Heat dissipation film, preparation method thereof and display device

Abstract

The invention provides a heat dissipation film and a preparation method thereof and a display device, the heat dissipation film comprises a composite adhesive layer and a metal layer which are stacked, and the composite adhesive layer comprises an adhesive layer main body and a metal net; the material of the adhesive layer main body has bonding and stress buffering performance, the metal net is embedded between a first surface and a second surface of the adhesive layer main body and is configured to limit adhesive flowing of the adhesive layer main body in the direction parallel to the metal layer, the first surface is a surface close to the metal layer, and the second surface is a surface far away from the metal layer.

Description

Technical Field

[0001] The present disclosure relates to the field of display technology, and in particular to a heat dissipation film and a preparation method thereof, and a display device. Background Art

[0002] With the development of display technology, thinness has become one of the important directions for the development of display devices. Especially for portable display devices such as mobile phones and tablet computers, people tend to choose lighter and thinner products. Therefore, it is necessary to thin the film layers in the display device, such as the heat dissipation film. Summary of the invention

[0003] In a first aspect, an embodiment of the present disclosure provides a heat dissipation film, comprising: a composite adhesive layer and a metal layer stacked together, wherein the composite adhesive layer comprises: an adhesive layer body and a metal mesh;

[0004] The material of the adhesive layer body has bonding and stress buffering properties, the metal mesh is embedded between the first surface and the second surface of the adhesive layer body, and is configured to limit the flow of adhesive in the adhesive layer body in a direction parallel to the metal layer, wherein the first surface is a surface close to the metal layer, and the second surface is a surface away from the metal layer.

[0005] Optionally, the metal mesh is arranged parallel to the metal layer, and along a direction perpendicular to the metal layer, the distance between the metal mesh and the first surface of the adhesive layer body is a first distance, and the distance between the metal mesh and the second surface of the adhesive layer body is a second distance, and the first distance is equal to the second distance.

[0006] Optionally, the composite adhesive layer includes: a first adhesive layer, a metal mesh, and a second adhesive layer stacked in sequence, and the first adhesive layer and the second adhesive layer constitute the adhesive layer body.

[0007] Optionally, the orthographic projection of the metal mesh on the metal layer covers the entire metal layer, or the orthographic projection of the metal mesh on the metal layer covers an edge region of the metal layer.

[0008] Optionally, along a direction perpendicular to the metal layer, an edge of the metal mesh is aligned with an edge of the metal layer.

[0009] Optionally, the material of the adhesive layer body includes silicone.

[0010] Optionally, the grid of the metal mesh is a diamond grid, and the angle between two relative acute angles in the diamond grid is greater than or equal to 80 degrees and less than 90 degrees.

[0011] Optionally, the heat dissipation film further includes a protective film, and the protective film is attached to a side of the adhesive layer body away from the metal layer.

[0012] In a second aspect, an embodiment of the present disclosure provides a display device, comprising: a display panel and the heat dissipation film provided in the first aspect, wherein the heat dissipation film is attached to the backlight side of the display panel via a composite adhesive layer.

[0013] Optionally, along the direction toward the backlight side of the display panel, the distance between the side surface of the composite adhesive layer and the side surface of the metal layer on the same side shows a trend of first increasing, then decreasing, and then increasing.

[0014] In a third aspect, an embodiment of the present disclosure provides a method for preparing a heat dissipation film, which is used to prepare the heat dissipation film provided in the first aspect above, and the method includes: forming a first adhesive layer on a protective film; forming a metal mesh on the first adhesive layer; forming a second adhesive layer on the metal mesh; and attaching a metal layer on the second adhesive layer.

[0015] Optionally, after attaching the metal layer on the second adhesive layer, the method further includes:

[0016] The stacked structure composed of the metal layer, the second adhesive layer, the metal mesh, the first adhesive layer and the protective film is cut according to a predetermined cutting line to obtain a heat dissipation film, wherein the metal mesh covers the cutting line.

[0017] The technical solution provided in the embodiments of the present disclosure has at least the following technical effects or advantages:

[0018] The heat dissipation film, preparation method thereof, and display device provided in the embodiments of the present disclosure adopt a composite adhesive layer to replace the grid adhesive superimposed foam structure of the traditional heat dissipation film. A metal mesh is embedded in the adhesive layer body of the composite adhesive layer. The metal mesh is configured to limit the lateral adhesive flow in the adhesive layer body. This can avoid the thickness limitation caused by the foam and achieve thinning of the heat dissipation film, which is beneficial to reducing the thickness of the display device. On the other hand, it can improve the problem of adhesive overflow caused by using the adhesive layer as a buffer.

