A preparation method of a display module, a display module and electronic equipment

Abstract

The present disclosure provides a preparation method of a display module, a display module and an electronic device. The method comprises: binding a first device on a first surface of a binding area of a flexible display panel, the first surface being a surface of the binding area away from the display area in a state where the binding area is bent to the back light side of the display area; reversely binding an external circuit board on the first surface of the binding area of the flexible display panel, the external circuit board being provided with at least a first cavity, so that the first device is located in the first cavity, the height of the first cavity is greater than the thickness of the first device, and the orthographic projection of the first cavity on the first surface completely covers the orthographic projection of the first device on the first surface; injecting a preset glue into the first cavity through at least one glue injection channel penetrating through the external circuit board, the orthographic projection of the first cavity on the first surface completely covering the orthographic projection of the glue injection channel on the first surface; and curing the preset glue by using a preset curing method to fill the gap between the first device and the first surface.

Description

Technical Field

[0001] This disclosure relates to the field of display technology, and in particular to a method for preparing a display module, a display module, and an electronic device. Background Technology

[0002] With the development of the display market and the continuous expansion of flexible panel production scale, the proportion of display products made from flexible display panels in the entire display industry has further increased. In recent years, AMOLED (Active-matrix Organic Light-emitting Diode) flexible displays have brought users a better experience. After continuous accumulation, it is evident that the smartphone market shows high enthusiasm for AMOLED. As the market's requirements for AMOLED flexible display devices continue to increase, the reverse bonding process has become mainstream. The benefits of reverse bonding are that it provides customers with more space for device installation, and offers more room for customers to increase battery capacity and design operability.

[0003] In existing reverse bonding processes, the driver IC is first bonded and encapsulated on the flexible display panel, followed by reverse bonding of the external circuit board. To avoid interference between the external circuit board and the driver IC, slots need to be cut into the external circuit board to form a cavity after reverse bonding. Due to limitations in existing processes and equipment, the encapsulation of the driver IC cannot completely isolate moisture, and residual moisture inside the cavity may corrode the driver IC, affecting its connection performance and subsequent use. Summary of the Invention

[0004] The purpose of this disclosure is to provide a cover plate for flexible displays and a foldable display device, so as to solve the problem in the prior art that the impact resistance and bending performance of glass cannot be simultaneously achieved when glass is used as a display cover plate.

[0005] The embodiments of this disclosure adopt the following technical solution: a method for manufacturing a display module, the display module including at least a flexible display panel and an external circuit board, the flexible display panel including at least a display area and a bonding area, the manufacturing method including: bonding a first device to a first surface of the bonding area of ​​the flexible display panel, the first surface being the surface of the bonding area away from the display area when the bonding area is bent to the backlight side of the display area; bonding the external circuit board to the first surface of the bonding area of ​​the flexible display panel in the opposite direction, the external circuit board having at least a first cavity, the first device being located in the first cavity, the height of the first cavity being greater than the thickness of the first device, the orthographic projection of the first cavity on the first surface completely covering the orthographic projection of the first device on the first surface; injecting a preset adhesive into the first cavity through at least one injection channel penetrating the external circuit board, the orthographic projection of the first cavity on the first surface completely covering the orthographic projection of the injection channel on the first surface; curing the preset adhesive using a preset curing method to fill the gap between the first device and the first surface.

[0006] In some embodiments, the glue injection channel includes at least a glue injection hole and / or a glue injection opening.

[0007] In some embodiments, the diameter of the injection hole is greater than 0.1 mm.

[0008] In some embodiments, there is an overlapping area between the orthographic projection of the injection opening on the first surface and the orthographic projection of the first device on the first surface.

[0009] In some embodiments, curing the preset adhesive using a preset curing method includes curing the preset adhesive using moisture curing and / or heat curing.

[0010] In some embodiments, the preset adhesive is liquid tafelic adhesive.

[0011] In some embodiments, injecting a preset adhesive into the first cavity through at least one injection channel through the external circuit board includes: injecting the preset adhesive into the first cavity through at least one injection channel through the external circuit board until the height of the preset adhesive in the first cavity is greater than the thickness of the first device.

[0012] In some embodiments, before the external circuit board is reverse-bonded to the first side of the bonding area of ​​the flexible display panel, the method further includes: forming the first cavity and the glue injection channel on the external circuit board.

[0013] This disclosure also provides a display module, which is prepared according to the above-described preparation method.

[0014] This disclosure also provides an electronic device, which includes at least the display module described above.

