Electromagnetic shielding film and circuit board

Abstract

The invention discloses an electromagnetic shielding film and a circuit board, the electromagnetic shielding film comprises a shielding layer, a first conductive layer, a second conductive layer, a first release layer and a second release layer, the shielding layer comprises a first surface and a second surface which are arranged oppositely, and the first conductive layer is arranged on one side of the first surface; the second conductive layer is arranged on one side of the second surface; the first release layer is arranged on the side, away from the shielding layer, of the first conductive layer, the second release layer is arranged on the side, away from the second surface, of the second conductive layer, the first conductive layer is exposed after the first release layer is removed, and the second conductive layer is exposed after the second release layer is removed. According to the electromagnetic shielding film, the first conductive layer and the second conductive layer are arranged on the two sides of the shielding layer, so that the electromagnetic shielding film can achieve good conductive contact in the two directions of the shielding layer while reducing electromagnetic interference, and therefore, when the electromagnetic shielding film is installed on a circuit board, reliable electric connection can be formed between the electromagnetic shielding film and the circuit board and other different components, and the reliability of the electromagnetic shielding film is improved. And the reliability of the circuit board is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit boards, and in particular to an electromagnetic shielding film and a circuit board. Background Art

[0002] Currently, circuit boards are prone to problems such as insufficient strength and poor shielding effect during the design process, so the reliability of circuit boards is currently low. Summary of the invention

[0003] The main technical problem solved by the present application is to provide an electromagnetic shielding film and a circuit board, which can improve the reliability of the circuit board.

[0004] To solve the above technical problems, the present application adopts a technical solution: providing an electromagnetic shielding film, comprising a shielding layer, a first conductive layer, a second conductive layer, a first release layer and a second release layer, the shielding layer comprising a first surface and a second surface arranged opposite to each other, the first conductive layer being arranged on one side of the first surface of the shielding layer, the second conductive layer being arranged on one side of the second surface of the shielding layer, the first release layer being arranged on a side of the first conductive layer away from the shielding layer, wherein the first release layer is configured to be torn off to expose the first conductive layer, and the second release layer is arranged on a side of the second conductive layer away from the second surface, wherein the second release layer is configured to be torn off to expose the second conductive layer.

[0005] In order to solve the above-mentioned technical problems, the present application also provides a technical solution: a circuit board is provided, comprising a circuit board body, the above-mentioned electromagnetic shielding film and a reinforcement layer, wherein the electromagnetic shielding film is arranged on one side of the circuit board body, wherein the first release layer and the second release layer are removed, and the first conductive layer is electrically connected to the grounding point in the circuit board body; the reinforcement layer is arranged on the side of the electromagnetic shielding film away from the circuit board body, and the reinforcement layer is connected to the second conductive layer.

[0006] To solve the above technical problems, the present application also provides a technical solution: an electromagnetic shielding film is provided, comprising a carrier layer, a rigid layer, and a shielding layer stacked in sequence, wherein the hardness of the rigid layer is greater than that of the carrier layer and the shielding layer.

[0007] To solve the above technical problems, the present application also provides a technical solution: a circuit board is provided, comprising a circuit board body and the above-mentioned electromagnetic shielding film, wherein the electromagnetic shielding film is arranged on one side of the circuit board body, and the rigid layer is located on the side of the shielding layer away from the circuit board body.

