Circuit soft board with heat dissipation function and light emitting module

Abstract

The application discloses a circuit soft board with a heat dissipation function and a light-emitting module, and relates to the technical field of circuit soft boards. The circuit soft board comprises a base material layer, a circuit layer, a solder pad and a soft board component. The vertical projection of the solder pad in the base material layer is located in the bending part. The vertical projection of the soft board component in the base material layer is located in the heat dissipation part. The solder pad is connected with the soft board component through a wire in the circuit layer. The heat dissipation part comprises a first heat dissipation layer, a second heat dissipation layer and a heat resistance layer located between the first heat dissipation layer and the second heat dissipation layer. The first heat dissipation layer is arranged in the same layer as the bending part. The heat dissipation part is used for blocking the mutual conduction of the heat generated by the to-be-bound device and the soft board component, and dissipating the heat generated by the to-be-bound device and the soft board component, so that the stability of the soft board structure and the service life of the to-be-bound device are improved.

Description

Technical Field

[0001] The present invention relates to the field of flexible circuit board technology, and in particular to a flexible circuit board with heat dissipation function and a light-emitting module. Background Technology

[0002] With the rapid development of electronic products, there are many types of circuit boards, including rigid boards, flexible boards, and rigid-flex boards. Among them, flexible printed circuits (FPCs) have advantages such as high wiring density, light weight, thinness, flexibility, and high flexibility, which are unmatched by other types of circuit boards.

[0003] Currently, flexible circuit boards (FPCBs) are made of flexible substrates such as polyimide or polyester film. After the FPCB is bonded to the device to be bonded, such as to an organic light-emitting diode (OLED) screen, the heat dissipation efficiency of the device is reduced because the FPCB covers the device or is close to it. Furthermore, the heat generated by the device to be bonded is conducted to the FPCB, affecting the structural stability of the FPCB. In addition, when the components integrated on the FPCB generate a lot of heat, the inability of the FPCB to dissipate heat effectively will also affect the stability of the FPCB structure. The heat generated by the components is conducted to the device to be bonded, causing the device to overheat and affecting its lifespan. Therefore, how to prevent the heat generated by the device to be bonded and the components from being conducted to each other, and how to dissipate the heat generated by the devices to be bonded and the components, has become an urgent technical problem to be solved. Summary of the Invention

[0004] This invention provides a flexible circuit board and a light-emitting module with heat dissipation function to prevent heat generated by the devices and components to be bonded from being conducted to each other, and to dissipate heat generated by the devices and components to be bonded, thereby ensuring the working characteristics of the devices.

[0005] According to one aspect of the present invention, a flexible circuit board with heat dissipation function is provided, comprising:

[0006] The substrate layer includes a heat dissipation portion and a bending portion, wherein the heat dissipation portion is adjacent to the bending portion;

[0007] A circuit layer located on the side of the substrate layer and / or inside the substrate layer;

[0008] The pads and flexible circuit board components are provided, wherein the vertical projection of the pads in the substrate layer is located in the bend; the pads are connected to the flexible circuit board components through the circuit layer.

[0009] The heat dissipation unit includes: a first heat dissipation layer, a second heat dissipation layer, and a heat-insulating layer located between the first heat dissipation layer and the second heat dissipation layer; the heat dissipation unit is used to prevent the heat generated by the device to be bonded and the flexible circuit board components from being conducted to each other, and to dissipate the heat generated by the device to be bonded and the flexible circuit board components.

[0010] Optionally, the first heat dissipation layer and / or the second heat dissipation layer include multiple hollow structures, which are used to increase the heat dissipation area of ​​the heat dissipation layer.

[0011] Optionally, the cutout pattern of the cutout structure includes at least one of polygons, circles, and ellipses.

[0012] Optionally, the first heat dissipation layer includes a first heat dissipation substrate in contact with the surface of the circuit layer, and a plurality of first heat dissipation fins fixed between the first heat dissipation substrate and the heat insulation layer, wherein the cavity formed between two adjacent first heat dissipation fins serves as the hollow structure.

[0013] The second heat dissipation layer includes a second heat dissipation substrate in contact with the surface of the device to be bonded, and a plurality of second heat dissipation fins fixed between the second heat dissipation substrate and the heat insulation layer. The cavity formed between two adjacent second heat dissipation fins serves as the hollow structure.

[0014] Optionally, the plane on which the first heat sink is located is perpendicular to the plane on which the first heat sink substrate is located; the planes on which each first heat sink is located are parallel to each other; and multiple first heat sinks are arranged sequentially at intervals.

[0015] And / or, the plane on which the second heat sink is located is perpendicular to the plane on which the second heat sink substrate is located; the planes on which each second heat sink is located are parallel to each other; and a plurality of second heat sinks are arranged at intervals in sequence.

[0016] Optionally, the plane where the first heat sink is located intersects with the plane where the heat dissipation substrate is located; the planes where two adjacent first heat sinks are located intersect each other; multiple first heat sinks are arranged in a crisscross pattern to form multiple heat dissipation support frames;

[0017] And / or, the plane where the second heat sink is located intersects with the plane where the heat sink substrate is located; the planes where two adjacent second heat sinks are located intersect each other; multiple second heat sinks are arranged in a cross pattern to form multiple heat dissipation support frames.

[0018] Optionally, the material of the first heat dissipation layer includes metal; the material of the second heat dissipation layer includes metal; and the material of the heat-insulating layer includes at least one of aerogel and ceramic.

[0019] Optionally, the first heat dissipation layer and / or the second heat dissipation layer may include a flexible carbon nanotube adhesive sheet.

