Circuit board, display module and display device

Abstract

The invention relates to a circuit board, the circuit board comprises a circuit board body, a protection layer and a blocking dam, the circuit board body comprises a wiring area and a pin area which are sequentially arranged at intervals along a first direction, the protection layer covers the wiring area, the blocking dam covers one end, close to the pin area, of the wiring area, and the protection layer flows towards the pin area along the wiring area before being cured. The height difference formed by the blocking dam and the circuit board body can block the flowing protective layer and prevent the protective layer from flowing to the binding area of the pin area, so that the binding effect of the pins is ensured, and the final reliability of the display module is ensured. The invention further provides a display module comprising the circuit board and a display device comprising the display module.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a circuit board, a display module and a display device. Background Art

[0002] In application scenarios such as aviation, automotive, and industrial control that have high requirements for the reliability of display modules, it is necessary to coat a protective layer on the surface of the circuit board to improve the circuit board's insulation, moisture-proof, anti-leakage, shock-proof, dust-proof, and anti-corrosion functions.

[0003] However, the protective layer is in liquid form before solidification. During the process of coating the protective layer on the circuit board surface, it is easy to seep from the routing area to the pin area, resulting in poor binding in the pin area, thus affecting the ultimate reliability of the display module.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present disclosure, and therefore may include information that does not constitute the prior art known to ordinary technicians in the field. Summary of the invention

[0005] The purpose of the present disclosure is to overcome the above-mentioned deficiencies of the prior art and to provide a circuit board, a display module and a display device.

[0006] According to one aspect of the present disclosure, a circuit board is provided, comprising a circuit board body, a protective layer and a blocking dam, wherein the circuit board body comprises a routing area and a pin area which are arranged in sequence and spaced apart along a first direction; the protective layer is arranged on one side of the circuit board body, the protective layer covers the routing area, and the protective layer flows along the routing area toward the pin area before solidification; the blocking dam and the protective layer are arranged on the same side of the circuit board body, the blocking dam covers one end of the routing area close to the pin area, and the blocking dam can form a barrier to the flowing protective layer.

[0007] In one embodiment of the present disclosure, the barrier dam includes a first barrier layer and a second barrier layer sequentially arranged in a direction away from the circuit board body, and an edge of the second barrier layer adjacent to the protective layer is closer to the pin area than an edge of the first barrier layer adjacent to the protective layer.

[0008] In one embodiment of the present disclosure, a guide groove is provided on one side of the blocking dam close to the routing area. The guide groove is provided along a second direction and extends to an edge of the blocking dam. The second direction is perpendicular to the first direction.

[0009] In one embodiment of the present disclosure, the barrier dam is gradually inclined in a direction away from the circuit board body and away from the pin area.

[0010] In one embodiment of the present disclosure, the circuit board body includes a substrate and a first conductive layer, the first conductive layer includes a plurality of pins, the plurality of pins are located in a pin area and are arranged parallel to each other along a first direction, the first conductive layer also includes a circuit trace, the circuit trace is located in the trace area, a transition area is provided between the trace area and the pin area, a plurality of adapter wires are provided in parallel to each other along the first direction in the transition area, and each adapter wire is respectively connected to the circuit trace and the plurality of pins.

[0011] In one embodiment of the present disclosure, the adapter wires are arranged in the same layer as the circuit wiring and the pins, a groove is formed between two adjacent adapter wires, and the barrier dam fills at least one end of each groove close to the wiring area.

[0012] In one embodiment of the present disclosure, the circuit board also includes an insulating layer, which is arranged between the substrate and the first conductive layer, the adapter wire is arranged between the insulating layer and the substrate, the pin is connected to the adapter wire through a first via hole, and the circuit line is connected to the adapter wire through a second via hole.

[0013] In one embodiment of the present disclosure, the orthographic projection of the adapter wire on the substrate overlaps with the orthographic projection of the circuit trace on the substrate to form an overlapping region, and the orthographic projection of the second via on the substrate is located in the overlapping region.

[0014] In one embodiment of the present disclosure, an orthographic projection of the second via hole on the substrate is located on a side of the overlapping region away from the pin region.

[0015] In one embodiment of the present disclosure, different circuit traces are connected to different pins through different second vias, and orthographic projections of at least some of the second vias in the first direction do not overlap.

[0016] In one embodiment of the present disclosure, at least one buffer segment is formed between two adjacent transfer wires, and a width of the buffer segment is greater than a distance between two adjacent pins.

[0017] In one embodiment of the present disclosure, the width of the buffer segment gradually increases in a direction approaching the pin region.

[0018] In one embodiment of the present disclosure, the width of the buffer segment gradually increases and then gradually decreases in a direction approaching the pin region.

