CN111148426A - Electromagnetic shielding film with high shielding performance and production process thereof - Google Patents
Electromagnetic shielding film with high shielding performance and production process thereof Download PDFInfo
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- CN111148426A CN111148426A CN202010046903.9A CN202010046903A CN111148426A CN 111148426 A CN111148426 A CN 111148426A CN 202010046903 A CN202010046903 A CN 202010046903A CN 111148426 A CN111148426 A CN 111148426A
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Classifications
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
- H05K9/0086—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising a single discontinuous metallic layer on an electrically insulating supporting structure, e.g. metal grid, perforated metal foil, film, aggregated flakes, sintering
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K1/00—Printed circuits
- H05K1/02—Details
- H05K1/0213—Electrical arrangements not otherwise provided for
- H05K1/0216—Reduction of cross-talk, noise or electromagnetic interference
Abstract
The invention relates to the technical field of electromagnetic shielding films for flexible circuit boards, in particular to an electromagnetic shielding film with high shielding performance and a production process thereof, and the technical scheme is as follows: the insulating layer, the metal shielding layer and the conductive adhesive layer are sequentially arranged, one side of the insulating layer is in a network shape, and one side of the metal shielding layer, which is connected with the insulating layer, is in a network shape matched with the insulating layer. According to the electromagnetic shielding film with high shielding performance and the production process thereof, the unique shielding body structure enables the shielding effectiveness of the electromagnetic shielding film to be as high as 75 db. Meanwhile, the metal shielding layer filled on one side of the latticed insulating layer has special latticed process characteristics, is different from the structural characteristics of the conventional rigid flat metal shielding layer, can enable the bending resistance of the metal shielding layer to be more outstanding, and shows excellent flexibility. In addition, compared with similar products, the method has the advantages of simple process, easy implementation, relatively lower cost and more mass production.
Description
Technical Field
The invention relates to the technical field of electromagnetic shielding films for flexible circuit boards, in particular to an electromagnetic shielding film with high shielding performance and a production process thereof.
Background
With the rapid development of modern electronic industrialization, a large number of electronic and electric devices are widely applied to industrial production and daily life of people, thereby greatly promoting the development of industrial technology and improving the quality of life of people. However, the electronic and electric devices radiate a large amount of electromagnetic waves during use, which causes considerable harm to the normal operation of the electronic devices and the living environment of human beings. Therefore, prevention of pollution by electromagnetic waves has become one of the major hotspots of scientific research today. The damage of electromagnetic radiation to electronic equipment is mainly represented by interference of electromagnetic waves to the electronic equipment or electronic components, or information leakage caused by electromagnetic waves radiated by a digital transmission system. The harm of electromagnetic waves to human health is manifested as various diseases induced by long-term radiation of electromagnetic waves. Therefore, how to effectively inhibit the interference of electromagnetic wave radiation on electronic and electrical equipment and protect human beings from the harm of electromagnetic wave radiation has become one of the important tasks of scientific research and industrial product development in the 21 st century.
The simplest and most effective method for suppressing electromagnetic radiation is to use a shielding material to suppress the radiation of electromagnetic waves. The shielding material reflects electromagnetic waves through impedance difference with air or attenuates eddy currents of the electromagnetic waves through self electromagnetic induction so as to achieve the purpose of absorption. At present, in the flexible circuit board industry, electromagnetic noise radiation from different signals between boards is mainly suppressed by attaching an electromagnetic shielding film.
The shielding effectiveness of the electromagnetic shielding film in the prior art is generally about 40-60 dB. For example, chinese patent application publication No. CN106003916A discloses an electromagnetic shielding film, and the shielding effectiveness of various embodiments described in the specification is between 50 dB and 60 dB. In order to enhance the shielding effect of the electromagnetic shielding film, part of manufacturers of the electromagnetic shielding film achieve the purpose of high shielding by increasing the thickness of the adhesive layer and the metal layer, for example, the chinese utility model patent with patent publication No. CN207070596U discloses a technical scheme of setting the metal shielding layer into multiple layers in the specification. However, this results in a complex process on the one hand and also in a considerable increase in material and production costs. On the other hand, the thicker metal layer has increased rigidity, so that the metal layer of the electromagnetic shielding film is likely to be brittle after the flexible wiring board is bent many times, thereby reducing the shielding performance and increasing the grounding resistance.
