Cover plate, display panel and electronic equipment

Abstract

This application discloses a cover plate, a display panel, and an electronic device. The display panel includes a screen body, a cover plate, a first adhesive layer, a support film, and a second adhesive layer. The cover plate is disposed on one side of the screen body, the first adhesive layer is disposed on the surface of the cover plate near the screen body, the support film is disposed on the side of the screen body away from the cover plate, and the second adhesive layer is disposed on the surface of the support film near the screen body. At least one of the cover plate and the support film is made of polyethylene terephthalate and / or polyethylene naphthalate, and the portion of its side edge located in the bending area is flush with the side edge of the screen body or extends beyond the side edge of the screen body by less than or equal to 0.1 mm. This provides the cover plate and support film with good bending performance while reducing the cost of the display panel.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a cover plate, display panel, and electronic device. Background Technology

[0002] With the development of AMOLED (Active Matrix Organic Light Emitting Diode) technology, display panels are shifting from rigid substrates to flexible substrates. This means the substrate of the display panel uses flexible materials, making the panel flexible enough to be folded and rolled. PI (Polyimide) is commonly used as the flexible substrate.

[0003] To enable the folding and rolling of display panels, the cover and support films also need to be made of flexible materials. Covers and support films are typically made of CPI (Colorless Polyimide). However, the high cost of CPI hinders efforts to reduce the overall cost of display panels. Summary of the Invention

[0004] This application provides a cover plate, a display panel, and electronic devices to reduce costs while achieving folding or rolling.

[0005] To address the aforementioned technical problems, the first technical solution provided in this application is as follows: A display panel is provided, including a bending area and a non-bending area; the display panel includes a screen body, a cover plate, a first adhesive layer, a support film, and a second adhesive layer; the cover plate is disposed on one side of the screen body; the first adhesive layer is disposed on the surface of the cover plate near the screen body; the support film is disposed on the side of the screen body away from the cover plate; the second adhesive layer is disposed on the surface of the support film near the screen body; wherein, the material of the cover plate and / or the support film includes polyethylene terephthalate and / or polyethylene naphthalate, and the portion of its side located in the bending area is flush with the side of the screen body or extends beyond the side of the screen body by less than or equal to 0.1 mm.

[0006] In one embodiment, the side of the cover plate located in the bending area is provided with at least one first groove;

[0007] And / or, the side of the support membrane located in the bending area is provided with at least one second groove.

[0008] Preferably, the orthographic projection of the first groove toward the screen body is at least partially located on the screen body; the orthographic projection of the second groove toward the screen body is at least partially located on the screen body.

[0009] In one embodiment, the cross-sectional shape of the first groove is an arc along a direction parallel to the screen body, and / or the cross-sectional shape of the second groove is an arc.

[0010] In one embodiment, the display panel includes a display area and a non-display area disposed at the edge of the display area, the bending area spanning the display area and the non-display area; a first groove is disposed on the cover plate corresponding to the non-display area of ​​the screen body, and the depth of the first groove is less than or equal to the width of the non-display area; and / or a second groove is disposed on the support film corresponding to the non-display area of ​​the screen body, and the depth of the second groove is less than or equal to the width of the non-display area.

[0011] In one embodiment, along the bending axis of the bending region, the crystallinity of the cover plate in the middle region of the bending region is less than the crystallinity of the cover plate in the edge region of the bending region, and / or the crystallinity of the support film in the middle region of the bending region is less than the crystallinity of the support film in the edge region of the bending region.

[0012] In one embodiment, the crystallinity of the cover plate gradually increases along the direction from the middle region of the cover plate to the edge region of the cover plate in the portion of the bend area.

[0013] And / or the portion of the support film located in the bending region, along the direction from the middle region of the support film to the edge region of the support film, the crystallinity of the support film gradually increases;

[0014] Preferably, the cover plate located in the bending area has the same crystallinity on both edge regions; and / or the support film located in the bending area has the same crystallinity on both edge regions.

