Cover plate, display module, foldable electronic device, and preparation method for cover plate

Abstract

The present application provides a cover plate, a display module, a foldable electronic device, and a preparation method for the cover plate. The cover plate comprises a substrate layer, a bonding layer and an elastic material layer. The substrate layer comprises a first portion, a second portion and a bendable portion, wherein the bendable portion is connected between the first portion and the second portion. The substrate layer is provided with a first hole, and the opening of the first hole is formed on a surface of the bendable portion in the thickness direction. The bonding layer is bonded to the hole wall surface of the first hole. The elastic material layer is connected to the side of the bonding layer facing away from the hole wall surface of the first hole. The cover plate of the present application can have both impact resistance and excellent bending performance, and has good prospects for application.

Description

Cover plate, display module, foldable electronic device, and method for preparing cover plate

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 27, 2023, with application number 202311811057.5 and application name “Cover, display module, foldable electronic device and method for preparing cover”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the technical field of electronic devices, and in particular to a cover plate, a display module, a foldable electronic device, and a method for preparing the cover plate. Background Art

[0003] In recent years, electronic devices such as foldable phones have become a new growth opportunity for the mobile phone industry. Consumers have higher expectations for thinner, lighter, and higher-quality features. Due to the relative fragility of their display panels, existing foldable phones often utilize cover panels to protect them. However, the thickness of the cover panel is generally proportional to its impact resistance and inversely proportional to its bending performance. Therefore, current cover panels struggle to achieve both impact resistance and excellent bending performance.

[0004] Summary of the Invention

[0005] The purpose of the embodiments of the present application is to provide a cover plate, a display module, a foldable electronic device and a method for preparing the cover plate, wherein the cover plate can have both impact resistance and excellent bending performance.

[0006] An embodiment of the present application provides a cover plate, which includes a substrate layer, an adhesive layer and an elastic material layer. The substrate layer includes a first part, a second part and a bendable part. The bendable part is connected between the first part and the second part. The substrate layer is provided with a first opening. The opening of the first opening is provided on a surface of the bendable part along the thickness direction. The adhesive layer is bonded to the hole wall surface of the first opening. The elastic material layer is connected to the side of the adhesive layer facing away from the hole wall surface of the first opening.

[0007] In the cover plate provided in the embodiments of the present application, by providing a first opening at the bendable portion of the substrate layer and filling the first opening with an elastic material layer, the stress at the bendable portion of the substrate layer can be fully released, thereby resolving the stress concentration problem caused by bending in the bendable portion. This allows the cover plate to achieve a target bending radius when bent, while also facilitating a higher number of bends, resulting in an excellent bending capability. This reduces the risk of creases or cracks in the cover plate caused by bending, thereby facilitating improvements in display module peeling, display failure, and leaks and bubbles in the display module during assembly. Furthermore, the filled elastic material layer can fully withstand stress risks, giving the cover plate high impact resistance.

[0008] In addition, by providing an adhesive layer on the wall surface of the first opening and connecting the elastic material layer to the adhesive layer, on the one hand, the adhesive layer can fix the elastic material layer to prevent the elastic material layer from detaching from the first opening; on the other hand, the adhesive layer can bear part of the stress, which is beneficial to enhancing the bending resistance of the cover plate; on the other hand, the adhesive layer can bond the elastic material layer to the wall surface of the opening, which can avoid the formation of gaps between the elastic material layer and the wall surface of the opening, thereby avoiding the formation of bubbles in the cover plate and avoiding the generation of interference fringes or moiré patterns when light passes through the bubbles, which is beneficial to improving the appearance and light transmission effect of the cover plate.

[0009] In one possible embodiment, the cover plate further includes a protective layer disposed on the surface of the substrate layer and covering the opening of the first opening. On one hand, the protective layer protects the substrate layer while also improving the vertical impact strength of the cover plate, addressing issues such as increased risk of process fragmentation, substrate edge collapse, and low production yields caused by a thin substrate layer. Furthermore, the protective layer covering the opening of the first opening can encapsulate the first opening, preventing the elastic material layer filling the first opening from overflowing under extreme conditions such as high temperatures.

[0010] In one possible embodiment, the paint film hardness of the protective layer is ≥3H, which can improve the problem of poor impact resistance of the substrate layer against the outside world, thereby improving the reliability and service life of the cover plate, and facilitating the application of the cover plate in various practical usage scenarios such as impact and falling.

[0011] In one possible embodiment, the cover plate further includes a first support portion connected to the surface of the bottom wall of the first opening and extending away from the bottom wall of the first opening. The elastic material layer is disposed around the first support portion and covers the circumference of the first support portion. By adding the first support portion extending away from the bottom wall of the first opening within the first opening, the first support portion can support and withstand vertical stress applied to the cover plate, thereby further enhancing the cover plate's high vertical impact resistance.

[0012] In a possible implementation, the elastic modulus of the first supporting portion is greater than the elastic modulus of the elastic material layer.

[0013] In a possible implementation, the elastic modulus of the first support portion is greater than or equal to 500 MPa.

[0014] In a possible embodiment, the surface of the first supporting portion facing away from the bottom wall of the first opening is lower than the opening of the first opening, or the surface of the first supporting portion facing away from the bottom wall of the first opening is flush with the opening of the first opening.

[0015] In one possible embodiment, the cover plate further includes a second support portion connected to a surface of the adhesive layer facing away from the sidewall of the first opening and extending in a direction away from the sidewall of the first opening. The elastic material layer is disposed around the second support portion and covers the circumference of the second support portion. By adding the second support portion extending away from the sidewall of the first opening within the first opening, the second support portion can support and withstand lateral stress applied to the cover plate, thereby further enhancing the cover plate's high lateral impact resistance.

[0016] In a possible implementation, the elastic modulus of the second supporting portion is greater than the elastic modulus of the elastic material layer.

[0017] In a possible implementation manner, the elastic modulus of the second support portion is greater than or equal to 500 MPa.

[0018] In one possible embodiment, the second support portion includes a first support portion and a second support portion, both of which are connected to the sidewall of the first opening, and are spaced apart from each other. When the cover plate is folded, the first support portion and the second support portion can abut against each other, allowing the second support portion to support and withstand horizontal lateral stress applied to the cover plate, thereby further enhancing the cover plate's high lateral bending resistance.

[0019] In a possible embodiment, the surface of the second supporting portion facing away from the bottom wall of the first opening is lower than the opening of the first opening, or the surface of the second supporting portion facing away from the bottom wall of the first opening is flush with the opening of the first opening.

[0020] In a possible implementation, there are multiple first openings, and the multiple first openings are spaced apart from each other and arranged in an array.

[0021] In a possible implementation, the elastic modulus of the elastic material layer is 3 MPa to 300 MPa, and / or the elongation at break of the elastic material layer is greater than 120%.

[0022] In a possible embodiment, a surface of the elastic material layer facing away from the bottom wall of the first opening is flush with the opening of the first opening.

[0023] In a possible implementation, the elastic modulus of the bonding layer is greater than or equal to 80 MPa.

[0024] In a possible embodiment, a surface of the adhesive layer facing away from the bottom wall of the first opening is flush with the opening of the first opening.

[0025] In one possible embodiment, the cover plate further includes a reinforcement portion, which is disposed within the first opening and connected to a side of the adhesive layer facing away from the wall of the first opening. The adhesive layer is disposed around the reinforcement portion and at least partially covers the circumference of the reinforcement portion. The reinforcement portion is provided with filling holes, the openings of the filling holes being disposed on the surface of the reinforcement portion, and the elastic material layer is filled within the filling holes. The reinforcement portion is provided with a plurality of filling holes, so that the reinforcement portion forms a mesh structure. By disposing the reinforcement portion within the first opening and filling the filling holes of the reinforcement portion with the elastic material layer, the reinforcement portion and the elastic material layer form a highly resistant bending structure, thereby enabling the cover plate to simultaneously achieve high lateral flexural resistance and high vertical impact resistance. In addition, by disposing the adhesive layer around the reinforcement portion and covering the circumference of the reinforcement portion, so that the gap between the wall of the first opening and the reinforcement portion is filled with the adhesive layer, the aggravation of microcrack damage that may occur during the formation of the reinforcement portion having a mesh structure can be reduced, thereby further enhancing the high lateral flexural resistance and high vertical impact resistance of the cover plate.

[0026] In a possible implementation, the first opening passes through at least one side surface of the bendable portion along the length direction.

[0027] In a possible implementation, the first opening passes through the bendable portion along the thickness direction.