[0019] The above description is only an overview of the technical solution provided by the embodiment of the present disclosure. In order to more clearly understand the technical means of the embodiment of the present disclosure, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present disclosure more obvious and easy to understand, the specific implementation method of the embodiment of the present disclosure is listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0021] Figure 1 is a schematic top view of a display device in an embodiment of the present disclosure;

[0022] Figure 2 for Figure 1 AA cross-section diagram of ;

[0023] Figure 3 is a schematic diagram of an exemplary single-layer metal mesh in an embodiment of the present disclosure;

[0024] Figure 4 Shows Figure 3 Schematic diagram of a single grid in ;

[0025] Figure 5 is a schematic diagram of another exemplary single-layer metal mesh in an embodiment of the present disclosure;

[0026] Figure 6 A schematic diagram of a display device provided for a comparative example;

[0027] Figure 7 is a flow chart of a method for preparing a heat dissipation film in an embodiment of the present disclosure;

[0028] Figure 8 This is a schematic diagram of preparing a composite adhesive layer in an embodiment of the present disclosure;

[0029] Fig. 9 Schematic diagram of the heat dissipation film obtained after cutting in the embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that the term "plurality" appearing herein includes two or more than two situations.

[0031] As used herein, "about," "substantially," or "approximately" includes the stated value and an average value that is within an acceptable range of variation from the particular value as determined by one of ordinary skill in the art taking into account the measurements in question and the errors associated with the measurement of the particular quantity (i.e., the limitations of the measurement system).

[0032] As used herein, "parallel", "perpendicular", and "equal" include the situations described and situations similar to the situations described, and the range of the similar situations is within the acceptable deviation range, wherein the acceptable deviation range is determined by a person of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, "parallel" includes absolute parallelism and approximate parallelism, wherein the acceptable deviation range of approximate parallelism may be, for example, a deviation within 5°; "perpendicular" includes absolute perpendicularity and approximate perpendicularity, wherein the acceptable deviation range of approximate perpendicularity may also be, for example, a deviation within 5°. "Equal" includes absolute equality and approximate equality, wherein the acceptable deviation range of approximate equality may be, for example, the difference between the two equalities is less than or equal to 5% of either one.

[0033] It will be understood that when a layer or an element is referred to as being on another layer or substrate, it can be directly on the other layer or substrate, or intervening layers may be present between the layer or element and the other layer or substrate.

[0034] In order to achieve the thinness and lightness of the display device, it is necessary to design the thinning of the film layer in the display device while meeting the performance requirements. At present, the heat dissipation film of the display device usually adopts a super clean foam (SCF) composite film, that is, a stacked structure of a grid adhesive layer, foam and metal. Limited by the thickness of the foam, the overall film thickness can reach 0.2mm and above. In some examples, an adhesive layer such as silicone is used to replace the grid adhesive layer and foam to thin the heat dissipation film. For example, it can be thinned to 0.16mm, thereby reducing the thickness of the display device. Silicone has buffering, exhaust and bonding properties, and can achieve the performance of a grid adhesive layer superimposed with foam.

[0035] However, in the actual use of silicone heat dissipation film, it was found that due to the thicker adhesive layer, which is much thicker than the grid adhesive thickness in SCF, there is a serious problem of adhesive overflow during the preparation and use of the heat dissipation film. In addition, since the silicone heat dissipation film is relatively soft, there may be deformation of the cutting edge during the preparation process, resulting in a low yield rate of the finished heat dissipation film.

[0036] Based on this, the embodiment of the present disclosure adopts a composite adhesive layer to replace the traditional grid adhesive superimposed foam structure. A metal mesh is embedded in the adhesive layer body of the composite adhesive layer, and the metal mesh is configured to limit the lateral adhesive flow in the adhesive layer body. This can avoid the thickness limitation brought by the foam and achieve thinning of the heat dissipation film, which is beneficial to reducing the thickness of the display device. On the other hand, it can improve the problem of adhesive overflow caused by using the adhesive layer as a buffer.

[0037] The display device provided by the embodiment of the present disclosure is described in detail below with reference to the accompanying drawings. For example, the display device can be any product or component with a display function, such as a display screen, a mobile phone, a laptop computer, a tablet computer, a television, a digital photo frame, etc., and this embodiment does not limit this.

[0038] Figure 1 A schematic plan view of an exemplary display device according to an embodiment of the present disclosure is shown; Figure 2 Shows Figure 1 AA cross-sectional view of the display device is shown in FIG. Figure 1 and Figure 2 As shown, the display device 10 includes: a display panel 11 and a heat dissipation film 12 arranged on the backlight side of the display panel 11 .