[0015] In one embodiment, the device further includes a touch layer, a polarizer, and a metal support layer; the touch layer and the polarizer are sequentially disposed on the side of the screen body near the cover plate, and the metal support layer is disposed on the side of the support film away from the screen body.

[0016] To solve the above-mentioned technical problems, the second technical solution provided by this application is: to provide an electronic device, including a display panel as described in any of the above claims.

[0017] To solve the above-mentioned technical problems, the third technical solution provided in this application is: to provide a cover plate, including a bending area and a non-bending area, for protecting the screen body, wherein the material of the cover plate includes polyethylene terephthalate and / or polyethylene naphthalate, and the portion of its side located in the bending area is flush with the side of the screen body or extends beyond the side of the screen body by less than or equal to 0.1 mm.

[0018] In one embodiment, the side of the cover plate located in the bending area is provided with at least one first groove;

[0019] And / or, along the bending axis of the bending region, the crystallinity of the cover plate in the middle region of the bending region is less than the crystallinity of the cover plate in the edge region of the bending region.

[0020] The beneficial effects of this application are as follows: Unlike the prior art, this application discloses a cover plate, a display panel, and an electronic device. The display panel includes a screen body, a cover plate, a first adhesive layer, a support film, and a second adhesive layer. The cover plate is disposed on one side of the screen body, the first adhesive layer is disposed on the surface of the cover plate near the screen body, and the portion of the side of the first adhesive layer located in the bending area is flush with the side of the screen body. The support film is disposed on the side of the screen body away from the cover plate, and the second adhesive layer is disposed on the surface of the support film near the screen body, and the portion of the side of the second adhesive layer located in the bending area is flush with the side of the screen body. At least one of the cover plate and the support film is made of polyethylene terephthalate and / or polyethylene naphthalate, and the portion of its side located in the bending area is flush with the side of the screen body or extends beyond the side of the screen body by less than or equal to 0.1 mm. This allows the cover plate and the support film to have good bending performance while reducing the cost of the display panel. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the display panel provided in an embodiment of this application;

[0023] Figure 2 yes Figure 1 A top view of the display panel shown in the diagram;

[0024] Figure 3 These are experimental diagrams of the cover plate and screen provided in this application;

[0025] Figure 4 This is another experimental diagram of the cover plate and screen body provided in this application;

[0026] Figure 5 yes Figure 1 A top view of the cover plate of the display panel shown in the diagram;

[0027] Figure 6 This is a schematic diagram of another embodiment of the first groove on the cover plate;

[0028] Figure 7 yes Figure 1 The diagram shows a top view of the support film of the display panel. Detailed Implementation

[0029] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0030] In the following description, specific details such as particular system architectures, interfaces, and technologies are presented for illustrative purposes rather than for limiting purposes, in order to provide a thorough understanding of this application.

[0031] The terms "first," "second," and "third" in this application are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of the stated features. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movement of components in a specific posture (as shown in the figures). If the specific posture changes, the directional indications also change accordingly. The terms "comprising" and "having," and any variations thereof, in the embodiments of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or components inherent to these processes, methods, products, or devices.

[0032] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0033] The present application will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] Please see Figure 1 and Figure 2 , Figure 1 This is a schematic diagram of the structure of the display panel provided in an embodiment of this application. Figure 2 yes Figure 1 The diagram shows a top view of the display panel.

[0035] The display panel provided in this embodiment is bendable, and includes a bending area A and a non-bending area B. The display panel is bent along the bending area A. The display panel includes a display area AA and a non-display area NA located at the edge of the display area AA. The bending area A spans the display area AA and the non-display area NA.