[0008] Beneficial effect: The present application arranges a first conductive layer and a second conductive layer on opposite sides of the shielding layer, so that the electromagnetic shielding film can reduce electromagnetic interference while achieving good conductive contact in two directions of the shielding layer. Therefore, when the electromagnetic shielding film is installed on the circuit board, a reliable electrical connection can be formed between the circuit board and other different components, thereby improving the reliability of the entire circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0010] Figure 1 A schematic diagram of the structure of an electromagnetic shielding film provided in one embodiment of the present application;

[0011] Figure 2 A schematic diagram of the structure of a circuit board provided in one embodiment of the present application;

[0012] Figure 3 A schematic structural diagram of an electromagnetic shielding film provided in another embodiment of the present application;

[0013] Figure 4 A schematic diagram of the structure of a circuit board provided in another embodiment of the present application;

[0014] Figure 5 A schematic structural diagram of an electromagnetic shielding film provided in another embodiment of the present application;

[0015] Figure 6 A schematic diagram of the structure of a circuit board provided in another embodiment of the present application. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0017] The terms "first", "second", "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second", "third" can expressly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the embodiments of this application, all directional indications (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the steps or units listed, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0018] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0019] Please also read Figure 1 and Figure 2 In one embodiment of the present application, an electromagnetic shielding film 100 is provided, comprising a shielding layer 101, a first conductive layer 102, a second conductive layer 103, a first release layer 104, and a second release layer 105. The first release layer 104, the first conductive layer 102, the shielding layer 101, the second conductive layer 103, and the second release layer 105 are stacked in sequence, and the shielding layer 101 is located at the center of the electromagnetic shielding film 100, so that the entire electromagnetic shielding film 100 is symmetrically arranged with the shielding layer 101 as the center. The first release layer 104 is configured to be torn off from the first conductive layer 102, and the second release layer 105 is configured to be torn off from the second conductive layer 103, so that the first conductive layer 102 and the second conductive layer 103 can be adhered to the circuit board 200 or other components, thereby playing an electromagnetic shielding role on the circuit board 200 or other components to be adhered.

[0020] Specifically, the shielding layer 101 includes a first surface 1011 and a second surface 1012 disposed opposite to each other. The shielding layer 101 is located at the center of the electromagnetic shielding film 100 and is made of a metal material with good electrical conductivity, such as any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, so that the shielding layer 101 can effectively reflect and absorb electromagnetic waves, thereby achieving a shielding effect.

[0021] The first conductive layer 102 is disposed on one side of the first surface 1011 of the shielding layer 101, and the second conductive layer 103 is disposed on one side of the second surface 1012 of the shielding layer 101. The first conductive layer 102 and the second conductive layer 103 can connect the shielding layer 101 with an external circuit, ensuring that the electromagnetic shielding film 100 can form a good conductive contact with the circuit board 200 or other components, and the first conductive layer 102 and the second conductive layer 103 can further help the shielding layer 101 to be better grounded, thereby enhancing the shielding effect of the electromagnetic shielding film 100.

[0022] The first release layer 104 is disposed on a side of the first conductive layer 102 away from the shielding layer 101, wherein the first release layer 104 is configured to be removable to expose the first conductive layer 102. The first release layer 104 protects the first conductive layer 102 and can provide protection for subsequent processing of the electromagnetic shielding film 100. At the same time, the first release layer 104 can also prevent foreign matter, impurities, etc. from contaminating the first conductive layer 102.

[0023] The second release layer 105 is disposed on the side of the second conductive layer 103 away from the second surface 1012, wherein the second release layer 105 is configured to be removable to expose the second conductive layer 103. The second release layer 105 protects the second conductive layer 103 and can provide protection for subsequent processing of the electromagnetic shielding film 100. At the same time, the second release layer 105 can also prevent foreign matter, impurities, etc. from contaminating the second conductive layer 103.

[0024] Among them, when the electromagnetic shielding film 100 and the reinforcement layer 202 are installed on the circuit board 200, the first release layer 104 and the second release layer 105 are removed, and the electromagnetic shielding film 100 can achieve bidirectional conductivity. Therefore, the reinforcement layer 202 can be directly electrically connected to the grounding point in the circuit board 200, that is, the second metal layer 2015, through the electromagnetic shielding film 100, replacing the existing technology that requires window processing in the electromagnetic shielding film 100 and the second covering film 2016 to achieve grounding of the reinforcement layer 202.

