Cover plate, display module and display device

Abstract

A cover plate comprises a cover plate body, the cover plate body comprises a bending area (10) and a non-bending area (20) located on both sides of the bending area (10), the non-bending area (20) comprises a glass substrate (1), and the bending area (10) comprises a first optical resin coating (2) formed by a coating process with an optical resin material. A display module and a display device. The cover plate body at least comprises two structures of the first optical resin coating (2) and the glass substrate (1), the first optical resin coating (2) with strong bending performance is arranged in the bending area (10), and the glass substrate (1) with strong impact resistance is arranged in the non-bending area (20), so that the problem that the bending performance and the impact resistance cannot be considered simultaneously when only the glass substrate (1) is used for the cover plate is solved.

Description

Technical Field

[0001] This disclosure relates to the field of display product manufacturing technology, and in particular to a cover plate, a display module, and a display device. Background Technology

[0002] When the glass thickness reaches below 100µm, its flexibility becomes apparent. Currently, ultra-thin flexible glass has become a core component of foldable display cover panels. Compared to polymer materials, glass has a higher Young's modulus and exhibits better deformation recovery after bending. When applied to foldable screens, it can significantly improve the crease problem. However, to ensure good bending performance of foldable displays, the glass thickness must be very thin. Currently, the thickness of commonly used ultra-thin glass is generally between 30 and 70µm. However, when the glass thickness reaches 70µm or less, its impact resistance is extremely weak; that is, impact resistance and bending performance cannot be simultaneously achieved.

[0003] Compared to conventional rigid mobile phone cover glass, ultra-thin flexible glass is much more expensive, sometimes by tens of times. How to use thicker glass to replace or partially replace ultra-thin flexible glass has become a hot research topic. Summary of the Invention

[0004] To address the aforementioned technical problems, this disclosure provides a cover plate, a display module, and a display device, resolving the issue that the cover plate, made of glass, cannot simultaneously achieve both impact resistance and bending performance.

[0005] To achieve the above objectives, the technical solution adopted in this disclosure is: a cover plate, including a cover plate body, the cover plate body including a bending area and non-bending areas located on both sides of the bending area, the non-bending areas including a glass substrate, and the bending area including a first optical resin coating formed by coating process using optical resin material.

[0006] Optionally, the cover plate body includes a first side and a second side disposed opposite to each other along its thickness direction, and the bending area includes the glass substrate and a second optical resin coating applied to the glass substrate in the direction from the first side to the second side;

[0007] The first optical resin coating has a first surface located on the second side, and the second optical resin coating has a second surface located on the second side, with the first surface and the second surface located on the same plane.

[0008] Optionally, the glass substrate has a third surface located on the first side, and the first optical resin coating includes a fourth surface located on the first side, wherein the third surface and the fourth surface are located in the same plane.

[0009] Optionally, a first flexible film is bonded to the first side of the cover plate body via an optical adhesive layer, or a first flexible film is bonded to the second side of the cover plate body via an optical adhesive layer.

[0010] Optionally, the first flexible membrane material is made of PET, CPI, PMMA or ultra-thin glass.

[0011] Optionally, the thickness of the first flexible membrane material is less than or equal to 20 μm.

[0012] Optionally, the cover plate body further includes a transition area located between the bending area and the non-bending area, the transition area including a third optical resin coating, the third optical resin coating including a fifth surface located on the second side, the fifth surface being located on the same plane as the second surface;

[0013] The glass substrate has a third surface located on the first side, and the third optical resin coating includes a sixth surface located on the first side, the sixth surface being in the same plane as the third surface.

[0014] Optionally, in the direction from the first side to the second side, the bending region includes a second flexible film and the first optical resin coating applied to the second flexible film.

[0015] Optionally, the second flexible membrane material is made of PET, CPI, PMMA or ultra-thin glass.

[0016] Optionally, the thickness of the second flexible membrane material is less than or equal to 70 μm.

[0017] Optionally, a third flexible film material is bonded to the first side of the cover plate body via an optical adhesive layer; or a third flexible film material is bonded to the second side of the cover plate body via an optical adhesive layer.

[0018] Optionally, the third flexible membrane material is made of PET, CPI, PMMA or ultra-thin glass.

[0019] Optionally, the thickness of the glass substrate is greater than or equal to 300 μm.

[0020] Optionally, the glass substrate includes a side surface disposed near the bending area and a light-incident surface and a light-exit surface adjacent to the side surface, wherein the light-incident surface is used to receive light emitted by the display panel;

[0021] The edge where the light-emitting surface intersects with the side surface is chamfered or rounded, and / or the edge where the light-incident surface intersects with the side surface is chamfered or rounded.

[0022] Optionally, the cross-section of the glass substrate near the bending area in the thickness direction of the cover plate body is a 1 / 2 ellipse, or the cross-section of the glass substrate near the bending area in the thickness direction of the cover plate body is a 1 / 4 ellipse, and the 1 / 4 ellipse protrudes in a direction away from the light-incident surface.

[0023] Optionally, in the direction from the non-bending area to the bending area, the light-emitting surface of the glass substrate includes a planar portion, a beveled portion, and an arc-shaped portion, wherein the arc-shaped portion is formed by rounding the corners at the intersection of the light-emitting surface and the side surface; and / or, in the direction from the non-bending area to the bending area, the light-incident surface of the glass substrate includes a planar portion, a beveled portion, and an arc-shaped portion, wherein the arc-shaped portion is formed by rounding the corners at the intersection of the light-incident surface and the side surface.