[0028] In a possible embodiment, the opening of the filling hole is provided on the surface of the reinforcement portion facing the opening of the first opening, so as to facilitate filling the elastic material layer into the filling hole of the reinforcement portion after the reinforcement portion is fixed.

[0029] In a possible implementation, the elastic modulus of the reinforcement portion is greater than the elastic modulus of the elastic material layer.

[0030] In a possible implementation, the elastic modulus of the reinforcement portion is greater than or equal to 500 MPa.

[0031] In one possible embodiment, the bendable portion includes a first surface and a second surface disposed opposite each other along the thickness direction. The substrate layer further includes a second opening, with the opening of the first opening located on the first surface and the second opening located on the second surface. The adhesive layer is further bonded to the wall of the second opening, and the elastic material layer is connected to the side of the adhesive layer facing away from the wall of the second opening. The simultaneous provision of the first and second openings facilitates excellent bending resistance when the cover is folded inwardly or outwardly.

[0032] In one possible embodiment, the cover plate further includes a first support portion connected to the surface of the bottom wall of the second opening and extending away from the bottom wall of the second opening. The elastic material layer is disposed around the first support portion and covers the circumference of the first support portion. By adding the first support portion extending away from the bottom wall of the second opening within the second opening, the first support portion can support and withstand vertical stress applied to the cover plate, thereby further enhancing the cover plate's high vertical impact resistance.

[0033] In one possible embodiment, the cover plate further includes a second support portion connected to a surface of the adhesive layer facing away from the sidewall of the second opening and extending in a direction away from the sidewall of the second opening. The elastic material layer is disposed around the second support portion and covers the circumference of the second support portion. By adding the second support portion extending away from the sidewall of the second opening within the second opening, the second support portion can support and withstand lateral stress applied to the cover plate, thereby further enhancing the cover plate's high lateral impact resistance.

[0034] In a possible embodiment, the cover plate also includes a reinforcement portion, which is arranged in the second opening and connected to the side of the hole wall of the adhesive layer facing away from the second opening. The adhesive layer is arranged around the reinforcement portion and at least partially covers the circumference of the reinforcement portion. The reinforcement portion is provided with a filling hole, the opening of the filling hole is arranged on the surface of the reinforcement portion, and the elastic material layer is filled in the filling hole.

[0035] In a possible implementation, the second opening passes through a side surface of the bendable portion along the length direction.

[0036] In a possible implementation manner, the opening of the filling hole is provided on a surface of the reinforcement portion facing the opening of the second opening.

[0037] An embodiment of the present application further provides a display module, comprising a display panel and the cover plate as described above, wherein the cover plate is mounted on the display panel.

[0038] An embodiment of the present application also provides a foldable electronic device, including a housing and a display module as described above, wherein the display panel is mounted on the housing, and the cover is mounted on a side of the display panel facing away from the housing.

[0039] The present invention also provides a method for preparing a cover plate, including:

[0040] Taking a substrate layer, preparing a first photoresist layer on the surface of the substrate layer, taking a first mask and placing it on the side of the first photoresist layer facing away from the substrate layer, and exposing the first photoresist layer by light through the first mask;

[0041] developing the exposed first photoresist layer to expose a portion of the surface of the substrate layer;

[0042] Etching the surface of the exposed substrate layer to form a first opening;

[0043] Disposing an adhesive layer on the wall surface of the first opening, and removing the developed first photoresist layer;

[0044] An elastic material layer is arranged on the side of the adhesive layer facing away from the hole wall surface of the first opening.

[0045] In one possible embodiment, between the steps of etching the surface of the exposed substrate layer to form the first opening, providing a bonding layer on the wall surface of the first opening, and removing the developed first photoresist layer, the method further includes: providing a second photoresist layer on the wall surface of the first opening, placing a first mask on a side of the second photoresist layer facing away from the substrate layer, and exposing the second photoresist layer by light through the first mask;

[0046] Removing the exposed second photoresist layer to expose the first opening can improve the manufacturing yield of the first opening, thereby effectively improving the manufacturing yield of the cover plate.

[0047] In one possible embodiment, the cover plate further includes a first supporting portion, and an adhesive layer is provided on the wall surface of the first opening. Between the step of removing the developed first photoresist layer and the step of providing an elastic material layer on a side of the adhesive layer facing away from the wall surface of the first opening, the step of providing the first supporting portion in the first opening is further included:

[0048] Disposing a third photoresist layer on the side of the bonding layer away from the hole wall of the first opening, placing a second mask on the side of the third photoresist layer away from the hole bottom wall of the first opening, and exposing the third photoresist layer by light through the second mask;

[0049] developing the exposed third photoresist layer to form a first hole in the third photoresist layer, and filling the first hole with a material of the first support portion;

[0050] The developed third photoresist layer is removed.

[0051] In a possible embodiment, the cover plate further includes a second supporting portion, and after the step of removing the exposed second photoresist layer to expose the first opening, the step further includes disposing the second supporting portion in the first opening:

[0052] Disposing a fourth photoresist layer on a side of the elastic material layer away from the bottom wall of the first opening, placing a third mask on a side of the fourth photoresist layer away from the bottom wall of the first opening, and exposing the fourth photoresist layer by light through the third mask;

[0053] developing the exposed fourth photoresist layer to form a second hole in the fourth photoresist layer, and filling the second hole with a material of the second support portion;

[0054] The developed fourth photoresist layer is removed. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0056] FIG1 is a schematic structural diagram of a foldable electronic device in an unfolded state provided by a first embodiment of the present application;

[0057] FIG2 is a schematic structural diagram of the foldable electronic device shown in FIG1 in a folded state;

[0058] FIG3 is a schematic cross-sectional view of a display module in the foldable electronic device shown in FIG1 in a first example;

[0059] FIG4 is a partial enlarged view of portion A of the display module shown in FIG3 ;

[0060] FIG5 is a schematic top view of the structure of the substrate layer in the cover plate of the display module shown in FIG3 ;

[0061] FIG6 is a schematic cross-sectional view of a bendable cover plate portion of a cover plate with different first opening shapes in some other examples;

[0062] FIG7 is a schematic top view of the structure of a substrate layer with different first opening shapes in some other examples;

[0063] FIG8 is a schematic diagram of the forces acting on the cover plate in the folded state in section A shown in FIG4 ;

[0064] FIG9 is a schematic cross-sectional view of a partial structure of a cover plate in a second example;

[0065] FIG10 is a partial preparation flow chart of the cover plate of the second example shown in FIG9 ;

[0066] FIG11 is a flow chart showing another portion of the preparation of the cover plate of the second example shown in FIG9 ;

[0067] FIG12 is a schematic cross-sectional view of a partial structure of a cover plate in a third example;

[0068] FIG13 is a schematic diagram of the force acting on portion B of the structure shown in FIG12 when subjected to an extrusion force;

[0069] FIG14 is a partial preparation flow chart of the cover plate shown in FIG12 ;

[0070] FIG15 is a schematic top view of the cover plate in the fourth example;

[0071] FIG16 is a schematic diagram of the cross-sectional structure of the cover plate in the fifth example;

[0072] FIG17 is a schematic top view of the structure of the cover plate shown in FIG16 with the filling layer filled in the opening;

[0073] FIG18 is a perspective exploded schematic diagram of the cover plate shown in FIG16 ;

[0074] FIG19 is a schematic top view of the structure of a portion of the cover plate in another example in which the filling layer is filled in the first opening;

[0075] FIG20 is a perspective exploded schematic diagram of a portion of the cover plate shown in FIG19;

[0076] FIG21 is a schematic diagram of the cross-sectional structure of the cover plate in the sixth example;

[0077] FIG22 is a schematic diagram of the top structure of the cover plate shown in FIG21;

[0078] FIG23 is a schematic diagram of the exploded perspective structure of the cover plate shown in FIG21;

[0079] FIG24 is a schematic diagram of a three-dimensional exploded structure of the cover plate in the seventh example;

[0080] FIG25 is a schematic structural diagram of a foldable electronic device in a folded state provided by a second embodiment of the present application;

[0081] FIG26 is a schematic diagram showing the forces acting on various parts of the display module in the foldable electronic device shown in FIG25 when the parts are bent. DETAILED DESCRIPTION

[0082] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0083] Please refer to Figures 1 and 2. Figure 1 is a structural schematic diagram of the foldable electronic device 1000 provided in the first embodiment of the present application when it is in an unfolded state, and Figure 2 is a structural schematic diagram of the foldable electronic device 1000 shown in Figure 1 when it is in a folded state.