[0019] In one embodiment of the present disclosure, the contour of the edge of the buffer segment is an arc shape.

[0020] In one embodiment of the present disclosure, a plurality of buffer segments are formed between two adjacent transfer lines, and the widths of the plurality of buffer segments gradually increase in a direction approaching the pin region.

[0021] In one embodiment of the present disclosure, a patterned protective layer is provided on the side of the circuit routing away from the substrate, the protective layer is located in the routing area, the blocking dam covers the side of the protective layer close to the pin area, the routing area includes a device area away from the pin area, and the blocking dam does not contact the device area.

[0022] In one embodiment of the present disclosure, the protection layer covers one end of the circuit trace close to the pin region and is at least partially located in the transition region.

[0023] In one embodiment of the present disclosure, the barrier dam at least partially covers a region of the insulating layer located in the transition region.

[0024] In one embodiment of the present disclosure, the barrier dam covers the patch cord.

[0025] In one embodiment of the present disclosure, the barrier dam overlaps with an end of the pin close to the adapter wire, and the overlapping width of the barrier dam and the pin is less than one fifth of the length of the pin.

[0026] In one embodiment of the present disclosure, the protective layer is a conformal coating.

[0027] According to another aspect of the present disclosure, a display module is provided, including a display panel and a circuit board that are electrically connected, wherein the circuit board is the circuit board provided in one aspect of the present disclosure.

[0028] According to another aspect of the present disclosure, a display device is provided, including the display module provided by one aspect of the present disclosure.

[0029] The circuit board disclosed in the present invention includes a circuit board body, a protective layer and a blocking dam. The circuit board body includes a routing area and a pin area which are arranged in sequence along a first direction. The protective layer covers the routing area. The blocking dam covers one end of the routing area close to the pin area. The protective layer flows along the routing area to the pin area before solidification. The height difference formed by the blocking dam and the circuit board body can block the flowing protective layer, preventing the protective layer from flowing to the binding area of ​​the pin area, thereby ensuring the binding effect of the pins and ensuring the ultimate reliability of the display module.

[0030] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0032] Figure 1 A schematic cross-sectional view of the pin area of ​​the circuit board along the second direction according to an embodiment of the present disclosure when the liquid protective layer seeps into the pin area.

[0033] Figure 2 A schematic cross-sectional view of the pin area of ​​the circuit board along the second direction according to an embodiment of the present disclosure when the liquid protective layer seeps into the pin area.

[0034] Figure 3 It is a schematic cross-sectional view of the circuit board along the first direction involved in the embodiment of the present disclosure when no blocking dam is provided.

[0035] Figure 4 A schematic cross-sectional view of a circuit board along a first direction according to an embodiment of the present disclosure when a barrier dam is provided.

[0036] Figure 5 A schematic plan view of a circuit board according to an embodiment of the present disclosure when a barrier dam is provided.

[0037] Figure 6 A schematic cross-sectional view of a circuit board according to an embodiment of the present disclosure is shown when the barrier dam includes a first barrier layer and a second barrier layer, and the second barrier layer and the silk-screen layer are made of the same layer and material.

[0038] Figure 7 A schematic plan view of a circuit board according to an embodiment of the present disclosure when the barrier dam includes a first barrier layer and a second barrier layer, and the second barrier layer and the silk-screen layer are made of the same layer and material.

[0039] Figure 8 A schematic cross-sectional view of a circuit board according to an embodiment of the present disclosure is provided when the barrier dam includes a first barrier layer and a second barrier layer, and the second barrier layer and the second filling layer are made of the same layer and material.

[0040] Fig. 9 A schematic plan view of a circuit board according to an embodiment of the present disclosure is shown when the barrier dam includes a first barrier layer and a second barrier layer, and the second barrier layer and the second filling layer are made of the same layer and material.

[0041] Fig.10 A schematic cross-sectional view of the circuit board involved in the embodiment of the present disclosure when the adapter wires, pins and circuit wiring are on different layers.

[0042] Fig.11 It is a schematic cross-sectional view of the circuit board involved in the embodiment of the present disclosure when the orthographic projection of the second via hole on the substrate is located in the overlapping area of ​​the orthographic projection of the adapter wire on the substrate and the device area.

[0043] Fig.12 It is a cross-sectional schematic diagram of the circuit board involved in the embodiment of the present disclosure when the orthographic projections of the second via holes in the first direction do not overlap.

[0044] Fig.13 A schematic cross-sectional view of the circuit board involved in an embodiment of the present disclosure when the protective layer covers one end of the circuit trace close to the pin area and covers a portion of the transition area.