[0025] In the above-mentioned electromagnetic shielding film 100, by arranging the first conductive layer 102 and the second conductive layer 103 on opposite sides of the shielding layer 101, the electromagnetic shielding film 100 can reduce electromagnetic interference while also achieving good conductive contact in two directions of the shielding layer 101. Therefore, when the electromagnetic shielding film 100 is installed on the circuit board 200, a reliable electrical connection can be formed between the circuit board 200 and other different components, thereby improving the reliability of the entire circuit board 200.

[0026] See also Figure 1 In one embodiment, the first conductive layer 102 is an adhesive layer, and the first conductive layer 103 is also an adhesive layer, so that after the first release layer 104 and the second release layer 105 are removed, the electromagnetic shielding film 100 can be bonded to the circuit board 200 and the reinforcement layer 202 through the first conductive layer 102 and the second conductive layer 103, thereby improving the convenience of installation.

[0027] In other embodiments, the first conductive layer 102 may not be a glue layer, and the second conductive layer 103 may not be a glue layer. In this case, the electromagnetic shielding film 100 may be fixedly connected to the circuit board 200 and the reinforcement layer 202 by a structure such as double-sided tape.

[0028] Or in other implementations, one of the first conductive layer 102 and the second conductive layer 103 is a glue layer, and the other is not a glue layer.

[0029] Please continue reading Figure 1 In one embodiment, the first conductive layer 102 and the second conductive layer 103 are made of the same material, which improves the convenience of preparing the electromagnetic shielding film 100. In other embodiments, the first conductive layer 102 and the second conductive layer 103 may also be prepared using different materials.

[0030] Please continue reading Figure 1 In one embodiment, the material of the first conductive layer 102 and the second conductive layer 103 includes at least one of resin and conductive glue.

[0031] When the material of the first conductive layer 102 and the second conductive layer 103 is resin, the material of the resin can be one of epoxy resin, acrylic resin, and polyurethane resin. The epoxy resin, acrylic resin, and polyurethane resin mentioned here can be modified epoxy resin, modified acrylic resin, or modified polyurethane resin to which a curing agent, a leveling agent, and a dispersant are added.

[0032] When the material of the first conductive layer 102 and the second conductive layer 103 is conductive glue, the conductive glue includes an adhesive layer containing conductive particles to improve the conductivity of the conductive glue, thereby further ensuring that the shielding layer 101 is connected to the ground point of the circuit board 200 .

[0033] Please continue reading Figure 1 In one embodiment, the thickness of the first conductive layer 102 is the same as the thickness of the second conductive layer 103, so as to ensure the symmetry and uniformity of the electromagnetic shielding film 100, thereby improving the stability of the overall structure, and the same thickness can simplify the preparation process and reduce the preparation cost. In other embodiments, the thickness of the first conductive layer 102 and the thickness of the second conductive layer 103 can also be set to different thicknesses according to specific needs.

[0034] Please continue reading Figure 1 In one embodiment, the thickness d1 of the first conductive layer 102 and the second conductive layer 103 ranges from 5 to 10 μm. For example, the thickness d1 of the first conductive layer 102 and the second conductive layer 103 is 5 μm, 7 μm or 10 μm. In this embodiment, the thickness d1 of the first conductive layer 102 and the second conductive layer 103 are both 5 μm.

[0035] Please continue reading Figure 1 In one embodiment, the orthographic projection of the first conductive layer 102 on the shielding layer 101 coincides with the orthographic projection of the second conductive layer 103 on the shielding layer 101. The above arrangement can make the first conductive layer 102 and the second conductive layer 103 completely symmetrical on both sides of the shielding layer 101, thereby improving the flatness of the entire electromagnetic shielding film 100.

[0036] Please continue reading Figure 1 In one embodiment, the orthographic projections of the first conductive layer 102 and the second conductive layer 103 on the shielding layer 101 cover the shielding layer 101. The first conductive layer 102 and the second conductive layer 103 completely cover the shielding layer 101, which can enhance the electromagnetic shielding effect and ensure the effective use of the entire shielding area, thereby reducing electromagnetic interference and reducing the risk of shielding performance degradation due to partial exposure of the shielding layer 101.