[0036] The display panel includes a screen body 11, a cover plate 12, a first adhesive layer 13, a support film 14, and a second adhesive layer 15. The screen body 11 includes a flexible substrate (not shown) and a display layer (not shown). The material selection and function of the flexible substrate are the same as in the prior art, and the specific arrangement and function of the display layer are also the same as in the prior art, and will not be repeated here. The cover plate 12 protects the screen body 11 and is located on one side of the screen body 11. The first adhesive layer 13 is provided on the surface of the cover plate 12 near the screen body 11 to achieve relative fixation between the cover plate 12 and the screen body 11. The support film 14 supports the screen body 11 and is located on the side of the screen body 11 away from the cover plate 12. The second adhesive layer 15 is provided on the surface of the support film 14 near the screen body 11 to achieve relative fixation between the support film 14 and the screen body 11. The side of the first adhesive layer 13 located in the bending area A is flush with the side of the screen body 11 and / or the cover plate 12, and the side of the second adhesive layer 15 located in the bending area A is flush with the side of the screen body 11 and / or the support film 14.

[0037] The materials of the cover plate 12 and / or the support film 14 include polyethylene terephthalate (PET) and / or polyethylene naphthalate (PEN). PET is a linear thermoplastic polymer with a high heat capacity melting temperature and glass transition temperature. It maintains excellent physical and mechanical properties such as fatigue resistance, abrasion resistance, aging resistance, and electrical insulation over a wide temperature range. It is stable to most organic solvents and inorganic acids, and its production has low energy consumption and good processability. According to the performance parameters of PET and PEN in Table 1, PEN has some superior properties compared to PET. The chemical structure of PEN is similar to that of PET, but the difference lies in the fact that PEN's molecular chain is composed of a more rigid naphthalene ring instead of the benzene ring in PET. The naphthalene ring structure gives PEN higher physical and mechanical properties, gas barrier properties, chemical stability, and heat resistance, UV resistance, and radiation resistance than PET. The good properties of PET and / or PEN can provide excellent protection for the screen 11 as the cover plate 12, and can also provide excellent support for the screen 11 as the support film 14. Furthermore, PET and / or PEN are transparent, with low refractive index and high transmittance, meeting the requirements for use as cover plate 12. PET and / or PEN are also flexible, allowing them to bend along with the screen 11. In the prior art, cover plate 12 and support film 14 are generally made of CPI or UTG (Ultra Thin Glass). Compared to CPI and UTG, PET and PEN are less expensive; therefore, using PET and / or PEN as the materials for cover plate 12 and / or support film 14 helps reduce the cost of the display panel.

[0038] Table 1 Performance of PET and PEN

[0039] Material PEN PET Melting point (°C) 265 260 Crystallization temperature (°C) 190 129 Heat resistance (°C) 175 120 Heat shrinkage rate (150℃, 30min, %) 0.4 1 Hydrolysis resistance (h) 200 50 Radiation resistance (MGY) 11 2 <![CDATA[Young's modulus (kg / mm 2 )]]> 1800 1200 Tensile modulus (MPa) 588 44 Impact resistance (mm) 2.24 2.18 Glass transition temperature (°C) 121 78 <![CDATA[Tensile strength (kg / mm 2 )]]> 50 45

[0040] Because the rigid conjugated structure in the PET molecular chain hinders the movement of molecular chain segments and reduces their activity, PET suffers from drawbacks during processing, such as slow crystallization rate, long molding cycle, and poor impact strength of finished products. Furthermore, as shown in Table 2, the elastic modulus of PET is lower than that of CPI, and the deformation of PET is greater than that of CPI, meaning PET is more prone to deformation than CPI. However, the yield strength of CPI is 120 MPa (room temperature), while that of PET is 70 MPa (room temperature), indicating that PET's resistance to plastic deformation is weaker than that of CPI. PET is highly susceptible to plastic deformation under prolonged bending. PET's glass transition temperature is between 70℃ and 80℃, making it unable to withstand high temperatures. Moreover, as the temperature increases, the yield strength of PET decreases; for example, the yield strength of PET at 80℃ drops to 40 MPa, weakening its resistance to plastic deformation. In high-temperature environments, it is prone to edge shrinkage and deformation, leading to voids and gaps between film layers, resulting in poor bending performance and affecting the bending performance of display panels. PEN has a glass transition temperature below 122°C and cannot withstand high temperatures, exhibiting a similar disadvantage to PET.

