Bonding method of display module and display module

Abstract

The application relates to a display module bonding method and a display module. The method comprises the following steps: providing a display panel assembly, the display panel assembly comprising a panel assembly and a protective film which are arranged in a stacking mode along a first direction, and a flexible circuit board arranged on a side of the panel assembly away from the protective film; the panel assembly has a first electrode area; the flexible circuit board has a second electrode area, the second electrode area comprising a connecting area and a bare area; a glue groove is defined between a part of the flexible circuit board provided with the bare area and a side of the panel assembly close to the bare area along a second direction; the display panel assembly is rotated around an axis parallel to a third direction, so that an angle between the display panel assembly and a first reference plane is set to be an acute angle; the first reference plane is perpendicular to a gravity direction of the display panel assembly; glue is formed in the glue groove, so that the panel assembly and the flexible circuit board are bonded by the glue. The display module bonding method can effectively protect the electrodes of the flexible printed circuit board.

Description

Technical Field

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

[0002] Bonding is a process that connects a display panel to a flexible printed circuit board (FPC) using conductive adhesive, enabling electrical connection and signal transmission between the two. This process is widely used in the manufacturing of display modules to connect the display panel to an external circuit board, giving the panel functions such as power supply, display, and touch. During the bonding process, it is usually necessary to avoid exposing the electrodes of the flexible printed circuit board.

[0003] However, related technologies often struggle to effectively protect the electrodes of flexible printed circuit boards, resulting in poor protection and leaving some electrodes exposed, which affects circuit connectivity. Summary of the Invention

[0004] Therefore, it is necessary to provide a bonding method and display module for a display module, addressing the problem that it is usually difficult to effectively protect the electrodes of flexible printed circuit boards in related technologies, resulting in poor electrode protection and often leaving some electrodes of the flexible printed circuit board exposed, affecting the circuit connection effect.

[0005] According to one aspect of this application, a bonding method for a display module is provided, the bonding method for the display module comprising:

[0006] A display panel assembly is provided; the display panel assembly includes a panel assembly and a protective film stacked along a first direction, and a flexible circuit board disposed on the side of the panel assembly opposite to the protective film, the side of the panel assembly opposite to the protective film having a first electrode area, the flexible circuit board having a second electrode area, the second electrode area including a connection area connected to the first electrode area, and an exposed area protruding from the panel assembly along a second direction; a groove is defined between the portion of the flexible circuit board where the exposed area is disposed and the side of the panel assembly along the second direction near the exposed area;

[0007] The display panel assembly is rotated about an axis parallel to a third direction, such that the angle between the display panel assembly and the first reference plane is an acute angle; wherein the first direction, the second direction, and the third direction intersect each other; the first reference plane is perpendicular to the direction of gravity of the display panel assembly;

[0008] An adhesive is formed in the adhesive tank to bond the panel assembly and the flexible circuit board together.

[0009] The bonding method for the aforementioned display module tilts the display panel assembly, allowing the adhesive placed in the adhesive tray to flow and fill the gaps within the tray under gravity. This ensures the adhesive flows effectively to all locations within the tray, facilitating complete coverage of the exposed areas and improving protection. Furthermore, the tilt angle of the display panel assembly can be adjusted to prevent the adhesive from flowing onto the protective film, reducing the risk of the adhesive adhering to the protective film. Therefore, the bonding method for the display module of this application can form an adhesive with a suitable shape and specifications, providing excellent protection for the exposed areas of the second electrode region of the flexible circuit board while minimizing adhesion to the protective film, thus reducing the risk of the protective film being unable to be removed later. In other words, the bonding method for the display module of this application effectively protects the electrodes of the flexible printed circuit board.

[0010] In one embodiment, the panel assembly includes a display panel and a support film stacked on top of each other, the protective film being located on the side of the support film facing away from the display panel; the step of rotating the display panel assembly about an axis parallel to a third direction so that the angle between the display panel assembly and the first reference plane is set at an acute angle includes:

[0011] The display panel assembly is placed on an operating table, and the operating table is rotated about an axis parallel to a third direction to drive the display panel assembly to rotate. The tilt angle r between the display panel assembly and the first reference plane satisfies: b1 / (m+0.5)<tan(r)<b2 / (m+0.5); where m is the length of the exposed area protruding from the display panel, b1 is the thickness of the display panel, and b2 is the thickness of the panel assembly.

[0012] In one embodiment, the step of providing the display panel assembly includes:

[0013] Provides a stacked display panel layer and a support film layer;

[0014] The display panel layer and the support film layer are cut into a plurality of independent panel assemblies. Each panel assembly includes a display panel and a support film stacked on top of each other, and at least one first electrode area, with the corresponding first electrode area located at the edge of the corresponding display panel. The angle α between the cut surface of the panel assembly and the second reference plane satisfies: 0°≤α≤10°. The second reference plane is perpendicular to the second direction.

[0015] In one embodiment, the step of providing the stacked display panel layer and the support film layer further includes:

[0016] Provides a support film layer and a display panel layer;

[0017] An adhesive layer is applied to one side of the support film layer, with the side of the support film layer with the adhesive layer facing the display panel layer, and the support film layer is aligned with the display panel layer.

[0018] The support film layer is pressed against the side of the display panel layer away from the display panel layer by a roller, so that the support film layer is adhered to the display panel layer;

[0019] A plurality of first electrodes are disposed on the display panel layer; the side of the display panel layer opposite to the supporting film layer has a plurality of first electrode regions, and at least one first electrode is disposed in the first electrode region.

