Display module, preparation method of display module and display device

Abstract

The embodiment of the invention provides a display module, a preparation method of the display module and a display device, and relates to the technical field of display. The display module comprises a flexible display panel which comprises a flat plate part, a bending part and a fixing part, the flat plate part is connected with the bending part, the bending part is connected with the fixing part, and the fixing part is bent to the backlight side of the flat plate part through the bending part; the heat dissipation layer is arranged between the flat plate part and the fixing part; the protection glue layer is arranged on one side, far away from the heat dissipation layer, of the bending part; and the covering adhesive layer at least covers the side surface of the partial region of the bending part and the side surface of the protective adhesive layer at the partial region. According to the embodiment of the invention, the bending part is effectively protected through the covering adhesive layer, the bending part is prevented from having a stress concentration point, and the product yield of the display module is improved.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular, to a display module, a preparation method of the display module, and a display device. Background Art

[0002] With the development of electronic devices such as smart phones, consumers have higher and higher requirements for the screen-to-body ratio of the devices, and full-screen has become the mainstream trend. The narrow bezel design can not only provide a broader visual experience, but also achieve a larger display area within a limited device size, meeting the dual needs of users for portability and large-screen experience.

[0003] The flexible display screen has the characteristics of being bendable and foldable, which provides a basis for the application of the Chip On Panel (COP) packaging technology on the panel. The COP packaging technology can make full use of the flexible characteristics of the flexible screen, bend the flexible printed circuit (FPC) and IC chips of the screen under the screen, so as to minimize the occupation of the bezel space by the screen module and achieve a narrower lower bezel width. However, in the prior art, the bending area of the flexible display screen is easily affected by stress, causing cracks in the film layer of the bending part and resulting in abnormal screen display. Summary of the Invention

[0004] The present application provides a display module, a preparation method of the display module, and a display device, which are used to improve the problem of film layer cracks in the bending part of the flexible display screen in the prior art.

[0005] According to one aspect of the present application, a display module is provided, including:

[0006] A flexible display panel, including a flat part, a bending part, and a fixing part, the flat part is connected to the bending part, the bending part is connected to the fixing part, and the fixing part is bent to the backlight side of the flat part through the bending part;

[0007] A heat dissipation layer, disposed between the flat part and the fixing part;

[0008] A protective glue layer, disposed on the side of the bending part away from the heat dissipation layer;

[0009] A cover glue layer, covering at least the side surfaces of some areas of the bending part and the side surfaces of the protective glue layer at some areas.

[0010] In a possible implementation manner, the above cover glue layer includes a main body part, and the main body part covers at least the side surfaces of some areas of the bending part and the side surfaces of the protective glue layer disposed at some areas.

[0011] In a possible implementation, the above-mentioned covering glue layer further includes a first overflow part, which is located on the side of the main body part away from the heat dissipation layer and is connected to the main body part. The first overflow part covers the first edge area of the first surface of the protective glue layer. The first surface is the surface of the protective glue layer on the side away from the heat dissipation layer, and the first edge area is the area of the first surface adjacent to the main body part.

[0012] In another possible implementation, the above-mentioned covering glue layer further includes a second overflow part, which is located on the side of the main body part close to the heat dissipation layer and is connected to the main body part. The second overflow part covers the second edge area of the second surface of the bent part. The second surface is the surface of the bent part on the side close to the heat dissipation layer, and the second edge area is the area of the second surface adjacent to the main body part.

[0013] In another possible implementation, the above-mentioned bent part includes a first edge sub-part, a middle sub-part and a second edge sub-part. The first edge sub-part is connected to the flat part, the middle sub-part is located between the first edge sub-part and the second edge sub-part and is respectively connected to the first edge sub-part and the second edge sub-part, and the second edge sub-part is connected to the fixed part; the main body part covers the side surface of the middle sub-part and the side surface of the protective glue layer provided at the middle sub-part.

[0014] In another possible implementation, the central axis of the above-mentioned middle sub-part is the bending axis of the bent part.

[0015] In another possible implementation, the above-mentioned covering glue layer is one or more. When there are multiple covering glue layers, the multiple covering glue layers are arranged at intervals along the bending direction of the bent part, and each covering glue layer covers at least the side surface of a part of the bent part and the side surface of the protective glue layer at a part of the area.

[0016] In another possible implementation, along the direction perpendicular to the side surfaces of the bent part and the protective glue layer, the thickness of the covering glue layer is H, where 0.1mm ≤ H ≤ 0.15mm.

[0017] According to another aspect of the embodiments of the present application, a method for manufacturing a display module is provided, which is applied to the display module shown in the first aspect of the present application. The method includes:

[0018] Providing a flexible display panel; wherein, the flexible display panel includes a flat part, a bent part and a fixed part, the flat part is connected to the bent part, and the bent part is connected to the fixed part;

[0019] Providing a heat dissipation layer on the backlight side of the flat part;

[0020] Providing a protective glue layer on one side of the bent part;

[0021] Coating at least the side surface of a part of the bent part and the side surface of the protective glue layer at a part of the area with a covering glue layer;

[0022] The fixing part is bent to the backlight side of the flat part through the bending part, so that the heat dissipation layer is located between the flat part and the fixing part.