[0020] Optionally, along the direction from the device to be bonded to the circuit layer, the thermal conductivity of the heat dissipation part gradually decreases to a first preset value and then gradually increases to a second preset value; wherein the first preset value is less than the second preset value.

[0021] According to another aspect of the present invention, a light-emitting module is provided, including a light-emitting panel and a flexible circuit board with heat dissipation function as described in any embodiment of the present invention. The flexible circuit board is disposed on the non-light-emitting side of the light-emitting panel, and the pads on the flexible circuit board are bonded to the bonding area of ​​the light-emitting panel.

[0022] Optionally, the light-emitting module also includes:

[0023] A first graphene film is located on the side of the light-emitting panel closest to the flexible circuit board.

[0024] The second graphene film is located on the side of the flexible circuit board component away from the circuit layer.

[0025] The technical solution provided by this invention combines a flexible substrate layer with a heat dissipation structure to dissipate heat from components on the flexible circuit board and from the components to be bonded, while also supporting the components. The heat dissipation structure, combined with the PI film, does not affect the bending performance of the flexible circuit board. The heat dissipation structure comprises three parts: a first heat dissipation layer, a second heat dissipation layer, and a heat-resistant layer located between the first and second heat dissipation layers. The first heat dissipation layer is disposed on the same layer as the bending portion, and the second heat dissipation layer is located between the heat-resistant layer and the components to be bonded, and is in contact with the components to be bonded. The first and second heat dissipation layers have high heat dissipation coefficients, which can effectively dissipate heat from the components on the flexible circuit board and the components to be bonded. The heat resistance layer has a low thermal conductivity, which can prevent the heat generated by the components to be bonded from being transferred to the circuit layer, and also prevent the heat generated by the components on the flexible circuit board from being transferred to the components to be bonded. By controlling the heat between the heat-resistant layer and the heat dissipation layer, the heat is conducted to the environment, reducing the heat conducted to the circuit board, thereby improving the stability of the flexible circuit board structure; and reducing the heat conducted to the components to be bonded, thereby improving the service life of the components to be bonded.

[0026] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a cross-sectional structural diagram of a flexible circuit board with heat dissipation function provided in an embodiment of the present invention;

[0029] Figure 2 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention.

[0030] Figure 3 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention.

[0031] Figure 4 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention.

[0032] Figure 5 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention.

[0033] Figure 6 yes Figure 5 A cross-sectional schematic diagram of the heat dissipation component in the structure shown.

[0034] Figure 7 This is a cross-sectional structural schematic diagram of another heat dissipation component provided in an embodiment of the present invention;

[0035] Figure 8 This is a cross-sectional structural diagram of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] This invention provides a flexible circuit board with heat dissipation function. Figure 1 This is a cross-sectional view of a flexible circuit board with heat dissipation function provided in an embodiment of the present invention. Figure 2 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention. (Refer to...) Figures 1-2 The flexible circuit board with heat dissipation function includes:

[0039] The substrate layer 10 includes a heat dissipation portion 12 and a bending portion 11, with the heat dissipation portion 12 and the bending portion 11 being adjacent to each other.

[0040] The circuit layer 20 is located on the side of the substrate layer 10 and / or within the substrate layer 10;

[0041] The pads 30 and flexible circuit board components 50 are connected by wires in the circuit layer. The vertical projection of the pads 30 in the substrate layer 10 is located in the bending portion 11, and the vertical projection of the flexible circuit board components 50 in the substrate layer 10 is located in the heat dissipation portion 12. The pads 30 are connected to the flexible circuit board components 50 through wires in the circuit layer, and can be connected to the device 200 to be bonded on one side of the substrate layer 10 under the bending of the bending portion 11.

[0042] The heat dissipation part 12 includes: a first heat dissipation layer 121, a second heat dissipation layer 122, and a heat-insulating layer 123 located between the first heat dissipation layer 121 and the second heat dissipation layer 122; optionally, the first heat dissipation layer 121 is disposed in the same layer as the bending part 11; the heat dissipation part 12 is used to block the heat generated by the device to be bonded 200 and the flexible board component 50 from being conducted to each other, and to dissipate the heat generated by the device to be bonded 200 and the flexible board component 50.

[0043] Specifically, the substrate layer 10 of the flexible circuit board includes a heat dissipation portion 12 and a bending portion 11, with the heat dissipation portion 12 adjacent to the bending portion 11. The bending portion 11 can be formed of any suitable insulating material with flexibility. For example, the flexible substrate can be formed of polymer materials such as polyimide (PI), polycarbonate (PC), polyethersulfone (PES), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyaryl compounds (PAR), or glass fiber reinforced plastic (FRP). The bending portion 11 may include a first bending portion 111 and a second bending portion 112, located on opposite sides of the heat dissipation portion 12. Alternatively, the heat dissipation portion 12 may be located in the central region of the substrate layer 10, with the bending portion 11 surrounding the edge of the heat dissipation portion 12. The circuit layer 20 can be located on the side of the substrate layer 10 or inside the substrate layer 10.

[0044] Flexible circuit board (FPCB) components 50 are integrated on the circuit layer 20. Pads 30 are connected to the FPCB components 50 via wires in the circuit layer 20. After the pads 30 on the FPCB are bonded to the device 200 located on the substrate layer 10 away from the circuit layer 20, communication between the FPCB components 50 and the device 200 can be achieved. The device 200 to be bonded can be, for example, a light-emitting panel, and the FPCB component 50 can be a light-emitting control chip. The light-emitting control chip can send light-emitting control signals to the light-emitting panel through the pads 30 on the FPCB.