[0041] Table 2 Performance of PET and CPI

[0042] Material PET CPI Elastic modulus (GPa) 2.7 4 Deformation 20.37 29

[0043] It is understood that display panels need to undergo bending tests at room temperature and under high temperature and humidity conditions to ensure the stability of their folding performance. Therefore, the cover plate 12 and / or support film 14 of the display panel need to meet the bending performance requirements of multiple environments (i.e., room temperature and high temperature and humidity conditions). However, PET and / or PEN are prone to deformation under high temperature and humidity conditions. When the cover plate 12 and / or support film 14 are made of PET and / or PEN materials with the existing structure, they cannot meet the bending performance requirements of multiple environments. In view of this, this application improves the structure of the cover plate 12 and / or support film 14 to meet the bending performance requirements of multiple environments; specifically, the portion of the side of the cover plate 12 located in the bending area A is flush with the side of the screen body 11 or extends beyond the side of the screen body 11 by less than or equal to 0.1 mm; and / or, the portion of the side of the support film 14 located in the bending area A is flush with the side of the screen body 11 or extends beyond the side of the screen body 11 by less than or equal to 0.1 mm.

[0044] It should be noted that in the prior art, the side of the cover plate 12 located in the bending area A extends beyond the side of the screen body 11 by 0.2mm-0.3mm. In this application, although the extension of the side of the cover plate 12 beyond the side of the screen body 11 is reduced, the cover plate 12 can still effectively protect the screen body 11 and will not affect the performance of the display panel.

[0045] By ensuring that the portion of the cover plate 12 located in the bending zone A is flush with or extends beyond the side of the screen body 11 by less than or equal to 0.1 mm, the stress on the portion of the first adhesive layer 13 located in the bending zone A is reduced, eliminating the extrusion phenomenon of the first adhesive layer 13 located in the bending zone A. The extrusion phenomenon of the first adhesive layer 13 is a contributing factor to wrinkles appearing when the cover plate 12 bends. By eliminating the extrusion phenomenon of the first adhesive layer 13 located in the bending zone A, wrinkles are avoided at the edge of the cover plate 12 located in the bending zone A when the cover plate 12 bends with the screen body 11, and deformation of the cover plate 12 is avoided. This, in turn, prevents holes and gaps between the display panel film layers, giving the cover plate 12 better bending performance in various environments. The support film 14, with the same technical effect, will not be described further.

[0046] This application conducted an experiment on the portion of the side of the cover plate 12 located in the bending area A that extends beyond the side of the screen body 11, as detailed below:

[0047] Please see Figure 3 and Figure 4 , Figure 3 These are experimental diagrams of the cover plate and screen body provided in this application. Figure 4 This is another experimental diagram of the cover plate and screen provided in this application.

[0048] It should be noted that, Figure 3 The portion of the side of the cover plate 12 shown in the bending area A extends beyond the side of the screen body 11 by more than 0.1 mm, for example, 0.2 mm; Figure 3 The stress in the circled area is relatively greater than that in other areas, which affects the shape of the first adhesive layer 13 located in this area and causes extrusion. Figure 4 The portion of the side of the cover plate 12 shown in the bending area A extends beyond the side of the screen body 11 by less than or equal to 0.1 mm, for example, 0.1 mm; Figure 4 The middle corresponds to Figure 3 No significant stress change was observed at the center circle position. In other words, by reducing the extent to which the side of the cover plate 12 extends beyond the side of the screen body 11 in the bending area A, the extrusion of the first adhesive layer 13 in the bending area A can be eliminated. When the side of the cover plate 12 in the bending area A does not extend beyond the side of the screen body 11, it must be flush with the side of the screen body 11 to provide protection for the screen body 11, which also eliminates the extrusion of the first adhesive layer 13 in the bending area A.

[0049] Optionally, the portions of the two opposite sides of the cover plate 12 located in the bending area A are flush with the sides of the screen body 11.

[0050] Optionally, the portion of the two opposite sides of the cover plate 12 located in the bending area A that extends beyond the side of the screen body 11 by a dimension of less than or equal to 0.1 mm.

[0051] Optionally, the portions of the two opposite sides of the support film 14 located in the bending area A are flush with the sides of the screen body 11.

