Flexible circuit board, display module and display device

Abstract

The utility model relates to a flexible circuit board, which comprises a flexible circuit board body, a wrapping part and an insulating protective layer, and a first accommodating cavity is formed among the wrapping part, the insulating protective layer and the flexible circuit board body. When a corrosion medium permeates into the edge of the flexible circuit board, the corrosion medium flows into the first accommodating cavity along the space between the insulating protection layer and the flexible circuit board body, and the surface, far away from the component, of the wrapping part can block the corrosion medium. A corrosion medium is prevented from corroding a bonding pad of a component and a connecting layer between the bonding pad and the welding surface of the flexible circuit board body, and poor conduction of the flexible circuit board is prevented. The utility model also provides a display module comprising the flexible circuit board, and a display device comprising the display module.

Description

TECHNICAL FIELD

[0001] The utility model relates to display technical field, specifically, relate to a kind of flexible circuit board, display module and display device. BACKGROUND

[0002] Under the trend of the overall thinning of display device, the internal space utilization of display device is more extreme, and the components on the flexible circuit board are the thickest position in the display module. Thinning this area will affect the corrosion resistance of the flexible circuit board.

[0003] In order to thin the thickness of the display device, the wrapping part is arranged to cover only the welding position of the component and the circuit board. The corrosion medium enters the interface between the wrapping part and the component from the upper surface of the component, corrodes the connecting layer of the welding position of the component and the flexible circuit board, and causes the conduction failure of the flexible circuit board.

[0004] It should be noted that the information of the above background art part of the utility model is only used to strengthen the understanding of the background of the utility model, and therefore can include information that does not constitute prior art known to those skilled in the art. UTILITY MODEL CONTENT

[0005] The utility model aims to solve the problem of corrosion of the corrosion medium to the welding position of the component and the circuit board, and to provide a flexible circuit board, a display module and a display device.

[0006] According to one aspect of the utility model, a flexible circuit board is provided, which comprises a flexible circuit board body, a component, a connecting layer, a wrapping part and an insulating protective layer. The flexible circuit board body has a welding surface. The component is arranged on the welding surface of the flexible circuit board. The component comprises a component body and a solder pad. The solder pad is arranged on the periphery of the component body. The connecting layer connects the welding surface of the flexible circuit board and the solder pad. The wrapping part is arranged on the side of the connecting layer and the solder pad away from the component body. The insulating protective layer covers the welding surface, the side of the wrapping part away from the flexible circuit board body, and the side of the component away from the flexible circuit board body. The wrapping part, the insulating protective layer and the flexible circuit board body form a first accommodating cavity.

[0007] In one embodiment of the utility model, the side of the wrapping part away from the component comprises a first blocking surface. One end of the first blocking surface is attached to the welding surface, and the other end is close to the insulating protective layer. The distance between the first blocking surface and the side of the solder pad away from the component body is the first size of the wrapping part. The first size of the wrapping part gradually increases in the direction away from the flexible circuit board body.

[0008] In one embodiment of the utility model, the first blocking surface is an arc-shaped surface recessed towards the component body.

[0009] In one embodiment of the utility model, the one side of the wrapping part away from the flexible circuit board body is a supporting surface, the distance between the supporting surface and the welding surface is a second size, when the maximum first size of the wrapping part is greater than the second size, the shape of the first blocking surface is an elliptical arc surface.

[0010] In one embodiment of the utility model, the one side of the wrapping part away from the flexible circuit board body is a supporting surface, the distance between the supporting surface and the welding surface is a second size, when the maximum first size of the wrapping part is greater than the second size, the shape of the first blocking surface is an elliptical arc surface.

[0011] In one embodiment of the utility model, the angle between the tangent of the one side of the first blocking surface away from the flexible circuit board body and the welding surface of the flexible circuit board is greater than 0 degrees and less than 90 degrees.

[0012] In one embodiment of the utility model, the first blocking surface is an inclined surface, the increasing rate of the first size of the wrapping part is same along the direction away from the flexible circuit board body, the angle between the first blocking surface and the one side of the pad away from the component body is less than 90 degrees.

[0013] In one embodiment of the utility model, the sectional area of the first accommodating cavity is:

[0014] S > C2 * △L * H / C1;

[0015] Wherein, C1 is the perimeter of the device area of the welding surface, C2 is the length of the edge of the insulation protective layer, △L is the absorption volume per unit length of the insulation protective layer, and H is the water absorption time.

[0016] In one embodiment of the utility model, the one side of the wrapping part away from the component further comprises a second blocking surface, the second blocking surface is connected to the other end of the first blocking surface, and the angle between the second blocking surface and the one side of the pad away from the component body is -5-5 degrees.

[0017] In one embodiment of the utility model, the second size of the wrapping part gradually increases along the direction close to the component body.