[0045] When the circuit layer 20 is located on the side of the substrate layer 10, the heat dissipation portion 12 and the bending portion 11 can provide a flat support surface for the circuit layer 20. (Reference) Figure 1 The circuit layer 20 is illustrated as being located on one side of the substrate layer 10. The circuit layer 20 can be fixed to the surface of one side of the substrate layer 10 using a thermosetting adhesive 40, such as AD adhesive (acrylic hot melt adhesive). The solder pads 30 and flexible circuit board components 50 can be located on different sides of the substrate layer 10, for example... Figure 1 As shown, the pad 30 is located on the side of the substrate layer 10 closer to the device 200 to be bonded, the circuit layer 20 is located on the side of the substrate layer 10 away from the device 200 to be bonded, and the flexible circuit board component 50 is located on the side of the circuit layer 20 away from the substrate layer 10 and is in contact with the circuit layer 20. At this time, the pad 30 can be connected to the circuit layer 20 through the through-hole 26 penetrating the substrate layer 10, thereby achieving conductivity between the pad 30 and the flexible circuit board component 50. Additionally, a protective layer 60 can be formed on the circuit layer 20 located on the side of the substrate layer 10 away from the device 200 to be bonded. The material of the protective layer 60 can be the same as that of the substrate layer 10 to protect the circuit layer 20 and insulate it from the outside environment.

[0046] refer to Figure 2The circuit layer 20 is illustrated as being located on one side of the substrate layer 10, with the pads 30 and flexible circuit board components 50 located on the same side of the substrate layer 10. In this case, the substrate layer 10 serves as a base, providing support. The circuit layer 20 can be a double-sided laminate, a three-layer laminate, a four-layer laminate, or other types of rigid-flex PCBs. For example, Figure 3 The double-sided layered board structure is shown. Circuit layer 20 may include a flexible substrate layer 21, and a first metal layer and a second metal layer located on opposite sides of the flexible substrate layer 21. Pads 30 are located on the side of the first metal layer away from the flexible substrate layer and are in contact with the first metal layer. The first and second metal layers can be connected through through-holes 26 penetrating the flexible substrate layer 21. Metal wires are provided in the through-holes 26, allowing the pads 30 to communicate with the second metal layer for signal transmission. The first metal layer may include a base copper 22 on the surface of the flexible substrate layer 21 and copper plating 23 on the surface of the base copper 22. The second metal layer may include a base copper 24 on the other surface of the flexible substrate layer 21 and copper plating 25 on the surface of the base copper 24.

[0047] The bending portion 11 of the flexible circuit board is made of a flexible substrate such as polyimide or polyester film, which has the advantages of high wiring density, light weight, thinness, bendability, and high flexibility. It can withstand millions of dynamic bends without damaging the wires, and can move and stretch arbitrarily according to spatial layout requirements to achieve three-dimensional assembly. (Reference) Figure 1 The pad 30, which connects to the device to be bonded 200, is located on the side of the bend 11 closest to the device to be bonded 200. When the bend 11 bends downward, it can bring the pad 30 closer to the bonding area 201 of the device to be bonded 200, thereby achieving corresponding contact between the pad 30 and the pad in the bonding area 201. (Reference) Figure 2 A pad 30 is provided at the edge of the circuit layer 20 away from the substrate layer 10; the vertical projection of the pad 30 in the substrate layer 10 is located in the bending portion 11. After the bending portion 11 is bent, it can cause the pad 30 to rotate, so that the pad 30 is bonded to the device 200 located on the side of the substrate layer 10 away from the circuit layer 20. The device 200 to be bonded includes a bonding area 201, and the pads (not shown) in the bonding area of ​​the device 200 to be bonded make contact with the pads 30 on the flexible circuit board. There can be multiple pads in the bonding area of ​​the device 200 to be bonded, and the flexible circuit board can include pads 30 that are bonded one-to-one with the pads in the bonding area of ​​the device 200 to be bonded. The arrangement of the pads 30 on the flexible circuit board is not limited here, and can be set according to the arrangement of the bonding pads in the bonding area of ​​the device to be bonded.

[0048] Additionally, refer to Figure 2The flexible circuit board may also include pads 31 for connecting to external lines. The pads 31 for connecting to external lines are connected to the pads 30 for connecting to the device to be bonded 200 through the circuit layer 20, thereby realizing the connection between the device to be bonded 200 and the external lines, and realizing the transmission of power and signals between the device to be bonded 200 and the external lines.

[0049] The device to be bonded 200 is located on one side of the flexible circuit board, close to or in contact with the substrate layer 10 of the flexible circuit board. To prevent the heat generated by the device to be bonded 200 during operation from being difficult to dissipate due to the coverage of the flexible circuit board, and to prevent the heat generated by the device to be bonded 200 from being transferred to the flexible circuit board and affecting the stability of the flexible circuit board structure, this embodiment of the invention sets the area in the substrate layer 10 that is close to or in contact with the device to be bonded 200 as a heat dissipation part 12 with heat dissipation function. The heat dissipation part 12 includes a first heat dissipation layer 121, a second heat dissipation layer 122, and a heat-insulating layer 123 located between the first heat dissipation layer 121 and the second heat dissipation layer 122; the first heat dissipation layer 121 is disposed in the same layer as the bending portion and is in contact with the circuit layer. The second heat dissipation layer 122 is located between the heat-insulating layer 123 and the device to be bonded 200 and is in contact with the device to be bonded 200. In the substrate layer 10, the thickness of the heat dissipation portion 12 is greater than the thickness of the bending portion 11. The thickness of the first heat dissipation layer 121 can be the same as or greater than the thickness of the bending portion 11. When the thickness of the first heat dissipation layer 121 is greater than the thickness of the bending portion 11, a portion of the thickness of the first heat dissipation layer 121 is exposed, which facilitates heat dissipation.