[0084] The foldable electronic device 1000 can be a mobile phone, a laptop computer, a tablet computer, or other electronic device. The foldable electronic device 1000 can be folded once, twice, or more times. The foldable electronic device 1000 of the first embodiment is described using a foldable mobile phone that is folded once as an example.

[0085] For the convenience of description, the length direction of the foldable electronic device 1000 shown in Figure 1 is defined as the X-axis direction, the width direction is the Y-axis direction, and the thickness direction is the Z-axis direction. The X-axis direction, the Y-axis direction and the Z-axis direction are perpendicular to each other.

[0086] The foldable electronic device 1000 includes a housing 100 and a display module 300 , wherein the display module 300 is mounted on the housing 100 .

[0087] In this embodiment, the housing 100 includes a first housing 110, a first rotating shaft 120, a second housing 130, and a shaft cover (not shown in Figures 1 and 2). The first rotating shaft 120 is rotatably connected between the first housing 110 and the second housing 130, and the shaft cover is mounted on the first rotating shaft 120. The display module 300 includes a first display portion 301, a first bendable portion 302, and a second display portion 303. The first bendable portion 302 is connected between the first display portion 301 and the second display portion 303. The first display portion 301 is mounted on the first housing 110, the first bendable portion 302 is mounted on the first rotating shaft 120, and the second display portion 303 is mounted on the second housing 130.

[0088] Foldable electronic device 1000 can be in both an unfolded state and a folded state. In the unfolded state, the first housing 110, first hinge 120, and second housing 130 of housing 100 are roughly coplanar, and the hinge cover is roughly flush with the first and second housings 110, 130. The first display portion 301, first bendable portion 302, and second display portion 303 of display module 300 are roughly coplanar, providing a large display area.

[0089] When the foldable electronic device 1000 is in the folded state, the housing 100 and the display module 300 are both bent, and the size of the foldable electronic device 1000 along the X-axis direction is small, making the foldable electronic device 1000 easy to carry. Specifically, the first housing 110 is folded relative to the second housing 130, the first display portion 301 is folded relative to the second display portion 303, and the first bendable portion 302 is bent. As shown in Figure 2, when the foldable electronic device 1000 of this embodiment is in the folded state, the display module 300 is located on the inner side of the housing 100, that is, the foldable electronic device 1000 is an inward-folding electronic device. In other embodiments, when the foldable electronic device 1000 is in the folded state, the display module 300 may also be located on the outer side of the housing 100, that is, the foldable electronic device 1000 may also be an outward-folding electronic device.

[0090] 1 and 3 , FIG3 is a schematic cross-sectional view of the display module 300 in the foldable electronic device 1000 shown in FIG1 in a first example.

[0091] The display module 300 includes a display panel 310 and a cover plate 330. The display panel 310 is mounted on the housing 100, and the cover plate 330 is mounted on the side of the display panel 310 facing away from the housing 100. Exemplarily, the display panel 310 is an OLED (Organic Light-Emitting Diode) display panel. The display panel 310 includes a PI (Polyimide) substrate, a flexible TFT (Thin Film Transistor) circuit board, a thin film encapsulation layer (TFE), a polarizer (POL), and an optically clear adhesive (OCA). The flexible TFT circuit board is provided on the PI substrate, the thin film encapsulation layer is provided on the side of the flexible TFT circuit board facing away from the PI substrate, the polarizer is provided on the surface of the thin film encapsulation layer facing away from the flexible TFT circuit board, and the optical adhesive is bonded between the polarizer and the cover plate 330.

[0092] Specifically, the cover plate 330 includes a substrate layer 10, a filling layer 350, and a protective layer 333. The substrate layer 10 is mounted on the display panel 310, the filling layer 350 is provided on the substrate layer 10, and the protective layer 333 covers the surface of the substrate layer 10 facing away from the display panel 310 and blocks the filling layer 350. It is understood that in other examples, the cover plate 330 may not include the protective layer 333, and the provision of the protective layer 333 may be selected based on actual needs.

[0093] In this example, the cover plate 330 includes a first cover plate portion 330a, a bendable cover plate portion 330b, and a second cover plate portion 330c. The bendable cover plate portion 330b is connected between the first cover plate portion 330a and the second cover plate portion 330c and can be bent. In this example, the first cover plate portion 330a of the cover plate 330 and a portion of the display panel 310 form the first display portion 301, the second cover plate portion 330c and a portion of the display panel 310 form the second display portion 303, and the bendable cover plate portion 330b and a portion of the display panel 310 form the first bendable portion 302.

[0094] When the foldable electronic device 1000 is in the unfolded state, the first cover portion 330a, the bendable cover portion 330b, and the second cover portion 330c of the cover 330 are approximately in the same plane. When the foldable electronic device 1000 is in the folded state, the first cover portion 330a folds relative to the second cover portion 330c, and the bendable cover portion 330b bends.

[0095] 4 and 5 , FIG. 4 is a partial enlarged view of portion A of the display module 300 shown in FIG. 3 , and FIG. 5 is a schematic top view of the substrate layer 10 in the cover plate 330 of the display module 300 shown in FIG. 3 .

[0096] Exemplarily, the material of the substrate layer 10 is ultra-thin glass (UTG), and the thickness of the substrate layer 10 is H1, where H1 is 30 μm to 50 μm. Specifically, the substrate layer 10 includes a first portion 11, a bendable portion 13, and a second portion 12. The bendable portion 13 is connected between the first portion 11 and the second portion 12. When the foldable electronic device 1000 is in the folded state, the first portion 11 of the substrate layer 10 is folded relative to the second portion 12, and the bendable portion 13 is bent.

[0097] The bendable portion 13 includes a first surface 131 and a second surface 133 disposed opposite to each other in the thickness direction. The first surface 131 faces away from the display panel 310, and the second surface 133 faces the display panel 310. Exemplarily, the bendable portion 13 has a width W, which is 1 mm to 20 mm.

[0098] The substrate layer 10 is provided with an opening 15, and the opening of the opening 15 is provided on the surface of the bendable portion 13 of the substrate layer 10. In this example, there are multiple openings 15, and the multiple openings 15 include a first opening 151 and a second opening 153. The opening of the first opening 151 and the opening of the second opening 153 are respectively provided on two surfaces of the bendable portion 13 along the thickness direction. In this example, the opening of the first opening 151 is provided on the first surface 131, that is, the opening of the first opening 151 is provided on the surface of the bendable portion 13 facing away from the display panel 310. The opening of the second opening 153 is provided on the second surface 133, that is, the opening of the second opening 153 is provided on the surface of the bendable portion 13 facing the display panel 310. The first opening 151 is used as an example below. The shape, size and position arrangement of the second opening 153 are similar to those of the first opening 151, and can be arranged with reference to the first opening 151, and will not be repeated here.

[0099] For example, in this example, the depth of the first opening 151 is D1, which is 2 μm to 5 μm, and the width of the first opening 151 is D2, which is 2 μm to 10 μm. As shown in FIG4 , in this embodiment, the shape of the first opening 151 is a truncated cone, and the cross-sectional shape of the first opening 151 is a trapezoid.

[0100] Referring to Figures 6 and 7, Figure 6 is a schematic cross-sectional view of the bendable cover plate portion 330b of the cover plate 330 with different first opening 151 shapes in other examples, and Figure 7 is a schematic top view of the substrate layer 10 with different first opening 151 shapes in other examples. It is understood that in other examples, as shown in Figures 6 and 7, the shape of the first opening 151 can also be a hemisphere (with an arc-shaped cross section) or a cylinder (with a rectangular cross section), etc. This application does not limit the shape of the first opening 151, and it can also be polygonal, anisotropic, or a combination of various shapes.

[0101] Continuing with FIG. 4 , in this example, there may be multiple first openings 151 , with the multiple first openings 151 spaced apart. In this example, the multiple first openings 151 are arranged in an array. Array arrangements include, but are not limited to, uniform arrangement, staggered arrangement, and star-shaped arrangement. For example, the spacing between two adjacent first openings 151 is D3, and D3 is 5 μm to 20 μm.