[0020] In one embodiment, the step of providing the display panel assembly further includes:

[0021] After the panel assembly is formed, a conductive adhesive layer is disposed between the connection area of ​​the first electrode area and the second electrode area, and the first electrode of the first electrode area and the second electrode of the connection area are aligned.

[0022] A first preset pressure is applied to the panel assembly to make the first electrode area and the second electrode area initially contact each other through the conductive adhesive layer;

[0023] A second preset pressure is applied to the panel assembly, and the temperature of the display panel is increased, so that the first electrode in the first electrode area and the second electrode in the connection area are electrically connected through conductive particles in the conductive adhesive; wherein the second preset pressure is greater than the first preset pressure.

[0024] In one embodiment, the step of forming the colloid in the glue tank includes:

[0025] Apply adhesive to the adhesive tank and wait for a preset time t, where the preset time t satisfies: 5s≤t≤10s. Along the second direction, the dimension n of the adhesive extending beyond the exposed area satisfies 0.15mm≤n≤0.25mm.

[0026] According to another aspect of this application, a display module is provided, formed by bonding using the bonding method of the display module described in any of the above embodiments, the display module comprising:

[0027] A display panel assembly includes a panel assembly and a protective film stacked along a first direction, and a flexible circuit board disposed on the side of the panel assembly facing away from the protective film. The side of the panel assembly facing away from the protective film has a first electrode region. The flexible circuit board has a second electrode region, which includes a connection region connected to the first electrode region and an exposed region protruding from the panel assembly along a second direction. A groove is defined between the portion of the flexible circuit board where the exposed region is disposed and the side of the panel assembly along the second direction near the exposed region.

[0028] An colloid is disposed within the adhesive groove and adhered between the panel assembly and the location where the exposed area is situated on the flexible circuit board.

[0029] The display module of this application is bonded using the above-mentioned bonding method for display modules. It has an adhesive that can better cover the exposed area of ​​the flexible circuit board, thereby providing better protection for the second electrode area of ​​the flexible circuit board. Furthermore, the adhesive is placed in the adhesive groove, which reduces the risk of the protective film sticking to the adhesive and making it difficult to remove the protective film later.

[0030] In one embodiment, the colloid includes an extension that is bonded to a portion of the flexible circuit board outside the second electrode area, wherein the dimension n of the colloid extending beyond the exposed area along the second direction satisfies: 0.15mm ≤ n ≤ 0.25mm.

[0031] In one embodiment, the panel assembly includes a display panel and a support film stacked on top of each other, wherein along the first direction, the thickness b1 of the display panel satisfies: 0.03mm≤b1≤0.05mm; and the thickness b2 of the panel assembly satisfies: 0.09mm≤b2≤0.15mm.

[0032] In one embodiment, the panel assembly has a cut surface, and the angle α between the cut surface and the second reference plane satisfies: 0°≤α≤10°; wherein the second reference plane is perpendicular to the second direction. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of a display panel assembly with an adhesive material disposed on an inclined operating table in one embodiment of this application.

[0034] Figure 2 This is a flowchart illustrating a bonding method for a display module in one embodiment of this application.

[0035] Figure 3 for Figure 1 Enlarged view of point A in the middle.

[0036] Figure 4This is a comparison of the adhesion of the colloids.

[0037] Figure 5 for Figure 4 Enlarged view of point B in the middle.

[0038] Figure 6 This is a flowchart illustrating the process of providing a display panel assembly in one embodiment of this application.

[0039] Figure 7 This is a schematic diagram of the structure of the cutting panel assembly forming an inclined cutting surface in one embodiment of this application.

[0040] Figure 8 This is a schematic diagram of a panel assembly with an inclined cutting surface and a flexible circuit board with an adhesive applied to an inclined operating table in one embodiment of this application.

[0041] Figure 9 for Figure 8 A magnified view of point C in the middle.

[0042] Figure 10 This is a schematic diagram illustrating the process of bonding the first electrode region of the panel assembly and the second electrode region of the flexible circuit board in one embodiment of this application.

[0043] Explanation of icon numbers:

[0044] 1. Display panel; 2. Support film; 3. Protective film; 4. First electrode area; 5. Flexible circuit board; 6. Second electrode area; 7. Colloid; 8. Operating table; 9. Gap. Detailed Implementation

[0045] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0046] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0047] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0048] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0049] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0050] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0051] Flexible printed circuit boards (FPCs) and display panels are typically bonded together using adhesive layers. For example, conductive adhesive or anisotropic conductive adhesive film is placed between the pads of the FPC and the pads of the display panel. Through the conductivity of the conductive adhesive, the two are mechanically connected while maintaining electrical conductivity.

[0052] However, because the electrode size of flexible printed circuit boards (PCBs) is usually larger than that of the electrodes on the display panel, some electrodes on the PCBs are often exposed. In other words, the pads (PADs) on the PCBs may not be completely covered by the overlay due to design or manufacturing reasons, resulting in exposed conductive parts. These exposed parts require surface treatment to prevent oxidation, corrosion, or short circuits.

[0053] Related technologies typically utilize surface plating, such as electroless nickel plating and immersion gold plating on the exposed electrodes of flexible printed circuit boards, or direct tin plating on the exposed electrodes, to isolate the exposed electrodes from the external environment. However, this method is relatively complex to operate and provides poor isolation and protection for the electrodes.