[0050] The first heat dissipation layer 121 and the second heat dissipation layer 122 can be understood as film layers with high heat dissipation coefficients. The heat dissipation coefficient, generally referring to convective heat transfer, refers to the amount of heat transferred through one square meter area in one hour under stable heat transfer conditions, with units of W / m²K. Setting the film layer in contact with the device to be bonded 200 to have a high heat dissipation coefficient effectively dissipates heat from the device 200. Setting the film layer in contact with the circuit layer 20 to have a high heat dissipation coefficient effectively dissipates heat from the flexible circuit board. The thermal insulation layer 123 can be understood as a film layer with low thermal conductivity. Thermal conductivity refers to the amount of heat transferred through one square meter area in one hour by a 1m thick material under stable heat transfer conditions, with units of W / mK. Thermal conductivity is related to the material's composition, density, moisture content, temperature, and other factors. Materials with lower density have lower thermal conductivity. A film layer with low thermal conductivity is provided between the first heat dissipation layer 121 and the second heat dissipation layer 122. This can prevent the heat generated by the device to be bonded 200 from being transferred to the circuit layer 20, and also prevent the heat generated by the flexible circuit board components 50 from being transferred to the device to be bonded 200. The heat is controlled between the heat-insulating layer 123 and the heat dissipation layer (121 / 122), so that the heat is conducted to the environment, reducing the heat conducted to the flexible circuit board, thereby improving the stability of the flexible circuit board structure; and reducing the heat conducted to the device to be bonded 200, thereby improving the service life of the device to be bonded 200.

[0051] The flexible circuit board with heat dissipation function provided in this embodiment of the invention can dissipate heat from components on the flexible board and the components to be bonded by setting the FPC substrate layer as a flexible substrate and combining it with a heat dissipation structure. It also supports the components and uses the heat dissipation structure as a support to enable the components to be soldered on the flexible board. This solves the problem in the prior art that flexible boards made of thermosetting pure adhesive cannot be soldered. Moreover, the combination of the heat dissipation structure and flexible films such as PI does not affect the bending performance of the flexible board. The heat dissipation structure comprises three parts: a first heat dissipation layer, a second heat dissipation layer, and a heat-insulating layer located between the first and second heat dissipation layers. The first heat dissipation layer is disposed on the same layer as the bending portion, and the second heat dissipation layer is located between the heat-insulating layer and the device to be bonded, and is in contact with the device to be bonded. The first and second heat dissipation layers have high heat dissipation coefficients, which can effectively dissipate heat from the components on the flexible circuit board and the device to be bonded. The heat insulation layer has a low thermal conductivity, which can prevent the heat generated by the device to be bonded from being transferred to the circuit layer, and prevent the heat generated by the components on the flexible circuit board from being transferred to the device to be bonded. By controlling the heat between the heat insulation layer and the heat dissipation layer, the heat is conducted to the environment, reducing the heat conducted to the flexible circuit board, thereby improving the stability of the flexible circuit board structure; and by reducing the heat conducted to the device to be bonded, thereby improving the service life of the device to be bonded.

[0052] Optionally, the surface shape of the heat sink 12 in contact with the device to be bonded 200 can be set according to the surface shape of the device to be bonded 200. (See reference) Figures 1-2 When the surface of the device to be bonded 200 is a plane, the surface of the heat dissipation part 12 that contacts the device to be bonded 200 is also a plane. Figure 3 This is a cross-sectional view of another flexible circuit board with heat insulation function provided in an embodiment of the present invention. (Refer to...) Figure 3 When the surface of the device to be bonded 200 is curved, the surface of the heat sink 12 that contacts the device to be bonded 200 is also curved. This allows the heat sink 12 to be tightly fitted to the light-emitting panel. This ensures that the entire power amplifier area of ​​the device to be bonded 200 can contact the heat sink 12, increasing the contact area between the heat sink 12 and the device to be bonded 200, improving the heat dissipation efficiency of the device to be bonded 200, and simultaneously improving the heat dissipation uniformity of the device to be bonded 200.

[0053] Figure 4 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention. (Refer to...) Figure 4 Based on the above embodiments, as one implementation of the present invention, optionally, the first heat dissipation layer 121 and / or the second heat dissipation layer 122 include a plurality of hollow structures 124, the hollow structures 124 being used to increase the heat dissipation area of ​​the heat dissipation layer. Figure 4 The first heat dissipation layer 121 and the second heat dissipation layer 122 are illustrated by way of example, both of which include multiple hollow structures 124.

[0054] Specifically, the perforated structure 124 can be understood as an opening formed in the horizontal direction of the heat dissipation layer (first heat dissipation layer 121 and / or second heat dissipation layer 122) that penetrates the heat dissipation layer. Etching multiple perforated structures 124 in the heat dissipation layer can increase the contact area between the heat dissipation layer and the external environment, i.e., increase the heat dissipation area of ​​the heat dissipation layer, thereby improving the heat dissipation efficiency of the heat dissipation layer. The perforated pattern of the perforated structure 124 includes at least one of polygons, circles, ellipses, and pentagrams, and can also be other shapes.