[0015] The beneficial effects of this embodiment are as follows: by adjusting the preparation steps of the display module, the external circuit board is reverse-bonded after the first device is bonded, and the preset glue is injected into the first cavity through the glue injection channel and cured to achieve complete sealing of the first device, thereby achieving good waterproof and insulating effects. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a cross-sectional schematic diagram of a display module in the prior art;

[0018] Figure 2 This is a flowchart of the preparation method of the display module in the first embodiment of this disclosure;

[0019] Figure 3 This is a cross-sectional schematic diagram of the display module in the first embodiment of this disclosure;

[0020] Figure 4 This is another cross-sectional schematic diagram of the display module in the first embodiment of this disclosure;

[0021] Figure 5 This is a schematic diagram of the external circuit board from a top view in the first embodiment of this disclosure;

[0022] Figure 6 This is another cross-sectional schematic diagram of the display module in the first embodiment of this disclosure. Detailed Implementation

[0023] Various embodiments and features of this disclosure are described herein with reference to the accompanying drawings.

[0024] It should be understood that various modifications can be made to the embodiments described herein. Therefore, the above description should not be considered as limiting, but merely as an example of embodiments. Other modifications within the scope and spirit of this disclosure will be apparent to those skilled in the art.

[0025] The accompanying drawings, which are included in and form part of this specification, illustrate embodiments of the present disclosure and, together with the general description of the disclosure given above and the detailed description of the embodiments given below, serve to explain the principles of the disclosure.

[0026] These and other features of this disclosure will become apparent from the following description of preferred forms of embodiments given as non-limiting examples, with reference to the accompanying drawings.

[0027] It should also be understood that although this disclosure has been described with reference to some specific examples, many other equivalent forms of this disclosure can be definitively implemented by those skilled in the art, which have the features of the claims and are therefore within the scope of protection defined herein.

[0028] The above and other aspects, features and advantages of this disclosure will become more apparent when taken in conjunction with the accompanying drawings and in view of the following detailed description.

[0029] Specific embodiments of this disclosure are described thereafter with reference to the accompanying drawings; however, it should be understood that the claimed embodiments are merely examples of this disclosure, which may be implemented in various ways. Well-known and / or repeated functions and structures are not described in detail to avoid unnecessary or redundant details that could obscure this disclosure. Therefore, the specific structural and functional details claimed herein are not intended to be limiting, but merely to serve as the basis and representative basis for the claims to teach those skilled in the art to use this disclosure in a variety of substantially any suitable detailed structures.

[0030] This specification may use the phrases “in one embodiment,” “in another embodiment,” “in yet another embodiment,” or “in still another embodiment,” all of which may refer to one or more of the same or different embodiments according to this disclosure.

[0031] With the development of the display market and the continuous expansion of flexible panel production, the proportion of display products made from flexible display panels in the entire display industry has further increased. In recent years, AMOLED flexible displays have brought users a better experience. After continuous accumulation, it is evident that the smartphone market shows great enthusiasm for AMOLED. As the market's requirements for AMOLED flexible display devices continue to rise, the reverse bonding process has become mainstream. The benefits of reverse bonding include providing customers with more space for device installation and offering more room for customers to increase battery capacity and design operability.

[0032] In existing reverse bonding processes, the driver IC is first bonded and encapsulated on the flexible display panel, such as... Figure 1As shown, after the driver IC is bonded to the bonding area of ​​the flexible display panel, it is coated with UV adhesive and then cured by ultraviolet light. Subsequently, the external circuit board (FPC) is reverse-bonded. To avoid interference between the external circuit board and the driver IC, slots need to be cut into the external circuit board to form a cavity after reverse bonding. Due to limitations of existing processes and equipment, the UV adhesive can only be applied to the two long sides of the driver IC, meaning the encapsulation cannot completely isolate moisture. Residual moisture inside the cavity may corrode the driver IC, affecting its connection and subsequent use. Furthermore, the presence of the cavity creates a significant gap between the driver IC and the FPC, which may affect the stability and reliability of the driver IC.

[0033] To address the aforementioned issues, the first embodiment of this disclosure provides a method for manufacturing a display module. This method primarily targets display modules with flexible display panels and external circuit boards. Currently, display panels with bending characteristics are commonly used to achieve narrow bezels or even bezel-less effects in electronic devices. Furthermore, the bonding area in the flexible display panel, which is bent towards the backlight side of the display area, is used to bond and connect devices such as driver ICs and external circuit boards, providing more space for the overall installation. Figure 2 A flowchart of the manufacturing method of the display module in this embodiment is shown, which mainly includes steps S10 to S40:

[0034] S10, the first device is bonded to the first side of the bonding area of ​​the flexible display panel.