[0052] Optionally, the portion of the two opposite sides of the support film 14 located in the bending area A that extends beyond the side of the screen body 11 is less than or equal to 0.1 mm.

[0053] Optionally, the first adhesive layer 13 is a transparent optical adhesive. The first adhesive layer 13 includes, but is not limited to, acrylic and methacrylic materials. In addition to having a light transmittance of ≥95%, these materials also have good bonding strength and a storage modulus of E-2Gpa to E-4Gpa.

[0054] Optionally, the thickness of the first adhesive layer 13 ranges from 15 μm to 200 μm.

[0055] Optionally, the second adhesive layer 15 is a transparent optical adhesive. The second adhesive layer 15 includes, but is not limited to, acrylic and methacrylic materials. In addition to having a light transmittance of ≥95%, these materials also have good bonding strength and a storage modulus of E-2Gpa to E-4Gpa.

[0056] Optionally, the thickness of the second adhesive layer 15 ranges from 15 μm to 200 μm.

[0057] Optionally, the light transmittance of the cover plate 12 is ≥95%, and the thickness of the cover plate 12 is in the range of 20μm to 100μm.

[0058] Please see Figure 5 , Figure 5 yes Figure 1 The diagram shows a top view of the cover plate of the display panel.

[0059] In this embodiment, the side of the cover plate 12 located in the bending area A is provided with at least one first groove 121. The orthogonal projection of the first groove 121 toward the screen body 11 is at least partially located on the screen body 11. That is, the side of the cover plate 12 located in the bending area A is recessed relative to the side of the screen body 11. This allows the long-range thermal shrinkage of the entire side of the cover plate 12 to be converted into short-range thermal shrinkage of the side of the cover plate 12 located in the bending area A when the cover plate 12 deforms under high temperature and high humidity conditions. This reduces the long-range adhesive stress of the first adhesive layer 13 along the entire side of the cover plate 12, which helps to eliminate the extrusion phenomenon of the first adhesive layer 13 located in the bending area A and avoids wrinkles at the edge of the cover plate 12 located in the bending area A. At the same time, by providing the first groove 121, deformation space is provided for the cover plate 12 during bending, further preventing wrinkles at the edge of the cover plate 12 located in the bending area A during bending, which helps to improve the bending performance of the display panel.

[0060] When the side of the first adhesive layer 13 is flush with the side of the screen body 11 and / or the cover plate 12 in the bending area A, and the side of the cover plate 12 in the bending area A is provided with a first groove 121, part of the first adhesive layer 13 will be exposed. The size of the exposed first adhesive layer 13 is very small, and there will be no overflow of adhesive, clumps of adhesive, dust or other phenomena, which will not affect the product.

[0061] A first groove 121 is provided on the cover plate 12 corresponding to the non-display area NA of the screen 11, and the depth of the first groove 121 is less than or equal to the width of the non-display area NA. It is understood that the non-display area NA typically contains circuitry, which is covered by ink, and the depth of the first groove 121 is less than or equal to the width of the ink. The width of the ink is 0.3mm-2mm.

[0062] In one embodiment, the cross-sectional shape of the first groove 121 along the direction parallel to the screen body 11 is an arc. By setting the cross-sectional shape of the first groove 121 to an arc, the arc is subjected to more uniform force compared to other shapes, which can avoid the generation of local cracks under pressure during the bending process of the cover plate 12.

[0063] In one embodiment, each of the two opposite sides of the cover plate 12 located in the bending area A is provided with at least one first groove 121.

[0064] For example, the side of the cover plate 12 located in the bending area A is provided with a plurality of first grooves 121, and the number of first grooves 121 is greater than 3 (e.g., Figure 5 (As shown).

[0065] For example, the side of the cover plate 12 located in the bending area A is provided with two first grooves 121, respectively located at the ends of the side of the cover plate 12 located in the bending area A (see [reference]). Figure 6 , Figure 6(This is a schematic diagram of another embodiment of the first groove on the cover plate).