[0102] In this example, the filling layer 350 is filled in the first opening 151 and the second opening 153 of the bendable portion 13 of the substrate layer 10. Specifically, the filling layer 350 includes an adhesive layer 30 and an elastic material layer 50, and both the adhesive layer 30 and the elastic material layer 50 are filled in the first opening 151 and the second opening 153 of the substrate layer 10. Among them, the adhesive layer 30 of the filling layer 350 is bonded to the hole wall surface of the first opening 151 and the second opening 153, and the elastic material layer 50 is connected to the side of the adhesive layer 30 facing away from the hole wall surface of the first opening 151, and is arranged on the side of the adhesive layer 30 facing away from the hole wall surface of the second opening 153. Among them, the "hole wall surface" includes the hole bottom wall surface and the hole side wall surface. "Connection" includes direct connection and indirect connection. In this example, the elastic material layer 50 is directly bonded to the adhesive layer 30. The surface of the adhesive layer 30 facing away from the bottom wall of the first opening 151 is flush with the opening of the first opening 151, and the surface of the adhesive layer 30 facing away from the bottom wall of the second opening 153 is flush with the opening of the second opening 153, which facilitates the flatness of the cover plate 330. The surface of the elastic material layer 50 facing away from the bottom wall of the first opening 151 is flush with the opening of the first opening 151, and the surface of the elastic material layer 50 facing away from the bottom wall of the second opening 153 is flush with the opening of the second opening 153, which facilitates the flatness of the cover plate 330. It is understood that in other examples, the substrate layer 10 may be provided with only the first opening 151, and the filling layer 350 may be filled only within the first opening 151, or the substrate layer 10 may be provided with only the second opening 153, and the filling layer 350 may be filled only within the second opening 153.

[0103] Exemplarily, the material of the adhesive layer 30 is a light-curing material or a heat-curing material. For example, the material of the adhesive layer 30 includes but is not limited to OCA glue (Optically Clear Adhesive), OCR glue (Optical Clear Resin), UV shadowless glue (Ultraviolet Rays glue), and polyacrylate. In some examples, the elastic modulus of the adhesive layer 30 is greater than or equal to 80 MPa to ensure that the adhesive layer 30 has anti-bending properties while having an adhesive effect, thereby helping to enhance the anti-bending properties of the cover plate 330. It is understandable that the light transmittance of the adhesive layer 30 is generally set to be greater than or equal to 99.5%, which does not affect the transmission of light, thereby ensuring the light transmission effect of the cover plate 330.

[0104] Exemplarily, the elastic material layer 50 is made of a thermoplastic elastic material. For example, the elastic material layer 50 may be made of a polyurethane-based resin, an acrylate-based resin, an epoxy-based resin, or the like. In some examples, the elastic modulus of the elastic material layer 50 is between 3 MPa and 300 MPa, and / or the elongation at break of the elastic material layer 50 is greater than 120%. This allows the elastic material layer 50 to have a high elastic modulus and high elongation at break, thereby enhancing the bending resistance of the cover plate 330.

[0105] For example, when providing the filling layer 350 in the substrate layer 10, a first opening 151 and a second opening 153 may be formed on the surface of the bendable portion 13 of the substrate layer 10. The first opening 151 and the second opening 153 are then filled with the material of the adhesive layer 30, respectively, to bond the adhesive layer 30 to the wall of the opening 15. The first opening 151 and the second opening 153 are then filled with the material of the elastic material layer 50, which are then cured to form the filling layer 350. The adhesive layer 30 is cured to form the adhesive layer 30, and the elastic material layer 50 is cured to form the elastic material layer 50.

[0106] In this example, the protective layer 333 is provided on the surface of the substrate layer 10 facing away from the display panel 310, and covers the opening of the first opening 151 of the substrate layer 10, so as to protect the substrate layer 10 while encapsulating the first opening 151, and prevent the material of the elastic material layer 50 filled in the first opening 151 from overflowing under special conditions such as high temperature, bending, collision or impact. Exemplarily, the thickness of the protective layer 333 is H2, and H2 is 2μm to 10μm. It should be noted that the side of the display panel 310 facing the second opening 153 of the substrate layer 10 is usually provided with a cured OCA glue, which can prevent the material of the elastic material layer 50 filled in the second opening 153 from overflowing and bonding the electronic devices or circuits in the display panel 310.

[0107] Among them, the material of the protective layer 333 is a flexible material, which is beneficial for the protective layer 333 to bend together with the substrate layer 10. For example, the material of the protective layer 333 can be acrylate, methyl methacrylate and epoxy resin. In some examples, the paint film hardness of the protective layer 333 is ≥3H, which can improve the problem of poor impact resistance of the substrate layer 10 against the outside world, thereby improving the reliability and service life of the cover plate 330, and facilitating the cover plate 330 to be used in various practical use scenarios such as impact and fall. Among them, the present application uses the pencil method to measure the paint film hardness of the protective layer 333. In addition, the protective layer 333 can also have AR (Anti-reflection) performance to improve the light transmittance of the cover plate 330.

[0108] In this example, the first part 11 of the substrate layer 10 and the protective layer 333 covering the first part 11 form the first cover part 330a of the cover plate 330, the bendable part 13 of the substrate layer 10, the filling layer 350 provided on the bendable part 13 and the protective layer 333 covering the surface of the bendable part 13 form the bendable cover part 330b of the cover plate 330, and the second part 12 of the substrate layer 10 and the protective layer 333 covering the second part 12 form the second cover part 330c of the cover plate 330.

[0109] Refer to Figure 8, which is a schematic diagram of the force applied to the cover plate 330 in the folded state in section A of Figure 4. The protective layer 333 is not shown in Figure 8, and the hollow arrows in Figure 8 indicate the direction of the force applied.

[0110] In this example, the top of the cover plate 330 can withstand pressure loads and is not easily damaged, and has high impact resistance. The cover plate 330 is folded inward, and when in the folded state, one side of the first surface 131 of the substrate layer 10 is subjected to compressive stress, and one side of the second surface 133 is subjected to tensile stress. By utilizing the first opening 151 and the second opening 153 and the adhesive layer 30 and the elastic material layer 50 filled in the first opening 151 and the second opening 153, the elastic material layer 50 can fully withstand the stress risk and can fully release the stress concentration problem caused by bending of the cover plate 330. It is understandable that the cover plate 330 can also be folded outward. In this case, one side of the first surface 131 of the substrate layer 10 is subjected to tensile stress, and one side of the second surface 133 is subjected to compressive stress.

[0111] In a room-temperature dynamic bending test, experimental testing showed that the cover plate 330 structure, which only had the first opening 151 and the second opening 153 but was not filled with the adhesive layer 30 and the elastic material layer 50, could bend nearly 200,000 times. However, the cover plate 330 provided in this example, by filling the first opening 151 and the second opening 153 with the adhesive layer 30 and the elastic material layer 50, can bend over 300,000 times while maintaining high impact resistance. The cover plate 330 can be folded both inwardly and outwardly simultaneously, without being restricted by the bending direction of the cover plate 330.

[0112] In the cover plate 330 provided in the first example, by providing an opening 15 at the bendable portion 13 of the substrate layer 10 and filling the opening 15 with an elastic material layer 50, the stress at the bendable portion 13 of the substrate layer 10 can be fully released, thereby resolving the stress concentration problem caused by bending in the bendable portion 13. This allows the cover plate 330 to achieve a target bending radius when bending, while also facilitating an increase in the number of bends of the cover plate 330, resulting in excellent bending capabilities. This reduces the risk of creases or cracks in the cover plate 330 caused by bending, thereby helping to alleviate issues such as peeling and display failures of the display module 300, as well as leakage and bubbles in the display module 300. Furthermore, the filled elastic material layer 50 can fully withstand stress risks, giving the cover plate 330 high impact resistance.

[0113] In addition, by providing an adhesive layer 30 on the hole wall surface of the opening 15 and connecting the elastic material layer 50 to the adhesive layer 30, on the one hand, the adhesive layer 30 can fix the elastic material layer 50 to prevent the elastic material layer 50 from detaching from the opening 15; on the other hand, the adhesive layer 30 can bear part of the stress, which is beneficial to enhancing the bending resistance of the cover plate 330; on the other hand, the adhesive layer 30 can bond the elastic material layer 50 to the hole wall surface of the opening 15, which can avoid the formation of gaps between the elastic material layer 50 and the hole wall surface of the opening 15, thereby avoiding the formation of bubbles in the cover plate 330, and avoiding the generation of interference fringes or moiré patterns when light passes through the bubbles, which is beneficial to improving the appearance and light transmission effect of the cover plate 330.

[0114] Furthermore, the protective layer 333 in the cover plate 330 protects the substrate layer 10 and improves the vertical impact strength of the cover plate 330. This addresses issues such as the increased risk of process fragmentation, edge collapse, and low production yields caused by the thin thickness of the substrate layer 10. By further limiting the film hardness of the protective layer 333, the high impact resistance of the cover plate 330 can be further enhanced.

[0115] Please refer to FIG9 , which is a schematic cross-sectional view of a partial structure of the cover plate 330 in the second example.