[0035] Figure 3 The diagram shows a cross-sectional view of the display module in this embodiment. Figure 3 As shown, the display module includes a flexible display panel 100 and an external circuit board 200. The flexible display panel 100 includes at least a display area 101 and a bonding area 102. The bonding area 102 is located around the display area 101, and a bending area 103 is included between them to achieve a bending effect. In the actual manufacturing process of the display module, the bonding area 102 is bent to the backlight side of the display area 101, and the bent bonding area 102 is arranged parallel to the display area 101. There is a hierarchical structure between them for support. The hierarchical structure for support includes, but is not limited to, the following: Figure 3 The display panel shown includes a U-film support layer, a PI base layer, a BKT bracket, and a bending tape. In actual fabrication, other layers such as support foam can also be used to achieve the support function; this embodiment does not impose any limitations. Additionally, a certain thickness of adhesive layer is adhered to the outside of the bending area 103 of the display panel to protect the bending area 103 and simultaneously provide a certain degree of insulation.

[0036] In this embodiment, after the bonding area 102 of the flexible display panel is bent to the backlight side of the display area 101, the surface of the side away from the display area 101 is referred to as the first surface (i.e., Figure 3 The first surface (the upper surface of the bonding area 102) should be provided with various bonding pins for bonding with various devices. The first device 300 mainly refers to the driver chip used to control the display effect within the display area 101, and can also be a timing control chip, power supply chip, or other chips. The number and position of the first devices 300 on the first surface need to be set according to the actual function, size, and other limitations of the first devices 300. This embodiment does not impose specific limitations, as long as the bonding between the first devices 300 and the first surface is completed.

[0037] S20, an external circuit board is reverse-bonded on the first side of the bonding area of ​​the flexible display panel.

[0038] After the first device 300 is bonded, the external circuit board 200 is bonded in reverse, and the wiring pins on the external circuit board 200 are connected to the corresponding wiring pins on the first surface. This is equivalent to attaching the external circuit board 200 to the first surface on the back side of the flexible display panel 100, thereby realizing communication between the components set on the external circuit board 200 and the flexible display panel 100.

[0039] To avoid interference between the external circuit board 200 and the first device 300, the external circuit board 200 in this embodiment also has a first cavity 201, so that when the external circuit board 200 is reverse-bonded to the first surface, the first device 300 is located exactly within the first cavity 201. (Refer to...) Figure 3 As shown. In this embodiment, the thickness h1 of the first cavity 201 should be at least greater than the thickness h2 of the first device 300, so that the top of the first device 300 does not contact the external circuit board 200, thus preventing signal crosstalk; at the same time, the orthographic projection of the first cavity 201 on the first surface should completely cover the orthographic projection of the first device 300 on the first surface, and try to ensure that there is no edge overlap between the orthographic projections of the two, so as to leave a certain space for subsequent steps to seal the first device 300.

[0040] S30, inject a preset adhesive into the first cavity through at least one injection channel that penetrates the external circuit board.

[0041] Generally, the thickness of the first device 300 is usually less than half the thickness of the external circuit board 200. Therefore, after the first cavity 201 is opened on the external circuit board 200, the corresponding position of the external circuit board 200 still has a certain thickness (i.e., the original thickness of the external circuit board 200 minus the height of the first cavity 201). At this position, at least one glue injection channel 202 penetrating the external circuit board 200 is provided. Preset glue 301 can be injected into the first cavity 201 through the glue injection channel 202. The preset glue 301 is used to fill the gap between the first device 300 and the first surface of the bonding area 102, thereby providing waterproof and insulating properties for the first device 300.

[0042] Specifically, the glue injection channel 202 is positioned corresponding to the location of the first cavity 201, facilitating the injection of a preset glue 301 into the first cavity 201. That is, the orthographic projection of the first cavity 201 on its first surface completely covers the orthographic projection of the glue injection channel 202 on its first surface. Simultaneously, the shape, number, and position of the glue injection channels 202 can be adjusted according to the heat dissipation requirements of the first device 300.

[0043] In some embodiments, the glue injection channel 202 can be a glue injection hole 2021 or a glue injection opening 2022. The glue injection hole 2021 is generally a cylindrical through hole that penetrates the external circuit board 200, which facilitates the glue syringe to be inserted into the first cavity 201. Figure 3 and Figure 4 In the cross-sectional schematic diagram shown, the glue injection channel 202 is implemented in the form of a glue injection hole 2021. In conjunction with the size of the syringe needle, the diameter of the glue injection hole 2021 should be at least greater than 0.1 mm. Figure 3 and Figure 4 The difference between them is that, Figure 3 Only one injection hole (2021) is shown in the image. Figure 4 The diagram shows two injection holes 2021, which can shorten the injection time during the injection of the preset glue 301, reducing the preparation time of a single display module. Furthermore, increasing the number of injection holes 2021 can also improve the heat dissipation of the first device 300 to some extent. It should be noted that in actual setup, the number and position of the injection holes 2021 can be adjusted based on the preparation time requirements and heat dissipation needs of a single display module. However, the routing of the external circuit board 200 itself should also be considered. Due to the design of the first cavity 201 and the injection channel 202, the hollowed-out portion of the external circuit board 200 cannot be used for routing. Therefore, the design of the injection channel 202 also needs to consider the balance in actual implementation.