[0024] Optionally, the first optical resin coating, the second optical resin coating, and the third optical resin coating are made of the same material, and the difference between the refractive index of the first optical resin coating and the refractive index of the glass substrate is less than or equal to 0.01.

[0025] Optionally, the refractive index of the first optical resin coating is n, where 1.50 ≤ n ≤ 1.54.

[0026] Optionally, the transmittance of the first optical resin coating is greater than or equal to 90%.

[0027] Optionally, the material of the first optical resin coating is one or more of the following: polyester, polyurethane, thermoplastic polyurethane, polyamide, polyimide, polymethyl methacrylate, polypropylene, polyethylene, polypropylene, polyvinyl chloride, polystyrene, styrene, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polysulfone, polyaryletherketone, styrene, polyolefin, and polyolefin.

[0028] This disclosure also provides a display module, including a display panel and the aforementioned cover plate located on the light-emitting side of the display panel.

[0029] Optionally, the display panel includes a bonding area, which is bent to the backlight side of the display panel to bond with the main circuit board, and a protective adhesive layer is provided on the side of the bonding area near the cover plate;

[0030] The orthographic projection of the binding area on the cover plate completely coincides with the cover plate, or the orthographic projection of the binding area on the cover plate is located in a first region of the cover plate, the cover plate including an edge region exposed outside the first region.

[0031] Optionally, the cover plate includes an edge region exposed outside the first region, and the middle frame of the display module is connected to the side of the edge region near the display panel.

[0032] This disclosure also provides a display device, including the display module described above.

[0033] The beneficial effects of this disclosure are: the cover plate body includes at least two structures, namely a first optical resin coating and a glass substrate. The first optical resin coating with strong bending performance is provided in the bending area, and the glass substrate with strong impact resistance is provided in the non-bending area, thus solving the problem that the cover plate cannot simultaneously achieve both bending performance and impact resistance when using only a glass substrate. Attached Figure Description

[0034] Figure 1 This diagram illustrates the folding state of the cover plate in this embodiment of the present disclosure. Figure 1 ;

[0035] Figure 2 This diagram illustrates the flattened state of the cover plate in this embodiment of the present disclosure. Figure 1 ;

[0036] Figure 3 This diagram illustrates the flattened state of the cover plate in this embodiment of the present disclosure. Figure 2 ;

[0037] Figure 4 This diagram illustrates the flattened state of the cover plate in this embodiment of the present disclosure. Figure 3 ;

[0038] Figure 5 This diagram illustrates the folding state of the cover plate in this embodiment of the present disclosure. Figure 2 ;

[0039] Figure 6 This diagram illustrates the flattened state of the cover plate in this embodiment of the present disclosure. Figure 4 ;

[0040] Figure 7 This diagram illustrates the flattened state of the cover plate in this embodiment of the present disclosure. Figure 5 ;

[0041] Figure 8 This diagram illustrates the structure of the display module in the embodiments of this disclosure. Figure 1 ;

[0042] Figure 9 This diagram illustrates the structure of the display module in the embodiments of this disclosure. Figure 2 ;

[0043] Figure 10 This diagram illustrates the structure of the display module in the embodiments of this disclosure. Figure 3 ;

[0044] Figure 11 Schematic diagram of the structure of the glass substrate in the embodiments of this disclosure. Figure 1 ;

[0045] Figure 12 Schematic diagram of the structure of the glass substrate in the embodiments of this disclosure. Figure 2 ;

[0046] Figure 13 Schematic diagram of the structure of the glass substrate in the embodiments of this disclosure. Figure 3 ;

[0047] Figure 14 Schematic diagram of the structure of the glass substrate in the embodiments of this disclosure. Figure 4 ;

[0048] Figure 15 Schematic diagram of the structure of the glass substrate in the embodiments of this disclosure. Figure 5 ;

[0049] Figure 16 This diagram illustrates the assembly state of the cover plate and the middle frame in an embodiment of this disclosure. Figure 1 ;

[0050] Figure 17 This diagram illustrates the assembly state of the cover plate and the middle frame in an embodiment of this disclosure. Figure 2 ;

[0051] Figure 18 This is a schematic diagram showing the state of the cover plate being bent into a teardrop shape in an embodiment of this disclosure. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this disclosure. All other embodiments obtained by those skilled in the art based on the described embodiments of this disclosure are within the scope of protection of this disclosure.

[0053] In the description of this disclosure, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0054] refer to Figures 1-15 This embodiment provides a cover plate, including a cover plate body. The cover plate body includes a bending region 10 and non-bending regions 20 located on both sides of the bending region 10. The non-bending regions 20 include a glass substrate 1. The bending region 10 includes a first optical resin coating 2 formed by coating an optical resin material.

[0055] In related technologies, to ensure good bending performance of foldable displays, the glass thickness must be very thin. The thickness of ultra-thin glass commonly used in these technologies is generally between 30 and 70 μm. However, when the glass thickness reaches 70 μm or less, the impact resistance of the glass is extremely weak, meaning that both impact resistance and bending performance cannot be achieved simultaneously. In this embodiment, the cover plate body combines the first resin coating and the glass substrate 1. The first optical resin coating 2 with strong bending performance is provided in the bending area 10, and the glass substrate 1 with strong impact resistance is provided in the non-bending area 20. Since the glass substrate 1 is only provided in the non-bending area 20, and the non-bending area does not need to be bent, the thickness of the glass substrate 1 can be set according to the impact resistance requirements. It is not necessary to use ultra-thin glass. For example, the thickness of the glass substrate 1 can be greater than or equal to 300um. That is to say, by combining the two structures of providing the first optical resin coating 2 in the bending area 20 and providing the glass substrate 1 in the non-bending area 10, both good bending performance and good impact resistance of the cover plate can be guaranteed.