[0066] In one embodiment, along the bending axis of the bending region A, the crystallinity of the cover plate 12 in the middle region of the bending region A is less than the crystallinity of the cover plate 12 in the edge region of the bending region A (e.g., Figure 5 (As shown). Specifically, the portion of the cover plate 12 located in the bending area A is preheated in stages and segments, with a lower preheating temperature in the middle area and a higher preheating temperature in the two edge areas. It can be understood that the cover plate 12 is preheated before being bonded to other film layers such as the first adhesive layer 13. When bending area A is bent, it bends along the bending axis; the bending axis is a virtual axis and does not exist in the structure of the display panel; it is a concept introduced simply to accurately describe the different crystallinities of different areas of the cover plate 12. For example, the bending axis is the axis of symmetry M of the bending area A (e.g., ...). Figure 5 (As shown). It can be understood that the axis of symmetry M of the bending region A as the bending axis is only one embodiment of the bending axis, and is not limited to the axis of symmetry M of the bending region A as the bending axis. The specific position of the bending axis is designed according to the needs.

[0067] When the material of the cover plate 12 is PET, the presence of rigid benzene rings and short flexible carbonane segments in the PET molecular chain results in a slow crystallization (homogeneous nucleation) rate and low crystallinity during rapid melt cooling (such as injection molding), leading to poor mechanical strength, rigidity (dimensional stability), and heat resistance of the product. In this embodiment, the PET undergoes a pre-strengthening heat treatment to improve its crystallinity and reduce the crystallinity of the middle region of the cover plate 12 in the bending zone A compared to the edge region. This improves the heat resistance of the cover plate 12 while alleviating the stress on the edge region of the cover plate 12 in the bending zone A during bending, reducing shrinkage of other film layers after the cover plate 12 is applied, and preventing wrinkles. Furthermore, using different preheating temperatures to achieve different crystallinities in the middle and edge regions of the cover plate 12 in the bending zone A can alleviate the stress on the first adhesive layer 13 in the bending zone A, further improving the bending performance of the cover plate 12. It is understandable that when the material of the cover plate 12 is PEN, preheating the bending area A of the cover plate 12 can achieve a similar technical effect to PET, which will not be elaborated further.

[0068] Optionally, the cover plate 12 may be heat-treated at a temperature lower than its glass transition temperature, specifically, 35°C-60°C.

[0069] Optionally, the cover plate 12 is located in the bending zone A, and the crystallinity of the cover plate 12 gradually increases along the direction from the middle region to the edge region. Specifically, the portion of the cover plate 12 located in the bending zone A is preheated in stages and segments, with the preheating temperature gradually increasing from the middle region to the edge region.

[0070] Optionally, the cover plate 12 is located in the bending area A, and the crystallinity of the two edge regions of the cover plate 12 is the same.

[0071] For example, the portion of the cover plate 12 located in the bending area A is divided into five regions: a first edge region a, a first transition region b, a middle region c, a second transition region d, and a second edge region f. The preheating temperature of the middle region c is 35℃-45℃, the preheating temperature of the first transition region b and the second transition region d is 40℃-50℃, and the preheating temperature of the first edge region a and the second edge region f is 50℃-60℃ (e.g., ...). Figure 5 (As shown).

[0072] Please see Figure 7 , Figure 7 yes Figure 1 The diagram shows a top view of the support film of the display panel.

[0073] In this embodiment, the side of the support film 14 located in the bending area A is provided with at least one second groove 141. The orthogonal projection of the second groove 141 toward the screen body 11 is at least partially located on the screen body 11. That is, the side of the support film 14 located in the bending area A is recessed relative to the side of the screen body 11. This allows the long-range thermal shrinkage of the entire side of the support film 14 to be converted into short-range thermal shrinkage of the side of the support film 14 located in the bending area A when the support film 14 deforms under high temperature and high humidity conditions. This reduces the long-range adhesive stress of the second adhesive layer 15 along the entire side of the support film 14, which helps to eliminate the extrusion phenomenon of the second adhesive layer 15 located in the bending area A and avoids wrinkles at the edge of the support film 14 located in the bending area A. At the same time, by providing the second groove 141, deformation space is provided for the support film 14 during bending, further preventing wrinkles at the edge of the support film 14 located in the bending area A during bending, which helps to improve the bending performance of the display panel.