[0045] Fig.14 A schematic cross-sectional view of the circuit board involved in an embodiment of the present disclosure is a diagram showing a situation in which the barrier dam is arranged along a direction away from the circuit board body and gradually tilted toward a direction away from the pin area.

[0046] Fig.15 A schematic cross-sectional view of the circuit board involved in an embodiment of the present disclosure is a diagram showing a situation in which the barrier dam is arranged to be gradually inclined from a direction away from the circuit board body to a direction close to the pin area.

[0047] Fig.16 A schematic cross-sectional view of the circuit board involved in an embodiment of the present disclosure when a guide groove is provided on a side of the blocking dam close to the wiring area.

[0048] Fig.17 When the barrier dam includes a first barrier layer and a second barrier layer, and the barrier dam is arranged to be gradually inclined from a direction away from the circuit board body to a direction away from the pin area, an embodiment of the present disclosure relates to a schematic diagram of the arrangement of the guide groove on the barrier dam.

[0049] Fig.18 A plan view of the first conductive layer involved in an embodiment of the present disclosure when the distance between adjacent transfer wires is equal to the distance between adjacent pins.

[0050] Fig.19 A schematic plan view of the first conductive layer involved in an embodiment of the present disclosure when the width of the buffer segment is greater than the distance between adjacent pins.

[0051] Fig. 20 It is a plan view of the first conductive layer involved in the embodiment of the present disclosure when the width of the buffer segment gradually increases in a direction approaching the pin area.

[0052] Fig.21 The schematic plan view of the first conductive layer involved in the embodiment of the present disclosure is when the width of the buffer segment is set to gradually increase first and then gradually decrease along the direction close to the pin area.

[0053] Fig. 22 A schematic plan view of the first conductive layer involved in an embodiment of the present disclosure is when the width of the buffer segment is set to gradually increase and then gradually decrease along a direction close to the pin area, and the contour of the edge of the buffer segment is an arc shape.

[0054] Fig.23 A schematic plan view of the first conductive layer involved in an embodiment of the present disclosure is a diagram showing a plurality of buffer segments formed between two adjacent transfer lines, wherein the widths of the plurality of buffer segments gradually increase in a direction approaching the pin area.

[0055] Fig.24 A partial plan view of the first conductive layer involved in an embodiment of the present disclosure is a schematic diagram showing a situation in which the width of the buffer segment is first gradually increased and then gradually decreased along a direction close to the pin region.

[0056] Description of reference numerals:

[0057] 1. Circuit board body, 11. Base, 12. First conductive layer, 121. Circuit routing, 122. Adapter, 123. Pin, 124. Groove, 1241. Buffer section, 13. Protective layer, 14. Insulating layer, 101. Routing area, 1011. Overlapping area, 102. Transition area, 101. Pin area, 141. First via, 142. Second via, 2. Protective layer, 3. Barrier dam, 31. First barrier layer, 32. Second barrier layer, 301. Guide groove. DETAILED DESCRIPTION

[0058] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present disclosure will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their detailed description will be omitted. In addition, the drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale.

[0059] Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of the illustration to another component, these terms are used in this specification only for convenience, such as according to the orientation of the examples described in the drawings. It is understood that if the device of the illustration is turned upside down, the component described as "upper" will become the component "lower". When a structure is "on" other structures, it may mean that the structure is formed integrally on the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

[0060] The terms "a", "an", "the", "said" 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 express an open-ended inclusive meaning and mean that additional elements / components / etc. may exist in addition to the listed elements / components / etc.; the terms "first", "second" and "third" etc. are used merely as labels and are not intended to limit the quantity of their objects.

[0061] like Figures 1 to 3As shown, the pin area 103 of the circuit board is provided with a plurality of pins 123 parallel to each other, and adjacent pins 123 are usually spaced apart. In application scenarios such as aviation, vehicle-mounted, and industrial control, which have high requirements on the reliability of the display module, a protective layer 2 is coated on the wiring area 101 of the circuit board to improve the insulation, moisture-proof, leakage-proof, shock-proof, dust-proof, and corrosion-proof functions of the circuit board. It should be noted that the protective layer 2 can be a three-proof paint. However, the three-proof paint is usually a transparent UV curing glue, which is liquid before curing, has low viscosity, and has fluidity close to water, and is easy to penetrate and sputter. In the process of spray coating on the surface of the circuit board, the low viscosity of the three-proof paint makes it easy to seep uncontrolled. In severe cases, it will seep into the pin area 101 and fill between two adjacent pins 123, resulting in poor binding of the pins 123, affecting the final reliability of the display module.