[0018] In one embodiment of the utility model, the supporting surface is an arc surface convex to the direction away from the flexible circuit board body.

[0019] In one embodiment of the utility model, the one side of the wrapping part away from the flexible circuit board body is lower than the one side of the pad away from the flexible circuit board body.

[0020] According to another aspect of the utility model, a display module is provided, which comprises the flexible circuit board provided by one aspect of the utility model.

[0021] In an embodiment of the utility model, display module still includes middle frame and flexible spacer, and the welding surface includes device area, and the component is arranged in device area, and the flexible spacer is interference fit between middle frame and flexible circuit board body, and the flexible spacer is located at the periphery of device area.

[0022] In an embodiment of the utility model, display module still includes protective layer and display layer, and the protective layer is arranged on the side of flexible circuit board body far from the insulating protective layer, and the display layer is arranged on the side of the protective layer far from the flexible circuit board body.

[0023] In an embodiment of the utility model, the thickness of flexible spacer needs to satisfy the following formula:

[0024] (H-δ) x E x S < F;

[0025] H is the thickness of flexible spacer before assembly, δ is the gap between flexible circuit board and middle frame, E is the elastic modulus of flexible spacer, the contact area of flexible spacer and flexible circuit board is S, and the display layer can bear the maximum force F.

[0026] According to another aspect of the utility model, a display device is provided, which comprises the display module provided in any one of the other aspects of the utility model.

[0027] The flexible circuit board comprises a flexible circuit board body, a wrapping part and an insulating protective layer, and the wrapping part and the insulating protective layer form a first accommodating cavity with the flexible circuit board body. When the edge of the flexible circuit board penetrates into a corrosive medium, the corrosive medium flows along the insulating protective layer and the flexible circuit board body into the first accommodating cavity, and the side of the wrapping part far from the component can block the corrosive medium, so that the corrosive medium cannot corrode the solder pad of the component and the connecting layer between the solder pad and the welding surface of the flexible circuit board body, and the conduction failure of the flexible circuit board is prevented.

[0028] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and cannot limit the utility model. BRIEF DESCRIPTION OF DRAWINGS

[0029] The drawings incorporated into the description and forming part of the description show embodiments consistent with the utility model, and together with the description are used to explain the principles of the utility model. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained according to the drawings without creative labor for those skilled in the art.

[0030] Figure 1 When the wrapping part wraps the whole component completely, the cross-sectional schematic view of the display module related to the embodiments of the utility model is shown.

[0031] Figure 2 For the wrapping part to wrap the entire component completely, the partial cross-sectional view of the display module is shown in the embodiment of the utility model.

[0032] Figure 3 For the wrapping part to cover only the side of the pad away from the component body, the pad and the connecting layer between the pad and the welding surface, the cross-sectional view of the display module is shown in the embodiment of the utility model.

[0033] Figure 4 For the wrapping part to cover only the side of the pad away from the component body, the pad and the connecting layer between the pad and the welding surface, the partial cross-sectional view of the display module is shown in the embodiment of the utility model.

[0034] Figure 5 For the wrapping part to cover only the side of the pad away from the component body, the pad and the connecting layer between the pad and the welding surface, the intrusion path of the corrosive medium is shown in the embodiment of the utility model.

[0035] Figure 6 For the wrapping part, the insulating protective layer and the flexible circuit board body to form the first accommodating cavity, the cross-sectional view of the display module is shown in the embodiment of the utility model.

[0036] Figure 7 For the wrapping part, the insulating protective layer and the flexible circuit board body to form the first accommodating cavity, the partial cross-sectional view of the display module is shown in the embodiment of the utility model.

[0037] Figure 8 For the wrapping part, the insulating protective layer and the flexible circuit board body to form the first accommodating cavity, the partial three-dimensional structure view of the display module is shown in the embodiment of the utility model.

[0038] Figure 9 For the wrapping part, the insulating protective layer and the flexible circuit board body to form the first accommodating cavity, the exploded view of the insulating protective layer and the rest of the flexible circuit board is shown in the embodiment of the utility model.

[0039] Figure 10 For the wrapping part, the insulating protective layer and the flexible circuit board body to form the first accommodating cavity, the intrusion path of the corrosive medium is shown in the embodiment of the utility model.

[0040] Figure 11 For the shape of the first blocking surface to be a circular arc surface, the partial cross-sectional view of the display module is shown in the embodiment of the utility model.

[0041] Figure 12 For the shape of the first blocking surface to be an elliptical arc surface, the partial cross-sectional view of the display module is shown in the embodiment of the utility model.

[0042] Figure 13 For the first blocking surface is inclined surface, the utility model discloses a partial cross section schematic view of display module.