The present patent application was made based on this.
Disclosure of Invention
In view of the defects in the prior art, one of the design objectives of the present invention is to provide an electromagnetic shielding film with a relatively thin thickness, high electromagnetic shielding performance, and good bending resistance.
The technical purpose of the invention is realized by the following technical scheme: the utility model provides an electromagnetic shielding film of high shielding performance, is including insulating layer, metallic shield layer and the conducting glue layer that sets gradually, insulating layer one side is the network form, the metallic shield layer is the network form with insulating layer looks adaptation with the one side that the insulating layer is connected.
By adopting the technical scheme, compared with the prior art, one side of the insulating layer is designed into a grid shape, one side of the metal shielding layer is filled in grid gaps of the insulating layer and becomes the grid-shaped metal shielding layer, and the side of the metal shielding layer, which is far away from the insulating layer, is provided with the conductive adhesive layer. The grid-shaped metal shielding layer and the conductive adhesive layer conduct and ground the circuit of the circuit board. In addition, the grid-shaped metal shielding layer and the conductive adhesive layer form a continuous, complete and three-dimensional grid-shaped electromagnetic wave shielding body structure, electromagnetic waves can be reflected or inhibited in the grid-shaped shielding layer for two times, and the conductive adhesive layer leads away and releases redundant charges. The unique shield structure enables the shielding effectiveness of the electromagnetic shielding film of the present invention to be as high as 75 db. The latticed metal layer structure can avoid the adverse effect of brittle failure of the metal layer during bending. The electromagnetic shielding film has more outstanding bending resistance and shows excellent flexibility. The insulating layer is used for preventing charge overflow, and the occurrence of creepage, short circuit and the like can be reduced.
Preferably, the electromagnetic shielding film further comprises a carrier film, and the carrier film is arranged on one side of the grid insulating layer far away from the metal shielding layer.
Through adopting above-mentioned technical scheme, the carrier membrane can play the supporting role to and can provide the protection for the transportation process or the course of working of insulating layer.
Preferably, the carrier film is made of a non-silicon release film, and the carrier film is a polyester film or a polyimide film.
By adopting the technical scheme, the polyester film or the polyimide film is selected to have the main function of being favorable for better connecting the carrier film and the insulating layer, and the non-silicon release film formed by coating the non-silicon release agent on the polyester film or the polyimide has better release and better separation effects compared with the release film of an organic silicon system formed by coating the organic silicon release agent on the common release film. If the carrier film uses the release film of an organic silicon system, the organic silicon release agent needs to be attached to the insulating layer, and at the moment, the risk of silicon transfer exists, namely, a certain amount of silicon molecules are transferred to the surface of the insulating layer, and the printing performance of the surface of the insulating layer is reduced due to the silicon molecules, so that the insulating layer is not favorably printed, and the risk does not exist when the non-silicon release film is used.
Preferably, the thickness of the carrier film is between 30 μm and 80 μm.
Preferably, the electromagnetic shielding film further comprises a protective film, and the protective film is arranged on one side of the conductive adhesive layer, which is far away from the metal shielding layer.
By adopting the technical scheme, the protective film has a protective effect on the conductive adhesive layer and can be used for subsequent processing protection of products. In addition, foreign matters or impurities can be prevented from polluting the conductive adhesive layer.
Preferably, the protective film is a release film of an organosilicon system.
By adopting the technical scheme, the cost price of the release film of the organic silicon system is about 1-2 yuan/square meter, the cost is relatively low, and the performance requirements of the protective film in all aspects can be met.
Preferably, the protective film is a polyester film or a polyimide film.
By adopting the technical scheme, the polyester film or the polyimide film is easily obtained on the market and is a better protective film material.
Preferably, the thickness of the protective film is 50 μm to 80 μm.
