Coated graphene heat-conducting gasket and electronic equipment

Abstract

The embodiment of the utility model provides a coated graphene heat-conducting gasket and electronic equipment, and relates to the technical field of graphene application. The coated graphene heat-conducting gasket comprises a graphene sheet and a polyimide coating layer coating all the surfaces of the graphene sheet, and the polyimide coating layer comprises a first polyimide film covering the bottom surface, the side edge and the edge part of the top surface of the graphene sheet. And the second polyimide film covers the middle part of the top surface of the graphene sheet and the first polyimide film above the graphene sheet. The coated graphene heat-conducting gasket and the electronic equipment provided by the embodiment of the utility model not only have heat-conducting property, but also have excellent insulating property, so that the risk of short circuit caused by graphene can be avoided.

Description

Technical Field

[0001] This application relates to the field of graphene application technology, and more specifically, to a coated graphene thermal conductive pad and electronic device. Background Technology

[0002] Graphene is a material composed of carbon atoms arranged in sp... 2 The single-layer two-dimensional honeycomb lattice structure material formed by hybrid orbitals can have a thermal conductivity as high as 5300 W / (m·K), far exceeding that of traditional thermally conductive materials (such as copper and aluminum). Based on this, graphene has broad application prospects in fields such as heat dissipation in electronic devices. For example, placing graphene-made thermal pads between heat-generating devices and heat sinks can effectively improve heat conduction efficiency, reduce the operating temperature of heat-generating devices, and thus extend their service life.

[0003] However, while existing technologies utilize graphene's excellent thermal conductivity, they also face some challenges. Specifically, although graphene exhibits excellent thermal conductivity, its electrical conductivity is also remarkable, which limits its application in certain insulation scenarios. For example, in electronic devices requiring insulation, the presence of graphene may cause short circuits. Utility Model Content

[0004] The purpose of this application is to provide a coated graphene thermally conductive pad and an electronic device, which not only has thermal conductivity but also excellent insulation properties, thereby avoiding the short circuit risk caused by graphene.

[0005] In a first aspect, embodiments of this application provide a coated graphene thermal pad, which includes a graphene sheet and a polyimide coating layer covering all surfaces of the graphene sheet. The polyimide coating layer includes a first polyimide film covering the bottom, side, and top edge portions of the graphene sheet, and a second polyimide film covering the middle portion of the top surface of the graphene sheet and above the first polyimide film.

[0006] In the above implementation process, this technical solution uses a very thin single-sided PI film to cover the graphene gasket, which improves its insulation performance and avoids the risk of short circuit.

[0007] This technical solution further enhances the strength of graphene thermal pads, preventing cracking during long-term use.

[0008] This technical solution combines the high thermal conductivity and high resilience of graphene thermal pads with the high insulation properties of PI film, thus meeting the application requirements of high thermal conductivity, high insulation, and high resilience.

[0009] In one possible implementation, the thickness of the first polyimide film is 3-40 μm; the thickness of the second polyimide film is 3-40 μm.

[0010] In the above implementation process, the graphene thermal pad can be completely wrapped by a PI film, which makes it more adaptable to different application scenarios. Different thicknesses of PI film can be selected to wrap the graphene thermal pad according to actual needs to meet different application requirements. The thicker the PI film, the better the insulation and the higher the strength. A relatively thin PI film was selected to reduce heat loss.

[0011] In one possible implementation, the thickness of the first polyimide film is 3-10 μm; the thickness of the second polyimide film is 3-10 μm.

[0012] In the above implementation process, a very thin PI film was selected to reduce thermal performance loss.

[0013] In one possible implementation, a first adhesive layer is disposed on the surface of the first polyimide film adjacent to the surface of the graphene sheet, and a second adhesive layer is disposed on the surface of the second polyimide film adjacent to the surface of the graphene sheet.

[0014] In the above implementation process, single-sided PI film refers to a single-sided adhesive PI film. The reason for choosing PI film is that it has good insulation, high temperature resistance, and can form a good bond with graphene gaskets.