[0116] The cover plate 330 of the second example is different from the cover plate 330 of the first example in that the filling layer 350 in the bendable cover plate portion 330 b of the cover plate 330 of the second example further includes a first supporting portion 70 , which is disposed in the opening 15 .

[0117] Specifically, the filling layer 350 in the flexible cover portion 330b of the cover 330 of the second example includes an adhesive layer 30, an elastic material layer 50, and a first support portion 70. Taking the first support portion 70 disposed within the first opening 151 as an example, the first support portion 70 is connected to the surface of the bottom wall of the first opening 151 and extends in a direction away from the bottom wall of the first opening 151. The elastic material layer 50 is disposed around the first support portion 70 and covers the circumference of the first support portion 70. The term "connection" includes direct and indirect connection. In this example, the first support portion 70 is disposed on the portion of the adhesive layer 30 located on the bottom wall of the opening 15 and on the side of the adhesive layer 30 facing away from the bottom wall of the first opening 151, thereby indirectly connecting the first support portion 70 to the bottom wall of the first opening 151. It is understood that in other examples, the first support portion 70 may also be directly fixedly connected to the bottom wall of the first opening 151. In this example, the elastic material layer 50 fills the gap between the adhesive layer 30 and the first supporting portion 70 .

[0118] In this example, there are multiple first support portions 70, and the multiple first support portions 70 are spaced apart from each other. In this example, each first support portion 70 extends from the bottom wall of the first opening 151 toward the opening of the first opening 151. The surface of each first support portion 70 facing away from the bottom wall of the first opening 151 is flush with the opening of the first opening 151, which helps to improve the surface flatness of the cover plate 330. In other examples, the surface of the first support portion 70 facing away from the bottom wall of the first opening 151 can also be lower than the opening of the first opening 151, and the surface of the elastic material layer 50 facing away from the bottom wall of the first opening 151 is flush with the opening of the first opening 151 through the filling of the elastic material layer 50.

[0119] The elastic modulus of the first support portion 70 is greater than the elastic modulus of the elastic material layer 50. Exemplarily, the elastic modulus of the first support portion 70 is greater than or equal to 500 MPa. Exemplarily, the material of the first support portion 70 includes, but is not limited to, PMMA (Polymethyl Methacrylate), PS (Polystyrene), and NAS (acrylic (PMMA) copolymer). Exemplarily, the width or diameter of the first support portion 70 is 0.5 μm to 2 μm, and the extension length of the first support portion 70 is less than or equal to the depth D1 of the first opening 151.

[0120] The arrangement of the first support portion 70 in the second opening 153 is similar to that in the first opening 151 , and reference may be made to the arrangement of the first support portion 70 in the first opening 151 , which will not be repeated here.

[0121] Compared with the cover plate 330 of the first example, in the cover plate 330 provided in the second example, a first support portion 70 extending away from the bottom wall of the hole 15 is added in the opening 15. The first support portion 70 can support and withstand the vertical stress exerted on the cover plate 330, thereby further enhancing the vertical high impact resistance function of the cover plate 330.

[0122] Referring to Figures 10 and 11, Figure 10 is a partial flow chart of the preparation of the cover plate 330 of the second example shown in Figure 9, and Figure 11 is a flow chart of another portion of the preparation of the cover plate 330 of the second example shown in Figure 9. Figures 10 and 11 illustrate only the preparation of the first opening 151 and the filling layer 350 filled in the first opening 151. The preparation of the second opening 153 and the filling layer 350 filled in the second opening 153 on the other side can be referred to the preparation of the first opening 151 and the filling layer 350 filled in the first opening 151, and will not be repeated here.

[0123] This example also provides a method for preparing the cover plate 330, including:

[0124] S1. Take a substrate layer 10, prepare a first photoresist layer 81 on the surface of the substrate layer 10, take a first mask plate 82 and place it on the side of the first photoresist layer 81 facing away from the substrate layer 10, and expose the first photoresist layer 81 by irradiating light through the first mask plate 82. In this example, the first mask plate 82 includes a first light-transmitting portion 82a and a first non-light-transmitting portion 82b. Light is applied to the side of the first mask plate 82 facing away from the first photoresist layer 81 to expose the first photoresist layer 81. In this example, the first light-transmitting portion 82a is a light-transmitting hole, which penetrates the first mask plate 82 along the thickness direction of the first mask plate 82. The applied light is ultraviolet light (UV), and the material of the first photoresist layer 81 is a positive photoresist.

[0125] S2. Develop the exposed first photoresist layer 81 to expose a portion of the surface of the substrate layer 10. In this example, the surface of the substrate layer 10 opposite to the first light-transmitting portion 82a is exposed.

[0126] S3, etching the surface of the exposed substrate layer 10 to form a first opening 151. In this example, the substrate layer 10 is wet-etched using an HF solution.

[0127] S31. A second photoresist layer 83 is formed on the wall surface of the first opening 151. A first mask plate 82 is placed on the side of the second photoresist layer 83 facing away from the substrate layer 10. Light is then irradiated through the first mask plate 82 to expose the second photoresist layer 83. In this example, light is applied to the side of the first mask plate 82 facing away from the second photoresist layer 83 to expose the second photoresist layer 83.

[0128] S32: Remove the exposed second photoresist layer 83, exposing the first opening 151. In this example, a solvent is used to dissolve the exposed second photoresist layer 83 to remove the exposed second photoresist layer 83. The material of the second photoresist layer 83 is different from that of the first photoresist layer 81. When the solvent is used to dissolve and remove the exposed second photoresist layer 83, the developed first photoresist layer 81 is retained.

[0129] S4. An adhesive layer 30 is disposed on the wall surface of the first opening 151, and the developed first photoresist layer 81 is removed. In this example, when the adhesive layer 30 is disposed, it may adhere to the wall surface of the first opening 151 and the surface of the retained first photoresist layer 81. By removing the first photoresist layer 81, the adhesive layer 30 is adhered only to the wall surface of the first opening 151.

[0130] S411. A third photoresist layer 84 is formed on the side of the adhesive layer 30 facing away from the wall surface of the first opening 151. A second mask 85 is placed on the side of the third photoresist layer 84 facing away from the bottom wall of the first opening 151. Light is then shone through the second mask 85 to expose the third photoresist layer 84. In this example, the second mask 85 includes a second light-transmitting portion 85a and a second light-impermeable portion 85b. Light is applied to the side of the second mask 85 facing away from the third photoresist layer 84 to expose the third photoresist layer 84.

[0131] S412: Develop the exposed third photoresist layer 84 to form a first hole in the third photoresist layer 84, and fill the first hole with the material of the first support portion 70. In this example, the portion of the third photoresist layer 84 that is adjacent to the second light-transmitting portion 85a is removed to form the first hole.

[0132] S413 , removing the developed third photoresist layer 84 .

[0133] S5. Dispose an elastic material layer 50 on the side of the adhesive layer 30 facing away from the wall surface of the first opening 151. In this example, the elastic material layer 50 is filled into the gap between the first support portion 70 and the adhesive layer 30, so that the elastic material layer 50 is disposed on the side of the adhesive layer 30 facing away from the wall surface of the first opening 151. In this example, in step S5, the surface of the elastic material layer 50 facing away from the bottom wall of the first opening 151 is substantially flush with the opening of the first opening 151.

[0134] S6 , a protective layer 333 is then disposed on the surface of the base material layer 10 . The protective layer 333 covers the opening of the first opening 151 , thereby preparing a cover plate 330 .

[0135] In the above steps S31 and S32, the steps of providing the second photoresist layer 83, exposing the second photoresist layer 83, and removing the exposed second photoresist layer 83 can improve the production yield of the first opening 151, thereby improving the production yield of the cover plate 330. In other examples, steps S31 and S32 can be omitted.

[0136] 12 and 13 , FIG12 is a schematic cross-sectional view of a partial structure of the cover plate 330 in the third example, and FIG13 is a schematic view of the force applied to portion B of the structure shown in FIG12 when subjected to an extrusion force.

[0137] The cover plate 330 of the third example is different from the cover plate 330 of the first example in that the filling layer 350 in the bendable cover plate portion 330 b of the cover plate 330 of the third example further includes a second supporting portion 90 , which is disposed in the opening 15 .