[0054] Based on this, this application provides a bonding method for a display module and a display module, which can effectively protect the exposed electrodes of a flexible printed circuit board.

[0055] See Figure 1 , Figure 2 and Figure 3 As shown, Figure 1 This is a schematic diagram of the structure of a display panel assembly with colloid 7 disposed on an inclined operating table in one embodiment of this application. Figure 2 This is a flowchart illustrating a bonding method for a display module in one embodiment of this application. Figure 3 for Figure 1 Enlarged view of point A in the middle.

[0056] The bonding method for the display module provided in this application includes:

[0057] S1. Provide display panel components.

[0058] The display panel assembly includes a panel assembly and a protective film 3 stacked along a first direction, and a flexible circuit board 5 disposed on the side of the panel assembly opposite to the protective film 3. The main function of the protective film 3 is to provide physical protection for the panel assembly and prevent external scratches or contamination.

[0059] The panel assembly has a first electrode region 4 on the side facing away from the protective film 3, and the flexible circuit board 5 has a second electrode region 6. The panel assembly and the flexible circuit board 5 are electrically connected mainly through the connection between the first electrode region 4 and the second electrode region 6. The second electrode region 6 includes a connection area connected to the first electrode region 4 and an exposed area protruding from the panel assembly along a second direction. Specifically, it is connected to the first electrode region 4 on the side of the panel assembly facing away from the protective film 3 through the connection area, thus achieving electrical connection.

[0060] A groove is defined between the exposed area of ​​the flexible circuit board 5 and the side of the panel assembly near the exposed area along the second direction, for subsequent filling of the adhesive 7.

[0061] It is understandable that a portion of the same second electrode within the second electrode region 6 is located in the connection region, while the remaining portion is located in the exposed region.

[0062] S2. Rotate the display panel assembly about an axis parallel to a third direction, so that the angle between the display panel assembly and the first reference plane is an acute angle. The first direction, the second direction, and the third direction intersect each other. The first reference plane is perpendicular to the direction of gravity of the display panel assembly.

[0063] The acute angle between the display panel assembly and the first reference plane, and the fact that the first reference plane is perpendicular to the direction of gravity of the display panel assembly, help ensure that the colloid 7 can fully utilize gravity to flow during subsequent filling. By precisely controlling the tilt angle, the flow path of the colloid 7 can be effectively guided, preventing it from accidentally flowing into the area of ​​the protective film 3.

[0064] In this embodiment, the display panel assembly can be rotated about an axis parallel to a third direction using a mechanical device. For example, an operating table can be provided, and the display panel assembly can be placed on the operating table. The rotation of the operating table can drive the display panel assembly to rotate.

[0065] S3. Adhesive 7 is formed within the adhesive tank to bond the panel assembly and the flexible circuit board 5 together. Simultaneously, the tilted position of the display panel assembly allows the adhesive 7 to flow naturally under gravity and fill all gaps within the adhesive tank, enhancing protection for the second electrode area 6. In this embodiment, the adhesive 7 can be an insulating adhesive, such as a light-cured insulating resin adhesive, which is non-conductive to prevent the second electrode of the second electrode area 6 from being exposed. Furthermore, the use of insulating adhesive prevents the second electrode from being electrically connected to other external components through the adhesive 7.

[0066] In this embodiment, the adhesive 7 can be formed by dispensing. The fluidity of the adhesive 7 ensures that it can evenly cover the exposed area of ​​the flexible circuit board 5, forming a protective layer. By precisely setting the tilt angle of the display panel assembly, the flow range of the adhesive 7 can be precisely controlled, which helps to prevent the adhesive 7 from sticking to the protective film 3, making it inconvenient to remove the protective film 3 later. In some embodiments, the tilt angle of the operating table can be adjusted in real time. By flexibly adjusting its tilt angle, the flow range of the adhesive 7 can be precisely controlled, preventing it from spreading to the area of ​​the protective film 3, thereby reducing the risk of the adhesive 7 accidentally sticking to the protective film 3. No further limitations are imposed here.

[0067] See also Figure 3 , Figure 4 and Figure 5 As shown, Figure 4 This is a comparison of the adhesion of colloid 7. Figure 5 for Figure 4 Enlarged view at point B. During bonding, to prevent the pads of the flexible printed circuit board from being exposed or separating after bonding, the adhesive 7 is provided to protect them. It is understood that the horizontal dimension of the adhesive 7 needs to exceed the pads of the flexible printed circuit board, and the vertical dimension needs to not exceed the bottom surface of the top protective film 3, to prevent the protective film 3 from adhering and thus preventing its proper peeling. This application also achieves this step well.

[0068] However, in the actual manufacturing process, such as Figure 4 As shown, adhesive 7 is typically applied horizontally. However, due to limitations in nozzle size and manufacturing process precision, it's impossible to apply adhesive to the cut surface of the display panel 1 perfectly horizontally. This results in the adhesive 7 piling up at an offset position, making it difficult for the adhesive 7 to adhere to the cut surface of the display panel 1. (See reference...) Figure 5 As shown, this can lead to the displacement of the colloid 7 accumulation position and the exposure of the solder pads. There are gaps between the colloid 7 and the second electrode area 6, resulting in voids and uneven coating, and local exposure of the solder pad metal. This causes problems such as metal solder pad corrosion failure and abnormal module display during subsequent droplet reliability testing.