[0023] According to another aspect of the present application, a display device is provided, including the display module shown in the first aspect of the present application.

[0024] The display module, the preparation method of the display module and the display device provided by the present application can effectively protect the bending part by arranging a covering glue layer at least on the side surface of a partial area of the bending part and the side surface of the protective glue layer at this partial area. When the bending part is subjected to a torsional force, the film layers on the upper and lower surfaces of the bending part are prone to cracks under the action of the torsional force. The above-mentioned covering glue layer can effectively absorb the torsional force, avoid stress concentration points in the bending part, effectively improve the crack problem of the bending part of the flexible display panel, ensure the normal display of the display module, and improve the product yield of the display module. Description of the Drawings

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained according to these drawings without creative efforts.

[0026] Figure 1 It is a partial schematic diagram of a bending part of a display panel provided by an embodiment of the present application;

[0027] Figure 2 It is a schematic structural diagram of a display module provided by an embodiment of the present application;

[0028] Figure 3 It is a schematic structural diagram of a flexible display panel in a display module provided by an embodiment of the present application;

[0029] Figure 4 It is a stress simulation diagram of a bending part in a display module provided by an embodiment of the present application;

[0030] Figure 5 It is a schematic diagram of the stress simulation result of a bending part in a display module provided by an embodiment of the present application;

[0031] Figure 6-1 It is a schematic structural diagram of a display module before bending provided by an embodiment of the present application;

[0032] Figure 6-2 It is a partial cross-sectional view of a bending part in a display module provided by an embodiment of the present application;

[0033] Figure 7 It is a partial cross-sectional view of a bent portion in another display module provided by an embodiment of the present application;

[0034] Figure 8 It is a schematic structural diagram of another display module provided by an embodiment of the present application;

[0035] Figure 9 It is a front view of a flexible display panel in a display module provided by an embodiment of the present application;

[0036] Figure 10 It is a partial cross-sectional view of a bent portion in another display module provided by an embodiment of the present application;

[0037] Figure 11 It is a front view of a flexible display panel in another display module provided by an embodiment of the present application;

[0038] Figure 12 It is a schematic structural diagram of another display module provided by an embodiment of the present application;

[0039] Figure 13 It is a schematic structural diagram of another display module provided by an embodiment of the present application;

[0040] Figure 14 It is a schematic flow chart of a method for manufacturing a display module provided by an embodiment of the present application. Detailed implementation manners

[0041] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present disclosure. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts of the present disclosure.

[0042] Various schematic structural diagrams according to embodiments of the present disclosure are shown in the accompanying drawings. These figures are not drawn to scale, where for the purpose of clear expression, some details are enlarged and some details may be omitted. The shapes of various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary, and in practice, there may be deviations due to manufacturing tolerances or technical limitations, and those skilled in the art can design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0043] In the context of the present disclosure, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. Additionally, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element.

[0044] Flexible organic light-emitting diode (OLED) screens have the characteristics of being bendable and foldable, which provides a basis for the application of the Chip On Plastic (COP) packaging technology. The COP packaging technology can make full use of the flexible characteristics of flexible OLED screens, bend the flexible printed circuit (FPC) of the screen and the integrated circuit (IC) chip under the screen, thus minimizing the occupation of the border space by the screen module and achieving a narrower chin width.

[0045] The COP packaging of flexible display screens requires the use of high-performance flexible materials, such as transparent polyimide film (CPI). These materials need to have good flexibility, high temperature resistance, optical transparency, and mechanical strength to ensure that there are no problems such as fracture, deformation, or performance degradation during the bending process.

[0046] The COP packaging process requires high-precision operation and control. During the process of bending the IC chip and the FPC under the screen, it is necessary to ensure that the electrical connection between the chip and the screen is stable and reliable, and at the same time avoid damage to the chip and the circuit caused by the stress generated during bending. In addition, the control of the bending radius is also crucial. An overly small bending radius may cause material fatigue and affect the service life of the screen.

[0047] The complexity of the COP packaging technology results in higher production costs and lower yield rates. Due to high process requirements, high equipment precision requirements, and high material costs, various problems are likely to occur during the production of COP-packaged screens, such as poor electrical connection and abnormal screen display, thus reducing the yield rate of products.