Preferably, the insulating layer is made of a resin material.
By adopting the technical scheme, the insulating layer made of the resin can be well processed into the latticed side surface, and the other side surface can be well bonded with the carrier film. Compared with other materials, the latticed side surface processed by the resin has the advantages of good compliance and filling property, and better reflow soldering resistance.
Preferably, the resin for preparing the insulating layer is one of acrylic resin, polyurethane and epoxy resin.
By adopting the technical scheme, the acrylic resin, the polyurethane and the epoxy resin are cheap and easy to obtain and process, and the manufacturing cost of the protective film is lower by selecting the resins.
Preferably, the side of the outer surface of the insulating layer facing away from the grid provides a printable property.
By adopting the technical scheme, the side with printability can be printed with various ink characters.
Preferably, the thickness of the insulating layer is between 3 μm and 15 μm.
Preferably, the metal shielding layer is a composite metal layer made of two different conductive metal materials.
By adopting the technical scheme, the shielding performance, the corrosion resistance and the oxidation resistance of the double-layer metal layer made of different materials are more outstanding.
Preferably, the conductive metal material may be one of nickel, chromium, copper, silver and gold.
By adopting the technical scheme, the conductivity of the nickel and the copper is good, the conductivity requirement of the metal layer can be met, the cost is low, and the processes of copper electroplating and nickel electroplating are simple; the chromium has better wear resistance while meeting the conductive performance; the stability, wear resistance and conductivity of gold and silver are all on a high level.
Preferably, the thickness of the metal shielding layer is 0.1 μm to 5 μm.
Preferably, the conductive adhesive layer is an all-dimensional conductive adhesive layer.
By adopting the technical scheme, the omnibearing conductive adhesive can further reflect electromagnetic waves or attenuate electromagnetic waves, and the electromagnetic shielding performance is improved, because the omnibearing conductive adhesive layer can conduct electricity in the X direction, the Y direction and the Z direction, a certain amount of reflection can be generated when a part of electromagnetic waves meet the conductive particles in the X direction and the Y direction, and the electromagnetic waves reflected by the conductive adhesive can be absorbed by the metal layer again, so that the effect of enhancing the shielding effectiveness of the shielding film is achieved.
Preferably, the conductive adhesive layer is filled with conductive particles, and the conductive particles may be nickel, copper, silver, gold, or at least one of nickel-clad copper, silver-clad copper, and silver-clad graphite.
By adopting the technical scheme, the conductive performance of the nickel and the copper is excellent, the cost is low, the conductive particles can better meet the conductive requirement, the electromagnetic shielding effect is realized, the silver and the gold are used as the conductive particles in the conductive adhesive layer, the conductive effect is the best, and the conductive stability is the best.
Preferably, the particle diameter of the conductive particles is selected to be between 1 μm and 20 μm, and the filling ratio of the conductive particles to the conductive adhesive can be between 10% and 40%.
By adopting the technical scheme, the particle size and the filling ratio of the conductive particles are selected to be related to the whole conductive performance of the conductive adhesive layer, if the particle size of the conductive particles is too small, the conductive particles are difficult to be cross-linked together to realize the conductive function, and if the particle size of the conductive particles is too large, the conductive adhesive performance is insufficient, and the conductive particles cannot be well attached to the position needing to be attached. The filling ratio of the conductive particles in the conductive adhesive is not too large, the content of the conductive adhesive is lower due to the too large filling ratio of the conductive particles, the viscosity of the conductive adhesive is insufficient, the filling ratio of the conductive particles in the conductive adhesive is also not too small, and the whole conductive performance of the conductive adhesive layer is insufficient due to the too small filling ratio of the conductive particles. The filling ratio and the particle size of the conductive particles are selected within the range recorded in the application document, so that the conductive performance of the conductive adhesive layer can be ensured, and the effect of improving the shielding effectiveness of the electromagnetic shielding film is achieved.
Preferably, the thickness of the conductive adhesive layer is between 3 μm and 20 μm.