[0039] The display panel 11 includes a display area AA and a non-display area SA at least arranged on one side of the display area AA. The display area AA includes a plurality of pixels arranged in an array, each pixel includes a plurality of sub-pixels, and each sub-pixel can display a single color, such as a red sub-pixel displays red, a green sub-pixel displays green, and a blue sub-pixel displays blue. The brightness (grayscale) of the sub-pixels of different colors in each pixel can be adjusted, and the display of multiple colors can be achieved through color combination and superposition, thereby realizing full-color display of the display panel 11.

[0040] In some examples, the plurality of sub-pixels include a first sub-pixel, a second sub-pixel, and a third sub-pixel, and different sub-pixels emit different colors. For example, the first sub-pixel may be a red sub-pixel, the second sub-pixel may be a green sub-pixel, and the third sub-pixel may be a blue sub-pixel. The specific configuration may be based on actual application scenarios, and this embodiment does not limit this.

[0041] The display panel 11 can be a liquid crystal display panel, a micro light emitting diode (Micro Light Emitting Diode, MLED) display panel, an organic light emitting diode (Organic Light Emitting Diode, OLED) display panel or a quantum dot organic light emitting diode (Quantum Dot Light Emitting Diodes, QLED), etc., and can be set according to the needs of the actual application scenario, and this embodiment does not impose any restrictions on this.

[0042] In some examples, the display panel 11 may include: a backplane 111, a display layer 112, and a protective layer 113 stacked in sequence. The side of the backplane 111 away from the display layer 112 is the backlight side of the display panel 11, and the side of the cover plate away from the display layer 112 is the light emitting side of the display panel 11.

[0043] For example, the backplane 111 may include: a substrate and a pixel driving circuit layer disposed on the substrate. Of course, the backplane 111 may also include other structures, which are specifically designed according to the needs of the actual product. For example, in some examples, the backplane 111 may also include a fingerprint recognition circuit, etc., which is not limited in this embodiment.

[0044] For example, the substrate may be a rigid substrate, which may include a glass substrate, a PMMA (Polymethyl methacrylate) substrate, a silicon substrate, etc. In this case, the display panel 11 may be a rigid display panel.

[0045] For another example, the substrate may be a rigid substrate. It may be a flexible substrate. The flexible substrate may include, for example, a PET (Polyethylene Terephthalate) substrate, a PEN (Polyethylenenaphthalate di formic acid glycol ester) substrate, or a PI (Polyimide) substrate. In this case, the display panel 11 may be a flexible display panel.

[0046] It should be noted that the substrate may be a one-layer structure or a multi-layer structure. For example, the substrate may include at least one flexible substrate and at least one buffer layer, and the flexible substrate and the buffer layer are alternately stacked.

[0047] The pixel driving circuit layer is used to form a plurality of pixel driving circuits distributed in an array. The pixel driving circuit may include a plurality of electronic components such as transistors and capacitors. For example, each pixel driving circuit may include three transistors and one capacitor, forming a 3T1C (i.e., a driving transistor, two switching transistors and one capacitor). It may also include more than three transistors and at least one capacitor, such as a 4T1C (i.e., a driving transistor, three switching transistors and one capacitor), a 5T1C (i.e., a driving transistor, four switching transistors and one capacitor) or a 7T1C (i.e., a driving transistor, six switching transistors and one capacitor), etc. Among them, the transistor may be a thin film transistor (Thin Film Transistor, referred to as TFT), a field effect transistor (metal oxide semiconductor, referred to as MOS) or other switching devices with the same characteristics.

[0048] It can be understood that the transistor may include a control electrode, a first electrode, and a second electrode. The control electrode is the gate of the transistor, the first electrode is one of the source and drain of the transistor, and the second electrode is the other of the source and drain of the transistor. Since the source and drain of the transistor may be symmetrical in structure, the source and drain may be structurally indistinguishable, so the source of the transistor is called the first electrode, and may also be called the second electrode.

[0049] For example, the pixel driving circuit layer may include an active layer, a first gate metal layer (Gate1), a second gate metal layer (Gate2), a first metal wiring layer (SD1) and a second metal wiring layer (SD2), and these functional layers are configured to form transistors, capacitors and multiple signal lines for pixel driving in the pixel driving circuit. For example, the multiple signal lines may include: power signal lines, data signal lines, reset signal lines, scan signal lines, enable signal lines and initialization signal lines, etc. For details, please refer to the relevant technology, which will not be described in detail here. The pixel driving circuit layer may also include an insulating layer that separates these functional layers. It should be noted that the functional layers of the pixel driving circuit layer listed above are only for illustration. In other examples, the pixel driving circuit layer may also include more or fewer functional layers, for example, more metal wiring layers, which are specifically set according to the needs of the actual product, and this embodiment does not limit this.