[0037] It should be noted that, in other embodiments, only the orthographic projection of the first conductive layer 102 on the shielding layer 101 may cover the shielding layer 101, and in this case, the orthographic projection of the second conductive layer 103 on the shielding layer 101 cannot completely cover the shielding layer 101. Alternatively, only the orthographic projection of the second conductive layer 103 on the shielding layer 101 may cover the shielding layer 101, and in this case, the orthographic projection of the first conductive layer 102 on the shielding layer 101 cannot completely cover the shielding layer 101.

[0038] Please refer again Figure 1 and Figure 2The present application also provides a circuit board 200, which includes a circuit board body 201, the electromagnetic shielding film 100 and a reinforcement layer 202. The electromagnetic shielding film 100 is arranged on one side of the circuit board body 201, and the reinforcement layer 202 is arranged on the side of the electromagnetic shielding film 100 away from the circuit board body 201. The electromagnetic shielding film 100 is used to reduce electromagnetic interference for the circuit board 200, and the reinforcement layer 202 can improve the strength of the circuit board 200.

[0039] Specifically, the first release layer 104 and the second release layer 105 in the electromagnetic shielding film 100 are removed, and the first conductive layer 102 is electrically connected to the ground point in the circuit board body 201. By directly connecting the first conductive layer 102 to the ground point of the circuit board body 201, effective grounding can be achieved, thereby reducing signal reflection and crosstalk and improving shielding performance.

[0040] The reinforcing layer 202 is disposed on the side of the electromagnetic shielding film 100 away from the circuit board body 201, and the reinforcing layer 202 is connected to the second conductive layer 103. The reinforcing layer 202 can improve the overall rigidity and bending strength of the circuit board 200, reduce the risk of deformation of the circuit board 200 due to external force, and at the same time, the reinforcing layer 202 can also protect the electromagnetic shielding film 100 from external wear or damage.

[0041] In the above-mentioned circuit board 200, by electrically connecting the first conductive layer 102 to the grounding point in the circuit board body 201, and electrically connecting the second conductive layer 103 to the reinforcement layer 202, the double-sided conductive function of the electromagnetic shielding film 100 makes it unnecessary to open a window on the electromagnetic shielding film 100 during the preparation of the circuit board 200 to achieve electrical connection between the reinforcement layer 202 and the grounding point in the circuit board body 201. The prepared circuit board 200 can simultaneously have good electromagnetic shielding performance and anti-bending performance, thereby improving the product reliability of the entire circuit board 200.

[0042] See also Figure 2 In one embodiment, the material of the reinforcement layer 202 includes stainless steel. Stainless steel has high mechanical strength and hardness, which can significantly improve the structural stability of the circuit board 200 and reduce the damage of the circuit board 200 caused by external pressure or vibration. At the same time, the reinforcement layer 202 made of stainless steel itself has a certain conductivity, and when forming a continuous shielding path with the first conductive layer 102 and the second conductive layer 103, it can enhance the electromagnetic shielding effect of the circuit board 200.

[0043] In one embodiment, the circuit board body 201 includes a flexible circuit board. In other embodiments, the circuit board body 201 may also include a rigid circuit board.

[0044] Please continue reading Figure 2In one embodiment, the circuit board body 201 includes a device layer 2011, a first cover film 2012, a first metal layer 2013, a substrate layer 2014, a second metal layer 2015, and a second cover film 2016 stacked in sequence, and the electromagnetic shielding film 100 is disposed on a side of the second cover film 2016 away from the second metal layer 2015. The first metal layer 2013 and the second metal layer 2015 are both provided with grounding points, the device layer 2011 is electrically connected to the grounding point of the first metal layer 2013 through the first cover film 2012, and the first conductive layer 102 in the electromagnetic shielding film 100 is electrically connected to the grounding point in the second metal layer 2015 through the second cover film 2016.