The second objective of the present invention is to provide a process for producing an electromagnetic shielding film, which is simple and easy to implement, and has relatively lower cost and mass production.
The technical purpose of the invention is realized by the following technical scheme, and the production process of the electromagnetic shielding film comprises the following specific process steps:
step a, coating insulating resin on one side of a carrier film to form a grid-shaped insulating layer;
step b, electroplating conductive metal on one latticed side of the latticed insulating layer to form a latticed metal shielding layer;
c, coating conductive adhesive on one side of the surface of the grid metal shielding layer, which is far away from the insulating layer, to form a conductive adhesive layer;
and d, forming a protective film on one side of the surface of the conductive adhesive layer, which is far away from the metal shielding layer, in a laminating manner.
Through the technical scheme, the electromagnetic shielding film with better shielding efficiency can be manufactured at lower cost, and the electromagnetic shielding film can be suitable for the requirement of industrial mass production.
In conclusion, the invention has the following beneficial effects:
firstly, the invention has better electromagnetic shielding efficiency which can reach 70-75 dB;
secondly, the metal shielding layer has more outstanding bending resistance and excellent flexibility;
thirdly, the process of the invention is simple and easy to implement, the cost is relatively lower, and the invention has mass production.
Drawings
FIG. 1 is a schematic structural view of the present embodiment;
fig. 2 is a schematic structural view of the electromagnetic shielding film for detecting the ground resistance.
In the figure: 1. a carrier film; 2. a mesh insulating layer; 3. a metal shielding layer; 4. a conductive adhesive layer; 5. a protective film; 6. a test well; 7. a CVL cover film; 8. a flexible copper clad laminate.
Detailed Description
The invention is described in detail below with reference to the figures and examples.
As shown in fig. 1, the product structures of the electromagnetic shielding film with high shielding performance provided by the present invention respectively include the following: carrier film 1, latticed insulating layer 2, latticed metal shielding layer 3, conductive adhesive layer 4, protection film 5.
The carrier film 1 of this embodiment is a non-silicon release film, and the film material thereof may be one of a polyester film, a polyimide film, and the like. The carrier film is a non-silicon release film made of polyester film and polyimide film, and the main function of the non-silicon release film is to facilitate the formation of the insulating layer 2. In addition to this, the carrier film can also serve as a support and also as a protection for the transport or processing of the insulating layer 2. Preferably, the thickness of the carrier film may be 30 to 80 μm, and most preferably 47 to 53 μm.
The insulating layer 2 is in a grid shape and is coated on either side of the carrier film 1. Preferably, the resin for forming the insulating layer may be one of an acrylic resin, a urethane resin, and an epoxy resin, and the acrylic resin, the urethane resin, and the epoxy resin may be modified by adding a curing agent, an antifreeze, a leveling agent, and the like according to actual use. The main function of the insulating layer 2 is to prevent charge overflow, and to reduce occurrence of creepage, short circuit, and the like. Considering its subsequent processing, the side of the outer surface of the insulating layer 2 facing away from the grid provides printability facilitating the printing of various ink characters. The thickness of the insulating layer is preferably 3 to 15 μm, and more preferably 6 to 8 μm.
The metal shielding layer 3 is electroplated on one side of the insulating layer 2 in a grid shape to form a grid-shaped metal layer structure. The latticed metal layer structure can avoid the adverse effect of brittle fracture of the metal shielding layer 3 during bending. The electromagnetic shielding film has more outstanding bending resistance and shows excellent flexibility. The conductive metal material of the metal shielding layer may be at least one of nickel, chromium, copper, silver, gold, nichrome, nickel-silver alloy, copper-nickel alloy, copper-silver alloy, and the like. Preferably, the metal shielding layer is of a double-layer structure formed by combining two different conductive metal materials, and the shielding performance, the corrosion resistance and the oxidation resistance of the metal shielding layer are more outstanding. The electroplating mode can be formed by chemical plating, vacuum magnetron sputtering plating, vacuum evaporation plating, electromagnetic plating or a composite process thereof. The thickness of the metal shielding layer is preferably 0.1 μm to 5 μm, and most preferably 0.3 μm.