[0056] refer to Figure 1 and Figure 2 , Figure 1 A schematic diagram showing the folded state of the cover plate. Figure 2 A schematic diagram showing the unfolded state of the cover plate. Figure 1 When the cover plate is folded, it has a U-shaped structure. The EF and F'E' segments are non-bending areas 20, and the FP-PF' segment is a bending area 10. Since the EF and F'E' segments do not require bending, the glass substrate 1 can be used (the glass substrate 1 here can be conventional glass, and ultra-thin glass is not required), which can greatly improve the impact strength of the non-bending area 20. The FP-PF' segment can be filled by the first optical resin coating 2 formed by coating and curing optical resin to ensure bending performance.

[0057] For example, in order to ensure the impact resistance of the cover plate, the thickness of the glass substrate 1 is greater than or equal to 300 μm, but is not limited thereto.

[0058] The first optical resin coating 2 is formed by coating and curing, and has strong bending performance. The material of the first optical resin coating 2 can be one or more of the following: polyester, polyurethane, thermoplastic polyurethane, polyamide, polyimide, polymethyl methacrylate, polypropylene, polyethylene, polypropylene, polyvinyl chloride, polystyrene, styrene, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polysulfone, polyaryletherketone, styrene, polyolefin, and polyolefin.

[0059] For example, the bending area 10 can be completely filled with the first optical resin coating 2, as shown in the reference. Figure 2 However, this is not the limitation. For example, in some embodiments, in order to enhance the impact resistance of the bending area 10, a flexible film material (embedded in the first optical resin coating 2) may be added to the bending area 10. However, the thickness of the flexible film material should be small to ensure the bending performance of the bending area 10. For example, it can be less than 70 μm, but this is not the limitation.

[0060] For example, the cover plate body includes a first side and a second side disposed opposite to each other along its thickness direction, and the bending area 10 includes the glass substrate 1 and a second optical resin coating 3 coated on the glass substrate 1.

[0061] The first optical resin coating 2 has a first surface located on the second side, and the second optical resin coating 3 has a second surface located on the second side. The first surface and the second surface are located on the same plane. (Refer to...) Figures 2-4 .

[0062] The second optical resin coating 3 is provided to compensate for the step difference between the glass substrate 1 and the first optical resin coating 2, and to ensure the flatness of the second side of the cover plate body.

[0063] For example, the first optical resin coating 2 and the second optical resin coating 3 are an integral structure, and the first optical resin coating 2 and the second optical resin coating 3 are formed by a synchronous process.

[0064] For example, in order to ensure that there are no interface marks at the junction of the glass substrate 1 and the first optical resin coating 2 or the second optical resin coating 3, the first optical resin coating 2 and the second optical resin coating 3 are made of the same material, and the difference in refractive index between the first optical resin coating 2 and the glass substrate 1 is less than or equal to 0.01. For example, the refractive index of the first optical resin coating 2 is n, 1.50≤n≤1.54, but it is not limited thereto.

[0065] For example, the glass substrate 1 has a third surface located on the first side, and the first optical resin coating 2 includes a fourth surface located on the first side, the third surface and the fourth surface being located in the same plane.

[0066] For example, a first flexible film 4 is bonded to the first side of the cover plate body via an optical adhesive layer, and / or a first flexible film 4 is bonded to the second side of the cover plate body via an optical adhesive layer, for reference. Figure 3 and Figure 4 .

[0067] For example, the first flexible membrane material 4 can be made of organic materials such as PET (polyethylene terephthalate), CPI (polyimide), and PMMA (polymethyl methacrylate), or made of ultra-thin glass. It can combine impact resistance, scratch resistance, bending resistance, and surface hardness.

[0068] For example, the thickness of the first flexible membrane 4 is 50-80 μm.

[0069] Figure 3 The image shows an example of the first flexible membrane material being disposed on the first side. Figure 4 The diagram illustrates an example of the first flexible film material being disposed on the second side. It should be noted that if the first flexible film material is disposed on the side of the cover plate body used to connect with the display panel, then the first flexible film material can protect the display panel and enhance its overall impact resistance. If the first flexible film material is disposed on the side of the cover plate body opposite to the side connected to the display panel, that is, on the side of the cover plate body away from the display panel, then the first flexible film material protects both the cover plate body and the display panel, improving the impact resistance of the display module. Furthermore, the first flexible film material can serve as a human-machine interface surface, enhancing its abrasion resistance.

[0070] It should be noted that, since ultra-thin glass is fragile, in some embodiments, when the first flexible film is disposed on the side of the cover plate body away from the display panel, the first flexible film is made of organic materials such as PET (polyethylene terephthalate), CPI (polyimide), and PMMA (polymethyl methacrylate).

[0071] refer to Figures 5-10 For example, the cover plate body also includes a transition region 30 located between the bending region 10 and the non-bending region 20, the transition region 30 including a third optical resin coating 6, the third optical resin coating 6 including a fifth surface located on the second side, the fifth surface being located on the same plane as the second surface;

[0072] The glass substrate 1 has a third surface located on the first side, and the third optical resin coating 6 includes a sixth surface located on the first side, the sixth surface and the third surface being located in the same plane.