[0043] Figure 14 For the support surface of the wrapping part is inclined plane, the utility model discloses a partial cross section schematic view of display module.

[0044] Figure 15 For the support surface of the wrapping part is the arc surface that protrude to the direction away from the flexible circuit board body, the utility model discloses a partial cross section schematic view of display module.

[0045] Figure 16 For two submodules to close and enclose the forming opening, the utility model discloses a three -dimensional structure schematic view when the mold is cooperated with the flexible circuit board.

[0046] Figure 17 For two submodules to close and enclose the forming opening, the utility model discloses a cross section schematic view when the mold is cooperated with the flexible circuit board.

[0047] Figure 18 For two submodules to separate, the utility model discloses a three -dimensional structure schematic view when the flexible circuit board is cooperated.

[0048] Figure 19 For two submodules to separate, the utility model discloses a cross section schematic view of the flexible circuit board.

[0049] Figure 20 For the flexible spacer part to be interference fit between the middle frame and the flexible circuit board body, the utility model discloses a cross section schematic view of display module.

[0050] Figure 21 For the flexible spacer part to be interference fit between the middle frame and the flexible circuit board body, the utility model discloses a plane schematic view of display module.

[0051] Figure 22 For the flexible spacer part to be separated from the flexible circuit board and the middle frame from the periphery of the device area, the utility model discloses a cross section schematic view of display module.

[0052] Figure 23 For the flexible spacer part to be set on the periphery of the insulating protective layer, the utility model discloses a cross section schematic view of display module.

[0053] In the diagram: 1-Flexible circuit board, 11-Flexible circuit board body, 111-Soldering surface, 1111-Component area, 1112-Peripheral area, 1113-Fingerprint opening, 12-Component, 121-Component body, 122-Solder pad, 13-Connection layer, 14-Wrapping section, 141-First blocking surface, 142-Second blocking surface, 143-Supporting surface, 15-Insulating protective layer, 151-First transition section, 152-Second... Transition section, 153-attachment protrusion, 154-through hole, 16-first receiving cavity, 17-second receiving cavity, 2-protective layer, 3-display layer, 4-polarizer, 5-optical adhesive layer, 6-cover plate, 7-heat dissipation layer, 8-middle frame, 81-bottom, 82-side, 821-mounting groove, 9-flexible spacer, 10-mold, 101-sub-module, 102-forming port, 1021-arc-shaped protrusion, 1022-adhesion surface. Detailed Implementation

[0054] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore their detailed description will be omitted. Furthermore, the drawings are merely illustrative of the present invention and are not necessarily drawn to scale.

[0055] Although relative terms such as "up" and "down" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples shown in the accompanying drawings. It is understood that if the device of the icon is flipped upside down, the component described as "up" will become the component described as "down." When a structure is "up" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0056] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0057] like Figure 1 and Figure 2As shown in the figure, the flexible circuit board 1 includes components 12 and a flexible circuit board body 11, the components 12 are connected to the welding surface 111 of the flexible circuit board body 11, in order to avoid the corrosion medium eroding the solder pad 122 of the components 12, and the welding position of the components 12 and the flexible circuit board 1, causing the conduction of the flexible circuit board 1 to be poor. The whole components 12 are completely wrapped by the wrapping part 14, the side of the wrapping part 14 away from the flexible circuit board body 11 is higher than the side of the components 12 away from the flexible circuit board body 11, and the insulating protective layer 15 is covered on the welding surface 111 of the flexible circuit board body 11 and the side of the wrapping part 14 away from the flexible circuit board 1, but the thickness of the flexible circuit board 1 is increased by 0.2-0.5mm.

[0058] When the flexible circuit board 1 is applied to a display device, the side of the flexible circuit board 1 away from the insulating protective layer 15 is provided with a protective layer 2, the side of the protective layer 2 away from the flexible circuit board 1 is provided with a display layer 3, and the side of the display layer 3 away from the flexible circuit board 1 is provided with a cover plate 6. In the trend of the overall thinning of the display device, the internal space of the display device is more limited, the components 12 on the flexible circuit board 1 belong to the position with the largest thickness in the display module, and the thinning of this area directly affects the corrosion resistance of the flexible circuit board 1. In order to reduce the thickness of the flexible circuit board 1, the packaging of the components 12 can be replaced from a larger size to a smaller size, but the reduction of the packaging size will cause the corrosion resistance of the components 12 to be weakened.

