage roll 408 so that the first side 221 and the second side 222 are turned over (see Figure 4B ).

[0055] Figure 4B is a schematic plan view of a coating system 400 during a second wet deposition process according to one or more embodiments.

[0056] exist Figure 4A The first wet deposition process with Figure 4BIn one or more embodiments, the positions of the first storage roll 404 and the second storage roll 408 are changed between the first and second wet deposition processes. In one or more embodiments, the second storage roll 408 is positioned (e.g., mounted to the first rotatable rod 402) in place of the first storage roll 404 for the second wet deposition process. In one or more embodiments, the third storage roll 418 is mounted to the second rotatable rod 406. In one or more embodiments, the positions of the first storage roll 404 and the second storage roll 408 are swapped such that the second storage roll 408 is mounted to the first rotatable rod 402 and the first storage roll 404 is mounted to the second rotatable rod 406.

[0057] The first side 221 and the second side 222 are flipped so that the second side 222 faces the coating module 414, and the first side 221 and the first wet hard coating layer 205 face the transfer roller 410. During the second wet deposition process, the second storage drum 408 rotates in the first rotation direction RD1, and the third storage drum 418 rotates in the second rotation direction RD2.

[0058] The substrate layer 202 and the first wet hard coating layer 205 are transferred from the second storage roll 408 and transferred to the third storage roll 418. During the transfer, the coating module 414 applies (e.g., sprays or rolls, for example) the liquid hard coating layer onto the second side 222 of the substrate layer 202 to form the second wet hard coating layer 204. The first wet hard coating layer 205 rolls over the transfer roller 410 during the transfer. During the transfer, the UV light source 417 directs energy (e.g., UV light) toward the second wet hard coating layer 204 to cure the second wet hard coating layer 204. Simultaneously with the rotation of the third storage roll 418, the third rotatable rod 421 is driven to rotate the fourth storage roll 422 (in the second rotation direction RD2) to transfer the protective film 423 from the fourth storage roll 422 and transfer it to the third storage roll 418. The protective film 423 wound onto the third storage roll 418 is deposited on the cured second wet hard coating layer 204. The protective film 423 is deposited between the second wet hard coating layer 204 and the first wet hard coating layer 205.

[0059] The present disclosure contemplates that other deposition equipment may be used in place of coating module 414. In one or more embodiments, a first hard coating roller may roll the liquid adhesive on first side 221 to form first wet hard coating layer 205, and a second hard coating roller may simultaneously roll the liquid adhesive on second side 222 to form second wet hard coating layer 204.

[0060] Figure 5 is a schematic block diagram illustration of a method 500 of forming a cover lens structure according to one or more embodiments.

[0061] Operation 502 includes depositing a first hard coating layer on a first side of a substrate layer using a first wet deposition process. The substrate layer is a polymeric layer. In one or more embodiments, the substrate layer is formed of one or more of the following: polyethylene terephthalate (PET), polyethylene naphthalate (PEN), cellulose triacetate (TAC), polyimide (PI), and / or colorless polyimide (CPI). The present disclosure contemplates that other polymeric materials may be used for the substrate layer. In one or more embodiments, depositing the first hard coating layer includes applying a hard coating liquid on the first side, and curing the hard coating liquid on the first side. In one or more embodiments, depositing the first hard coating layer includes rotating a first storage roll in a first rotational direction, and rotating a second storage roll in a second rotational direction opposite to the first rotational direction to transfer the substrate layer from the first storage roll to the second storage roll. In one or more embodiments, transferring the substrate layer from the first storage roll to the second storage roll includes moving the substrate layer over a plurality of transfer rollers disposed along a transfer path between the first storage roll and the second storage roll.

[0062] Operation 503 includes changing the position of the first storage reel and the second storage reel. In one or more embodiments, the change includes exchanging the position of the first storage reel and the second storage reel. In one or more embodiments, the change includes replacing the first storage reel to position the second storage reel, and replacing the second storage reel to position the third storage reel.