[0050] In some examples, the display layer 112 may include: a light emitting device layer, an encapsulation layer, and a color filter layer. The light emitting device layer is stacked on a side of the pixel driving circuit layer away from the substrate. The light emitting device layer may include: a pixel defining layer and a plurality of light emitting devices. The pixel defining layer has a plurality of pixel openings, and one pixel opening defines the position of one light emitting device. For example, the light emitting device may be an MLED, an OLED, or a QLED.

[0051] Taking OLED as an example, in the direction away from the substrate, the light-emitting device may include a first electrode, a light-emitting layer, and a second electrode stacked in sequence. Of course, the light-emitting device may also include at least one of a hole injection layer, a hole transport layer, and an electron blocking layer disposed between the first electrode and the light-emitting layer, and at least one of an electron injection layer, an electron transport layer, and a hole blocking layer disposed between the second electrode and the light-emitting layer, which may be specifically arranged according to actual needs, and this embodiment does not limit this.

[0052] For example, the first electrode may be an anode, and the second electrode may be a cathode. The structure of the anode may be a composite structure composed of a transparent conductive oxide film / metal film / transparent conductive oxide film stacked in sequence. The material of the transparent conductive oxide film may be any one of ITO (Indium tin oxide) and IZO (Indium zinc oxide), and the material of the metal film may be any one of gold (Au), silver (Ag), nickel (Ni) and platinum (Pt). For another example, the structure of the anode may be a single-layer structure, and the material of the single-layer structure may be any one of ITO, IZO, Au, Ag, Ni, and Pt.

[0053] Each pixel opening exposes a portion of the anode of the corresponding light-emitting device, and at least a portion of the light-emitting layer is located in the corresponding pixel opening and is electrically connected to the corresponding anode.

[0054] For example, the cathodes of the light emitting devices may be electrically connected to each other to form an integrated structure. For example, the cathode material may be any one of aluminum (Al), silver (Ag) and magnesium (Mg), or any one of magnesium-silver alloy and aluminum-lithium alloy.

[0055] The encapsulation layer is arranged on the side of the light-emitting device layer away from the substrate to protect the light-emitting device. In some examples, the display panel 11 may include a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer. For example, the first inorganic encapsulation layer and the second inorganic encapsulation layer may be made of inorganic materials such as nitrides, oxides, nitrogen oxides, nitrates, carbides, or any combination thereof, and the preparation process may adopt a chemical vapor deposition (CVD) process, such as a plasma enhanced chemical vapor deposition (PECVD) process. For example, the organic insulating layer may be made of materials such as acrylic, hexamethyldisiloxane, polyacrylates, polycarbonates, polystyrene, and the preparation process may adopt an inkjet printing (IJP) process. Of course, in other examples, other encapsulation methods may also be used, such as inorganic thin film encapsulation, which is not limited in this embodiment.

[0056] In some examples, the color filter layer can be arranged on the side of the encapsulation layer away from the base substrate, and the color filter layer may include: a first color filter, a second color filter, and a third color filter. The first color filter, the second color filter, and the third color filter are color filters of different colors. The first color filter, the second color filter, and the third color filter may have different thicknesses, or the same thickness, or two of the thicknesses are the same and the other thickness is different, which is not limited in this embodiment. Of course, in other examples, the color filter layer may also be arranged on another opposing substrate, which is not limited in this embodiment.

[0057] In some examples, adjacent color filters of the color film layer do not overlap with each other, and the color film layer also includes a black matrix arranged between adjacent color filters to absorb ambient light, reduce ambient light reflection of the display panel 11, and realize that the screen is dark when it is turned off. Of course, in other examples, the first color filter and the second color filter may have a first overlapping area, the second color filter and the third color filter may have a second overlapping area, and the third color filter and the first color filter may have a third overlapping area. When two filters of different colors overlap, the light transmittance of the overlapping area is low, so it can be used as a black matrix, so that the first overlapping area, the second overlapping area, and the third overlapping area of ​​the display panel 11 can all be used as a black matrix to achieve a light shielding effect without the need to set up an additional black matrix.

[0058] For example, the first color filter is a red filter, the second color filter is a green filter, and the third color filter is a blue filter.

[0059] In some examples, the display panel 11 may further include a touch layer for realizing a touch function. For example, the touch layer may be disposed between the encapsulation layer and the color filter layer to realize an in-screen touch structure, which is beneficial for reducing the thickness of the display panel 11. Of course, in other examples, the touch layer may also be disposed at other positions of the display panel 11, and this embodiment does not limit this.