[0015] In one possible implementation, the thermal conductivity of the first polyimide film is >0.4 W / (m·K), and the thermal conductivity of the second polyimide film is >0.4 W / (m·K).

[0016] In the above implementation process, the selected PI film has a higher thermal conductivity than the conventional PI film on the market, generally exceeding 0.4 W / m K.

[0017] In one possible implementation, the edge of the first polyimide film has a notch or cut line, and the number of overlapping layers of the first polyimide film covering the top surface of the graphene sheet is ≤2.

[0018] In one possible implementation, the thickness of the polyimide coating layer covering the bottom and side surfaces of the graphene sheet is 3-10 μm, and the thickness of the polyimide coating layer covering the top surface of the graphene sheet is 3-30 μm.

[0019] In one possible implementation, the width of the first polyimide film covering the top edge portion of the graphene sheet is 0.1-0.5 mm.

[0020] In one possible implementation, the thickness of the graphene sheet is 0.1-5 mm;

[0021] And / or, the graphene sheet comprises multiple layers of graphene films stacked sequentially, with an adhesive disposed between adjacent layers of the graphene films, and through holes extending through the graphene films along the stacking direction, with carbon fiber filaments fixed inside the through holes.

[0022] Secondly, embodiments of this application provide an electronic device that includes the coated graphene thermal pad provided in the first aspect. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 An exploded structural diagram of a coated graphene thermal pad provided in an embodiment of this application;

[0025] Figure 2 This is a schematic diagram of the structure after step S1 is completed in the preparation method of the coated graphene thermal pad provided in the embodiments of this application;

[0026] Figure 3 This is a schematic diagram of the structure after step S2 in the preparation method of the coated graphene thermal pad provided in the embodiments of this application;

[0027] Figure 4 This is a schematic diagram of the structure after step S3 is completed in the preparation method of the coated graphene thermal pad provided in the embodiments of this application.

[0028] Icons: 110 - First polyimide film; 120 - Graphene sheet; 130 - Second polyimide film. Detailed Implementation

[0029] The technical solutions in the embodiments of this application will now be described with reference to the accompanying drawings.

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] In the description of this application, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In addition, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0034] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0035] Please refer to Figure 1 This embodiment provides a coated graphene thermal pad, which includes a graphene sheet 120 and a polyimide coating layer covering all surfaces of the graphene sheet 120. The polyimide coating layer includes a first polyimide film 110 covering the bottom, side and top edge portions of the graphene sheet 120, and a second polyimide film 130 covering the middle of the top surface of the graphene sheet 120 and above the first polyimide film 110.

[0036] In one possible implementation, the thickness of the first polyimide film 110 is 3-40 μm; the thickness of the second polyimide film 130 is 3-40 μm. Optionally, the thickness of the first polyimide film 110 is 3-10 μm; the thickness of the second polyimide film 130 is 3-10 μm.

[0037] In one possible implementation, a first adhesive layer is disposed on the surface of a first polyimide film 110 adjacent to the surface of a graphene sheet 120, and a second adhesive layer is disposed on the surface of a second polyimide film 130 adjacent to the surface of a graphene sheet 120. The thermal conductivity of the first polyimide film 110 is >0.4 W / (m·K), and the thermal conductivity of the second polyimide film 130 is >0.4 W / (m·K).

[0038] In one possible implementation, the edge of the first polyimide film 110 has a notch or a cut line, and the number of overlapping layers of the first polyimide film 110 covering the top surface of the graphene sheet 120 is ≤2 layers. Specifically, the thickness of the polyimide coating layer covering the bottom and side surfaces of the graphene sheet 120 is 3-10 μm, and the thickness of the polyimide coating layer covering the top surface of the graphene sheet 120 is 3-30 μm.

[0039] In one possible implementation, the width of the first polyimide film 110 covering the top edge portion of the graphene sheet 120 is 0.1-0.5 mm, optionally 0.2-0.3 mm.