[0055] Figure 5 This is a cross-sectional view of another flexible circuit board with heat dissipation function provided in an embodiment of the present invention. Figure 6 yes Figure 5 A cross-sectional view of the heat dissipation component in the structure shown is provided for reference. Figure 5 and Figure 6 Based on the above embodiments, as an implementation of the present invention, optionally, the first heat dissipation layer 121 includes a first heat dissipation substrate 1211 in contact with the surface of the circuit layer, and a plurality of first heat dissipation fins 1212 fixed between the first heat dissipation substrate 1211 and the heat insulation layer 123, and the cavity formed between two adjacent first heat dissipation fins 1212 is used as a hollow structure 124.

[0056] Specifically, the first heat dissipation substrate 1211 in contact with the surface of the circuit layer 20 is a full-length film layer, ensuring that the entire circuit layer can contact the first heat dissipation substrate 1211. This increases the contact area between the first heat dissipation substrate 1211 and the circuit layer 20, improving the heat dissipation efficiency of the circuit layer 20 and the flexible circuit board components 50 on it, while also improving the heat dissipation uniformity of the circuit layer and the flexible circuit board components 50 on it. Furthermore, both opposing surfaces of each first heat sink 1212 are in contact with the external environment, further increasing the heat dissipation area of ​​the first heat dissipation layer 121 and improving its heat dissipation efficiency. It also reduces the heat transferred from the first heat dissipation layer 121 to the heat-insulating layer 123, controlling the heat between the heat-insulating layer 123 and the first heat dissipation layer 121, allowing the heat to be conducted into the environment, reducing the heat transferred to the device to be bonded 200, and improving the lifespan of the device to be bonded 200. The first heat sink 1212 and the first heat sink substrate 1211 can be made of the same material and can be formed by etching a material layer, which can improve the firmness between the first heat sink 1212 and the first heat sink substrate 1211.

[0057] Please continue to refer to this. Figure 5 and Figure 6 Based on the above embodiments, as an implementation of the present invention, optionally, the second heat dissipation layer 122 includes a second heat dissipation substrate 1221 in contact with the surface of the device to be bonded, and a plurality of second heat dissipation fins 1222 fixed between the second heat dissipation substrate 1221 and the heat insulation layer 123, and the cavity formed between two adjacent second heat dissipation fins 1222 is used as a hollow structure 124.

[0058] Specifically, the second heat dissipation substrate 1221, which contacts the surface of the device to be bonded 200, is a single-layer film. The shape of the second heat dissipation substrate 1221 is determined according to the surface shape of the device to be bonded 200 near the flexible circuit board. When the device to be bonded 200 is a light-emitting panel, such as an OLED display, the surface of the light-emitting panel near the flexible circuit board with heat insulation function is flat, and the second heat dissipation substrate 1221 is a flat substrate. If the surface of the light-emitting panel near the flexible circuit board is curved, the second heat dissipation substrate 1221 is a curved substrate, allowing the second heat dissipation substrate 1221 to be tightly fitted to the light-emitting panel. This ensures that the entire power amplifier area of ​​the device to be bonded 200 can contact the second heat dissipation substrate 1221, increasing the contact area between the second heat dissipation substrate 1221 and the device to be bonded 200, improving the heat dissipation efficiency of the device to be bonded 200, and simultaneously improving the heat dissipation uniformity of the device to be bonded 200. Furthermore, both opposing surfaces of each second heat sink 1222 are in contact with the external environment, thereby further increasing the heat dissipation area of ​​the second heat dissipation layer 122 and improving its heat dissipation efficiency. This also reduces the heat transferred from the second heat dissipation layer 122 to the heat-insulating layer 123, confining the heat between the heat-insulating layer 123 and the second heat dissipation layer 122, allowing the heat to be conducted into the environment, reducing the heat transferred to the flexible circuit board, and improving the stability of the flexible circuit board structure. The second heat sink 1222 and the second heat dissipation substrate 1221 can be made of the same material, formed by etching a single material layer, which improves the bonding strength between the second heat sink 1222 and the second heat dissipation substrate 1221.

[0059] Please continue to refer to this. Figure 5 and Figure 6 Optionally, the plane of the first heat sink 1212 is perpendicular to the plane of the first heat sink substrate 1211; the planes of each first heat sink 1212 are parallel to each other; and multiple first heat sinks 1212 are arranged at intervals in sequence.

[0060] And / or, the plane on which the second heat sink 1222 is located is perpendicular to the plane on which the second heat sink substrate 1221 is located; the planes on which each second heat sink 1222 is located are parallel to each other; and a plurality of second heat sinks 1222 are arranged at intervals in sequence.

[0061] Specifically, multiple first heat sinks 1212 can be arranged in parallel between the first heat dissipation substrate 1211 and the heat insulation layer 123. The cavity formed between two adjacent first heat sinks 1212 is rectangular, that is, the shape of the hollow structure 124 is rectangular. Setting the plane where the first heat sink 1212 is located is perpendicular to the plane where the first heat dissipation substrate 1211 is located. The first heat sink 1212 is inclined in one direction between the first heat dissipation substrate 1211 and the heat insulation layer 123, which can improve the support of the first heat dissipation layer 121.

[0062] Multiple second heat sinks 1222 can be arranged in parallel between the second heat dissipation substrate 1221 and the heat insulation layer 123. The cavity formed between two adjacent second heat sinks 1222 is rectangular, that is, the shape of the hollow structure 124 is rectangular. The plane on which the second heat sink 1222 is located is perpendicular to the plane on which the second heat dissipation substrate 1221 is located. The second heat sink 1222 is inclined relative to the second heat sink 1222 in one direction between the second heat dissipation substrate 1222 and the heat insulation layer 123, which can improve the support of the second heat dissipation layer 122.