[0044] The glue injection opening 2022 is an opening of a certain size and specific shape that penetrates the external circuit board 200. It facilitates the injection of the pre-set glue 301 and also takes into account the heat dissipation effect of the first device 300. Figure 5 The diagram shows an external circuit board 200 from a top-down perspective, where the dashed box represents the first cavity 201, and the solid box inside the dashed box represents the injection opening 2022. Figure 5 The gray-filled area represents the first device 300. The cross-sectional diagram corresponding to the dashed line AA' in the figure is shown below. Figure 6 As shown. The glue injection opening 2022, like the glue injection hole, needs to penetrate the external circuit board 200 to achieve communication with the first cavity 201. When using the glue injection opening 2022 to inject the pre-set glue 301, a certain overlap area can be defined between the orthographic projection of the glue injection opening 2022 on the first surface and the orthographic projection of the first device 300 on the first surface, which can better facilitate the heat dissipation of the first device 300. It should be noted that... Figure 5 The shape and position of the injection opening 2022 shown are for illustrative purposes only. When setting it up, it is also necessary to consider the manufacturing time requirements of a single display module, heat dissipation requirements, and the arrangement of traces in the external circuit board 200. This embodiment will not provide a detailed description.

[0045] In this embodiment, when injecting the pre-applied adhesive 301 using the injection channel 202, it should be ensured that the pre-applied adhesive 301 covers at least the entire area enclosed by the first cavity 201 in the first surface. This ensures that the gaps between the four edges of the first device 300 and the first surface are completely filled with the pre-applied adhesive 301, resulting in a good sealing effect during subsequent curing. When actually injecting the pre-applied adhesive 301, the height of the pre-applied adhesive 301 injected into the first cavity 201 can be determined by just filling the gaps between the edges of the first device 300 and the first surface. Figure 3 As shown in the shaded area, the height of the pre-applied adhesive 301 does not need to exceed the upper surface of the first device 300 on the side away from the first surface, so that it can have good heat dissipation conditions; in some cases, the pre-applied adhesive 301 can be injected until the height of the pre-applied adhesive 301 is greater than the thickness of the first device 300, such as... Figure 4As shown in the shaded area, this achieves complete sealing of the first device 300. This improves the sealing performance of the first device 300, completely isolating it from moisture by using pre-applied adhesive 301. Furthermore, the pre-applied adhesive 301 fills the gap between the first device 300 and the external circuit board 200 (i.e., the first cavity 201), reinforcing the first device 300 and further ensuring the stability of the display module. Therefore, the amount of pre-applied adhesive 301 injected into the first cavity 201 needs to be considered in conjunction with the size of the first cavity 201, heat dissipation requirements, and sealing requirements. Simultaneously, the amount of adhesive injected may also affect the number and size of the injection channels 202.

[0046] S40, a preset adhesive is cured using a preset curing method to fill the gap between the first component and the first surface.

[0047] After the pre-installed adhesive 301 is injected into the first cavity 201, it is still in liquid form and needs to be cured by a corresponding curing method to form an adhesive layer with good sealing performance, so as to fill the gap between the first device 300 and the first surface.

[0048] In this embodiment, due to the setting of the glue injection channel 202, the preset glue 301 already injected into the first cavity 201 cannot be cured by ultraviolet light or other methods. Therefore, its preset curing method mainly includes moisture curing or heat curing. Correspondingly, when selecting the preset glue 301, its curing method also needs to be considered. In this embodiment, tuffy glue with moisture-proof and insulating properties and good flowability is preferably used as the preset glue 301, which can achieve the curing effect by moisture curing or heat curing. Furthermore, when selecting the preset glue 301, its thermal conductivity and curing time after curing can also be considered. By selecting a glue with good thermal conductivity and short curing time as the preset glue 301, the first device 300 can dissipate heat, and the preparation time of a single display module can be shortened.

[0049] This embodiment adjusts the manufacturing steps of the display module, performing reverse bonding of the external circuit board after the first device is bonded, and injecting a preset glue into the first cavity through the glue injection channel and curing it to achieve complete sealing of the first device, thereby achieving good waterproof and insulating effects.