[0073] For the cover plate that is teardrop-shaped when folded, the transition zone 30 experiences the greatest tensile stress and is prone to cracking during bending. In this embodiment, the third optical resin coating 6 is provided in the transition zone 30 and the transition zone 30 is completely filled by the third optical resin coating 6 to ensure the bending performance of the transition zone 30 and avoid cracking during bending.

[0074] For example, in the direction from the first side to the second side, the bending region 10 includes a second flexible film 7 and the first optical resin coating 2 coated on the second flexible film 7.

[0075] The bending area 10 is subjected to the greatest compressive stress. By combining the first optical resin coating 2 and the second flexible film material 7, the compressive strength of the bending area 10 can be increased, and its bending performance can be guaranteed.

[0076] For example, the second flexible membrane material 7 can be made of organic materials such as PET (polyethylene terephthalate), CPI (polyimide), and PMMA (polymethyl methacrylate), or made of ultra-thin glass. It can combine impact resistance, scratch resistance, bending resistance, and surface hardness.

[0077] The first side or the second side of the cover plate body is used to connect with the display panel. It should be noted that when the first side of the cover plate body is used to connect with the display panel, since ultra-thin glass is fragile, in some embodiments, the second flexible film material is made of organic materials such as PET (polyethylene terephthalate), CPI (polyimide), and PMMA (polymethyl methacrylate).

[0078] For example, the first side of the cover plate body is bonded with a third flexible film 8 by an optical adhesive layer; and / or the second side of the cover plate body is bonded with a third flexible film 8 by an optical adhesive layer.

[0079] For example, the third flexible membrane material 8 can be made of organic materials such as PET (polyethylene terephthalate), CPI (polyimide), and PMMA (polymethyl methacrylate), or made of ultra-thin glass. It can combine impact resistance, scratch resistance, bending resistance, and surface hardness.

[0080] For example, the thickness of the third flexible membrane material 8 is 50-80 μm.

[0081] It should be noted that the third flexible film material is disposed on the side of the cover plate body used to connect with the display panel. Therefore, the third flexible film material 8 can protect the display panel and enhance the overall impact resistance of the display panel. The third flexible film material 8 is disposed on the side of the cover plate body opposite to the side connected with the display panel, that is, on the side of the cover plate body away from the display panel. Therefore, the third flexible film material 8 protects both the cover plate body and the display panel, improves the impact resistance of the display module, and can also serve as a human-machine interaction surface to enhance its friction resistance.

[0082] It should be noted that, since ultra-thin glass is fragile, in some embodiments, when the third flexible film material 8 is disposed on the side of the cover plate body away from the display panel, the material of the third flexible film material 8 is made of organic materials such as PET (polyethylene terephthalate), CPI (polyimide), and PMMA (polymethyl methacrylate).

[0083] In some embodiments, the first side of the cover plate body is used to connect with the display panel, and the second side is provided with the third flexible film material 8. Due to the provision of the third flexible film material 8, the second flexible film material 7 can be made of ultra-thin glass, and the third flexible film material 8 plays a protective role.

[0084] refer to Figures 7-9 , Figure 7 and Figure 8 The diagram shows that the first side of the cover plate body is used for connection with the display panel, and the second side is bonded with a third flexible film material 8 via an optical adhesive layer. (Comparison) Figure 7 and Figure 8 , Figure 7 The structure shown has strong impact resistance and friction resistance. Figure 8 The structure shown has a high stiffness in the non-bending region, while... Figure 10 The structure shown in the diagram reduces the overall thickness of the display module.

[0085] refer to Figure 5 The tensile stress is greatest in the bending initiation zone (i.e., the transition zone 30), meaning the risk of peeling during bending is greatest. Simultaneously, the compressive stress is greatest at the point of minimum curvature (i.e., the bending zone 10). The transition zone 30 is... Figure 6 As shown in segments BC and C'B', considering the peeling risk of the transition region 30, the transition region 30 is completely filled by the third optical resin coating 6 (i.e., the transition region 30 includes only the third optical resin coating 6, see reference). Figure 6 and Figure 7Considering that the maximum compressive stress during bending (i.e., the bending zone 10) is in segments CO and OC', and based on the fundamental knowledge of inorganic materials, the compressive stress resistance of glass is 10 times its tensile stress resistance. Therefore, segments CO and OC' are filled with a flexible second film 7. In other words, the bending zone 10 uses a combination of the first optical resin coating 2 and the second flexible film 7 (the thickness of the second flexible film 7 can be less than or equal to 70 μm, but is not limited thereto). Considering that the non-bending zone 20, i.e., segments AB and B'A', is not affected by the bending radius and number of bends during bending, a thicker conventional cover glass (i.e., the glass substrate 1, the thickness of which can be greater than or equal to 300 μm, but is not limited thereto) is selected. This solution satisfies both the high impact strength of the non-bending zone 20 and the bending strength of the bending zone 10, while also mitigating the risk of peeling due to excessive tensile stress during bending in the transition zone 30 through the third optical resin coating 6.

[0086] refer to Figure 18 It should be noted that the point of greatest tensile stress during bending is located in the arc-forming area of ​​the water droplet (see reference). Figure 18 The area between the two dashed lines (the region between the two dashed lines), the arc length of the arc-starting area is L:

[0087] Where α is the angle at which the cover plate bends into a teardrop shape; r is the radius of the teardrop's arc, as referenced. Figure 18 .