[0045] Through the above configuration, the first conductive layer 102 is electrically connected to the ground point in the second metal layer 2015 through the second covering film 2016 to form an effective ground path, which helps to reduce electromagnetic interference in the circuit board body 201 and improve the product reliability of the circuit board 200.

[0046] In one embodiment, the material of the substrate layer 2014 includes polyimide.

[0047] In one embodiment, the material of the first metal layer 2013 and the second metal layer 2015 may be copper or other metal materials, which is not limited here.

[0048] Please continue reading Figure 2 In one embodiment, the first covering film 2012 and the second covering film 2016 are made of at least one of polyester film and polypropylene film. The first covering film 2012 and the second covering film 2016 are used to protect the circuit board body 201 from corrosion by foreign substances, thereby increasing the reliability and service life of the circuit board 200.

[0049] When the electromagnetic shielding film 100 is pressed onto the circuit board body 201, the first conductive layer 102 contacts the second covering film, and the first conductive layer 102 is electrically connected to the grounding point of the second metal layer 2015 through the second covering film 2016, that is, the first conductive layer 102 is electrically connected to the grounding point of the circuit board body 201, thereby achieving the purpose of shielding electromagnetic wave interference.

[0050] See also Figure 3Another technical solution adopted by the present invention is: to provide an electromagnetic shielding film 300, comprising a carrier layer 301, a rigid layer 302, and a shielding layer 303 stacked in sequence. Among them, the hardness of the rigid layer 302 is greater than that of the carrier layer 301 and the shielding layer 303. The shielding layer 303 is used to reduce electromagnetic interference, and the rigid layer 302 has a protective effect to ensure that the shielding layer 303 is not scratched or damaged during use, thereby maintaining the high shielding effectiveness of the shielding layer 303. The carrier layer 301 supports the rigid layer 302, further improving the structural strength of the electromagnetic shielding film 300.

[0051] In the electromagnetic shielding film 300, the shielding layer 303 is flattened by providing the rigid layer 302, which helps to improve the electromagnetic shielding effect. At the same time, the rigid layer 302 can protect the shielding layer 303 from external factors, reduce the wear or scratches of the shielding layer 303, and thus maintain the shielding performance of the shielding layer 303.

[0052] In one embodiment, the shielding layer 303 is located at the center of the electromagnetic shielding film 300 and is made of a metal material with good conductivity, such as any one of aluminum, titanium, zinc, iron, nickel, chromium, cobalt, copper, silver and gold, so that the shielding layer 303 can effectively reflect and absorb electromagnetic waves, thereby achieving a shielding effect.

[0053] In one embodiment, the material of the carrier layer 301 includes at least one of a polyester film and a polyimide film. The carrier film plays a supporting role and provides protection for the electromagnetic shielding film 300 during transportation or processing.

[0054] In one embodiment, the material of the rigid layer 302 includes an insulating material. The rigid layer 302 of the insulating material generally has a higher mechanical strength, which can improve the rigidity and durability of the entire electromagnetic shielding film 300 .

[0055] In one embodiment, the material of the rigid layer 302 includes polyimide.

[0056] It is understandable that the shielding layer 303 is made of metal. In theory, the hardness of the metal is greater than the hardness of the rigid layer 302 (the material of the rigid layer 302 is polyimide). At this time, the thickness of the shielding layer 303 needs to be less than the thickness of the rigid layer 302, so that there is a difference in hardness between the shielding layer 303 and the rigid layer 302. In actual application, the thickness of the rigid layer 302 can be selected according to actual conditions, and is not limited here.

[0057] In another embodiment, the material of the rigid layer 302 includes a conductive material, and the rigid layer 302 is electrically connected to the shielding layer 303. The rigid layer 302 made of conductive material is electrically connected to the shielding layer 303 to form a continuous conductive path, which helps to enhance the electromagnetic shielding effect and thus reduce electromagnetic interference.