[0074] A second groove 141 is disposed on the support film 14 corresponding to the non-display area NA of the screen 11, and the depth of the second groove 141 is less than or equal to the width of the non-display area NA. It is understood that the non-display area NA typically contains circuitry, which is masked by ink, and the depth of the second groove 141 is less than or equal to the width of the ink. The depth and / or width of the second groove 141 are in the micrometer range.

[0075] In one embodiment, the cross-sectional shape of the second groove 141 along the direction parallel to the screen body 11 is an arc. By setting the cross-sectional shape of the second groove 141 to an arc, the arc is subjected to more uniform force compared to other shapes, which can avoid the generation of local cracks under pressure during the bending process of the support membrane 14.

[0076] In one embodiment, at least one second groove 141 is provided on each of the two opposite sides of the support membrane 14 located in the bending area A.

[0077] For example, the side of the support membrane 14 located in the bending area A is provided with a plurality of second grooves 141, and the number of second grooves 141 is greater than 3 (e.g., Figure 7 (As shown).

[0078] In one embodiment, along the bending axis of bending region A, the crystallinity of the support film 14 in the middle region of bending region A is less than that in the edge regions of bending region A. Specifically, the portion of the support film 14 in bending region A is preheated in stages and segments, with a lower preheating temperature in the middle region and a higher preheating temperature in the two edge regions. It is understood that the support film 14 is preheated before being bonded to other film layers such as the second adhesive layer 15.

[0079] When the material of the support film 14 is PET, the presence of rigid benzene rings and short flexible carbide segments in the PET molecular chain results in a slow crystallization (homogeneous nucleation) rate and low crystallinity during rapid melt cooling (such as injection molding), leading to poor mechanical strength, rigidity (dimensional stability), and heat resistance of the product. In this embodiment, the PET undergoes a pre-strengthening heat treatment to improve its crystallinity and reduce the crystallinity of the middle region of the support film 14 compared to the edge region. This improves the heat resistance of the support film 14 while alleviating the stress on the edge region of the support film 14 located in bending zone A during bending, reducing shrinkage of other film layers after the support film 14 is bonded, and preventing wrinkles. Furthermore, using different preheating temperatures for the middle and edge regions of the support film 14 to achieve different crystallinities can alleviate the stress on the second adhesive layer 15 located in bending zone A, further improving the bending performance of the support film 14. It is understandable that when the material of the support film 14 is PEN, preheating the bending area A of the support film 14 can achieve a similar technical effect to PET, which will not be elaborated further.

[0080] Optionally, the temperature at which the support film 14 is heat-treated is lower than its glass transition temperature, specifically, 35°C-60°C.

[0081] Optionally, in the portion of the support film 14 located in the bending region A, the crystallinity of the support film 14 gradually increases from the middle region to the edge region. Specifically, the portion of the support film 14 located in the bending region A is preheated in stages and segments, with the preheating temperature gradually increasing from the middle region to the edge region.

[0082] Optionally, the support film 14 is located in the portion of the bending region A, and the crystallinity of the two edge regions of the support film 14 is the same.

[0083] See also Figure 1 The display panel also includes a touch layer 16, a third adhesive layer 17, a polarizer 18, a fourth adhesive layer 19, and a metal support layer 20. The touch layer 16 and the polarizer 18 are sequentially disposed on the side of the screen body 11 near the cover plate 12; specifically, the touch layer 16 is disposed on the surface of the screen body 11 near the cover plate 12, and the polarizer 18 is disposed on the side of the touch layer 16 near the cover plate 12. The polarizer 18 is bonded to the touch layer 16 via the third adhesive layer 17, and the cover plate 12 is bonded to the polarizer 18 via the first adhesive layer 13. The metal support layer 20 is disposed on the side of the support film 14 away from the screen body 11, and the metal support layer 20 is bonded to the support film 14 via the fourth adhesive layer 19.