[0138] Specifically, the filling layer 350 in the bendable cover portion 330b of the cover 330 of the third example includes an adhesive layer 30, an elastic material layer 50, and a second support portion 90. Taking the second support portion 90 disposed within the first opening 151 as an example, the second support portion 90 is connected to the surface of the sidewall of the first opening 151 and extends in a direction away from the sidewall of the first opening 151. The elastic material layer 50 is disposed around the second support portion 90 and covers the circumference of the second support portion 90. The term "connection" includes direct and indirect connection. In this example, the first support portion 70 is disposed in the portion of the adhesive layer 30 located on the sidewall of the first opening 151, and is located on the side of the adhesive layer 30 facing away from the sidewall of the first opening 151, thereby indirectly connecting the second support portion 90 to the sidewall of the first opening 151. It is understood that in other examples, the second support portion 90 may also be directly fixedly connected to the sidewall of the first opening 151. In this example, the elastic material layer 50 fills the gap between the adhesive layer 30 and the second supporting portion 90 .

[0139] In this example, there are multiple second support parts 90, and the multiple second support parts 90 are spaced apart from each other. In this example, each second support part 90 extends in the direction away from the side wall of the first opening 151. In this embodiment, the extension length of each second support part 90 is less than the width of the first opening 151 at the depth at which the second support part 90 is set. The surface of the bottom wall of each second support part 90 away from the first opening 151 is lower than the opening of the first opening 151. At this time, the surface of the bottom wall of the elastic material layer 50 away from the first opening 151 can be flush with the opening of the first opening 151 through the filled elastic material layer 50, which is conducive to improving the surface flatness of the cover plate 330. In other examples, the surface of the bottom wall of the hole of some second support parts 90 away from the first opening 151 can also be flush with the opening of the first opening 151.

[0140] The elastic modulus of the second support portion 90 is greater than the elastic modulus of the elastic material layer 50. Exemplarily, the elastic modulus of the second support portion 90 is greater than or equal to 500 MPa. Exemplarily, the material of the second support portion 90 includes, but is not limited to, PMMA (Polymethyl Methacrylate), PS (Polystyrene), and NAS (Acrylic (PMMA) copolymer).

[0141] In this example, each second support portion 90 includes a first support portion 91 and a second support portion 93. The first support portion 91 and the second support portion 93 are both connected to the sidewall of the first opening 151. The first support portion 91 and the second support portion 93 are spaced apart and arranged opposite to each other. Specifically, the end surface of the first support portion 91 facing away from the sidewall of the first opening 151 and the end surface of the second support portion 93 facing away from the sidewall of the first opening 151 are opposite to each other and spaced apart.

[0142] The second support portion 90 is disposed in the second opening 153 in a manner similar to that in the first opening 151 , and may be disposed in the first opening 151 with reference thereto, which will not be further described here.

[0143] Compared to the cover plate 330 of the first example, the cover plate 330 provided in the third example incorporates a second support portion 90 extending away from the sidewall of the opening 15 within the opening 15. This second support portion 90 is capable of supporting and withstanding lateral stresses applied to the cover plate 330, further enhancing the high lateral impact resistance of the cover plate 330. As shown in FIG13 , when the cover plate 330 is folded, the first support portion 91 and the second support portion 93 of each second support portion 90 can abut against each other, enabling the second support portion 90 to support and withstand the horizontal lateral stress applied to the cover plate 330, further enhancing the high lateral bending resistance of the cover plate 330.

[0144] Referring to Figures 12 and 14 , Figure 14 is a partial flow chart for preparing the cover plate 330 shown in Figure 12 . Figure 14 only illustrates the preparation of the second support portion 90 within the first opening 151 . The preparation method for the second support portion 90 within the second opening 153 can be similar to the preparation method for the second support portion 90 within the first opening 151 and will not be further described here.

[0145] When preparing the cover plate 330 of the third example, steps S1 to S6 are the same as steps S1 to S4 of the preparation process of the cover plate 330 of the second example. The other steps are shown in FIG14 :

[0146] S5. Prepare an elastic material layer 50 on the side of the adhesive layer 30 away from the bottom wall of the first opening 151. In this example, in step S5, the surface of the elastic material layer 50 away from the bottom wall of the first opening 151 is lower than the opening of the first opening 151.

[0147] S51. Set a fourth photoresist layer on the side of the elastic material layer 50 away from the bottom wall of the first opening 151, take a third mask and place it on the side of the fourth photoresist layer away from the bottom wall of the first opening 151, and use light to pass through the third mask to expose the fourth photoresist layer.

[0148] S52: Develop the exposed fourth photoresist layer to form a second hole in the fourth photoresist layer, and fill the second hole with the material of the second support portion 90. In this example, there are multiple second holes, each of which includes a first hole portion and a second hole portion. The material of the second support portion 90 filled in the first hole portion forms the first support portion 91 of the second support portion 90, and the material of the second support portion 90 filled in the second hole portion forms the second support portion 93 of the second support portion 90.

[0149] S53 , removing the developed fourth photoresist layer.

[0150] S54, repeating steps S5, S51, S52 and S53 in sequence. In step S54 of this example, the elastic material layer 50 is repeatedly filled between the first supporting portion 91 and the second supporting portion 93, and the first supporting portion 91 and the second supporting portion 93 of the second supporting portion 90 are repeatedly prepared.

[0151] S6 , a protective layer 333 is then disposed on the surface of the base material layer 10 . The protective layer 333 covers the opening of the first opening 151 , thereby preparing a cover plate 330 .

[0152] Please refer to Fig. 15, which is a schematic top view of the cover plate 330 in the fourth embodiment. The protective layer 333 is not shown in Fig. 15.

[0153] The cover plate 330 of the fourth example is different from the cover plate 330 of the first example in that the filling layer 350 in the bendable cover plate portion 330 b of the cover plate 330 of the fourth example includes both a first support portion 70 and a second support portion 90 .

[0154] Specifically, the filling layer 350 in the bendable cover portion 330b of the cover plate 330 of the fourth example includes an adhesive layer 30, an elastic material layer 50, a first support portion 70, and a second support portion 90. Taking the example of the first support portion 70 and the second support portion 90 both being disposed within the first opening 151, the first support portion 70 is connected to the bottom wall of the first opening 151, the second support portion 90 is connected to the side wall of the first opening 151, and the second support portion 90 is spaced apart from the first support portion 70. The elastic material layer 50 is disposed around the first support portion 70 and the second support portion 90, and covers the circumference of the first support portion 70 and the circumference of the second support portion 90. The structure, fixing position, and preparation process of the first support portion 70 and the second support portion 90 refer to the second and third examples above, respectively.

[0155] The arrangement of the first support portion 70 and the second support portion 90 in the second opening 153 is similar to that in the first opening 151 , and the arrangement of the first support portion 70 and the second support portion 90 in the first opening 151 may refer to the arrangement of the first support portion 70 and the second support portion 90 in the first opening 151 , which will not be repeated here.

[0156] Compared with the cover plate 330 of the first example, the cover plate 330 provided in the fourth example, by simultaneously adding a first support portion 70 and a second support portion 90, uses the first support portion 70 to support and withstand the vertical stress received by the cover plate 330, and uses the second support portion 90 to support and withstand the horizontal lateral stress received by the cover plate 330, which is beneficial for simultaneously improving the vertical high impact resistance function and the lateral high bending resistance performance of the cover plate 330.

[0157] Referring to Figures 16, 17, and 18, Figure 16 is a schematic cross-sectional view of the cover plate 330 in the fifth embodiment, Figure 17 is a schematic top view of the cover plate 330 shown in Figure 16 with the filling layer 350 filling the opening 15, and Figure 18 is a schematic exploded perspective view of the cover plate 330 shown in Figure 16. The adhesive layer 30 and the elastic material layer 50 are not shown in Figure 18.

[0158] The cover plate 330 of the fifth example is different from the cover plate 330 of the first example in that the filling layer 350 in the bendable cover plate portion 330 b of the cover plate 330 of the fifth example further includes a reinforcement portion 20 .

[0159] Specifically, the filling layer 350 in the bendable cover plate portion 330b of the cover plate 330 of the fifth example includes a reinforcement portion 20, an adhesive layer 30 and an elastic material layer 50. Taking the reinforcement portion 20 provided in the first opening 151 as an example, in this example, the shape of the first opening 151 is cylindrical. In this example, there are multiple reinforcement portions 20, each of which is connected to the bottom wall of each first opening 151 in the substrate layer 10 and extends in a direction away from the bottom wall of the first opening 151. Here, "connection" includes direct connection and indirect connection. In this example, each reinforcement portion 20 is directly fixedly connected to the bottom wall of a first opening 151, that is, first, the reinforcement portion 20 is provided on the bottom wall of the first opening 151, and then the material of the adhesive layer 30 is filled between the hole wall surface of the first opening 151 and the reinforcement portion 20. For example, a photoresist may be coated in the first opening 151, and the photoresist may be exposed and developed using a mask to form a hole having the same shape as the reinforcing portion 20 in the first opening 151. The hole is then filled with the material of the reinforcing portion 20, and the photoresist is finally removed to grow the reinforcing portion 20 in the first opening 151. For example, the opening 15 and the filling hole 371 may be etched in the substrate layer 10 to form the reinforcing portion 20 in the opening 15. It is understood that in other examples, the material of the adhesive layer 30 may be adhered to the bottom wall of the opening 15, and the reinforcing portion 20 may be provided on the side of the adhesive layer 30 facing away from the bottom wall of the opening 15, so that the reinforcing portion 20 is adhered to the adhesive layer 30, thereby indirectly connecting the reinforcing portion 20 to the bottom wall of the opening 15.