[0050] It should be noted that the preparation process presented in steps S10 to S40 can be performed before or after the bonding area 102 is bent to the backlight side of the display area 101. This embodiment does not limit the specific execution time, and it can be combined with the actual preparation process and flow. In addition, before performing step S20, the external circuit board 200 should be improved by setting the first cavity 201 and the glue injection channel 202 on it, and a reasonable wiring layout should be made for the external circuit board 200 after the first cavity 201 and the glue injection channel 202 are opened. In addition, there may be more than one first device 300 on the first surface of the bonding area 102. Therefore, when setting the first cavity 201, the settings can be made according to the number, position, size and other conditions of the first device 300. For example, when two first devices 300 are bonded on the first surface, two first cavities 201 can be set on the external circuit board 200. Alternatively, a larger first cavity 201 can be opened to accommodate two first devices 300 at the same time. The setting of the glue injection channel 202 should also be adjusted accordingly. The specific settings can be based on the actual situation. This embodiment will not elaborate further.

[0051] The second embodiment of this disclosure provides a display module, which is mainly fabricated using the fabrication method provided in the first embodiment of this disclosure. This method improves the sealing performance of the first device bonded to the display panel, thereby making the fabricated display module more stable. Furthermore, the fabrication of other layers in the display module can be carried out according to conventional fabrication processes, which will not be described in detail in this embodiment.

[0052] The third embodiment of this disclosure provides an electronic device, which includes at least the display module of the second embodiment of this disclosure. It can be used in conjunction with other functional modules. The electronic device includes, but is not limited to, smartphones, tablets, laptops, televisions, and even vehicle central control systems. Especially for electronic devices such as mobile phones and vehicle central control systems that are frequently exposed to different external environments, strengthening the packaging effect of the components in the display module can improve the stability and reliability of the electronic device, enabling it to provide a stable user experience even under conditions such as high temperature and high humidity.

[0053] The foregoing has provided a detailed description of several embodiments of this disclosure. However, this disclosure is not limited to these specific embodiments. Those skilled in the art can make various variations and modifications based on the concept of this disclosure, and all such variations and modifications should fall within the scope of protection claimed by this disclosure.

Claims

1. A method for manufacturing a display module, characterized in that, The display module includes at least a flexible display panel and an external circuit board, the flexible display panel includes at least a display area and a bonding area, and the manufacturing method includes: A first device is bonded to a first surface of the bonding area of ​​the flexible display panel, wherein the first surface is the surface of the bonding area away from the display area when the bonding area is bent to the backlight side of the display area; The external circuit board is reverse-bonded to the first side of the bonding area of ​​the flexible display panel. The external circuit board has at least a first cavity so that the first device is located in the first cavity. The height of the first cavity is greater than the thickness of the first device. The orthographic projection of the first cavity on the first surface completely covers the orthographic projection of the first device on the first surface. Preset adhesive is injected into the first cavity through at least one injection channel that penetrates the external circuit board, and the orthographic projection of the first cavity on the first surface completely covers the orthographic projection of the injection channel on the first surface; the preset adhesive is cured using a preset curing method to fill the gap between the first device and the first surface. The glue injection channel is configured to correspond to the location of the first cavity; The glue injection channel includes at least a glue injection hole and / or a glue injection opening; There is an overlapping area between the orthographic projection of the injection opening on the first surface and the orthographic projection of the first device on the first surface.

2. The preparation method according to claim 1, characterized in that, The diameter of the injection hole is greater than 0.1 mm.

3. The preparation method according to claim 1, characterized in that, The curing of the preset adhesive using a preset curing method includes: The pre-set adhesive is cured using moisture curing and / or heat curing.

4. The preparation method according to claim 1, characterized in that, The pre-set adhesive is liquid tafelic acid glue.

5. The preparation method according to claim 1, characterized in that, The injection of a preset adhesive into the first cavity through at least one injection channel penetrating the external circuit board includes: Preset glue is injected into the first cavity through at least one glue injection channel that penetrates the external circuit board until the height of the preset glue in the first cavity is greater than the thickness of the first device.

6. The preparation method according to any one of claims 1 to 5, characterized in that, Before the external circuit board is reverse-bonded to the first side of the bonding area of ​​the flexible display panel, the following is also included: The first cavity and the glue injection channel are formed on the external circuit board.

7. A display module, characterized in that, The display module is prepared by the method according to any one of claims 1 to 6.

8. An electronic device, characterized in that, The electronic device includes at least the display module as described in claim 7.

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