[0063] Operation 504 includes depositing a second hard coating layer on a second side of the substrate layer using a second wet deposition process. In one or more embodiments, depositing the second hard coating layer includes applying a hard coating liquid on the second side, and curing the hard coating liquid on the second side. In one or more embodiments, depositing the second hard coating layer includes rotating the second storage roll in a first rotational direction, and rotating the third storage roll in a second rotational direction opposite to the first rotational direction to transfer the substrate layer from the second storage roll to the third storage roll. In one or more embodiments, method 500 includes, while rotating the third storage roll, rotating the fourth storage roll in the second rotational direction to transfer the barrier film from the fourth storage roll to the third storage roll, and depositing the barrier film between the first hard coating layer and the second hard coating layer.

[0064] The first wet deposition process of operation 502 and the second wet deposition process of operation 504 each use a roll-to-roll apparatus such as Figure 4A and Figure 4B A transfer roll 410 and storage rolls 404, 408, 418, 422 are shown depositing the first and second hard coating layers.

[0065] Operation 506 includes depositing one or more adhesion promoting layers. In one or more embodiments, one or more adhesion promoting layers are deposited on the second hard coating layer.

[0066] Operation 508 includes depositing a third hard coating layer using a dry deposition process. In one or more embodiments, the third hard coating layer is deposited on the one or more adhesion promoting layers.

[0067] Operation 510 includes depositing an anti-soiling layer. In one or more embodiments, the anti-soiling layer is deposited on the third hard coating layer.

[0068] The first hard coating layer and the second hard coating layer are each deposited at a rolling temperature of less than 58 degrees C. In one or more embodiments, the rolling temperature is ambient temperature, for example, room temperature.

[0069] Operation 512 includes providing a cover lens structure to position a first hard coating layer over a touch panel and a display structure of a display device.

[0070] Benefits of the present disclosure include strong mechanical properties (such as hardness and impact resistance), abrasion resistance, flexibility, elasticity, optical transmittance, and / or wear resistance. Benefits of the present disclosure also include low haze, low oligomer migration (such as within and from substrate layer 202), and / or low yellowness index. As an example, the present disclosure promotes lower oligomer migration in and from the substrate layer, lower haze, lower yellowness index, and enhanced optical transmittance (and optical device performance) at relatively strong mechanical properties.

[0071] It is contemplated that aspects described herein may be combined. For example, the flexible cover lens films 200, 220, 230, 240, 250, and / or 300, the display device 100, the coating system 400, Figure 4A The first wet deposition process shown, Figure 4B One or more features, aspects, components, operations, and / or properties of the illustrated second wet deposition process, and / or method 500. It is further contemplated that combinations may achieve the aforementioned benefits.

[0072] Although the foregoing relates to embodiments of the present disclosure, other and further embodiments of the present disclosure may be devised without departing from its basic scope. The present disclosure also contemplates that one or more aspects of the embodiments described herein may be substituted for one or more of the other aspects described. The scope of the present disclosure is determined by the appended claims.

[0073] Certain embodiments and features have been described using a set of numerical upper limits and a set of numerical lower limits. It should be understood that, unless otherwise indicated, ranges that include combinations of any two values ​​are contemplated, e.g., any lower value combined with any higher value, any two lower values ​​combined, and / or any two higher values ​​combined. Certain lower limits, upper limits, and ranges may appear in one or more claims below.

Claims

1. A cover lens structure for a display device, comprising: A substrate layer comprising a first side and a second side; a first wet hard coating layer deposited on the first side of the substrate layer; a second wet hard coating layer deposited on the second side of the substrate layer; one or more adhesion promoting layers formed on the second side of the substrate layer; as well as A dry hard coating layer is formed on the second side of the substrate layer.

2. The cover lens structure of claim 1, further comprising: An antifouling layer is formed on the dry hard coating layer, wherein the one or more adhesion promoting layers are formed on the first wet hard coating layer, and the dry hard coating layer is formed on the one or more adhesion promoting layers.