[0088] It should be noted that, Figure 6 The minimum value of the BC segment (i.e., the transition zone) in the Y direction is L (i.e., the minimum value of the transition zone in the Y direction, which is perpendicular to the direction from the bending zone to the non-bending zone). That is, the length a of the BC segment is greater than or equal to L. When the width of the BC segment in the Y direction is greater than or equal to the arc length of the teardrop-shaped arc-starting zone, an optical resin coating (i.e., the third optical resin coating) is applied to the area corresponding to the entire arc-starting zone to avoid the risk of peeling due to excessive local tensile stress in that area during bending.

[0089] For example, the third optical resin coating 6 and the first optical resin coating 2 can be integrally formed using a synchronous process, and the second optical resin coating 3, the first optical resin coating 2, and the third optical resin coating 6 can be integrally formed using a synchronous process to ensure the flatness of the second side of the cover plate, so that the cover plate forms a complete teardrop-shaped flexible cover plate when folded.

[0090] For example, the second side of the cover plate body is used to connect to the display panel, and the second flexible film 7 is made of ultra-thin glass.

[0091] The first side of the cover plate body is located away from the display panel, and the second flexible film material 7 is made of ultra-thin glass, which can enhance the impact resistance of the bending area 10 while ensuring the bending performance of the bending area 10.

[0092] For example, the thickness of the second flexible membrane 7 is less than or equal to 70 μm.

[0093] refer to Figures 11-15 For example, the glass substrate 1 includes a side surface 103 disposed near the bending region 10 and a light-incident surface 102 and a light-exit surface 101 adjacent to the side surface 103. The light-incident surface 102 is used to receive light emitted by the display panel.

[0094] The edges where the light-emitting surface 101 intersects with the side surface 103 are chamfered or rounded, and / or the edges where the light-incident surface 102 intersects with the side surface 103 are chamfered or rounded.

[0095] Chamfering or rounding, compared to right angles, can prevent uneven brightness.

[0096] Figure 11 In this configuration, the edges where the light-emitting surface 101 intersects with the side surface 103 are chamfered, and the edges where the light-incident surface 102 intersects with the side surface 103 are also chamfered. Wherein, 1t≤a≤1.9t, 0.22t≤b≤0.42t, and 0.16t≤c≤0.56t.

[0097] Figure 14 In this configuration, the edges where the light-emitting surface 101 intersects with the side surface 103 are rounded, and the edges where the light-incident surface 102 intersects with the side surface 103 are also rounded. Wherein 0.1t ≤ g < t, 0.1t ≤ h ≤ 0.8t.

[0098] For example, the end of the glass substrate 1 near the bending area 10 has a cross-section of 1 / 2 ellipse in the thickness direction of the cover plate body, or the end of the glass substrate 1 near the bending area 10 has a cross-section of 1 / 4 ellipse in the thickness direction of the cover plate body, and the 1 / 4 ellipse protrudes in a direction away from the light-incident surface 102.

[0099] Figure 12 In the case of the glass substrate 1, the cross section of the end of the glass substrate 1 near the bending area 10 in the thickness direction of the cover plate body is a 1 / 4 ellipse, wherein the semi-major axis of the 1 / 4 ellipse is d, the semi-minor axis of the 1 / 4 ellipse is e, and 0.5t≤d≤1.5t, 0.5t≤e≤1.5t.

[0100] Figure 13In the case of the glass substrate 1, the cross section of the end near the bending area 10 in the thickness direction of the cover plate body is a 1 / 2 ellipse, wherein the semi-major axis of the 1 / 2 ellipse is f, the semi-minor axis of the 1 / 2 ellipse is f1, 0.5t≤f≤4t, and f1=t.

[0101] refer to Figure 15 For example, in the direction from the non-bending region 20 to the bending region 10, the light-emitting surface 101 of the glass substrate 1 includes a planar portion 1011, a beveled portion 1012, and an arcuate portion 1013, wherein the arcuate portion 1013 is formed by rounding the corners at the intersection of the light-emitting surface 101 and the side surface 103; and / or, in the direction from the non-bending region 20 to the bending region 10, the light-incident surface 102 of the glass substrate 1 includes a planar portion, a beveled portion, and an arcuate portion, wherein the arcuate portion is formed by rounding the corners at the intersection of the light-incident surface 102 and the side surface 103.

[0102] For example, the light-emitting surface 101 and the light-incident surface 102 of the glass substrate 1 are symmetrically arranged.

[0103] For example, the first optical resin coating 2, the second optical resin coating 3, and the third optical resin coating 6 are made of the same material, and the difference between the refractive index of the first optical resin coating 2 and the refractive index of the glass substrate 1 is less than or equal to 0.01, so as to avoid the generation of interface marks at the junction of any two adjacent structures among the glass substrate 1, the first optical resin coating 2, the second optical resin coating 3, and the third optical resin coating 6.

[0104] For example, the refractive index of the first optical resin coating 2 is n, 1.50≤n≤1.54, but is not limited thereto.

[0105] For example, the transmittance of the first optical resin coating 2 is greater than or equal to 90%.

[0106] For example, the material of the first optical resin coating 2 is one or more of the following: polyester, polyurethane, thermoplastic polyurethane, polyamide, polyimide, polymethyl methacrylate, polypropylene, polyethylene, polypropylene, polyvinyl chloride, polystyrene, styrene, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polysulfone, polyaryletherketone, styrene, polyolefin, polyolefin.