The conductive adhesive layer 4 is an omnibearing conductive adhesive, and is coated on one side of the metal shielding layer 3 departing from the insulating layer 2, so that good filling property, conductivity and bonding strength are provided. The material can be one of epoxy resin, acrylic resin and polyurethane resin, and the epoxy resin, acrylic resin and polyurethane resin can be modified epoxy resin, modified acrylic resin or modified polyurethane resin added with a curing agent, a leveling agent and a dispersing agent. The thickness of the conductive adhesive layer is preferably between 3 μm and 20 μm, and most preferably, the thickness can be 3 μm. The high shielding effectiveness provided by the electromagnetic shielding film is mainly realized by a continuous and complete shielding structure formed by the latticed metal shielding layer 3 and the omnibearing conductive adhesive layer 4.
The protective film 5 is a release film of an organic silicon system. The protective film 5 has a protective effect on the conductive adhesive layer 4 and can provide protection for subsequent processing of products. In addition, the protective film 5 can prevent foreign matters, impurities and the like from polluting the conductive adhesive layer 4.
Referring to FIG. 1, the present invention provides a method for producing an electro-magnetic shielding film with high shielding performance
The process is described in further detail. The specific production process comprises the following steps:
step a, coating insulating resin on either side of the carrier film 1, drying the solvent to cure, and coating to form a grid-shaped insulating layer 2.
And b, electroplating conductive metal on the side of the surface of the latticed insulating layer 2, which is far away from the carrier film, to form a metal shielding layer 3. The conductive metal material may be at least one of nickel, chromium, copper, silver, gold, nickel-chromium alloy, nickel-silver alloy, copper-nickel alloy, copper-silver alloy, and the like. Preferably, the metal shielding layer is made of two metal alloys made of different materials, and the metal shielding layer with a double-layer structure made of different materials has more outstanding shielding performance, corrosion resistance and oxidation resistance, more stable performance and firmer structure. The electroplating mode can be formed by chemical plating, vacuum magnetron sputtering plating, vacuum evaporation plating, electromagnetic plating or a composite process thereof.
And c, coating conductive adhesive on one side of the surface of the metal shielding layer 3, which is far away from the insulating layer, drying and curing to form an all-dimensional conductive adhesive layer 4. Of course, the conductive adhesive layer 4 may be an anisotropic conductive adhesive layer. Preferably, the conductive adhesive layer 4 in the present invention is an all-directional conductive adhesive, which can further reflect electromagnetic waves or attenuate electromagnetic waves. The conductive adhesive is filled with conductive particles, and the conductive particles can be nickel, copper, silver, gold or at least one of nickel-clad copper, silver-clad graphite and the like.
Preferably, the conductive particle diameter of the conductive adhesive layer 4 is selected to be between 1 μm and 20 μm.
Preferably, the filling ratio of the conductive particles in the conductive adhesive layer 4 to the conductive adhesive may be 10% to 40%.
And d, forming a protective film 5 on one side of the surface of the conductive adhesive layer 4, which is far away from the latticed metal layer 3, in a laminating manner. Wherein, the protective film 5 is a release film of an organic silicon system. The film material of the protective film 5 may be one of a polyester film, a polyimide film, and the like. The protective film 5 has a protective effect on the conductive adhesive layer 4 and can be used for subsequent processing protection of products. In addition, foreign matters, impurities and the like can be prevented from polluting the conductive adhesive layer 4.