[0063] Figure 7 This is a cross-sectional structural diagram of another heat insulation part provided in an embodiment of the present invention, for reference. Figure 7 In one embodiment of the present invention, optionally, the plane where the first heat sink 1212 is located intersects the plane where the first heat sink substrate 1211 is located; the planes where two adjacent first heat sinks 1212 are located intersect each other; and multiple first heat sinks 1212 are arranged in a cross manner to form multiple heat dissipation support frames.

[0064] And / or, the plane where the second heat sink 1222 is located intersects the plane where the second heat sink substrate 1221 is located; the planes where two adjacent second heat sinks 1222 are located intersect each other; multiple second heat sinks 1222 are arranged in a cross manner to form multiple heat dissipation support frames.

[0065] Specifically, the first heat dissipation layer 121 can be understood as including a first heat dissipation substrate 1211 in contact with the surface of the circuit layer, and a plurality of first heat dissipation support frames 1213 fixed between the first heat dissipation substrate 1211 and the heat insulation layer 123. Each first heat dissipation support frame 1213 is formed by the intersection of two adjacent first heat dissipation fins 1212 with different inclination directions. The first heat dissipation fins 1212 include a plurality of heat dissipation fins a inclined along a first direction and a plurality of heat dissipation fins b inclined along a second direction. The first direction intersects the second direction, and the direction perpendicular to the heat dissipation substrate is located between the first direction and the second direction. The heat dissipation fins a inclined along the first direction and the heat dissipation fins b inclined along the second direction are arranged alternately in sequence, and adjacent heat dissipation fins a and b are used to form a first heat dissipation support frame 1213.

[0066] The second heat dissipation layer 122 may include a second heat dissipation substrate 1221 in contact with the surface of the device to be bonded, and a plurality of second heat dissipation support frames 1223 fixed between the second heat dissipation substrate 1221 and the heat insulation layer 123. Each second heat dissipation support frame 1223 is formed by the intersection of two adjacent second heat dissipation fins 1222 with different inclination directions. The second heat dissipation fins 1222 include a plurality of heat dissipation fins c inclined along a third direction and a plurality of heat dissipation fins d inclined along a fourth direction. The third direction intersects the fourth direction, and the direction perpendicular to the second heat dissipation substrate 1221 is located between the third direction and the fourth direction. The heat dissipation fins c inclined along the third direction and the heat dissipation fins d inclined along the fourth direction are arranged alternately in sequence, and adjacent heat dissipation fins c and d are used to form a second heat dissipation support frame 1223.

[0067] The first direction can be the same as the third direction, and the second direction can be the same as the fourth direction. The number of first heat dissipation support frames can be the same as the number of second heat dissipation support frames, and they are arranged in a one-to-one correspondence. In the first heat dissipation layer 121, the sides of heat sinks a and b away from the first heat dissipation substrate 1211 can contact and be fixed, and the sides of heat sinks a and b near the first heat dissipation substrate 1211 are both in contact with and fixed to the first heat dissipation substrate 1211. Heat sinks a, heat sink b, and the first heat dissipation substrate 1211 between heat sinks a and heat sink b can form a hollow triangular prism-shaped first heat dissipation support frame 1213, that is, the cross-sectional shape of the first heat dissipation support frame 1213 is triangular. Based on the stability of triangles, the triangular first heat dissipation support frame 1213 can improve the support of the first heat dissipation layer 121. In the second heat dissipation layer 122, the sides of heat sinks c and d away from the second heat dissipation substrate 1221 can contact and be fixed, while the sides of heat sinks c and d close to the second heat dissipation substrate 1221 are also in contact with and fixed to the second heat dissipation substrate 1221. Heat sinks c and d, and the second heat dissipation substrate 1221 between them, can form a hollow triangular prism-shaped second heat dissipation support frame 1223, meaning the cross-sectional shape of the second heat dissipation support frame 1223 is triangular. Based on the stability of a triangle, the triangular second heat dissipation support frame 1223 can improve the support of the second heat dissipation layer 122. The hollow structure can be triangular or trapezoidal in shape.

[0068] Based on the above embodiments, as one implementation of the present invention, optionally, the material of the first heat dissipation layer 121 includes metal; the material of the second heat dissipation layer 122 includes metal; and the material of the heat-insulating layer 123 includes at least one of aerogel and ceramic.

[0069] Specifically, the materials of the first heat dissipation layer 121 and the second heat dissipation layer 122 can include metallic materials, such as aluminum, copper, etc. Metallic materials have a high heat dissipation coefficient. Using a metallic material for the first heat dissipation layer 121 can accelerate heat exchange, increasing the rate at which heat radiates into the space where the flexible circuit board is located, thereby reducing the surface and internal temperature of the flexible circuit board and ensuring its stability. Using a metallic material for the second heat dissipation layer 122 can also accelerate heat exchange, increasing the rate at which heat radiates into the space where the device to be bonded 200 is located, thereby reducing the surface and internal temperature of the device to be bonded 200 and ensuring its lifespan. Aerogels and ceramics have low thermal conductivity. Using at least one of aerogel and ceramic as the material for the heat-insulating layer 123 can further prevent the heat generated by the device to be bonded 200 and the flexible circuit board components 50 from being conducted to each other, thereby improving the stability of the flexible circuit board structure and the lifespan of the device to be bonded 200. The materials of the first heat dissipation layer 121 and the second heat dissipation layer 122 can also be other materials with high heat dissipation coefficients; the material of the heat-insulating layer 123 can also be other materials with low thermal conductivity.