[0069] In the adhesive application process, conventional methods typically increase the amount of adhesive applied and improve application precision by adjusting the process flow, such as reducing the application speed, increasing the spraying pressure, and narrowing the dispensing distance. For example, while increasing the application speed and spraying pressure to increase the amount of adhesive applied, the goal is to move as much of the adhesive 7 as possible towards the cross-section of the display panel 1. However, because the cross-section of the display panel 1 is cut at an acute angle, such as... Figure 4Typically, due to the cutting technology of the display panel 1, the side of the display panel 1 closest to the flexible printed circuit board is tilted inward. This makes it very easy for the adhesive 7 to adhere to the top protective film 3, resulting in difficulty in peeling off the protective film 3. For example, reducing the dispensing spacing or increasing the number of dispensing passes can improve the coating accuracy, but with the increase in the number of dispensing passes, the instability of dispensing also increases, and the risk of dispensing failure also increases. It is evident that conventional methods have high requirements for the manufacturing process, and this operation is unstable, resulting in more defective products, and most often failing to achieve the intended effect.

[0070] The bonding method for the display module described in this application tilts the display panel assembly, utilizing gravity to optimize the filling process of the colloid 7. The colloid 7, placed within the adhesive tank, can flow and fill the gaps within the tank under gravity. The colloid 7 can flow effectively to various positions within the tank, facilitating complete coverage of exposed areas and improving protection. Furthermore, by setting a precise tilt angle for the display panel assembly, the above-mentioned arrangement can prevent the colloid 7 from flowing onto the protective film 3, reducing the risk of the colloid 7 adhering to the protective film 3. As can be seen, the bonding method for the display module of this application not only forms a colloid 7 with a suitable shape and specifications, allowing the colloid 7 to completely cover the exposed area of ​​the second electrode region 6 of the flexible circuit board 5 and provide reliable electrical protection, but also minimizes the risk of the colloid 7 accidentally adhering to the protective film 3 by setting the angle, thereby reducing the risk of damage when the protective film 3 is subsequently removed. In other words, the bonding method for the display module of this application achieves precise control over the shape and specifications of the colloid 7, effectively protecting the electrode area of ​​the flexible circuit board 5 and improving the manufacturing yield of the display module. It also has the advantages of simplified production process and reduced manufacturing costs.

[0071] In some embodiments, continue reading Figure 1 As shown, the panel assembly includes a display panel 1 and a support film 2 stacked on top of each other. The display panel 1, as the core component, is mainly responsible for the image display function. It generates and displays images through technologies such as its internal pixel array, backlight module, or organic light-emitting diode (OLED). The support film 2 is mainly used to provide mechanical support and structural stability for the display panel 1, preventing the display panel 1 from being damaged by external mechanical stress (such as bending, vibration, or impact) during manufacturing or use, while also enhancing the overall rigidity of the display module.

[0072] The protective film 3 is located on the side of the support film 2 facing away from the display panel 1. The protective film 3 is a protective film layer structure set on the support film 2, primarily providing physical protection for the support film 2 during the manufacturing and transportation of the display module, preventing damage to the display module from dust, scratches, chemical contamination, or other external factors. After the display module is manufactured and needed, the protective film 3 is removed.

[0073] Step S2, rotating the display panel assembly about an axis parallel to a third direction to set an acute angle between the display panel assembly and the first reference plane, includes:

[0074] The display panel assembly is placed on the operating table, which is then rotated about an axis parallel to a third direction to rotate the display panel assembly. This rotation of the operating table, which in turn rotates the display panel assembly, provides mechanical support, improves its stability, and reduces the risk of damage caused by external mechanical stress during operation.

[0075] The tilt angle r between the display panel assembly and the first reference plane satisfies: b1 / (m+0.5) < tan(r) < b2 / (m+0.5). Here, m is the length of the exposed area protruding beyond the display panel 1 along the second direction, b1 is the thickness of the display panel 1, and b2 is the thickness of the panel assembly. Satisfying this range allows different display panel assemblies to correspond to different tilt angles. In other words, the tilt angle r between the display panel assembly and the first reference plane can be adjusted according to the specific geometric dimensions of the display module, such as the length of the exposed area protruding beyond the display panel 1, the thickness of the display panel 1, and the thickness of the panel assembly. This facilitates better colloid 7 filling effects for display modules of different specifications.

[0076] By precisely designing the tilt angle r, display modules with different geometric dimensions are positioned at different tilt angles, allowing the colloid 7 to flow naturally under gravity and evenly fill all gaps within the adhesive groove. This flow characteristic ensures that the colloid 7 completely covers the exposed area of ​​the flexible circuit board 5. Furthermore, the precise angle design effectively prevents the colloid 7 from spreading to the protective film 3 area, significantly reducing the probability of the colloid 7 accidentally adhering to the protective film 3. It is understandable that if the colloid 7 spreads to the protective film 3 area and adheres to it, subsequent removal of the protective film 3 will not only be difficult but may also result in the removal of the colloid 7 or part of it, leading to a decrease in the adhesive strength of the colloid 7 and affecting its protective effect on the electrodes of the exposed area of ​​the flexible circuit board 5. Therefore, minimizing the adhesion of the colloid 7 to the protective film 3 is crucial.