[0058] In one embodiment, the material of the rigid layer 302 includes stainless steel.

[0059] In one embodiment, the hardness of the rigid layer 302 is in the range of 200-250 HV, for example, the hardness of the rigid layer 302 is 200 HV, 225 HV or 250 μm, which is not limited herein.

[0060] In one embodiment, the thickness d2 of the rigid layer 302 is in the range of 50-100 μm, for example, the thickness d2 of the rigid layer 302 is 50 μm, 70 μm or 100 μm, which is not limited herein.

[0061] Please continue reading Figure 3 In one embodiment, the orthographic projection of the rigid layer 302 on the shielding layer 303 covers the shielding layer 303. The rigid layer 302 completely covers the shielding layer 303, which can improve the rigidity of the electromagnetic shielding film 300, thereby reducing the bending of the shielding layer 303, thereby reducing the risk of reduced flatness due to partial exposure of the shielding layer 303.

[0062] Please also read Figure 3 and Figure 4 In one embodiment, the electromagnetic shielding film 300 further includes a conductive adhesive layer 304, which is disposed on the side of the shielding layer 303 away from the rigid layer 302. The conductive adhesive layer 304 is mainly responsible for connecting the shielding layer 303 with the external circuit to ensure that the electromagnetic shielding film 300 can form a good conductive contact with the circuit board 400 or other components. At the same time, the conductive adhesive layer 304 can further help the shielding layer 303 to be better grounded, thereby enhancing the shielding effect of the electromagnetic shielding film 300.

[0063] In one embodiment, the material of the conductive adhesive layer 304 includes at least one of resin and conductive particles, which is not limited here.

[0064] Please refer again Figure 3 In one embodiment, the electromagnetic shielding film 300 further includes a release layer 305, which is disposed on the side of the conductive adhesive layer 304 away from the shielding layer 303. After the release layer 305 is removed, the conductive adhesive layer 304 is exposed. The release layer 305 protects the conductive adhesive layer 304 and can provide protection for subsequent processing of the electromagnetic shielding film 300. At the same time, the release layer 305 can also prevent foreign matter, impurities, etc. from contaminating the conductive adhesive layer 304.

[0065] In one embodiment, the material of the release layer 305 includes at least one of a polyester film and a polyimide film, which is not limited herein.

[0066] Please refer again Figure 3 and Figure 4The present application further provides a circuit board 400, comprising a circuit board body 401 and the above-mentioned electromagnetic shielding film 300, wherein the electromagnetic shielding film 300 is arranged on one side of the circuit board body 401. The rigid layer 302 is located on the side of the shielding layer 303 away from the circuit board body 401.

[0067] The conductive adhesive layer 304 in the electromagnetic shielding film 300 is electrically connected to the grounding point of the circuit board body 401. The rigid layer 302 is arranged on the side of the shielding layer 303 away from the circuit board body 401, so that the metal layer in the circuit board body 401 can be electrically connected to it, thereby facilitating the discharge of static electricity.

[0068] In the above-mentioned circuit board 400, by setting a rigid layer 302 and a shielding layer 303 in the electromagnetic shielding film 300, the electromagnetic shielding film 300 shell takes into account both reinforcement and shielding functions, eliminating the need to set up additional reinforcement components in the circuit board 400, simplifying the design and process flow of the entire circuit board 400, thereby saving preparation costs.

[0069] In one embodiment, the circuit board body 401 includes a flexible circuit board. In other embodiments, the circuit board body 401 may also include a rigid circuit board.