[0062] Based on this, the present disclosure provides a circuit board. Figures 4 to 24 As shown, the circuit board includes a circuit board body 1, a protective layer 2 and a blocking dam 3. The circuit board body 1 includes a routing area 101 and a pin area 101 which are arranged in sequence along a first direction; the protective layer 2 is arranged on one side of the circuit board body 1, the protective layer 2 covers the routing area 101, and the protective layer 2 flows along the routing area 101 to the pin area 101 before solidification; the blocking dam 3 and the protective layer 2 are arranged on the same side of the circuit board body 1, the blocking dam 3 covers one end of the routing area 101 close to the pin area 101, and the blocking dam 3 can form a barrier to the flowing protective layer 2.

[0063] The protective layer 2 covers the routing area 101, and the blocking dam 3 covers one end of the routing area 101 close to the pin area 101. The protective layer 2 flows along the routing area 101 to the pin area 101 before solidification. The height difference formed by the blocking dam 3 and the circuit board body 1 can block the flowing protective layer 2, preventing the protective layer 2 from flowing to the binding area of ​​the pin area 101, thereby ensuring the binding effect of the pin 123 and ensuring the ultimate reliability of the display module.

[0064] The circuit board involved in the embodiment of the present disclosure is described in detail below with reference to specific examples.

[0065] like Figure 4 and Figure 5 As shown, the circuit board includes a circuit board body 1, which has a routing area 101, a transition area 102 and a pin area 101 arranged in sequence along a first direction, and the transition area 102 is arranged between the routing area 101 and the pin area 101, and is connected to the routing area 101 and the pin area 101 respectively.

[0066] The circuit board body 1 includes a substrate 11 and a first conductive layer 12, wherein the first conductive layer 12 is disposed on one side of the substrate 11. The first conductive layer 12 includes a circuit trace 121, a plurality of adapter wires 122, and a plurality of pins 123, wherein the circuit trace 121 is located in a trace area 101, a plurality of pins 123 are located in a pin area 101, and a plurality of adapter wires 122 are located in a transition area 102.

[0067] Multiple pins 123 are arranged parallel to each other along the first direction, multiple adapter wires 122 are arranged parallel to each other along the first direction, and each adapter wire 122 is respectively connected to the circuit trace 121 and multiple pins 123. It can be understood that each adapter wire 122 is arranged on the same layer as the circuit trace 121 and the pins 123.

[0068] The circuit board body 1 also includes a protective layer 13, which is arranged on the side of the first conductive layer 12 away from the substrate 11. The protective layer 13 is located in the wiring area 101. The protective layer 13 is a patterned coating, and the patterned coating has a device area, which is coated on the circuit wiring 121 and the substrate 11 that are not needed, in order to protect the formed circuit pattern for a long time. The protective layer 13 is usually provided with a hollow portion in the device area, and the hollow portion exposes part of the circuit wiring 121 as a welding portion, and the electronic components are welded on the welding portion. It should be noted that the protective layer is usually set as green oil.

[0069] The circuit board also includes a protective layer 2, which is coated on the side of the protective layer 13 away from the substrate 11. The protective layer 2 can be made of three-proof paint, which is usually a transparent UV curing glue. After curing, the three-proof paint forms a transparent protective film with excellent insulation, moisture-proof, anti-leakage, shock-proof, dust-proof, anti-corrosion, anti-aging, and corona resistance. In particular, it has good moisture-proof, salt spray-proof, and mildew-proof properties, which is the three-proof of the three-proof paint. The three-proof paint can be a fluorescent three-proof paint, which shows blue under ultraviolet light, which is convenient for controlling the coating accuracy of the protective layer 2.

[0070] The liquid protective layer 2 flows along the wiring area 101 to the pin area 101. When the liquid protective layer 2 seeps into the pin area 101, it will cause poor binding of the pin 123. Therefore, the circuit board also includes a blocking dam 3, which covers the side of the protective layer 13 close to the pin area 101. The height difference between the side of the blocking dam 3 away from the substrate 11 and the side of the protective layer 13 away from the substrate 11 can prevent the liquid protective layer 2 from reaching the edge of the pin area 101.

[0071] The adapter wire 122 is raised relative to the base 11, so a groove 124 is formed between two adjacent adapter wires 122, and multiple parallel grooves 124 are formed between multiple adapter wires 122, which are equivalent to capillaries. The liquid protective layer 13 in the narrow space such as the groove 124 can make the liquid that is wet or non-wet with the groove wall generate a capillary force pointing to the concave liquid surface. When the liquid protective layer 13 is coated or splashed onto the edge of the adapter wire 122, due to the capillary surface tension, the flowable protective layer 13 will penetrate and flow along the groove 124 to the pin area 101, and even penetrate the entire pin area 101. The blocking dam 3 at least fills one end of each groove 124 close to the routing area 101, which can prevent the liquid protective layer 2 from seeping into the pin area 101 due to capillary action.