[0060] In some examples, the protective layer 113 may be a cover glass, which may be bonded to the display layer 112 by transparent optical adhesive. Of course, in other examples, the protective layer 113 may also be made of other materials such as transparent resin material, PET (Polyethylene terephthalate), ultra-thin glass (UTG) and colorless polyimide (CPI), etc., which is not limited in this embodiment.

[0061] The heat dissipation film 12 not only dissipates heat for the display panel 11, but also acts as a stress buffer. The specific structure of the heat dissipation film 12 provided in the embodiment of the present disclosure is described in detail below.

[0062] In the disclosed embodiment, the heat dissipation film 12 may include: a stacked metal layer 123 and a composite adhesive layer 120. The composite adhesive layer 120 includes: an adhesive layer body 121 and a metal mesh 122. For ease of explanation, the surface of the adhesive layer body 121 close to the metal layer 123 is referred to as the first surface, and the surface away from the metal layer 123 is referred to as the second surface, and the first surface and the second surface are opposite. The metal mesh 122 is embedded between the first surface and the second surface of the adhesive layer body 121, and is configured to limit the lateral adhesive flow in the adhesive layer body 121, especially the lateral adhesive flow when the adhesive layer body 121 is subjected to pressure in a direction perpendicular to the metal layer 123, so as to improve the anti-deformation ability of the composite adhesive layer 120, thereby reducing the amount of adhesive overflow during the preparation and use of the heat dissipation film 12. Among them, "lateral adhesive flow" refers to the adhesive flow of the adhesive layer body 121 in a direction parallel to the metal layer 123.

[0063] The metal layer 123 plays a role in heat dissipation. In some examples, the metal layer 123 can be attached to the first surface of the adhesive layer body 121. Of course, in other examples, the heat dissipation film 12 can also include other film layers, such as a graphene layer, which can also play an auxiliary heat dissipation role, and can be arranged between the metal layer 123 and the composite adhesive layer 120, or can also be arranged on the side of the metal layer 123 away from the composite adhesive layer 120, which is not limited in this embodiment.

[0064] When in use, the heat dissipation film 12 can be attached to the backlight side of the display panel 11 through its own composite adhesive layer 120 to achieve heat dissipation of the display panel 11. The composite adhesive layer 120 serves as both an adhesive layer and a stress buffer, so that the display device 10 has the ability to resist impact and extrusion. Of course, the unused heat dissipation film 12 can also include a protective film (also called a bottom protective film), which is attached to the side of the adhesive layer body 121 away from the metal layer 123 to protect the composite adhesive layer 120. When in use, the protective film needs to be peeled off first and then attached to the backlight side of the display panel 11.

[0065] The thickness of the adhesive layer body 121 and the thickness of the metal mesh 122 can be set according to the performance requirements and thickness reduction requirements of the composite adhesive layer 120. In the direction perpendicular to the metal layer 123, the thickness of the heat dissipation film 12 provided in the embodiment of the present disclosure is less than the thickness of the traditional SCF heat dissipation film 12 to meet the thickness reduction requirements.

[0066] The material of the adhesive layer body 121 has bonding and stress buffering properties. Considering that silicone has buffering, exhaust and bonding properties, in some examples, the material of the adhesive layer body 121 may include silicone. Of course, in other examples, other materials with similar properties to silicone may also be used, and this embodiment does not limit this.

[0067] Considering the cost problem, the material of the metal mesh 122 and the material of the metal layer 123 can be selected from copper and stainless steel (SUS). Of course, in other examples, other metal materials can also be used, which are specifically set according to the needs of the actual product, and this embodiment does not limit this.

[0068] In the embodiment of the present disclosure, a single layer of metal mesh 122 or multiple layers of metal mesh 122 may be embedded in the adhesive layer body 121, and the specific setting needs to be comprehensively considered in terms of thickness requirements, impact resistance and extrusion resistance requirements, and cost requirements of the actual product. The following mainly takes embedding a single layer of metal mesh 122 as an example for explanation. In other examples, two or three layers of metal mesh 122 may also be embedded as required, and this embodiment does not limit this.

[0069] In some examples, in order to better limit the flow of glue in the glue layer body 121, thereby alleviating the glue overflow problem, the metal mesh 122 can be embedded in the middle layer position between the first surface and the second surface of the glue layer body 121. For example, the metal mesh 122 can be arranged parallel to the metal layer 123, and along the direction perpendicular to the metal layer 123, the distance between the metal mesh 122 and the first surface of the glue layer body 121 is a first distance, and the distance between the metal mesh 122 and the second surface of the glue layer body 121 is a second distance, and the first distance is equal to the second distance.