[0084] The metal support layer 20 is the bottommost support component of the display panel. The metal support layer 20 includes, but is not limited to, SUS301, SUS304, Ti alloy, and magnesium-aluminum alloy. The thickness of the metal support layer 20 is 30μm-500μm.

[0085] It should be noted that the selection of materials and structural design of the cover plate 12 provided above can be applied to display panels with double or multiple cover plates.

[0086] This application also provides an electronic device, which includes the display panel provided in any of the above embodiments, thereby improving the quality of the electronic device. The electronic device may be a desktop computer, laptop computer, personal digital assistant (PDA), mobile phone, television, etc.

[0087] The above are merely embodiments of this application and do not limit the scope of this patent application. Any equivalent structural or procedural changes made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A display panel, comprising a bent area and a non-bent area, characterized in that, include: Screen body; A cover plate is provided on one side of the screen body; The first adhesive layer is disposed on the surface of the cover plate near the screen body; A support membrane is disposed on the side of the screen body away from the cover plate; The second adhesive layer is disposed on the surface of the support film near the screen body; The material of the cover plate and / or the support film includes polyethylene terephthalate and / or polyethylene naphthalate, and the portion of its side located in the bending area is flush with the side of the screen or extends beyond the side of the screen by less than or equal to 0.1 mm. The side of the cover plate located in the bending area has at least one first groove; the orthogonal projection of the first groove toward the screen body is at least partially located on the screen body; and / or, the side of the support film located in the bending area has at least one second groove; the orthogonal projection of the second groove toward the screen body is at least partially located on the screen body; Along the bending axis of the bending region, the crystallinity of the cover plate in the middle region of the bending region is less than the crystallinity of the cover plate in the edge region of the bending region, and / or the crystallinity of the support film in the middle region of the bending region is less than the crystallinity of the support film in the edge region of the bending region.

2. The display panel according to claim 1, characterized in that, Along a direction parallel to the screen body, the cross-sectional shape of the first groove is an arc, and / or the cross-sectional shape of the second groove is an arc.

3. The display panel according to claim 1, characterized in that, The display panel includes a display area and a non-display area disposed at the edge of the display area, and the bending area spans the display area and the non-display area; the first groove is disposed on the cover plate corresponding to the non-display area of ​​the screen body, and the depth of the first groove is less than or equal to the width of the non-display area; and / or the second groove is disposed on the support film corresponding to the non-display area of ​​the screen body, and the depth of the second groove is less than or equal to the width of the non-display area.

4. The display panel according to claim 1, characterized in that, The crystallinity of the cover plate gradually increases along the direction from the middle region of the cover plate to the edge region of the cover plate in the portion of the bend area. And / or the portion of the support film located in the bending region, along the direction from the middle region of the support film to the edge region of the support film, the crystallinity of the support film gradually increases.

5. The display panel according to claim 4, characterized in that, The cover plate located in the bending area has the same crystallinity on both edge regions; and / or the support film located in the bending area has the same crystallinity on both edge regions.

6. The display panel according to claim 1, characterized in that, It also includes a touch layer, a polarizer, and a metal support layer; the touch layer and the polarizer are sequentially disposed on the side of the screen body near the cover plate, and the metal support layer is disposed on the side of the support film away from the screen body.

7. An electronic device, characterized in that, Includes the display panel as described in any one of claims 1-6.

8. A cover plate, comprising a bending area and a non-bending area, for protecting a screen body, characterized in that, The cover plate is made of polyethylene terephthalate and / or polyethylene naphthalate, and the portion of its side surface located in the bending area is flush with or extends beyond the side surface of the screen body by less than or equal to 0.1 mm; the portion of the cover plate's side surface located in the bending area is provided with at least one first groove; the orthographic projection of the first groove toward the screen body is at least partially located on the screen body; along the bending axis of the bending area, the crystallinity of the middle region of the cover plate located in the bending area is less than the crystallinity of the edge region of the cover plate located in the bending area.

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