[0048] Based on the above technical problems, in some embodiments of the present application, through the bending portion of the flexible display panel, the fixing portion is bent to the backlight side of the flat portion, a heat dissipation layer is provided between the flat portion and the fixing portion, and a protective adhesive layer is provided on the side of the bending portion away from the heat dissipation layer. Furthermore, a cover adhesive layer is covered at least on the side surface of at least a part of the bending portion and the side surface of the protective adhesive layer at this part of the region; by providing a cover adhesive layer at least on the side surface of at least a part of the bending portion and the side surface of the protective adhesive layer at this part of the region, the bending portion can be effectively protected. When the bending portion is subjected to a torsional force, the film layers on the upper and lower surfaces of the bending portion are prone to crack under the action of the torsional force. As Figure 1 shown, it is a partial schematic diagram of the bending portion of the display panel, and the red arrow indicates the crack position. The above-mentioned cover adhesive layer can effectively absorb the torsional force, avoid stress concentration points in the bending portion, effectively improve the crack problem of the bending portion of the flexible display panel, ensure the normal display of the display module, and improve the product yield rate of the display module.

[0049] Next, specific embodiments will be used to elaborate in detail on the technical solutions of the present application and how the technical solutions of the present application solve the above technical problems. The following several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of the present application will be described below with reference to the accompanying drawings.

[0050] In an embodiment of the present application, a display module is provided, as Figure 2 shown. The display module includes a flexible display panel 10; wherein, Figure 2 The dashed line shown is used to divide each connection part of the flexible display panel 10. The flexible display panel 10 includes a flat part 111, a bending part 112, and a fixing part 113. The flat part 111 is connected to the bending part 112, the bending part 112 is connected to the fixing part 113, and the fixing part 113 is bent to the backlight side of the flat part 111 through the bending part 112.

[0051] Optionally, the flexible display panel 10 may include a display area, a bending area, and a bonding area. The bonding area is located on the side of the bending area away from the display area. In some embodiments, the display area may be located on the flat part 111, the bonding area may be located on the above-mentioned fixing part 113; the bending area may be located on the bending part 112. It should be noted that the area involved in the bending part 112 can be determined according to the needs of the actual product and is not specifically limited in the embodiments of the present application. For example, in other embodiments, some areas of the bonding area close to the bending area may be located on the bending part 112, and the remaining areas are located on the fixing part 113.

[0052] The display area includes a plurality of pixel units arranged in an array, and the actual arrangement of the pixel units can be determined according to the needs of the product. Each pixel unit includes a plurality of sub-pixels, and each sub-pixel can display a single color. For example, the above-mentioned plurality of sub-pixels may include a first sub-pixel, a second sub-pixel, and a third sub-pixel, and the first sub-pixel, the second sub-pixel, and the third sub-pixel are sub-pixels of different colors, such as can respectively display one of the three primary colors of red, green, and blue. The brightness (gray scale) of the sub-pixels of different colors in each pixel unit can be adjusted, and a variety of colors can be displayed through color combination and superposition, thereby realizing full-color display. Each sub-pixel may include a light-emitting device and a pixel driving circuit for driving the light-emitting device to emit light.

[0053] The bending region is a transition region in the flexible display panel for connecting the display region and the bonding region. It has a certain flexibility and can realize the bending function of the display panel, enabling the display panel to be folded or bent to a certain extent to meet the design requirements of different devices. The bonding region is the region on the display panel for electrical connection with external circuits (such as flexible printed circuit boards, driving IC chips, etc.). The bonding region mainly includes structures such as pads and traces for connecting external circuits. These pads and traces are usually made of metal materials such as copper and aluminum to ensure good electrical conductivity.

[0054] Figure 3 The schematic structural diagram of the flexible display panel according to some embodiments of the present application is shown. As Figure 3 shown, the above flexible display panel may include: a substrate layer, and a pixel driving layer, a pixel defining layer 260, and a plurality of light-emitting devices 270 disposed on one side of the substrate layer.

[0055] The pixel driving layer is located in the display region and is at least configured to form a pixel driving circuit for each sub-pixel. As Figure 3 shown, the pixel driving layer may include: a first active layer 241, a first gate dielectric layer 242, a first gate metal layer 243, a second gate dielectric layer 244, a second gate metal layer 245, a first interlayer insulating layer 246, a second buffer layer 247, a second active layer 248, a third gate dielectric layer 249, a third gate metal layer 251, a second interlayer insulating layer 252, a first source-drain metal layer 253, a passivation layer 254, a first planarization layer 255, a second source-drain metal layer 256, a second planarization layer 257, a third source-drain metal layer 258, and a third planarization layer 259. For example, the material of the first active layer 241 includes low-temperature polysilicon to form a low-temperature polysilicon transistor. The material of the second active layer 248 includes a metal oxide such as IGZO (Indium Gallium Zinc Oxide) to form an oxide transistor. The first gate metal layer 243 (Gate1), the second gate metal layer 245 (Gate2), and the third gate metal layer 251 (Gate3) can be configured to form the gates of the transistors in the pixel driving circuit, form capacitors, and form scan signal lines; the first source-drain metal layer 253 (SD1) can be configured to form data signal lines and the sources and drains of the transistors; the second source-drain metal layer 256 (SD2) can be configured to form power supply signal lines; the third source-drain metal layer 258 (SD3) can be configured to form the anode connection part of the light-emitting device, and the pixel driving circuit can be electrically connected to the anode of the light-emitting device through the anode connection part.