[0059] As shown in the figure, Figure 3 and Figure 4 As shown in the figure, the components 12 include a component body 121 and a solder pad 122, the solder pad 122 is arranged on the periphery of the component body 121, and the wrapping part 14 only covers the side of the solder pad 122 away from the component body 121 in the direction parallel to the welding surface 111, the solder pad 122 and the connecting layer 13 between the welding surface 111 of the flexible circuit board body 11. As shown in the figure, Figure 5 The side of the corrosion point away from the flexible circuit board body 11 is flush with the side of the components 12 away from the flexible circuit board body 11, the wrapping part 14 is changed from full wrapping to half wrapping, the corrosion medium will invade between the insulating protective layer 15 and the wrapping part 14 from between the insulating protective layer 15 and the flexible circuit board body 11, the side of the components 12 away from the flexible circuit board body 11 is exposed, the corrosion medium will pass between the insulating protective layer 15 and the wrapping part 14, and gradually corrode the solder pad 122 in the exposed metal area on the upper surface of the components 12, in addition, the corrosion medium will also penetrate into the connecting layer 13 through the junction between the wrapping part 14 and the solder pad 122, causing the conduction of the flexible circuit board 1 to be poor.

[0060] Based on this, the utility model embodiment provides a kind of flexible circuit board 1. As shown in the figure, Figures 6 to 19As shown, the flexible circuit board 1 includes a flexible circuit board body 11, components 12, a connecting layer 13, a wrapping portion 14, and an insulating protective layer 15. The flexible circuit board body 11 has a soldering surface 111. Components 12 are disposed on the soldering surface 111 of the flexible circuit board 1. Components 12 include a component body 121 and a pad 122. The pad 122 is disposed around the component body 121. The connecting layer 13 connects the soldering surface 111 of the flexible circuit board 1 and the pad 122. The wrapping portion 14 is disposed on the side of the connecting layer 13 and the pad 122 away from the component body 121. The insulating protective layer 15 covers the soldering surface 111 of the flexible circuit board body 11, the side of the wrapping portion 14 away from the flexible circuit board body 11, and the side of the component 12 away from the flexible circuit board body 11. A first receiving cavity 16 is formed between the wrapping portion 14, the insulating protective layer 15, and the flexible circuit board body 11.

[0061] The flexible circuit board 1 includes a flexible circuit board body 11, a wrapping portion 14, and an insulating protective layer 15. A first receiving cavity 16 is formed between the wrapping portion 14, the insulating protective layer 15, and the flexible circuit board body 11. When a corrosive medium seeps into the edge of the flexible circuit board 1, the corrosive medium flows along the space between the insulating protective layer 15 and the flexible circuit board body 11 into the first receiving cavity 16. The side of the wrapping portion 14 away from the component 12 can block the corrosive medium, preventing it from corroding the pads 122 of the component 12 and the connection layer 13 between the pads 122 and the soldering surface 111 of the flexible circuit board body 11, thus preventing poor conductivity of the flexible circuit board 1.

[0062] The flexible circuit board 1 involved in the embodiments of this utility model will be described in detail below with reference to specific examples.

[0063] like Figure 6 and Figure 7 As shown, the flexible circuit board 1 may include a flexible circuit board body 11 and components 12. The flexible circuit board body 11 has a soldering surface 111, and the soldering surface 111 has a component area 1111. Components 12 are disposed in the component area 1111. A peripheral area 1112 is provided around the component area 1111, and the peripheral area 1112 has a fingerprint opening 1113. The fingerprint opening 1113 is located between two adjacent components 12. Component 12 includes a component body 121 and a pad 122. The pad 122 is disposed around the component body 121. A connecting layer 13 is provided between the pad 122 and the component area 1111 of the soldering surface 111. The connecting layer 13 connects the soldering surface 111 of the flexible circuit board 1 and the pad 122. The side of the pad 122 away from the flexible circuit board body 11 may be flush with the side of the component body 121 away from the flexible circuit board body 11.

[0064] The flexible circuit board 1 may further include a wrapping portion 14, which is disposed on the side of the connection layer 13 and the pad 122 away from the component body 121 in a direction parallel to the soldering surface 111. The wrapping portion 14 extends from the side of the connection layer 13 to the side of the pad 122 in a direction perpendicular to the soldering surface 111, with the side of the wrapping portion 14 away from the flexible circuit board body 11 being lower than the sides of the pad 122 and the component body 121 away from the flexible circuit board body 11. It is understood that there is a step difference between the side of the wrapping portion 14 away from the flexible circuit board body 11 and the side of the pad 122 away from the flexible circuit board body 11.

[0065] The flexible circuit board 1 may further include an insulating protective layer 15, which covers the component body 121 and the side of the pad 122 away from the flexible circuit board body 11. The insulating protective layer 15 extends from the side of the pad 122 away from the flexible circuit board body 11 and overlaps with the side of the wrapping portion 14 away from the flexible circuit board body 11. The insulating protective layer 15 extends from the side of the wrapping portion 14 away from the flexible circuit board body 11 and overlaps with the periphery of the component area 1111 of the soldering surface 111 of the flexible circuit board body 11. Figure 8 and Figure 9 As shown, the component 12 is surrounded by a wrapping portion 14. The insulating protective layer 15 forms an attachment protrusion 153 in the area where the component 12 and the wrapping portion 14 are attached. The insulating protective layer 15 has a through hole 154 between two attachment protrusions 153. The shape and size of the through hole 154 are the same as the shape and size of the fingerprint opening 1113, and the outline of the through hole 154 overlaps with the outline of the fingerprint opening 1113.