[0107] The following is Figure 3 Taking the structure of the cover plate shown as an example, samples with different parameters were selected and compared with the cover plate made of only ultra-thin glass in related technologies.

[0108] First sample: The thickness of the glass substrate 1 is 100 μm, and the edge of the glass substrate 1 is... Figure 11 The first flexible film material 4 is made of ultra-thin glass (UTG) with a thickness of 30 μm. The first flexible film material 4 is connected to the glass substrate 1 by optical adhesive (OCA) with a thickness of 50 μm. The first optical resin coating 2 is composed of polyurethane, dimethylformamide, butyl acetate, styrene-trimethoxysilane coupling agent, defoamer and leveling agent, with a composition mass ratio of 60:130:30:10:1:1. The refractive index of the first optical resin coating is 1.513.

[0109] The second sample: the thickness of the glass substrate 1 is 200 μm, and the edge of the glass substrate 1 is... Figure 11 The first flexible film 4 is made of ultra-thin glass with a thickness of 30 μm. The first flexible film 4 is connected to the glass substrate 1 by optical adhesive (OCA) with a thickness of 50 μm. The first optical resin coating 2 is composed of polyurethane, dimethylformamide, butyl acetate, styrene-trimethoxysilane coupling agent, defoamer and leveling agent, with a composition mass ratio of 60:130:30:10:1:1. The refractive index of the first optical resin coating is 1.513.

[0110] The third sample: the thickness of the glass substrate 1 is 100 μm, and the edge of the glass substrate 1 is... Figure 11 The first flexible film 4 is made of ultra-thin glass with a thickness of 50 μm. The first flexible film 4 is connected to the glass substrate 1 by optical adhesive (OCA) with a thickness of 50 μm. The first optical resin coating 2 is composed of polyurethane, dimethylformamide, butyl acetate, styrene-trimethoxysilane coupling agent, defoamer and leveling agent, with a composition mass ratio of 60:130:30:10:1:1. The refractive index of the first optical resin coating is 1.513.

[0111] The fourth sample: The thickness of the glass substrate 1 is 100 μm, and the edge of the glass substrate 1 is... Figure 11 The first flexible film 4 is made of PET with a thickness of 50 μm. The first flexible film 4 is connected to the glass substrate 1 by optical adhesive (OCA) with a thickness of 50 μm. The first optical resin coating 2 is composed of polyurethane, dimethylformamide, butyl acetate, styrene-trimethoxysilane coupling agent, defoamer and leveling agent, with a composition mass ratio of 60:130:30:10:1:1. The refractive index of the first optical resin coating is 1.513.

[0112] Comparative sample 1 in the related technology: The cover is made of ultra-thin glass with a thickness of only 30um.

[0113] Comparative sample 2 in the related technology: The cover is made of only ultra-thin glass with a thickness of 70um.

[0114] It should be noted that the test surfaces of the first and second samples are both the side without the first flexible film 4, while the test surfaces of the third and fourth samples are both the side of the first flexible film 4 away from the glass substrate 1. Furthermore, no other film layers were attached to the outer surface (i.e., the test surface) of any of the first, second, third, and fourth samples during the impact test.

[0115] It should be noted that the first to fourth samples include the assembled cover plate and display panel. The bending area of ​​the first to fourth samples is equipped with the first optical resin coating, and the non-bending area is equipped with a thicker glass substrate. During the test, if either a bright spot appears on the test sample or the glass substrate breaks, the corresponding result will be recorded.

[0116] It should be noted that during the impact test, both Comparative Sample 1 and Comparative Sample 2 had an 80µm thick CPI film and a 50µm thick OCA film bonded to their outer surfaces (the comparative samples included a CPI film layer on the first side of the ultra-thin glass via OCA and a PET layer on the second side of the ultra-thin glass via OCA). Their test results are shown in the table below:

[0117]

[0118] The pen-drop test was conducted using a Chenguang pen, and the evaluation criteria were the breakage of the ultra-thin glass or the glass substrate (the evaluation criteria for the comparison sample was the breakage of the ultra-thin glass, and the evaluation criteria for the first to fourth samples were the appearance of bright spots or the breakage of the glass substrate). The test method is as follows:

[0119] Select test points and drop a 12g (5mm tip diameter) M&G pen with the tip facing down from a specified height. The test starts at a height of 0.5cm and is repeated in increments of 0.5cm. For the comparison sample, record the drop height at which CPI indentation and ultrathin cracks occur. For the first to fourth samples, record the drop height at which bright spots or glass substrate cracks appear.

[0120] After the pen impact test, inspect the appearance of the cover plate and record the test results;

[0121] Select different test points, conduct tests through the above steps, and record the test results.

[0122] In the table above, for the first sample, when tested in the bending area, a bright spot appeared when dropped from a height of 15cm. For the non-bending area, when tested from a height of 50cm, a bright spot appeared or the glass substrate shattered. For comparison sample 1, the ultra-thin glass shattered when tested in different areas from a height of 18cm.

[0123] During the extrusion test, the evaluation criterion for the comparison sample was the shattering of the ultra-thin glass, while the evaluation criterion for the first to fourth samples was the appearance of bright spots or shattering of the glass substrate on the evaluation equipment. The evaluation equipment was an extrusion testing machine, and the test indenter was a spherical indenter with a diameter of 1.2 mm (the indenter material was stainless steel).