[0056] As Figure 3As shown, the flexible display panel may further include a second barrier layer 210, a metal shielding layer (Bottom Shield Metal, BSM) 220, and a first buffer layer 230 disposed between the substrate layer 100 and the driving circuit layer. For example, the second barrier layer 210 may include a first sub-barrier layer 211 and a second sub-barrier layer 212. The metal shielding layer 220 may be disposed between the first sub-barrier layer 211 and the second sub-barrier layer 212, and the first buffer layer 230 is disposed between the second sub-barrier layer 212 and the first active layer 241. In some embodiments, the orthographic projection of the metal shielding layer 220 on the substrate layer 100 may cover the orthographic projection of the driving transistor in the pixel driving circuit on the substrate layer 100, which is beneficial to shielding the influence of static electricity on the driving transistor and reducing the influence of external light incident from one side of the substrate layer 100 on the active layer of the driving transistor.

[0057] As Figure 3 shown, the substrate layer 100 may include a first flexible substrate layer 101, a second flexible substrate layer 103, and a first barrier layer 102 laminated between the first flexible substrate layer 101 and the second flexible substrate. The material of the flexible substrate layer may include, for example, a PI (Polyimide) substrate, a PET (Polyethylene Terephthalate) substrate, or a PEN (Polyethylene naphthalate two formic acid glycolester) substrate, etc.

[0058] The pixel defining layer 260 is disposed on the side of the second insulating layer 130 away from the substrate layer 100. The pixel defining layer 260 has a plurality of pixel openings 261 spaced apart in the display area. The light-emitting device 270 is disposed at the pixel opening 261, and the pixel opening 261 is configured to define the light-emitting area of the light-emitting device 270. For example, one light-emitting device 270 may be disposed at one pixel opening 261. For example, Figure 3 the pixel defining layer 260 in

[0059] For example, taking the light-emitting device 270 as an OLED device, in a direction away from the substrate layer 100, the light-emitting device 270 may include an anode layer 271, a light-emitting layer 272, and a cathode layer 273 that are sequentially stacked. The anode layer 271 is disposed between the pixel defining layer 260 and the driving circuit layer. The anode layers 271 of two adjacent light-emitting devices 270 are spaced apart and insulated from each other. The anode layer 271 is electrically connected to the pixel driving circuit, and at least a partial region of the anode layer 271 is exposed at the pixel opening 261. For example, the lower port of the pixel opening 261 (i.e., the opening 131 on the surface closer to the substrate layer 100) is within the range of the orthographic projection of the anode layer 271 on the substrate layer 100.

[0060] The light-emitting layer 272 is disposed on the side of the anode away from the substrate layer 100. For example, at least a partial region of the light-emitting layer 272 is located within the pixel opening 261 of the corresponding sub-pixel and forms an electrical connection with the anode layer 271 of the light-emitting device 270 to which it belongs. In some embodiments, the light-emitting layer 272 may include a light-emitting material layer (EML) and a functional material layer stacked with the light-emitting material layer. For example, the functional material layer may include one or more of a hole injection layer (HIL), a hole transport layer (HTL), an electron transport layer (ETL), and an electron injection layer (EIL), which is specifically set according to actual needs, and the present disclosure does not limit this.

[0061] The cathode layer 273 is stacked on the side of the light-emitting layer 272 away from the substrate layer 100. In some embodiments, the cathode layers 273 of adjacent light-emitting devices 270 may be connected together, such as Figure 3 being integrally provided as shown, so as to facilitate access to the cathode voltage signals of each light-emitting device 270. In other embodiments, the cathode layers 273 of each light-emitting device 270 may also be spaced apart from each other, and electrical connection between them is achieved through an additional conductive structure such as a metal isolation column.

[0062] In some embodiments, the anode layer 271 may be a composite structure composed of a transparent conductive oxide thin film / metal thin film / transparent conductive oxide thin film stacked in sequence. Among them, the material of the above transparent conductive oxide thin film is, for example, any one of ITO (Indium tin oxide) and IZO (Indium zinc oxide), and the material of the above metal thin film may be, for example, any one or more of aluminum (Al), silver (Ag), titanium (Ti), molybdenum (Mo), etc. In other embodiments, the anode layer 271 may also be a single-layer structure, and the material of the single-layer structure may be any one of aluminum (Al), silver (Ag), titanium (Ti), molybdenum (Mo).

[0063] In some embodiments, the cathode layer 273 may be made of any one of metal materials such as lithium (Li), aluminum (Al), magnesium (Mg), silver (Ag), etc., or an alloy of any combination of the above materials such as magnesium-silver alloy and aluminum-lithium alloy. In some embodiments, the anode layer 271 may serve as a reflective electrode, and the cathode layer 273 is configured to transmit and reflect part of the light emitted by the light-emitting layer 272. By using the microcavity effect, the light-emitting device 270 can achieve a better color gamut and luminous efficiency.