[0072] In this embodiment, the barrier dam 3 covers the side of the protective layer 13 close to the pin area 101, the barrier dam 3 covers the adapter line 122, and the barrier dam 3 overlaps with one end of the pin 123 close to the adapter line 122. The overlapping width of the barrier dam 3 and the pin 123 is less than one-fifth of the length of the pin 123, otherwise it will interfere with the binding of the pin 123 and affect the binding yield of the circuit board. There is no specific restriction on the overlapping width of the barrier dam 3 and the protective layer 13, and the barrier dam 3 does not need to contact the device area. For example, when the length of the pin 123 along the first direction is 2500um, the overlapping width of the barrier dam 3 and the pin 123 cannot exceed 500um.

[0073] The circuit board may also include a first filling layer and a silk-screen layer. The first filling layer is usually used to fill the through holes on the circuit board to improve the flatness of the circuit board, and the silk-screen layer is used to print various logos. The silk-screen layer is arranged on the first filling layer. When forming the silk-screen layer, there must be a film layer so that no additional process and cost are added to the first filling layer. It should be noted that the material of the first filling layer can usually be resin, and the silk-screen layer can usually be white paint. The blocking dam 3 can be formed of the same layer and material as the first filling layer, because the thickness of the first filling layer can be made relatively thick, which is convenient for adjusting the thickness of the first filling layer. In addition, there is no need to form the blocking dam 3 separately, which can save a process.

[0074] like Figures 6 to 9 As shown, the blocking dam 3 may also include a first blocking layer 31 and a second blocking layer 32. The first blocking layer 31 and the second blocking layer 32 are arranged in sequence along the direction away from the circuit board body 1. The second blocking layer 32 is close to the edge of the protective layer 2 and may be closer to the pin area 101 than the edge of the first blocking layer 31 is close to the protective layer 2. The second blocking layer 32 is away from the edge of the protective layer 2 and may be farther from the pin area 101 than the edge of the first blocking layer 31 is away from the protective layer 2.

[0075] The orthographic projection of the second barrier layer 32 on the substrate 11 is located within the orthographic projection of the first barrier layer 32 on the substrate 11. It can be understood that the two sides of the second barrier layer 32 extending in the second direction are both retracted in the first direction relative to the two sides of the first barrier layer 31 extending in the second direction, so the width of the second barrier layer 32 is smaller than the width of the first barrier layer 31, so that the barrier dam 3 forms a step shape. When the barrier dam 3 has the same height, compared Figure 4 and Figure 5 In the structure in which only the first barrier layer 31 is provided, it is more difficult for the flowing protective layer 2 to pass over the stepped barrier dam 3, requiring a larger volume of barrier layers and more distance to climb.

[0076] It should be noted that the second direction is perpendicular to the first direction. Figure 7 and Fig. 9 The x direction in the second direction is Figure 7 and Fig. 9 y direction in .

[0077] like Figure 6 and Figure 7 As shown, in one embodiment, the first barrier layer 31 can be formed of the same layer and material as the first filling layer, and the second barrier layer 32 can be formed of the same layer and material as the silk-screen layer. Figure 8 and Fig. 9 As shown, in another embodiment, the circuit board further includes a second filling layer, the first barrier layer 31 can be formed of the same layer and material as the filling layer, and the second barrier layer 32 can be formed of the same layer and material as the second filling layer.

[0078] The material of the first filling layer and the material of the second filling layer can both be set to resin. When making the double-layer resin barrier dam 3, two layers of steel mesh layers can be used, and the first filling layer and the second filling layer can be coated on the two layers of steel mesh layers respectively. The first filling layer and the second filling layer can also be coated in sequence by inkjet printing.

[0079] In order to further prevent the liquid protective layer from flowing to the pin area, the side of the barrier dam 3 away from the substrate 11 can also be set as a rough surface. Specifically, the rough surface can be provided with a plurality of wavy barrier patterns on the side of the barrier dam 3 away from the substrate 11. The wavy barrier patterns are arranged at intervals along the first direction, and any two adjacent wavy barrier patterns are parallel to each other in the second direction. The rough surface can also be provided with a plurality of array-arranged bumps on the side of the barrier dam 3 away from the substrate 11.

[0080] like Fig.10As shown, the circuit board body 1 includes a substrate 11, an insulating layer 14, a first conductive layer 12, a second conductive layer and a protective layer 13. The second conductive layer is arranged on one side of the substrate 11, the insulating layer 14 is arranged on a side of the second conductive layer away from the substrate 11, the first conductive layer 12 is arranged on a side of the insulating layer 14 away from the substrate 11, and the protective layer 13 is arranged on a side of the first conductive layer 12 away from the substrate 11.