Compared with the prior art, the electromagnetic shielding film with high shielding performance provided by the invention has the advantages that the insulating layer 2 is designed to be in a grid shape, and the metal layer 3 is electroplated in the grid gaps of the insulating layer 2 to form the grid-shaped metal shielding layer 3. In turn, an all-round conductive adhesive layer 4 is coated on the side of the metal shielding layer 3 departing from the insulating layer 2. The latticed metal shielding layer 3 and the omnibearing conductive adhesive layer 4 conduct and ground the circuit of the circuit board. In addition, the latticed metal shielding layer 3 and the omnibearing conductive adhesive layer 4 form a continuous, complete and three-dimensional latticed electromagnetic wave shielding body structure together, electromagnetic waves can be reflected twice or inhibited in the latticed shielding layer, and the conductive adhesive layer 4 leads away and releases redundant charges. The unique shield structure enables the shielding effectiveness of the electromagnetic shielding film of the present invention to be as high as 75 db. Meanwhile, the metal shielding layer 3 filled on one side of the grid-shaped insulating layer 2 has different structural characteristics from the prior rigid flat-plate-shaped metal shielding layer due to the special grid-shaped process characteristics, so that the bending resistance of the metal shielding layer is more outstanding, and excellent flexibility is realized. In addition, compared with similar products, the method has the advantages of simple process, easy implementation, relatively lower cost and more mass production.
The electromagnetic shielding film described by the invention is submitted to inspection, and the obtained product characteristic detection data are as follows:
| item | The result of the detection | Detection method |
| Shielding performance (db) | 70-75db | SJ20524-1995 (10MHz~3000MHz) |
| Ground resistance (omega) | ≤1 | GND phi =1mm, after floating tin |
| Resistance to bending | Not less than 25000 times | Radius of curvature R =1.0mm |
Referring to fig. 2, the ground resistance testing method includes: and pressing the shielding film to cover the FPC test hole 6, pressing and transferring to test the grounding resistance of different grounding holes, then selecting baking at 160-170 ℃ for 1H curing, and testing the grounding resistance after reflow soldering or tin floating.
The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may occur to those skilled in the art without departing from the principle of the invention, and are considered to be within the scope of the invention.
Claims (14)
1. An electromagnetic shielding film with high shielding performance is characterized in that: the insulating layer, the metal shielding layer and the conductive adhesive layer are sequentially arranged, one side of the insulating layer is in a network shape, and one side of the metal shielding layer, which is connected with the insulating layer, is in a network shape matched with the insulating layer.
2. The electromagnetic shielding film with high shielding performance as claimed in claim 1, wherein: the electromagnetic shielding film further comprises a carrier film, and the carrier film is arranged on one side, far away from the metal shielding layer, of the grid insulating layer.
3. The high-shielding-performance electromagnetic shielding film according to claim 2, wherein: the carrier film is made of a non-silicon release film.
4. The high-shielding-performance electromagnetic shielding film according to claim 3, wherein: the carrier film is a polyester film or a polyimide film.
5. The electromagnetic shielding film with high shielding performance as claimed in claim 1, wherein: the electromagnetic shielding film further comprises a protective film, the protective film is arranged on one side, far away from the metal shielding layer, of the conductive adhesive layer, the protective film is a release film of an organic silicon system, and the protective film is a polyester film or a polyimide film.
6. The electromagnetic shielding film with high shielding performance as claimed in claim 1, wherein: the insulating layer is made of resin, and the resin for preparing the insulating layer is one of acrylic resin, polyurethane and epoxy resin.
7. The high-shielding-performance electromagnetic shielding film according to claim 8, wherein: the thickness of the insulating layer is between 3 and 15 μm.
8. The electromagnetic shielding film with high shielding performance as claimed in claim 1, wherein: the metal shielding layer is a composite metal layer formed by two different conductive metal materials.
9. The high-shielding-performance electromagnetic shielding film according to claim 8, wherein: the conductive metal material may be one of nickel, chromium, copper, silver and gold.
10. A high-shielding electromagnetic shielding film according to claims 8 to 9, wherein: the thickness of the metal shielding layer is 0.1-5 μm.
11. The electromagnetic shielding film with high shielding performance as claimed in claim 1, wherein: the conductive adhesive layer is an all-dimensional conductive adhesive layer.
12. A high-shielding-performance electro-magnetic shielding film as claimed in claim 1, 10 or 11, wherein: the conductive adhesive layer is filled with conductive particles, the conductive particles can be nickel, copper, silver and gold or at least one of nickel-clad copper, silver-clad copper and silver-clad graphite, the particle diameter of the conductive particles is selected to be between 1 and 20 mu m, and the filling ratio of the conductive particles in the conductive adhesive is between 10 and 40 percent.