[0064] As Figure 3 shown, the flexible display panel further includes a packaging layer 280. The packaging layer 280 covers the plurality of light-emitting devices 270 to protect the light-emitting devices 270 from water and oxygen erosion. For example, the packaging layer 280 may include a first inorganic packaging layer, an organic packaging layer, and a second inorganic packaging layer stacked. For example, the first inorganic packaging layer and the second inorganic packaging layer may be made of an inorganic insulating material such as nitride, oxide, oxynitride, nitrate, carbide, or any combination thereof. The organic packaging layer may be made of an organic insulating material such as acrylic fiber, hexamethyldisiloxane, polyacrylate, polycarbonate, or polystyrene.

[0065] In some embodiments, the flexible display panel 10 may further include a touch structure layer 290 disposed on the side of the packaging layer away from the substrate layer 100 to facilitate the implementation of the touch function. For example, the touch structure layer 290 may be prepared by using FMLOC (Flexible Multi Layer On Cell) technology. For details, reference may be made to related technologies. For example, the touch structure layer 290 may include a first touch metal layer, a second touch metal layer, and a touch insulating layer disposed between the first touch metal layer and the second touch metal layer. The orthographic projections of the first touch metal layer and the second touch metal layer on the substrate layer 100 do not overlap with the orthographic projection of the pixel opening 261 on the substrate layer 100. One of the first touch metal layer and the second touch metal layer is configured to arrange a first touch electrode and a second touch electrode, and the other is configured to arrange a bridging portion for bridging the first touch electrode or the second touch electrode. The extending directions of the first touch electrode and the second touch electrode intersect with each other. For example, they may be perpendicular to each other. Taking the first touch metal layer as the bridging electrode and the second touch metal layer as the first touch electrode and the second touch electrode as an example, the second touch electrode includes a plurality of electrode units. Adjacent two electrode units are disconnected at the position where they cross the first touch electrode, and vias are provided in the touch insulating layer, and are bridged by the bridging electrode provided in the first touch metal layer.

[0066] In some embodiments, the flexible display panel 10 may further include a protective layer 300 (which may also be referred to as TOC), disposed on the side of the pixel defining layer 260 away from the substrate layer 100. For example, in the case where the flexible display panel 10 includes a touch structure layer 290, the protective layer 300 may be disposed on the side of the touch structure layer 290 away from the substrate layer 100 to protect the flexible display panel 10 from water and oxygen erosion in the air.

[0067] In an embodiment of the present application, a possible implementation is provided. The display module may further include a heat dissipation layer 114, a polarizer (POL) layer 115, and a polarizer protection film (POL PF) layer 116. The heat dissipation layer 114 is disposed between the flat portion 111 and the fixing portion 113; the polarizer layer 115 is disposed on the side of the flat portion 111 away from the heat dissipation layer 114, that is, the light-emitting side of the flat portion 111.

[0068] Optionally, the display module may further include a bending spacer 119 and an IC chip 120. The bending spacer 119 is disposed between the heat dissipation layer 114 and the fixing portion 113, and the IC chip 120 is disposed on the side of the fixing portion 113 away from the bending spacer 119.

[0069] Optionally, the heat dissipation layer 114 may be a Super Clean Foam (SCF). SCF is a composite material composed of multiple layers of materials, mainly used for heat dissipation, buffering, electromagnetic shielding, and bonding of the display module. It generally includes a base layer, a foam layer, a graphite layer, a support layer, and a conductive metal layer; in a flexible OLED display module, the SCF heat dissipation layer can achieve the functions of buffering, light shielding, and heat dissipation, and can also be closely attached to the flexible display panel 10 to ensure the overall flatness.

[0070] Optionally, the polarizer protection film layer 116 is disposed on the side of the polarizer layer 115 away from the flat portion 111. On the one hand, when external ambient light (such as sunlight or indoor light) irradiates the metal electrodes of the OLED flexible display panel 10, reflected light will be generated, interfering with the display effect and reducing the contrast and visibility. The polarizer can improve the display effect of the OLED screen at different angles through special optical design, reduce glare and reflection, and enable the screen to maintain good visibility in a strong light environment. On the other hand, POL PF is used to temporarily protect the surface of the polarizer to ensure that the polarizer will not be damaged in subsequent assembly and processing steps. The use of POL PF can significantly improve the yield rate of the display screen and ensure that the polarizer maintains good optical performance during the production process. After the final display module product is assembled, POL PF is usually removed.

[0071] In an embodiment of the present application, a possible implementation is provided. The display module may further include a protective adhesive layer 117 disposed on the side of the bending portion 112 away from the heat dissipation layer 114. The material of the protective adhesive layer 117 may include Metal Conductive Lacquer (MCL). MCL has high transparency, high barrier properties, good adhesion and flexibility, and can be used to protect the metal lines and sensitive components of the bending portion 112, preventing moisture, oxygen and other environmental factors from damaging the display module.

[0072] Optionally, the display module may further include a cover adhesive layer 118, and the cover adhesive layer 118 covers at least the sides of a partial area of the bending portion 112 and the sides of the protective adhesive layer 117 at the partial area.