[0077] Furthermore, in some embodiments, the operating table can be configured to adjust its tilt angle in real time while meeting the above-mentioned range, so as to reduce the risk of the colloid 7 sticking to the protective film 3 and improve the manufacturing yield of the display module. Specifically, the flow of the colloid 7 can be monitored by setting a monitor or by manual monitoring in order to adjust its tilt angle. No further restrictions are imposed here.

[0078] In some embodiments, when the thickness b1 of the display panel 1 is 0.03 mm, the thickness b2 of the panel assembly is 0.13 mm, and the length m of the exposed area protruding outside the display panel 1 is 0.2 mm, 0.043 < tan(r) < 0.186, corresponding to a tilt angle of 2.46° < r < 10.54°.

[0079] In some embodiments, see Figure 6 As shown, Figure 6 This is a schematic flowchart illustrating the provision of a display panel assembly in one embodiment of this application. Step S1, the step of providing the display panel assembly, includes the following: improving production efficiency by optimizing the cutting process and design details, facilitating the flow and filling of the colloid 7, and facilitating the alignment and connection of the first electrode region 4 and the second electrode region 6.

[0080] Step S1 specifically includes:

[0081] S11. A display panel layer and a support film layer are provided in a stacked configuration. Here, the display panel layer and the support film layer are stacked, meaning that they are already connected to each other. This enhances the overall structural stability of the display panel layer and the support film layer, effectively reduces defects caused by interlayer separation or misalignment, and improves the reliability of the display panel layer and the support film layer.

[0082] S12. The display panel layer and support film layer are cut into multiple independent panel assemblies. That is, the panel assemblies are formed by cutting large pieces of display panel layer and support film layer, which is conducive to mass production. Multiple panel assemblies can be produced simultaneously in a single production process, thereby reducing unit production cost. It also facilitates unified quality control, ensuring the consistency of performance and specifications of each panel assembly, and further improving product yield.

[0083] The panel assembly formed by cutting includes a display panel 1 and a support film 2 stacked on top of each other, and at least one first electrode region 4. The specific number of first electrode regions 4 and the number of first electrodes in each first electrode region 4 can be set according to actual application requirements, and no further restrictions are imposed here.

[0084] Furthermore, the corresponding first electrode area 4 is located at the edge of the corresponding display panel 1. This facilitates the electrical connection between the first electrode area 4 and the second electrode area 6 of the flexible circuit board 5, ensuring the stability and reliability of signal transmission. This edge layout also reduces interference from the electrode area to the display area, improving the optical performance of the display module.

[0085] See Figure 7 As shown, Figure 7This is a schematic diagram illustrating the structure of a panel assembly cut to form an inclined cut surface in one embodiment of this application. During cutting, the angle α between the cut surface of the panel assembly and the second reference plane satisfies: 0°≤α≤11°, where the second reference plane is perpendicular to the second direction. The angle α can also be understood as the inclination angle of the cut surface. Further, during cutting, the angle α between the cut surface of the panel assembly and the second reference plane satisfies: 0°≤α≤10°.

[0086] The cutting plane must satisfy the range 0° ≤ α, ensuring it is at least parallel to the second reference plane. In this case, the cutting plane is parallel to the thickness direction of the panel assembly. It is understandable that the cutting of panel assemblies in related technologies is typically influenced by the cutting process, resulting in... Figure 4 The display panel 1 in the previous design has an inwardly tilted cut surface near the flexible printed circuit board, which makes it easy for the adhesive 7 to stick to the protective film 3 during dispensing. However, this application addresses this issue by making the cut surface at least vertical, or perpendicular to the display panel 1, thus reducing the risk of the adhesive 7 sticking to the protective film 3 during dispensing.

[0087] See Figure 7 , Figure 8 and Figure 9 As shown, and satisfying the range of α≤10°, it can effectively prevent the cutting angle from being too large, which would cause the size of the cutting surface along the second direction to be too wide, resulting in increased cutting energy requirements during cutting, increased heat-affected zone, and increased impact on the internal structural stability of the display panel 1. Therefore, satisfying the above range can facilitate the formation of a suitable colloid 7 while maintaining the internal structural stability of the display panel 1 and improving the display effect of the display module.

[0088] It should be noted that the cut surface is the side surface formed when cutting the stacked display panel layer and support film layer to separate adjacent panel components. This cut surface can be formed by laser cutting, using a laser to cut from the support film layer in the direction of the display panel layer, and tilting the cut surface.

[0089] It can be understood that a protective film layer is provided on the side of the support film layer that is away from the display panel layer. When cutting, the protective film layer, the support film layer and the display panel layer are cut together, and the protective film layer is cut to form the protective film 3.

[0090] In some embodiments, see Figure 6 As shown, step S11, providing the stacked display panel layer and support film layer, includes:

[0091] S111. Provides a support film layer and a display panel layer. The support film layer and display panel layer provided here are not connected to each other. The most suitable material can be selected according to specific application requirements, which will not be elaborated further here.

[0092] S112. Apply an adhesive layer to one side of the support film layer, with the adhesive-coated side of the support film layer facing the display panel layer, and align the support film layer with the display panel layer. The applied adhesive layer can be an anisotropic conductive film (ACF), or at least one of isotropic conductive adhesive (ICA), anisotropic conductive adhesive (ACA), silver powder conductive adhesive, copper powder conductive adhesive, silver-plated copper powder conductive adhesive, and carbon-based conductive adhesive, etc., without further restrictions.