[0070] See also Figure 4 In one embodiment, the circuit board body 401 includes a device layer 4011, a first cover film 4012, a first metal layer 4013, a substrate layer 4014, a second metal layer 4015, and a second cover film 4016 stacked in sequence, and the electromagnetic shielding film 300 is disposed on a side of the second cover film 4016 away from the second metal layer 4015. The first metal layer 4013 and the second metal layer 4015 are both provided with grounding points, the device layer 4011 is electrically connected to the grounding point of the first metal layer 4013 through the first cover film 4012, and the conductive adhesive layer 304 in the electromagnetic shielding film 300 is electrically connected to the grounding point in the second metal layer 4015 through the second cover film 4016.

[0071] Through the above configuration, the conductive adhesive layer 304 is electrically connected to the grounding point in the second metal layer 4015 through the second covering film 4016 to form an effective grounding path, which helps to reduce electromagnetic interference in the circuit board body 401 and improve the product reliability of the circuit board 400.

[0072] In one embodiment, the material of the substrate layer 4014 includes polyimide.

[0073] In one embodiment, the material of the first metal layer 4013 and the second metal layer 4015 may be copper or other metal materials, which is not limited here.

[0074] Please continue reading Figure 4In one embodiment, the first covering film 4012 and the second covering film 4016 are made of at least one of polyester film and polypropylene film. The first covering film 4012 and the second covering film 4016 are used to protect the circuit board body 401 from corrosion by external substances, thereby increasing the reliability and service life of the circuit board 400.

[0075] When the electromagnetic shielding film 300 is pressed onto the circuit board body 401, the conductive adhesive layer 304 contacts the second covering film 4016, and the conductive adhesive layer 304 is electrically connected to the grounding point of the second metal layer 4015 through the second covering film 4016, that is, the conductive adhesive layer 304 is electrically connected to the grounding point of the circuit board body 401, thereby achieving the purpose of shielding electromagnetic wave interference.

[0076] Please also read Figure 5 and Figure 6 Another technical solution adopted by the present invention is to provide an electromagnetic shielding film 500, including a carrier layer 501, an insulating layer 502, a shielding layer 503, a conductive adhesive layer 504 and a release layer 505 stacked in sequence. Through the shielding layer 503 in the electromagnetic shielding film 500, the electromagnetic shielding film 500 can have the function of shielding electromagnetic wave interference, so that the electromagnetic shielding film 500 can adhere to the circuit board 600 or other components after the release layer 505 is torn off, and realize the electromagnetic shielding effect on the circuit board 600 and other components.

[0077] Please continue reading Figure 5 and Figure 6 The present application also provides a circuit board 600, including a circuit board body 601, a reinforcement layer 602 and the above-mentioned electromagnetic shielding film 500, the reinforcement layer 602 is arranged on one side of the circuit board body 601, and the reinforcement layer 602 is electrically connected to the grounding point in the circuit board body 601, the electromagnetic shielding film 500 is arranged on the side of the reinforcement layer 602 away from the circuit board body 601, and after the release layer 505 of the electromagnetic shielding film 500 is torn off, the conductive adhesive layer 504 is directly attached to the reinforcement layer 602.

[0078] In the above-mentioned circuit board 600, the reinforcement layer 602 is directly electrically connected to the grounding point in the circuit board body 601, and the electromagnetic shielding film 500 plays a role in shielding electromagnetic waves, so that the entire circuit board 600 has both rigidity and electromagnetic shielding effects, thereby making the prepared circuit board 600 product highly reliable.

[0079] In one embodiment, the circuit board body 601 includes a flexible circuit board. In other embodiments, the circuit board body 601 may also include a rigid circuit board.