[0081] The first conductive layer 12 includes a circuit trace 121 and a plurality of pins 123. The circuit trace 121 is located in the trace area 101. The plurality of pins 123 are located in the pin area 101. The plurality of pins 123 are arranged parallel to each other along a first direction. The second conductive layer includes a plurality of adapter wires 122. The plurality of adapter wires 122 are arranged parallel to each other along a first direction. One end of the orthographic projection of the adapter wire 122 on the substrate 11 overlaps with the orthographic projection of the circuit trace 121 on the substrate 11. The other end of the orthographic projection of the adapter wire 122 on the substrate 11 overlaps with the orthographic projection of the pin 123 on the substrate 11. The pin 123 is connected to the adapter wire 122 through a first via 141. The circuit trace 121 is connected to the adapter wire 122 through a second via 142.

[0082] The patterned protective layer 13 is located in the routing area 101, covering the side of the circuit routing 121 away from the substrate 11. The blocking dam 3 covers the side of the protective layer 13 close to the pin area 101, and along the side of the protective layer 13 and the circuit routing 121 close to the pin area 101, covers the area where the insulating layer 14 is located in the transition area 102. The blocking dam 3 can also extend from the insulating layer 14 to the pin 123. The overlapping width of the blocking dam 3 and the pin 123 is less than one-fifth of the length of the pin 123. There is no specific limitation on the overlapping width of the blocking dam 3 and the protective layer 13, and the blocking dam 3 does not need to contact the device area.

[0083] The pins 123 and the adapter wires 122 are respectively arranged on the first conductive layer 12 and the second conductive layer, and the insulating layer 14 can fill the groove 124 formed between two adjacent adapter wires 122. In the case where the barrier dam 3 does not completely cover the area of ​​the insulating layer 14 located in the transition zone 102, even if the liquid protective layer 2 passes over the barrier dam 3, it will seep to the surface of the insulating layer 14, which can avoid the situation where the capillary force causes the liquid protective layer 2 to move and seep toward the pins 123.

[0084] like Fig.11As shown, the adapter 122 is extended to the device area along the first direction, so that the orthographic projection of the adapter 122 on the substrate 11 overlaps with the device area to form an overlapping area 1011, and the orthographic projection of the second via 142 on the substrate 11 is located in the overlapping area 1011. The circuit trace 121 is connected to the adapter 122 through the second via 142, and the orthographic projection of the second via 142 on the substrate 11 is located on the side of the overlapping area 1011 away from the pin 123 area 101. The distance between the second via 142 and the first via 141 can be increased to reduce the electromagnetic interference generated during the signal transmission process.

[0085] like Fig.12 As shown, different circuit traces 121 are connected to different pins 123 through different second vias 142, and the orthographic projections of at least some of the second vias 142 in the first direction do not overlap. If the space in the first direction allows, the orthographic projections of all the second vias 142 in the first direction can be set to be non-overlapping. It can be understood that this will increase the distance between two adjacent second vias 142, reduce the setting density of the second transfer holes, and further reduce the electromagnetic interference generated during signal transmission.

[0086] like Fig.13 As shown, the protective layer 13 covers one end of the circuit trace 121 close to the pin area 101, and is at least partially located in the transition area 102. It should be noted that the protective layer 13 cannot cover the pin 123. The protective layer 13 can support the blocking dam 3 and increase the height of the blocking dam 3. The protective layer 2 has the same coating thickness, so that the top of the blocking dam 3 can block the thicker liquid protective layer 2. In other embodiments, the protective layer 13 can be arranged in the trace area 101 and does not overlap with the blocking dam 3.

[0087] like Fig.14 As shown, in order to improve the blocking effect of the blocking dam 3 on the liquid protective layer 2, the blocking dam 3 is arranged to be gradually inclined away from the pin area 101 along the direction away from the circuit board body 1. In the process of the liquid protective layer 2 overflowing in the direction of the pin area 101, the liquid protective layer 2 can be accommodated in an increased amount, and the resistance to the overflow of the liquid protective layer 2 can also be increased, thereby improving the blocking effect of the blocking dam 3. Fig.15 As shown, in other feasible embodiments, the barrier dam 3 may also be arranged to be gradually inclined in a direction away from the circuit board body 1 and toward a direction close to the pin area 101 .

[0088] like Fig.16As shown, in order to improve the blocking effect of the blocking dam 3 on the liquid anti-slip layer, a guide groove 301 can be set on the side of the blocking dam 3 close to the wiring area 101, and the guide groove 301 can extend to the edge of the blocking dam 3 along the second direction, and the second direction is perpendicular to the first direction. The guide groove 301 can be set on the side close to the blocking dam 3 away from the substrate 11. When the coating height of the liquid protective layer 2 reaches a certain height, the excess liquid protective layer 2 is guided away through the guide groove 301, while ensuring the protective effect, the probability of the liquid protective layer 2 crossing the blocking dam 3 can be reduced. In order to improve the diversion effect, multiple guide grooves 301 can be set in the direction away from the substrate 11.