[0160] The elastic modulus of the reinforcement portion 20 is greater than the elastic modulus of the elastic material layer 50. Exemplarily, the elastic modulus of the reinforcement portion 20 is greater than or equal to 500 MPa. Exemplary materials of the reinforcement portion 20 include, but are not limited to, ultra-thin glass (UTG), PMMA (Polymethyl Methacrylate), PS (Polystyrene), and NAS (acrylic (PMMA) copolymer).

[0161] Each reinforcement portion 20 is provided with a plurality of filling holes 371, which are spaced apart from each other. The opening of each filling hole 371 is located on the surface of the reinforcement portion 20 facing away from the bottom wall of the first opening 151, facilitating the filling of material into the filling holes 371 of the reinforcement portion 20 after the reinforcement portion 20 is secured. In this example, each filling hole 371 is cylindrical in shape. Referring to Figures 19 and 20, Figure 19 is a top view of a portion of the cover plate 330 in another example, showing the filling layer 350 filling the first opening 151. Figure 20 is a perspective exploded view of the portion of the cover plate 330 shown in Figure 19. The adhesive layer 30 and the elastic material layer 50 are not shown in Figure 20. In other examples, the shape of each filling hole 371 of the reinforcement portion 20 can also be a hexagonal prism, so that the reinforcement portion 20 presents a honeycomb structure. It can be understood that the filling hole 371 can also be other shapes, such as the top view shape of the filling hole 371 is polygonal, curved, irregular, etc. The present application does not limit the shape of the filling hole 371.

[0162] The adhesive layer 30 is bonded between the wall surface of the first opening 151 and the outer side of the reinforcement portion 20, so that the adhesive layer 30 surrounds the reinforcement portion 20 and at least partially covers the circumference of the reinforcement portion 20. The elastic material layer 50 is filled into the plurality of filling holes 371 of each reinforcement portion 20.

[0163] The manner in which the reinforcing portion 20 is disposed in the second opening 153 is similar to the manner in which it is disposed in the first opening 151 , and reference may be made to the manner in which the reinforcing portion 20 is disposed in the first opening 151 , which will not be repeated here.

[0164] Compared to the cover plate 330 of the first example, the cover plate 330 provided in the fifth example has a plurality of filling holes 371 provided in the reinforcement portion 20, so that the reinforcement portion 20 forms a mesh structure. By disposing the reinforcement portion 20 within the opening 15 and filling the filling holes 371 of the reinforcement portion 20 with the elastic material layer 50, the reinforcement portion 20 and the elastic material layer 50 form a highly resistant bending structure, thereby enabling the cover plate 330 to simultaneously achieve high lateral flexural resistance and high vertical impact resistance. In addition, by disposing the adhesive layer 30 surrounding the reinforcement portion 20 and covering the circumference of the reinforcement portion 20, so that the adhesive layer 30 is filled in the gap between the hole wall surface of the opening 15 and the reinforcement portion 20, the microcrack damage that may be generated during the formation of the reinforcement portion 20 with a mesh structure can be reduced, thereby further enhancing the high lateral flexural resistance and high vertical impact resistance of the cover plate 330.

[0165] Referring to Figures 21, 22, and 23, Figure 21 is a schematic cross-sectional view of the cover plate 330 in the sixth embodiment, Figure 22 is a schematic top view of the cover plate 330 shown in Figure 21, and Figure 23 is a schematic exploded perspective view of the cover plate 330 shown in Figure 21. The protective layer 333 is not shown in Figure 22, and the adhesive layer 30 and the elastic material layer 50 are not shown in Figure 23.

[0166] The difference between the cover plate 330 of the sixth example and the cover plate 330 of the fifth example is that the opening 15 of the substrate layer 10 in the bendable cover plate portion 330b of the cover plate 330 of the sixth example is different from the opening 15 of the substrate layer 10 in the bendable cover plate portion 330b of the cover plate 330 of the fifth example.

[0167] Specifically, taking the first opening 151 as an example, the first opening 151 penetrates one surface of the bendable portion 13 along the thickness direction and penetrates at least one side surface of the bendable portion 13 of the substrate layer 10 along the length direction. It is understood that in other examples, the first opening 151 may also penetrate one side surface of the bendable portion 13 of the substrate layer 10 along the length direction. In this example, the first opening 151 is in the shape of a rectangular parallelepiped. In this example, there is one first opening 151, and the width of the first opening 151 is equal to the width W of the bendable portion 13. The width of the second opening 153 is equal to the width W of the bendable portion 13. It is understood that the width of the first opening 151 may also be less than the width W of the bendable portion 13. The configuration of the second opening 153 is similar to that of the first opening 151. For details, please refer to the configuration of the first opening 151 and will not be repeated here.

[0168] In the sixth example, the cover plate 330 is provided with an opening 15 in the bendable portion 13 of the substrate layer 10 and a reinforcement 20 secured within the opening 15 using an adhesive layer 30. This effectively relieves stress in the bendable portion 13 of the substrate layer 10, addressing stress concentration caused by bending. Furthermore, the reinforcement 20 enhances the cover plate 330's high lateral bending resistance and high vertical impact resistance. Furthermore, the elastic material layer 50 filled within the filling hole 371 of the reinforcement 20 can fully withstand stress risks, further enhancing the cover plate 330's high impact resistance.

[0169] Please refer to FIG. 24 , which is a schematic diagram of the exploded three-dimensional structure of the cover plate 330 in the seventh example.

[0170] The cover plate 330 of the seventh example differs from the cover plate 330 of the sixth example in that the first opening 151 of the substrate layer 10 in the bendable cover plate portion 330b of the cover plate 330 of the seventh example penetrates the bendable portion 13 of the substrate layer 10 along the thickness direction.

[0171] Specifically, the first opening 151 penetrates the surface of the bendable portion 13 of the substrate layer 10 along the thickness direction of the bendable portion 13. The adhesive layer 30 is connected between the hole wall of the first opening 151 and the reinforcement portion 20, and the elastic material layer 50 is filled in the filling hole 371 of the reinforcement portion 20.

[0172] In the cover plate 330 provided in the seventh example, a first opening 151 is provided through the bendable portion 13, and the reinforcement portion 20 is bonded to the wall of the first opening 151 using an adhesive layer 30, thereby achieving splicing of the reinforcement portion 20 between the first portion 11 and the second portion 12. Furthermore, by filling the filling hole 371 of the reinforcement portion 20 with an elastic material layer 50, the cover plate 330 further enhances its high lateral bending resistance and high vertical impact resistance.

[0173] Referring to Figures 25 and 26 , Figure 25 is a schematic diagram of the structure of the foldable electronic device 1000 provided in the second embodiment of the present application when in a folded state, and Figure 26 is a schematic diagram of the forces acting on various parts of the display module 300 of the foldable electronic device 1000 shown in Figure 25 when bent. Figure 26 (a) shows a schematic diagram of the forces acting on the first bendable portion 302 of the display module 300, and Figure 26 (b) shows a schematic diagram of the forces acting on the second bendable portion 304.

[0174] The foldable electronic device 1000 of the second embodiment is different from the foldable electronic device 1000 of the first embodiment in that the foldable electronic device 1000 of the second embodiment can be folded twice.

[0175] Specifically, the housing 100 of the foldable electronic device 1000 of the second embodiment includes a first housing 110, a first rotating shaft (not shown in Figures 25 and 26), a second housing 130, a second rotating shaft (not shown in Figures 25 and 26), a third housing 150, and a shaft cover 170. The first rotating shaft is rotatably connected between the first housing 110 and the second housing 130, the second rotating shaft is rotatably connected between the second housing 130 and the third housing 150, and the shaft cover 170 is mounted on the outside of the second rotating shaft. The first housing 110 is foldable relative to the second housing 130, and the third housing 150 is foldable relative to the second housing 130.