[0080] Please continue reading Figure 5 and Figure 6In one embodiment, the circuit board body 601 includes a device layer 6011, a first cover film 6012, a first metal layer 6013, a substrate layer 6014, a second metal layer 6015, and a second cover film 6016 stacked in sequence, and the reinforcement layer 602 is disposed on a side of the second cover film 6016 away from the second metal layer 6015. The first metal layer 6013 and the second metal layer 6015 are both provided with grounding points, the device layer 6011 is electrically connected to the grounding point of the first metal layer 6013 through the first cover film 6012, and the reinforcement layer 602 is electrically connected to the grounding point in the second metal layer 6015 through the second cover film 6016. The electromagnetic shielding film 500 is disposed on a side of the reinforcement layer 602 away from the second cover film 6016. The reinforcing layer 602 is directly electrically connected to the ground point in the second metal layer 6015 through the second covering film 6016 . The electromagnetic shielding film 500 plays a role in shielding electromagnetic waves, so that the entire circuit board 600 has both rigidity and electromagnetic shielding effects.

[0081] The above are only implementation methods of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An electromagnetic shielding film, characterized in that: include: A shielding layer, comprising a first surface and a second surface disposed opposite to each other; A first conductive layer, disposed on one side of the first surface of the shielding layer; A second conductive layer is disposed on one side of the second surface of the shielding layer; A first release layer is disposed on a side of the first conductive layer facing away from the shielding layer, wherein the first release layer is configured to be torn off to expose the first conductive layer; The second release layer is disposed on a side of the second conductive layer facing away from the second surface, wherein the second release layer is configured to be torn off to expose the second conductive layer.

2. The electromagnetic shielding film according to claim 1, characterized in that The first conductive layer is a glue layer, and / or the second conductive layer is a glue layer; Preferably, the first conductive layer and the second conductive layer are made of the same material; Preferably, the material of the first conductive layer / the second conductive layer includes at least one of resin and conductive glue.

3. The electromagnetic shielding film according to claim 1, characterized in that The thickness of the first conductive layer is the same as the thickness of the second conductive layer; Preferably, the thickness of the first conductive layer / the second conductive layer is in the range of 5-10 μm; Preferably, the orthographic projection of the first conductive layer on the shielding layer coincides with the orthographic projection of the second conductive layer on the shielding layer; Preferably, the orthographic projection of the first conductive layer / the second conductive layer on the shielding layer covers the shielding layer.

4. A circuit board, characterized in that: The circuit board comprises: Circuit board body; The electromagnetic shielding film according to any one of claims 1 to 3, arranged on one side of the circuit board body, wherein the first release layer and the second release layer are removed, and the first conductive layer is electrically connected to a ground point in the circuit board body; The reinforcing layer is arranged on a side of the electromagnetic shielding film away from the circuit board body, and the reinforcing layer is connected to the second conductive layer.

5. The circuit board according to claim 4, characterized in that: The material of the reinforcement layer includes stainless steel; Preferably, the circuit board body comprises a flexible circuit board.

6. An electromagnetic shielding film, characterized in that: The invention comprises a carrier layer, a rigid layer and a shielding layer which are stacked in sequence, wherein the rigid layer has a harderness than that of the carrier layer and the shielding layer.

7. The electromagnetic shielding film according to claim 6, characterized in that The material of the rigid layer includes insulating material; Preferably, the material of the rigid layer includes polyimide.

8. The electromagnetic shielding film according to claim 6, characterized in that The material of the rigid layer includes a conductive material, and the rigid layer is electrically connected to the shielding layer; Preferably, the material of the rigid layer includes stainless steel.

9. The electromagnetic shielding film according to claim 6, characterized in that The hardness range of the rigid layer is 200-250HV; Preferably, the thickness of the rigid layer is in the range of 50-100 μm; Preferably, the orthographic projection of the rigid layer on the shielding layer covers the shielding layer; Preferably, the electromagnetic shielding film further comprises: A conductive adhesive layer, arranged on a side of the shielding layer away from the rigid layer; A release layer, arranged on a side of the conductive adhesive layer away from the shielding layer; Preferably, the material of the release layer includes at least one of a polyester film and a polyimide film.

10. A circuit board, characterized in that: include: Circuit board body; The electromagnetic shielding film as described in any one of claims 6 to 9 is arranged on one side of the circuit board body; the rigid layer is located on the side of the shielding layer away from the circuit board body.

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