[0093] S113. The support film layer is rolled against the side of the display panel layer by rollers, so that the support film layer is bonded to the display panel layer. This helps to ensure a tight bond between the support film layer and the display panel layer, eliminates air bubbles or gaps between layers, and improves the mechanical strength and electrical connection stability between layers.

[0094] S114. Multiple first electrodes are disposed on the display panel layer. The side of the display panel layer opposite to the support film layer has multiple first electrode regions 4, and at least one first electrode is disposed in the first electrode region 4. This improves the flexibility of electrical connection design. The multiple first electrodes can ensure the stability of signal transmission, especially in high-resolution and high-refresh-rate display applications, which can effectively reduce signal loss and interference.

[0095] In some embodiments, see Figure 10 As shown, Figure 10 This is a schematic diagram illustrating the process of bonding the first electrode region of the panel assembly and the second electrode region of the flexible circuit board in one embodiment of this application.

[0096] Step S1, providing the display panel assembly also includes:

[0097] S13. After forming the panel assembly, a conductive adhesive layer is applied between the connection area of ​​the first electrode area 4 and the second electrode area 6, and the first electrode of the first electrode area 4 and the second electrode of the connection area are aligned. It is important to ensure accurate alignment between the first and second electrodes to avoid poor electrical connection or short circuits caused by inaccurate alignment.

[0098] S14. Apply a first preset pressure to the panel assembly to make the first electrode area 4 and the second electrode area 6 initially contact each other through the conductive adhesive layer. By applying the first preset pressure, the initial contact between the electrodes is achieved, which helps to improve the alignment accuracy between the electrodes and lays the foundation for subsequent curing and final connection.

[0099] S15. Apply a second preset pressure to the panel assembly and raise the temperature of the display panel 1 so that the first electrode of the first electrode area 4 and the second electrode of the connection area are electrically connected through conductive particles in the conductive adhesive; wherein the second preset pressure is greater than the first preset pressure. The greater pressure and appropriate temperature help the conductive particles to be evenly distributed between the electrodes, ensuring the uniformity and reliability of the electrical connection.

[0100] In some embodiments, step S3, forming colloid 7 in the glue tank, includes:

[0101] Apply adhesive to the glue tank and wait for a preset time t, which satisfies the condition: 5s ≤ t ≤ 10s. Along the second direction, the dimension n of the adhesive 7 extending beyond the exposed area satisfies 0.15mm ≤ n ≤ 0.25mm. This preset waiting time allows the adhesive 7 to evenly fill all gaps in the glue tank, preventing premature curing and thus avoiding incomplete filling due to premature curing. It also ensures that the adhesive 7 forms a stable bond after curing, preventing differences in bond strength caused by uneven distribution of the adhesive 7.

[0102] The size n of the colloid 7 exceeding the exposed area meets the above range. By precisely controlling the size of the colloid 7 exceeding the exposed area, the colloid 7 can completely cover the exposed area, which helps to enhance the protection of the exposed area and provide reliable electrical protection, while not exceeding the size too much and affecting the structure of the flexible circuit board 5 itself.

[0103] It should be noted that after dispensing the adhesive and waiting for a preset time t to form a suitable colloid 7, the colloid needs to be cured, such as by using a light curing device.

[0104] In some embodiments, along the second direction, the length m of the exposed area protruding outside the display panel 1 satisfies: 0.15mm ≤ m ≤ 0.25mm. Satisfying the above range is beneficial for the second electrode area 6 of the flexible circuit board 5 to have a suitable size range, for the flexible circuit board 5 to use different models of display panels 1, for the second electrode area 6 of the flexible circuit board 5 to be adapted to the first electrode area 4 of different models of display panels 1, and for providing sufficient space to ensure a stable and reliable electrical connection between the first electrode area 4 and the second electrode area 6, thereby reducing signal loss and interference.

[0105] In some embodiments, the operating table includes a support surface for supporting the display panel assembly, and the support surface is provided with a plurality of vacuum adsorption holes, which are connected to a vacuum device. Before the step of rotating the operating table about an axis parallel to a third direction, the vacuum device is activated, and the display panel assembly and flexible circuit board 5 are adsorbed on the support surface through the vacuum adsorption holes. This prevents the display panel assembly on the operating table from slipping due to gravity during tilting, thus improving the stability of the display panel assembly during operation. Furthermore, the vacuum adsorption system can complete the fixing and releasing of the assembly in a short time, significantly shortening the clamping and disassembly time and improving overall production efficiency.

[0106] refer to Figure 1 As shown, this application also provides a display module, formed by bonding using the bonding method of the display module in any of the above embodiments. The display module includes a display panel assembly and an adhesive 7. The display panel assembly includes a panel assembly and a protective film 3 stacked along a first direction, and a flexible circuit board 5 disposed on the side of the panel assembly facing away from the protective film 3. The side of the panel assembly facing away from the protective film 3 has a first electrode region 4. The flexible circuit board 5 has a second electrode region 6 for electrically connecting with the first electrode region 4 of the display panel assembly.

[0107] The second electrode region 6 of the flexible circuit board 5 includes a connection region connected to the first electrode region 4, and an exposed region protruding from the panel assembly along a second direction. A groove for accommodating adhesive 7 is defined between the portion of the flexible circuit board 5 where the exposed region is located and the side of the panel assembly along the second direction near the exposed region.