[0070] In one embodiment of the present invention, optionally, the first heat dissipation layer 121 and / or the second heat dissipation layer 122 include a flexible carbon nanotube adhesive sheet. Carbon nanotubes are nanomaterials made of carbon atoms, with a thermal conductivity approximately 10 times that of copper, making them a promising heat dissipation material. However, the fragility of carbon nanotubes makes them difficult to process. This embodiment of the present invention is based on vertically aligned carbon nanotube lamination technology, where carbon nanotubes are laminated. During lamination, a carbon nanotube layer is placed between two laminates to form a laminated structure. The two laminates on either side protect the top and bottom of the carbon nanotubes, respectively. Protecting the carbon nanotubes through lamination stabilizes their shape and makes cutting and processing easier. Each laminate consists of a protective sheet and an adhesive layer. The adhesive layer is made of a polymer a few micrometers thick, but even a small amount of resin can generate significant thermal resistance; therefore, to achieve both adhesion and thermal conductivity, the polymer usage must be addressed. By optimizing three or more relevant parameters, such as the density of carbon nanotubes, the type and thickness of resin, and bonding conditions, sufficient adhesion can be maintained without compromising thermal conductivity while preserving the bonding of carbon nanotubes. Flexible carbon nanotube adhesive sheets possess excellent heat dissipation performance and good flexibility, thereby improving the overall flexibility of the device.

[0071] Figure 8This is a cross-sectional structural diagram of another flexible circuit board with heat insulation function provided in an embodiment of the present invention. Referring to 8, as an embodiment of the present invention, optionally, along the direction from the device to be bound 200 to the circuit layer 20, the thermal conductivity of the heat dissipation part gradually decreases to a first preset value and then gradually increases to a second preset value; wherein the first preset value is less than the second preset value.

[0072] Specifically, the heat dissipation section 12 can be understood as an integral film structure. That is, the heat-insulating layer 123 and the heat dissipation layer are an integral film structure. Along the direction from the device to be bonded 200 to the circuit layer 20, the thermal conductivity of the heat dissipation section 12 gradually decreases and then gradually increases. The heat dissipation section 12 near the device to be bonded 200 has a higher thermal conductivity, which can ensure the heat absorption efficiency of the heat dissipation section 12 on the device to be bonded 200, thereby dissipating and cooling the device to be bonded 200. The heat dissipation section 12 near the circuit layer 20 also has a higher thermal conductivity, which can ensure the heat absorption efficiency of the heat dissipation section 12 on the circuit layer 20 and the flexible circuit board components 50, thereby dissipating and cooling the flexible circuit board. The heat dissipation section 12 at the middle thickness position has a lower thermal conductivity, which can prevent the heat generated by the device to be bonded and the flexible circuit board components 50 from being conducted to each other, thereby improving the stability of the flexible circuit board structure and the service life of the device to be bonded. In one embodiment of the present invention, optionally, the thermal conductivity is closely related to the density. By configuring the density of the heat dissipation portion 12 to gradually decrease and then gradually increase along the direction from the device to be bonded 200 to the circuit layer 20, the thermal conductivity of the heat dissipation portion 12 can gradually decrease and then gradually increase. In another embodiment of the present invention, optionally, the material used for the heat dissipation portion 12 includes aluminum nitride (AlN). Aluminum oxide is a covalent compound, an insulator, an atomic crystal, belonging to diamond-like oxides. The thermal conductivity of the polymeric material of this type of diamond emulsion is 70-210 W / mK. Therefore, aluminum nitride has better heat transfer capabilities. In this embodiment, both the heat-insulating layer 123 and the heat dissipation layer are made of aluminum nitride, and at least one trace element in a predetermined proportion is doped into the heat-insulating layer 123 and / or the heat dissipation layers on both sides, so that the thermal conductivity of the heat-insulating layer 123 is less than that of the heat dissipation layers on both sides. Furthermore, by adjusting the doping ratio of trace elements, the thermal conductivity of the heat dissipation part 12 gradually decreases and then gradually increases along the direction from the device to be bonded 200 to the circuit layer 20.

[0073] Optionally, along the direction from the device to be bonded 200 to the circuit layer 20, the thermal conductivity of the first heat dissipation layer 121 gradually increases, and the thermal conductivity of the second heat dissipation layer 122 gradually decreases.

[0074] refer to Figure 1The present invention also provides a light-emitting module, including a light-emitting panel 210 and a circuit board with heat dissipation function as described in any of the above embodiments. The circuit board is disposed on the non-light-emitting side of the light-emitting panel 210, and the pads 30 on the circuit board are bonded to the bonding area 201 of the light-emitting panel 210.

[0075] By setting the flexible circuit board substrate layer 10 as a combination of flexible substrate and heat dissipation structure, heat dissipation can be achieved for the flexible circuit board components 50 and the light-emitting panel 210, and it also has the function of supporting the components. The heat dissipation structure combined with flexible films such as PI does not affect the bending performance of the flexible circuit board. The heat dissipation structure comprises three parts: a first heat dissipation layer 121, a second heat dissipation layer 122, and a heat-insulating layer 123 located between the first and second heat dissipation layers 121 and 122. The first heat dissipation layer 121 is disposed on the same layer as the bending portion 11, and the second heat dissipation layer 122 is located between the heat-insulating layer 123 and the light-emitting panel 210 and is in contact with the light-emitting panel 210. The first and second heat dissipation layers 121 and 122 have high heat dissipation coefficients, which can effectively dissipate heat from the flexible circuit board components 50 and the light-emitting panel 210, respectively. The heat-insulating layer 123 has a low thermal conductivity, which can prevent the heat generated by the light-emitting panel 210 from being transferred to the flexible circuit board, and also prevent the heat generated by the flexible circuit board components 50 from being transferred to the light-emitting panel 210. By controlling the heat between the heat-insulating layer 123 and the heat dissipation layers (121 / 122), the heat is conducted to the environment, reducing the heat conducted to the flexible circuit board, thereby improving the stability of the flexible circuit board structure; and reducing the heat conducted to the light-emitting panel 210, thereby improving the service life of the light-emitting panel 210.