[0124] During testing, multiple test points were selected. For each test point, the test indenter was brought close to the sample at a speed of 10 mm / min. After contact with the sample, loads of 1 kg, 1.5 kg, 2 kg, etc., were applied, with each test point held for 10 seconds. For the control sample, the load at which the ultra-thin glass shattered was recorded. For the first to fourth samples, the loads at which bright spots appeared or the glass substrate shattered were recorded. In the table above, for the first sample, the load corresponding to the bright spots in the bending area was 19 kg, and for the non-bending area, the load corresponding to the bright spots or glass substrate shattering was 46 kg. For control sample 1, the test results for different areas all showed that the ultra-thin glass shattered at 8 kg.

[0125] When conducting pencil hardness testing, the evaluation standard is a pencil hardness greater than or equal to 7. The evaluation equipment is a pencil hardness tester, and the testing method is as follows: Before testing, check the product's appearance for defects such as discoloration, bubbles, cracks, and peeling, and wipe the sample surface clean with a lint-free cloth; sharpen the triangular pencil lead into a cylinder with a diameter of 3mm, hold the pencil so that the end face of the pencil lead is perpendicular to 400-grit sandpaper at a 90-degree angle, and then slowly draw circles until the end face of the lead is flat and the four edges are sharp; place the sample to be tested on a horizontal and stable surface, insert the sharpened pencil into the testing instrument, and the pencil lead... The head contacts the test surface of the sample at a 45-degree angle and draws five lines at a pressure of 1 kgf, a speed of 10 ± 2.5 mm / s, and a stroke of 30 mm. Only one line is allowed to be unqualified (a scratch on the test surface indicates unqualification). For example, if all five lines are qualified or one line is unqualified when the pencil hardness is 9H, then the pencil hardness of the test sample is greater than or equal to 9H. If the number of unqualified lines is greater than or equal to two, then the pencil hardness of the test sample is less than 9H. The data in the table are the maximum allowable pencil hardness for the test sample.

[0126] When conducting dynamic bending tests, the evaluation criteria are that the laminated structure shifts or the glass substrate (for the comparison sample, it is ultra-thin glass) breaks. For example, in the table above, the first sample has a minimum bending radius of 2mm after 200,000 dynamic bending cycles, while the comparison sample 1 has a minimum bending radius of 0.5mm after 200,000 dynamic bending cycles.

[0127] As can be seen from the table above, by combining different structures, compared with the structure of only using ultra-thin glass in related technologies, the cover plate of this embodiment has strong bending performance in the bending area and strong impact resistance in the non-bending area, thus solving the problem of not being able to balance bending performance and impact resistance.

[0128] As can be seen from the table above, the corresponding performance of different areas of the cover plate can be achieved by adjusting parameters such as the thickness of the corresponding structure and the materials used.

[0129] refer to Figures 8-10 This disclosure also provides a display module, including a display panel 100 and the aforementioned cover plate located on the light-emitting side of the display panel 100.

[0130] For example, the display panel 100 includes a bonding area, which is bent to the backlight side of the display panel 100 to bond and connect with the main circuit board, and a protective adhesive layer 200 is provided on the side of the bonding area near the cover plate;

[0131] The orthographic projection of the binding area on the cover plate completely coincides with the cover plate, or the orthographic projection of the binding area on the cover plate is located in a first region of the cover plate, the cover plate including an edge region exposed outside the first region.

[0132] In foldable products of related technologies, due to the flexibility of the cover plate, if the cover plate is flush with or extends outward relative to the bending area (bonding area) of the display panel, there is a risk of the cover plate sticking to the MCL adhesive (i.e., the protective adhesive layer 200) after the Pad Bending process, leading to display abnormalities and other problems. Therefore, in related technologies, the edge of the cover plate is recessed relative to the edge of the bonding area. Although this structural design avoids the risk of the cover plate sticking to the protective adhesive layer 200, on the one hand, it exposes the protective adhesive layer 200 and the bonding area to the outer edge, which still poses a risk of impact during subsequent processes such as assembly. On the other hand, during assembly, the mid-frame 300 covers the surface of the cover plate 400 from top to bottom (the mid-frame 300 covers part of the cover plate 400), which is equivalent to the screen being recessed into the mid-frame 300, affecting aesthetics and screen-to-body ratio. Figure 16 .

[0133] To address the aforementioned issues, compared to cover plates made of ultra-thin glass, this embodiment uses a glass substrate 1 (with a thickness greater than or equal to 300 μm) in the non-bending area 20, which has superior rigidity and stiffness compared to ultra-thin glass. The edge of the cover plate can be flush with or appropriately extended from the edge of the bonding area, meaning that the orthographic projection of the bonding area on the cover plate completely coincides with the cover plate, or the orthographic projection of the bonding area on the cover plate is located in a first region of the cover plate, and the cover plate includes an edge region exposed outside the first region. This provides strong support for the cover plate, eliminating the need to consider the adhesion between the cover plate and the protective adhesive layer 200; and effectively protects the bonding area from impact during subsequent processes such as assembly.

[0134] refer to Figure 17 For example, the cover 400 includes an edge region exposed around the first region, and the middle frame 300 of the display module is connected to the edge region on the side closer to the display panel.

[0135] When assembling the mid-frame, it can be considered to snap it inward from the back onto the cover plate, that is, the entire mid-frame is located on the backlight side of the cover plate, thereby increasing the screen ratio of the whole device.

[0136] This disclosure also provides a display device, including the display module described above.

[0137] It is understood that the above embodiments are merely exemplary embodiments used to illustrate the principles of this disclosure, and this disclosure is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this disclosure, and these modifications and improvements are also considered to be within the scope of protection of this disclosure.