[0070] Of course, in other examples, affected by the preparation process, or taking into account some other practical application requirements, the position of the metal mesh 122 may be relatively closer to the first surface, or relatively closer to the second surface in the direction perpendicular to the metal layer 123, and this embodiment does not limit this.

[0071] Taking the setting of a single-layer metal mesh 122 as an example, in some examples, the adhesive layer body 121 can be composed of adhesive layers applied twice. That is to say, the composite adhesive layer 120 may include: a first adhesive layer, a metal mesh 122 and a second adhesive layer stacked in sequence, and the first adhesive layer and the second adhesive layer constitute the above-mentioned adhesive layer body 121. The second adhesive layer is closer to the metal layer 123 than the first adhesive layer. For example, silicone is used as the material of the adhesive layer body 121. During the specific preparation, a layer of silicone can be applied first, and then a metal mesh 122 is laid on the layer of silicone, and then a layer of silicone is applied on the metal mesh 122 to obtain the composite adhesive layer 120. For example, the thickness of the first adhesive layer and the second adhesive layer in the direction perpendicular to the metal layer 123 can be equal, or there can be a slight difference.

[0072] Figure 3 A schematic diagram of an exemplary single-layer metal mesh 122 is shown. Figure 4 Shows Figure 3 A schematic diagram of a single grid 1221 in FIG. Figure 3 As shown, the metal mesh 122 is composed of a plurality of grids 1221. In some examples, the grids 1221 of the metal mesh 122 may be diamond grids. This is beneficial to increase the ability to resist impact or extrusion in a direction perpendicular to the metal layer 123 while ensuring the flexibility of the metal mesh 122. Of course, in other examples, the grids 1221 of the metal mesh 122 may also be other shapes, such as triangles, rectangles, pentagons, hexagons, etc., which are not limited in this embodiment.

[0073] In specific implementation, the size of a single grid 1221 in the metal mesh 122 can be determined according to the required buffering performance and the acceptable degree of glue overflow. It should be noted that the larger the size of a single grid 1221, the sparser the grid of the metal mesh 122, the smaller the elastic modulus of the entire composite adhesive layer 120, the softer it is, and the better the impact resistance; conversely, the smaller the size of a single grid 1221, that is, the denser the grid of the metal mesh 122, the better the ability to restrict lateral glue flow, the larger the elastic modulus of the entire composite adhesive layer 120, and the stronger the deformation resistance.

[0074] like Figure 4 As shown, the diamond grid 1221 includes two relative acute angles and two relative obtuse angles. In order to give full play to the deformation resistance of the material, in some examples, the angle of the two relative acute angles Φ can be greater than or equal to 80 degrees and less than 90 degrees, such as 80 degrees, 82 degrees, 85 degrees, 87 degrees, etc., which is not limited in this embodiment.

[0075] In some examples, in addition to improving the glue overflow problem, by covering the metal mesh 122 to the cutting line of the single heat dissipation film 12 during the preparation process of the heat dissipation film 12, the support performance at the cutting line position can be effectively increased, thereby reducing the edge collapse of the heat dissipation film 12 caused by the extrusion of the die during the cutting process, such as the wave-shaped concave-convex deformation, which is beneficial to improving the finished product yield of the heat dissipation film 12, and can also effectively improve the edge deformation caused by peeling off the protective film before the heat dissipation film 12 is attached to the display panel 11. Accordingly, in the single heat dissipation film 12 obtained after cutting, the edge 1220 of the metal mesh 122 is aligned with the edge of the metal layer 123 in the direction perpendicular to the metal layer 123. This is also beneficial to limit the glue overflow problem at the edge.

[0076] It is understandable that the size of the composite adhesive layer 120 in the heat dissipation film 12 is adapted to the size of the metal layer 123. When the heat dissipation film 12 is attached, under the pressure perpendicular to the direction of the display panel 11, the material of the adhesive layer body 121 is squeezed to produce lateral flow, resulting in side glue overflow. In order to effectively limit the above-mentioned lateral glue flow and improve the glue overflow problem, it is necessary to embed the metal mesh 122 at least in the edge area of ​​the adhesive layer body 121. In other words, the orthographic projection of the metal mesh 122 in the heat dissipation film 12 on the metal layer 123 at least covers the edge area of ​​the metal layer 123.