[0066] like Figure 10 As shown, since the side of the wrapping portion 14 away from the flexible circuit board body 11 is significantly higher than the soldering surface 111 of the flexible circuit board body 11, the insulating protective layer 15 forms a first transition section 151 between the edge of the wrapping portion 14 away from the flexible circuit board body 11 and the soldering surface 111 of the flexible circuit board 11. A first receiving cavity 16 is formed between the side of the wrapping portion 14 away from the component 12, the first transition section 151 of the insulating protective layer 15, and the soldering surface 111 of the flexible circuit board body 11, parallel to the soldering surface. When corrosive media penetrates the edge of the flexible circuit board body 11 or the periphery of the fingerprint opening 1113, the corrosive media... Figure 10 As shown in the path, after the corrosive medium invades the first receiving cavity 16 between the insulating protective layer 15 and the flexible circuit board 1, the corrosive medium is blocked by the wrapping part 14 along the side away from the component 12 in the direction parallel to the welding surface, so as to prevent the corrosive medium from corroding the pad 122 of the component 12 and the connection layer 13 between the pad 122 and the welding surface 111 of the flexible circuit board body 11, and to prevent poor conductivity of the flexible circuit board 1.

[0067] like Figures 11 to 15 As shown, the side of the wrapping portion 14 away from the component 12 along the direction parallel to the soldering surface includes a first blocking surface 141. One end of the first blocking surface 141 is attached to the soldering surface 111 of the flexible circuit board body 11, and the other end is close to the insulating protective layer 15. The first blocking surface 141 is an arc-shaped surface that is concave towards the component body 121. The distance between the first blocking surface 141 and the side of the pad 122 away from the component body 121 is the first dimension L1 of the wrapping portion 14. The first dimension L1 of the wrapping portion 14 gradually increases along the direction away from the flexible circuit board body 11. The side of the wrapping portion 14 away from the component 12 along the direction perpendicular to the soldering surface also includes a second blocking surface 142. The second blocking surface 142 connects the first blocking surface 141 and the side of the wrapping portion 14 away from the flexible circuit board body 11. The second blocking surface 142 is approximately parallel to the side of the pad 122 away from the component body 121, and the included angle between the second blocking surface 142 and the side of the pad 122 away from the component body 121 is -5° to -5°.

[0068] The side of the wrapping portion 14 away from the flexible circuit board body 11 is the support surface 143. The distance between the support surface 143 and the welding surface 111 of the flexible circuit board body 11 is the second dimension L2. To prevent moisture from entering and to avoid the wrapping portion 14 from taking up too much space, the second dimension L2 of the wrapping portion 14 is smaller than the height H1 of the component 12 (the height H1 of the component 12 is usually between 0.5 and 0.9 mm). The maximum first dimension L1 of the wrapping portion 14 is < 0.6 mm, that is, the width of the support surface 143 is < 0.6 mm. The maximum first dimension L1 and the second dimension L2 of the wrapping portion 14 can be adjusted within the above range according to the dispensing process capability.

[0069] The cross-sectional area of ​​the first receiving cavity 16 is: S > C2 × ΔL × H / C1; where C1 is the perimeter of the device area 1111 of the welding surface 111, C2 is the length of the edge of the insulating protective layer 15, ΔL is the absorption volume per unit length of the insulating protective layer 15, and H is the water absorption time. The size of the first receiving cavity 16 is always sufficient to accommodate the intruding corrosive medium, ensuring the corrosion resistance of the encapsulated part 14. It should be noted that the corrosive medium mentioned above can be water or a water vapor mixture.

[0070] To enhance the blocking effect of the first blocking surface 141 on corrosive media, the increase in the first dimension L1 of the wrapping portion 14 can be set to gradually increase in the direction away from the flexible circuit board body 11. The first blocking surface 141 can be set as an arc-shaped surface, its area extended, and its inclination gradually increased in the direction away from the flexible circuit board body 11. When the maximum first dimension L1 of the wrapping portion 14 is less than or equal to the second dimension L2, the shape of the first blocking surface 141 is as follows: Figure 11The arc surface shown can have a length of 1 / 4 of a circle. When there is sufficient horizontal space and the largest first dimension L1 of the wrapping part 14 is greater than the second dimension L2, the shape of the first blocking surface 141 can be as follows: Figure 12 The elliptical arc surface shown can increase the space for containing corrosive media.