3. The cover lens structure of claim 1, wherein the substrate layer is formed from one or more polymeric materials.

4. The cover lens structure of claim 3, wherein the substrate layer is formed of polyethylene terephthalate (PET).

5. The cover lens structure of claim 3, wherein the first wet hard coating layer and the second wet hard coating layer each comprise one or more of the following: one or more polyurethane acrylates, polyester resins, polyester acrylates, epoxy acrylates, polyurethanes, epoxy-polycarbonates, cellulose, acetals, polyethylene, polystyrene, polyamides, polyimides, melamine, phenols, silicones, one or more sol-gel-siloxane hybrids, or silica nanoparticles.

6. The cover lens structure of claim 3, wherein the dry hard coating layer comprises one or more of the following: one or more silicon oxides, one or more silicon nitrides, one or more silicon oxycarbides, one or more silicon oxynitrides, or one or more silicon carbides.

7. A method for forming a cover lens structure, comprising the following steps: depositing a first hard coating layer on a first side of the substrate layer using a first wet deposition process; depositing a second hard coating layer on a second side of the substrate layer using a second wet deposition process; depositing one or more adhesion promoting layers over the second side; depositing a third hard coating layer over the second side using a dry deposition process; depositing an antifouling layer over the second side; as well as The cover lens structure is disposed to position the first hard coating layer over the touch panel and display structure of the display device.

8. The method of claim 7, wherein the first hard coating layer and the second hard coating layer are each deposited at a rolling temperature of less than 58 degrees Celsius, the one or more adhesion promoting layers are deposited on the second hard coating layer, the third hard coating layer is deposited on the one or more adhesion promoting layers, and the anti-fouling layer is deposited on the third hard coating layer.

9. The method of claim 7, wherein the substrate layer is formed of one or more polymeric materials.

10. The method of claim 9, wherein the substrate layer is formed of polyethylene terephthalate (PET).

11. The method of claim 7, wherein the step of depositing the first hard coating layer and the step of depositing the second hard coating layer each comprise the following steps: spraying a hard coating liquid on the first side or the second side respectively; and The hard coating liquid is cured on the respective first side or the second side.

12. The method of claim 11, wherein the step of depositing the first hard coating layer further comprises the steps of: rotating the first storage reel in a first rotational direction; and The second storage reel is rotated in a second rotational direction opposite to the first rotational direction to transfer the substrate layer from the first storage reel to the second storage reel.

13. The method of claim 12, wherein the step of transferring the substrate layer from the first storage roll to the second storage roll comprises the following steps: The substrate layer is moved over a plurality of transfer rollers disposed along a transfer path between the first storage roll and the second storage roll.

14. The method of claim 12, further comprising the step of changing the positions of the first storage reel and the second storage reel.

15. The method of claim 14, wherein the step of depositing the second hard coating layer further comprises the steps of: rotating the second storage reel in the first rotational direction; and The third storage reel is rotated in the second rotational direction to transfer the substrate layer from the second storage reel to the third storage reel.

16. The method of claim 15, further comprising the steps of: The fourth storage reel is rotated in the second rotational direction to transfer a barrier film from the fourth storage reel to the third storage reel and deposit the barrier film between the first hard coating layer and the second hard coating layer.

17. A coating system comprising: a first rotatable rod configured to receive a first storage roll; a second rotatable rod configured to receive a second storage roll; a plurality of transfer rollers disposed along a transfer path between the first storage reel and the second storage reel; a coating module interfaced with the first section of the transfer path, the coating module comprising one or more of: a rod, a slot die, one or more comma rollers, a micro-gravure, a gravure, one or more casting nozzles, one or more casting rollers, or one or more spray nozzles; as well as A curing module is connected to the second section interface of the transfer path.

18. The coating system of claim 17, wherein the curing module comprises one or more ultraviolet (UV) light sources.

19. The coating system of claim 17, wherein the first storage roll is mounted to the first rotatable rod, the second storage roll is mounted to the second rotatable rod, and the substrate layer is wound onto the first storage roll.

20. The coating system of claim 19, wherein the substrate layer is formed from one or more polymeric materials.

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