[0089] like Fig.17 As shown, when the blocking dam 3 includes a first blocking layer 31 and a second blocking layer 32, the first blocking layer 31 and the second blocking layer 32 can be set to be gradually inclined from a direction away from the circuit board body 1 to a direction away from the pin area 101, and the guide groove 301 can be set on a side of the second blocking layer 32 close to the routing area 101, and the bottom surface of the guide groove 301 can be set to be parallel to the inclined surface of the second blocking layer 32.

[0090] like Fig.18 As shown, when the liquid protective layer 2 passes over the barrier dam 3 and flows into the groove 124, in order to prevent the liquid protective layer 2 from seeping into the pin area 101 under the action of capillary force and affecting the binding effect of the pin 123. Fig.19 As shown, at least one buffer section 1241 of the groove 124 is formed between two adjacent adapter wires 122, and the width of the buffer section 1241 is greater than the distance between two adjacent pins 123, that is, in the transition zone 102, the line width of at least part of the adapter wire 122 is narrowed, so that the distance between adjacent adapter wires 122 becomes larger in the narrowed section.

[0091] like Fig. 20 As shown, in order to further reduce the effect of capillary force, the width of the buffer section 1241 is set to gradually increase in the direction close to the pin area 101. Fig.21 As shown, in order to facilitate processing of the buffer section 1241 on the groove 124, the width of the buffer section 1241 can also be set to gradually increase and then gradually decrease along the direction close to the pin area 101. Fig. 22 As shown, in order to ensure the reliability of the transfer line 122, the edge of the buffer section 1241 can also be made into an arc shape. It should be noted that the shapes mentioned above are included but not limited to the above shapes, as long as they can gradually reduce the capillary force in the direction close to the pin area 101.

[0092] like Fig.23As shown, a plurality of buffer segments 1241 are formed between two adjacent adapter lines 122, and the width of the plurality of buffer segments 1241 gradually increases in the direction close to the pin area 101. Along the flow direction of the liquid protective layer 2, each buffer segment 1241 can play a role in weakening the capillary force. And the effect of each buffer segment 1241 in weakening the capillary force gradually increases in the direction close to the pin area 101. By performing multi-stage reduction of the capillary force through a plurality of buffer segments 1241 of different sizes, the probability of the liquid protective layer 2 invading the pin area 101 can be further reduced. It should be noted that the buffer segment 1241 is not limited to the rectangular structure shown in the figure, and can also adopt the above-mentioned width discontinuous structure along the first direction.

[0093] like Fig.24 As shown, the advantage of such a design is that, according to the mechanism of capillary force, the capillary force points to the direction of the concave surface of the liquid, and its magnitude is proportional to the surface tension of the liquid and inversely proportional to the radius R of the capillary, that is, the smaller the radius R, the stronger the capillary force, and vice versa. Fig.13 As shown, the radius of the capillary in the buffer section 1241 is defined as R2, and the radius of the other sections of the groove 124 is defined as R1, R2 is significantly larger than R1, and after the width of the adapter 122 is narrowed, as the liquid protective layer 2 flows toward the pin area 101, the width of the groove 124 in the buffer section 1241 becomes larger, and as the radius R of the capillary gradually increases, the capillary force gradually weakens, which can effectively reduce the probability of the liquid protective layer 2 invading the pin area 101 due to the capillary force.

[0094] The embodiments of the present disclosure also provide a display module. The display module may include a circuit board and a display panel involved in any one of the embodiments of the present disclosure, wherein the circuit board is usually attached to a non-display surface of the display panel and is bound together with a flexible circuit board connected to the display panel, or is directly bound and connected to a flexible display panel having a bendable area.

[0095] The embodiment of the present disclosure also provides a display device. The display device may include the display module involved in the embodiment of the present disclosure. The specific structure and beneficial effects of the display module have been described in detail above, so they will not be repeated here.

[0096] It should be noted that, in addition to the display module, the display device also includes other necessary parts and components, such as a housing, a power cord, etc. Those skilled in the art may make corresponding supplements according to the specific use requirements of the display device, which will not be elaborated here.

[0097] When the flexible circuit board is of the structure shown in the figure, the display device can be a traditional electronic device, such as a mobile phone, a computer, a television, and a camcorder, or it can be an emerging wearable device, such as a virtual reality device and an augmented reality device, which are not listed here one by one.