Claims

1. A cover plate, wherein, The cover plate includes a main body, the main body of which includes a bending area and non-bending areas located on both sides of the bending area, the non-bending areas including a glass substrate, and the bending area including a first optical resin coating formed by a coating process using an optical resin material; The cover plate body includes a first side and a second side disposed opposite to each other along its thickness direction. From the first side to the second side, the non-bending area includes the glass substrate and a second optical resin coating applied to the glass substrate. The first optical resin coating has a first surface located on the second side, and the second optical resin coating has a second surface located on the second side, with the first surface and the second surface located on the same plane; The cover plate body also includes a transition area located between the bending area and the non-bending area, the transition area including a third optical resin coating, the third optical resin coating including a fifth surface located on the second side, the fifth surface being located on the same plane as the second surface; The glass substrate has a third surface located on the first side, and the third optical resin coating includes a sixth surface located on the first side, the sixth surface being in the same plane as the third surface.

2. The cover plate according to claim 1, wherein, The glass substrate has a third surface located on the first side, and the first optical resin coating includes a fourth surface located on the first side, wherein the third surface and the fourth surface are located in the same plane.

3. The cover plate according to claim 2, wherein, The first side of the cover plate body is bonded with a first flexible film material through an optical adhesive layer, and / or the second side of the cover plate body is bonded with a first flexible film material through an optical adhesive layer.

4. The cover plate according to claim 3, wherein, The first flexible membrane material is made of PET, CPI, PMMA or ultra-thin glass.

5. The cover plate according to claim 4, wherein, The thickness of the first flexible membrane material is less than or equal to 20 μm.

6. The cover plate according to claim 1, wherein, In the direction from the first side to the second side, the bending region includes a second flexible film and the first optical resin coating applied to the second flexible film.

7. The cover plate according to claim 6, wherein, The second flexible membrane material is made of PET, CPI, PMMA or ultra-thin glass.

8. The cover plate according to claim 6, wherein, The thickness of the second flexible membrane is less than or equal to 70 μm.

9. The cover plate according to claim 1, wherein, The first side of the cover plate body is bonded with a third flexible film material through an optical adhesive layer; or the second side of the cover plate body is bonded with a third flexible film material through an optical adhesive layer.

10. The cover plate according to claim 9, wherein, The third flexible membrane material is made of PET, CPI, PMMA or ultra-thin glass.

11. The cover plate according to claim 1, wherein, The thickness of the glass substrate is greater than or equal to 300 μm.

12. The cover plate according to claim 1, wherein, The glass substrate includes a side surface disposed near the bending area and a light-incident surface and a light-outcident surface adjacent to the side surface, wherein the light-incident surface is used to receive light emitted by the display panel; The edge where the light-emitting surface intersects with the side surface is chamfered or rounded, and / or the edge where the light-incident surface intersects with the side surface is chamfered or rounded.

13. The cover plate according to claim 12, wherein, The glass substrate has a 1 / 2 elliptical cross section in the thickness direction of the cover plate body at one end near the bending area, or the glass substrate has a 1 / 4 elliptical cross section in the thickness direction of the cover plate body at one end near the bending area, and the 1 / 4 elliptical cross section protrudes in a direction away from the light-incident surface.

14. The cover plate according to claim 12, wherein, In the direction from the non-bending area to the bending area, the light-emitting surface of the glass substrate includes a planar portion, a beveled portion, and a curved portion, wherein the curved portion is formed by rounding the corners at the intersection of the light-emitting surface and the side surface; and / or, in the direction from the non-bending area to the bending area, the light-incident surface of the glass substrate includes a planar portion, a beveled portion, and a curved portion, wherein the curved portion is formed by rounding the corners at the intersection of the light-incident surface and the side surface.

15. The cover plate according to claim 1, wherein, The first optical resin coating, the second optical resin coating, and the third optical resin coating are made of the same material, and the difference between the refractive index of the first optical resin coating and the refractive index of the glass substrate is less than or equal to 0.

01.

16. The cover plate according to claim 15, wherein, The refractive index of the first optical resin coating is n, where 1.50 ≤ n ≤ 1.

54.

17. The cover plate according to claim 15, wherein, The transmittance of the first optical resin coating is greater than or equal to 90%.

18. The cover plate according to claim 15, wherein, The material of the first optical resin coating is one or more of the following: polyester, polyurethane, thermoplastic polyurethane, polyamide, polyimide, polymethyl methacrylate, polypropylene, polyethylene, polypropylene, polyvinyl chloride, polystyrene, styrene, polyoxymethylene, polyphenylene ether, polyphenylene sulfide, polysulfone, polyaryletherketone, styrene, polyolefin, and polyolefin.

19. A display module, wherein, Includes a display panel and a cover plate as described in any one of claims 1-18 located on the light-emitting side of the display panel.

20. The display module according to claim 19, wherein, The display panel includes a bonding area, which is bent to the backlight side of the display panel to bond with the main circuit board. A protective adhesive layer is provided on the side of the bonding area near the cover plate. The orthographic projection of the binding area on the cover plate completely coincides with the cover plate, or the orthographic projection of the binding area on the cover plate is located in a first region of the cover plate, the cover plate including an edge region exposed outside the first region.

21. The display module according to claim 20, wherein, The cover plate includes an edge region exposed outside the first region, and the middle frame of the display module is connected to the side of the edge region near the display panel.

22. A display device, wherein, Includes the display module as described in any one of claims 19-21.

Images