[0073] In some embodiments, the cover adhesive layer may be coated over the entire surface. For example, the cover adhesive layer may cover the sides of the entire bending portion area and the sides of the protective adhesive layer at the entire bending portion area.

[0074] In other embodiments, the cover adhesive layer may also be coated at intervals. For example, the cover adhesive layer may cover the sides of a partial bending portion area and the sides of the protective adhesive layer at the partial bending portion area.

[0075] The cover adhesive layer 118 may be an Ultraviolet Adhesive (UV), and its material may be the same as that of the protective adhesive layer 117. The cover adhesive layer 118 has good wrapping properties and can cover the side areas of the bending portion 112 and the protective adhesive layer 117, making the bonding between the protective adhesive layer 117 and the bending portion 112 more firm. At the same time, the cover adhesive layer 118 can well absorb the stress received by the bending portion 112. For example, when opposite torsional stresses perpendicular to the upper surface of the bending portion 112 act on both ends of the bending portion 112, the cover adhesive layer 118 can absorb the torsional force, avoid the deformation of the bending portion 112, and improve the risk of film layer cracks of the flexible display panel 10.

[0076] In some embodiments, before coating the cover adhesive layer 118, torque force simulation may be performed on the bending portion 112, and opposite torsional stresses perpendicular to the upper surface of the bending portion are applied to both ends of the bending portion, as Figure 4 shown, where the red arrow is the direction of the torsional stress; the stress simulation result of the bending portion is as Figure 5 shown, and the red area within the red box is the stress concentration area. The coating range of the cover adhesive layer can be determined according to the above stress simulation result.

[0077] In the embodiment of the present application, through the bending portion 112 of the flexible display panel, the fixing portion 113 is bent to the backlight side of the flat portion 111, a heat dissipation layer 114 is provided between the flat portion 111 and the fixing portion 113, and a protective adhesive layer 117 is provided on the side of the bending portion 112 away from the heat dissipation layer 114. Furthermore, a covering adhesive layer 118 is covered at least on the side surface of a partial area of the bending portion 112 and the side surface of the protective adhesive layer 117 at this partial area; by providing the covering adhesive layer 118 at least on the side surface of a partial area of the bending portion 112 and the side surface of the protective adhesive layer 117 at this partial area, the bending portion 112 can be effectively protected. When the bending portion 112 is subjected to a torsional force, the film layers on the upper and lower surfaces of the bending portion 112 are likely to crack under the action of the torsional force. The above-mentioned covering adhesive layer 118 can effectively absorb this torsional force, avoid the existence of stress concentration points in the bending portion 112, effectively improve the crack problem of the bending portion 112 of the flexible display panel 10, ensure the normal display of the display module, and improve the product yield of the display module.

[0078] In a possible implementation manner provided in the embodiment of the present application, the above-mentioned covering adhesive layer 118 includes a main body portion, and the main body portion covers the side surface of at least a partial area of the bending portion 112 and the side surface of the protective adhesive layer 117 provided at at least a partial area.

[0079] Optionally, as Figure 6-1 shown is a schematic structural diagram of the display module before bending. As Figure 6-2 shown, taking Figure 6-1 the dotted line therein as the section line, it is a partial sectional view in the Z-axis direction. The upper surface of the main body portion 601 does not exceed the surface of the protective adhesive layer 117 away from the flexible display panel 10, and the lower surface of the main body portion 601 does not exceed the surface of the bending portion 112 close to the heat dissipation layer 114.

[0080] In a possible implementation manner provided in the embodiment of the present application, along the direction perpendicular to the side surfaces of the bending portion and the protective adhesive layer, the thickness of the covering adhesive layer is H, where 0.1 mm ≤ H ≤ 0.15 mm.

[0081] In a possible implementation manner provided in the embodiment of the present application, as Figure 7 shown, taking Figure 6-1 the dotted line therein as the section line, it is another partial sectional view in the Z-axis direction. The above-mentioned covering adhesive layer 118 further includes a first overflow portion 602. The first overflow portion 602 is located on the side of the main body portion 601 away from the heat dissipation layer 114 and is connected to the main body portion 601. The first overflow portion 602 covers the first edge area of the first surface of the protective adhesive layer 117; wherein, as Figure 8 shown, the first surface 801 is the surface of the protective adhesive layer 117 away from the heat dissipation layer 114, and the first edge area is the area of the first surface adjacent to the main body portion.

[0082] Optionally, as shown in Figure 9 FIG. Figure 9 is a front view of the light-emitting side of the flexible display panel 10 before bending. The protective glue layer 117 is disposed on the light-emitting side of the bending portion 112. First overflow portions 602 are disposed on both sides of the protective glue layer 117, and the first overflow portions 602 are connected to the main body portion 601 on the side surface of the bending portion 112.