[0098] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the appended claims.

Claims

1. A circuit board, characterized in that: include: A circuit board body, the circuit board body comprising a routing area and a pin area sequentially spaced apart along a first direction; A protective layer is provided on one side of the circuit board body, the protective layer covers the wiring area, and the protective layer flows along the wiring area toward the pin area before solidification; The blocking dam and the protective layer are arranged on the same side of the circuit board body, the blocking dam covers one end of the routing area close to the pin area, and the blocking dam can form a barrier to the flowing protective layer.

2. The circuit board according to claim 1, characterized in that: The barrier dam includes a first barrier layer and a second barrier layer sequentially arranged in a direction away from the circuit board body, wherein an edge of the second barrier layer adjacent to the protective layer is closer to the pin area than an edge of the first barrier layer adjacent to the protective layer.

3. The circuit board according to claim 1, characterized in that: A guide groove is provided on one side of the blocking dam close to the routing area. The guide groove is arranged along a second direction and extends to an edge of the blocking dam. The second direction is perpendicular to the first direction.

4. The circuit board according to claim 1, characterized in that: The blocking dam is gradually inclined in a direction away from the circuit board body and away from the pin area.

5. The circuit board according to claim 1, characterized in that: The circuit board body includes a substrate and a first conductive layer, the first conductive layer includes a plurality of pins, the plurality of pins are located in the pin area and are arranged parallel to each other along the first direction, the first conductive layer also includes a circuit trace, the circuit trace is located in the trace area, a transition area is provided between the trace area and the pin area, the transition area is provided with a plurality of parallel adapter wires along the first direction, each of the adapter wires is respectively connected to the circuit trace and the plurality of pins.

6. The circuit board according to claim 5, characterized in that: The adapter wires are arranged in the same layer as the circuit wiring and the pins, a groove is formed between two adjacent adapter wires, and the blocking dam at least fills one end of each groove close to the wiring area.

7. The circuit board according to claim 5, characterized in that: The circuit board also includes an insulating layer, which is arranged between the substrate and the first conductive layer. The adapter is arranged between the insulating layer and the substrate. The pin is connected to the adapter through a first via hole, and the circuit trace is connected to the adapter through a second via hole.

8. The circuit board according to claim 7, characterized in that: The orthographic projection of the adapter wire on the substrate overlaps with the orthographic projection of the circuit trace on the substrate to form an overlapping area, and the orthographic projection of the second via on the substrate is located in the overlapping area.

9. The circuit board according to claim 8, characterized in that: The orthographic projection of the second via hole on the substrate is located on a side of the overlapping region away from the pin region.

10. The circuit board according to claim 8 or 9, characterized in that: Different circuit traces are connected to different pins through different second vias, and orthographic projections of at least some of the second vias in the first direction do not overlap.

11. The circuit board according to claim 6, characterized in that: At least one buffer section is formed between two adjacent transfer lines, and the width of the buffer section is greater than the distance between two adjacent pins.

12. The circuit board according to claim 11, characterized in that: The width of the buffer section gradually increases along a direction approaching the pin area.

13. The circuit board according to claim 11, characterized in that: The width of the buffer section gradually increases and then gradually decreases along a direction approaching the pin area.

14. The circuit board according to claim 13, characterized in that: The edge of the buffer section has an arc-shaped contour.

15. The circuit board according to claim 11, characterized in that: A plurality of buffer sections are formed between two adjacent transfer lines, and the widths of the plurality of buffer sections gradually increase in a direction approaching the pin area.

16. The circuit board according to claim 6 or 7, characterized in that: A patterned protective layer is provided on the side of the circuit routing away from the substrate, the protective layer is located in the routing area, the blocking dam covers the side of the protective layer close to the pin area, the routing area includes a device area away from the pin area, and the blocking dam does not contact the device area.

17. The circuit board according to claim 16, characterized in that: The protection layer covers one end of the circuit trace close to the pin area and is at least partially located in the transition area.

18. The circuit board according to claim 7, characterized in that: The barrier dam at least partially covers a region of the insulating layer located in the transition region.

19. The circuit board according to claim 6, characterized in that: The barrier dam covers the patch cord.

20. The circuit board according to claim 18 or 19, characterized in that: The blocking dam overlaps with an end of the pin close to the adapter wire, and the overlapping width of the blocking dam and the pin is less than one fifth of the length of the pin.

21. The circuit board according to claim 1, characterized in that The protective layer is a triple-proof paint.

22. A display module, characterized in that: It comprises a display panel and a circuit board which are electrically connected, wherein the circuit board is the circuit board according to any one of claims 1 to 19.

23. A display device, characterized in that: Includes the display module described in claim 20.

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