[0176] The display module 300 includes a first display portion 301, a first bendable portion 302, a second display portion 303, a second bendable portion 304, and a third display portion 305. The first display portion 301 is mounted on the first housing 110, the first bendable portion 302 is mounted on the first hinge, the second display portion 303 is mounted on the second housing 130, the second bendable portion 304 is mounted on the second hinge, and the third display portion 305 is mounted on the third housing 150.

[0177] In this embodiment, when the foldable electronic device 1000 is in the folded state, the first display portion 301 is folded relative to the second display portion 303 and disposed opposite the second display portion 303. The first bendable portion 302 bends, and the side of the first bendable portion 302 facing the housing 100 is subjected to compressive stress, while the side facing away from the housing 100 is subjected to tensile stress. The third display portion 305 is folded relative to the second display portion 303 and disposed opposite the second display portion 303. The second bendable portion 304 bends, and the side of the second bendable portion 304 facing away from the housing 100 is subjected to compressive stress, while the side of the second bendable portion 304 facing the housing 100 is subjected to tensile stress.

[0178] The first bendable portion 302 and the second bendable portion 304 each include a portion of the display panel and a bendable cover portion of the cover. The bendable cover portion of the cover in the first bendable portion 302 and the bendable cover portion of the cover in the second bendable portion 304 are independently selected from the structures of the bendable cover portion 330b of the cover in the first to seventh examples.

[0179] The above disclosure is only a preferred embodiment of the present application, and it is certainly not intended to limit the scope of the rights of the present application. A person skilled in the art can understand that all or part of the processes of the above embodiments and equivalent changes made in accordance with the claims of the present application are still within the scope of the present application.

Claims

1. A cover plate, characterized in that, The cover plate includes a substrate layer, an adhesive layer and an elastic material layer, the substrate layer includes a first part, a second part and a bendable part, the bendable part is connected between the first part and the second part, the substrate layer is provided with a first opening, the opening of the first opening is provided on a surface of the bendable part along the thickness direction, the adhesive layer is bonded to the hole wall surface of the first opening, and the elastic material layer is connected to the side of the adhesive layer away from the hole wall surface of the first opening.

2. The cover plate according to claim 1, wherein The cover plate further includes a protective layer, which is disposed on the surface of the substrate layer and covers the opening of the first opening.

3. The cover plate according to claim 2, wherein, The paint film hardness of the protective layer is ≥3H.

4. The cover plate according to claim 1, characterized in that, The bendable portion includes a first surface and a second surface arranged opposite to each other in the thickness direction, the substrate layer also includes a second opening, the opening of the first opening is arranged on the first surface, the second opening is arranged on the second surface, the adhesive layer is also bonded to the hole wall surface of the second opening, and the elastic material layer is connected to the side of the adhesive layer away from the hole wall surface of the second opening.

5. The cover plate according to any one of claims 1 to 4, characterized in that, The cover plate also includes a first support portion, which is connected to the surface of the bottom wall of the first opening and extends in a direction away from the bottom wall of the first opening. The elastic material layer is arranged around the first support portion and covers the circumference of the first support portion.

6. The cover plate according to claim 5, characterized in that, The elastic modulus of the first supporting portion is greater than the elastic modulus of the elastic material layer.

7. The cover plate according to claim 5, characterized in that, A surface of the first supporting portion facing away from the bottom wall of the first opening is lower than the opening of the first opening, or a surface of the first supporting portion facing away from the bottom wall of the first opening is flush with the opening of the first opening.

8. The cover plate according to any one of claims 1 to 4, characterized in that, The cover plate also includes a second support portion, which is connected to the surface of the adhesive layer away from the side wall of the first opening and extends in a direction away from the side wall of the first opening. The elastic material layer is arranged around the second support portion and covers the circumference of the second support portion.

9. The cover plate according to claim 8, characterized in that, The elastic modulus of the second supporting portion is greater than the elastic modulus of the elastic material layer.

10. The cover plate according to claim 8, characterized in that The second supporting portion includes a first supporting portion and a second supporting portion, wherein the first supporting portion and the second supporting portion are both connected to the hole side wall of the first opening, and the first supporting portion and the second supporting portion are opposite to each other and spaced apart.

11. The cover plate according to claim 8, characterized in that, The surface of the second supporting portion facing away from the bottom wall of the first opening is lower than the opening of the first opening, or the surface of the second supporting portion facing away from the bottom wall of the first opening is flush with the opening of the first opening.

12. The cover plate according to any one of claims 1 to 4, characterized in that, There are a plurality of the first openings, and the plurality of the first openings are spaced apart from each other and arranged in an array.

13. The cover plate according to any one of claims 1 to 4, characterized in that, The elastic modulus of the elastic material layer is 3MPa-300MPa, and / or the elongation at break of the elastic material layer is greater than 120%.

14. The cover plate according to any one of claims 1 to 4, characterized in that, The elastic modulus of the bonding layer is greater than or equal to 80 MPa.

15. The cover plate according to any one of claims 1 to 4, characterized in that, The cover plate further includes a reinforcing portion, the reinforcing portion is disposed in the first opening, and is connected to a side of the bonding layer facing away from the hole wall surface of the first opening. The bonding layer is disposed around the reinforcing portion and at least partially covers the peripheral surface of the reinforcing portion. The reinforcing portion is provided with a filling hole, an opening of the filling hole is disposed on the surface of the reinforcing portion, and the elastic material layer is filled in the filling hole.

16. The cover plate according to claim 15, characterized in that, The first opening penetrates at least one side surface of the bendable portion along the length direction.

17. The cover plate according to claim 15, characterized in that, The first opening penetrates the bendable portion in the thickness direction.

18. The cover plate according to claim 15, characterized in that, The opening of the filling hole is disposed on the surface of the reinforcing portion facing the opening of the first opening.

19. The cover plate according to claim 15, characterized in that, The elastic modulus of the reinforcing portion is greater than the elastic modulus of the elastic material layer.

20. A display module, characterized in that, It includes a display panel and the cover plate according to any one of claims 1 to 19, and the cover plate is mounted on the display panel.

21. A foldable electronic device, characterized in that, It includes a housing and the display module according to claim 20, the display panel is mounted on the housing, and the cover plate is mounted on a side of the display panel facing away from the housing.

22. A method for preparing a cover plate, characterized in that, It includes: Take a substrate layer, prepare a first photoresist layer on the surface of the substrate layer, place a first mask on a side of the first photoresist layer facing away from the substrate layer, and expose the first photoresist layer by using light passing through the first mask; Develop the exposed first photoresist layer to expose a part of the surface of the substrate layer; Etch the exposed surface of the substrate layer to form a first opening; Set a bonding layer on the hole wall surface of the first opening, and remove the developed first photoresist layer; Set an elastic material layer on a side of the bonding layer facing away from the hole wall surface of the first opening.

23. The manufacturing method of the cover plate according to claim 22, characterized in that, Between the step of etching the exposed surface of the substrate layer to form a first opening and the step of setting a bonding layer on the hole wall surface of the first opening and removing the developed first photoresist layer, it further includes: setting a second photoresist layer on the hole wall surface of the first opening, placing the first mask on a side of the second photoresist layer facing away from the substrate layer, and exposing the second photoresist layer by using light passing through the first mask; Remove the exposed second photoresist layer to expose the first opening.

24. The preparation method according to claim 22 or 23, characterized in that, The cover plate further includes a first support portion. Between the step of setting a bonding layer on the hole wall surface of the first opening and removing the developed first photoresist layer and the step of setting an elastic material layer on a side of the bonding layer facing away from the hole wall surface of the first opening, it further includes the step of setting the first support portion in the first opening: Set a third photoresist layer on a side of the bonding layer facing away from the hole wall surface of the first opening, place a second mask on a side of the third photoresist layer facing away from the bottom wall of the first opening, and expose the third photoresist layer by using light passing through the second mask; Develop the exposed third photoresist layer to form a first hole in the third photoresist layer, and fill the material of the first support portion in the first hole; Remove the developed third photoresist layer.

25. The preparation method according to claim 22 or 23, characterized in that, The cover plate further includes a second supporting portion, and after the step of removing the second photoresist layer after exposure to expose the first opening, the step of arranging the second supporting portion in the first opening is further included: Disposing a fourth photoresist layer on a side of the elastic material layer away from the bottom wall of the first opening, placing a third mask on a side of the fourth photoresist layer away from the bottom wall of the first opening, and exposing the fourth photoresist layer by light through the third mask; Developing the exposed fourth photoresist layer to form a second hole in the fourth photoresist layer, and filling the second hole with the material of the second supporting part; The developed fourth photoresist layer is removed.

Images