[0083] In the embodiment of the present application, by providing the first overflow portion covering the glue layer on the first surface of the bending portion, the first overflow portion and the main body portion can better protect the bending portion of the flexible display panel on multiple sides, which can enhance the wrapping property of the covering glue layer for the bending portion, ensure the absorption efficiency of the torsional stress for the bending portion, further improve the problem of the mold layer crack of the bending portion of the flexible display panel, and effectively improve the user experience.

[0084] A possible implementation manner is provided in the embodiment of the present application. As shown in Figure 10 FIG. Figure 10 is another partial sectional view in the Z-axis direction with the dotted line in FIG. Figure 10 as the section line. The above-mentioned covering glue layer 118 further includes a second overflow portion 603. The second overflow portion 603 is located on the side of the main body portion 601 close to the heat dissipation layer 114 and is connected to the main body portion 601. The second overflow portion 603 covers the second edge region of the second surface of the bending portion 112; wherein, as shown in Figure 6-1 FIG. Figure 6-1 , the second surface 802 is the surface of the bending portion 112 on the side close to the heat dissipation layer 114, and the second edge region is the region adjacent to the main body portion on the second surface. Figure 8 FIG. Figure 8

[0085] Optionally, as shown in Figure 11 FIG. Figure 11 is a front view of the backlight side of the flexible display panel 10. The protective glue layer 117 is disposed on the backlight side of the bending portion 112. Second overflow portions 603 are disposed on both sides of the protective glue layer 117, and the second overflow portions 603 are connected to the main body portion 601 on the side surface of the bending portion 112.

[0086] A possible implementation manner is provided in the embodiment of the present application. As shown in Figure 12 FIG. Figure 12 , the above-mentioned bending portion 112 includes a first edge sub-portion 1121, an intermediate sub-portion 1122, and a second edge sub-portion 1123. The first edge sub-portion 1121 is connected to the flat portion 111. The intermediate sub-portion 1122 is located between the first edge sub-portion 1121 and the second edge sub-portion 1123 and is respectively connected to the first edge sub-portion 1121 and the second edge sub-portion 1123. The second edge sub-portion 1123 is connected to the fixing portion 113; the main body portion 601 covers the side surface of the intermediate sub-portion 1122 and the side surface of the protective glue layer 117 disposed at the intermediate sub-portion.

[0087] A possible implementation manner is provided in the embodiment of the present application. The central axis of the above-mentioned intermediate sub-portion is the bending axis of the bending portion.

[0088] In an embodiment of the present application, by coating a covering adhesive layer on the side surface of the middle sub - portion of the bending portion and on the side surface of the protective adhesive layer provided at the middle sub - portion, since the central axis of the middle sub - portion is the bending axis of the bending portion, the main body portion of the covering adhesive layer can effectively wrap the middle sub - portion with the highest degree of bending, which can effectively improve the crack problem of the flexible display panel and increase the yield rate of the display module.

[0089] In an embodiment of the present application, a possible implementation manner is provided. The above - mentioned covering adhesive layer 118 can be one or more. When there are multiple covering adhesive layers 118, the multiple covering adhesive layers 118 are arranged at intervals along the bending direction of the bending portion 112, and each covering adhesive layer 118 covers at least the side surface of a partial area of the bending portion 112 and the side surface of the protective adhesive layer 117 at a partial area.

[0090] As Figure 13 shown, the display module may include three covering adhesive layers, namely a first covering adhesive layer 1181, a second covering adhesive layer 1182, and a third covering adhesive layer 1183. The three covering adhesive layers are arranged at intervals along the bending direction of the bending portion 112, and each covering adhesive layer covers at least the side surface of a partial area of the bending portion 112 and the side surface of the protective adhesive layer 117 at a partial area.

[0091] An embodiment of the present application provides a method for manufacturing a display module, which is applied to the display module shown in the first aspect of the embodiment of the present application. As Figure 14 shown, the method includes:

[0092] S101, providing a flexible display panel.

[0093] Among them, the flexible display panel includes a flat portion, a bending portion, and a fixing portion. The flat portion is connected to the bending portion, and the bending portion is connected to the fixing portion.

[0094] S102, arranging a heat - dissipation layer on the backlight side of the flat portion; arranging a protective adhesive layer on one side of the bending portion.

[0095] S103, coating at least a covering adhesive layer on the side surface of a partial area of the bending portion and on the side surface of the protective adhesive layer at a partial area.

[0096] Among them, the above - mentioned covering adhesive layer can be determined based on the stress concentration points of the flexible display panel; the stress concentration points can be obtained through stress analysis and simulation of the bending portion.

[0097] S104, bending the fixing portion to the backlight side of the flat portion through the bending portion, so that the heat - dissipation layer is located between the flat portion and the fixing portion.

[0098] The method of the embodiment of the present application can be applied to the display module provided by the embodiment of the present application, and its implementation principle is similar. The steps in the method of each embodiment of the present application correspond to the preparation processes of the components of the display module in the first aspect of the embodiment of the present application, which will not be elaborated here.