[0108] The adhesive 7 is disposed within the adhesive tank and adheres to the exposed area between the panel assembly and the flexible circuit board 5. The adhesive 7 strengthens the bond between the display panel assembly and the flexible circuit board 5, making the connection more stable and reliable. Simultaneously, the adhesive 7 enhances the protection of the second electrode area 6, reducing the risk of corrosion failure of the metal pads. In this embodiment, the adhesive 7 can be an insulating adhesive, such as a light-cured insulating resin adhesive, protecting the second electrode area 6 while preventing the second electrode from being electrically connected to other external components through the adhesive 7.

[0109] The display module of this application is bonded using the above-mentioned bonding method for display modules. It has an adhesive 7 that can better cover the exposed area of ​​the flexible circuit board 5, thereby providing better protection for the second electrode area 6 of the flexible circuit board 5. Furthermore, the adhesive 7 is placed in the adhesive groove, which reduces the risk of the protective film 3 sticking to the adhesive and making it difficult to remove the protective film 3 later.

[0110] In some embodiments, continue reading Figure 1The colloid 7 includes an extension portion that adheres to the portion of the flexible circuit board 5 outside the area where the second electrode region 6 is located. This allows the colloid 7 to completely cover the exposed area and to adhere between the flexible circuit board 5 and the display panel assembly, thereby enhancing the stability and reliability of the connection between the flexible circuit board 5 and the display panel assembly.

[0111] Along the second direction, the dimension n of the colloid 7 extending beyond the exposed area satisfies: 0.15mm ≤ n ≤ 0.25mm. Since the dimension n of the colloid 7 extending beyond the exposed area satisfies the above range, by precisely controlling the extension dimension of the colloid 7, the colloid 7 can completely cover the exposed area, which helps to enhance the protection of the exposed area, provides reliable electrical protection, and at the same time, does not exceed the size too much, thus not affecting the structure of the flexible circuit board 5 itself.

[0112] In some embodiments, continue reading Figure 1 Along the first direction, the thickness b1 of the display panel 1 satisfies: 0.03mm ≤ b1 ≤ 0.05mm. Meeting this range facilitates a thinner display panel 1, helping to reduce the weight of the display module and making it more suitable for devices requiring a slim and lightweight design, such as smartphones, tablets, and laptops. Simultaneously, it contributes to better optical performance, such as higher light transmittance and clearer display effects.

[0113] The thickness b2 of the panel assembly satisfies the following condition: 0.09mm ≤ b2 ≤ 0.15mm. Meeting this range helps improve the mechanical strength and stability of the entire display module. This thickness range effectively prevents damage to the display module from external mechanical stresses (such as bending, vibration, or impact) during manufacturing and use. At the same time, the optimized thickness range of the panel assembly ensures sufficient mechanical strength while avoiding increased weight and cost due to excessive thickness.

[0114] Meanwhile, when the conductive adhesive is filled between the display panel 1 and the flexible circuit board 5 of the panel assembly, the display panel 1 and the panel assembly that meet the above range are provided with a good match. This facilitates the uniform distribution of the conductive adhesive between the two, helps to form a stable adhesive layer, and improves the bonding stability between the display panel 1 and the flexible circuit board 5.

[0115] In some embodiments, the panel assembly has a cut surface, and the included angle α between the cut surface and the second reference plane satisfies: 0°≤α≤10°, wherein the second reference plane is perpendicular to the second direction.

[0116] Compared to the cutting process in related technologies Figure 4The display panel 1 shown has an inwardly tilted cut surface near the flexible printed circuit board, which makes it easy for the adhesive 7 to stick to the protective film 3 during dispensing. This satisfies the range of 0°≤α, ensuring that the cut surface is at least parallel to the second reference plane and that the cut surface is at least vertically set, or perpendicular to the display panel 1. This reduces the risk of the adhesive 7 sticking to the protective film 3 during dispensing and causing adhesion to the protective film 3.

[0117] Furthermore, satisfying the range of α≤10° can effectively prevent the cutting angle from being too large, which would cause the size of the cutting surface along the second direction to be too wide, resulting in an increase in the required cutting energy during cutting, an increase in the heat-affected zone, and an increase in the impact on the internal structural stability of the display panel 1.

[0118] Therefore, by satisfying the above range, it is possible to maintain the internal structural stability of the display panel 1 while facilitating the formation of a suitable colloid 7, thereby improving the display effect of the display module.

[0119] The bonding method and display module of this application involve tilting the display panel assembly during the manufacturing process to optimize the filling process of the colloid 7 using gravity. The colloid 7, placed within the colloid tank, flows and fills the gaps under gravity, allowing it to flow effectively to various locations within the tank. This ensures complete coverage of the exposed areas, improving protection. Simultaneously, it minimizes the risk of the colloid 7 adhering to the protective film 3. Therefore, the display module manufactured using the bonding method of this application not only forms a colloid 7 with a suitable shape and specifications, enabling it to completely cover the exposed area of ​​the second electrode region 6 of the flexible circuit board 5 and provide reliable electrical protection, but also minimizes the risk of the colloid 7 accidentally adhering to the protective film 3 by adjusting the angle, thus reducing the risk of damage during subsequent removal of the protective film 3. In other words, the bonding method of this application achieves precise control over the shape and specifications of the colloid 7, effectively protecting the electrode area of ​​the flexible circuit board 5 and improving the manufacturing yield of the display module. It also has the advantages of simplified production process and reduced production costs.