[0071] In one possible implementation, the angle between the tangent T1 of the first blocking surface 141 on the side away from the flexible circuit board body 11 and the welding surface 111 of the flexible circuit board 1 is greater than 0 degrees and less than 90 degrees, which can effectively prevent moisture from intruding along the first blocking surface 141 to the second blocking surface 142 and the support surface 143. In this embodiment, the tangent of the end of the first blocking surface 141 away from the flexible circuit board body 11 can be set to be parallel to the welding surface 111 of the flexible circuit board 1.

[0072] like Figure 13 As shown, when the shape of the first blocking surface 141 is affected by the manufacturing capability, the first blocking surface 141 can be selected as an inclined surface with lower processing difficulty. The increase in the first dimension L1 of the wrapping part 14 is the same in the direction away from the flexible circuit board body 11. The included angle between the first blocking surface 141 and the side of the pad 122 away from the component body 121 is less than 90 degrees.

[0073] like Figures 11 to 13 As shown, when the support surface 143 is parallel to the soldering surface 111 of the flexible circuit board body 11, when the insulating protective layer 15 transitions from the side of the pad 122 away from the flexible circuit board body 11 to the support surface 143 of the wrapping portion 14, since there is a step difference between the side of the insulating protective layer 15 away from the pad 122 and the support surface 143 of the wrapping portion 14, the insulating protective layer 15 will form a second transition section 152 between the edge of the side of the pad 122 away from the flexible circuit board body 11 and the side of the wrapping portion 14 away from the flexible circuit board body 11. The second transition section 152, the support surface 143 of the wrapping portion 14 and the side of the pad 122 can easily form a second receiving cavity 17, which makes it easy for corrosive media to remain in the second receiving cavity 17 when it invades between the support surface 143 of the wrapping portion 14 and the insulating protective layer 15, increasing the risk of the pad 122 being corroded.

[0074] Therefore, the second dimension L2 of the wrapping portion 14 gradually increases along the direction close to the component body 121, that is, the support surface 143 of the wrapping portion 14 is an inclined surface, so that when the insulating protective layer 15 transitions from the side of the pad 122 away from the flexible circuit board body 11 to the support surface 143 of the wrapping portion 14, it can fit tightly with the support surface 143 of the wrapping portion 14, avoiding the retention of corrosive media, thereby reducing the risk of corrosion of the pad 122. Figure 14 As shown, the support surface 143 of the wrapping part 14 can be set as an inclined plane, such as... Figure 15As shown, the support surface 143 can also be an arc-shaped surface that protrudes away from the flexible circuit board body 11. The width of the arc-shaped surface is greater than the width of the inclined plane, which can increase the climbing distance of the corrosive medium and further enhance the corrosion resistance of the flexible circuit board 1.

[0075] by Figure 11 Taking the structure of the middle wrapping part 14 as an example, the formation process of the first receiving cavity 16 will be explained:

[0076] like Figures 16 to 19 As shown, when the pad 122 is soldered to the device area 1111 of the soldering surface 111 of the flexible circuit board body 11 through the connecting layer 13, a mold 10 as shown is provided on the soldering surface 111 of the flexible circuit board 1. The mold 10 has a forming opening 102, the size of which is adapted to the size of the component 12, and the side of the forming opening 102 is close to the side of the pad 122 of the component 12. To facilitate demolding, the mold 10 is divided into two sub-modules 101, which together form the forming opening. The side of the forming opening 102 has an arc-shaped protrusion 1021 and a mating surface 1022. The mating surface 1022 is recessed towards the center of the mold 10 relative to the arc-shaped protrusion 1021. The arc-shaped protrusion 1021 matches the first blocking surface 141, and the mating surface 1022 matches the second blocking surface 142.

[0077] When the two sub-modules 101 are closed, i.e., when the mating surfaces 1022 of the two sub-modules 101 come into contact with each other, the side of the molding opening 102, the side of the component 12 pad 122, and the soldering surface 111 of the flexible circuit board 1 form a filling space. The wrapping part 14 can be made of anti-corrosion adhesive. The anti-corrosion adhesive is poured into the filling space, and the amount of adhesive is controlled to ensure that the anti-corrosion adhesive does not overflow the mold 10. The height of the anti-corrosion adhesive is less than or equal to the height of the pad 122 and the height of the component body 121. After the adhesive is applied, the anti-corrosion adhesive is cured and shaped. Then the two sub-modules 101 are separated, the mold 10 is removed, and the wrapping part 14 is formed on the side away from the component 12.

[0078] Finally, the insulating protective layer 15 is attached to the welding surface 111 of the flexible circuit board body 11, the side of the wrapping portion 14 away from the flexible circuit board body 11, and the side of the component 12 away from the flexible circuit board body 11, thus obtaining the first receiving cavity 16 that blocks corrosive media.