[0099] In the embodiment of the present application, through the bending part of the flexible display panel, the fixing part is bent to the backlight side of the flat part, a heat dissipation layer is arranged between the flat part and the fixing part, and a protective adhesive layer is arranged on the side of the bending part away from the heat dissipation layer. Furthermore, a covering adhesive layer is covered at least on the side surface of a partial area of the bending part and the side surface of the protective adhesive layer at this partial area. By arranging the covering adhesive layer at least on the side surface of a partial area of the bending part and the side surface of the protective adhesive layer at this partial area, the bending part can be effectively protected. When the bending part is subjected to a torsional force, the film layers on the upper and lower surfaces of the bending part are prone to crack under the action of the torsional force. The above-mentioned covering adhesive layer can effectively absorb this torsional force, avoid stress concentration points in the bending part, effectively improve the crack problem of the bending part of the flexible display panel, ensure the normal display of the display module, and improve the product yield of the display module.

[0100] An embodiment of the present application provides a display device, including the display module shown in the first aspect of the embodiment of the present application. The display device can be a flexible display device such as a mobile phone screen, a tablet computer, or a curved TV set, which is not specifically limited here.

[0101] In the above description, technical details such as the composition of each layer are not elaborated in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of the required shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not exactly the same as the methods described above. In addition, although the above embodiments are described separately, this does not mean that the measures in each embodiment cannot be used in combination advantageously.

[0102] Although the preferred embodiments of the present application have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted to include the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0103] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalent technologies, the present application also intends to include these changes and modifications.

Claims

1. A display module, characterized in that: include: A flexible display panel, comprising a flat portion, a bending portion and a fixed portion, wherein the flat portion is connected to the bending portion, the bending portion is connected to the fixed portion, and the fixed portion is bent to the backlight side of the flat portion through the bending portion; A heat dissipation layer, disposed between the flat plate portion and the fixing portion; A protective adhesive layer, arranged on a side of the bent portion away from the heat dissipation layer; The covering adhesive layer at least covers the side surfaces of a partial area of ​​the bending portion and the side surfaces of the protective adhesive layer in the partial area.

2. The display module according to claim 1, characterized in that: The covering adhesive layer comprises a main body portion, and the main body portion covers the side surface of at least a partial area of ​​the bending portion and the side surface of the protective adhesive layer disposed at at least a partial area.

3. The display module according to claim 2, characterized in that: The covering adhesive layer also includes a first overflow portion, which is located on a side of the main body away from the heat dissipation layer and connected to the main body. The first overflow portion covers a first edge area of ​​a first surface of the protective adhesive layer. The first surface is a surface of the protective adhesive layer away from the heat dissipation layer, and the first edge area is an area of ​​the first surface adjacent to the main body.

4. The display module according to claim 2, characterized in that: The covering glue layer also includes a second overflow portion, which is located on a side of the main body close to the heat dissipation layer and connected to the main body. The second overflow portion covers a second edge area of ​​the second surface of the bent portion. The second surface is a surface of the bent portion close to the heat dissipation layer, and the second edge area is an area of ​​the second surface adjacent to the main body.

5. The display module according to claim 2, characterized in that: The bending portion includes a first edge sub-portion, a middle sub-portion and a second edge sub-portion, the first edge sub-portion is connected to the flat plate portion, the middle sub-portion is located between the first edge sub-portion and the second edge sub-portion and is respectively connected to the first edge sub-portion and the second edge sub-portion, and the second edge sub-portion is connected to the fixing portion; the main body portion covers the side surfaces of the middle sub-portion and the side surfaces of the protective adhesive layer arranged at the middle sub-portion.

6. The display module according to claim 5, characterized in that: The central axis of the middle sub-section is the bending axis of the bending section.

7. The display module according to any one of claims 1 to 4, characterized in that: There are one or more covering rubber layers. When there are multiple covering rubber layers, the multiple covering rubber layers are arranged at intervals along the bending direction of the bending portion, and each covering rubber layer at least covers the side surfaces of a partial area of ​​the bending portion and the side surfaces of the protective rubber layer at the partial area.

8. The display module according to claim 1, characterized in that: Along a direction perpendicular to the bending portion and the side surface of the protective adhesive layer, the thickness of the covering adhesive layer is H, wherein 0.1 mm≤H≤0.15 mm.

9. A method for preparing a display module, applied to the display module according to any one of claims 1 to 7, characterized in that: include: A flexible display panel is provided; wherein the flexible display panel comprises a flat portion, a bent portion and a fixed portion, the flat portion is connected to the bent portion, and the bent portion is connected to the fixed portion; A heat dissipation layer is provided on the backlight side of the flat plate portion; A protective adhesive layer is provided on one side of the bending portion; Coating a covering adhesive layer at least on the side of a partial area of ​​the bending portion and the side of the protective adhesive layer at the partial area; The fixing portion is bent to the backlight side of the flat portion through the bending portion, so that the heat dissipation layer is located between the flat portion and the fixing portion.

10. A display device, characterized in that: A display module comprising any one of claims 1-8.

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