[0077] In some examples, the metal mesh 122 may be embedded in the entire layer, that is, the metal mesh 122 parallel to the metal layer 123 is embedded in the entire adhesive layer body 121. At this time, the orthographic projection of the metal mesh 122 in the heat dissipation film 12 on the metal layer 123 covers the entire metal layer 123. For example, Figure 2 The metal mesh 122 in the display device 10 shown is embedded in the adhesive layer body 121 as a whole layer. This is beneficial to better restrict the lateral adhesive flow, simplify the preparation process, and improve the thickness uniformity of the composite adhesive layer 120.

[0078] Of course, in other examples, in order to save materials, the metal mesh 122 may also be embedded only in the edge area of ​​the adhesive layer body 121. Figure 5 As shown, the metal mesh 122 is in a ring shape. For example, along a direction perpendicular to the metal layer 123, the edge 1220 (here, the outer edge) of the ring-shaped metal mesh 122 can be aligned with the edge of the metal layer 123, and the ring width can be designed according to actual needs.

[0079] For example, Figure 6 FIG. 2 shows a schematic diagram of a display device 20 provided in a comparative embodiment. Figure 6 As shown, the heat dissipation film 22 in the display device 20 includes a silicone layer 221 and a metal layer 222 which are stacked. The metal layer 222 is bonded to the backlight side of the display panel 21 through the silicone layer 221. Since the silicone layer 221 is relatively soft and its thickness is much greater than the thickness of the commonly used grid glue, when the heat dissipation film 22 is attached, it is subjected to the force perpendicular to the surface of the display panel 21, and the silicone is compressed and overflows from the side, resulting in a more serious glue overflow phenomenon. At this time, the side 2210 of the silicone layer 221 is an arc surface, and along the direction toward the backlight side of the display panel 11 (such as Figure 6The distance d′ between the side 2210 of the silicone layer 221 and the side of the metal layer 222 on the same side gradually increases, that is, the overflow of the silicone layer is serious. It should be noted that the silicone layer 221 has a certain thickness, the surface of the silicone layer 221 close to the display panel 21 is its first surface, and the surface close to the metal layer 222 is its second surface. The side 2210 of the silicone layer 221 refers to the surface located around the silicone layer 221 and adjacent to its first surface and second surface. The side of the metal layer 222 on the same side refers to the side of the metal layer facing the same side as the side of the silicone layer 221, such as Figure 6 The center is located on the left side.

[0080] In the heat dissipation film 12 provided in the embodiment of the present disclosure, when the composite adhesive layer 120 is squeezed in a direction perpendicular to the surface of the display panel 11, the presence of the metal mesh 122 will limit the lateral adhesive flow, that is, limit the overflow of the adhesive, thereby reducing the amount of adhesive overflow. Figure 2 As shown, the direction toward the backlight side of the display panel 11 (such as Figure 2 The side surface 1200 of the composite adhesive layer 120 refers to the surface located around the composite adhesive layer 120 and adjacent to the first surface and the second surface thereof. The side surface of the metal layer 123 refers to the side surface of the metal layer facing the same side as the side surface of the composite adhesive layer 120, such as Figure 6 That is to say, the overflowed glue layer shrinks inward at the metal mesh 122, so that the maximum overflow glue distance d is smaller than the maximum overflow glue distance d′ of the above comparative embodiment, that is, the overflow glue amount is reduced, which effectively improves the overflow glue problem caused by using the glue layer as a buffer while thinning the heat dissipation film.

[0081] Figure 7 FIG. 1 is a flow chart showing a method for preparing a heat dissipation film 12 provided in an embodiment of the present disclosure. The method for preparing a heat dissipation film 12 can be used to prepare the heat dissipation film 12 provided in the above embodiment. Figure 7 As shown, the method for preparing the heat dissipation film 12 may include the following steps:

[0082] Step S101, forming a first adhesive layer on the protective film;

[0083] Step S102, forming a metal mesh on the first adhesive layer;

[0084] Step S103, forming a second adhesive layer on the metal mesh;

[0085] Step S104: attaching a metal layer on the second adhesive layer.

[0086] For example, Figure 8As shown, the bottom protective film 800 can be laid first, and the first adhesive layer 801 can be scraped on the bottom protective film 800. Then, the metal mesh is stretched on the mesh stretching mechanism (i.e., tension F is applied all around), and the pre-prepared large-size metal mesh 802 is placed on the surface of the first adhesive layer 801; then, the second adhesive layer 803 is scraped on the metal mesh 802, and covered with the top protective film 804. After the glue is matured, the mesh stretching mechanism is withdrawn and the product is offline. For example, the materials of the first adhesive layer 801 and the second adhesive layer 803 can be silicone, and the material of the metal mesh 802 can be copper or stainless steel. Further, the top protective film 804 is peeled off, and the metal layer is bonded to the second adhesive layer 803. For example, the material of the metal layer can be copper or stainless steel.