[0076] Optionally, the light-emitting module also includes

[0077] The first graphene film is located on the side of the light-emitting panel 210 close to the circuit board.

[0078] The second graphene film is located on the side of the flexible circuit board component 50 away from the circuit layer 20.

[0079] Specifically, graphene is a two-dimensional crystal with advantages such as extremely high electrical and thermal conductivity, transparency, and chemical stability. A first graphene film is applied to the side of the light-emitting panel 210 closest to the flexible circuit board. The thermal conductivity of graphene further enhances heat dissipation for the light-emitting panel 210. Furthermore, a second graphene film can be attached to the side of the flexible circuit board component 50 furthest from the circuit layer. The thermal conductivity of graphene further enhances heat dissipation for the flexible circuit board component 50.

[0080] Note that the above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of the present invention, the scope of which is determined by the scope of the appended claims.

Claims

1. A flexible circuit board with heat dissipation function, characterized in that, include: The substrate layer includes a heat dissipation portion and a bending portion, wherein the heat dissipation portion is adjacent to the bending portion; A circuit layer located on the side of the substrate layer and / or inside the substrate layer; Pads and flexible circuit board components, wherein the vertical projection of the pads in the substrate layer is located in the bend; The pads are connected to the flexible circuit board components via the circuit layer; The heat dissipation part includes: a first heat dissipation layer, a second heat dissipation layer, and a heat-insulating layer located between the first heat dissipation layer and the second heat dissipation layer; the heat dissipation part is used to prevent the heat generated by the device to be bonded and the flexible circuit board components from being conducted to each other, and to dissipate the heat generated by the device to be bonded and the flexible circuit board components; the thickness of the heat dissipation part is greater than the thickness of the bending part, and the thickness of the first heat dissipation layer is greater than or equal to the thickness of the bending part.

2. The flexible circuit board with heat dissipation function according to claim 1, characterized in that, The first heat dissipation layer and / or the second heat dissipation layer include multiple hollow structures, which are used to increase the heat dissipation area of ​​the heat dissipation layer; The hollowed-out pattern of the hollowed-out structure includes at least one of polygons, circles, and ellipses.

3. The flexible circuit board with heat dissipation function according to claim 2, characterized in that, The first heat dissipation layer includes a first heat dissipation substrate in contact with the surface of the circuit layer, and a plurality of first heat dissipation fins fixed between the first heat dissipation substrate and the heat insulation layer. The cavity formed between two adjacent first heat dissipation fins serves as the hollow structure. The second heat dissipation layer includes a second heat dissipation substrate in contact with the surface of the device to be bonded, and a plurality of second heat dissipation fins fixed between the second heat dissipation substrate and the heat insulation layer. The cavity formed between two adjacent second heat dissipation fins serves as the hollow structure.

4. The flexible circuit board with heat dissipation function according to claim 3, characterized in that, The plane on which the first heat sink is located is perpendicular to the plane on which the first heat sink substrate is located; the planes on which each first heat sink is located are parallel to each other; and multiple first heat sinks are arranged at intervals in sequence. And / or, the plane on which the second heat sink is located is perpendicular to the plane on which the second heat sink substrate is located; the planes on which each second heat sink is located are parallel to each other; and a plurality of second heat sinks are arranged at intervals in sequence.

5. The flexible circuit board with heat dissipation function according to claim 3, characterized in that, The plane containing the first heat sink intersects with the plane containing the first heat sink substrate; the planes containing two adjacent first heat sinks intersect each other; multiple first heat sinks are arranged in a crisscross pattern to form multiple heat dissipation support frames; And / or, the plane on which the second heat sink is located intersects the plane on which the second heat sink substrate is located; The planes containing two adjacent second heat sinks intersect each other; Multiple second heat sinks are arranged in a crisscross pattern to form multiple heat dissipation support frames.

6. The flexible circuit board with heat dissipation function according to any one of claims 1 to 5, characterized in that, The material of the first heat dissipation layer includes metal; the material of the second heat dissipation layer includes metal; The material of the heat-insulating layer includes at least one of aerogel and ceramic.

7. The flexible circuit board with heat dissipation function according to claim 1, characterized in that, The first heat dissipation layer and / or the second heat dissipation layer include a flexible carbon nanotube adhesive sheet.

8. The flexible circuit board with heat dissipation function according to claim 1, characterized in that, Along the direction from the device to be bonded to the circuit layer, the thermal conductivity of the heat dissipation part gradually decreases to a first preset value and then gradually increases to a second preset value; wherein the first preset value is less than the second preset value.

9. A light-emitting module, characterized in that, It includes a light-emitting panel and a flexible circuit board with heat dissipation function as described in any one of claims 1 to 8, wherein the flexible circuit board is disposed on the non-light-emitting side of the light-emitting panel, and the pads on the flexible circuit board are bonded to the bonding area of ​​the light-emitting panel.

10. The light-emitting module according to claim 9, characterized in that, Also includes: A first graphene film is located on the side of the light-emitting panel closest to the flexible circuit board. The second graphene film is located on the side of the flexible circuit board component away from the circuit layer.

Images