[0040] In one possible implementation, the graphene sheet 120 has a thickness of 0.1-5 mm, optionally 0.3-2 mm; the graphene sheet 120 comprises multiple layers of sequentially stacked graphene films, with an adhesive disposed between adjacent graphene films, and through-holes extending along the stacking direction on the graphene films, with carbon fiber filaments fixed within the through-holes. Exemplarily, the graphene sheet 120 is the graphene sheet 120 disclosed in patent number CN202122213698.3.

[0041] This application provides a method for preparing a coated graphene thermal pad, which includes the following steps:

[0042] S1. Graphene sheet 120 is laminated and stacked on the first polyimide film 110, with graphene sheet 120 located in the middle of the first polyimide film 110. For the specific structure, please refer to [link / reference needed]. Figure 2 .

[0043] S2. Using a bending process, the edge of the first polyimide film 110 exposed on the graphene sheet 120 is bent upwards until it adheres to and covers the side and top edges of the graphene sheet 120. For the specific structure, please refer to [link / reference needed]. Figure 3 .

[0044] In one possible implementation, before step S1, the first polyimide film 110 is cut so that the area of ​​the first polyimide film 110 is larger than the bottom area of ​​the graphene sheet 120, and the bent first polyimide film 110 can cover the top edge of the graphene sheet 120.

[0045] In one possible implementation, before step S1, the first polyimide film 110 is cut to have a notch or cut line at the edge, so that the number of overlapping layers of the portion of the bent first polyimide film 110 covering the top surface of the graphene sheet 120 is ≤2 layers.

[0046] S3. The second polyimide film 130 is laminated and covered onto the top center of the graphene sheet 120 and the first polyimide film 110 above it to form a fully encapsulated structure. Please refer to the specific structure. Figure 4 .

[0047] In one possible implementation, before step S3, the second polyimide film 130 is cut so that the area of ​​the second polyimide film 130 is larger than the area in the middle of the top surface of the graphene sheet 120 that is not covered by the first polyimide film 110.

[0048] S4. Roll the fully enclosed structure.

[0049] In addition, this application provides an electronic device that includes the coated graphene thermal pad provided in the foregoing embodiments.

[0050] The features and performance of this application will be further described in detail below with reference to the embodiments.

[0051] Example 1

[0052] This embodiment provides a coated graphene thermal pad, which includes a graphene sheet and a polyimide coating layer covering all surfaces of the graphene sheet. The polyimide coating layer includes a first polyimide film covering the bottom, side and top edge portions of the graphene sheet, and a second polyimide film covering the middle of the top surface of the graphene sheet and above the first polyimide film.

[0053] The graphene sheet used is the graphene sheet disclosed in patent number CN202122213698.3, and its thickness is 0.3 mm. The thickness of the first polyimide film is 5 μm; the thickness of the second polyimide film is 5 μm.

[0054] The first polyimide film has a notch at its edge. The first polyimide film has two overlapping layers covering the top surface of the graphene sheet. Specifically, the thickness of the polyimide coating layer covering the bottom and sides of the graphene sheet is 5 μm, and the thickness of the polyimide coating layer covering the top surface of the graphene sheet is 5 μm, 10 μm, and 15 μm, respectively. The width of the first polyimide film covering the edge of the top surface of the graphene sheet is 0.2 mm.

[0055] Example 2

[0056] This embodiment provides a coated graphene thermal pad, which differs from Embodiment 1 in that the thickness of the graphene sheet is 1 mm.

[0057] Example 3

[0058] This embodiment provides a coated graphene thermal pad, which differs from Embodiment 1 in that the thickness of the graphene sheet is 2mm.

[0059] Example 4

[0060] This embodiment provides a coated graphene thermal pad, which differs from Embodiment 1 in that: the thickness of the first polyimide film is 50 μm; the thickness of the second polyimide film is 50 μm.

[0061] Example 5

[0062] This embodiment provides a coated graphene thermal pad, which differs from Embodiment 4 in that the thickness of the graphene sheet is 1 mm.