[0079] This utility model also provides a display module. For example... Figures 20 to 22As shown, the display module may include a flexible circuit board 1, a middle frame 8 and a flexible spacer 9. The welding surface 111 of the flexible circuit board body 11 includes a device area 1111. Components 12 are disposed in the device area 1111. The flexible spacer 9 is interference-fitted between the middle frame 8 and the flexible circuit board body 11 and surrounds the periphery of the device area 1111.

[0080] Each component 12 is surrounded by a flexible spacer 9. The flexible spacer 9 can seal the components 12 within the component area 1111, ensuring the corrosion resistance of the flexible circuit board 1 and thus ensuring the reliability of the display module. In this embodiment, a conventional flexible circuit board 1 is used, which avoids the problem of unevenness of the flexible circuit board 1 caused by the volume change of the wrapping part 14 during curing after the wrapping part 14 is set around the component area 1111, which would otherwise cause the insulating protective layer 15 to lift up.

[0081] A heat dissipation layer 7 is provided on the side of the flexible circuit board body 11 away from the insulating protective layer 15. A protective layer 2 is provided on the side of the heat dissipation layer 7 away from the flexible circuit board 1. A display layer 3 is provided on the side of the protective layer 2 away from the flexible circuit board 1. A polarizer 4 can also be provided on the side of the display layer 3 away from the flexible circuit board 1 to reduce the reflection of the display layer 3. A cover plate 6 can also be provided on the side of the polarizer 4 away from the flexible circuit board 1. An optical adhesive layer 5 is provided between the cover plate 6 and the polarizer 4 to bond the cover plate 6 to the polarizer 4.

[0082] It should be further explained that the middle frame 8 includes a bottom 81 and a side 82. The side 82 is connected to the edge of the bottom 81 and is perpendicular to the bottom 81. The side 82 is provided with a mounting groove 821. The cover plate 6 overlaps in the mounting groove 821 and contacts the side wall and bottom wall of the mounting groove 821. The flexible spacer 9 is interference-fitted with the welding surface 111 of the flexible circuit board body 11 and the bottom 81 of the middle frame 8.

[0083] like Figure 22 As shown, the thickness of the flexible spacer 9 must satisfy: (H-δ)×E×S<F; H is the thickness of the flexible spacer 9 before assembly, δ is the gap between the flexible circuit board 1 and the middle frame 8, E is the elastic modulus of the flexible spacer 9, the contact area between the flexible spacer 9 and the flexible circuit board 1 is S, and the maximum force that the display layer 3 can withstand is F. The thickness H of the flexible spacer 9 before assembly is greater than the gap δ between the flexible circuit board 1 and the middle frame 8. By limiting it with the above formula, it is ensured that the flexible spacer 9, while having an interference fit with the middle frame 8 and the flexible circuit board body 11, avoids damaging the display layer 3 and affecting the display effect.

[0084] This utility model also provides a display module. For example... Figure 23As shown, the display module may include the flexible circuit board 1 mentioned in any of the embodiments of this utility model above. The specific structure and beneficial effects of the flexible circuit board 1 have been described in detail above, and therefore will not be repeated here. It is understood that improving the corrosion resistance of the flexible circuit board 1 can improve the reliability of the display module.

[0085] The display module may also include a mid-frame 8 and a flexible spacer 9. The welding surface 111 of the flexible circuit board body 11 includes a device area 1111. Components 12 are disposed in the device area 1111. The flexible spacer 9 is interference-fitted between the mid-frame 8 and the flexible circuit board body 11. The flexible spacer 9 surrounds the periphery of the device area 1111. Here, the flexible spacer 9 is disposed on the periphery of the insulating protective layer 15.

[0086] The flexible spacer 9 seals the edge of the insulating protective layer 15, preventing corrosive media from entering the device area 1111 between the insulating protective layer 15 and the flexible circuit board body 11, thus corroding the components 12 and achieving corrosion protection for the flexible circuit board 1. Even if corrosive media enters the area enclosed by the flexible spacer 9, the side of the wrapping portion 14 away from the components 12 can also block the corrosive media, preventing it from corroding the pads 122 of the components 12 and the connection layer 13 between the pads and the solder surface 111 of the flexible circuit board body 11, thus preventing poor conductivity of the flexible circuit board 1. In summary, this display module has good corrosion resistance.

[0087] This invention also provides a display device. This display device may include the display module described in any of the above embodiments of this invention. The specific structure and beneficial effects of the display module have been described in detail above, and therefore will not be repeated here.

[0088] It should be noted that, in addition to the display module, the display device also includes other necessary components and parts, such as the housing, control circuit board, power cord, etc. Those skilled in the art can make corresponding additions according to the specific usage requirements of the display device, which will not be elaborated here.