[0087] In some examples, in order to improve production efficiency, a large-sized heat dissipation film can be prepared first, and then a plurality of small-sized single heat dissipation films can be obtained by cutting. That is, after the metal layer is attached to the second adhesive layer, a cutting step is further included, specifically including: cutting the stacked structure consisting of the metal layer, the second adhesive layer 803, the metal mesh 802, the first adhesive layer 801 and the bottom protective film 800 according to a predetermined cutting line to obtain Fig. 9 The metal mesh 802 covers the cutting line, which can enhance the strength of the cutting position, effectively reduce the deformation caused by the extrusion of the cutting die 900 during the cutting process, improve the yield rate of the finished product, and also help to improve the edge deformation caused by peeling the heat dissipation film from the bottom protective film 800 when the heat dissipation film is attached, thereby reducing the deformation at the edge of the heat dissipation film in the display device.

[0088] In the above description, the technical details such as the composition of each layer of the product are not described in detail. However, those skilled in the art should understand that various technical means can be used to form layers, regions, etc. of desired shapes. In addition, in order to form the same structure, those skilled in the art can also design methods that are not completely the same as the methods described above. Although each embodiment is described separately above, it does not mean that the measures in each embodiment cannot be used in combination to advantage.

[0089] In addition, those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure is limited to these examples. Based on the concept of the present disclosure, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of different aspects of one or more embodiments of the present disclosure as described above, which are not provided in detail for the sake of simplicity.

[0090] Although the preferred embodiments of the present disclosure have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present disclosure.

Claims

1. A heat dissipation film, characterized in that: include: A composite adhesive layer and a metal layer are stacked, wherein the composite adhesive layer comprises: an adhesive layer body and a metal mesh; The material of the adhesive layer body has bonding and stress buffering properties, the metal mesh is embedded between the first surface and the second surface of the adhesive layer body, and is configured to limit the flow of adhesive in the adhesive layer body in a direction parallel to the metal layer, wherein the first surface is a surface close to the metal layer, and the second surface is a surface away from the metal layer.

2. The heat dissipation film according to claim 1, characterized in that: The metal mesh is arranged parallel to the metal layer. Along the direction perpendicular to the metal layer, the distance between the metal mesh and the first surface of the adhesive layer body is a first distance, and the distance between the metal mesh and the second surface of the adhesive layer body is a second distance. The first distance is equal to the second distance.

3. The heat dissipation film according to claim 1, characterized in that: The composite adhesive layer comprises: a first adhesive layer, a metal mesh and a second adhesive layer which are stacked in sequence, and the first adhesive layer and the second adhesive layer constitute the adhesive layer body.

4. The heat dissipation film according to claim 1, characterized in that: The orthographic projection of the metal mesh on the metal layer covers the entire metal layer, or the orthographic projection of the metal mesh on the metal layer covers an edge region of the metal layer.

5. The heat dissipation film according to claim 1, characterized in that: Along a direction perpendicular to the metal layer, an edge of the metal mesh is aligned with an edge of the metal layer.

6. The heat dissipation film according to claim 1, characterized in that: The material of the adhesive layer body includes silica gel.

7. The heat dissipation film according to claim 1, characterized in that: The grid of the metal mesh is a diamond grid, and the angle between two relative acute angles in the diamond grid is greater than or equal to 80 degrees and less than 90 degrees.

8. The heat dissipation film according to claim 1, characterized in that: The heat dissipation film further comprises a protective film, and the protective film is attached to a side of the adhesive layer body away from the metal layer.

9. A display device, characterized in that: include: A display panel and a heat dissipation film as described in any one of claims 1 to 7, wherein the heat dissipation film is attached to the backlight side of the display panel via a composite adhesive layer.

10. The display device according to claim 9, characterized in that: Along the direction toward the backlight side of the display panel, the distance between the side surface of the composite adhesive layer and the side surface of the metal layer on the same side shows a trend of first increasing, then decreasing, and then increasing.

11. A method for preparing a heat dissipation film, characterized in that: For preparing the heat dissipation film according to any one of claims 1 to 8, the method comprises: forming a first adhesive layer on the protective film; forming a metal mesh on the first adhesive layer; forming a second adhesive layer on the metal mesh; A metal layer is attached on the second adhesive layer.

12. The method according to claim 11, characterized in that After the metal layer is attached to the second adhesive layer, the method further includes: The stacked structure composed of the metal layer, the second adhesive layer, the metal mesh, the first adhesive layer and the protective film is cut according to a predetermined cutting line to obtain a heat dissipation film, wherein the metal mesh covers the cutting line.

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