[0120] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0121] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A bonding method for a display module, characterized in that, The bonding method of the display module includes: A display panel assembly is provided; the display panel assembly includes a panel assembly and a protective film stacked along a first direction, and a flexible circuit board disposed on the side of the panel assembly opposite to the protective film, the side of the panel assembly opposite to the protective film having a first electrode area, the flexible circuit board having a second electrode area, the second electrode area including a connection area connected to the first electrode area, and an exposed area protruding from the panel assembly along a second direction; a groove is defined between the portion of the flexible circuit board where the exposed area is disposed and the side of the panel assembly along the second direction near the exposed area; The display panel assembly is rotated about an axis parallel to a third direction, such that the angle between the display panel assembly and the first reference plane is an acute angle; wherein the first direction, the second direction, and the third direction intersect each other; the first reference plane is perpendicular to the direction of gravity of the display panel assembly; An adhesive is formed in the adhesive tank to bond the panel assembly and the flexible circuit board together.

2. The bonding method for a display module according to claim 1, characterized in that, The panel assembly includes a display panel and a support film stacked on top of each other, the protective film being located on the side of the support film facing away from the display panel; the step of rotating the display panel assembly about an axis parallel to a third direction so that the angle between the display panel assembly and the first reference plane is set at an acute angle includes: The display panel assembly is placed on an operating table, and the operating table is rotated about an axis parallel to the third direction to drive the display panel assembly to rotate. The tilt angle r between the display panel assembly and the first reference plane satisfies: b1 / (m+0.5)<tan(r)<b2 / (m+0.5); where m is the length of the exposed area protruding from the display panel along the second direction, b1 is the thickness of the display panel, and b2 is the thickness of the panel assembly.

3. The bonding method for a display module according to claim 1, characterized in that, The step of providing the display panel assembly includes: Provides a stacked display panel layer and a support film layer; The display panel layer and the support film layer are cut into a plurality of independent panel assemblies. Each panel assembly includes a display panel and a support film stacked on top of each other, and at least one first electrode area, with the corresponding first electrode area located at the edge of the corresponding display panel. The angle α between the cut surface of the panel assembly and the second reference plane satisfies: 0°≤α≤10°. The second reference plane is perpendicular to the second direction.

4. The bonding method for a display module according to claim 3, characterized in that, The step of providing the stacked display panel layer and support film layer includes: Provides a support film layer and a display panel layer; An adhesive layer is applied to one side of the support film layer, with the side of the support film layer with the adhesive layer facing the display panel layer, and the support film layer is aligned with the display panel layer. The support film layer is pressed against the side of the display panel layer away from the display panel layer by a roller, so that the support film layer is adhered to the display panel layer; A plurality of first electrodes are disposed on the display panel layer; the side of the display panel layer opposite to the supporting film layer has a plurality of first electrode regions, and at least one first electrode is disposed in the first electrode region.

5. The bonding method for a display module according to claim 3, characterized in that, The step of providing the display panel assembly further includes: After the panel assembly is formed, a conductive adhesive layer is disposed between the connection area of ​​the first electrode area and the second electrode area, and the first electrode of the first electrode area and the second electrode of the connection area are aligned. A first preset pressure is applied to the panel assembly to make the first electrode area and the second electrode area initially contact each other through the conductive adhesive layer; A second preset pressure is applied to the panel assembly, and the temperature of the display panel is increased, so that the first electrode in the first electrode area and the second electrode in the connection area are electrically connected through conductive particles in the conductive adhesive; wherein the second preset pressure is greater than the first preset pressure.

6. The bonding method for a display module according to claim 1, characterized in that, The step of forming the colloid in the glue tank includes: Apply adhesive to the adhesive tank and wait for a preset time t, where the preset time t satisfies: 5s≤t≤10s. Along the second direction, the dimension n of the adhesive extending beyond the exposed area satisfies 0.15mm≤n≤0.25mm.

7. A display module, characterized in that, The display module is formed by bonding using the bonding method of any one of claims 1 to 6, wherein the display module comprises: A display panel assembly includes a panel assembly and a protective film stacked along a first direction, and a flexible circuit board disposed on the side of the panel assembly facing away from the protective film. The side of the panel assembly facing away from the protective film has a first electrode region. The flexible circuit board has a second electrode region, which includes a connection region connected to the first electrode region and an exposed region protruding from the panel assembly along a second direction. A groove is defined between the portion of the flexible circuit board where the exposed region is disposed and the side of the panel assembly along the second direction near the exposed region. An colloid is disposed within the adhesive groove and adhered between the panel assembly and the location where the exposed area is situated on the flexible circuit board.

8. The display module according to claim 7, characterized in that, The colloid includes an extension portion, which is bonded to the portion of the flexible circuit board outside the second electrode area. Along the second direction, the dimension n of the colloid extending beyond the exposed area satisfies: 0.15mm ≤ n ≤ 0.25mm.

9. The display module according to claim 8, characterized in that, The panel assembly includes a display panel and a support film stacked on top of each other. Along the first direction, the thickness b1 of the display panel satisfies: 0.03mm≤b1≤0.05mm; the thickness b2 of the panel assembly satisfies: 0.09mm≤b2≤0.15mm.

10. The display module according to claim 7, characterized in that, The panel assembly has a cut surface, and the included angle α between the cut surface and the second reference plane satisfies: 0°≤α≤10°; wherein the second reference plane is perpendicular to the second direction.

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