[0063] Example 6

[0064] This embodiment provides a coated graphene thermal pad, which differs from Embodiment 4 in that the thickness of the graphene sheet is 2mm.

[0065] Comparative Example 1

[0066] This comparative example provides a coated graphene thermal pad, which includes a graphene sheet and a polyimide coating layer covering all surfaces of the graphene sheet. The polyimide coating layer includes a single polyimide film covering the bottom, sides and top of the graphene sheet.

[0067] The graphene sheet used is the graphene sheet disclosed in patent number CN202122213698.3, and its thickness is 0.3 mm. The polyimide film has a thickness of 5 μm.

[0068] The polyimide film has a notch at its edge, and the width of the overlapping area of ​​the opposite edge of the polyimide film covering the top surface of the graphene sheet is 0.2 mm.

[0069] The performance parameters of the coated graphene thermal pads of Examples 1-5 and Comparative Example 1 were tested, and the results are shown in the table below.

[0070]

[0071] The results in the table above show that the thickness of the polyimide film used for coating affects the tensile strength and the coating graphene thermal pad. When the thickness of the polyimide film (first polyimide film and second polyimide film) is selected as 5μm, the coating graphene thermal pad has a lower thermal resistance, thus having better thermal conductivity, while also taking into account better insulation performance (breakdown voltage resistance) and strength (tensile strength). Moreover, using two polyimide films for coating can achieve better insulation performance and strength than using only one polyimide film.

[0072] In summary, the coated graphene thermal pad and electronic device of this application not only have thermal conductivity but also excellent insulation properties, thereby avoiding the short circuit risk caused by graphene.

[0073] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A coated graphene thermal pad, characterized in that, It includes a graphene sheet and a polyimide coating layer covering all surfaces of the graphene sheet. The polyimide coating layer includes a first polyimide film covering the bottom, side and top edge portions of the graphene sheet, and a second polyimide film covering the middle of the top surface of the graphene sheet and above the first polyimide film.

2. The coated graphene thermal pad according to claim 1, characterized in that, The thickness of the first polyimide film is 3-40 μm; the thickness of the second polyimide film is 3-40 μm.

3. The coated graphene thermal pad according to claim 2, characterized in that, The thickness of the first polyimide film is 3-10 μm; the thickness of the second polyimide film is 3-10 μm.

4. The coated graphene thermal pad according to any one of claims 1 to 3, characterized in that, The first polyimide film has a first adhesive layer disposed on the surface adjacent to the graphene sheet, and the second polyimide film has a second adhesive layer disposed on the surface adjacent to the graphene sheet.

5. The coated graphene thermal pad according to claim 1, characterized in that, The thermal conductivity of the first polyimide film is >0.4 W / (m·K), and the thermal conductivity of the second polyimide film is >0.4 W / (m·K).

6. The coated graphene thermal pad according to claim 2 or 3, characterized in that, The first polyimide film has a notch or cut line at its edge, and the number of overlapping layers of the first polyimide film covering the top surface of the graphene sheet is ≤2.

7. The coated graphene thermal pad according to claim 6, characterized in that, The thickness of the polyimide coating layer covering the bottom and side surfaces of the graphene sheet is 3-10 μm, and the thickness of the polyimide coating layer covering the top surface of the graphene sheet is 3-30 μm.

8. The coated graphene thermal pad according to claim 1, characterized in that, The width of the first polyimide film covering the top edge of the graphene sheet is 0.1-0.5 mm.

9. The coated graphene thermal pad according to claim 1, characterized in that, The thickness of the graphene sheet is 0.1-5 mm; And / or, the graphene sheet comprises multiple layers of graphene films stacked sequentially, with an adhesive disposed between adjacent layers of the graphene films, and through holes extending through the graphene films along the stacking direction, with carbon fiber filaments fixed inside the through holes.

10. An electronic device, characterized in that, It includes the coated graphene thermal pad as described in any one of claims 1 to 9.

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