13. The high-shielding-performance electromagnetic shielding film according to claim 12, wherein: the thickness of the conductive adhesive layer is between 3 and 20 mu m.
14. A process for manufacturing an electromagnetic shielding film with high shielding performance as claimed in claims 1 to 13, wherein the process comprises the following steps:
step a, coating insulating resin on one side of a carrier film to form a grid-shaped insulating layer;
step b, electroplating conductive metal on one latticed side of the latticed insulating layer to form a latticed metal shielding layer;
c, coating conductive adhesive on one side of the surface of the grid metal shielding layer, which is far away from the insulating layer, to form a conductive adhesive layer;
and d, forming a protective film on one side of the surface of the conductive adhesive layer, which is far away from the metal shielding layer, in a laminating manner.
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| CN202010046903.9A CN111148426A (en) | 2020-01-16 | 2020-01-16 | Electromagnetic shielding film with high shielding performance and production process thereof |
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| CN202010046903.9A CN111148426A (en) | 2020-01-16 | 2020-01-16 | Electromagnetic shielding film with high shielding performance and production process thereof |
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| CN111148426A true CN111148426A (en) | 2020-05-12 |
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| CN202010046903.9A Pending CN111148426A (en) | 2020-01-16 | 2020-01-16 | Electromagnetic shielding film with high shielding performance and production process thereof |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112332190A (en) * | 2020-07-27 | 2021-02-05 | 深圳市卓汉材料技术有限公司 | Method for manufacturing composite grounding film, method for manufacturing high-temperature-resistant grounding elastic piece and structure |
| CN115746740A (en) * | 2022-11-04 | 2023-03-07 | 四川普利司德高分子新材料有限公司 | Electromagnetic shielding protection film |
| CN116709759A (en) * | 2023-07-03 | 2023-09-05 | 广州方邦电子股份有限公司 | Electromagnetic shielding film and circuit board |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102510712A (en) * | 2011-11-14 | 2012-06-20 | 广州方邦电子有限公司 | Paper-thin screened film with extremely high screening efficiency and manufacturing method therefor |
| CN106937522A (en) * | 2017-04-05 | 2017-07-07 | 合肥美凯电子有限公司 | A kind of novel electromagnetic shielding film |
| CN109168313A (en) * | 2018-09-10 | 2019-01-08 | 深圳科诺桥科技股份有限公司 | Electromagnetic shielding film and wiring board comprising screened film |
| CN211352978U (en) * | 2020-01-16 | 2020-08-25 | 广东桑泰科技有限公司 | Electromagnetic shielding film with high shielding efficiency |
-
2020
- 2020-01-16 CN CN202010046903.9A patent/CN111148426A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102510712A (en) * | 2011-11-14 | 2012-06-20 | 广州方邦电子有限公司 | Paper-thin screened film with extremely high screening efficiency and manufacturing method therefor |
| CN106937522A (en) * | 2017-04-05 | 2017-07-07 | 合肥美凯电子有限公司 | A kind of novel electromagnetic shielding film |
| CN109168313A (en) * | 2018-09-10 | 2019-01-08 | 深圳科诺桥科技股份有限公司 | Electromagnetic shielding film and wiring board comprising screened film |
| CN211352978U (en) * | 2020-01-16 | 2020-08-25 | 广东桑泰科技有限公司 | Electromagnetic shielding film with high shielding efficiency |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112332190A (en) * | 2020-07-27 | 2021-02-05 | 深圳市卓汉材料技术有限公司 | Method for manufacturing composite grounding film, method for manufacturing high-temperature-resistant grounding elastic piece and structure |
| CN115746740A (en) * | 2022-11-04 | 2023-03-07 | 四川普利司德高分子新材料有限公司 | Electromagnetic shielding protection film |
| CN116709759A (en) * | 2023-07-03 | 2023-09-05 | 广州方邦电子股份有限公司 | Electromagnetic shielding film and circuit board |
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