[0089] When the display module has the structure shown in the figure, the display device can be a traditional electronic device, such as a mobile phone, computer, television and video recorder, or an emerging wearable device, such as virtual reality device and augmented reality device, which will not be listed here.

[0090] Other embodiments of the present invention will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of the present invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of the present invention are indicated by the appended claims.

Claims

1. A flexible circuit board, characterized in that, include: The flexible circuit board body has a soldering surface; A component is disposed on a soldering surface. The component includes a component body and a solder pad, and the solder pad is disposed on the periphery of the component body. A connecting layer that connects the welding surface to the solder pad; The wrapping portion is located on the side of the connecting layer and the solder pad away from the component body; An insulating protective layer covers the welding surface, the side of the wrapping portion away from the flexible circuit board body, and the side of the component away from the flexible circuit board body; A first receiving cavity is formed between the wrapping part, the insulating protective layer and the flexible circuit board body.

2. The flexible circuit board according to claim 1, characterized in that, The side of the wrapping portion away from the component includes a first blocking surface. One end of the first blocking surface is in contact with the soldering surface, and the other end is close to the insulating protective layer. The distance between the first blocking surface and the side of the solder pad away from the component body is the first dimension of the wrapping portion. The first dimension of the wrapping portion gradually increases in the direction away from the flexible circuit board body.

3. The flexible circuit board according to claim 2, characterized in that, The first blocking surface is an arc-shaped surface that is concave towards the body of the component.

4. The flexible circuit board according to claim 3, characterized in that, The side of the wrapping portion away from the flexible circuit board body is the support surface. The distance between the support surface and the welding surface is the second dimension. When the maximum first dimension of the wrapping portion is greater than the second dimension, the shape of the first blocking surface is an elliptical arc surface.

5. The flexible circuit board according to claim 3, characterized in that, The side of the wrapping portion away from the flexible circuit board body is the support surface, and the distance between the support surface and the welding surface is the second dimension. When the maximum first dimension of the wrapping portion is less than or equal to the second dimension, the shape of the first blocking surface is an arc surface.

6. The flexible circuit board according to claim 3, characterized in that, The angle between the tangent of the first blocking surface on the side away from the flexible circuit board body and the welding surface of the flexible circuit board is greater than 0 degrees and less than 90 degrees.

7. The flexible circuit board according to claim 2, characterized in that, The first blocking surface is an inclined surface, the increase in the first dimension of the wrapping portion is the same in the direction away from the flexible circuit board body, and the angle between the first blocking surface and the side of the pad away from the component body is less than 90 degrees.

8. The flexible circuit board according to claim 1, characterized in that, The cross-sectional area of ​​the first receiving cavity is: S>C2×△L×H / C1; Wherein, C1 is the perimeter of the device area of ​​the welding surface, C2 is the length of the edge of the insulating protective layer, ΔL is the absorption volume per unit length of the insulating protective layer, and H is the water absorption time.

9. The flexible circuit board according to claim 2, characterized in that, The side of the packaged portion away from the component also includes a second blocking surface, which is connected to the other end of the first blocking surface. The angle between the second blocking surface and the side of the pad away from the component body is -5 to 5°.

10. The flexible circuit board according to claim 4 or 5, characterized in that, The second dimension of the package gradually increases along the direction closer to the component body.

11. The flexible circuit board according to claim 10, characterized in that, The supporting surface is an arc-shaped surface that protrudes away from the flexible circuit board body.

12. The flexible circuit board according to claim 1, characterized in that, The side of the wrapping portion away from the flexible circuit board body is lower than the side of the solder pad away from the flexible circuit board body.

13. A display module, characterized in that, Includes the flexible circuit board as described in any one of claims 1 to 12.

14. The display module according to claim 13, characterized in that, The display module further includes a mid-frame and a flexible spacer. The welding surface includes a device area, and the components are disposed in the device area. The flexible spacer is interference-fitted between the mid-frame and the flexible circuit board body, and the flexible spacer is located on the periphery of the device area.

15. The display module according to claim 14, characterized in that, The display module also includes: A protective layer is disposed on the side of the flexible circuit board body away from the insulating protective layer; The display layer is located on the side of the protective layer away from the flexible circuit board body.

16. The display module according to claim 15, characterized in that, The thickness of the flexible spacer portion must meet the following requirements; (H-δ)×E×S<F; H is the thickness of the flexible spacer before assembly, δ is the gap between the flexible circuit board and the middle frame, E is the elastic modulus of the flexible spacer, S is the contact area between the flexible spacer and the flexible circuit board, and F is the maximum force that the display layer can withstand.

17. A display device, characterized in that, Includes the display module as described in claim 16.

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